/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
* Copyright (C) Hoi-Ho Chan, <hoiho.chan@gmail.com>
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
/*
* Source file for all mbedTLS-specific code for the TLS/SSL layer. No code
* but vtls.c should ever call or use these functions.
*
*/
#include "curl_setup.h"
#ifdef USE_MBEDTLS
/* Define this to enable lots of debugging for mbedTLS */
/* #define MBEDTLS_DEBUG */
#include <mbedtls/version.h>
#if MBEDTLS_VERSION_NUMBER >= 0x02040000
#include <mbedtls/net_sockets.h>
#else
#include <mbedtls/net.h>
#endif
#include <mbedtls/ssl.h>
#include <mbedtls/x509.h>
#include <mbedtls/error.h>
#include <mbedtls/entropy.h>
#include <mbedtls/ctr_drbg.h>
#include <mbedtls/sha256.h>
#if MBEDTLS_VERSION_MAJOR >= 2
# ifdef MBEDTLS_DEBUG
# include <mbedtls/debug.h>
# endif
#endif
#include "urldata.h"
#include "sendf.h"
#include "inet_pton.h"
#include "mbedtls.h"
#include "vtls.h"
#include "vtls_int.h"
#include "parsedate.h"
#include "connect.h" /* for the connect timeout */
#include "select.h"
#include "multiif.h"
#include "mbedtls_threadlock.h"
/* The last 3 #include files should be in this order */
#include "curl_printf.h"
#include "curl_memory.h"
#include "memdebug.h"
/* ALPN for http2 */
#ifdef USE_HTTP2
# undef HAS_ALPN
# ifdef MBEDTLS_SSL_ALPN
# define HAS_ALPN
# endif
#endif
struct mbed_ssl_backend_data {
mbedtls_ctr_drbg_context ctr_drbg;
mbedtls_entropy_context entropy;
mbedtls_ssl_context ssl;
mbedtls_x509_crt cacert;
mbedtls_x509_crt clicert;
#ifdef MBEDTLS_X509_CRL_PARSE_C
mbedtls_x509_crl crl;
#endif
mbedtls_pk_context pk;
mbedtls_ssl_config config;
#ifdef HAS_ALPN
const char *protocols[3];
#endif
};
/* apply threading? */
#if defined(USE_THREADS_POSIX) || defined(USE_THREADS_WIN32)
#define THREADING_SUPPORT
#endif
#ifndef MBEDTLS_ERROR_C
#define mbedtls_strerror(a,b,c) b[0] = 0
#endif
#if defined(THREADING_SUPPORT)
static mbedtls_entropy_context ts_entropy;
static int entropy_init_initialized = 0;
/* start of entropy_init_mutex() */
static void entropy_init_mutex(mbedtls_entropy_context *ctx)
{
/* lock 0 = entropy_init_mutex() */
Curl_mbedtlsthreadlock_lock_function(0);
if(entropy_init_initialized == 0) {
mbedtls_entropy_init(ctx);
entropy_init_initialized = 1;
}
Curl_mbedtlsthreadlock_unlock_function(0);
}
/* end of entropy_init_mutex() */
/* start of entropy_func_mutex() */
static int entropy_func_mutex(void *data, unsigned char *output, size_t len)
{
int ret;
/* lock 1 = entropy_func_mutex() */
Curl_mbedtlsthreadlock_lock_function(1);
ret = mbedtls_entropy_func(data, output, len);
Curl_mbedtlsthreadlock_unlock_function(1);
return ret;
}
/* end of entropy_func_mutex() */
#endif /* THREADING_SUPPORT */
#ifdef MBEDTLS_DEBUG
static void mbed_debug(void *context, int level, const char *f_name,
int line_nb, const char *line)
{
struct Curl_easy *data = NULL;
if(!context)
return;
data = (struct Curl_easy *)context;
infof(data, "%s", line);
(void) level;
}
#else
#endif
static int mbedtls_bio_cf_write(void *bio,
const unsigned char *buf, size_t blen)
{
struct Curl_cfilter *cf = bio;
struct Curl_easy *data = CF_DATA_CURRENT(cf);
ssize_t nwritten;
CURLcode result;
DEBUGASSERT(data);
nwritten = Curl_conn_cf_send(cf->next, data, (char *)buf, blen, &result);
CURL_TRC_CF(data, cf, "mbedtls_bio_cf_out_write(len=%zu) -> %zd, err=%d",
blen, nwritten, result);
if(nwritten < 0 && CURLE_AGAIN == result) {
nwritten = MBEDTLS_ERR_SSL_WANT_WRITE;
}
return (int)nwritten;
}
static int mbedtls_bio_cf_read(void *bio, unsigned char *buf, size_t blen)
{
struct Curl_cfilter *cf = bio;
struct Curl_easy *data = CF_DATA_CURRENT(cf);
ssize_t nread;
CURLcode result;
DEBUGASSERT(data);
/* OpenSSL catches this case, so should we. */
if(!buf)
return 0;
nread = Curl_conn_cf_recv(cf->next, data, (char *)buf, blen, &result);
CURL_TRC_CF(data, cf, "mbedtls_bio_cf_in_read(len=%zu) -> %zd, err=%d",
blen, nread, result);
if(nread < 0 && CURLE_AGAIN == result) {
nread = MBEDTLS_ERR_SSL_WANT_READ;
}
return (int)nread;
}
/*
* profile
*/
static const mbedtls_x509_crt_profile mbedtls_x509_crt_profile_fr =
{
/* Hashes from SHA-1 and above */
MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA1) |
MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_RIPEMD160) |
MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA224) |
MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA256) |
MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA384) |
MBEDTLS_X509_ID_FLAG(MBEDTLS_MD_SHA512),
0xFFFFFFF, /* Any PK alg */
0xFFFFFFF, /* Any curve */
1024, /* RSA min key len */
};
/* See https://tls.mbed.org/discussions/generic/
howto-determine-exact-buffer-len-for-mbedtls_pk_write_pubkey_der
*/
#define RSA_PUB_DER_MAX_BYTES (38 + 2 * MBEDTLS_MPI_MAX_SIZE)
#define ECP_PUB_DER_MAX_BYTES (30 + 2 * MBEDTLS_ECP_MAX_BYTES)
#define PUB_DER_MAX_BYTES (RSA_PUB_DER_MAX_BYTES > ECP_PUB_DER_MAX_BYTES ? \
RSA_PUB_DER_MAX_BYTES : ECP_PUB_DER_MAX_BYTES)
static CURLcode mbedtls_version_from_curl(int *mbedver, long version)
{
#if MBEDTLS_VERSION_NUMBER >= 0x03000000
switch(version) {
case CURL_SSLVERSION_TLSv1_0:
case CURL_SSLVERSION_TLSv1_1:
case CURL_SSLVERSION_TLSv1_2:
*mbedver = MBEDTLS_SSL_MINOR_VERSION_3;
return CURLE_OK;
case CURL_SSLVERSION_TLSv1_3:
break;
}
#else
switch(version) {
case CURL_SSLVERSION_TLSv1_0:
*mbedver = MBEDTLS_SSL_MINOR_VERSION_1;
return CURLE_OK;
case CURL_SSLVERSION_TLSv1_1:
*mbedver = MBEDTLS_SSL_MINOR_VERSION_2;
return CURLE_OK;
case CURL_SSLVERSION_TLSv1_2:
*mbedver = MBEDTLS_SSL_MINOR_VERSION_3;
return CURLE_OK;
case CURL_SSLVERSION_TLSv1_3:
break;
}
#endif
return CURLE_SSL_CONNECT_ERROR;
}
static CURLcode
set_ssl_version_min_max(struct Curl_cfilter *cf, struct Curl_easy *data)
{
struct ssl_connect_data *connssl = cf->ctx;
struct mbed_ssl_backend_data *backend =
(struct mbed_ssl_backend_data *)connssl->backend;
struct ssl_primary_config *conn_config = Curl_ssl_cf_get_primary_config(cf);
#if MBEDTLS_VERSION_NUMBER >= 0x03000000
int mbedtls_ver_min = MBEDTLS_SSL_MINOR_VERSION_3;
int mbedtls_ver_max = MBEDTLS_SSL_MINOR_VERSION_3;
#else
int mbedtls_ver_min = MBEDTLS_SSL_MINOR_VERSION_1;
int mbedtls_ver_max = MBEDTLS_SSL_MINOR_VERSION_1;
#endif
long ssl_version = conn_config->version;
long ssl_version_max = conn_config->version_max;
CURLcode result = CURLE_OK;
DEBUGASSERT(backend);
switch(ssl_version) {
case CURL_SSLVERSION_DEFAULT:
case CURL_SSLVERSION_TLSv1:
ssl_version = CURL_SSLVERSION_TLSv1_0;
break;
}
switch(ssl_version_max) {
case CURL_SSLVERSION_MAX_NONE:
case CURL_SSLVERSION_MAX_DEFAULT:
ssl_version_max = CURL_SSLVERSION_MAX_TLSv1_2;
break;
}
result = mbedtls_version_from_curl(&mbedtls_ver_min, ssl_version);
if(result) {
failf(data, "unsupported min version passed via CURLOPT_SSLVERSION");
return result;
}
result = mbedtls_version_from_curl(&mbedtls_ver_max, ssl_version_max >> 16);
if(result) {
failf(data, "unsupported max version passed via CURLOPT_SSLVERSION");
return result;
}
mbedtls_ssl_conf_min_version(&backend->config, MBEDTLS_SSL_MAJOR_VERSION_3,
mbedtls_ver_min);
mbedtls_ssl_conf_max_version(&backend->config, MBEDTLS_SSL_MAJOR_VERSION_3,
mbedtls_ver_max);
return result;
}
static CURLcode
mbed_connect_step1(struct Curl_cfilter *cf, struct Curl_easy *data)
{
struct ssl_connect_data *connssl = cf->ctx;
struct mbed_ssl_backend_data *backend =
(struct mbed_ssl_backend_data *)connssl->backend;
struct ssl_primary_config *conn_config = Curl_ssl_cf_get_primary_config(cf);
const struct curl_blob *ca_info_blob = conn_config->ca_info_blob;
struct ssl_config_data *ssl_config = Curl_ssl_cf_get_config(cf, data);
const char * const ssl_cafile =
/* CURLOPT_CAINFO_BLOB overrides CURLOPT_CAINFO */
(ca_info_blob ? NULL : conn_config->CAfile);
const bool verifypeer = conn_config->verifypeer;
const char * const ssl_capath = conn_config->CApath;
char * const ssl_cert = ssl_config->primary.clientcert;
const struct curl_blob *ssl_cert_blob = ssl_config->primary.cert_blob;
const char * const ssl_crlfile = ssl_config->primary.CRLfile;
const char *hostname = connssl->hostname;
int ret = -1;
char errorbuf[128];
DEBUGASSERT(backend);
if((conn_config->version == CURL_SSLVERSION_SSLv2) ||
(conn_config->version == CURL_SSLVERSION_SSLv3)) {
failf(data, "Not supported SSL version");
return CURLE_NOT_BUILT_IN;
}
#ifdef THREADING_SUPPORT
entropy_init_mutex(&ts_entropy);
mbedtls_ctr_drbg_init(&backend->ctr_drbg);
