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review.trustedfirmware.org / mirror / mbed-tls / refs/heads/mbedtls-2.28 / . / library / ssl_cli.c
blob: 2854e00fcb118a7f74026540e230e1847da7c0cc [file] [log] [blame]
/*
* SSLv3/TLSv1 client-side functions
*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
*/
#include "common.h"
#if defined(MBEDTLS_SSL_CLI_C)
#include "mbedtls/platform.h"
#include "mbedtls/ssl.h"
#include "mbedtls/ssl_internal.h"
#include "mbedtls/debug.h"
#include "mbedtls/error.h"
#include "mbedtls/constant_time.h"
#if defined(MBEDTLS_USE_PSA_CRYPTO)
#include "mbedtls/psa_util.h"
#include "psa/crypto.h"
#endif /* MBEDTLS_USE_PSA_CRYPTO */
#include <string.h>
#include <stdint.h>
#if defined(MBEDTLS_HAVE_TIME)
#include "mbedtls/platform_time.h"
#endif
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
#include "mbedtls/platform_util.h"
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_conf_has_static_psk(mbedtls_ssl_config const *conf)
{
if (conf->psk_identity == NULL ||
conf->psk_identity_len == 0) {
return 0;
}
if (conf->psk != NULL && conf->psk_len != 0) {
return 1;
}
#if defined(MBEDTLS_USE_PSA_CRYPTO)
if (!mbedtls_svc_key_id_is_null(conf->psk_opaque)) {
return 1;
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
return 0;
}
#if defined(MBEDTLS_USE_PSA_CRYPTO)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_conf_has_static_raw_psk(mbedtls_ssl_config const *conf)
{
if (conf->psk_identity == NULL ||
conf->psk_identity_len == 0) {
return 0;
}
if (conf->psk != NULL && conf->psk_len != 0) {
return 1;
}
return 0;
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_hostname_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
const char *hostname = mbedtls_ssl_get_hostname_pointer(ssl);
size_t hostname_len;
*olen = 0;
if (hostname == NULL) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, adding server name extension: %s",
hostname));
hostname_len = strlen(hostname);
MBEDTLS_SSL_CHK_BUF_PTR(p, end, hostname_len + 9);
/*
* Sect. 3, RFC 6066 (TLS Extensions Definitions)
*
* In order to provide any of the server names, clients MAY include an
* extension of type "server_name" in the (extended) client hello. The
* "extension_data" field of this extension SHALL contain
* "ServerNameList" where:
*
* struct {
* NameType name_type;
* select (name_type) {
* case host_name: HostName;
* } name;
* } ServerName;
*
* enum {
* host_name(0), (255)
* } NameType;
*
* opaque HostName<1..2^16-1>;
*
* struct {
* ServerName server_name_list<1..2^16-1>
* } ServerNameList;
*
*/
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_SERVERNAME, p, 0);
p += 2;
MBEDTLS_PUT_UINT16_BE(hostname_len + 5, p, 0);
p += 2;
MBEDTLS_PUT_UINT16_BE(hostname_len + 3, p, 0);
p += 2;
*p++ = MBEDTLS_BYTE_0(MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME);
MBEDTLS_PUT_UINT16_BE(hostname_len, p, 0);
p += 2;
memcpy(p, hostname, hostname_len);
*olen = hostname_len + 9;
return 0;
}
#endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
#if defined(MBEDTLS_SSL_RENEGOTIATION)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_renegotiation_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
*olen = 0;
/* We're always including a TLS_EMPTY_RENEGOTIATION_INFO_SCSV in the
* initial ClientHello, in which case also adding the renegotiation
* info extension is NOT RECOMMENDED as per RFC 5746 Section 3.4. */
if (ssl->renego_status != MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, adding renegotiation extension"));
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 5 + ssl->verify_data_len);
/*
* Secure renegotiation
*/
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_RENEGOTIATION_INFO, p, 0);
p += 2;
*p++ = 0x00;
*p++ = MBEDTLS_BYTE_0(ssl->verify_data_len + 1);
*p++ = MBEDTLS_BYTE_0(ssl->verify_data_len);
memcpy(p, ssl->own_verify_data, ssl->verify_data_len);
*olen = 5 + ssl->verify_data_len;
return 0;
}
#endif /* MBEDTLS_SSL_RENEGOTIATION */
/*
* Only if we handle at least one key exchange that needs signatures.
*/
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_signature_algorithms_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
size_t sig_alg_len = 0;
const int *md;
#if defined(MBEDTLS_RSA_C) || defined(MBEDTLS_ECDSA_C)
unsigned char *sig_alg_list = buf + 6;
#endif
*olen = 0;
if (ssl->conf->max_minor_ver != MBEDTLS_SSL_MINOR_VERSION_3) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, adding signature_algorithms extension"));
if (ssl->conf->sig_hashes == NULL) {
return MBEDTLS_ERR_SSL_BAD_CONFIG;
}
for (md = ssl->conf->sig_hashes; *md != MBEDTLS_MD_NONE; md++) {
#if defined(MBEDTLS_ECDSA_C)
sig_alg_len += 2;
#endif
#if defined(MBEDTLS_RSA_C)
sig_alg_len += 2;
#endif
if (sig_alg_len > MBEDTLS_SSL_MAX_SIG_HASH_ALG_LIST_LEN) {
MBEDTLS_SSL_DEBUG_MSG(3,
("length in bytes of sig-hash-alg extension too big"));
return MBEDTLS_ERR_SSL_BAD_CONFIG;
}
}
/* Empty signature algorithms list, this is a configuration error. */
if (sig_alg_len == 0) {
return MBEDTLS_ERR_SSL_BAD_CONFIG;
}
MBEDTLS_SSL_CHK_BUF_PTR(p, end, sig_alg_len + 6);
/*
* Prepare signature_algorithms extension (TLS 1.2)
*/
sig_alg_len = 0;
for (md = ssl->conf->sig_hashes; *md != MBEDTLS_MD_NONE; md++) {
#if defined(MBEDTLS_ECDSA_C)
sig_alg_list[sig_alg_len++] = mbedtls_ssl_hash_from_md_alg(*md);
sig_alg_list[sig_alg_len++] = MBEDTLS_SSL_SIG_ECDSA;
#endif
#if defined(MBEDTLS_RSA_C)
sig_alg_list[sig_alg_len++] = mbedtls_ssl_hash_from_md_alg(*md);
sig_alg_list[sig_alg_len++] = MBEDTLS_SSL_SIG_RSA;
#endif
}
/*
* enum {
* none(0), md5(1), sha1(2), sha224(3), sha256(4), sha384(5),
* sha512(6), (255)
* } HashAlgorithm;
*
* enum { anonymous(0), rsa(1), dsa(2), ecdsa(3), (255) }
* SignatureAlgorithm;
*
* struct {
* HashAlgorithm hash;
* SignatureAlgorithm signature;
* } SignatureAndHashAlgorithm;
*
* SignatureAndHashAlgorithm
* supported_signature_algorithms<2..2^16-2>;
*/
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_SIG_ALG, p, 0);
p += 2;
MBEDTLS_PUT_UINT16_BE(sig_alg_len + 2, p, 0);
p += 2;
MBEDTLS_PUT_UINT16_BE(sig_alg_len, p, 0);
p += 2;
*olen = 6 + sig_alg_len;
return 0;
}
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 &&
MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_supported_elliptic_curves_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
unsigned char *elliptic_curve_list = p + 6;
size_t elliptic_curve_len = 0;
const mbedtls_ecp_curve_info *info;
const mbedtls_ecp_group_id *grp_id;
*olen = 0;
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, adding supported_elliptic_curves extension"));
if (ssl->conf->curve_list == NULL) {
return MBEDTLS_ERR_SSL_BAD_CONFIG;
}
for (grp_id = ssl->conf->curve_list;
*grp_id != MBEDTLS_ECP_DP_NONE;
grp_id++) {
info = mbedtls_ecp_curve_info_from_grp_id(*grp_id);
if (info == NULL) {
MBEDTLS_SSL_DEBUG_MSG(1,
("invalid curve in ssl configuration"));
return MBEDTLS_ERR_SSL_BAD_CONFIG;
}
elliptic_curve_len += 2;
if (elliptic_curve_len > MBEDTLS_SSL_MAX_CURVE_LIST_LEN) {
MBEDTLS_SSL_DEBUG_MSG(3,
("malformed supported_elliptic_curves extension in config"));
return MBEDTLS_ERR_SSL_BAD_CONFIG;
}
}
/* Empty elliptic curve list, this is a configuration error. */
if (elliptic_curve_len == 0) {
return MBEDTLS_ERR_SSL_BAD_CONFIG;
}
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 6 + elliptic_curve_len);
elliptic_curve_len = 0;
for (grp_id = ssl->conf->curve_list;
*grp_id != MBEDTLS_ECP_DP_NONE;
grp_id++) {
info = mbedtls_ecp_curve_info_from_grp_id(*grp_id);
elliptic_curve_list[elliptic_curve_len++] = MBEDTLS_BYTE_1(info->tls_id);
