text: 
  /*
   * Copyright (C) Igor Sysoev
   * Copyright (C) Nginx, Inc.
   */
  
  
  #include <ngx_config.h>
  #include <ngx_core.h>
  #include <ngx_event.h>
  #include <ngx_mail.h>
  #include <ngx_mail_smtp_module.h>
  
  
  static void *ngx_mail_smtp_create_srv_conf(ngx_conf_t *cf);
  static char *ngx_mail_smtp_merge_srv_conf(ngx_conf_t *cf, void *parent,
      void *child);
  
  
  static ngx_conf_bitmask_t  ngx_mail_smtp_auth_methods[] = {
      { ngx_string("plain"), NGX_MAIL_AUTH_PLAIN_ENABLED },
      { ngx_string("login"), NGX_MAIL_AUTH_LOGIN_ENABLED },
      { ngx_string("cram-md5"), NGX_MAIL_AUTH_CRAM_MD5_ENABLED },
      { ngx_string("none"), NGX_MAIL_AUTH_NONE_ENABLED },
      { ngx_null_string, 0 }
  };
  
  
  static ngx_str_t  ngx_mail_smtp_auth_methods_names[] = {
      ngx_string("PLAIN"),
      ngx_string("LOGIN"),
      ngx_null_string,  /* APOP */
      ngx_string("CRAM-MD5"),
      ngx_null_string   /* NONE */
  };
  
  
  static ngx_mail_protocol_t  ngx_mail_smtp_protocol = {
      ngx_string("smtp"),
      { 25, 465, 587, 0 },
      NGX_MAIL_SMTP_PROTOCOL,
  
      ngx_mail_smtp_init_session,
      ngx_mail_smtp_init_protocol,
      ngx_mail_smtp_parse_command,
      ngx_mail_smtp_auth_state,
  
      ngx_string("451 4.3.2 Internal server error" CRLF)
  };
  
  
  static ngx_command_t  ngx_mail_smtp_commands[] = {
  
      { ngx_string("smtp_client_buffer"),
        NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_MAIL_SRV_CONF_OFFSET,
        offsetof(ngx_mail_smtp_srv_conf_t, client_buffer_size),
        NULL },
  
      { ngx_string("smtp_greeting_delay"),
        NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_msec_slot,
        NGX_MAIL_SRV_CONF_OFFSET,
        offsetof(ngx_mail_smtp_srv_conf_t, greeting_delay),
        NULL },
  
      { ngx_string("smtp_capabilities"),
        NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE,
        ngx_mail_capabilities,
        NGX_MAIL_SRV_CONF_OFFSET,
        offsetof(ngx_mail_smtp_srv_conf_t, capabilities),
        NULL },
  
      { ngx_string("smtp_auth"),
        NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE,
        ngx_conf_set_bitmask_slot,
        NGX_MAIL_SRV_CONF_OFFSET,
        offsetof(ngx_mail_smtp_srv_conf_t, auth_methods),
        &ngx_mail_smtp_auth_methods },
  
        ngx_null_command
  };
  
  
  static ngx_mail_module_t  ngx_mail_smtp_module_ctx = {
      &ngx_mail_smtp_protocol,               /* protocol */
  
      NULL,                                  /* create main configuration */
      NULL,                                  /* init main configuration */
  
      ngx_mail_smtp_create_srv_conf,         /* create server configuration */
      ngx_mail_smtp_merge_srv_conf           /* merge server configuration */
  };
  
  
  ngx_module_t  ngx_mail_smtp_module = {
      NGX_MODULE_V1,
      &ngx_mail_smtp_module_ctx,             /* module context */
      ngx_mail_smtp_commands,                /* module directives */
      NGX_MAIL_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 void *
  ngx_mail_smtp_create_srv_conf(ngx_conf_t *cf)
  {
      ngx_mail_smtp_srv_conf_t  *sscf;
  
      sscf = ngx_pcalloc(cf->pool, sizeof(ngx_mail_smtp_srv_conf_t));
      if (sscf == NULL) {
          return NULL;
      }
  
      sscf->client_buffer_size = NGX_CONF_UNSET_SIZE;
      sscf->greeting_delay = NGX_CONF_UNSET_MSEC;
  
      if (ngx_array_init(&sscf->capabilities, cf->pool, 4, sizeof(ngx_str_t))
          != NGX_OK)
      {
          return NULL;
      }
  
      return sscf;
  }
  
  
  static char *
  ngx_mail_smtp_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child)
  {
      ngx_mail_smtp_srv_conf_t *prev = parent;
      ngx_mail_smtp_srv_conf_t *conf = child;
  
      u_char                    *p, *auth, *last;
      size_t                     size;
      ngx_str_t                 *c;
      ngx_uint_t                 i, m, auth_enabled;
      ngx_mail_core_srv_conf_t  *cscf;
  
      ngx_conf_merge_size_value(conf->client_buffer_size,
                                prev->client_buffer_size,
                                (size_t) ngx_pagesize);
  
      ngx_conf_merge_msec_value(conf->greeting_delay,
                                prev->greeting_delay, 0);
  
      ngx_conf_merge_bitmask_value(conf->auth_methods,
                                prev->auth_methods,
                                (NGX_CONF_BITMASK_SET
                                 |NGX_MAIL_AUTH_PLAIN_ENABLED
                                 |NGX_MAIL_AUTH_LOGIN_ENABLED));
  
  
      cscf = ngx_mail_conf_get_module_srv_conf(cf, ngx_mail_core_module);
  
      size = sizeof("220  ESMTP ready" CRLF) - 1 + cscf->server_name.len;
  
      p = ngx_pnalloc(cf->pool, size);
      if (p == NULL) {
          return NGX_CONF_ERROR;
      }
  
      conf->greeting.len = size;
      conf->greeting.data = p;
  