ret = mbedtls_ctr_drbg_seed(&backend->ctr_drbg, entropy_func_mutex,
&ts_entropy, NULL, 0);
if(ret) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "mbedtls_ctr_drbg_seed returned (-0x%04X) %s",
-ret, errorbuf);
return CURLE_FAILED_INIT;
}
#else
mbedtls_entropy_init(&backend->entropy);
mbedtls_ctr_drbg_init(&backend->ctr_drbg);
ret = mbedtls_ctr_drbg_seed(&backend->ctr_drbg, mbedtls_entropy_func,
&backend->entropy, NULL, 0);
if(ret) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "mbedtls_ctr_drbg_seed returned (-0x%04X) %s",
-ret, errorbuf);
return CURLE_FAILED_INIT;
}
#endif /* THREADING_SUPPORT */
/* Load the trusted CA */
mbedtls_x509_crt_init(&backend->cacert);
if(ca_info_blob && verifypeer) {
/* Unfortunately, mbedtls_x509_crt_parse() requires the data to be null
terminated even when provided the exact length, forcing us to waste
extra memory here. */
unsigned char *newblob = malloc(ca_info_blob->len + 1);
if(!newblob)
return CURLE_OUT_OF_MEMORY;
memcpy(newblob, ca_info_blob->data, ca_info_blob->len);
newblob[ca_info_blob->len] = 0; /* null terminate */
ret = mbedtls_x509_crt_parse(&backend->cacert, newblob,
ca_info_blob->len + 1);
free(newblob);
if(ret<0) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "Error importing ca cert blob - mbedTLS: (-0x%04X) %s",
-ret, errorbuf);
return CURLE_SSL_CERTPROBLEM;
}
}
if(ssl_cafile && verifypeer) {
#ifdef MBEDTLS_FS_IO
ret = mbedtls_x509_crt_parse_file(&backend->cacert, ssl_cafile);
if(ret<0) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "Error reading ca cert file %s - mbedTLS: (-0x%04X) %s",
ssl_cafile, -ret, errorbuf);
return CURLE_SSL_CACERT_BADFILE;
}
#else
failf(data, "mbedtls: functions that use the filesystem not built in");
return CURLE_NOT_BUILT_IN;
#endif
}
if(ssl_capath) {
#ifdef MBEDTLS_FS_IO
ret = mbedtls_x509_crt_parse_path(&backend->cacert, ssl_capath);
if(ret<0) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "Error reading ca cert path %s - mbedTLS: (-0x%04X) %s",
ssl_capath, -ret, errorbuf);
if(verifypeer)
return CURLE_SSL_CACERT_BADFILE;
}
#else
failf(data, "mbedtls: functions that use the filesystem not built in");
return CURLE_NOT_BUILT_IN;
#endif
}
/* Load the client certificate */
mbedtls_x509_crt_init(&backend->clicert);
if(ssl_cert) {
#ifdef MBEDTLS_FS_IO
ret = mbedtls_x509_crt_parse_file(&backend->clicert, ssl_cert);
if(ret) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "Error reading client cert file %s - mbedTLS: (-0x%04X) %s",
ssl_cert, -ret, errorbuf);
return CURLE_SSL_CERTPROBLEM;
}
#else
failf(data, "mbedtls: functions that use the filesystem not built in");
return CURLE_NOT_BUILT_IN;
#endif
}
if(ssl_cert_blob) {
/* Unfortunately, mbedtls_x509_crt_parse() requires the data to be null
terminated even when provided the exact length, forcing us to waste
extra memory here. */
unsigned char *newblob = malloc(ssl_cert_blob->len + 1);
if(!newblob)
return CURLE_OUT_OF_MEMORY;
memcpy(newblob, ssl_cert_blob->data, ssl_cert_blob->len);
newblob[ssl_cert_blob->len] = 0; /* null terminate */
ret = mbedtls_x509_crt_parse(&backend->clicert, newblob,
ssl_cert_blob->len + 1);
free(newblob);
if(ret) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "Error reading private key %s - mbedTLS: (-0x%04X) %s",
ssl_config->key, -ret, errorbuf);
return CURLE_SSL_CERTPROBLEM;
}
}
/* Load the client private key */
mbedtls_pk_init(&backend->pk);
if(ssl_config->key || ssl_config->key_blob) {
if(ssl_config->key) {
#ifdef MBEDTLS_FS_IO
#if MBEDTLS_VERSION_NUMBER >= 0x03000000
ret = mbedtls_pk_parse_keyfile(&backend->pk, ssl_config->key,
ssl_config->key_passwd,
mbedtls_ctr_drbg_random,
&backend->ctr_drbg);
#else
ret = mbedtls_pk_parse_keyfile(&backend->pk, ssl_config->key,
ssl_config->key_passwd);
#endif
if(ret) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "Error reading private key %s - mbedTLS: (-0x%04X) %s",
ssl_config->key, -ret, errorbuf);
return CURLE_SSL_CERTPROBLEM;
}
#else
failf(data, "mbedtls: functions that use the filesystem not built in");
return CURLE_NOT_BUILT_IN;
#endif
}
else {
const struct curl_blob *ssl_key_blob = ssl_config->key_blob;
const unsigned char *key_data =
(const unsigned char *)ssl_key_blob->data;
const char *passwd = ssl_config->key_passwd;