elliptic_curve_list[elliptic_curve_len++] = MBEDTLS_BYTE_0(info->tls_id);
}
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_SUPPORTED_ELLIPTIC_CURVES, p, 0);
p += 2;
MBEDTLS_PUT_UINT16_BE(elliptic_curve_len + 2, p, 0);
p += 2;
MBEDTLS_PUT_UINT16_BE(elliptic_curve_len, p, 0);
p += 2;
*olen = 6 + elliptic_curve_len;
return 0;
}
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_supported_point_formats_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
(void) ssl; /* ssl used for debugging only */
*olen = 0;
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, adding supported_point_formats extension"));
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 6);
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS, p, 0);
p += 2;
*p++ = 0x00;
*p++ = 2;
*p++ = 1;
*p++ = MBEDTLS_ECP_PF_UNCOMPRESSED;
*olen = 6;
return 0;
}
#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C ||
MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_ecjpake_kkpp_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char *p = buf;
size_t kkpp_len;
*olen = 0;
/* Skip costly extension if we can't use EC J-PAKE anyway */
if (mbedtls_ecjpake_check(&ssl->handshake->ecjpake_ctx) != 0) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, adding ecjpake_kkpp extension"));
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 4);
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_ECJPAKE_KKPP, p, 0);
p += 2;
/*
* We may need to send ClientHello multiple times for Hello verification.
* We don't want to compute fresh values every time (both for performance
* and consistency reasons), so cache the extension content.
*/
if (ssl->handshake->ecjpake_cache == NULL ||
ssl->handshake->ecjpake_cache_len == 0) {
MBEDTLS_SSL_DEBUG_MSG(3, ("generating new ecjpake parameters"));
ret = mbedtls_ecjpake_write_round_one(&ssl->handshake->ecjpake_ctx,
p + 2, end - p - 2, &kkpp_len,
ssl->conf->f_rng, ssl->conf->p_rng);
if (ret != 0) {
MBEDTLS_SSL_DEBUG_RET(1,
"mbedtls_ecjpake_write_round_one", ret);
return ret;
}
ssl->handshake->ecjpake_cache = mbedtls_calloc(1, kkpp_len);
if (ssl->handshake->ecjpake_cache == NULL) {
MBEDTLS_SSL_DEBUG_MSG(1, ("allocation failed"));
return MBEDTLS_ERR_SSL_ALLOC_FAILED;
}
memcpy(ssl->handshake->ecjpake_cache, p + 2, kkpp_len);
ssl->handshake->ecjpake_cache_len = kkpp_len;
} else {
MBEDTLS_SSL_DEBUG_MSG(3, ("re-using cached ecjpake parameters"));
kkpp_len = ssl->handshake->ecjpake_cache_len;
MBEDTLS_SSL_CHK_BUF_PTR(p + 2, end, kkpp_len);
memcpy(p + 2, ssl->handshake->ecjpake_cache, kkpp_len);
}
MBEDTLS_PUT_UINT16_BE(kkpp_len, p, 0);
p += 2;
*olen = kkpp_len + 4;
return 0;
}
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_cid_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
size_t ext_len;
/*
* Quoting draft-ietf-tls-dtls-connection-id-05
* https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05
*
* struct {
* opaque cid<0..2^8-1>;
* } ConnectionId;
*/
*olen = 0;
if (ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ||
ssl->negotiate_cid == MBEDTLS_SSL_CID_DISABLED) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, adding CID extension"));
/* ssl->own_cid_len is at most MBEDTLS_SSL_CID_IN_LEN_MAX
* which is at most 255, so the increment cannot overflow. */
MBEDTLS_SSL_CHK_BUF_PTR(p, end, (unsigned) (ssl->own_cid_len + 5));
/* Add extension ID + size */
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_CID, p, 0);
p += 2;
ext_len = (size_t) ssl->own_cid_len + 1;
MBEDTLS_PUT_UINT16_BE(ext_len, p, 0);
p += 2;
*p++ = (uint8_t) ssl->own_cid_len;
memcpy(p, ssl->own_cid, ssl->own_cid_len);
*olen = ssl->own_cid_len + 5;
return 0;
}
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_max_fragment_length_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
*olen = 0;
if (ssl->conf->mfl_code == MBEDTLS_SSL_MAX_FRAG_LEN_NONE) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, adding max_fragment_length extension"));
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 5);
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH, p, 0);
p += 2;
*p++ = 0x00;
*p++ = 1;
*p++ = ssl->conf->mfl_code;
*olen = 5;
return 0;
}
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_truncated_hmac_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
*olen = 0;
if (ssl->conf->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_DISABLED) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, adding truncated_hmac extension"));
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 4);
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_TRUNCATED_HMAC, p, 0);
p += 2;
*p++ = 0x00;
*p++ = 0x00;
*olen = 4;
return 0;
}
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_encrypt_then_mac_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
*olen = 0;
if (ssl->conf->encrypt_then_mac == MBEDTLS_SSL_ETM_DISABLED ||
ssl->conf->max_minor_ver == MBEDTLS_SSL_MINOR_VERSION_0) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, adding encrypt_then_mac extension"));
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 4);
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC, p, 0);
p += 2;
*p++ = 0x00;
*p++ = 0x00;
*olen = 4;
return 0;
}
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_extended_ms_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
*olen = 0;
if (ssl->conf->extended_ms == MBEDTLS_SSL_EXTENDED_MS_DISABLED ||
ssl->conf->max_minor_ver == MBEDTLS_SSL_MINOR_VERSION_0) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, adding extended_master_secret extension"));
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 4);
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET, p, 0);
p += 2;
*p++ = 0x00;
*p++ = 0x00;
*olen = 4;
return 0;
}
#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_session_ticket_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
size_t tlen = ssl->session_negotiate->ticket_len;
*olen = 0;
if (ssl->conf->session_tickets == MBEDTLS_SSL_SESSION_TICKETS_DISABLED) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, adding session ticket extension"));
/* The addition is safe here since the ticket length is 16 bit. */
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 4 + tlen);
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_SESSION_TICKET, p, 0);
p += 2;
MBEDTLS_PUT_UINT16_BE(tlen, p, 0);
p += 2;
*olen = 4;
if (ssl->session_negotiate->ticket == NULL || tlen == 0) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("sending session ticket of length %" MBEDTLS_PRINTF_SIZET, tlen));
memcpy(p, ssl->session_negotiate->ticket, tlen);
*olen += tlen;
return 0;
}
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
#if defined(MBEDTLS_SSL_ALPN)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_alpn_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
size_t alpnlen = 0;
const char **cur;
*olen = 0;
if (ssl->conf->alpn_list == NULL) {
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, adding alpn extension"));
for (cur = ssl->conf->alpn_list; *cur != NULL; cur++) {
alpnlen += strlen(*cur) + 1;
}
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 6 + alpnlen);
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_ALPN, p, 0);
p += 2;
/*
* opaque ProtocolName<1..2^8-1>;
*
* struct {
* ProtocolName protocol_name_list<2..2^16-1>
* } ProtocolNameList;
*/
/* Skip writing extension and list length for now */
p += 4;
for (cur = ssl->conf->alpn_list; *cur != NULL; cur++) {
/*
* mbedtls_ssl_conf_set_alpn_protocols() checked that the length of
* protocol names is less than 255.
