OVMS3-idf/components/esp-tls/esp_tls.c
2020-02-27 15:20:22 +05:30

498 lines
17 KiB
C

// Copyright 2019 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <http_parser.h>
#include "esp_tls.h"
#include "esp_tls_error_capture_internal.h"
#include <errno.h>
static const char *TAG = "esp-tls";
#ifdef CONFIG_ESP_TLS_USING_MBEDTLS
#include "esp_tls_mbedtls.h"
#elif CONFIG_ESP_TLS_USING_WOLFSSL
#include "esp_tls_wolfssl.h"
#endif
#ifdef ESP_PLATFORM
#include <esp_log.h>
#else
#define ESP_LOGD(TAG, ...) //printf(__VA_ARGS__);
#define ESP_LOGE(TAG, ...) printf(__VA_ARGS__);
#endif
#ifdef CONFIG_ESP_TLS_USING_MBEDTLS
#define _esp_create_ssl_handle esp_create_mbedtls_handle
#define _esp_tls_handshake esp_mbedtls_handshake
#define _esp_tls_read esp_mbedtls_read
#define _esp_tls_write esp_mbedtls_write
#define _esp_tls_conn_delete esp_mbedtls_conn_delete
#ifdef CONFIG_ESP_TLS_SERVER
#define _esp_tls_server_session_create esp_mbedtls_server_session_create
#define _esp_tls_server_session_delete esp_mbedtls_server_session_delete
#endif /* CONFIG_ESP_TLS_SERVER */
#define _esp_tls_get_bytes_avail esp_mbedtls_get_bytes_avail
#define _esp_tls_init_global_ca_store esp_mbedtls_init_global_ca_store
#define _esp_tls_set_global_ca_store esp_mbedtls_set_global_ca_store /*!< Callback function for setting global CA store data for TLS/SSL */
#define _esp_tls_get_global_ca_store esp_mbedtls_get_global_ca_store
#define _esp_tls_free_global_ca_store esp_mbedtls_free_global_ca_store /*!< Callback function for freeing global ca store for TLS/SSL */
#elif CONFIG_ESP_TLS_USING_WOLFSSL /* CONFIG_ESP_TLS_USING_MBEDTLS */
#define _esp_create_ssl_handle esp_create_wolfssl_handle
#define _esp_tls_handshake esp_wolfssl_handshake
#define _esp_tls_read esp_wolfssl_read
#define _esp_tls_write esp_wolfssl_write
#define _esp_tls_conn_delete esp_wolfssl_conn_delete
#ifdef CONFIG_ESP_TLS_SERVER
#define _esp_tls_server_session_create esp_wolfssl_server_session_create
#define _esp_tls_server_session_delete esp_wolfssl_server_session_delete
#endif /* CONFIG_ESP_TLS_SERVER */
#define _esp_tls_get_bytes_avail esp_wolfssl_get_bytes_avail
#define _esp_tls_init_global_ca_store esp_wolfssl_init_global_ca_store
#define _esp_tls_set_global_ca_store esp_wolfssl_set_global_ca_store /*!< Callback function for setting global CA store data for TLS/SSL */
#define _esp_tls_free_global_ca_store esp_wolfssl_free_global_ca_store /*!< Callback function for freeing global ca store for TLS/SSL */
#else /* ESP_TLS_USING_WOLFSSL */
#error "No TLS stack configured"
#endif
static esp_err_t create_ssl_handle(const char *hostname, size_t hostlen, const void *cfg, esp_tls_t *tls)
{
return _esp_create_ssl_handle(hostname, hostlen, cfg, tls);
}
static esp_err_t esp_tls_handshake(esp_tls_t *tls, const esp_tls_cfg_t *cfg)
{
return _esp_tls_handshake(tls, cfg);
}
static ssize_t tcp_read(esp_tls_t *tls, char *data, size_t datalen)
{
return recv(tls->sockfd, data, datalen, 0);
}
static ssize_t tcp_write(esp_tls_t *tls, const char *data, size_t datalen)
{
return send(tls->sockfd, data, datalen, 0);
}
/**
* @brief Close the TLS connection and free any allocated resources.
