text: 
  /*
   * Copyright (C) Igor Sysoev
   * Copyright (C) Nginx, Inc.
   */
  
  
  #include <ngx_config.h>
  #include <ngx_core.h>
  #include <ngx_http.h>
  
  
  typedef struct {
      ngx_array_t                    caches;  /* ngx_http_file_cache_t * */
  } ngx_http_proxy_main_conf_t;
  
  
  typedef struct ngx_http_proxy_rewrite_s  ngx_http_proxy_rewrite_t;
  
  typedef ngx_int_t (*ngx_http_proxy_rewrite_pt)(ngx_http_request_t *r,
      ngx_table_elt_t *h, size_t prefix, size_t len,
      ngx_http_proxy_rewrite_t *pr);
  
  struct ngx_http_proxy_rewrite_s {
      ngx_http_proxy_rewrite_pt      handler;
  
      union {
          ngx_http_complex_value_t   complex;
  #if (NGX_PCRE)
          ngx_http_regex_t          *regex;
  #endif
      } pattern;
  
      ngx_http_complex_value_t       replacement;
  };
  
  
  typedef struct {
      ngx_str_t                      key_start;
      ngx_str_t                      schema;
      ngx_str_t                      host_header;
      ngx_str_t                      port;
      ngx_str_t                      uri;
  } ngx_http_proxy_vars_t;
  
  
  typedef struct {
      ngx_array_t                   *flushes;
      ngx_array_t                   *lengths;
      ngx_array_t                   *values;
      ngx_hash_t                     hash;
  } ngx_http_proxy_headers_t;
  
  
  typedef struct {
      ngx_http_upstream_conf_t       upstream;
  
      ngx_array_t                   *body_flushes;
      ngx_array_t                   *body_lengths;
      ngx_array_t                   *body_values;
      ngx_str_t                      body_source;
  
      ngx_http_proxy_headers_t       headers;
  #if (NGX_HTTP_CACHE)
      ngx_http_proxy_headers_t       headers_cache;
  #endif
      ngx_array_t                   *headers_source;
  
      ngx_array_t                   *proxy_lengths;
      ngx_array_t                   *proxy_values;
  
      ngx_array_t                   *redirects;
      ngx_array_t                   *cookie_domains;
      ngx_array_t                   *cookie_paths;
  
      ngx_http_complex_value_t      *method;
      ngx_str_t                      location;
      ngx_str_t                      url;
  
  #if (NGX_HTTP_CACHE)
      ngx_http_complex_value_t       cache_key;
  #endif
  
      ngx_http_proxy_vars_t          vars;
  
      ngx_flag_t                     redirect;
  
      ngx_uint_t                     http_version;
  
      ngx_uint_t                     headers_hash_max_size;
      ngx_uint_t                     headers_hash_bucket_size;
  
  #if (NGX_HTTP_SSL)
      ngx_uint_t                     ssl;
      ngx_uint_t                     ssl_protocols;
      ngx_str_t                      ssl_ciphers;
      ngx_uint_t                     ssl_verify_depth;
      ngx_str_t                      ssl_trusted_certificate;
      ngx_str_t                      ssl_crl;
      ngx_str_t                      ssl_certificate;
      ngx_str_t                      ssl_certificate_key;
      ngx_array_t                   *ssl_passwords;
  #endif
  } ngx_http_proxy_loc_conf_t;
  
  
  typedef struct {
      ngx_http_status_t              status;
      ngx_http_chunked_t             chunked;
      ngx_http_proxy_vars_t          vars;
      off_t                          internal_body_length;
  
      ngx_chain_t                   *free;
      ngx_chain_t                   *busy;
  
      unsigned                       head:1;
      unsigned                       internal_chunked:1;
      unsigned                       header_sent:1;
  } ngx_http_proxy_ctx_t;
  
  
  static ngx_int_t ngx_http_proxy_eval(ngx_http_request_t *r,
      ngx_http_proxy_ctx_t *ctx, ngx_http_proxy_loc_conf_t *plcf);
  #if (NGX_HTTP_CACHE)
  static ngx_int_t ngx_http_proxy_create_key(ngx_http_request_t *r);
  #endif
  static ngx_int_t ngx_http_proxy_create_request(ngx_http_request_t *r);
  static ngx_int_t ngx_http_proxy_reinit_request(ngx_http_request_t *r);
  static ngx_int_t ngx_http_proxy_body_output_filter(void *data, ngx_chain_t *in);
  static ngx_int_t ngx_http_proxy_process_status_line(ngx_http_request_t *r);
  static ngx_int_t ngx_http_proxy_process_header(ngx_http_request_t *r);
  static ngx_int_t ngx_http_proxy_input_filter_init(void *data);
  static ngx_int_t ngx_http_proxy_copy_filter(ngx_event_pipe_t *p,
      ngx_buf_t *buf);
  static ngx_int_t ngx_http_proxy_chunked_filter(ngx_event_pipe_t *p,
      ngx_buf_t *buf);
  static ngx_int_t ngx_http_proxy_non_buffered_copy_filter(void *data,
      ssize_t bytes);
  static ngx_int_t ngx_http_proxy_non_buffered_chunked_filter(void *data,
      ssize_t bytes);
  static void ngx_http_proxy_abort_request(ngx_http_request_t *r);
  static void ngx_http_proxy_finalize_request(ngx_http_request_t *r,
      ngx_int_t rc);
  
  static ngx_int_t ngx_http_proxy_host_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data);
  static ngx_int_t ngx_http_proxy_port_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data);
  static ngx_int_t
      ngx_http_proxy_add_x_forwarded_for_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data);
  static ngx_int_t
      ngx_http_proxy_internal_body_length_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data);
  static ngx_int_t ngx_http_proxy_internal_chunked_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data);
  static ngx_int_t ngx_http_proxy_rewrite_redirect(ngx_http_request_t *r,
      ngx_table_elt_t *h, size_t prefix);
  static ngx_int_t ngx_http_proxy_rewrite_cookie(ngx_http_request_t *r,
      ngx_table_elt_t *h);
  static ngx_int_t ngx_http_proxy_rewrite_cookie_value(ngx_http_request_t *r,
      ngx_table_elt_t *h, u_char *value, ngx_array_t *rewrites);
  static ngx_int_t ngx_http_proxy_rewrite(ngx_http_request_t *r,
      ngx_table_elt_t *h, size_t prefix, size_t len, ngx_str_t *replacement);
  
  static ngx_int_t ngx_http_proxy_add_variables(ngx_conf_t *cf);
  static void *ngx_http_proxy_create_main_conf(ngx_conf_t *cf);
  static void *ngx_http_proxy_create_loc_conf(ngx_conf_t *cf);
  static char *ngx_http_proxy_merge_loc_conf(ngx_conf_t *cf,
      void *parent, void *child);
  static ngx_int_t ngx_http_proxy_init_headers(ngx_conf_t *cf,
      ngx_http_proxy_loc_conf_t *conf, ngx_http_proxy_headers_t *headers,
      ngx_keyval_t *default_headers);
  
  static char *ngx_http_proxy_pass(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  static char *ngx_http_proxy_redirect(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  static char *ngx_http_proxy_cookie_domain(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  static char *ngx_http_proxy_cookie_path(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  static char *ngx_http_proxy_store(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  #if (NGX_HTTP_CACHE)
  static char *ngx_http_proxy_cache(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  static char *ngx_http_proxy_cache_key(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  #endif
  #if (NGX_HTTP_SSL)
  static char *ngx_http_proxy_ssl_password_file(ngx_conf_t *cf,
      ngx_command_t *cmd, void *conf);
  #endif
  
  static char *ngx_http_proxy_lowat_check(ngx_conf_t *cf, void *post, void *data);
  
  static ngx_int_t ngx_http_proxy_rewrite_regex(ngx_conf_t *cf,
      ngx_http_proxy_rewrite_t *pr, ngx_str_t *regex, ngx_uint_t caseless);
  
  #if (NGX_HTTP_SSL)
  static ngx_int_t ngx_http_proxy_set_ssl(ngx_conf_t *cf,
      ngx_http_proxy_loc_conf_t *plcf);
  #endif
  static void ngx_http_proxy_set_vars(ngx_url_t *u, ngx_http_proxy_vars_t *v);
  
  
  static ngx_conf_post_t  ngx_http_proxy_lowat_post =
      { ngx_http_proxy_lowat_check };
  
  
  static ngx_conf_bitmask_t  ngx_http_proxy_next_upstream_masks[] = {
      { ngx_string("error"), NGX_HTTP_UPSTREAM_FT_ERROR },
      { ngx_string("timeout"), NGX_HTTP_UPSTREAM_FT_TIMEOUT },
      { ngx_string("invalid_header"), NGX_HTTP_UPSTREAM_FT_INVALID_HEADER },
      { ngx_string("non_idempotent"), NGX_HTTP_UPSTREAM_FT_NON_IDEMPOTENT },
      { ngx_string("http_500"), NGX_HTTP_UPSTREAM_FT_HTTP_500 },
      { ngx_string("http_502"), NGX_HTTP_UPSTREAM_FT_HTTP_502 },
      { ngx_string("http_503"), NGX_HTTP_UPSTREAM_FT_HTTP_503 },
      { ngx_string("http_504"), NGX_HTTP_UPSTREAM_FT_HTTP_504 },
      { ngx_string("http_403"), NGX_HTTP_UPSTREAM_FT_HTTP_403 },
      { ngx_string("http_404"), NGX_HTTP_UPSTREAM_FT_HTTP_404 },
      { ngx_string("http_429"), NGX_HTTP_UPSTREAM_FT_HTTP_429 },
      { ngx_string("updating"), NGX_HTTP_UPSTREAM_FT_UPDATING },
      { ngx_string("off"), NGX_HTTP_UPSTREAM_FT_OFF },
      { ngx_null_string, 0 }
  };
  
  
  #if (NGX_HTTP_SSL)
  
  static ngx_conf_bitmask_t  ngx_http_proxy_ssl_protocols[] = {
      { ngx_string("SSLv2"), NGX_SSL_SSLv2 },
      { ngx_string("SSLv3"), NGX_SSL_SSLv3 },
      { ngx_string("TLSv1"), NGX_SSL_TLSv1 },
      { ngx_string("TLSv1.1"), NGX_SSL_TLSv1_1 },
      { ngx_string("TLSv1.2"), NGX_SSL_TLSv1_2 },
      { ngx_string("TLSv1.3"), NGX_SSL_TLSv1_3 },
      { ngx_null_string, 0 }
  };
  
  #endif
  
  
  static ngx_conf_enum_t  ngx_http_proxy_http_version[] = {
      { ngx_string("1.0"), NGX_HTTP_VERSION_10 },
      { ngx_string("1.1"), NGX_HTTP_VERSION_11 },
      { ngx_null_string, 0 }
  };
  
  
  ngx_module_t  ngx_http_proxy_module;
  
  
  static ngx_command_t  ngx_http_proxy_commands[] = {
  
      { ngx_string("proxy_pass"),
        NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF|NGX_HTTP_LMT_CONF|NGX_CONF_TAKE1,
        ngx_http_proxy_pass,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("proxy_redirect"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE12,
        ngx_http_proxy_redirect,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("proxy_cookie_domain"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE12,
        ngx_http_proxy_cookie_domain,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("proxy_cookie_path"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE12,
        ngx_http_proxy_cookie_path,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("proxy_store"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_http_proxy_store,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("proxy_store_access"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE123,
        ngx_conf_set_access_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.store_access),
        NULL },
  
      { ngx_string("proxy_buffering"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.buffering),
        NULL },
  
      { ngx_string("proxy_request_buffering"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.request_buffering),
        NULL },
  
      { ngx_string("proxy_ignore_client_abort"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.ignore_client_abort),
        NULL },
  
      { ngx_string("proxy_bind"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE12,
        ngx_http_upstream_bind_set_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.local),
        NULL },
  
      { ngx_string("proxy_connect_timeout"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_msec_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.connect_timeout),
        NULL },
  
      { ngx_string("proxy_send_timeout"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_msec_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.send_timeout),
        NULL },
  
      { ngx_string("proxy_send_lowat"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.send_lowat),
        &ngx_http_proxy_lowat_post },
  
      { ngx_string("proxy_intercept_errors"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.intercept_errors),
        NULL },
  
      { ngx_string("proxy_set_header"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE2,
        ngx_conf_set_keyval_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, headers_source),
        NULL },
  
      { ngx_string("proxy_headers_hash_max_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_num_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, headers_hash_max_size),
        NULL },
  
      { ngx_string("proxy_headers_hash_bucket_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_num_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, headers_hash_bucket_size),
        NULL },
  
      { ngx_string("proxy_set_body"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_str_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, body_source),
        NULL },
  
      { ngx_string("proxy_method"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_http_set_complex_value_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, method),
        NULL },
  
      { ngx_string("proxy_pass_request_headers"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.pass_request_headers),
        NULL },
  
      { ngx_string("proxy_pass_request_body"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.pass_request_body),
        NULL },
  
      { ngx_string("proxy_buffer_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.buffer_size),
        NULL },
  
      { ngx_string("proxy_read_timeout"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_msec_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.read_timeout),
        NULL },
  
      { ngx_string("proxy_buffers"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE2,
        ngx_conf_set_bufs_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.bufs),
        NULL },
  
      { ngx_string("proxy_busy_buffers_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.busy_buffers_size_conf),
        NULL },
  
      { ngx_string("proxy_force_ranges"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.force_ranges),
        NULL },
  
      { ngx_string("proxy_limit_rate"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.limit_rate),
        NULL },
  
  #if (NGX_HTTP_CACHE)
  
      { ngx_string("proxy_cache"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_http_proxy_cache,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("proxy_cache_key"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_http_proxy_cache_key,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("proxy_cache_path"),
        NGX_HTTP_MAIN_CONF|NGX_CONF_2MORE,
        ngx_http_file_cache_set_slot,
        NGX_HTTP_MAIN_CONF_OFFSET,
        offsetof(ngx_http_proxy_main_conf_t, caches),
        &ngx_http_proxy_module },
  
      { ngx_string("proxy_cache_bypass"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
        ngx_http_set_predicate_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_bypass),
        NULL },
  
      { ngx_string("proxy_no_cache"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
        ngx_http_set_predicate_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.no_cache),
        NULL },
  
      { ngx_string("proxy_cache_valid"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
        ngx_http_file_cache_valid_set_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_valid),
        NULL },
  
      { ngx_string("proxy_cache_min_uses"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_num_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_min_uses),
        NULL },
  
      { ngx_string("proxy_cache_max_range_offset"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_off_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_max_range_offset),
        NULL },
  
      { ngx_string("proxy_cache_use_stale"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
        ngx_conf_set_bitmask_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_use_stale),
        &ngx_http_proxy_next_upstream_masks },
  
      { ngx_string("proxy_cache_methods"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
        ngx_conf_set_bitmask_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_methods),
        &ngx_http_upstream_cache_method_mask },
  
      { ngx_string("proxy_cache_lock"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_lock),
        NULL },
  
      { ngx_string("proxy_cache_lock_timeout"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_msec_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_lock_timeout),
        NULL },
  
      { ngx_string("proxy_cache_lock_age"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_msec_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_lock_age),
        NULL },
  
      { ngx_string("proxy_cache_revalidate"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_revalidate),
        NULL },
  
      { ngx_string("proxy_cache_convert_head"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_convert_head),
        NULL },
  
      { ngx_string("proxy_cache_background_update"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.cache_background_update),
        NULL },
  
  #endif
  
      { ngx_string("proxy_temp_path"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1234,
        ngx_conf_set_path_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.temp_path),
        NULL },
  