*/
*p = (unsigned char) strlen(*cur);
memcpy(p + 1, *cur, *p);
p += 1 + *p;
}
*olen = p - buf;
/* List length = olen - 2 (ext_type) - 2 (ext_len) - 2 (list_len) */
MBEDTLS_PUT_UINT16_BE(*olen - 6, buf, 4);
/* Extension length = olen - 2 (ext_type) - 2 (ext_len) */
MBEDTLS_PUT_UINT16_BE(*olen - 4, buf, 2);
return 0;
}
#endif /* MBEDTLS_SSL_ALPN */
#if defined(MBEDTLS_SSL_DTLS_SRTP)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_use_srtp_ext(mbedtls_ssl_context *ssl,
unsigned char *buf,
const unsigned char *end,
size_t *olen)
{
unsigned char *p = buf;
size_t protection_profiles_index = 0, ext_len = 0;
uint16_t mki_len = 0, profile_value = 0;
*olen = 0;
if ((ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM) ||
(ssl->conf->dtls_srtp_profile_list == NULL) ||
(ssl->conf->dtls_srtp_profile_list_len == 0)) {
return 0;
}
/* RFC 5764 section 4.1.1
* uint8 SRTPProtectionProfile[2];
*
* struct {
* SRTPProtectionProfiles SRTPProtectionProfiles;
* opaque srtp_mki<0..255>;
* } UseSRTPData;
* SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1>;
*/
if (ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED) {
mki_len = ssl->dtls_srtp_info.mki_len;
}
/* Extension length = 2 bytes for profiles length,
* ssl->conf->dtls_srtp_profile_list_len * 2 (each profile is 2 bytes length ),
* 1 byte for srtp_mki vector length and the mki_len value
*/
ext_len = 2 + 2 * (ssl->conf->dtls_srtp_profile_list_len) + 1 + mki_len;
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, adding use_srtp extension"));
/* Check there is room in the buffer for the extension + 4 bytes
* - the extension tag (2 bytes)
* - the extension length (2 bytes)
*/
MBEDTLS_SSL_CHK_BUF_PTR(p, end, ext_len + 4);
MBEDTLS_PUT_UINT16_BE(MBEDTLS_TLS_EXT_USE_SRTP, p, 0);
p += 2;
MBEDTLS_PUT_UINT16_BE(ext_len, p, 0);
p += 2;
/* protection profile length: 2*(ssl->conf->dtls_srtp_profile_list_len) */
/* micro-optimization:
* the list size is limited to MBEDTLS_TLS_SRTP_MAX_PROFILE_LIST_LENGTH
* which is lower than 127, so the upper byte of the length is always 0
* For the documentation, the more generic code is left in comments
* *p++ = (unsigned char)( ( ( 2 * ssl->conf->dtls_srtp_profile_list_len )
* >> 8 ) & 0xFF );
*/
*p++ = 0;
*p++ = MBEDTLS_BYTE_0(2 * ssl->conf->dtls_srtp_profile_list_len);
for (protection_profiles_index = 0;
protection_profiles_index < ssl->conf->dtls_srtp_profile_list_len;
protection_profiles_index++) {
profile_value = mbedtls_ssl_check_srtp_profile_value
(ssl->conf->dtls_srtp_profile_list[protection_profiles_index]);
if (profile_value != MBEDTLS_TLS_SRTP_UNSET) {
MBEDTLS_SSL_DEBUG_MSG(3, ("ssl_write_use_srtp_ext, add profile: %04x",
profile_value));
MBEDTLS_PUT_UINT16_BE(profile_value, p, 0);
p += 2;
} else {
/*
* Note: we shall never arrive here as protection profiles
* is checked by mbedtls_ssl_conf_dtls_srtp_protection_profiles function
*/
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, "
"illegal DTLS-SRTP protection profile %d",
ssl->conf->dtls_srtp_profile_list[protection_profiles_index]
));
return MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
}
}
*p++ = mki_len & 0xFF;
if (mki_len != 0) {
memcpy(p, ssl->dtls_srtp_info.mki_value, mki_len);
/*
* Increment p to point to the current position.
*/
p += mki_len;
MBEDTLS_SSL_DEBUG_BUF(3, "sending mki", ssl->dtls_srtp_info.mki_value,
ssl->dtls_srtp_info.mki_len);
}
/*
* total extension length: extension type (2 bytes)
* + extension length (2 bytes)
* + protection profile length (2 bytes)
* + 2 * number of protection profiles
* + srtp_mki vector length(1 byte)
* + mki value
*/
*olen = p - buf;
return 0;
}
#endif /* MBEDTLS_SSL_DTLS_SRTP */
/*
* Generate random bytes for ClientHello
*/
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_generate_random(mbedtls_ssl_context *ssl)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char *p = ssl->handshake->randbytes;
#if defined(MBEDTLS_HAVE_TIME)
mbedtls_time_t t;
#endif
/*
* When responding to a verify request, MUST reuse random (RFC 6347 4.2.1)
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->handshake->verify_cookie != NULL) {
return 0;
}
#endif
#if defined(MBEDTLS_HAVE_TIME)
t = mbedtls_time(NULL);
MBEDTLS_PUT_UINT32_BE(t, p, 0);
p += 4;
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, current time: %" MBEDTLS_PRINTF_LONGLONG,
(long long) t));
#else
if ((ret = ssl->conf->f_rng(ssl->conf->p_rng, p, 4)) != 0) {
return ret;
}
p += 4;
#endif /* MBEDTLS_HAVE_TIME */
if ((ret = ssl->conf->f_rng(ssl->conf->p_rng, p, 28)) != 0) {
return ret;
}
return 0;
}
/**
* \brief Validate cipher suite against config in SSL context.