#if MBEDTLS_VERSION_NUMBER >= 0x03000000
ret = mbedtls_pk_parse_key(&backend->pk, key_data, ssl_key_blob->len,
(const unsigned char *)passwd,
passwd ? strlen(passwd) : 0,
mbedtls_ctr_drbg_random,
&backend->ctr_drbg);
#else
ret = mbedtls_pk_parse_key(&backend->pk, key_data, ssl_key_blob->len,
(const unsigned char *)passwd,
passwd ? strlen(passwd) : 0);
#endif
if(ret) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "Error parsing private key - mbedTLS: (-0x%04X) %s",
-ret, errorbuf);
return CURLE_SSL_CERTPROBLEM;
}
}
if(ret == 0 && !(mbedtls_pk_can_do(&backend->pk, MBEDTLS_PK_RSA) ||
mbedtls_pk_can_do(&backend->pk, MBEDTLS_PK_ECKEY)))
ret = MBEDTLS_ERR_PK_TYPE_MISMATCH;
}
/* Load the CRL */
#ifdef MBEDTLS_X509_CRL_PARSE_C
mbedtls_x509_crl_init(&backend->crl);
if(ssl_crlfile) {
#ifdef MBEDTLS_FS_IO
ret = mbedtls_x509_crl_parse_file(&backend->crl, ssl_crlfile);
if(ret) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "Error reading CRL file %s - mbedTLS: (-0x%04X) %s",
ssl_crlfile, -ret, errorbuf);
return CURLE_SSL_CRL_BADFILE;
}
#else
failf(data, "mbedtls: functions that use the filesystem not built in");
return CURLE_NOT_BUILT_IN;
#endif
}
#else
if(ssl_crlfile) {
failf(data, "mbedtls: crl support not built in");
return CURLE_NOT_BUILT_IN;
}
#endif
infof(data, "mbedTLS: Connecting to %s:%d", hostname, connssl->port);
mbedtls_ssl_config_init(&backend->config);
ret = mbedtls_ssl_config_defaults(&backend->config,
MBEDTLS_SSL_IS_CLIENT,
MBEDTLS_SSL_TRANSPORT_STREAM,
MBEDTLS_SSL_PRESET_DEFAULT);
if(ret) {
failf(data, "mbedTLS: ssl_config failed");
return CURLE_SSL_CONNECT_ERROR;
}
mbedtls_ssl_init(&backend->ssl);
if(mbedtls_ssl_setup(&backend->ssl, &backend->config)) {
failf(data, "mbedTLS: ssl_init failed");
return CURLE_SSL_CONNECT_ERROR;
}
/* new profile with RSA min key len = 1024 ... */
mbedtls_ssl_conf_cert_profile(&backend->config,
&mbedtls_x509_crt_profile_fr);
switch(conn_config->version) {
case CURL_SSLVERSION_DEFAULT:
case CURL_SSLVERSION_TLSv1:
#if MBEDTLS_VERSION_NUMBER < 0x03000000
mbedtls_ssl_conf_min_version(&backend->config, MBEDTLS_SSL_MAJOR_VERSION_3,
MBEDTLS_SSL_MINOR_VERSION_1);
infof(data, "mbedTLS: Set min SSL version to TLS 1.0");
break;
#endif
case CURL_SSLVERSION_TLSv1_0:
case CURL_SSLVERSION_TLSv1_1:
case CURL_SSLVERSION_TLSv1_2:
case CURL_SSLVERSION_TLSv1_3:
{
CURLcode result = set_ssl_version_min_max(cf, data);
if(result != CURLE_OK)
return result;
break;
}
default:
failf(data, "Unrecognized parameter passed via CURLOPT_SSLVERSION");
return CURLE_SSL_CONNECT_ERROR;
}
mbedtls_ssl_conf_authmode(&backend->config, MBEDTLS_SSL_VERIFY_OPTIONAL);
mbedtls_ssl_conf_rng(&backend->config, mbedtls_ctr_drbg_random,
&backend->ctr_drbg);
mbedtls_ssl_set_bio(&backend->ssl, cf,
mbedtls_bio_cf_write,
mbedtls_bio_cf_read,
NULL /* rev_timeout() */);
mbedtls_ssl_conf_ciphersuites(&backend->config,
mbedtls_ssl_list_ciphersuites());
#if defined(MBEDTLS_SSL_RENEGOTIATION)
mbedtls_ssl_conf_renegotiation(&backend->config,
MBEDTLS_SSL_RENEGOTIATION_ENABLED);
#endif
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
mbedtls_ssl_conf_session_tickets(&backend->config,
MBEDTLS_SSL_SESSION_TICKETS_DISABLED);
#endif
/* Check if there's a cached ID we can/should use here! */
if(ssl_config->primary.sessionid) {
void *old_session = NULL;
Curl_ssl_sessionid_lock(data);
if(!Curl_ssl_getsessionid(cf, data, &old_session, NULL)) {
ret = mbedtls_ssl_set_session(&backend->ssl, old_session);
if(ret) {
Curl_ssl_sessionid_unlock(data);
failf(data, "mbedtls_ssl_set_session returned -0x%x", -ret);
return CURLE_SSL_CONNECT_ERROR;
}
infof(data, "mbedTLS reusing session");
}
Curl_ssl_sessionid_unlock(data);
}
mbedtls_ssl_conf_ca_chain(&backend->config,
&backend->cacert,
#ifdef MBEDTLS_X509_CRL_PARSE_C
&backend->crl);
#else
NULL);
#endif
if(ssl_config->key || ssl_config->key_blob) {
mbedtls_ssl_conf_own_cert(&backend->config,
&backend->clicert, &backend->pk);
}
{
char *snihost = Curl_ssl_snihost(data, hostname, NULL);
if(!snihost || mbedtls_ssl_set_hostname(&backend->ssl, snihost)) {
/* mbedtls_ssl_set_hostname() sets the name to use in CN/SAN checks and
the name to set in the SNI extension. So even if curl connects to a