      *p++ = '2'; *p++ = '2'; *p++ = '0'; *p++ = ' ';
      p = ngx_cpymem(p, cscf->server_name.data, cscf->server_name.len);
      ngx_memcpy(p, " ESMTP ready" CRLF, sizeof(" ESMTP ready" CRLF) - 1);
  
  
      size = sizeof("250 " CRLF) - 1 + cscf->server_name.len;
  
      p = ngx_pnalloc(cf->pool, size);
      if (p == NULL) {
          return NGX_CONF_ERROR;
      }
  
      conf->server_name.len = size;
      conf->server_name.data = p;
  
      *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = ' ';
      p = ngx_cpymem(p, cscf->server_name.data, cscf->server_name.len);
      *p++ = CR; *p = LF;
  
  
      if (conf->capabilities.nelts == 0) {
          conf->capabilities = prev->capabilities;
      }
  
      size = sizeof("250-") - 1 + cscf->server_name.len + sizeof(CRLF) - 1;
  
      c = conf->capabilities.elts;
      for (i = 0; i < conf->capabilities.nelts; i++) {
          size += sizeof("250 ") - 1 + c[i].len + sizeof(CRLF) - 1;
      }
  
      auth_enabled = 0;
  
      for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0;
           m <= NGX_MAIL_AUTH_CRAM_MD5_ENABLED;
           m <<= 1, i++)
      {
          if (m & conf->auth_methods) {
              size += 1 + ngx_mail_smtp_auth_methods_names[i].len;
              auth_enabled = 1;
          }
      }
  
      if (auth_enabled) {
          size += sizeof("250 AUTH") - 1 + sizeof(CRLF) - 1;
      }
  
      p = ngx_pnalloc(cf->pool, size);
      if (p == NULL) {
          return NGX_CONF_ERROR;
      }
  
      conf->capability.len = size;
      conf->capability.data = p;
  
      last = p;
  
      *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = '-';
      p = ngx_cpymem(p, cscf->server_name.data, cscf->server_name.len);
      *p++ = CR; *p++ = LF;
  
      for (i = 0; i < conf->capabilities.nelts; i++) {
          last = p;
          *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = '-';
          p = ngx_cpymem(p, c[i].data, c[i].len);
          *p++ = CR; *p++ = LF;
      }
  
      auth = p;
  
      if (auth_enabled) {
          last = p;
  
          *p++ = '2'; *p++ = '5'; *p++ = '0'; *p++ = ' ';
          *p++ = 'A'; *p++ = 'U'; *p++ = 'T'; *p++ = 'H';
  
          for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0;
               m <= NGX_MAIL_AUTH_CRAM_MD5_ENABLED;
               m <<= 1, i++)
          {
              if (m & conf->auth_methods) {
                  *p++ = ' ';
                  p = ngx_cpymem(p, ngx_mail_smtp_auth_methods_names[i].data,
                                 ngx_mail_smtp_auth_methods_names[i].len);
              }
          }
  
          *p++ = CR; *p = LF;
  
      } else {
          last[3] = ' ';
      }
  
      size += sizeof("250 STARTTLS" CRLF) - 1;
  
      p = ngx_pnalloc(cf->pool, size);
      if (p == NULL) {
          return NGX_CONF_ERROR;
      }
  
      conf->starttls_capability.len = size;
      conf->starttls_capability.data = p;
  
      p = ngx_cpymem(p, conf->capability.data, conf->capability.len);
  
      p = ngx_cpymem(p, "250 STARTTLS" CRLF, sizeof("250 STARTTLS" CRLF) - 1);
      *p++ = CR; *p = LF;
  
      p = conf->starttls_capability.data
          + (last - conf->capability.data) + 3;
      *p = '-';
  
      size = (auth - conf->capability.data)
              + sizeof("250 STARTTLS" CRLF) - 1;
  
      p = ngx_pnalloc(cf->pool, size);
      if (p == NULL) {
          return NGX_CONF_ERROR;
      }
  
      conf->starttls_only_capability.len = size;
      conf->starttls_only_capability.data = p;
  
      p = ngx_cpymem(p, conf->capability.data, auth - conf->capability.data);
  
      ngx_memcpy(p, "250 STARTTLS" CRLF, sizeof("250 STARTTLS" CRLF) - 1);
  
      if (last < auth) {
          p = conf->starttls_only_capability.data
              + (last - conf->capability.data) + 3;
          *p = '-';
      }
  
      return NGX_CONF_OK;
  }
  