*
* \param suite_info cipher suite to validate
* \param ssl SSL context
* \param min_minor_ver Minimal minor version to accept a cipher suite
* \param max_minor_ver Maximal minor version to accept a cipher suite
*
* \return 0 if valid, else 1
*/
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_validate_ciphersuite(
const mbedtls_ssl_ciphersuite_t *suite_info,
const mbedtls_ssl_context *ssl,
int min_minor_ver, int max_minor_ver)
{
(void) ssl;
if (suite_info == NULL) {
return 1;
}
if (suite_info->min_minor_ver > max_minor_ver ||
suite_info->max_minor_ver < min_minor_ver) {
return 1;
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
(suite_info->flags & MBEDTLS_CIPHERSUITE_NODTLS)) {
return 1;
}
#endif
#if defined(MBEDTLS_ARC4_C)
if (ssl->conf->arc4_disabled == MBEDTLS_SSL_ARC4_DISABLED &&
suite_info->cipher == MBEDTLS_CIPHER_ARC4_128) {
return 1;
}
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
if (suite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE &&
mbedtls_ecjpake_check(&ssl->handshake->ecjpake_ctx) != 0) {
return 1;
}
#endif
/* Don't suggest PSK-based ciphersuite if no PSK is available. */
#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
if (mbedtls_ssl_ciphersuite_uses_psk(suite_info) &&
ssl_conf_has_static_psk(ssl->conf) == 0) {
return 1;
}
#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
return 0;
}
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_client_hello(mbedtls_ssl_context *ssl)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t i, n, olen, ext_len = 0;
unsigned char *buf;
unsigned char *p, *q;
const unsigned char *end;
unsigned char offer_compress;
const int *ciphersuites;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info;
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
int uses_ec = 0;
#endif
MBEDTLS_SSL_DEBUG_MSG(2, ("=> write client hello"));
if (ssl->conf->f_rng == NULL) {
MBEDTLS_SSL_DEBUG_MSG(1, ("no RNG provided"));
return MBEDTLS_ERR_SSL_NO_RNG;
}
int renegotiating = 0;
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if (ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE) {
renegotiating = 1;
}
#endif
if (!renegotiating) {
ssl->major_ver = ssl->conf->min_major_ver;
ssl->minor_ver = ssl->conf->min_minor_ver;
}
if (ssl->conf->max_major_ver == 0) {
MBEDTLS_SSL_DEBUG_MSG(1,
(
"configured max major version is invalid, consider using mbedtls_ssl_config_defaults()"));
return MBEDTLS_ERR_SSL_BAD_INPUT_DATA;
}
buf = ssl->out_msg;
end = buf + MBEDTLS_SSL_OUT_CONTENT_LEN;
/*
* Check if there's enough space for the first part of the ClientHello
* consisting of the 38 bytes described below, the session identifier (at
* most 32 bytes) and its length (1 byte).
*
* Use static upper bounds instead of the actual values
* to allow the compiler to optimize this away.
*/
MBEDTLS_SSL_CHK_BUF_PTR(buf, end, 38 + 1 + 32);
/*
* The 38 first bytes of the ClientHello:
* 0 . 0 handshake type (written later)
* 1 . 3 handshake length (written later)
* 4 . 5 highest version supported
* 6 . 9 current UNIX time
* 10 . 37 random bytes
*
* The current UNIX time (4 bytes) and following 28 random bytes are written
* by ssl_generate_random() into ssl->handshake->randbytes buffer and then
* copied from there into the output buffer.
*/
p = buf + 4;
mbedtls_ssl_write_version(ssl->conf->max_major_ver,
ssl->conf->max_minor_ver,
ssl->conf->transport, p);
p += 2;
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, max version: [%d:%d]",
buf[4], buf[5]));
if ((ret = ssl_generate_random(ssl)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_generate_random", ret);
return ret;
}
memcpy(p, ssl->handshake->randbytes, 32);
MBEDTLS_SSL_DEBUG_BUF(3, "client hello, random bytes", p, 32);
p += 32;
/*
* 38 . 38 session id length
* 39 . 39+n session id
* 39+n . 39+n DTLS only: cookie length (1 byte)
* 40+n . .. DTLS only: cookie
* .. . .. ciphersuitelist length (2 bytes)
* .. . .. ciphersuitelist
* .. . .. compression methods length (1 byte)
* .. . .. compression methods
* .. . .. extensions length (2 bytes)
* .. . .. extensions
*/
n = ssl->session_negotiate->id_len;
if (n < 16 || n > 32 ||
#if defined(MBEDTLS_SSL_RENEGOTIATION)
ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE ||
#endif
ssl->handshake->resume == 0) {
n = 0;
}
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
/*
* RFC 5077 section 3.4: "When presenting a ticket, the client MAY
* generate and include a Session ID in the TLS ClientHello."
*/
if (!renegotiating) {
if (ssl->session_negotiate->ticket != NULL &&
ssl->session_negotiate->ticket_len != 0) {
ret = ssl->conf->f_rng(ssl->conf->p_rng,
ssl->session_negotiate->id, 32);
if (ret != 0) {
return ret;
}
ssl->session_negotiate->id_len = n = 32;
}
}
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
/*
* The first check of the output buffer size above (
* MBEDTLS_SSL_CHK_BUF_PTR( buf, end, 38 + 1 + 32 );)
* has checked that there is enough space in the output buffer for the
* session identifier length byte and the session identifier (n <= 32).
*/
*p++ = (unsigned char) n;
for (i = 0; i < n; i++) {
*p++ = ssl->session_negotiate->id[i];
}
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, session id len.: %" MBEDTLS_PRINTF_SIZET, n));
MBEDTLS_SSL_DEBUG_BUF(3, "client hello, session id", buf + 39, n);
/*
* With 'n' being the length of the session identifier
*
* 39+n . 39+n DTLS only: cookie length (1 byte)
* 40+n . .. DTLS only: cookie
* .. . .. ciphersuitelist length (2 bytes)
* .. . .. ciphersuitelist
* .. . .. compression methods length (1 byte)
* .. . .. compression methods
* .. . .. extensions length (2 bytes)
* .. . .. extensions
*/
/*
* DTLS cookie
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM) {
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 1);
if (ssl->handshake->verify_cookie == NULL) {
MBEDTLS_SSL_DEBUG_MSG(3, ("no verify cookie to send"));
*p++ = 0;
} else {
MBEDTLS_SSL_DEBUG_BUF(3, "client hello, cookie",
ssl->handshake->verify_cookie,
ssl->handshake->verify_cookie_len);
*p++ = ssl->handshake->verify_cookie_len;
MBEDTLS_SSL_CHK_BUF_PTR(p, end,
ssl->handshake->verify_cookie_len);
memcpy(p, ssl->handshake->verify_cookie,
ssl->handshake->verify_cookie_len);
p += ssl->handshake->verify_cookie_len;
}
}
#endif
/*
* Ciphersuite list
*/
ciphersuites = ssl->conf->ciphersuite_list[ssl->minor_ver];
/* Skip writing ciphersuite length for now */
n = 0;
q = p;
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 2);
p += 2;
for (i = 0; ciphersuites[i] != 0; i++) {
ciphersuite_info = mbedtls_ssl_ciphersuite_from_id(ciphersuites[i]);
if (ssl_validate_ciphersuite(ciphersuite_info, ssl,
ssl->conf->min_minor_ver,
ssl->conf->max_minor_ver) != 0) {
continue;
}
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, add ciphersuite: %#04x (%s)",
(unsigned int) ciphersuites[i], ciphersuite_info->name));
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
uses_ec |= mbedtls_ssl_ciphersuite_uses_ec(ciphersuite_info);
#endif
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 2);
n++;
MBEDTLS_PUT_UINT16_BE(ciphersuites[i], p, 0);
p += 2;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("client hello, got %" MBEDTLS_PRINTF_SIZET
" ciphersuites (excluding SCSVs)", n));
/*
* Add TLS_EMPTY_RENEGOTIATION_INFO_SCSV
*/
if (!renegotiating) {
MBEDTLS_SSL_DEBUG_MSG(3, ("adding EMPTY_RENEGOTIATION_INFO_SCSV"));
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 2);
MBEDTLS_PUT_UINT16_BE(MBEDTLS_SSL_EMPTY_RENEGOTIATION_INFO, p, 0);
p += 2;
n++;
}
/* Some versions of OpenSSL don't handle it correctly if not at end */
#if defined(MBEDTLS_SSL_FALLBACK_SCSV)
if (ssl->conf->fallback == MBEDTLS_SSL_IS_FALLBACK) {
MBEDTLS_SSL_DEBUG_MSG(3, ("adding FALLBACK_SCSV"));
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 2);
MBEDTLS_PUT_UINT16_BE(MBEDTLS_SSL_FALLBACK_SCSV_VALUE, p, 0);
p += 2;
n++;
}
#endif
*q++ = (unsigned char) (n >> 7);
*q++ = (unsigned char) (n << 1);
#if defined(MBEDTLS_ZLIB_SUPPORT)
offer_compress = 1;
#else
offer_compress = 0;
#endif
/*
* We don't support compression with DTLS right now: if many records come
* in the same datagram, uncompressing one could overwrite the next one.