*/
void esp_tls_conn_delete(esp_tls_t *tls)
{
if (tls != NULL) {
_esp_tls_conn_delete(tls);
if (tls->sockfd >= 0) {
close(tls->sockfd);
}
free(tls->error_handle);
free(tls);
}
}
esp_tls_t *esp_tls_init(void)
{
esp_tls_t *tls = (esp_tls_t *)calloc(1, sizeof(esp_tls_t));
if (!tls) {
return NULL;
}
tls->error_handle = calloc(1, sizeof(esp_tls_last_error_t));
if (!tls->error_handle) {
free(tls);
return NULL;
}
#ifdef CONFIG_ESP_TLS_USING_MBEDTLS
tls->server_fd.fd = -1;
#endif
tls->sockfd = -1;
return tls;
}
static esp_err_t resolve_host_name(const char *host, size_t hostlen, struct addrinfo **address_info)
{
struct addrinfo hints;
memset(&hints, 0, sizeof(hints));
hints.ai_family = AF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
char *use_host = strndup(host, hostlen);
if (!use_host) {
return ESP_ERR_NO_MEM;
}
ESP_LOGD(TAG, "host:%s: strlen %lu", use_host, (unsigned long)hostlen);
if (getaddrinfo(use_host, NULL, &hints, address_info)) {
ESP_LOGE(TAG, "couldn't get hostname for :%s:", use_host);
free(use_host);
return ESP_ERR_ESP_TLS_CANNOT_RESOLVE_HOSTNAME;
}
free(use_host);
return ESP_OK;
}
static void ms_to_timeval(int timeout_ms, struct timeval *tv)
{
tv->tv_sec = timeout_ms / 1000;
tv->tv_usec = (timeout_ms % 1000) * 1000;
}
static esp_err_t esp_tcp_connect(const char *host, int hostlen, int port, int *sockfd, const esp_tls_t *tls, const esp_tls_cfg_t *cfg)
{
esp_err_t ret;
struct addrinfo *addrinfo;
if ((ret = resolve_host_name(host, hostlen, &addrinfo)) != ESP_OK) {
return ret;
}
int fd = socket(addrinfo->ai_family, addrinfo->ai_socktype, addrinfo->ai_protocol);
if (fd < 0) {
ESP_LOGE(TAG, "Failed to create socket (family %d socktype %d protocol %d)", addrinfo->ai_family, addrinfo->ai_socktype, addrinfo->ai_protocol);
ESP_INT_EVENT_TRACKER_CAPTURE(tls->error_handle, ERR_TYPE_SYSTEM, errno);
ret = ESP_ERR_ESP_TLS_CANNOT_CREATE_SOCKET;
goto err_freeaddr;
}
void *addr_ptr;
if (addrinfo->ai_family == AF_INET) {
struct sockaddr_in *p = (struct sockaddr_in *)addrinfo->ai_addr;
p->sin_port = htons(port);
addr_ptr = p;
} else if (addrinfo->ai_family == AF_INET6) {
struct sockaddr_in6 *p = (struct sockaddr_in6 *)addrinfo->ai_addr;
p->sin6_port = htons(port);
p->sin6_family = AF_INET6;
addr_ptr = p;
} else {
ESP_LOGE(TAG, "Unsupported protocol family %d", addrinfo->ai_family);
ret = ESP_ERR_ESP_TLS_UNSUPPORTED_PROTOCOL_FAMILY;
goto err_freesocket;
}
if (cfg) {
if (cfg->timeout_ms >= 0) {
struct timeval tv;
ms_to_timeval(cfg->timeout_ms, &tv);
setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv));
setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv));
}
if (cfg->non_block) {
int flags = fcntl(fd, F_GETFL, 0);
ret = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
if (ret < 0) {