      { ngx_string("proxy_max_temp_file_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.max_temp_file_size_conf),
        NULL },
  
      { ngx_string("proxy_temp_file_write_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.temp_file_write_size_conf),
        NULL },
  
      { ngx_string("proxy_next_upstream"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
        ngx_conf_set_bitmask_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.next_upstream),
        &ngx_http_proxy_next_upstream_masks },
  
      { ngx_string("proxy_next_upstream_tries"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_num_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.next_upstream_tries),
        NULL },
  
      { ngx_string("proxy_next_upstream_timeout"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_msec_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.next_upstream_timeout),
        NULL },
  
      { ngx_string("proxy_pass_header"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_str_array_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.pass_headers),
        NULL },
  
      { ngx_string("proxy_hide_header"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_str_array_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.hide_headers),
        NULL },
  
      { ngx_string("proxy_ignore_headers"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
        ngx_conf_set_bitmask_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.ignore_headers),
        &ngx_http_upstream_ignore_headers_masks },
  
      { ngx_string("proxy_http_version"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_enum_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, http_version),
        &ngx_http_proxy_http_version },
  
  #if (NGX_HTTP_SSL)
  
      { ngx_string("proxy_ssl_session_reuse"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.ssl_session_reuse),
        NULL },
  
      { ngx_string("proxy_ssl_protocols"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE,
        ngx_conf_set_bitmask_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, ssl_protocols),
        &ngx_http_proxy_ssl_protocols },
  
      { ngx_string("proxy_ssl_ciphers"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_str_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, ssl_ciphers),
        NULL },
  
      { ngx_string("proxy_ssl_name"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_http_set_complex_value_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.ssl_name),
        NULL },
  
      { ngx_string("proxy_ssl_server_name"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.ssl_server_name),
        NULL },
  
      { ngx_string("proxy_ssl_verify"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, upstream.ssl_verify),
        NULL },
  
      { ngx_string("proxy_ssl_verify_depth"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_num_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, ssl_verify_depth),
        NULL },
  
      { ngx_string("proxy_ssl_trusted_certificate"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_str_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, ssl_trusted_certificate),
        NULL },
  
      { ngx_string("proxy_ssl_crl"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_str_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, ssl_crl),
        NULL },
  
      { ngx_string("proxy_ssl_certificate"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_str_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, ssl_certificate),
        NULL },
  
      { ngx_string("proxy_ssl_certificate_key"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_str_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_proxy_loc_conf_t, ssl_certificate_key),
        NULL },
  
      { ngx_string("proxy_ssl_password_file"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_http_proxy_ssl_password_file,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
  #endif
  
        ngx_null_command
  };
  
  
  static ngx_http_module_t  ngx_http_proxy_module_ctx = {
      ngx_http_proxy_add_variables,          /* preconfiguration */
      NULL,                                  /* postconfiguration */
  
      ngx_http_proxy_create_main_conf,       /* create main configuration */
      NULL,                                  /* init main configuration */
  
      NULL,                                  /* create server configuration */
      NULL,                                  /* merge server configuration */
  
      ngx_http_proxy_create_loc_conf,        /* create location configuration */
      ngx_http_proxy_merge_loc_conf          /* merge location configuration */
  };
  
  
  ngx_module_t  ngx_http_proxy_module = {
      NGX_MODULE_V1,
      &ngx_http_proxy_module_ctx,            /* module context */
      ngx_http_proxy_commands,               /* module directives */
      NGX_HTTP_MODULE,                       /* module type */
      NULL,                                  /* init master */
      NULL,                                  /* init module */
      NULL,                                  /* init process */
      NULL,                                  /* init thread */
      NULL,                                  /* exit thread */
      NULL,                                  /* exit process */
      NULL,                                  /* exit master */
      NGX_MODULE_V1_PADDING
  };
  
  
  static char  ngx_http_proxy_version[] = " HTTP/1.0" CRLF;
  static char  ngx_http_proxy_version_11[] = " HTTP/1.1" CRLF;
  
  
  static ngx_keyval_t  ngx_http_proxy_headers[] = {
      { ngx_string("Host"), ngx_string("$proxy_host") },
      { ngx_string("Connection"), ngx_string("close") },
      { ngx_string("Content-Length"), ngx_string("$proxy_internal_body_length") },
      { ngx_string("Transfer-Encoding"), ngx_string("$proxy_internal_chunked") },
      { ngx_string("TE"), ngx_string("") },
      { ngx_string("Keep-Alive"), ngx_string("") },
      { ngx_string("Expect"), ngx_string("") },
      { ngx_string("Upgrade"), ngx_string("") },
      { ngx_null_string, ngx_null_string }
  };
  
  
  static ngx_str_t  ngx_http_proxy_hide_headers[] = {
      ngx_string("Date"),
      ngx_string("Server"),
      ngx_string("X-Pad"),
      ngx_string("X-Accel-Expires"),
      ngx_string("X-Accel-Redirect"),
      ngx_string("X-Accel-Limit-Rate"),
      ngx_string("X-Accel-Buffering"),
      ngx_string("X-Accel-Charset"),
      ngx_null_string
  };
  
  
  #if (NGX_HTTP_CACHE)
  
  static ngx_keyval_t  ngx_http_proxy_cache_headers[] = {
      { ngx_string("Host"), ngx_string("$proxy_host") },
      { ngx_string("Connection"), ngx_string("close") },
      { ngx_string("Content-Length"), ngx_string("$proxy_internal_body_length") },
      { ngx_string("Transfer-Encoding"), ngx_string("$proxy_internal_chunked") },
      { ngx_string("TE"), ngx_string("") },
      { ngx_string("Keep-Alive"), ngx_string("") },
      { ngx_string("Expect"), ngx_string("") },
      { ngx_string("Upgrade"), ngx_string("") },
      { ngx_string("If-Modified-Since"),
        ngx_string("$upstream_cache_last_modified") },
      { ngx_string("If-Unmodified-Since"), ngx_string("") },
      { ngx_string("If-None-Match"), ngx_string("$upstream_cache_etag") },
      { ngx_string("If-Match"), ngx_string("") },
      { ngx_string("Range"), ngx_string("") },
      { ngx_string("If-Range"), ngx_string("") },
      { ngx_null_string, ngx_null_string }
  };
  
  #endif
  
  
  static ngx_http_variable_t  ngx_http_proxy_vars[] = {
  
      { ngx_string("proxy_host"), NULL, ngx_http_proxy_host_variable, 0,
        NGX_HTTP_VAR_CHANGEABLE|NGX_HTTP_VAR_NOCACHEABLE, 0 },
  
      { ngx_string("proxy_port"), NULL, ngx_http_proxy_port_variable, 0,
        NGX_HTTP_VAR_CHANGEABLE|NGX_HTTP_VAR_NOCACHEABLE, 0 },
  
      { ngx_string("proxy_add_x_forwarded_for"), NULL,
        ngx_http_proxy_add_x_forwarded_for_variable, 0, 0, 0 },
  
  #if 0
      { ngx_string("proxy_add_via"), NULL, NULL, 0, NGX_HTTP_VAR_NOHASH, 0 },
  #endif
  
      { ngx_string("proxy_internal_body_length"), NULL,
        ngx_http_proxy_internal_body_length_variable, 0,
        NGX_HTTP_VAR_NOCACHEABLE|NGX_HTTP_VAR_NOHASH, 0 },
  
      { ngx_string("proxy_internal_chunked"), NULL,
        ngx_http_proxy_internal_chunked_variable, 0,
        NGX_HTTP_VAR_NOCACHEABLE|NGX_HTTP_VAR_NOHASH, 0 },
  
        ngx_http_null_variable
  };
  
  
  static ngx_path_init_t  ngx_http_proxy_temp_path = {
      ngx_string(NGX_HTTP_PROXY_TEMP_PATH), { 1, 2, 0 }
  };
  
  
  static ngx_int_t
  ngx_http_proxy_handler(ngx_http_request_t *r)
  {
      ngx_int_t                    rc;
      ngx_http_upstream_t         *u;
      ngx_http_proxy_ctx_t        *ctx;
      ngx_http_proxy_loc_conf_t   *plcf;
  #if (NGX_HTTP_CACHE)
      ngx_http_proxy_main_conf_t  *pmcf;
  #endif
  
      if (ngx_http_upstream_create(r) != NGX_OK) {
          return NGX_HTTP_INTERNAL_SERVER_ERROR;
      }
  
      ctx = ngx_pcalloc(r->pool, sizeof(ngx_http_proxy_ctx_t));
      if (ctx == NULL) {
          return NGX_HTTP_INTERNAL_SERVER_ERROR;
      }
  
      ngx_http_set_ctx(r, ctx, ngx_http_proxy_module);
  
      plcf = ngx_http_get_module_loc_conf(r, ngx_http_proxy_module);
  
      u = r->upstream;
  
      if (plcf->proxy_lengths == NULL) {
          ctx->vars = plcf->vars;
          u->schema = plcf->vars.schema;
  #if (NGX_HTTP_SSL)
          u->ssl = (plcf->upstream.ssl != NULL);
  #endif
  
      } else {
          if (ngx_http_proxy_eval(r, ctx, plcf) != NGX_OK) {
              return NGX_HTTP_INTERNAL_SERVER_ERROR;
          }
      }
  
      u->output.tag = (ngx_buf_tag_t) &ngx_http_proxy_module;
  
      u->conf = &plcf->upstream;
  
  #if (NGX_HTTP_CACHE)
      pmcf = ngx_http_get_module_main_conf(r, ngx_http_proxy_module);
  
      u->caches = &pmcf->caches;
      u->create_key = ngx_http_proxy_create_key;
  #endif
  
      u->create_request = ngx_http_proxy_create_request;
      u->reinit_request = ngx_http_proxy_reinit_request;
      u->process_header = ngx_http_proxy_process_status_line;
      u->abort_request = ngx_http_proxy_abort_request;
      u->finalize_request = ngx_http_proxy_finalize_request;
      r->state = 0;
  
      if (plcf->redirects) {
          u->rewrite_redirect = ngx_http_proxy_rewrite_redirect;
      }
  
      if (plcf->cookie_domains || plcf->cookie_paths) {
          u->rewrite_cookie = ngx_http_proxy_rewrite_cookie;
      }
  
      u->buffering = plcf->upstream.buffering;
  
      u->pipe = ngx_pcalloc(r->pool, sizeof(ngx_event_pipe_t));
      if (u->pipe == NULL) {
          return NGX_HTTP_INTERNAL_SERVER_ERROR;
      }
  
      u->pipe->input_filter = ngx_http_proxy_copy_filter;
      u->pipe->input_ctx = r;
  
      u->input_filter_init = ngx_http_proxy_input_filter_init;
      u->input_filter = ngx_http_proxy_non_buffered_copy_filter;
      u->input_filter_ctx = r;
  
      u->accel = 1;
  
      if (!plcf->upstream.request_buffering
          && plcf->body_values == NULL && plcf->upstream.pass_request_body
          && (!r->headers_in.chunked
              || plcf->http_version == NGX_HTTP_VERSION_11))
      {
          r->request_body_no_buffering = 1;
      }
  
      rc = ngx_http_read_client_request_body(r, ngx_http_upstream_init);
  
      if (rc >= NGX_HTTP_SPECIAL_RESPONSE) {
          return rc;
      }
  
      return NGX_DONE;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_eval(ngx_http_request_t *r, ngx_http_proxy_ctx_t *ctx,
      ngx_http_proxy_loc_conf_t *plcf)
  {
      u_char               *p;
      size_t                add;
      u_short               port;
      ngx_str_t             proxy;
      ngx_url_t             url;
      ngx_http_upstream_t  *u;
  
      if (ngx_http_script_run(r, &proxy, plcf->proxy_lengths->elts, 0,
                              plcf->proxy_values->elts)
          == NULL)
      {
          return NGX_ERROR;
      }
  
      if (proxy.len > 7
          && ngx_strncasecmp(proxy.data, (u_char *) "http://", 7) == 0)
      {
          add = 7;
          port = 80;
  
  #if (NGX_HTTP_SSL)
  
      } else if (proxy.len > 8
                 && ngx_strncasecmp(proxy.data, (u_char *) "https://", 8) == 0)
      {
          add = 8;
          port = 443;
          r->upstream->ssl = 1;
  
  #endif
  
      } else {
          ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                        "invalid URL prefix in \"%V\"", &proxy);
          return NGX_ERROR;
      }
  
      u = r->upstream;
  
      u->schema.len = add;
      u->schema.data = proxy.data;
  
      ngx_memzero(&url, sizeof(ngx_url_t));
  
      url.url.len = proxy.len - add;
      url.url.data = proxy.data + add;
      url.default_port = port;
      url.uri_part = 1;
      url.no_resolve = 1;
  
      if (ngx_parse_url(r->pool, &url) != NGX_OK) {
          if (url.err) {
              ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                            "%s in upstream \"%V\"", url.err, &url.url);
          }
  
          return NGX_ERROR;
      }
  
      if (url.uri.len) {
          if (url.uri.data[0] == '?') {
              p = ngx_pnalloc(r->pool, url.uri.len + 1);
              if (p == NULL) {
                  return NGX_ERROR;
              }
  
              *p++ = '/';
              ngx_memcpy(p, url.uri.data, url.uri.len);
  
              url.uri.len++;
              url.uri.data = p - 1;
          }
      }
  
      ctx->vars.key_start = u->schema;
  
      ngx_http_proxy_set_vars(&url, &ctx->vars);
  
      u->resolved = ngx_pcalloc(r->pool, sizeof(ngx_http_upstream_resolved_t));
      if (u->resolved == NULL) {
          return NGX_ERROR;
      }
  
      if (url.addrs) {
          u->resolved->sockaddr = url.addrs[0].sockaddr;
          u->resolved->socklen = url.addrs[0].socklen;
          u->resolved->name = url.addrs[0].name;
          u->resolved->naddrs = 1;
      }
  
      u->resolved->host = url.host;
      u->resolved->port = (in_port_t) (url.no_port ? port : url.port);
      u->resolved->no_port = url.no_port;
  
      return NGX_OK;
  }
  
  
  #if (NGX_HTTP_CACHE)
  
  static ngx_int_t
  ngx_http_proxy_create_key(ngx_http_request_t *r)
  {
      size_t                      len, loc_len;
      u_char                     *p;
      uintptr_t                   escape;
      ngx_str_t                  *key;
      ngx_http_upstream_t        *u;
      ngx_http_proxy_ctx_t       *ctx;
      ngx_http_proxy_loc_conf_t  *plcf;
  
      u = r->upstream;
  
      plcf = ngx_http_get_module_loc_conf(r, ngx_http_proxy_module);
  
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      key = ngx_array_push(&r->cache->keys);
      if (key == NULL) {
          return NGX_ERROR;
      }
  
      if (plcf->cache_key.value.data) {
  
          if (ngx_http_complex_value(r, &plcf->cache_key, key) != NGX_OK) {
              return NGX_ERROR;
          }
  
          return NGX_OK;
      }
  
      *key = ctx->vars.key_start;
  
      key = ngx_array_push(&r->cache->keys);
      if (key == NULL) {
          return NGX_ERROR;
      }
  
      if (plcf->proxy_lengths && ctx->vars.uri.len) {
  
          *key = ctx->vars.uri;
          u->uri = ctx->vars.uri;
  
          return NGX_OK;
  