host specified as an IP address, this function must be used. */
failf(data, "Failed to set SNI");
return CURLE_SSL_CONNECT_ERROR;
}
}
#ifdef HAS_ALPN
if(connssl->alpn) {
struct alpn_proto_buf proto;
size_t i;
for(i = 0; i < connssl->alpn->count; ++i) {
backend->protocols[i] = connssl->alpn->entries[i];
}
/* this function doesn't clone the protocols array, which is why we need
to keep it around */
if(mbedtls_ssl_conf_alpn_protocols(&backend->config,
&backend->protocols[0])) {
failf(data, "Failed setting ALPN protocols");
return CURLE_SSL_CONNECT_ERROR;
}
Curl_alpn_to_proto_str(&proto, connssl->alpn);
infof(data, VTLS_INFOF_ALPN_OFFER_1STR, proto.data);
}
#endif
#ifdef MBEDTLS_DEBUG
/* In order to make that work in mbedtls MBEDTLS_DEBUG_C must be defined. */
mbedtls_ssl_conf_dbg(&backend->config, mbed_debug, data);
/* - 0 No debug
* - 1 Error
* - 2 State change
* - 3 Informational
* - 4 Verbose
*/
mbedtls_debug_set_threshold(4);
#endif
/* give application a chance to interfere with mbedTLS set up. */
if(data->set.ssl.fsslctx) {
ret = (*data->set.ssl.fsslctx)(data, &backend->config,
data->set.ssl.fsslctxp);
if(ret) {
failf(data, "error signaled by ssl ctx callback");
return ret;
}
}
connssl->connecting_state = ssl_connect_2;
return CURLE_OK;
}
static CURLcode
mbed_connect_step2(struct Curl_cfilter *cf, struct Curl_easy *data)
{
int ret;
struct ssl_connect_data *connssl = cf->ctx;
struct mbed_ssl_backend_data *backend =
(struct mbed_ssl_backend_data *)connssl->backend;
struct ssl_primary_config *conn_config = Curl_ssl_cf_get_primary_config(cf);
const mbedtls_x509_crt *peercert;
const char * const pinnedpubkey = Curl_ssl_cf_is_proxy(cf)?
data->set.str[STRING_SSL_PINNEDPUBLICKEY_PROXY]:
data->set.str[STRING_SSL_PINNEDPUBLICKEY];
DEBUGASSERT(backend);
ret = mbedtls_ssl_handshake(&backend->ssl);
if(ret == MBEDTLS_ERR_SSL_WANT_READ) {
connssl->connecting_state = ssl_connect_2_reading;
return CURLE_OK;
}
else if(ret == MBEDTLS_ERR_SSL_WANT_WRITE) {
connssl->connecting_state = ssl_connect_2_writing;
return CURLE_OK;
}
else if(ret) {
char errorbuf[128];
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "ssl_handshake returned - mbedTLS: (-0x%04X) %s",
-ret, errorbuf);
return CURLE_SSL_CONNECT_ERROR;
}
infof(data, "mbedTLS: Handshake complete, cipher is %s",
mbedtls_ssl_get_ciphersuite(&backend->ssl));
ret = mbedtls_ssl_get_verify_result(&backend->ssl);
if(!conn_config->verifyhost)
/* Ignore hostname errors if verifyhost is disabled */
ret &= ~MBEDTLS_X509_BADCERT_CN_MISMATCH;
if(ret && conn_config->verifypeer) {
if(ret & MBEDTLS_X509_BADCERT_EXPIRED)
failf(data, "Cert verify failed: BADCERT_EXPIRED");
else if(ret & MBEDTLS_X509_BADCERT_REVOKED)
failf(data, "Cert verify failed: BADCERT_REVOKED");
else if(ret & MBEDTLS_X509_BADCERT_CN_MISMATCH)
failf(data, "Cert verify failed: BADCERT_CN_MISMATCH");
else if(ret & MBEDTLS_X509_BADCERT_NOT_TRUSTED)
failf(data, "Cert verify failed: BADCERT_NOT_TRUSTED");
else if(ret & MBEDTLS_X509_BADCERT_FUTURE)
failf(data, "Cert verify failed: BADCERT_FUTURE");
return CURLE_PEER_FAILED_VERIFICATION;
}
peercert = mbedtls_ssl_get_peer_cert(&backend->ssl);
if(peercert && data->set.verbose) {
const size_t bufsize = 16384;
char *buffer = malloc(bufsize);
if(!buffer)
return CURLE_OUT_OF_MEMORY;
if(mbedtls_x509_crt_info(buffer, bufsize, "* ", peercert) > 0)
infof(data, "Dumping cert info: %s", buffer);
else
infof(data, "Unable to dump certificate information");
free(buffer);
}
if(pinnedpubkey) {
int size;
CURLcode result;
mbedtls_x509_crt *p = NULL;
unsigned char *pubkey = NULL;
#if MBEDTLS_VERSION_NUMBER == 0x03000000
if(!peercert || !peercert->MBEDTLS_PRIVATE(raw).MBEDTLS_PRIVATE(p) ||
!peercert->MBEDTLS_PRIVATE(raw).MBEDTLS_PRIVATE(len)) {
#else
if(!peercert || !peercert->raw.p || !peercert->raw.len) {
#endif
failf(data, "Failed due to missing peer certificate");
return CURLE_SSL_PINNEDPUBKEYNOTMATCH;
}
p = calloc(1, sizeof(*p));
if(!p)
return CURLE_OUT_OF_MEMORY;
pubkey = malloc(PUB_DER_MAX_BYTES);
if(!pubkey) {
result = CURLE_OUT_OF_MEMORY;
goto pinnedpubkey_error;
}
mbedtls_x509_crt_init(p);
/* Make a copy of our const peercert because mbedtls_pk_write_pubkey_der
needs a non-const key, for now.