* We don't want to add complexity for handling that case unless there is
* an actual need for it.
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM) {
offer_compress = 0;
}
#endif
if (offer_compress) {
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, compress len.: %d", 2));
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, compress alg.: %d %d",
MBEDTLS_SSL_COMPRESS_DEFLATE,
MBEDTLS_SSL_COMPRESS_NULL));
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 3);
*p++ = 2;
*p++ = MBEDTLS_SSL_COMPRESS_DEFLATE;
*p++ = MBEDTLS_SSL_COMPRESS_NULL;
} else {
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, compress len.: %d", 1));
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, compress alg.: %d",
MBEDTLS_SSL_COMPRESS_NULL));
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 2);
*p++ = 1;
*p++ = MBEDTLS_SSL_COMPRESS_NULL;
}
/* First write extensions, then the total length */
MBEDTLS_SSL_CHK_BUF_PTR(p, end, 2);
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
if ((ret = ssl_write_hostname_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_hostname_ext", ret);
return ret;
}
ext_len += olen;
#endif
/* Note that TLS_EMPTY_RENEGOTIATION_INFO_SCSV is always added
* even if MBEDTLS_SSL_RENEGOTIATION is not defined. */
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if ((ret = ssl_write_renegotiation_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_renegotiation_ext", ret);
return ret;
}
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
if ((ret = ssl_write_signature_algorithms_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_signature_algorithms_ext", ret);
return ret;
}
ext_len += olen;
#endif
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
if (uses_ec) {
if ((ret = ssl_write_supported_elliptic_curves_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_supported_elliptic_curves_ext", ret);
return ret;
}
ext_len += olen;
if ((ret = ssl_write_supported_point_formats_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_supported_point_formats_ext", ret);
return ret;
}
ext_len += olen;
}
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
if ((ret = ssl_write_ecjpake_kkpp_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_ecjpake_kkpp_ext", ret);
return ret;
}
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
if ((ret = ssl_write_cid_ext(ssl, p + 2 + ext_len, end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_cid_ext", ret);
return ret;
}
ext_len += olen;
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
if ((ret = ssl_write_max_fragment_length_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_max_fragment_length_ext", ret);
return ret;
}
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
if ((ret = ssl_write_truncated_hmac_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_truncated_hmac_ext", ret);
return ret;
}
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
if ((ret = ssl_write_encrypt_then_mac_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_encrypt_then_mac_ext", ret);
return ret;
}
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
if ((ret = ssl_write_extended_ms_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_extended_ms_ext", ret);
return ret;
}
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_ALPN)
if ((ret = ssl_write_alpn_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_alpn_ext", ret);
return ret;
}
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_DTLS_SRTP)
if ((ret = ssl_write_use_srtp_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_use_srtp_ext", ret);
return ret;
}
ext_len += olen;
#endif
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
if ((ret = ssl_write_session_ticket_ext(ssl, p + 2 + ext_len,
end, &olen)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_session_ticket_ext", ret);
return ret;
}
ext_len += olen;
#endif
/* olen unused if all extensions are disabled */
((void) olen);
MBEDTLS_SSL_DEBUG_MSG(3, ("client hello, total extension length: %" MBEDTLS_PRINTF_SIZET,
ext_len));
if (ext_len > 0) {
/* No need to check for space here, because the extension
* writing functions already took care of that. */
MBEDTLS_PUT_UINT16_BE(ext_len, p, 0);
p += 2 + ext_len;
}
ssl->out_msglen = p - buf;
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = MBEDTLS_SSL_HS_CLIENT_HELLO;
ssl->state++;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM) {
mbedtls_ssl_send_flight_completed(ssl);
}
#endif
if ((ret = mbedtls_ssl_write_handshake_msg(ssl)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_write_handshake_msg", ret);
return ret;
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
(ret = mbedtls_ssl_flight_transmit(ssl)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_flight_transmit", ret);
return ret;
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
MBEDTLS_SSL_DEBUG_MSG(2, ("<= write client hello"));
return 0;
}
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_renegotiation_info(mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len)
{
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if (ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE) {
/* Check verify-data in constant-time. The length OTOH is no secret */
if (len != 1 + ssl->verify_data_len * 2 ||
buf[0] != ssl->verify_data_len * 2 ||
mbedtls_ct_memcmp(buf + 1,
ssl->own_verify_data, ssl->verify_data_len) != 0 ||
mbedtls_ct_memcmp(buf + 1 + ssl->verify_data_len,
ssl->peer_verify_data, ssl->verify_data_len) != 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("non-matching renegotiation info"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
} else
#endif /* MBEDTLS_SSL_RENEGOTIATION */
{
if (len != 1 || buf[0] != 0x00) {
MBEDTLS_SSL_DEBUG_MSG(1,
("non-zero length renegotiation info"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
ssl->secure_renegotiation = MBEDTLS_SSL_SECURE_RENEGOTIATION;
}
return 0;
}
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_max_fragment_length_ext(mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len)
{
/*
* server should use the extension only if we did,
* and if so the server's value should match ours (and len is always 1)
*/
if (ssl->conf->mfl_code == MBEDTLS_SSL_MAX_FRAG_LEN_NONE ||
len != 1 ||
buf[0] != ssl->conf->mfl_code) {
MBEDTLS_SSL_DEBUG_MSG(1,
("non-matching max fragment length extension"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
return 0;
}
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_truncated_hmac_ext(mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len)
{
if (ssl->conf->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_DISABLED ||
len != 0) {
MBEDTLS_SSL_DEBUG_MSG(1,
("non-matching truncated HMAC extension"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
((void) buf);
ssl->session_negotiate->trunc_hmac = MBEDTLS_SSL_TRUNC_HMAC_ENABLED;
return 0;
}
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_cid_ext(mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len)
{
size_t peer_cid_len;
if ( /* CID extension only makes sense in DTLS */
ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM ||
/* The server must only send the CID extension if we have offered it. */
ssl->negotiate_cid == MBEDTLS_SSL_CID_DISABLED) {
MBEDTLS_SSL_DEBUG_MSG(1, ("CID extension unexpected"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
if (len == 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("CID extension invalid"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
peer_cid_len = *buf++;
len--;
if (peer_cid_len > MBEDTLS_SSL_CID_OUT_LEN_MAX) {
MBEDTLS_SSL_DEBUG_MSG(1, ("CID extension invalid"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
if (len != peer_cid_len) {
MBEDTLS_SSL_DEBUG_MSG(1, ("CID extension invalid"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
ssl->handshake->cid_in_use = MBEDTLS_SSL_CID_ENABLED;