      } else if (ctx->vars.uri.len == 0 && r->valid_unparsed_uri && r == r->main)
      {
          *key = r->unparsed_uri;
          u->uri = r->unparsed_uri;
  
          return NGX_OK;
      }
  
      loc_len = (r->valid_location && ctx->vars.uri.len) ? plcf->location.len : 0;
  
      if (r->quoted_uri || r->internal) {
          escape = 2 * ngx_escape_uri(NULL, r->uri.data + loc_len,
                                      r->uri.len - loc_len, NGX_ESCAPE_URI);
      } else {
          escape = 0;
      }
  
      len = ctx->vars.uri.len + r->uri.len - loc_len + escape
            + sizeof("?") - 1 + r->args.len;
  
      p = ngx_pnalloc(r->pool, len);
      if (p == NULL) {
          return NGX_ERROR;
      }
  
      key->data = p;
  
      if (r->valid_location) {
          p = ngx_copy(p, ctx->vars.uri.data, ctx->vars.uri.len);
      }
  
      if (escape) {
          ngx_escape_uri(p, r->uri.data + loc_len,
                         r->uri.len - loc_len, NGX_ESCAPE_URI);
          p += r->uri.len - loc_len + escape;
  
      } else {
          p = ngx_copy(p, r->uri.data + loc_len, r->uri.len - loc_len);
      }
  
      if (r->args.len > 0) {
          *p++ = '?';
          p = ngx_copy(p, r->args.data, r->args.len);
      }
  
      key->len = p - key->data;
      u->uri = *key;
  
      return NGX_OK;
  }
  
  #endif
  
  
  static ngx_int_t
  ngx_http_proxy_create_request(ngx_http_request_t *r)
  {
      size_t                        len, uri_len, loc_len, body_len,
                                    key_len, val_len;
      uintptr_t                     escape;
      ngx_buf_t                    *b;
      ngx_str_t                     method;
      ngx_uint_t                    i, unparsed_uri;
      ngx_chain_t                  *cl, *body;
      ngx_list_part_t              *part;
      ngx_table_elt_t              *header;
      ngx_http_upstream_t          *u;
      ngx_http_proxy_ctx_t         *ctx;
      ngx_http_script_code_pt       code;
      ngx_http_proxy_headers_t     *headers;
      ngx_http_script_engine_t      e, le;
      ngx_http_proxy_loc_conf_t    *plcf;
      ngx_http_script_len_code_pt   lcode;
  
      u = r->upstream;
  
      plcf = ngx_http_get_module_loc_conf(r, ngx_http_proxy_module);
  
  #if (NGX_HTTP_CACHE)
      headers = u->cacheable ? &plcf->headers_cache : &plcf->headers;
  #else
      headers = &plcf->headers;
  #endif
  
      if (u->method.len) {
          /* HEAD was changed to GET to cache response */
          method = u->method;
  
      } else if (plcf->method) {
          if (ngx_http_complex_value(r, plcf->method, &method) != NGX_OK) {
              return NGX_ERROR;
          }
  
      } else {
          method = r->method_name;
      }
  
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      if (method.len == 4
          && ngx_strncasecmp(method.data, (u_char *) "HEAD", 4) == 0)
      {
          ctx->head = 1;
      }
  
      len = method.len + 1 + sizeof(ngx_http_proxy_version) - 1
            + sizeof(CRLF) - 1;
  
      escape = 0;
      loc_len = 0;
      unparsed_uri = 0;
  
      if (plcf->proxy_lengths && ctx->vars.uri.len) {
          uri_len = ctx->vars.uri.len;
  
      } else if (ctx->vars.uri.len == 0 && r->valid_unparsed_uri && r == r->main)
      {
          unparsed_uri = 1;
          uri_len = r->unparsed_uri.len;
  
      } else {
          loc_len = (r->valid_location && ctx->vars.uri.len) ?
                        plcf->location.len : 0;
  
          if (r->quoted_uri || r->space_in_uri || r->internal) {
              escape = 2 * ngx_escape_uri(NULL, r->uri.data + loc_len,
                                          r->uri.len - loc_len, NGX_ESCAPE_URI);
          }
  
          uri_len = ctx->vars.uri.len + r->uri.len - loc_len + escape
                    + sizeof("?") - 1 + r->args.len;
      }
  
      if (uri_len == 0) {
          ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                        "zero length URI to proxy");
          return NGX_ERROR;
      }
  
      len += uri_len;
  
      ngx_memzero(&le, sizeof(ngx_http_script_engine_t));
  
      ngx_http_script_flush_no_cacheable_variables(r, plcf->body_flushes);
      ngx_http_script_flush_no_cacheable_variables(r, headers->flushes);
  
      if (plcf->body_lengths) {
          le.ip = plcf->body_lengths->elts;
          le.request = r;
          le.flushed = 1;
          body_len = 0;
  
          while (*(uintptr_t *) le.ip) {
              lcode = *(ngx_http_script_len_code_pt *) le.ip;
              body_len += lcode(&le);
          }
  
          ctx->internal_body_length = body_len;
          len += body_len;
  
      } else if (r->headers_in.chunked && r->reading_body) {
          ctx->internal_body_length = -1;
          ctx->internal_chunked = 1;
  
      } else {
          ctx->internal_body_length = r->headers_in.content_length_n;
      }
  
      le.ip = headers->lengths->elts;
      le.request = r;
      le.flushed = 1;
  
      while (*(uintptr_t *) le.ip) {
  
          lcode = *(ngx_http_script_len_code_pt *) le.ip;
          key_len = lcode(&le);
  
          for (val_len = 0; *(uintptr_t *) le.ip; val_len += lcode(&le)) {
              lcode = *(ngx_http_script_len_code_pt *) le.ip;
          }
          le.ip += sizeof(uintptr_t);
  
          if (val_len == 0) {
              continue;
          }
  
          len += key_len + sizeof(": ") - 1 + val_len + sizeof(CRLF) - 1;
      }
  
  
      if (plcf->upstream.pass_request_headers) {
          part = &r->headers_in.headers.part;
          header = part->elts;
  
          for (i = 0; /* void */; i++) {
  
              if (i >= part->nelts) {
                  if (part->next == NULL) {
                      break;
                  }
  
                  part = part->next;
                  header = part->elts;
                  i = 0;
              }
  
              if (ngx_hash_find(&headers->hash, header[i].hash,
                                header[i].lowcase_key, header[i].key.len))
              {
                  continue;
              }
  
              len += header[i].key.len + sizeof(": ") - 1
                  + header[i].value.len + sizeof(CRLF) - 1;
          }
      }
  
  
      b = ngx_create_temp_buf(r->pool, len);
      if (b == NULL) {
          return NGX_ERROR;
      }
  
      cl = ngx_alloc_chain_link(r->pool);
      if (cl == NULL) {
          return NGX_ERROR;
      }
  
      cl->buf = b;
  
  
      /* the request line */
  
      b->last = ngx_copy(b->last, method.data, method.len);
      *b->last++ = ' ';
  
      u->uri.data = b->last;
  
      if (plcf->proxy_lengths && ctx->vars.uri.len) {
          b->last = ngx_copy(b->last, ctx->vars.uri.data, ctx->vars.uri.len);
  
      } else if (unparsed_uri) {
          b->last = ngx_copy(b->last, r->unparsed_uri.data, r->unparsed_uri.len);
  
      } else {
          if (r->valid_location) {
              b->last = ngx_copy(b->last, ctx->vars.uri.data, ctx->vars.uri.len);
          }
  
          if (escape) {
              ngx_escape_uri(b->last, r->uri.data + loc_len,
                             r->uri.len - loc_len, NGX_ESCAPE_URI);
              b->last += r->uri.len - loc_len + escape;
  
          } else {
              b->last = ngx_copy(b->last, r->uri.data + loc_len,
                                 r->uri.len - loc_len);
          }
  
          if (r->args.len > 0) {
              *b->last++ = '?';
              b->last = ngx_copy(b->last, r->args.data, r->args.len);
          }
      }
  
      u->uri.len = b->last - u->uri.data;
  
      if (plcf->http_version == NGX_HTTP_VERSION_11) {
          b->last = ngx_cpymem(b->last, ngx_http_proxy_version_11,
                               sizeof(ngx_http_proxy_version_11) - 1);
  
      } else {
          b->last = ngx_cpymem(b->last, ngx_http_proxy_version,
                               sizeof(ngx_http_proxy_version) - 1);
      }
  
      ngx_memzero(&e, sizeof(ngx_http_script_engine_t));
  
      e.ip = headers->values->elts;
      e.pos = b->last;
      e.request = r;
      e.flushed = 1;
  
      le.ip = headers->lengths->elts;
  
      while (*(uintptr_t *) le.ip) {
  
          lcode = *(ngx_http_script_len_code_pt *) le.ip;
          (void) lcode(&le);
  
          for (val_len = 0; *(uintptr_t *) le.ip; val_len += lcode(&le)) {
              lcode = *(ngx_http_script_len_code_pt *) le.ip;
          }
          le.ip += sizeof(uintptr_t);
  
          if (val_len == 0) {
              e.skip = 1;
  
              while (*(uintptr_t *) e.ip) {
                  code = *(ngx_http_script_code_pt *) e.ip;
                  code((ngx_http_script_engine_t *) &e);
              }
              e.ip += sizeof(uintptr_t);
  
              e.skip = 0;
  
              continue;
          }
  
          code = *(ngx_http_script_code_pt *) e.ip;
          code((ngx_http_script_engine_t *) &e);
  
          *e.pos++ = ':'; *e.pos++ = ' ';
  
          while (*(uintptr_t *) e.ip) {
              code = *(ngx_http_script_code_pt *) e.ip;
              code((ngx_http_script_engine_t *) &e);
          }
          e.ip += sizeof(uintptr_t);
  
          *e.pos++ = CR; *e.pos++ = LF;
      }
  
      b->last = e.pos;
  
  
      if (plcf->upstream.pass_request_headers) {
          part = &r->headers_in.headers.part;
          header = part->elts;
  
          for (i = 0; /* void */; i++) {
  
              if (i >= part->nelts) {
                  if (part->next == NULL) {
                      break;
                  }
  
                  part = part->next;
                  header = part->elts;
                  i = 0;
              }
  
              if (ngx_hash_find(&headers->hash, header[i].hash,
                                header[i].lowcase_key, header[i].key.len))
              {
                  continue;
              }
  
              b->last = ngx_copy(b->last, header[i].key.data, header[i].key.len);
  
              *b->last++ = ':'; *b->last++ = ' ';
  
              b->last = ngx_copy(b->last, header[i].value.data,
                                 header[i].value.len);
  
              *b->last++ = CR; *b->last++ = LF;
  
              ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                             "http proxy header: \"%V: %V\"",
                             &header[i].key, &header[i].value);
          }
      }
  
  
      /* add "\r\n" at the header end */
      *b->last++ = CR; *b->last++ = LF;
  
      if (plcf->body_values) {
          e.ip = plcf->body_values->elts;
          e.pos = b->last;
          e.skip = 0;
  
          while (*(uintptr_t *) e.ip) {
              code = *(ngx_http_script_code_pt *) e.ip;
              code((ngx_http_script_engine_t *) &e);
          }
  
          b->last = e.pos;
      }
  
      ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                     "http proxy header:%N\"%*s\"",
                     (size_t) (b->last - b->pos), b->pos);
  
      if (r->request_body_no_buffering) {
  
          u->request_bufs = cl;
  
          if (ctx->internal_chunked) {
              u->output.output_filter = ngx_http_proxy_body_output_filter;
              u->output.filter_ctx = r;
          }
  
      } else if (plcf->body_values == NULL && plcf->upstream.pass_request_body) {
  
          body = u->request_bufs;
          u->request_bufs = cl;
  
          while (body) {
              b = ngx_alloc_buf(r->pool);
              if (b == NULL) {
                  return NGX_ERROR;
              }
  
              ngx_memcpy(b, body->buf, sizeof(ngx_buf_t));
  
              cl->next = ngx_alloc_chain_link(r->pool);
              if (cl->next == NULL) {
                  return NGX_ERROR;
              }
  
              cl = cl->next;
              cl->buf = b;
  
              body = body->next;
          }
  
      } else {
          u->request_bufs = cl;
      }
  
      b->flush = 1;
      cl->next = NULL;
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_reinit_request(ngx_http_request_t *r)
  {
      ngx_http_proxy_ctx_t  *ctx;
  
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      if (ctx == NULL) {
          return NGX_OK;
      }
  
      ctx->status.code = 0;
      ctx->status.count = 0;
      ctx->status.start = NULL;
      ctx->status.end = NULL;
      ctx->chunked.state = 0;
  
      r->upstream->process_header = ngx_http_proxy_process_status_line;
      r->upstream->pipe->input_filter = ngx_http_proxy_copy_filter;
      r->upstream->input_filter = ngx_http_proxy_non_buffered_copy_filter;
      r->state = 0;
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_body_output_filter(void *data, ngx_chain_t *in)
  {
      ngx_http_request_t  *r = data;
  
      off_t                  size;
      u_char                *chunk;
      ngx_int_t              rc;
      ngx_buf_t             *b;
      ngx_chain_t           *out, *cl, *tl, **ll, **fl;
      ngx_http_proxy_ctx_t  *ctx;
  
      ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                     "proxy output filter");
  
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      if (in == NULL) {
          out = in;
          goto out;
      }
  
      out = NULL;
      ll = &out;
  
      if (!ctx->header_sent) {
          /* first buffer contains headers, pass it unmodified */
  
          ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                         "proxy output header");
  
          ctx->header_sent = 1;
  
          tl = ngx_alloc_chain_link(r->pool);
          if (tl == NULL) {
              return NGX_ERROR;
          }
  
          tl->buf = in->buf;
          *ll = tl;
          ll = &tl->next;
  
          in = in->next;
  
          if (in == NULL) {
              tl->next = NULL;
              goto out;
          }
      }
  
      size = 0;
      cl = in;
      fl = ll;
  
      for ( ;; ) {
          ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                         "proxy output chunk: %O", ngx_buf_size(cl->buf));
  
          size += ngx_buf_size(cl->buf);
  
          if (cl->buf->flush
              || cl->buf->sync
              || ngx_buf_in_memory(cl->buf)
              || cl->buf->in_file)
          {
              tl = ngx_alloc_chain_link(r->pool);
              if (tl == NULL) {
                  return NGX_ERROR;
              }
  
              tl->buf = cl->buf;
              *ll = tl;
              ll = &tl->next;
          }
  
          if (cl->next == NULL) {
              break;
          }
  
          cl = cl->next;
      }
  
      if (size) {
          tl = ngx_chain_get_free_buf(r->pool, &ctx->free);
          if (tl == NULL) {
              return NGX_ERROR;
          }
  
          b = tl->buf;
          chunk = b->start;
  
          if (chunk == NULL) {
              /* the "0000000000000000" is 64-bit hexadecimal string */
  
              chunk = ngx_palloc(r->pool, sizeof("0000000000000000" CRLF) - 1);
              if (chunk == NULL) {
                  return NGX_ERROR;
              }
  
              b->start = chunk;
              b->end = chunk + sizeof("0000000000000000" CRLF) - 1;
          }
  
          b->tag = (ngx_buf_tag_t) &ngx_http_proxy_body_output_filter;
          b->memory = 0;
          b->temporary = 1;
          b->pos = chunk;
          b->last = ngx_sprintf(chunk, "%xO" CRLF, size);
  
          tl->next = *fl;
          *fl = tl;
      }
  
      if (cl->buf->last_buf) {
          tl = ngx_chain_get_free_buf(r->pool, &ctx->free);
          if (tl == NULL) {
              return NGX_ERROR;
          }
  
          b = tl->buf;
  
          b->tag = (ngx_buf_tag_t) &ngx_http_proxy_body_output_filter;
          b->temporary = 0;
          b->memory = 1;
          b->last_buf = 1;
          b->pos = (u_char *) CRLF "0" CRLF CRLF;
          b->last = b->pos + 7;
  
          cl->buf->last_buf = 0;
  