https://github.com/ARMmbed/mbedtls/issues/396 */
#if MBEDTLS_VERSION_NUMBER == 0x03000000
if(mbedtls_x509_crt_parse_der(p,
peercert->MBEDTLS_PRIVATE(raw).MBEDTLS_PRIVATE(p),
peercert->MBEDTLS_PRIVATE(raw).MBEDTLS_PRIVATE(len))) {
#else
if(mbedtls_x509_crt_parse_der(p, peercert->raw.p, peercert->raw.len)) {
#endif
failf(data, "Failed copying peer certificate");
result = CURLE_SSL_PINNEDPUBKEYNOTMATCH;
goto pinnedpubkey_error;
}
#if MBEDTLS_VERSION_NUMBER == 0x03000000
size = mbedtls_pk_write_pubkey_der(&p->MBEDTLS_PRIVATE(pk), pubkey,
PUB_DER_MAX_BYTES);
#else
size = mbedtls_pk_write_pubkey_der(&p->pk, pubkey, PUB_DER_MAX_BYTES);
#endif
if(size <= 0) {
failf(data, "Failed copying public key from peer certificate");
result = CURLE_SSL_PINNEDPUBKEYNOTMATCH;
goto pinnedpubkey_error;
}
/* mbedtls_pk_write_pubkey_der writes data at the end of the buffer. */
result = Curl_pin_peer_pubkey(data,
pinnedpubkey,
&pubkey[PUB_DER_MAX_BYTES - size], size);
pinnedpubkey_error:
mbedtls_x509_crt_free(p);
free(p);
free(pubkey);
if(result) {
return result;
}
}
#ifdef HAS_ALPN
if(connssl->alpn) {
const char *proto = mbedtls_ssl_get_alpn_protocol(&backend->ssl);
Curl_alpn_set_negotiated(cf, data, (const unsigned char *)proto,
proto? strlen(proto) : 0);
}
#endif
connssl->connecting_state = ssl_connect_3;
infof(data, "SSL connected");
return CURLE_OK;
}
static CURLcode
mbed_connect_step3(struct Curl_cfilter *cf, struct Curl_easy *data)
{
CURLcode retcode = CURLE_OK;
struct ssl_connect_data *connssl = cf->ctx;
struct mbed_ssl_backend_data *backend =
(struct mbed_ssl_backend_data *)connssl->backend;
struct ssl_config_data *ssl_config = Curl_ssl_cf_get_config(cf, data);
DEBUGASSERT(ssl_connect_3 == connssl->connecting_state);
DEBUGASSERT(backend);
if(ssl_config->primary.sessionid) {
int ret;
mbedtls_ssl_session *our_ssl_sessionid;
void *old_ssl_sessionid = NULL;
bool added = FALSE;
our_ssl_sessionid = malloc(sizeof(mbedtls_ssl_session));
if(!our_ssl_sessionid)
return CURLE_OUT_OF_MEMORY;
mbedtls_ssl_session_init(our_ssl_sessionid);
ret = mbedtls_ssl_get_session(&backend->ssl, our_ssl_sessionid);
if(ret) {
if(ret != MBEDTLS_ERR_SSL_ALLOC_FAILED)
mbedtls_ssl_session_free(our_ssl_sessionid);
free(our_ssl_sessionid);
failf(data, "mbedtls_ssl_get_session returned -0x%x", -ret);
return CURLE_SSL_CONNECT_ERROR;
}
/* If there's already a matching session in the cache, delete it */
Curl_ssl_sessionid_lock(data);
if(!Curl_ssl_getsessionid(cf, data, &old_ssl_sessionid, NULL))
Curl_ssl_delsessionid(data, old_ssl_sessionid);
retcode = Curl_ssl_addsessionid(cf, data, our_ssl_sessionid,
0, &added);
Curl_ssl_sessionid_unlock(data);
if(!added) {
mbedtls_ssl_session_free(our_ssl_sessionid);
free(our_ssl_sessionid);
}
if(retcode) {
failf(data, "failed to store ssl session");
return retcode;
}
}
connssl->connecting_state = ssl_connect_done;
return CURLE_OK;
}
static ssize_t mbed_send(struct Curl_cfilter *cf, struct Curl_easy *data,
const void *mem, size_t len,
CURLcode *curlcode)
{
struct ssl_connect_data *connssl = cf->ctx;
struct mbed_ssl_backend_data *backend =
(struct mbed_ssl_backend_data *)connssl->backend;
int ret = -1;
(void)data;
DEBUGASSERT(backend);
ret = mbedtls_ssl_write(&backend->ssl, (unsigned char *)mem, len);
if(ret < 0) {
*curlcode = (ret == MBEDTLS_ERR_SSL_WANT_WRITE) ?
CURLE_AGAIN : CURLE_SEND_ERROR;
ret = -1;
}
return ret;
}
static void mbedtls_close_all(struct Curl_easy *data)
{
(void)data;
}
static void mbedtls_close(struct Curl_cfilter *cf, struct Curl_easy *data)
{
struct ssl_connect_data *connssl = cf->ctx;
struct mbed_ssl_backend_data *backend =
(struct mbed_ssl_backend_data *)connssl->backend;
char buf[32];
(void)data;
DEBUGASSERT(backend);
/* Maybe the server has already sent a close notify alert.