ssl->handshake->peer_cid_len = (uint8_t) peer_cid_len;
memcpy(ssl->handshake->peer_cid, buf, peer_cid_len);
MBEDTLS_SSL_DEBUG_MSG(3, ("Use of CID extension negotiated"));
MBEDTLS_SSL_DEBUG_BUF(3, "Server CID", buf, peer_cid_len);
return 0;
}
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_encrypt_then_mac_ext(mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len)
{
if (ssl->conf->encrypt_then_mac == MBEDTLS_SSL_ETM_DISABLED ||
ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ||
len != 0) {
MBEDTLS_SSL_DEBUG_MSG(1,
("non-matching encrypt-then-MAC extension"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
((void) buf);
ssl->session_negotiate->encrypt_then_mac = MBEDTLS_SSL_ETM_ENABLED;
return 0;
}
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_extended_ms_ext(mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len)
{
if (ssl->conf->extended_ms == MBEDTLS_SSL_EXTENDED_MS_DISABLED ||
ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ||
len != 0) {
MBEDTLS_SSL_DEBUG_MSG(1,
("non-matching extended master secret extension"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
((void) buf);
ssl->handshake->extended_ms = MBEDTLS_SSL_EXTENDED_MS_ENABLED;
return 0;
}
#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_session_ticket_ext(mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len)
{
if (ssl->conf->session_tickets == MBEDTLS_SSL_SESSION_TICKETS_DISABLED ||
len != 0) {
MBEDTLS_SSL_DEBUG_MSG(1,
("non-matching session ticket extension"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
((void) buf);
ssl->handshake->new_session_ticket = 1;
return 0;
}
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_supported_point_formats_ext(mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len)
{
size_t list_size;
const unsigned char *p;
if (len == 0 || (size_t) (buf[0] + 1) != len) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello message"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
list_size = buf[0];
p = buf + 1;
while (list_size > 0) {
if (p[0] == MBEDTLS_ECP_PF_UNCOMPRESSED ||
p[0] == MBEDTLS_ECP_PF_COMPRESSED) {
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C)
ssl->handshake->ecdh_ctx.point_format = p[0];
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
ssl->handshake->ecjpake_ctx.point_format = p[0];
#endif
MBEDTLS_SSL_DEBUG_MSG(4, ("point format selected: %d", p[0]));
return 0;
}
list_size--;
p++;
}
MBEDTLS_SSL_DEBUG_MSG(1, ("no point format in common"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C ||
MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_ecjpake_kkpp(mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
if (ssl->handshake->ciphersuite_info->key_exchange !=
MBEDTLS_KEY_EXCHANGE_ECJPAKE) {
MBEDTLS_SSL_DEBUG_MSG(3, ("skip ecjpake kkpp extension"));
return 0;
}
/* If we got here, we no longer need our cached extension */
mbedtls_free(ssl->handshake->ecjpake_cache);
ssl->handshake->ecjpake_cache = NULL;
ssl->handshake->ecjpake_cache_len = 0;
if ((ret = mbedtls_ecjpake_read_round_one(&ssl->handshake->ecjpake_ctx,
buf, len)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ecjpake_read_round_one", ret);
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return ret;
}
return 0;
}
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_SSL_ALPN)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_alpn_ext(mbedtls_ssl_context *ssl,
const unsigned char *buf, size_t len)
{
size_t list_len, name_len;
const char **p;
/* If we didn't send it, the server shouldn't send it */
if (ssl->conf->alpn_list == NULL) {
MBEDTLS_SSL_DEBUG_MSG(1, ("non-matching ALPN extension"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNSUPPORTED_EXT);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
/*
* opaque ProtocolName<1..2^8-1>;
*
* struct {
* ProtocolName protocol_name_list<2..2^16-1>
* } ProtocolNameList;
*
* the "ProtocolNameList" MUST contain exactly one "ProtocolName"
*/
/* Min length is 2 (list_len) + 1 (name_len) + 1 (name) */
if (len < 4) {
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
list_len = (buf[0] << 8) | buf[1];
if (list_len != len - 2) {
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
name_len = buf[2];
if (name_len != list_len - 1) {
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
/* Check that the server chosen protocol was in our list and save it */
for (p = ssl->conf->alpn_list; *p != NULL; p++) {
if (name_len == strlen(*p) &&
memcmp(buf + 3, *p, name_len) == 0) {
ssl->alpn_chosen = *p;
return 0;
}
}
MBEDTLS_SSL_DEBUG_MSG(1, ("ALPN extension: no matching protocol"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
#endif /* MBEDTLS_SSL_ALPN */
#if defined(MBEDTLS_SSL_DTLS_SRTP)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_use_srtp_ext(mbedtls_ssl_context *ssl,
const unsigned char *buf,
size_t len)
{
mbedtls_ssl_srtp_profile server_protection = MBEDTLS_TLS_SRTP_UNSET;
size_t i, mki_len = 0;
uint16_t server_protection_profile_value = 0;
/* If use_srtp is not configured, just ignore the extension */
if ((ssl->conf->transport != MBEDTLS_SSL_TRANSPORT_DATAGRAM) ||
(ssl->conf->dtls_srtp_profile_list == NULL) ||
(ssl->conf->dtls_srtp_profile_list_len == 0)) {
return 0;
}
/* RFC 5764 section 4.1.1
* uint8 SRTPProtectionProfile[2];
*
* struct {
* SRTPProtectionProfiles SRTPProtectionProfiles;
* opaque srtp_mki<0..255>;
* } UseSRTPData;
* SRTPProtectionProfile SRTPProtectionProfiles<2..2^16-1>;
*
*/
if (ssl->conf->dtls_srtp_mki_support == MBEDTLS_SSL_DTLS_SRTP_MKI_SUPPORTED) {
mki_len = ssl->dtls_srtp_info.mki_len;
}
/*
* Length is 5 + optional mki_value : one protection profile length (2 bytes)
* + protection profile (2 bytes)
* + mki_len(1 byte)
* and optional srtp_mki
*/
if ((len < 5) || (len != (buf[4] + 5u))) {
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
/*
* get the server protection profile
*/
/*
* protection profile length must be 0x0002 as we must have only
* one protection profile in server Hello
*/
if ((buf[0] != 0) || (buf[1] != 2)) {
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
server_protection_profile_value = (buf[2] << 8) | buf[3];
server_protection = mbedtls_ssl_check_srtp_profile_value(
server_protection_profile_value);
if (server_protection != MBEDTLS_TLS_SRTP_UNSET) {
MBEDTLS_SSL_DEBUG_MSG(3, ("found srtp profile: %s",
mbedtls_ssl_get_srtp_profile_as_string(
server_protection)));
}
ssl->dtls_srtp_info.chosen_dtls_srtp_profile = MBEDTLS_TLS_SRTP_UNSET;
/*
* Check we have the server profile in our list
*/
for (i = 0; i < ssl->conf->dtls_srtp_profile_list_len; i++) {
if (server_protection == ssl->conf->dtls_srtp_profile_list[i]) {
ssl->dtls_srtp_info.chosen_dtls_srtp_profile = ssl->conf->dtls_srtp_profile_list[i];
MBEDTLS_SSL_DEBUG_MSG(3, ("selected srtp profile: %s",
mbedtls_ssl_get_srtp_profile_as_string(
server_protection)));
break;
}
}
/* If no match was found : server problem, it shall never answer with incompatible profile */
if (ssl->dtls_srtp_info.chosen_dtls_srtp_profile == MBEDTLS_TLS_SRTP_UNSET) {
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
/* If server does not use mki in its reply, make sure the client won't keep
* one as negotiated */
if (len == 5) {
ssl->dtls_srtp_info.mki_len = 0;
}
/*
* RFC5764:
* If the client detects a nonzero-length MKI in the server's response
* that is different than the one the client offered, then the client
* MUST abort the handshake and SHOULD send an invalid_parameter alert.
*/
if (len > 5 && (buf[4] != mki_len ||
(memcmp(ssl->dtls_srtp_info.mki_value, &buf[5], mki_len)))) {
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
#if defined(MBEDTLS_DEBUG_C)
if (len > 5) {
MBEDTLS_SSL_DEBUG_BUF(3, "received mki", ssl->dtls_srtp_info.mki_value,
ssl->dtls_srtp_info.mki_len);
}
#endif
return 0;
}
#endif /* MBEDTLS_SSL_DTLS_SRTP */
/*
* Parse HelloVerifyRequest. Only called after verifying the HS type.