ESP_LOGE(TAG, "Failed to configure the socket as non-blocking (errno %d)", errno);
goto err_freesocket;
}
}
}
ret = connect(fd, addr_ptr, addrinfo->ai_addrlen);
if (ret < 0 && !(errno == EINPROGRESS && cfg && cfg->non_block)) {
ESP_LOGE(TAG, "Failed to connnect to host (errno %d)", errno);
ESP_INT_EVENT_TRACKER_CAPTURE(tls->error_handle, ERR_TYPE_SYSTEM, errno);
ret = ESP_ERR_ESP_TLS_FAILED_CONNECT_TO_HOST;
goto err_freesocket;
}
*sockfd = fd;
freeaddrinfo(addrinfo);
return ESP_OK;
err_freesocket:
close(fd);
err_freeaddr:
freeaddrinfo(addrinfo);
return ret;
}
static int esp_tls_low_level_conn(const char *hostname, int hostlen, int port, const esp_tls_cfg_t *cfg, esp_tls_t *tls)
{
if (!tls) {
ESP_LOGE(TAG, "empty esp_tls parameter");
return -1;
}
esp_err_t esp_ret;
/* These states are used to keep a tab on connection progress in case of non-blocking connect,
and in case of blocking connect these cases will get executed one after the other */
switch (tls->conn_state) {
case ESP_TLS_INIT:
tls->sockfd = -1;
if (cfg != NULL) {
#ifdef CONFIG_ESP_TLS_USING_MBEDTLS
mbedtls_net_init(&tls->server_fd);
#endif
tls->is_tls = true;
}
if ((esp_ret = esp_tcp_connect(hostname, hostlen, port, &tls->sockfd, tls, cfg)) != ESP_OK) {
ESP_INT_EVENT_TRACKER_CAPTURE(tls->error_handle, ERR_TYPE_ESP, esp_ret);
return -1;
}
if (!cfg) {
tls->read = tcp_read;
tls->write = tcp_write;
ESP_LOGD(TAG, "non-tls connection established");
return 1;
}
if (cfg->non_block) {
FD_ZERO(&tls->rset);
FD_SET(tls->sockfd, &tls->rset);
tls->wset = tls->rset;
}
tls->conn_state = ESP_TLS_CONNECTING;
/* falls through */
case ESP_TLS_CONNECTING:
if (cfg->non_block) {
ESP_LOGD(TAG, "connecting...");
struct timeval tv;
ms_to_timeval(cfg->timeout_ms, &tv);
/* In case of non-blocking I/O, we use the select() API to check whether
connection has been established or not*/
if (select(tls->sockfd + 1, &tls->rset, &tls->wset, NULL,
cfg->timeout_ms>0 ? &tv : NULL) == 0) {
ESP_LOGD(TAG, "select() timed out");
return 0;
}
if (FD_ISSET(tls->sockfd, &tls->rset) || FD_ISSET(tls->sockfd, &tls->wset)) {
int error;
unsigned int len = sizeof(error);
/* pending error check */
if (getsockopt(tls->sockfd, SOL_SOCKET, SO_ERROR, &error, &len) < 0) {
ESP_LOGD(TAG, "Non blocking connect failed");
ESP_INT_EVENT_TRACKER_CAPTURE(tls->error_handle, ERR_TYPE_SYSTEM, errno);
ESP_INT_EVENT_TRACKER_CAPTURE(tls->error_handle, ERR_TYPE_ESP, ESP_ERR_ESP_TLS_SOCKET_SETOPT_FAILED);
tls->conn_state = ESP_TLS_FAIL;
return -1;
}
}
}
/* By now, the connection has been established */
esp_ret = create_ssl_handle(hostname, hostlen, cfg, tls);
if (esp_ret != ESP_OK) {
ESP_LOGE(TAG, "create_ssl_handle failed");
ESP_INT_EVENT_TRACKER_CAPTURE(tls->error_handle, ERR_TYPE_ESP, esp_ret);
tls->conn_state = ESP_TLS_FAIL;
return -1;
}