          *ll = tl;
  
          if (size == 0) {
              b->pos += 2;
          }
  
      } else if (size > 0) {
          tl = ngx_chain_get_free_buf(r->pool, &ctx->free);
          if (tl == NULL) {
              return NGX_ERROR;
          }
  
          b = tl->buf;
  
          b->tag = (ngx_buf_tag_t) &ngx_http_proxy_body_output_filter;
          b->temporary = 0;
          b->memory = 1;
          b->pos = (u_char *) CRLF;
          b->last = b->pos + 2;
  
          *ll = tl;
  
      } else {
          *ll = NULL;
      }
  
  out:
  
      rc = ngx_chain_writer(&r->upstream->writer, out);
  
      ngx_chain_update_chains(r->pool, &ctx->free, &ctx->busy, &out,
                              (ngx_buf_tag_t) &ngx_http_proxy_body_output_filter);
  
      return rc;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_process_status_line(ngx_http_request_t *r)
  {
      size_t                 len;
      ngx_int_t              rc;
      ngx_http_upstream_t   *u;
      ngx_http_proxy_ctx_t  *ctx;
  
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      if (ctx == NULL) {
          return NGX_ERROR;
      }
  
      u = r->upstream;
  
      rc = ngx_http_parse_status_line(r, &u->buffer, &ctx->status);
  
      if (rc == NGX_AGAIN) {
          return rc;
      }
  
      if (rc == NGX_ERROR) {
  
  #if (NGX_HTTP_CACHE)
  
          if (r->cache) {
              r->http_version = NGX_HTTP_VERSION_9;
              return NGX_OK;
          }
  
  #endif
  
          ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                        "upstream sent no valid HTTP/1.0 header");
  
  #if 0
          if (u->accel) {
              return NGX_HTTP_UPSTREAM_INVALID_HEADER;
          }
  #endif
  
          r->http_version = NGX_HTTP_VERSION_9;
          u->state->status = NGX_HTTP_OK;
          u->headers_in.connection_close = 1;
  
          return NGX_OK;
      }
  
      if (u->state && u->state->status == 0) {
          u->state->status = ctx->status.code;
      }
  
      u->headers_in.status_n = ctx->status.code;
  
      len = ctx->status.end - ctx->status.start;
      u->headers_in.status_line.len = len;
  
      u->headers_in.status_line.data = ngx_pnalloc(r->pool, len);
      if (u->headers_in.status_line.data == NULL) {
          return NGX_ERROR;
      }
  
      ngx_memcpy(u->headers_in.status_line.data, ctx->status.start, len);
  
      ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                     "http proxy status %ui \"%V\"",
                     u->headers_in.status_n, &u->headers_in.status_line);
  
      if (ctx->status.http_version < NGX_HTTP_VERSION_11) {
          u->headers_in.connection_close = 1;
      }
  
      u->process_header = ngx_http_proxy_process_header;
  
      return ngx_http_proxy_process_header(r);
  }
  
  
  static ngx_int_t
  ngx_http_proxy_process_header(ngx_http_request_t *r)
  {
      ngx_int_t                       rc;
      ngx_table_elt_t                *h;
      ngx_http_upstream_t            *u;
      ngx_http_proxy_ctx_t           *ctx;
      ngx_http_upstream_header_t     *hh;
      ngx_http_upstream_main_conf_t  *umcf;
  
      umcf = ngx_http_get_module_main_conf(r, ngx_http_upstream_module);
  
      for ( ;; ) {
  
          rc = ngx_http_parse_header_line(r, &r->upstream->buffer, 1);
  
          if (rc == NGX_OK) {
  
              /* a header line has been parsed successfully */
  
              h = ngx_list_push(&r->upstream->headers_in.headers);
              if (h == NULL) {
                  return NGX_ERROR;
              }
  
              h->hash = r->header_hash;
  
              h->key.len = r->header_name_end - r->header_name_start;
              h->value.len = r->header_end - r->header_start;
  
              h->key.data = ngx_pnalloc(r->pool,
                                 h->key.len + 1 + h->value.len + 1 + h->key.len);
              if (h->key.data == NULL) {
                  h->hash = 0;
                  return NGX_ERROR;
              }
  
              h->value.data = h->key.data + h->key.len + 1;
              h->lowcase_key = h->key.data + h->key.len + 1 + h->value.len + 1;
  
              ngx_memcpy(h->key.data, r->header_name_start, h->key.len);
              h->key.data[h->key.len] = '\0';
              ngx_memcpy(h->value.data, r->header_start, h->value.len);
              h->value.data[h->value.len] = '\0';
  
              if (h->key.len == r->lowcase_index) {
                  ngx_memcpy(h->lowcase_key, r->lowcase_header, h->key.len);
  
              } else {
                  ngx_strlow(h->lowcase_key, h->key.data, h->key.len);
              }
  
              hh = ngx_hash_find(&umcf->headers_in_hash, h->hash,
                                 h->lowcase_key, h->key.len);
  
              if (hh && hh->handler(r, h, hh->offset) != NGX_OK) {
                  return NGX_ERROR;
              }
  
              ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                             "http proxy header: \"%V: %V\"",
                             &h->key, &h->value);
  
              continue;
          }
  
          if (rc == NGX_HTTP_PARSE_HEADER_DONE) {
  
              /* a whole header has been parsed successfully */
  
              ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                             "http proxy header done");
  
              /*
               * if no "Server" and "Date" in header line,
               * then add the special empty headers
               */
  
              if (r->upstream->headers_in.server == NULL) {
                  h = ngx_list_push(&r->upstream->headers_in.headers);
                  if (h == NULL) {
                      return NGX_ERROR;
                  }
  
                  h->hash = ngx_hash(ngx_hash(ngx_hash(ngx_hash(
                                      ngx_hash('s', 'e'), 'r'), 'v'), 'e'), 'r');
  
                  ngx_str_set(&h->key, "Server");
                  ngx_str_null(&h->value);
                  h->lowcase_key = (u_char *) "server";
              }
  
              if (r->upstream->headers_in.date == NULL) {
                  h = ngx_list_push(&r->upstream->headers_in.headers);
                  if (h == NULL) {
                      return NGX_ERROR;
                  }
  
                  h->hash = ngx_hash(ngx_hash(ngx_hash('d', 'a'), 't'), 'e');
  
                  ngx_str_set(&h->key, "Date");
                  ngx_str_null(&h->value);
                  h->lowcase_key = (u_char *) "date";
              }
  
              /* clear content length if response is chunked */
  
              u = r->upstream;
  
              if (u->headers_in.chunked) {
                  u->headers_in.content_length_n = -1;
              }
  
              /*
               * set u->keepalive if response has no body; this allows to keep
               * connections alive in case of r->header_only or X-Accel-Redirect
               */
  
              ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
              if (u->headers_in.status_n == NGX_HTTP_NO_CONTENT
                  || u->headers_in.status_n == NGX_HTTP_NOT_MODIFIED
                  || ctx->head
                  || (!u->headers_in.chunked
                      && u->headers_in.content_length_n == 0))
              {
                  u->keepalive = !u->headers_in.connection_close;
              }
  
              if (u->headers_in.status_n == NGX_HTTP_SWITCHING_PROTOCOLS) {
                  u->keepalive = 0;
  
                  if (r->headers_in.upgrade) {
                      u->upgrade = 1;
                  }
              }
  
              return NGX_OK;
          }
  
          if (rc == NGX_AGAIN) {
              return NGX_AGAIN;
          }
  
          /* there was error while a header line parsing */
  
          ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                        "upstream sent invalid header");
  
          return NGX_HTTP_UPSTREAM_INVALID_HEADER;
      }
  }
  
  
  static ngx_int_t
  ngx_http_proxy_input_filter_init(void *data)
  {
      ngx_http_request_t    *r = data;
      ngx_http_upstream_t   *u;
      ngx_http_proxy_ctx_t  *ctx;
  
      u = r->upstream;
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      if (ctx == NULL) {
          return NGX_ERROR;
      }
  
      ngx_log_debug4(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                     "http proxy filter init s:%ui h:%d c:%d l:%O",
                     u->headers_in.status_n, ctx->head, u->headers_in.chunked,
                     u->headers_in.content_length_n);
  
      /* as per RFC2616, 4.4 Message Length */
  
      if (u->headers_in.status_n == NGX_HTTP_NO_CONTENT
          || u->headers_in.status_n == NGX_HTTP_NOT_MODIFIED
          || ctx->head)
      {
          /* 1xx, 204, and 304 and replies to HEAD requests */
          /* no 1xx since we don't send Expect and Upgrade */
  
          u->pipe->length = 0;
          u->length = 0;
          u->keepalive = !u->headers_in.connection_close;
  
      } else if (u->headers_in.chunked) {
          /* chunked */
  
          u->pipe->input_filter = ngx_http_proxy_chunked_filter;
          u->pipe->length = 3; /* "0" LF LF */
  
          u->input_filter = ngx_http_proxy_non_buffered_chunked_filter;
          u->length = 1;
  
      } else if (u->headers_in.content_length_n == 0) {
          /* empty body: special case as filter won't be called */
  
          u->pipe->length = 0;
          u->length = 0;
          u->keepalive = !u->headers_in.connection_close;
  
      } else {
          /* content length or connection close */
  
          u->pipe->length = u->headers_in.content_length_n;
          u->length = u->headers_in.content_length_n;
      }
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_copy_filter(ngx_event_pipe_t *p, ngx_buf_t *buf)
  {
      ngx_buf_t           *b;
      ngx_chain_t         *cl;
      ngx_http_request_t  *r;
  
      if (buf->pos == buf->last) {
          return NGX_OK;
      }
  
      cl = ngx_chain_get_free_buf(p->pool, &p->free);
      if (cl == NULL) {
          return NGX_ERROR;
      }
  
      b = cl->buf;
  
      ngx_memcpy(b, buf, sizeof(ngx_buf_t));
      b->shadow = buf;
      b->tag = p->tag;
      b->last_shadow = 1;
      b->recycled = 1;
      buf->shadow = b;
  
      ngx_log_debug1(NGX_LOG_DEBUG_EVENT, p->log, 0, "input buf #%d", b->num);
  
      if (p->in) {
          *p->last_in = cl;
      } else {
          p->in = cl;
      }
      p->last_in = &cl->next;
  
      if (p->length == -1) {
          return NGX_OK;
      }
  
      p->length -= b->last - b->pos;
  
      if (p->length == 0) {
          r = p->input_ctx;
          p->upstream_done = 1;
          r->upstream->keepalive = !r->upstream->headers_in.connection_close;
  
      } else if (p->length < 0) {
          r = p->input_ctx;
          p->upstream_done = 1;
  
          ngx_log_error(NGX_LOG_WARN, r->connection->log, 0,
                        "upstream sent more data than specified in "
                        "\"Content-Length\" header");
      }
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_chunked_filter(ngx_event_pipe_t *p, ngx_buf_t *buf)
  {
      ngx_int_t              rc;
      ngx_buf_t             *b, **prev;
      ngx_chain_t           *cl;
      ngx_http_request_t    *r;
      ngx_http_proxy_ctx_t  *ctx;
  
      if (buf->pos == buf->last) {
          return NGX_OK;
      }
  
      r = p->input_ctx;
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      if (ctx == NULL) {
          return NGX_ERROR;
      }
  
      b = NULL;
      prev = &buf->shadow;
  
      for ( ;; ) {
  
          rc = ngx_http_parse_chunked(r, buf, &ctx->chunked);
  
          if (rc == NGX_OK) {
  
              /* a chunk has been parsed successfully */
  
              cl = ngx_chain_get_free_buf(p->pool, &p->free);
              if (cl == NULL) {
                  return NGX_ERROR;
              }
  
              b = cl->buf;
  
              ngx_memzero(b, sizeof(ngx_buf_t));
  
              b->pos = buf->pos;
              b->start = buf->start;
              b->end = buf->end;
              b->tag = p->tag;
              b->temporary = 1;
              b->recycled = 1;
  
              *prev = b;
              prev = &b->shadow;
  
              if (p->in) {
                  *p->last_in = cl;
              } else {
                  p->in = cl;
              }
              p->last_in = &cl->next;
  
              /* STUB */ b->num = buf->num;
  
              ngx_log_debug2(NGX_LOG_DEBUG_EVENT, p->log, 0,
                             "input buf #%d %p", b->num, b->pos);
  
              if (buf->last - buf->pos >= ctx->chunked.size) {
  
                  buf->pos += (size_t) ctx->chunked.size;
                  b->last = buf->pos;
                  ctx->chunked.size = 0;
  
                  continue;
              }
  
              ctx->chunked.size -= buf->last - buf->pos;
              buf->pos = buf->last;
              b->last = buf->last;
  
              continue;
          }
  
          if (rc == NGX_DONE) {
  
              /* a whole response has been parsed successfully */
  
              p->upstream_done = 1;
              r->upstream->keepalive = !r->upstream->headers_in.connection_close;
  
              break;
          }
  
          if (rc == NGX_AGAIN) {
  
              /* set p->length, minimal amount of data we want to see */
  
              p->length = ctx->chunked.length;
  
              break;
          }
  
          /* invalid response */
  
          ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                        "upstream sent invalid chunked response");
  
          return NGX_ERROR;
      }
  
      ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                     "http proxy chunked state %ui, length %O",
                     ctx->chunked.state, p->length);
  
      if (b) {
          b->shadow = buf;
          b->last_shadow = 1;
  
          ngx_log_debug2(NGX_LOG_DEBUG_EVENT, p->log, 0,
                         "input buf %p %z", b->pos, b->last - b->pos);
  
          return NGX_OK;
      }
  
      /* there is no data record in the buf, add it to free chain */
  
      if (ngx_event_pipe_add_free_buf(p, buf) != NGX_OK) {
          return NGX_ERROR;
      }
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_non_buffered_copy_filter(void *data, ssize_t bytes)
  {
      ngx_http_request_t   *r = data;
  
      ngx_buf_t            *b;
      ngx_chain_t          *cl, **ll;
      ngx_http_upstream_t  *u;
  
      u = r->upstream;
  
      for (cl = u->out_bufs, ll = &u->out_bufs; cl; cl = cl->next) {
          ll = &cl->next;
      }
  
      cl = ngx_chain_get_free_buf(r->pool, &u->free_bufs);
      if (cl == NULL) {
          return NGX_ERROR;
      }
  
      *ll = cl;
  
      cl->buf->flush = 1;
      cl->buf->memory = 1;
  
      b = &u->buffer;
  
      cl->buf->pos = b->last;
      b->last += bytes;
      cl->buf->last = b->last;
      cl->buf->tag = u->output.tag;
  
      if (u->length == -1) {
          return NGX_OK;
      }
  
      u->length -= bytes;
  
      if (u->length == 0) {
          u->keepalive = !u->headers_in.connection_close;
      }
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_non_buffered_chunked_filter(void *data, ssize_t bytes)
  {
      ngx_http_request_t   *r = data;
  
      ngx_int_t              rc;
      ngx_buf_t             *b, *buf;
      ngx_chain_t           *cl, **ll;
      ngx_http_upstream_t   *u;
      ngx_http_proxy_ctx_t  *ctx;
  