*/
#if defined(MBEDTLS_SSL_PROTO_DTLS)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_hello_verify_request(mbedtls_ssl_context *ssl)
{
const unsigned char *p = ssl->in_msg + mbedtls_ssl_hs_hdr_len(ssl);
int major_ver, minor_ver;
unsigned char cookie_len;
MBEDTLS_SSL_DEBUG_MSG(2, ("=> parse hello verify request"));
/* Check that there is enough room for:
* - 2 bytes of version
* - 1 byte of cookie_len
*/
if (mbedtls_ssl_hs_hdr_len(ssl) + 3 > ssl->in_msglen) {
MBEDTLS_SSL_DEBUG_MSG(1,
("incoming HelloVerifyRequest message is too short"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
/*
* struct {
* ProtocolVersion server_version;
* opaque cookie<0..2^8-1>;
* } HelloVerifyRequest;
*/
MBEDTLS_SSL_DEBUG_BUF(3, "server version", p, 2);
mbedtls_ssl_read_version(&major_ver, &minor_ver, ssl->conf->transport, p);
p += 2;
/*
* Since the RFC is not clear on this point, accept DTLS 1.0 (TLS 1.1)
* even is lower than our min version.
*/
if (major_ver < MBEDTLS_SSL_MAJOR_VERSION_3 ||
minor_ver < MBEDTLS_SSL_MINOR_VERSION_2 ||
major_ver > ssl->conf->max_major_ver ||
minor_ver > ssl->conf->max_minor_ver) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server version"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION);
return MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION;
}
cookie_len = *p++;
if ((ssl->in_msg + ssl->in_msglen) - p < cookie_len) {
MBEDTLS_SSL_DEBUG_MSG(1,
("cookie length does not match incoming message size"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
MBEDTLS_SSL_DEBUG_BUF(3, "cookie", p, cookie_len);
mbedtls_free(ssl->handshake->verify_cookie);
ssl->handshake->verify_cookie = mbedtls_calloc(1, cookie_len);
if (ssl->handshake->verify_cookie == NULL) {
MBEDTLS_SSL_DEBUG_MSG(1, ("alloc failed (%d bytes)", cookie_len));
return MBEDTLS_ERR_SSL_ALLOC_FAILED;
}
memcpy(ssl->handshake->verify_cookie, p, cookie_len);
ssl->handshake->verify_cookie_len = cookie_len;
/* Start over at ClientHello */
ssl->state = MBEDTLS_SSL_CLIENT_HELLO;
mbedtls_ssl_reset_checksum(ssl);
mbedtls_ssl_recv_flight_completed(ssl);
MBEDTLS_SSL_DEBUG_MSG(2, ("<= parse hello verify request"));
return 0;
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
static int is_compression_bad(mbedtls_ssl_context *ssl, unsigned char comp)
{
int bad_comp = 0;
/* Suppress warnings in some configurations */
(void) ssl;
#if defined(MBEDTLS_ZLIB_SUPPORT)
/* See comments in ssl_write_client_hello() */
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
comp != MBEDTLS_SSL_COMPRESS_NULL) {
bad_comp = 1;
}
#endif
if (comp != MBEDTLS_SSL_COMPRESS_NULL &&
comp != MBEDTLS_SSL_COMPRESS_DEFLATE) {
bad_comp = 1;
}
#else /* MBEDTLS_ZLIB_SUPPORT */
if (comp != MBEDTLS_SSL_COMPRESS_NULL) {
bad_comp = 1;
}
#endif /* MBEDTLS_ZLIB_SUPPORT */
return bad_comp;
}
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_server_hello(mbedtls_ssl_context *ssl)
{
int ret, i;
size_t n;
size_t ext_len;
unsigned char *buf, *ext;
unsigned char comp;
#if defined(MBEDTLS_SSL_RENEGOTIATION)
int renegotiation_info_seen = 0;
#endif
int handshake_failure = 0;
const mbedtls_ssl_ciphersuite_t *suite_info;
MBEDTLS_SSL_DEBUG_MSG(2, ("=> parse server hello"));
if ((ret = mbedtls_ssl_read_record(ssl, 1)) != 0) {
/* No alert on a read error. */
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_read_record", ret);
return ret;
}
buf = ssl->in_msg;
if (ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE) {
#if defined(MBEDTLS_SSL_RENEGOTIATION)
if (ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS) {
ssl->renego_records_seen++;
if (ssl->conf->renego_max_records >= 0 &&
ssl->renego_records_seen > ssl->conf->renego_max_records) {
MBEDTLS_SSL_DEBUG_MSG(1,
("renegotiation requested, but not honored by server"));
return MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE;
}
MBEDTLS_SSL_DEBUG_MSG(1,
("non-handshake message during renegotiation"));
ssl->keep_current_message = 1;
return MBEDTLS_ERR_SSL_WAITING_SERVER_HELLO_RENEGO;
}
#endif /* MBEDTLS_SSL_RENEGOTIATION */
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE);
return MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE;
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM) {
if (buf[0] == MBEDTLS_SSL_HS_HELLO_VERIFY_REQUEST) {
MBEDTLS_SSL_DEBUG_MSG(2, ("received hello verify request"));
MBEDTLS_SSL_DEBUG_MSG(2, ("<= parse server hello"));
return ssl_parse_hello_verify_request(ssl);
} else {
/* We made it through the verification process */
mbedtls_free(ssl->handshake->verify_cookie);
ssl->handshake->verify_cookie = NULL;
ssl->handshake->verify_cookie_len = 0;
}
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
if (ssl->in_hslen < 38 + mbedtls_ssl_hs_hdr_len(ssl) ||
buf[0] != MBEDTLS_SSL_HS_SERVER_HELLO) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello message"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
/*
* 0 . 1 server_version
* 2 . 33 random (maybe including 4 bytes of Unix time)
* 34 . 34 session_id length = n
* 35 . 34+n session_id
* 35+n . 36+n cipher_suite
* 37+n . 37+n compression_method
*
* 38+n . 39+n extensions length (optional)
* 40+n . .. extensions
*/
buf += mbedtls_ssl_hs_hdr_len(ssl);
MBEDTLS_SSL_DEBUG_BUF(3, "server hello, version", buf + 0, 2);
mbedtls_ssl_read_version(&ssl->major_ver, &ssl->minor_ver,
ssl->conf->transport, buf + 0);
if (ssl->major_ver < ssl->conf->min_major_ver ||
ssl->minor_ver < ssl->conf->min_minor_ver ||
ssl->major_ver > ssl->conf->max_major_ver ||
ssl->minor_ver > ssl->conf->max_minor_ver) {
MBEDTLS_SSL_DEBUG_MSG(1,
(
"server version out of bounds - min: [%d:%d], server: [%d:%d], max: [%d:%d]",
ssl->conf->min_major_ver,
ssl->conf->min_minor_ver,
ssl->major_ver, ssl->minor_ver,
ssl->conf->max_major_ver,
ssl->conf->max_minor_ver));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION);
return MBEDTLS_ERR_SSL_BAD_HS_PROTOCOL_VERSION;
}
MBEDTLS_SSL_DEBUG_MSG(3, ("server hello, current time: %lu",
((unsigned long) buf[2] << 24) |
((unsigned long) buf[3] << 16) |
((unsigned long) buf[4] << 8) |
((unsigned long) buf[5])));
memcpy(ssl->handshake->randbytes + 32, buf + 2, 32);
n = buf[34];
MBEDTLS_SSL_DEBUG_BUF(3, "server hello, random bytes", buf + 2, 32);
if (n > 32) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello message"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