tls->read = _esp_tls_read;
tls->write = _esp_tls_write;
tls->conn_state = ESP_TLS_HANDSHAKE;
/* falls through */
case ESP_TLS_HANDSHAKE:
ESP_LOGD(TAG, "handshake in progress...");
return esp_tls_handshake(tls, cfg);
break;
case ESP_TLS_FAIL:
ESP_LOGE(TAG, "failed to open a new connection");;
break;
default:
ESP_LOGE(TAG, "invalid esp-tls state");
break;
}
return -1;
}
/**
* @brief Create a new TLS/SSL connection
*/
esp_tls_t *esp_tls_conn_new(const char *hostname, int hostlen, int port, const esp_tls_cfg_t *cfg)
{
esp_tls_t *tls = esp_tls_init();
if (!tls) {
return NULL;
}
/* esp_tls_conn_new() API establishes connection in a blocking manner thus this loop ensures that esp_tls_conn_new()
API returns only after connection is established unless there is an error*/
size_t start = xTaskGetTickCount();
while (1) {
int ret = esp_tls_low_level_conn(hostname, hostlen, port, cfg, tls);
if (ret == 1) {
return tls;
} else if (ret == -1) {
esp_tls_conn_delete(tls);
ESP_LOGE(TAG, "Failed to open new connection");
return NULL;
} else if (ret == 0 && cfg->timeout_ms >= 0) {
size_t timeout_ticks = pdMS_TO_TICKS(cfg->timeout_ms);
uint32_t expired = xTaskGetTickCount() - start;
if (expired >= timeout_ticks) {
esp_tls_conn_delete(tls);
ESP_LOGE(TAG, "Failed to open new connection in specified timeout");
return NULL;
}
}
}
return NULL;
}
int esp_tls_conn_new_sync(const char *hostname, int hostlen, int port, const esp_tls_cfg_t *cfg, esp_tls_t *tls)
{
/* esp_tls_conn_new_sync() is a sync alternative to esp_tls_conn_new_async() with symmetric function prototype
it is an alternative to esp_tls_conn_new() which is left for compatibility reasons */
size_t start = xTaskGetTickCount();
while (1) {
int ret = esp_tls_low_level_conn(hostname, hostlen, port, cfg, tls);
if (ret == 1) {
return ret;
} else if (ret == -1) {
ESP_LOGE(TAG, "Failed to open new connection");
return -1;
} else if (ret == 0 && cfg->timeout_ms >= 0) {
size_t timeout_ticks = pdMS_TO_TICKS(cfg->timeout_ms);
uint32_t expired = xTaskGetTickCount() - start;
if (expired >= timeout_ticks) {
ESP_LOGW(TAG, "Failed to open new connection in specified timeout");
ESP_INT_EVENT_TRACKER_CAPTURE(tls->error_handle, ERR_TYPE_ESP, ESP_ERR_ESP_TLS_CONNECTION_TIMEOUT);
return 0;
}
}
}
return 0;
}
/*
* @brief Create a new TLS/SSL non-blocking connection
*/
int esp_tls_conn_new_async(const char *hostname, int hostlen, int port, const esp_tls_cfg_t *cfg, esp_tls_t *tls)
{
return esp_tls_low_level_conn(hostname, hostlen, port, cfg, tls);
}
static int get_port(const char *url, struct http_parser_url *u)
{
if (u->field_data[UF_PORT].len) {
return strtol(&url[u->field_data[UF_PORT].off], NULL, 10);
} else {
if (strncasecmp(&url[u->field_data[UF_SCHEMA].off], "http", u->field_data[UF_SCHEMA].len) == 0) {
