text: /*
   * This file is part of the MicroPython project, http://micropython.org/
   *
   * The MIT License (MIT)
   *
   * Copyright (c) 2016 Linaro Ltd.
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  
  #include "py/mpconfig.h"
  #if MICROPY_PY_USSL && MICROPY_SSL_MBEDTLS
  
  #include <stdio.h>
  #include <string.h>
  #include <errno.h>
  
  #include "py/nlr.h"
  #include "py/runtime.h"
  #include "py/stream.h"
  
  // mbedtls_time_t
  #include "mbedtls/platform.h"
  #include "mbedtls/net.h"
  #include "mbedtls/ssl.h"
  #include "mbedtls/x509_crt.h"
  #include "mbedtls/pk.h"
  #include "mbedtls/entropy.h"
  #include "mbedtls/ctr_drbg.h"
  #include "mbedtls/debug.h"
  
  typedef struct _mp_obj_ssl_socket_t {
      mp_obj_base_t base;
      mp_obj_t sock;
      mbedtls_entropy_context entropy;
      mbedtls_ctr_drbg_context ctr_drbg;
      mbedtls_ssl_context ssl;
      mbedtls_ssl_config conf;
      mbedtls_x509_crt cacert;
      mbedtls_x509_crt cert;
      mbedtls_pk_context pkey;
  } mp_obj_ssl_socket_t;
  
  struct ssl_args {
      mp_arg_val_t key;
      mp_arg_val_t cert;
      mp_arg_val_t server_side;
      mp_arg_val_t server_hostname;
  };
  
  STATIC const mp_obj_type_t ussl_socket_type;
  
  static void mbedtls_debug(void *ctx, int level, const char *file, int line, const char *str) {
      printf("DBG:%s:%04d: %s\n", file, line, str);
  }
  
  // TODO: FIXME!
  int null_entropy_func(void *data, unsigned char *output, size_t len) {
      // enjoy random bytes
      return 0;
  }
  
  int _mbedtls_ssl_send(void *ctx, const byte *buf, size_t len) {
      mp_obj_t sock = *(mp_obj_t*)ctx;
  
      const mp_stream_p_t *sock_stream = mp_get_stream_raise(sock, MP_STREAM_OP_WRITE);
      int err;
  
      int out_sz = sock_stream->write(sock, buf, len, &err);
      if (out_sz == MP_STREAM_ERROR) {
          return -err;
      } else {
          return out_sz;
      }
  }
  
  int _mbedtls_ssl_recv(void *ctx, byte *buf, size_t len) {
      mp_obj_t sock = *(mp_obj_t*)ctx;
  
      const mp_stream_p_t *sock_stream = mp_get_stream_raise(sock, MP_STREAM_OP_READ);
      int err;
  
      int out_sz = sock_stream->read(sock, buf, len, &err);
      if (out_sz == MP_STREAM_ERROR) {
          return -err;
      } else {
          return out_sz;
      }
  }
  
  
  STATIC mp_obj_ssl_socket_t *socket_new(mp_obj_t sock, struct ssl_args *args) {
      mp_obj_ssl_socket_t *o = m_new_obj(mp_obj_ssl_socket_t);
      o->base.type = &ussl_socket_type;
  
      int ret;
      mbedtls_ssl_init(&o->ssl);
      mbedtls_ssl_config_init(&o->conf);
      mbedtls_x509_crt_init(&o->cacert);
      mbedtls_x509_crt_init(&o->cert);
      mbedtls_pk_init(&o->pkey);
      mbedtls_ctr_drbg_init(&o->ctr_drbg);
      // Debug level (0-4)
      mbedtls_debug_set_threshold(0);
  
      mbedtls_entropy_init(&o->entropy);
      const byte seed[] = "upy";
      ret = mbedtls_ctr_drbg_seed(&o->ctr_drbg, null_entropy_func/*mbedtls_entropy_func*/, &o->entropy, seed, sizeof(seed));
      if (ret != 0) {
          printf("ret=%d\n", ret);
          assert(0);
      }
  
      ret = mbedtls_ssl_config_defaults(&o->conf,
                      MBEDTLS_SSL_IS_CLIENT,
                      MBEDTLS_SSL_TRANSPORT_STREAM,
                      MBEDTLS_SSL_PRESET_DEFAULT);
      if (ret != 0) {
          assert(0);
      }
  
      mbedtls_ssl_conf_authmode(&o->conf, MBEDTLS_SSL_VERIFY_NONE);
      mbedtls_ssl_conf_rng(&o->conf, mbedtls_ctr_drbg_random, &o->ctr_drbg);
      mbedtls_ssl_conf_dbg(&o->conf, mbedtls_debug, NULL);
  
      ret = mbedtls_ssl_setup(&o->ssl, &o->conf);
      if (ret != 0) {
          assert(0);
      }
  
      if (args->server_hostname.u_obj != mp_const_none) {
          const char *sni = mp_obj_str_get_str(args->server_hostname.u_obj);
          ret = mbedtls_ssl_set_hostname(&o->ssl, sni);
          if (ret != 0) {
              assert(0);
          }
      }
  
      o->sock = sock;
      mbedtls_ssl_set_bio(&o->ssl, &o->sock, _mbedtls_ssl_send, _mbedtls_ssl_recv, NULL);
  
      if (args->key.u_obj != MP_OBJ_NULL) {
          size_t key_len;
          const byte *key = (const byte*)mp_obj_str_get_data(args->key.u_obj, &key_len);
          // len should include terminating null
          ret = mbedtls_pk_parse_key(&o->pkey, key, key_len + 1, NULL, 0);
          assert(ret == 0);
  