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      if (ctx == NULL) {
          return NGX_ERROR;
      }
  
      u = r->upstream;
      buf = &u->buffer;
  
      buf->pos = buf->last;
      buf->last += bytes;
  
      for (cl = u->out_bufs, ll = &u->out_bufs; cl; cl = cl->next) {
          ll = &cl->next;
      }
  
      for ( ;; ) {
  
          rc = ngx_http_parse_chunked(r, buf, &ctx->chunked);
  
          if (rc == NGX_OK) {
  
              /* a chunk has been parsed successfully */
  
              cl = ngx_chain_get_free_buf(r->pool, &u->free_bufs);
              if (cl == NULL) {
                  return NGX_ERROR;
              }
  
              *ll = cl;
              ll = &cl->next;
  
              b = cl->buf;
  
              b->flush = 1;
              b->memory = 1;
  
              b->pos = buf->pos;
              b->tag = u->output.tag;
  
              if (buf->last - buf->pos >= ctx->chunked.size) {
                  buf->pos += (size_t) ctx->chunked.size;
                  b->last = buf->pos;
                  ctx->chunked.size = 0;
  
              } else {
                  ctx->chunked.size -= buf->last - buf->pos;
                  buf->pos = buf->last;
                  b->last = buf->last;
              }
  
              ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                             "http proxy out buf %p %z",
                             b->pos, b->last - b->pos);
  
              continue;
          }
  
          if (rc == NGX_DONE) {
  
              /* a whole response has been parsed successfully */
  
              u->keepalive = !u->headers_in.connection_close;
              u->length = 0;
  
              break;
          }
  
          if (rc == NGX_AGAIN) {
              break;
          }
  
          /* invalid response */
  
          ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                        "upstream sent invalid chunked response");
  
          return NGX_ERROR;
      }
  
      /* provide continuous buffer for subrequests in memory */
  
      if (r->subrequest_in_memory) {
  
          cl = u->out_bufs;
  
          if (cl) {
              buf->pos = cl->buf->pos;
          }
  
          buf->last = buf->pos;
  
          for (cl = u->out_bufs; cl; cl = cl->next) {
              ngx_log_debug3(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                             "http proxy in memory %p-%p %O",
                             cl->buf->pos, cl->buf->last, ngx_buf_size(cl->buf));
  
              if (buf->last == cl->buf->pos) {
                  buf->last = cl->buf->last;
                  continue;
              }
  
              buf->last = ngx_movemem(buf->last, cl->buf->pos,
                                      cl->buf->last - cl->buf->pos);
  
              cl->buf->pos = buf->last - (cl->buf->last - cl->buf->pos);
              cl->buf->last = buf->last;
          }
      }
  
      return NGX_OK;
  }
  
  
  static void
  ngx_http_proxy_abort_request(ngx_http_request_t *r)
  {
      ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                     "abort http proxy request");
  
      return;
  }
  
  
  static void
  ngx_http_proxy_finalize_request(ngx_http_request_t *r, ngx_int_t rc)
  {
      ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                     "finalize http proxy request");
  
      return;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_host_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data)
  {
      ngx_http_proxy_ctx_t  *ctx;
  
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      if (ctx == NULL) {
          v->not_found = 1;
          return NGX_OK;
      }
  
      v->len = ctx->vars.host_header.len;
      v->valid = 1;
      v->no_cacheable = 0;
      v->not_found = 0;
      v->data = ctx->vars.host_header.data;
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_port_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data)
  {
      ngx_http_proxy_ctx_t  *ctx;
  
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      if (ctx == NULL) {
          v->not_found = 1;
          return NGX_OK;
      }
  
      v->len = ctx->vars.port.len;
      v->valid = 1;
      v->no_cacheable = 0;
      v->not_found = 0;
      v->data = ctx->vars.port.data;
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_add_x_forwarded_for_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data)
  {
      size_t             len;
      u_char            *p;
      ngx_uint_t         i, n;
      ngx_table_elt_t  **h;
  
      v->valid = 1;
      v->no_cacheable = 0;
      v->not_found = 0;
  
      n = r->headers_in.x_forwarded_for.nelts;
      h = r->headers_in.x_forwarded_for.elts;
  
      len = 0;
  
      for (i = 0; i < n; i++) {
          len += h[i]->value.len + sizeof(", ") - 1;
      }
  
      if (len == 0) {
          v->len = r->connection->addr_text.len;
          v->data = r->connection->addr_text.data;
          return NGX_OK;
      }
  
      len += r->connection->addr_text.len;
  
      p = ngx_pnalloc(r->pool, len);
      if (p == NULL) {
          return NGX_ERROR;
      }
  
      v->len = len;
      v->data = p;
  
      for (i = 0; i < n; i++) {
          p = ngx_copy(p, h[i]->value.data, h[i]->value.len);
          *p++ = ','; *p++ = ' ';
      }
  
      ngx_memcpy(p, r->connection->addr_text.data, r->connection->addr_text.len);
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_internal_body_length_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data)
  {
      ngx_http_proxy_ctx_t  *ctx;
  
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      if (ctx == NULL || ctx->internal_body_length < 0) {
          v->not_found = 1;
          return NGX_OK;
      }
  
      v->valid = 1;
      v->no_cacheable = 0;
      v->not_found = 0;
  
      v->data = ngx_pnalloc(r->pool, NGX_OFF_T_LEN);
  
      if (v->data == NULL) {
          return NGX_ERROR;
      }
  
      v->len = ngx_sprintf(v->data, "%O", ctx->internal_body_length) - v->data;
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_internal_chunked_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data)
  {
      ngx_http_proxy_ctx_t  *ctx;
  
      ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);
  
      if (ctx == NULL || !ctx->internal_chunked) {
          v->not_found = 1;
          return NGX_OK;
      }
  
      v->valid = 1;
      v->no_cacheable = 0;
      v->not_found = 0;
  
      v->data = (u_char *) "chunked";
      v->len = sizeof("chunked") - 1;
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_rewrite_redirect(ngx_http_request_t *r, ngx_table_elt_t *h,
      size_t prefix)
  {
      size_t                      len;
      ngx_int_t                   rc;
      ngx_uint_t                  i;
      ngx_http_proxy_rewrite_t   *pr;
      ngx_http_proxy_loc_conf_t  *plcf;
  
      plcf = ngx_http_get_module_loc_conf(r, ngx_http_proxy_module);
  
      pr = plcf->redirects->elts;
  
      if (pr == NULL) {
          return NGX_DECLINED;
      }
  
      len = h->value.len - prefix;
  
      for (i = 0; i < plcf->redirects->nelts; i++) {
          rc = pr[i].handler(r, h, prefix, len, &pr[i]);
  
          if (rc != NGX_DECLINED) {
              return rc;
          }
      }
  
      return NGX_DECLINED;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_rewrite_cookie(ngx_http_request_t *r, ngx_table_elt_t *h)
  {
      size_t                      prefix;
      u_char                     *p;
      ngx_int_t                   rc, rv;
      ngx_http_proxy_loc_conf_t  *plcf;
  
      p = (u_char *) ngx_strchr(h->value.data, ';');
      if (p == NULL) {
          return NGX_DECLINED;
      }
  
      prefix = p + 1 - h->value.data;
  
      rv = NGX_DECLINED;
  
      plcf = ngx_http_get_module_loc_conf(r, ngx_http_proxy_module);
  
      if (plcf->cookie_domains) {
          p = ngx_strcasestrn(h->value.data + prefix, "domain=", 7 - 1);
  
          if (p) {
              rc = ngx_http_proxy_rewrite_cookie_value(r, h, p + 7,
                                                       plcf->cookie_domains);
              if (rc == NGX_ERROR) {
                  return NGX_ERROR;
              }
  
              if (rc != NGX_DECLINED) {
                  rv = rc;
              }
          }
      }
  
      if (plcf->cookie_paths) {
          p = ngx_strcasestrn(h->value.data + prefix, "path=", 5 - 1);
  
          if (p) {
              rc = ngx_http_proxy_rewrite_cookie_value(r, h, p + 5,
                                                       plcf->cookie_paths);
              if (rc == NGX_ERROR) {
                  return NGX_ERROR;
              }
  
              if (rc != NGX_DECLINED) {
                  rv = rc;
              }
          }
      }
  
      return rv;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_rewrite_cookie_value(ngx_http_request_t *r, ngx_table_elt_t *h,
      u_char *value, ngx_array_t *rewrites)
  {
      size_t                     len, prefix;
      u_char                    *p;
      ngx_int_t                  rc;
      ngx_uint_t                 i;
      ngx_http_proxy_rewrite_t  *pr;
  
      prefix = value - h->value.data;
  
      p = (u_char *) ngx_strchr(value, ';');
  
      len = p ? (size_t) (p - value) : (h->value.len - prefix);
  
      pr = rewrites->elts;
  
      for (i = 0; i < rewrites->nelts; i++) {
          rc = pr[i].handler(r, h, prefix, len, &pr[i]);
  
          if (rc != NGX_DECLINED) {
              return rc;
          }
      }
  
      return NGX_DECLINED;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_rewrite_complex_handler(ngx_http_request_t *r,
      ngx_table_elt_t *h, size_t prefix, size_t len, ngx_http_proxy_rewrite_t *pr)
  {
      ngx_str_t  pattern, replacement;
  
      if (ngx_http_complex_value(r, &pr->pattern.complex, &pattern) != NGX_OK) {
          return NGX_ERROR;
      }
  
      if (pattern.len > len
          || ngx_rstrncmp(h->value.data + prefix, pattern.data,
                          pattern.len) != 0)
      {
          return NGX_DECLINED;
      }
  
      if (ngx_http_complex_value(r, &pr->replacement, &replacement) != NGX_OK) {
          return NGX_ERROR;
      }
  
      return ngx_http_proxy_rewrite(r, h, prefix, pattern.len, &replacement);
  }
  
  
  #if (NGX_PCRE)
  
  static ngx_int_t
  ngx_http_proxy_rewrite_regex_handler(ngx_http_request_t *r, ngx_table_elt_t *h,
      size_t prefix, size_t len, ngx_http_proxy_rewrite_t *pr)
  {
      ngx_str_t  pattern, replacement;
  
      pattern.len = len;
      pattern.data = h->value.data + prefix;
  
      if (ngx_http_regex_exec(r, pr->pattern.regex, &pattern) != NGX_OK) {
          return NGX_DECLINED;
      }
  
      if (ngx_http_complex_value(r, &pr->replacement, &replacement) != NGX_OK) {
          return NGX_ERROR;
      }
  
      if (prefix == 0 && h->value.len == len) {
          h->value = replacement;
          return NGX_OK;
      }
  
      return ngx_http_proxy_rewrite(r, h, prefix, len, &replacement);
  }
  
  #endif
  
  
  static ngx_int_t
  ngx_http_proxy_rewrite_domain_handler(ngx_http_request_t *r,
      ngx_table_elt_t *h, size_t prefix, size_t len, ngx_http_proxy_rewrite_t *pr)
  {
      u_char     *p;
      ngx_str_t   pattern, replacement;
  
      if (ngx_http_complex_value(r, &pr->pattern.complex, &pattern) != NGX_OK) {
          return NGX_ERROR;
      }
  
      p = h->value.data + prefix;
  
      if (p[0] == '.') {
          p++;
          prefix++;
          len--;
      }
  
      if (pattern.len != len || ngx_rstrncasecmp(pattern.data, p, len) != 0) {
          return NGX_DECLINED;
      }
  
      if (ngx_http_complex_value(r, &pr->replacement, &replacement) != NGX_OK) {
          return NGX_ERROR;
      }
  
      return ngx_http_proxy_rewrite(r, h, prefix, len, &replacement);
  }
  
  
  static ngx_int_t
  ngx_http_proxy_rewrite(ngx_http_request_t *r, ngx_table_elt_t *h, size_t prefix,
      size_t len, ngx_str_t *replacement)
  {
      u_char  *p, *data;
      size_t   new_len;
  
      new_len = replacement->len + h->value.len - len;
  
      if (replacement->len > len) {
  
          data = ngx_pnalloc(r->pool, new_len + 1);
          if (data == NULL) {
              return NGX_ERROR;
          }
  
          p = ngx_copy(data, h->value.data, prefix);
          p = ngx_copy(p, replacement->data, replacement->len);
  
          ngx_memcpy(p, h->value.data + prefix + len,
                     h->value.len - len - prefix + 1);
  
          h->value.data = data;
  
      } else {
          p = ngx_copy(h->value.data + prefix, replacement->data,
                       replacement->len);
  
          ngx_memmove(p, h->value.data + prefix + len,
                      h->value.len - len - prefix + 1);
      }
  
      h->value.len = new_len;
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_add_variables(ngx_conf_t *cf)
  {
      ngx_http_variable_t  *var, *v;
  
      for (v = ngx_http_proxy_vars; v->name.len; v++) {
          var = ngx_http_add_variable(cf, &v->name, v->flags);
          if (var == NULL) {
              return NGX_ERROR;
          }
  
          var->get_handler = v->get_handler;
          var->data = v->data;
      }
  
      return NGX_OK;
  }
  
  
  static void *
  ngx_http_proxy_create_main_conf(ngx_conf_t *cf)
  {
      ngx_http_proxy_main_conf_t  *conf;
  
      conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_proxy_main_conf_t));
      if (conf == NULL) {
          return NULL;
      }
  
  #if (NGX_HTTP_CACHE)
      if (ngx_array_init(&conf->caches, cf->pool, 4,
                         sizeof(ngx_http_file_cache_t *))
          != NGX_OK)
      {
          return NULL;
      }
  #endif
  
      return conf;
  }
  
  
  static void *
  ngx_http_proxy_create_loc_conf(ngx_conf_t *cf)
  {
      ngx_http_proxy_loc_conf_t  *conf;
  
      conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_proxy_loc_conf_t));
      if (conf == NULL) {
          return NULL;
      }
  
      /*
       * set by ngx_pcalloc():
       *
       *     conf->upstream.bufs.num = 0;
       *     conf->upstream.ignore_headers = 0;
       *     conf->upstream.next_upstream = 0;
       *     conf->upstream.cache_zone = NULL;
       *     conf->upstream.cache_use_stale = 0;
       *     conf->upstream.cache_methods = 0;
       *     conf->upstream.temp_path = NULL;
       *     conf->upstream.hide_headers_hash = { NULL, 0 };
       *     conf->upstream.uri = { 0, NULL };
       *     conf->upstream.location = NULL;
       *     conf->upstream.store_lengths = NULL;
       *     conf->upstream.store_values = NULL;
       *     conf->upstream.ssl_name = NULL;
       *
       *     conf->method = NULL;
       *     conf->headers_source = NULL;
       *     conf->headers.lengths = NULL;
       *     conf->headers.values = NULL;
       *     conf->headers.hash = { NULL, 0 };
       *     conf->headers_cache.lengths = NULL;
       *     conf->headers_cache.values = NULL;
       *     conf->headers_cache.hash = { NULL, 0 };
       *     conf->body_lengths = NULL;
       *     conf->body_values = NULL;
       *     conf->body_source = { 0, NULL };
       *     conf->redirects = NULL;
       *     conf->ssl = 0;
       *     conf->ssl_protocols = 0;
       *     conf->ssl_ciphers = { 0, NULL };
       *     conf->ssl_trusted_certificate = { 0, NULL };
       *     conf->ssl_crl = { 0, NULL };
       *     conf->ssl_certificate = { 0, NULL };
       *     conf->ssl_certificate_key = { 0, NULL };
       */
  
      conf->upstream.store = NGX_CONF_UNSET;
      conf->upstream.store_access = NGX_CONF_UNSET_UINT;
      conf->upstream.next_upstream_tries = NGX_CONF_UNSET_UINT;
      conf->upstream.buffering = NGX_CONF_UNSET;
      conf->upstream.request_buffering = NGX_CONF_UNSET;
      conf->upstream.ignore_client_abort = NGX_CONF_UNSET;
      conf->upstream.force_ranges = NGX_CONF_UNSET;
  
      conf->upstream.local = NGX_CONF_UNSET_PTR;
  
      conf->upstream.connect_timeout = NGX_CONF_UNSET_MSEC;
      conf->upstream.send_timeout = NGX_CONF_UNSET_MSEC;
      conf->upstream.read_timeout = NGX_CONF_UNSET_MSEC;
      conf->upstream.next_upstream_timeout = NGX_CONF_UNSET_MSEC;
  
      conf->upstream.send_lowat = NGX_CONF_UNSET_SIZE;
      conf->upstream.buffer_size = NGX_CONF_UNSET_SIZE;
      conf->upstream.limit_rate = NGX_CONF_UNSET_SIZE;
  
      conf->upstream.busy_buffers_size_conf = NGX_CONF_UNSET_SIZE;
      conf->upstream.max_temp_file_size_conf = NGX_CONF_UNSET_SIZE;
      conf->upstream.temp_file_write_size_conf = NGX_CONF_UNSET_SIZE;
  
      conf->upstream.pass_request_headers = NGX_CONF_UNSET;
      conf->upstream.pass_request_body = NGX_CONF_UNSET;
  