Read it to avoid an RST on the TCP connection. */
(void)mbedtls_ssl_read(&backend->ssl, (unsigned char *)buf, sizeof(buf));
mbedtls_pk_free(&backend->pk);
mbedtls_x509_crt_free(&backend->clicert);
mbedtls_x509_crt_free(&backend->cacert);
#ifdef MBEDTLS_X509_CRL_PARSE_C
mbedtls_x509_crl_free(&backend->crl);
#endif
mbedtls_ssl_config_free(&backend->config);
mbedtls_ssl_free(&backend->ssl);
mbedtls_ctr_drbg_free(&backend->ctr_drbg);
#ifndef THREADING_SUPPORT
mbedtls_entropy_free(&backend->entropy);
#endif /* THREADING_SUPPORT */
}
static ssize_t mbed_recv(struct Curl_cfilter *cf, struct Curl_easy *data,
char *buf, size_t buffersize,
CURLcode *curlcode)
{
struct ssl_connect_data *connssl = cf->ctx;
struct mbed_ssl_backend_data *backend =
(struct mbed_ssl_backend_data *)connssl->backend;
int ret = -1;
ssize_t len = -1;
(void)data;
DEBUGASSERT(backend);
ret = mbedtls_ssl_read(&backend->ssl, (unsigned char *)buf,
buffersize);
if(ret <= 0) {
if(ret == MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY)
return 0;
*curlcode = (ret == MBEDTLS_ERR_SSL_WANT_READ) ?
CURLE_AGAIN : CURLE_RECV_ERROR;
return -1;
}
len = ret;
return len;
}
static void mbedtls_session_free(void *ptr)
{
mbedtls_ssl_session_free(ptr);
free(ptr);
}
static size_t mbedtls_version(char *buffer, size_t size)
{
#ifdef MBEDTLS_VERSION_C
/* if mbedtls_version_get_number() is available it is better */
unsigned int version = mbedtls_version_get_number();
return msnprintf(buffer, size, "mbedTLS/%u.%u.%u", version>>24,
(version>>16)&0xff, (version>>8)&0xff);
#else
return msnprintf(buffer, size, "mbedTLS/%s", MBEDTLS_VERSION_STRING);
#endif
}
static CURLcode mbedtls_random(struct Curl_easy *data,
unsigned char *entropy, size_t length)
{
#if defined(MBEDTLS_CTR_DRBG_C)
int ret = -1;
char errorbuf[128];
mbedtls_entropy_context ctr_entropy;
mbedtls_ctr_drbg_context ctr_drbg;
mbedtls_entropy_init(&ctr_entropy);
mbedtls_ctr_drbg_init(&ctr_drbg);
ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func,
&ctr_entropy, NULL, 0);
if(ret) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "mbedtls_ctr_drbg_seed returned (-0x%04X) %s",
-ret, errorbuf);
}
else {
ret = mbedtls_ctr_drbg_random(&ctr_drbg, entropy, length);
if(ret) {
mbedtls_strerror(ret, errorbuf, sizeof(errorbuf));
failf(data, "mbedtls_ctr_drbg_random returned (-0x%04X) %s",
-ret, errorbuf);
}
}
mbedtls_ctr_drbg_free(&ctr_drbg);
mbedtls_entropy_free(&ctr_entropy);
return ret == 0 ? CURLE_OK : CURLE_FAILED_INIT;
#elif defined(MBEDTLS_HAVEGE_C)
mbedtls_havege_state hs;
mbedtls_havege_init(&hs);
mbedtls_havege_random(&hs, entropy, length);
mbedtls_havege_free(&hs);
return CURLE_OK;
#else
return CURLE_NOT_BUILT_IN;
#endif
}
static CURLcode
mbed_connect_common(struct Curl_cfilter *cf, struct Curl_easy *data,
bool nonblocking,
bool *done)
{
CURLcode retcode;
struct ssl_connect_data *connssl = cf->ctx;
curl_socket_t sockfd = Curl_conn_cf_get_socket(cf, data);
timediff_t timeout_ms;
int what;
/* check if the connection has already been established */
if(ssl_connection_complete == connssl->state) {
*done = TRUE;
return CURLE_OK;
}
if(ssl_connect_1 == connssl->connecting_state) {
/* Find out how much more time we're allowed */
timeout_ms = Curl_timeleft(data, NULL, TRUE);
if(timeout_ms < 0) {
/* no need to continue if time already is up */
failf(data, "SSL connection timeout");
return CURLE_OPERATION_TIMEDOUT;
}
retcode = mbed_connect_step1(cf, data);
if(retcode)
return retcode;
}
while(ssl_connect_2 == connssl->connecting_state ||
ssl_connect_2_reading == connssl->connecting_state ||
ssl_connect_2_writing == connssl->connecting_state) {
/* check allowed time left */
timeout_ms = Curl_timeleft(data, NULL, TRUE);
if(timeout_ms < 0) {
/* no need to continue if time already is up */
failf(data, "SSL connection timeout");
return CURLE_OPERATION_TIMEDOUT;
}
/* if ssl is expecting something, check if it's available. */
if(connssl->connecting_state == ssl_connect_2_reading
|| connssl->connecting_state == ssl_connect_2_writing) {
curl_socket_t writefd = ssl_connect_2_writing ==
connssl->connecting_state?sockfd:CURL_SOCKET_BAD;
curl_socket_t readfd = ssl_connect_2_reading ==
connssl->connecting_state?sockfd:CURL_SOCKET_BAD;
what = Curl_socket_check(readfd, CURL_SOCKET_BAD, writefd,
nonblocking ? 0 : timeout_ms);
if(what < 0) {
/* fatal error */
failf(data, "select/poll on SSL socket, errno: %d", SOCKERRNO);
return CURLE_SSL_CONNECT_ERROR;
}
else if(0 == what) {
if(nonblocking) {
*done = FALSE;
return CURLE_OK;
}
else {
/* timeout */
failf(data, "SSL connection timeout");
return CURLE_OPERATION_TIMEDOUT;
}
}
/* socket is readable or writable */
}
/* Run transaction, and return to the caller if it failed or if
* this connection is part of a multi handle and this loop would
* execute again. This permits the owner of a multi handle to
* abort a connection attempt before step2 has completed while
* ensuring that a client using select() or epoll() will always
* have a valid fdset to wait on.