return 80;
} else if (strncasecmp(&url[u->field_data[UF_SCHEMA].off], "https", u->field_data[UF_SCHEMA].len) == 0) {
return 443;
}
}
return 0;
}
/**
* @brief Create a new TLS/SSL connection with a given "HTTP" url
*/
esp_tls_t *esp_tls_conn_http_new(const char *url, const esp_tls_cfg_t *cfg)
{
/* Parse URI */
struct http_parser_url u;
http_parser_url_init(&u);
http_parser_parse_url(url, strlen(url), 0, &u);
esp_tls_t *tls = esp_tls_init();
if (!tls) {
return NULL;
}
/* Connect to host */
if (esp_tls_conn_new_sync(&url[u.field_data[UF_HOST].off], u.field_data[UF_HOST].len,
get_port(url, &u), cfg, tls) == 1) {
return tls;
}
esp_tls_conn_delete(tls);
return NULL;
}
/**
* @brief Create a new non-blocking TLS/SSL connection with a given "HTTP" url
*/
int esp_tls_conn_http_new_async(const char *url, const esp_tls_cfg_t *cfg, esp_tls_t *tls)
{
/* Parse URI */
struct http_parser_url u;
http_parser_url_init(&u);
http_parser_parse_url(url, strlen(url), 0, &u);
/* Connect to host */
return esp_tls_conn_new_async(&url[u.field_data[UF_HOST].off], u.field_data[UF_HOST].len,
get_port(url, &u), cfg, tls);
}
#ifdef CONFIG_ESP_TLS_USING_MBEDTLS
mbedtls_x509_crt *esp_tls_get_global_ca_store(void)
{
return _esp_tls_get_global_ca_store();
}
#endif /* CONFIG_ESP_TLS_USING_MBEDTLS */
#ifdef CONFIG_ESP_TLS_SERVER
/**
* @brief Create a server side TLS/SSL connection
*/
int esp_tls_server_session_create(esp_tls_cfg_server_t *cfg, int sockfd, esp_tls_t *tls)
{
return _esp_tls_server_session_create(cfg, sockfd, tls);
}
/**
* @brief Close the server side TLS/SSL connection and free any allocated resources.
*/
void esp_tls_server_session_delete(esp_tls_t *tls)
{
return _esp_tls_server_session_delete(tls);
}
#endif /* CONFIG_ESP_TLS_SERVER */
ssize_t esp_tls_get_bytes_avail(esp_tls_t *tls)
{
return _esp_tls_get_bytes_avail(tls);
}
esp_err_t esp_tls_get_conn_sockfd(esp_tls_t *tls, int *sockfd)
{
if (!tls || !sockfd) {
ESP_LOGE(TAG, "Invalid arguments passed");
return ESP_ERR_INVALID_ARG;
}
*sockfd = tls->sockfd;
return ESP_OK;
}
esp_err_t esp_tls_get_and_clear_last_error(esp_tls_error_handle_t h, int *esp_tls_code, int *esp_tls_flags)
{
if (!h) {
return ESP_ERR_INVALID_STATE;
}
esp_err_t last_err = h->last_error;
if (esp_tls_code) {
*esp_tls_code = h->esp_tls_error_code;
}
if (esp_tls_flags) {
*esp_tls_flags = h->esp_tls_flags;
}
memset(h, 0, sizeof(esp_tls_last_error_t));
return last_err;
}
esp_err_t esp_tls_init_global_ca_store(void)
{
return _esp_tls_init_global_ca_store();
}
esp_err_t esp_tls_set_global_ca_store(const unsigned char *cacert_pem_buf, const unsigned int cacert_pem_bytes)
{
return _esp_tls_set_global_ca_store(cacert_pem_buf, cacert_pem_bytes);
}
void esp_tls_free_global_ca_store(void)
{
return _esp_tls_free_global_ca_store();
}