  #if (NGX_HTTP_CACHE)
      conf->upstream.cache = NGX_CONF_UNSET;
      conf->upstream.cache_min_uses = NGX_CONF_UNSET_UINT;
      conf->upstream.cache_max_range_offset = NGX_CONF_UNSET;
      conf->upstream.cache_bypass = NGX_CONF_UNSET_PTR;
      conf->upstream.no_cache = NGX_CONF_UNSET_PTR;
      conf->upstream.cache_valid = NGX_CONF_UNSET_PTR;
      conf->upstream.cache_lock = NGX_CONF_UNSET;
      conf->upstream.cache_lock_timeout = NGX_CONF_UNSET_MSEC;
      conf->upstream.cache_lock_age = NGX_CONF_UNSET_MSEC;
      conf->upstream.cache_revalidate = NGX_CONF_UNSET;
      conf->upstream.cache_convert_head = NGX_CONF_UNSET;
      conf->upstream.cache_background_update = NGX_CONF_UNSET;
  #endif
  
      conf->upstream.hide_headers = NGX_CONF_UNSET_PTR;
      conf->upstream.pass_headers = NGX_CONF_UNSET_PTR;
  
      conf->upstream.intercept_errors = NGX_CONF_UNSET;
  
  #if (NGX_HTTP_SSL)
      conf->upstream.ssl_session_reuse = NGX_CONF_UNSET;
      conf->upstream.ssl_server_name = NGX_CONF_UNSET;
      conf->upstream.ssl_verify = NGX_CONF_UNSET;
      conf->ssl_verify_depth = NGX_CONF_UNSET_UINT;
      conf->ssl_passwords = NGX_CONF_UNSET_PTR;
  #endif
  
      /* "proxy_cyclic_temp_file" is disabled */
      conf->upstream.cyclic_temp_file = 0;
  
      conf->redirect = NGX_CONF_UNSET;
      conf->upstream.change_buffering = 1;
  
      conf->cookie_domains = NGX_CONF_UNSET_PTR;
      conf->cookie_paths = NGX_CONF_UNSET_PTR;
  
      conf->http_version = NGX_CONF_UNSET_UINT;
  
      conf->headers_hash_max_size = NGX_CONF_UNSET_UINT;
      conf->headers_hash_bucket_size = NGX_CONF_UNSET_UINT;
  
      ngx_str_set(&conf->upstream.module, "proxy");
  
      return conf;
  }
  
  
  static char *
  ngx_http_proxy_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
  {
      ngx_http_proxy_loc_conf_t *prev = parent;
      ngx_http_proxy_loc_conf_t *conf = child;
  
      u_char                     *p;
      size_t                      size;
      ngx_int_t                   rc;
      ngx_hash_init_t             hash;
      ngx_http_core_loc_conf_t   *clcf;
      ngx_http_proxy_rewrite_t   *pr;
      ngx_http_script_compile_t   sc;
  
  #if (NGX_HTTP_CACHE)
  
      if (conf->upstream.store > 0) {
          conf->upstream.cache = 0;
      }
  
      if (conf->upstream.cache > 0) {
          conf->upstream.store = 0;
      }
  
  #endif
  
      if (conf->upstream.store == NGX_CONF_UNSET) {
          ngx_conf_merge_value(conf->upstream.store,
                                prev->upstream.store, 0);
  
          conf->upstream.store_lengths = prev->upstream.store_lengths;
          conf->upstream.store_values = prev->upstream.store_values;
      }
  
      ngx_conf_merge_uint_value(conf->upstream.store_access,
                                prev->upstream.store_access, 0600);
  
      ngx_conf_merge_uint_value(conf->upstream.next_upstream_tries,
                                prev->upstream.next_upstream_tries, 0);
  
      ngx_conf_merge_value(conf->upstream.buffering,
                                prev->upstream.buffering, 1);
  
      ngx_conf_merge_value(conf->upstream.request_buffering,
                                prev->upstream.request_buffering, 1);
  
      ngx_conf_merge_value(conf->upstream.ignore_client_abort,
                                prev->upstream.ignore_client_abort, 0);
  
      ngx_conf_merge_value(conf->upstream.force_ranges,
                                prev->upstream.force_ranges, 0);
  
      ngx_conf_merge_ptr_value(conf->upstream.local,
                                prev->upstream.local, NULL);
  
      ngx_conf_merge_msec_value(conf->upstream.connect_timeout,
                                prev->upstream.connect_timeout, 60000);
  
      ngx_conf_merge_msec_value(conf->upstream.send_timeout,
                                prev->upstream.send_timeout, 60000);
  
      ngx_conf_merge_msec_value(conf->upstream.read_timeout,
                                prev->upstream.read_timeout, 60000);
  
      ngx_conf_merge_msec_value(conf->upstream.next_upstream_timeout,
                                prev->upstream.next_upstream_timeout, 0);
  
      ngx_conf_merge_size_value(conf->upstream.send_lowat,
                                prev->upstream.send_lowat, 0);
  
      ngx_conf_merge_size_value(conf->upstream.buffer_size,
                                prev->upstream.buffer_size,
                                (size_t) ngx_pagesize);
  
      ngx_conf_merge_size_value(conf->upstream.limit_rate,
                                prev->upstream.limit_rate, 0);
  
      ngx_conf_merge_bufs_value(conf->upstream.bufs, prev->upstream.bufs,
                                8, ngx_pagesize);
  
      if (conf->upstream.bufs.num < 2) {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "there must be at least 2 \"proxy_buffers\"");
          return NGX_CONF_ERROR;
      }
  
  
      size = conf->upstream.buffer_size;
      if (size < conf->upstream.bufs.size) {
          size = conf->upstream.bufs.size;
      }
  
  
      ngx_conf_merge_size_value(conf->upstream.busy_buffers_size_conf,
                                prev->upstream.busy_buffers_size_conf,
                                NGX_CONF_UNSET_SIZE);
  
      if (conf->upstream.busy_buffers_size_conf == NGX_CONF_UNSET_SIZE) {
          conf->upstream.busy_buffers_size = 2 * size;
      } else {
          conf->upstream.busy_buffers_size =
                                           conf->upstream.busy_buffers_size_conf;
      }
  
      if (conf->upstream.busy_buffers_size < size) {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
               "\"proxy_busy_buffers_size\" must be equal to or greater than "
               "the maximum of the value of \"proxy_buffer_size\" and "
               "one of the \"proxy_buffers\"");
  
          return NGX_CONF_ERROR;
      }
  
      if (conf->upstream.busy_buffers_size
          > (conf->upstream.bufs.num - 1) * conf->upstream.bufs.size)
      {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
               "\"proxy_busy_buffers_size\" must be less than "
               "the size of all \"proxy_buffers\" minus one buffer");
  
          return NGX_CONF_ERROR;
      }
  
  
      ngx_conf_merge_size_value(conf->upstream.temp_file_write_size_conf,
                                prev->upstream.temp_file_write_size_conf,
                                NGX_CONF_UNSET_SIZE);
  
      if (conf->upstream.temp_file_write_size_conf == NGX_CONF_UNSET_SIZE) {
          conf->upstream.temp_file_write_size = 2 * size;
      } else {
          conf->upstream.temp_file_write_size =
                                        conf->upstream.temp_file_write_size_conf;
      }
  
      if (conf->upstream.temp_file_write_size < size) {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
               "\"proxy_temp_file_write_size\" must be equal to or greater "
               "than the maximum of the value of \"proxy_buffer_size\" and "
               "one of the \"proxy_buffers\"");
  
          return NGX_CONF_ERROR;
      }
  
      ngx_conf_merge_size_value(conf->upstream.max_temp_file_size_conf,
                                prev->upstream.max_temp_file_size_conf,
                                NGX_CONF_UNSET_SIZE);
  
      if (conf->upstream.max_temp_file_size_conf == NGX_CONF_UNSET_SIZE) {
          conf->upstream.max_temp_file_size = 1024 * 1024 * 1024;
      } else {
          conf->upstream.max_temp_file_size =
                                          conf->upstream.max_temp_file_size_conf;
      }
  
      if (conf->upstream.max_temp_file_size != 0
          && conf->upstream.max_temp_file_size < size)
      {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
               "\"proxy_max_temp_file_size\" must be equal to zero to disable "
               "temporary files usage or must be equal to or greater than "
               "the maximum of the value of \"proxy_buffer_size\" and "
               "one of the \"proxy_buffers\"");
  
          return NGX_CONF_ERROR;
      }
  
  
      ngx_conf_merge_bitmask_value(conf->upstream.ignore_headers,
                                prev->upstream.ignore_headers,
                                NGX_CONF_BITMASK_SET);
  
  
      ngx_conf_merge_bitmask_value(conf->upstream.next_upstream,
                                prev->upstream.next_upstream,
                                (NGX_CONF_BITMASK_SET
                                 |NGX_HTTP_UPSTREAM_FT_ERROR
                                 |NGX_HTTP_UPSTREAM_FT_TIMEOUT));
  
      if (conf->upstream.next_upstream & NGX_HTTP_UPSTREAM_FT_OFF) {
          conf->upstream.next_upstream = NGX_CONF_BITMASK_SET
                                         |NGX_HTTP_UPSTREAM_FT_OFF;
      }
  
      if (ngx_conf_merge_path_value(cf, &conf->upstream.temp_path,
                                prev->upstream.temp_path,
                                &ngx_http_proxy_temp_path)
          != NGX_OK)
      {
          return NGX_CONF_ERROR;
      }
  
  
  #if (NGX_HTTP_CACHE)
  
      if (conf->upstream.cache == NGX_CONF_UNSET) {
          ngx_conf_merge_value(conf->upstream.cache,
                                prev->upstream.cache, 0);
  
          conf->upstream.cache_zone = prev->upstream.cache_zone;
          conf->upstream.cache_value = prev->upstream.cache_value;
      }
  
      if (conf->upstream.cache_zone && conf->upstream.cache_zone->data == NULL) {
          ngx_shm_zone_t  *shm_zone;
  
          shm_zone = conf->upstream.cache_zone;
  
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "\"proxy_cache\" zone \"%V\" is unknown",
                             &shm_zone->shm.name);
  
          return NGX_CONF_ERROR;
      }
  
      ngx_conf_merge_uint_value(conf->upstream.cache_min_uses,
                                prev->upstream.cache_min_uses, 1);
  
      ngx_conf_merge_off_value(conf->upstream.cache_max_range_offset,
                                prev->upstream.cache_max_range_offset,
                                NGX_MAX_OFF_T_VALUE);
  
      ngx_conf_merge_bitmask_value(conf->upstream.cache_use_stale,
                                prev->upstream.cache_use_stale,
                                (NGX_CONF_BITMASK_SET
                                 |NGX_HTTP_UPSTREAM_FT_OFF));
  
      if (conf->upstream.cache_use_stale & NGX_HTTP_UPSTREAM_FT_OFF) {
          conf->upstream.cache_use_stale = NGX_CONF_BITMASK_SET
                                           |NGX_HTTP_UPSTREAM_FT_OFF;
      }
  
      if (conf->upstream.cache_use_stale & NGX_HTTP_UPSTREAM_FT_ERROR) {
          conf->upstream.cache_use_stale |= NGX_HTTP_UPSTREAM_FT_NOLIVE;
      }
  
      if (conf->upstream.cache_methods == 0) {
          conf->upstream.cache_methods = prev->upstream.cache_methods;
      }
  
      conf->upstream.cache_methods |= NGX_HTTP_GET|NGX_HTTP_HEAD;
  
      ngx_conf_merge_ptr_value(conf->upstream.cache_bypass,
                               prev->upstream.cache_bypass, NULL);
  
      ngx_conf_merge_ptr_value(conf->upstream.no_cache,
                               prev->upstream.no_cache, NULL);
  
      ngx_conf_merge_ptr_value(conf->upstream.cache_valid,
                               prev->upstream.cache_valid, NULL);
  
      if (conf->cache_key.value.data == NULL) {
          conf->cache_key = prev->cache_key;
      }
  
      ngx_conf_merge_value(conf->upstream.cache_lock,
                                prev->upstream.cache_lock, 0);
  
      ngx_conf_merge_msec_value(conf->upstream.cache_lock_timeout,
                                prev->upstream.cache_lock_timeout, 5000);
  
      ngx_conf_merge_msec_value(conf->upstream.cache_lock_age,
                                prev->upstream.cache_lock_age, 5000);
  
      ngx_conf_merge_value(conf->upstream.cache_revalidate,
                                prev->upstream.cache_revalidate, 0);
  
      ngx_conf_merge_value(conf->upstream.cache_convert_head,
                                prev->upstream.cache_convert_head, 1);
  
      ngx_conf_merge_value(conf->upstream.cache_background_update,
                                prev->upstream.cache_background_update, 0);
  
  #endif
  
      if (conf->method == NULL) {
          conf->method = prev->method;
      }
  
      ngx_conf_merge_value(conf->upstream.pass_request_headers,
                                prev->upstream.pass_request_headers, 1);
      ngx_conf_merge_value(conf->upstream.pass_request_body,
                                prev->upstream.pass_request_body, 1);
  
      ngx_conf_merge_value(conf->upstream.intercept_errors,
                                prev->upstream.intercept_errors, 0);
  