*/
retcode = mbed_connect_step2(cf, data);
if(retcode || (nonblocking &&
(ssl_connect_2 == connssl->connecting_state ||
ssl_connect_2_reading == connssl->connecting_state ||
ssl_connect_2_writing == connssl->connecting_state)))
return retcode;
} /* repeat step2 until all transactions are done. */
if(ssl_connect_3 == connssl->connecting_state) {
retcode = mbed_connect_step3(cf, data);
if(retcode)
return retcode;
}
if(ssl_connect_done == connssl->connecting_state) {
connssl->state = ssl_connection_complete;
*done = TRUE;
}
else
*done = FALSE;
/* Reset our connect state machine */
connssl->connecting_state = ssl_connect_1;
return CURLE_OK;
}
static CURLcode mbedtls_connect_nonblocking(struct Curl_cfilter *cf,
struct Curl_easy *data,
bool *done)
{
return mbed_connect_common(cf, data, TRUE, done);
}
static CURLcode mbedtls_connect(struct Curl_cfilter *cf,
struct Curl_easy *data)
{
CURLcode retcode;
bool done = FALSE;
retcode = mbed_connect_common(cf, data, FALSE, &done);
if(retcode)
return retcode;
DEBUGASSERT(done);
return CURLE_OK;
}
/*
* return 0 error initializing SSL
* return 1 SSL initialized successfully
*/
static int mbedtls_init(void)
{
return Curl_mbedtlsthreadlock_thread_setup();
}
static void mbedtls_cleanup(void)
{
(void)Curl_mbedtlsthreadlock_thread_cleanup();
}
static bool mbedtls_data_pending(struct Curl_cfilter *cf,
const struct Curl_easy *data)
{
struct ssl_connect_data *ctx = cf->ctx;
struct mbed_ssl_backend_data *backend;
(void)data;
DEBUGASSERT(ctx && ctx->backend);
backend = (struct mbed_ssl_backend_data *)ctx->backend;
return mbedtls_ssl_get_bytes_avail(&backend->ssl) != 0;
}
static CURLcode mbedtls_sha256sum(const unsigned char *input,
size_t inputlen,
unsigned char *sha256sum,
size_t sha256len UNUSED_PARAM)
{
/* TODO: explain this for different mbedtls 2.x vs 3 version */
(void)sha256len;
#if MBEDTLS_VERSION_NUMBER < 0x02070000
mbedtls_sha256(input, inputlen, sha256sum, 0);
#else
/* returns 0 on success, otherwise failure */
#if MBEDTLS_VERSION_NUMBER >= 0x03000000
if(mbedtls_sha256(input, inputlen, sha256sum, 0) != 0)
#else
if(mbedtls_sha256_ret(input, inputlen, sha256sum, 0) != 0)
#endif
return CURLE_BAD_FUNCTION_ARGUMENT;
#endif
return CURLE_OK;
}
static void *mbedtls_get_internals(struct ssl_connect_data *connssl,
CURLINFO info UNUSED_PARAM)
{
struct mbed_ssl_backend_data *backend =
(struct mbed_ssl_backend_data *)connssl->backend;
(void)info;
DEBUGASSERT(backend);
return &backend->ssl;
}
const struct Curl_ssl Curl_ssl_mbedtls = {
{ CURLSSLBACKEND_MBEDTLS, "mbedtls" }, /* info */
SSLSUPP_CA_PATH |
SSLSUPP_CAINFO_BLOB |
SSLSUPP_PINNEDPUBKEY |
SSLSUPP_SSL_CTX |
SSLSUPP_HTTPS_PROXY,
sizeof(struct mbed_ssl_backend_data),
mbedtls_init, /* init */
mbedtls_cleanup, /* cleanup */
mbedtls_version, /* version */
Curl_none_check_cxn, /* check_cxn */
Curl_none_shutdown, /* shutdown */
mbedtls_data_pending, /* data_pending */
mbedtls_random, /* random */
Curl_none_cert_status_request, /* cert_status_request */
mbedtls_connect, /* connect */
mbedtls_connect_nonblocking, /* connect_nonblocking */
Curl_ssl_get_select_socks, /* getsock */
mbedtls_get_internals, /* get_internals */
mbedtls_close, /* close_one */
mbedtls_close_all, /* close_all */
mbedtls_session_free, /* session_free */
Curl_none_set_engine, /* set_engine */
Curl_none_set_engine_default, /* set_engine_default */
Curl_none_engines_list, /* engines_list */
Curl_none_false_start, /* false_start */
mbedtls_sha256sum, /* sha256sum */
NULL, /* associate_connection */
NULL, /* disassociate_connection */
NULL, /* free_multi_ssl_backend_data */
mbed_recv, /* recv decrypted data */
mbed_send, /* send data to encrypt */
};
#endif /* USE_MBEDTLS */