          size_t cert_len;
          const byte *cert = (const byte*)mp_obj_str_get_data(args->cert.u_obj, &cert_len);
          // len should include terminating null
          ret = mbedtls_x509_crt_parse(&o->cert, cert, cert_len + 1);
          assert(ret == 0);
  
          ret = mbedtls_ssl_conf_own_cert(&o->conf, &o->cert, &o->pkey);
          assert(ret == 0);
      }
  
      if (args->server_side.u_bool) {
          assert(0);
      } else {
          while ((ret = mbedtls_ssl_handshake(&o->ssl)) != 0) {
              if (ret != MBEDTLS_ERR_SSL_WANT_READ && ret != MBEDTLS_ERR_SSL_WANT_WRITE) {
                  //assert(0);
                  printf("mbedtls_ssl_handshake error: -%x\n", -ret);
                  mp_raise_OSError(MP_EIO);
              }
          }
      }
  
      return o;
  }
  
  STATIC void socket_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
      (void)kind;
      mp_obj_ssl_socket_t *self = MP_OBJ_TO_PTR(self_in);
      mp_printf(print, "<_SSLSocket %p>", self);
  }
  
  STATIC mp_uint_t socket_read(mp_obj_t o_in, void *buf, mp_uint_t size, int *errcode) {
      mp_obj_ssl_socket_t *o = MP_OBJ_TO_PTR(o_in);
  
      int ret = mbedtls_ssl_read(&o->ssl, buf, size);
      if (ret >= 0) {
          return ret;
      }
      *errcode = ret;
      return MP_STREAM_ERROR;
  }
  
  STATIC mp_uint_t socket_write(mp_obj_t o_in, const void *buf, mp_uint_t size, int *errcode) {
      mp_obj_ssl_socket_t *o = MP_OBJ_TO_PTR(o_in);
  
      int ret = mbedtls_ssl_write(&o->ssl, buf, size);
      if (ret >= 0) {
          return ret;
      }
      *errcode = ret;
      return MP_STREAM_ERROR;
  }
  
  STATIC mp_obj_t socket_setblocking(mp_obj_t self_in, mp_obj_t flag_in) {
      // Currently supports only blocking mode
      (void)self_in;
      if (!mp_obj_is_true(flag_in)) {
          mp_raise_NotImplementedError("");
      }
      return mp_const_none;
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_2(socket_setblocking_obj, socket_setblocking);
  
  STATIC mp_obj_t socket_close(mp_obj_t self_in) {
      mp_obj_ssl_socket_t *self = MP_OBJ_TO_PTR(self_in);
  
      mbedtls_x509_crt_free(&self->cacert);
      mbedtls_ssl_free(&self->ssl);
      mbedtls_ssl_config_free(&self->conf);
      mbedtls_ctr_drbg_free(&self->ctr_drbg);
      mbedtls_entropy_free(&self->entropy);
  
      mp_obj_t dest[2];
      mp_load_method(self->sock, MP_QSTR_close, dest);
      return mp_call_method_n_kw(0, 0, dest);
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_1(socket_close_obj, socket_close);
  
  STATIC const mp_rom_map_elem_t ussl_socket_locals_dict_table[] = {
      { MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
      { MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
      { MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
      { MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_stream_write_obj) },
      { MP_ROM_QSTR(MP_QSTR_setblocking), MP_ROM_PTR(&socket_setblocking_obj) },
      { MP_ROM_QSTR(MP_QSTR_close), MP_ROM_PTR(&socket_close_obj) },
  };
  
  STATIC MP_DEFINE_CONST_DICT(ussl_socket_locals_dict, ussl_socket_locals_dict_table);
  
  STATIC const mp_stream_p_t ussl_socket_stream_p = {
      .read = socket_read,
      .write = socket_write,
  };
  
  STATIC const mp_obj_type_t ussl_socket_type = {
      { &mp_type_type },
      // Save on qstr's, reuse same as for module
      .name = MP_QSTR_ussl,
      .print = socket_print,
      .getiter = NULL,
      .iternext = NULL,
      .protocol = &ussl_socket_stream_p,
      .locals_dict = (void*)&ussl_socket_locals_dict,
  };
  
  STATIC mp_obj_t mod_ssl_wrap_socket(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
      // TODO: Implement more args
      static const mp_arg_t allowed_args[] = {
          { MP_QSTR_key, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
          { MP_QSTR_cert, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
          { MP_QSTR_server_side, MP_ARG_KW_ONLY | MP_ARG_BOOL, {.u_bool = false} },
          { MP_QSTR_server_hostname, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = mp_const_none} },
      };
  
      // TODO: Check that sock implements stream protocol
      mp_obj_t sock = pos_args[0];
  
      struct ssl_args args;
      mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args,
          MP_ARRAY_SIZE(allowed_args), allowed_args, (mp_arg_val_t*)&args);
  
      return MP_OBJ_FROM_PTR(socket_new(sock, &args));
  }
  STATIC MP_DEFINE_CONST_FUN_OBJ_KW(mod_ssl_wrap_socket_obj, 1, mod_ssl_wrap_socket);
  
  STATIC const mp_rom_map_elem_t mp_module_ssl_globals_table[] = {
      { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_ussl) },
      { MP_ROM_QSTR(MP_QSTR_wrap_socket), MP_ROM_PTR(&mod_ssl_wrap_socket_obj) },
  };
  
  STATIC MP_DEFINE_CONST_DICT(mp_module_ssl_globals, mp_module_ssl_globals_table);
  
  const mp_obj_module_t mp_module_ussl = {
      .base = { &mp_type_module },
      .globals = (mp_obj_dict_t*)&mp_module_ssl_globals,
  };
  
  #endif // MICROPY_PY_USSL
  