  #if (NGX_HTTP_SSL)
  
      ngx_conf_merge_value(conf->upstream.ssl_session_reuse,
                                prev->upstream.ssl_session_reuse, 1);
  
      ngx_conf_merge_bitmask_value(conf->ssl_protocols, prev->ssl_protocols,
                                   (NGX_CONF_BITMASK_SET|NGX_SSL_TLSv1
                                    |NGX_SSL_TLSv1_1|NGX_SSL_TLSv1_2));
  
      ngx_conf_merge_str_value(conf->ssl_ciphers, prev->ssl_ciphers,
                               "DEFAULT");
  
      if (conf->upstream.ssl_name == NULL) {
          conf->upstream.ssl_name = prev->upstream.ssl_name;
      }
  
      ngx_conf_merge_value(conf->upstream.ssl_server_name,
                                prev->upstream.ssl_server_name, 0);
      ngx_conf_merge_value(conf->upstream.ssl_verify,
                                prev->upstream.ssl_verify, 0);
      ngx_conf_merge_uint_value(conf->ssl_verify_depth,
                                prev->ssl_verify_depth, 1);
      ngx_conf_merge_str_value(conf->ssl_trusted_certificate,
                                prev->ssl_trusted_certificate, "");
      ngx_conf_merge_str_value(conf->ssl_crl, prev->ssl_crl, "");
  
      ngx_conf_merge_str_value(conf->ssl_certificate,
                                prev->ssl_certificate, "");
      ngx_conf_merge_str_value(conf->ssl_certificate_key,
                                prev->ssl_certificate_key, "");
      ngx_conf_merge_ptr_value(conf->ssl_passwords, prev->ssl_passwords, NULL);
  
      if (conf->ssl && ngx_http_proxy_set_ssl(cf, conf) != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
  #endif
  
      ngx_conf_merge_value(conf->redirect, prev->redirect, 1);
  
      if (conf->redirect) {
  
          if (conf->redirects == NULL) {
              conf->redirects = prev->redirects;
          }
  
          if (conf->redirects == NULL && conf->url.data) {
  
              conf->redirects = ngx_array_create(cf->pool, 1,
                                               sizeof(ngx_http_proxy_rewrite_t));
              if (conf->redirects == NULL) {
                  return NGX_CONF_ERROR;
              }
  
              pr = ngx_array_push(conf->redirects);
              if (pr == NULL) {
                  return NGX_CONF_ERROR;
              }
  
              ngx_memzero(&pr->pattern.complex,
                          sizeof(ngx_http_complex_value_t));
  
              ngx_memzero(&pr->replacement, sizeof(ngx_http_complex_value_t));
  
              pr->handler = ngx_http_proxy_rewrite_complex_handler;
  
              if (conf->vars.uri.len) {
                  pr->pattern.complex.value = conf->url;
                  pr->replacement.value = conf->location;
  
              } else {
                  pr->pattern.complex.value.len = conf->url.len
                                                  + sizeof("/") - 1;
  
                  p = ngx_pnalloc(cf->pool, pr->pattern.complex.value.len);
                  if (p == NULL) {
                      return NGX_CONF_ERROR;
                  }
  
                  pr->pattern.complex.value.data = p;
  
                  p = ngx_cpymem(p, conf->url.data, conf->url.len);
                  *p = '/';
  
                  ngx_str_set(&pr->replacement.value, "/");
              }
          }
      }
  
      ngx_conf_merge_ptr_value(conf->cookie_domains, prev->cookie_domains, NULL);
  
      ngx_conf_merge_ptr_value(conf->cookie_paths, prev->cookie_paths, NULL);
  
      ngx_conf_merge_uint_value(conf->http_version, prev->http_version,
                                NGX_HTTP_VERSION_10);
  
      ngx_conf_merge_uint_value(conf->headers_hash_max_size,
                                prev->headers_hash_max_size, 512);
  
      ngx_conf_merge_uint_value(conf->headers_hash_bucket_size,
                                prev->headers_hash_bucket_size, 64);
  
      conf->headers_hash_bucket_size = ngx_align(conf->headers_hash_bucket_size,
                                                 ngx_cacheline_size);
  
      hash.max_size = conf->headers_hash_max_size;
      hash.bucket_size = conf->headers_hash_bucket_size;
      hash.name = "proxy_headers_hash";
  
      if (ngx_http_upstream_hide_headers_hash(cf, &conf->upstream,
              &prev->upstream, ngx_http_proxy_hide_headers, &hash)
          != NGX_OK)
      {
          return NGX_CONF_ERROR;
      }
  
      clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
  
      if (clcf->noname
          && conf->upstream.upstream == NULL && conf->proxy_lengths == NULL)
      {
          conf->upstream.upstream = prev->upstream.upstream;
          conf->location = prev->location;
          conf->vars = prev->vars;
  
          conf->proxy_lengths = prev->proxy_lengths;
          conf->proxy_values = prev->proxy_values;
  
  #if (NGX_HTTP_SSL)
          conf->upstream.ssl = prev->upstream.ssl;
  #endif
      }
  
      if (clcf->lmt_excpt && clcf->handler == NULL
          && (conf->upstream.upstream || conf->proxy_lengths))
      {
          clcf->handler = ngx_http_proxy_handler;
      }
  
      if (conf->body_source.data == NULL) {
          conf->body_flushes = prev->body_flushes;
          conf->body_source = prev->body_source;
          conf->body_lengths = prev->body_lengths;
          conf->body_values = prev->body_values;
      }
  
      if (conf->body_source.data && conf->body_lengths == NULL) {
  
          ngx_memzero(&sc, sizeof(ngx_http_script_compile_t));
  
          sc.cf = cf;
          sc.source = &conf->body_source;
          sc.flushes = &conf->body_flushes;
          sc.lengths = &conf->body_lengths;
          sc.values = &conf->body_values;
          sc.complete_lengths = 1;
          sc.complete_values = 1;
  
          if (ngx_http_script_compile(&sc) != NGX_OK) {
              return NGX_CONF_ERROR;
          }
      }
  
      if (conf->headers_source == NULL) {
          conf->headers = prev->headers;
  #if (NGX_HTTP_CACHE)
          conf->headers_cache = prev->headers_cache;
  #endif
          conf->headers_source = prev->headers_source;
      }
  
      rc = ngx_http_proxy_init_headers(cf, conf, &conf->headers,
                                       ngx_http_proxy_headers);
      if (rc != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
  #if (NGX_HTTP_CACHE)
  
      if (conf->upstream.cache) {
          rc = ngx_http_proxy_init_headers(cf, conf, &conf->headers_cache,
                                           ngx_http_proxy_cache_headers);
          if (rc != NGX_OK) {
              return NGX_CONF_ERROR;
          }
      }
  
  #endif
  
      /*
       * special handling to preserve conf->headers in the "http" section
       * to inherit it to all servers
       */
  
      if (prev->headers.hash.buckets == NULL
          && conf->headers_source == prev->headers_source)
      {
          prev->headers = conf->headers;
  #if (NGX_HTTP_CACHE)
          prev->headers_cache = conf->headers_cache;
  #endif
      }
  
      return NGX_CONF_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_init_headers(ngx_conf_t *cf, ngx_http_proxy_loc_conf_t *conf,
      ngx_http_proxy_headers_t *headers, ngx_keyval_t *default_headers)
  {
      u_char                       *p;
      size_t                        size;
      uintptr_t                    *code;
      ngx_uint_t                    i;
      ngx_array_t                   headers_names, headers_merged;
      ngx_keyval_t                 *src, *s, *h;
      ngx_hash_key_t               *hk;
      ngx_hash_init_t               hash;
      ngx_http_script_compile_t     sc;
      ngx_http_script_copy_code_t  *copy;
  
      if (headers->hash.buckets) {
          return NGX_OK;
      }
  
      if (ngx_array_init(&headers_names, cf->temp_pool, 4, sizeof(ngx_hash_key_t))
          != NGX_OK)
      {
          return NGX_ERROR;
      }
  
      if (ngx_array_init(&headers_merged, cf->temp_pool, 4, sizeof(ngx_keyval_t))
          != NGX_OK)
      {
          return NGX_ERROR;
      }
  
      headers->lengths = ngx_array_create(cf->pool, 64, 1);
      if (headers->lengths == NULL) {
          return NGX_ERROR;
      }
  
      headers->values = ngx_array_create(cf->pool, 512, 1);
      if (headers->values == NULL) {
          return NGX_ERROR;
      }
  
      if (conf->headers_source) {
  
          src = conf->headers_source->elts;
          for (i = 0; i < conf->headers_source->nelts; i++) {
  
              s = ngx_array_push(&headers_merged);
              if (s == NULL) {
                  return NGX_ERROR;
              }
  
              *s = src[i];
          }
      }
  
      h = default_headers;
  
      while (h->key.len) {
  
          src = headers_merged.elts;
          for (i = 0; i < headers_merged.nelts; i++) {
              if (ngx_strcasecmp(h->key.data, src[i].key.data) == 0) {
                  goto next;
              }
          }
  
          s = ngx_array_push(&headers_merged);
          if (s == NULL) {
              return NGX_ERROR;
          }
  
          *s = *h;
  
      next:
  
          h++;
      }
  
  
      src = headers_merged.elts;
      for (i = 0; i < headers_merged.nelts; i++) {
  
          hk = ngx_array_push(&headers_names);
          if (hk == NULL) {
              return NGX_ERROR;
          }
  
          hk->key = src[i].key;
          hk->key_hash = ngx_hash_key_lc(src[i].key.data, src[i].key.len);
          hk->value = (void *) 1;
  
          if (src[i].value.len == 0) {
              continue;
          }
  
          copy = ngx_array_push_n(headers->lengths,
                                  sizeof(ngx_http_script_copy_code_t));
          if (copy == NULL) {
              return NGX_ERROR;
          }
  
          copy->code = (ngx_http_script_code_pt) ngx_http_script_copy_len_code;
          copy->len = src[i].key.len;
  
          size = (sizeof(ngx_http_script_copy_code_t)
                  + src[i].key.len + sizeof(uintptr_t) - 1)
                 & ~(sizeof(uintptr_t) - 1);
  
          copy = ngx_array_push_n(headers->values, size);
          if (copy == NULL) {
              return NGX_ERROR;
          }
  
          copy->code = ngx_http_script_copy_code;
          copy->len = src[i].key.len;
  
          p = (u_char *) copy + sizeof(ngx_http_script_copy_code_t);
          ngx_memcpy(p, src[i].key.data, src[i].key.len);
  
          ngx_memzero(&sc, sizeof(ngx_http_script_compile_t));
  
          sc.cf = cf;
          sc.source = &src[i].value;
          sc.flushes = &headers->flushes;
          sc.lengths = &headers->lengths;
          sc.values = &headers->values;
  
          if (ngx_http_script_compile(&sc) != NGX_OK) {
              return NGX_ERROR;
          }
  
          code = ngx_array_push_n(headers->lengths, sizeof(uintptr_t));
          if (code == NULL) {
              return NGX_ERROR;
          }
  
          *code = (uintptr_t) NULL;
  
          code = ngx_array_push_n(headers->values, sizeof(uintptr_t));
          if (code == NULL) {
              return NGX_ERROR;
          }
  
          *code = (uintptr_t) NULL;
      }
  
      code = ngx_array_push_n(headers->lengths, sizeof(uintptr_t));
      if (code == NULL) {
          return NGX_ERROR;
      }
  
      *code = (uintptr_t) NULL;
  
  
      hash.hash = &headers->hash;
      hash.key = ngx_hash_key_lc;
      hash.max_size = conf->headers_hash_max_size;
      hash.bucket_size = conf->headers_hash_bucket_size;
      hash.name = "proxy_headers_hash";
      hash.pool = cf->pool;
      hash.temp_pool = NULL;
  
      return ngx_hash_init(&hash, headers_names.elts, headers_names.nelts);
  }
  
  
  static char *
  ngx_http_proxy_pass(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_proxy_loc_conf_t *plcf = conf;
  
      size_t                      add;
      u_short                     port;
      ngx_str_t                  *value, *url;
      ngx_url_t                   u;
      ngx_uint_t                  n;
      ngx_http_core_loc_conf_t   *clcf;
      ngx_http_script_compile_t   sc;
  
      if (plcf->upstream.upstream || plcf->proxy_lengths) {
          return "is duplicate";
      }
  
      clcf = ngx_http_conf_get_module_loc_conf(cf, ngx_http_core_module);
  
      clcf->handler = ngx_http_proxy_handler;
  
      if (clcf->name.data[clcf->name.len - 1] == '/') {
          clcf->auto_redirect = 1;
      }
  
      value = cf->args->elts;
  
      url = &value[1];
  
      n = ngx_http_script_variables_count(url);
  
      if (n) {
  
          ngx_memzero(&sc, sizeof(ngx_http_script_compile_t));
  
          sc.cf = cf;
          sc.source = url;
          sc.lengths = &plcf->proxy_lengths;
          sc.values = &plcf->proxy_values;
          sc.variables = n;
          sc.complete_lengths = 1;
          sc.complete_values = 1;
  
          if (ngx_http_script_compile(&sc) != NGX_OK) {
              return NGX_CONF_ERROR;
          }
  
  #if (NGX_HTTP_SSL)
          plcf->ssl = 1;
  #endif
  
          return NGX_CONF_OK;
      }
  
      if (ngx_strncasecmp(url->data, (u_char *) "http://", 7) == 0) {
          add = 7;
          port = 80;
  
      } else if (ngx_strncasecmp(url->data, (u_char *) "https://", 8) == 0) {
  
  #if (NGX_HTTP_SSL)
          plcf->ssl = 1;
  
          add = 8;
          port = 443;
  #else
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "https protocol requires SSL support");
          return NGX_CONF_ERROR;
  #endif
  
      } else {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid URL prefix");
          return NGX_CONF_ERROR;
      }
  
      ngx_memzero(&u, sizeof(ngx_url_t));
  
      u.url.len = url->len - add;
      u.url.data = url->data + add;
      u.default_port = port;
      u.uri_part = 1;
      u.no_resolve = 1;
  
      plcf->upstream.upstream = ngx_http_upstream_add(cf, &u, 0);
      if (plcf->upstream.upstream == NULL) {
          return NGX_CONF_ERROR;
      }
  
      plcf->vars.schema.len = add;
      plcf->vars.schema.data = url->data;
      plcf->vars.key_start = plcf->vars.schema;
  
      ngx_http_proxy_set_vars(&u, &plcf->vars);
  
      plcf->location = clcf->name;
  
      if (clcf->named
  #if (NGX_PCRE)
          || clcf->regex
  #endif
          || clcf->noname)
      {
          if (plcf->vars.uri.len) {
              ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                 "\"proxy_pass\" cannot have URI part in "
                                 "location given by regular expression, "
                                 "or inside named location, "
                                 "or inside \"if\" statement, "
                                 "or inside \"limit_except\" block");
              return NGX_CONF_ERROR;
          }
  
          plcf->location.len = 0;
      }
  
      plcf->url = *url;
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_proxy_redirect(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_proxy_loc_conf_t *plcf = conf;
  
      u_char                            *p;
      ngx_str_t                         *value;
      ngx_http_proxy_rewrite_t          *pr;
      ngx_http_compile_complex_value_t   ccv;
  
      if (plcf->redirect == 0) {
          return NGX_CONF_OK;
      }
  
      plcf->redirect = 1;
  
      value = cf->args->elts;
  
      if (cf->args->nelts == 2) {
          if (ngx_strcmp(value[1].data, "off") == 0) {
              plcf->redirect = 0;
              plcf->redirects = NULL;
              return NGX_CONF_OK;
          }
  
          if (ngx_strcmp(value[1].data, "false") == 0) {
              ngx_conf_log_error(NGX_LOG_ERR, cf, 0,
                             "invalid parameter \"false\", use \"off\" instead");
              plcf->redirect = 0;
              plcf->redirects = NULL;
              return NGX_CONF_OK;
          }
  
          if (ngx_strcmp(value[1].data, "default") != 0) {
              ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                 "invalid parameter \"%V\"", &value[1]);
              return NGX_CONF_ERROR;
          }
      }
  
      if (plcf->redirects == NULL) {
          plcf->redirects = ngx_array_create(cf->pool, 1,
                                             sizeof(ngx_http_proxy_rewrite_t));
          if (plcf->redirects == NULL) {
              return NGX_CONF_ERROR;
          }
      }
  
      pr = ngx_array_push(plcf->redirects);
      if (pr == NULL) {
          return NGX_CONF_ERROR;
      }
  
      if (ngx_strcmp(value[1].data, "default") == 0) {
          if (plcf->proxy_lengths) {
              ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                 "\"proxy_redirect default\" cannot be used "
                                 "with \"proxy_pass\" directive with variables");
              return NGX_CONF_ERROR;
          }
  
          if (plcf->url.data == NULL) {
              ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                 "\"proxy_redirect default\" should be placed "
                                 "after the \"proxy_pass\" directive");
              return NGX_CONF_ERROR;
          }
  
          pr->handler = ngx_http_proxy_rewrite_complex_handler;
  
          ngx_memzero(&pr->pattern.complex, sizeof(ngx_http_complex_value_t));
  
          ngx_memzero(&pr->replacement, sizeof(ngx_http_complex_value_t));
  
          if (plcf->vars.uri.len) {
              pr->pattern.complex.value = plcf->url;
              pr->replacement.value = plcf->location;
  
          } else {
              pr->pattern.complex.value.len = plcf->url.len + sizeof("/") - 1;
  
              p = ngx_pnalloc(cf->pool, pr->pattern.complex.value.len);
              if (p == NULL) {
                  return NGX_CONF_ERROR;
              }
  
              pr->pattern.complex.value.data = p;
  
              p = ngx_cpymem(p, plcf->url.data, plcf->url.len);
              *p = '/';
  
              ngx_str_set(&pr->replacement.value, "/");
          }
  
          return NGX_CONF_OK;
      }
  
  
      if (value[1].data[0] == '~') {
          value[1].len--;
          value[1].data++;
  
          if (value[1].data[0] == '*') {
              value[1].len--;
              value[1].data++;
  
              if (ngx_http_proxy_rewrite_regex(cf, pr, &value[1], 1) != NGX_OK) {
                  return NGX_CONF_ERROR;
              }
  
          } else {
              if (ngx_http_proxy_rewrite_regex(cf, pr, &value[1], 0) != NGX_OK) {
                  return NGX_CONF_ERROR;
              }
          }
  
      } else {
  
          ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));
  
          ccv.cf = cf;
          ccv.value = &value[1];
          ccv.complex_value = &pr->pattern.complex;
  
          if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
              return NGX_CONF_ERROR;
          }
  
          pr->handler = ngx_http_proxy_rewrite_complex_handler;
      }
  
  
      ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));
  
      ccv.cf = cf;
      ccv.value = &value[2];
      ccv.complex_value = &pr->replacement;
  
      if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_proxy_cookie_domain(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_proxy_loc_conf_t *plcf = conf;
  
      ngx_str_t                         *value;
      ngx_http_proxy_rewrite_t          *pr;
      ngx_http_compile_complex_value_t   ccv;
  
      if (plcf->cookie_domains == NULL) {
          return NGX_CONF_OK;
      }
  
      value = cf->args->elts;
  
      if (cf->args->nelts == 2) {
  
          if (ngx_strcmp(value[1].data, "off") == 0) {
              plcf->cookie_domains = NULL;
              return NGX_CONF_OK;
          }
  
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "invalid parameter \"%V\"", &value[1]);
          return NGX_CONF_ERROR;
      }
  
      if (plcf->cookie_domains == NGX_CONF_UNSET_PTR) {
          plcf->cookie_domains = ngx_array_create(cf->pool, 1,
                                       sizeof(ngx_http_proxy_rewrite_t));
          if (plcf->cookie_domains == NULL) {
              return NGX_CONF_ERROR;
          }
      }
  
      pr = ngx_array_push(plcf->cookie_domains);
      if (pr == NULL) {
          return NGX_CONF_ERROR;
      }
  
      if (value[1].data[0] == '~') {
          value[1].len--;
          value[1].data++;
  
          if (ngx_http_proxy_rewrite_regex(cf, pr, &value[1], 1) != NGX_OK) {
              return NGX_CONF_ERROR;
          }
  
      } else {
  
          if (value[1].data[0] == '.') {
              value[1].len--;
              value[1].data++;
          }
  
          ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));
  
          ccv.cf = cf;
          ccv.value = &value[1];
          ccv.complex_value = &pr->pattern.complex;
  
          if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
              return NGX_CONF_ERROR;
          }
  
          pr->handler = ngx_http_proxy_rewrite_domain_handler;
  
          if (value[2].data[0] == '.') {
              value[2].len--;
              value[2].data++;
          }
      }
  
      ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));
  
      ccv.cf = cf;
      ccv.value = &value[2];
      ccv.complex_value = &pr->replacement;
  
      if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_proxy_cookie_path(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_proxy_loc_conf_t *plcf = conf;
  
      ngx_str_t                         *value;
      ngx_http_proxy_rewrite_t          *pr;
      ngx_http_compile_complex_value_t   ccv;
  
      if (plcf->cookie_paths == NULL) {
          return NGX_CONF_OK;
      }
  
      value = cf->args->elts;
  
      if (cf->args->nelts == 2) {
  
          if (ngx_strcmp(value[1].data, "off") == 0) {
              plcf->cookie_paths = NULL;
              return NGX_CONF_OK;
          }
  
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "invalid parameter \"%V\"", &value[1]);
          return NGX_CONF_ERROR;
      }
  
      if (plcf->cookie_paths == NGX_CONF_UNSET_PTR) {
          plcf->cookie_paths = ngx_array_create(cf->pool, 1,
                                       sizeof(ngx_http_proxy_rewrite_t));
          if (plcf->cookie_paths == NULL) {
              return NGX_CONF_ERROR;
          }
      }
  
      pr = ngx_array_push(plcf->cookie_paths);
      if (pr == NULL) {
          return NGX_CONF_ERROR;
      }
  
      if (value[1].data[0] == '~') {
          value[1].len--;
          value[1].data++;
  
          if (value[1].data[0] == '*') {
              value[1].len--;
              value[1].data++;
  
              if (ngx_http_proxy_rewrite_regex(cf, pr, &value[1], 1) != NGX_OK) {
                  return NGX_CONF_ERROR;
              }
  
          } else {
              if (ngx_http_proxy_rewrite_regex(cf, pr, &value[1], 0) != NGX_OK) {
                  return NGX_CONF_ERROR;
              }
          }
  
      } else {
  
          ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));
  
          ccv.cf = cf;
          ccv.value = &value[1];
          ccv.complex_value = &pr->pattern.complex;
  
          if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
              return NGX_CONF_ERROR;
          }
  
          pr->handler = ngx_http_proxy_rewrite_complex_handler;
      }
  
      ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));
  
      ccv.cf = cf;
      ccv.value = &value[2];
      ccv.complex_value = &pr->replacement;
  
      if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
      return NGX_CONF_OK;
  }
  
  
  static ngx_int_t
  ngx_http_proxy_rewrite_regex(ngx_conf_t *cf, ngx_http_proxy_rewrite_t *pr,
      ngx_str_t *regex, ngx_uint_t caseless)
  {
  #if (NGX_PCRE)
      u_char               errstr[NGX_MAX_CONF_ERRSTR];
      ngx_regex_compile_t  rc;
  
      ngx_memzero(&rc, sizeof(ngx_regex_compile_t));
  
      rc.pattern = *regex;
      rc.err.len = NGX_MAX_CONF_ERRSTR;
      rc.err.data = errstr;
  
      if (caseless) {
          rc.options = NGX_REGEX_CASELESS;
      }
  
      pr->pattern.regex = ngx_http_regex_compile(cf, &rc);
      if (pr->pattern.regex == NULL) {
          return NGX_ERROR;
      }
  
      pr->handler = ngx_http_proxy_rewrite_regex_handler;
  
      return NGX_OK;
  
  #else
  
      ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                         "using regex \"%V\" requires PCRE library", regex);
      return NGX_ERROR;
  
  #endif
  }
  
  
  static char *
  ngx_http_proxy_store(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_proxy_loc_conf_t *plcf = conf;
  
      ngx_str_t                  *value;
      ngx_http_script_compile_t   sc;
  
      if (plcf->upstream.store != NGX_CONF_UNSET) {
          return "is duplicate";
      }
  
      value = cf->args->elts;
  
      if (ngx_strcmp(value[1].data, "off") == 0) {
          plcf->upstream.store = 0;
          return NGX_CONF_OK;
      }
  
  #if (NGX_HTTP_CACHE)
      if (plcf->upstream.cache > 0) {
          return "is incompatible with \"proxy_cache\"";
      }
  #endif
  
      plcf->upstream.store = 1;
  
      if (ngx_strcmp(value[1].data, "on") == 0) {
          return NGX_CONF_OK;
      }
  
      /* include the terminating '\0' into script */
      value[1].len++;
  
      ngx_memzero(&sc, sizeof(ngx_http_script_compile_t));
  
      sc.cf = cf;
      sc.source = &value[1];
      sc.lengths = &plcf->upstream.store_lengths;
      sc.values = &plcf->upstream.store_values;
      sc.variables = ngx_http_script_variables_count(&value[1]);
      sc.complete_lengths = 1;
      sc.complete_values = 1;
  
      if (ngx_http_script_compile(&sc) != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
      return NGX_CONF_OK;
  }
  
  
  #if (NGX_HTTP_CACHE)
  
  static char *
  ngx_http_proxy_cache(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_proxy_loc_conf_t *plcf = conf;
  
      ngx_str_t                         *value;
      ngx_http_complex_value_t           cv;
      ngx_http_compile_complex_value_t   ccv;
  
      value = cf->args->elts;
  
      if (plcf->upstream.cache != NGX_CONF_UNSET) {
          return "is duplicate";
      }
  
      if (ngx_strcmp(value[1].data, "off") == 0) {
          plcf->upstream.cache = 0;
          return NGX_CONF_OK;
      }
  
      if (plcf->upstream.store > 0) {
          return "is incompatible with \"proxy_store\"";
      }
  
      plcf->upstream.cache = 1;
  
      ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));
  
      ccv.cf = cf;
      ccv.value = &value[1];
      ccv.complex_value = &cv;
  
      if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
      if (cv.lengths != NULL) {
  
          plcf->upstream.cache_value = ngx_palloc(cf->pool,
                                               sizeof(ngx_http_complex_value_t));
          if (plcf->upstream.cache_value == NULL) {
              return NGX_CONF_ERROR;
          }
  
          *plcf->upstream.cache_value = cv;
  
          return NGX_CONF_OK;
      }
  
      plcf->upstream.cache_zone = ngx_shared_memory_add(cf, &value[1], 0,
                                                        &ngx_http_proxy_module);
      if (plcf->upstream.cache_zone == NULL) {
          return NGX_CONF_ERROR;
      }
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_proxy_cache_key(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_proxy_loc_conf_t *plcf = conf;
  
      ngx_str_t                         *value;
      ngx_http_compile_complex_value_t   ccv;
  
      value = cf->args->elts;
  
      if (plcf->cache_key.value.data) {
          return "is duplicate";
      }
  
      ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));
  
      ccv.cf = cf;
      ccv.value = &value[1];
      ccv.complex_value = &plcf->cache_key;
  
      if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
      return NGX_CONF_OK;
  }
  
  #endif
  
  
  #if (NGX_HTTP_SSL)
  
  static char *
  ngx_http_proxy_ssl_password_file(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_proxy_loc_conf_t *plcf = conf;
  
      ngx_str_t  *value;
  
      if (plcf->ssl_passwords != NGX_CONF_UNSET_PTR) {
          return "is duplicate";
      }
  
      value = cf->args->elts;
  
      plcf->ssl_passwords = ngx_ssl_read_password_file(cf, &value[1]);
  
      if (plcf->ssl_passwords == NULL) {
          return NGX_CONF_ERROR;
      }
  
      return NGX_CONF_OK;
  }
  
  #endif
  
  
  static char *
  ngx_http_proxy_lowat_check(ngx_conf_t *cf, void *post, void *data)
  {
  #if (NGX_FREEBSD)
      ssize_t *np = data;
  
      if ((u_long) *np >= ngx_freebsd_net_inet_tcp_sendspace) {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "\"proxy_send_lowat\" must be less than %d "
                             "(sysctl net.inet.tcp.sendspace)",
                             ngx_freebsd_net_inet_tcp_sendspace);
  
          return NGX_CONF_ERROR;
      }
  
  #elif !(NGX_HAVE_SO_SNDLOWAT)
      ssize_t *np = data;
  
      ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
                         "\"proxy_send_lowat\" is not supported, ignored");
  
      *np = 0;
  
  #endif
  
      return NGX_CONF_OK;
  }
  
  
  #if (NGX_HTTP_SSL)
  
  static ngx_int_t
  ngx_http_proxy_set_ssl(ngx_conf_t *cf, ngx_http_proxy_loc_conf_t *plcf)
  {
      ngx_pool_cleanup_t  *cln;
  
      plcf->upstream.ssl = ngx_pcalloc(cf->pool, sizeof(ngx_ssl_t));
      if (plcf->upstream.ssl == NULL) {
          return NGX_ERROR;
      }
  
      plcf->upstream.ssl->log = cf->log;
  
      if (ngx_ssl_create(plcf->upstream.ssl, plcf->ssl_protocols, NULL)
          != NGX_OK)
      {
          return NGX_ERROR;
      }
  
      cln = ngx_pool_cleanup_add(cf->pool, 0);
      if (cln == NULL) {
          return NGX_ERROR;
      }
  
      cln->handler = ngx_ssl_cleanup_ctx;
      cln->data = plcf->upstream.ssl;
  
      if (plcf->ssl_certificate.len) {
  
          if (plcf->ssl_certificate_key.len == 0) {
              ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                            "no \"proxy_ssl_certificate_key\" is defined "
                            "for certificate \"%V\"", &plcf->ssl_certificate);
              return NGX_ERROR;
          }
  
          if (ngx_ssl_certificate(cf, plcf->upstream.ssl, &plcf->ssl_certificate,
                                  &plcf->ssl_certificate_key, plcf->ssl_passwords)
              != NGX_OK)
          {
              return NGX_ERROR;
          }
      }
  
      if (ngx_ssl_ciphers(cf, plcf->upstream.ssl, &plcf->ssl_ciphers, 0)
          != NGX_OK)
      {
          return NGX_ERROR;
      }
  
      if (plcf->upstream.ssl_verify) {
          if (plcf->ssl_trusted_certificate.len == 0) {
              ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                        "no proxy_ssl_trusted_certificate for proxy_ssl_verify");
              return NGX_ERROR;
          }
  
          if (ngx_ssl_trusted_certificate(cf, plcf->upstream.ssl,
                                          &plcf->ssl_trusted_certificate,
                                          plcf->ssl_verify_depth)
              != NGX_OK)
          {
              return NGX_ERROR;
          }
  
          if (ngx_ssl_crl(cf, plcf->upstream.ssl, &plcf->ssl_crl) != NGX_OK) {
              return NGX_ERROR;
          }
      }
  
      return NGX_OK;
  }
  
  #endif
  
  
  static void
  ngx_http_proxy_set_vars(ngx_url_t *u, ngx_http_proxy_vars_t *v)
  {
      if (u->family != AF_UNIX) {
  
          if (u->no_port || u->port == u->default_port) {
  
              v->host_header = u->host;
  
              if (u->default_port == 80) {
                  ngx_str_set(&v->port, "80");
  
              } else {
                  ngx_str_set(&v->port, "443");
              }
  
          } else {
              v->host_header.len = u->host.len + 1 + u->port_text.len;
              v->host_header.data = u->host.data;
              v->port = u->port_text;
          }
  
          v->key_start.len += v->host_header.len;
  
      } else {
          ngx_str_set(&v->host_header, "localhost");
          ngx_str_null(&v->port);
          v->key_start.len += sizeof("unix:") - 1 + u->host.len + 1;
      }
  
      v->uri = u->uri;
  }
  