if (ssl->in_hslen > mbedtls_ssl_hs_hdr_len(ssl) + 39 + n) {
ext_len = ((buf[38 + n] << 8)
| (buf[39 + n]));
if ((ext_len > 0 && ext_len < 4) ||
ssl->in_hslen != mbedtls_ssl_hs_hdr_len(ssl) + 40 + n + ext_len) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
} else if (ssl->in_hslen == mbedtls_ssl_hs_hdr_len(ssl) + 38 + n) {
ext_len = 0;
} else {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello message"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
/* ciphersuite (used later) */
i = (buf[35 + n] << 8) | buf[36 + n];
/*
* Read and check compression
*/
comp = buf[37 + n];
if (is_compression_bad(ssl, comp)) {
MBEDTLS_SSL_DEBUG_MSG(1,
("server hello, bad compression: %d", comp));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
}
/*
* Initialize update checksum functions
*/
ssl->handshake->ciphersuite_info = mbedtls_ssl_ciphersuite_from_id(i);
if (ssl->handshake->ciphersuite_info == NULL) {
MBEDTLS_SSL_DEBUG_MSG(1,
("ciphersuite info for %04x not found", (unsigned int) i));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR);
return MBEDTLS_ERR_SSL_BAD_INPUT_DATA;
}
mbedtls_ssl_optimize_checksum(ssl, ssl->handshake->ciphersuite_info);
MBEDTLS_SSL_DEBUG_MSG(3, ("server hello, session id len.: %" MBEDTLS_PRINTF_SIZET, n));
MBEDTLS_SSL_DEBUG_BUF(3, "server hello, session id", buf + 35, n);
/*
* Check if the session can be resumed
*/
if (ssl->handshake->resume == 0 || n == 0 ||
#if defined(MBEDTLS_SSL_RENEGOTIATION)
ssl->renego_status != MBEDTLS_SSL_INITIAL_HANDSHAKE ||
#endif
ssl->session_negotiate->ciphersuite != i ||
ssl->session_negotiate->compression != comp ||
ssl->session_negotiate->id_len != n ||
memcmp(ssl->session_negotiate->id, buf + 35, n) != 0) {
ssl->state++;
ssl->handshake->resume = 0;
#if defined(MBEDTLS_HAVE_TIME)
ssl->session_negotiate->start = mbedtls_time(NULL);
#endif
ssl->session_negotiate->ciphersuite = i;
ssl->session_negotiate->compression = comp;
ssl->session_negotiate->id_len = n;
memcpy(ssl->session_negotiate->id, buf + 35, n);
} else {
ssl->state = MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC;
}
MBEDTLS_SSL_DEBUG_MSG(3, ("%s session has been resumed",
ssl->handshake->resume ? "a" : "no"));
MBEDTLS_SSL_DEBUG_MSG(3, ("server hello, chosen ciphersuite: %04x", (unsigned) i));
MBEDTLS_SSL_DEBUG_MSG(3, ("server hello, compress alg.: %d",
buf[37 + n]));
/*
* Perform cipher suite validation in same way as in ssl_write_client_hello.
*/
i = 0;
while (1) {
if (ssl->conf->ciphersuite_list[ssl->minor_ver][i] == 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
if (ssl->conf->ciphersuite_list[ssl->minor_ver][i++] ==
ssl->session_negotiate->ciphersuite) {
break;
}
}
suite_info = mbedtls_ssl_ciphersuite_from_id(
ssl->session_negotiate->ciphersuite);
if (ssl_validate_ciphersuite(suite_info, ssl, ssl->minor_ver,
ssl->minor_ver) != 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
MBEDTLS_SSL_DEBUG_MSG(3,
("server hello, chosen ciphersuite: %s", suite_info->name));
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (suite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA &&
ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3) {
ssl->handshake->ecrs_enabled = 1;
}
#endif
if (comp != MBEDTLS_SSL_COMPRESS_NULL
#if defined(MBEDTLS_ZLIB_SUPPORT)
&& comp != MBEDTLS_SSL_COMPRESS_DEFLATE
#endif
) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
ssl->session_negotiate->compression = comp;
ext = buf + 40 + n;
MBEDTLS_SSL_DEBUG_MSG(2,
("server hello, total extension length: %" MBEDTLS_PRINTF_SIZET,
ext_len));
while (ext_len) {
unsigned int ext_id = ((ext[0] << 8)
| (ext[1]));
unsigned int ext_size = ((ext[2] << 8)
| (ext[3]));
if (ext_size + 4 > ext_len) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello message"));
mbedtls_ssl_send_alert_message(
ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
switch (ext_id) {
case MBEDTLS_TLS_EXT_RENEGOTIATION_INFO:
MBEDTLS_SSL_DEBUG_MSG(3, ("found renegotiation extension"));
#if defined(MBEDTLS_SSL_RENEGOTIATION)
renegotiation_info_seen = 1;
#endif
if ((ret = ssl_parse_renegotiation_info(ssl, ext + 4,
ext_size)) != 0) {
return ret;
}
break;
#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
case MBEDTLS_TLS_EXT_MAX_FRAGMENT_LENGTH:
MBEDTLS_SSL_DEBUG_MSG(3,
("found max_fragment_length extension"));
if ((ret = ssl_parse_max_fragment_length_ext(ssl,
ext + 4, ext_size)) != 0) {
return ret;
}
break;
#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
case MBEDTLS_TLS_EXT_TRUNCATED_HMAC:
MBEDTLS_SSL_DEBUG_MSG(3, ("found truncated_hmac extension"));
if ((ret = ssl_parse_truncated_hmac_ext(ssl,
ext + 4, ext_size)) != 0) {
return ret;
}
break;
#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
case MBEDTLS_TLS_EXT_CID:
MBEDTLS_SSL_DEBUG_MSG(3, ("found CID extension"));
if ((ret = ssl_parse_cid_ext(ssl,
ext + 4,
ext_size)) != 0) {
return ret;
}
break;
#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
case MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC:
MBEDTLS_SSL_DEBUG_MSG(3, ("found encrypt_then_mac extension"));
if ((ret = ssl_parse_encrypt_then_mac_ext(ssl,
ext + 4, ext_size)) != 0) {
return ret;
}
break;
#endif /* MBEDTLS_SSL_ENCRYPT_THEN_MAC */
#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET)
case MBEDTLS_TLS_EXT_EXTENDED_MASTER_SECRET:
MBEDTLS_SSL_DEBUG_MSG(3,
("found extended_master_secret extension"));
if ((ret = ssl_parse_extended_ms_ext(ssl,
ext + 4, ext_size)) != 0) {
return ret;
}
break;
#endif /* MBEDTLS_SSL_EXTENDED_MASTER_SECRET */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
case MBEDTLS_TLS_EXT_SESSION_TICKET:
MBEDTLS_SSL_DEBUG_MSG(3, ("found session_ticket extension"));
if ((ret = ssl_parse_session_ticket_ext(ssl,
ext + 4, ext_size)) != 0) {
return ret;
}
break;
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
case MBEDTLS_TLS_EXT_SUPPORTED_POINT_FORMATS:
MBEDTLS_SSL_DEBUG_MSG(3,
("found supported_point_formats extension"));
if ((ret = ssl_parse_supported_point_formats_ext(ssl,
ext + 4, ext_size)) != 0) {
return ret;
}
break;
#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C ||
MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
case MBEDTLS_TLS_EXT_ECJPAKE_KKPP:
MBEDTLS_SSL_DEBUG_MSG(3, ("found ecjpake_kkpp extension"));
if ((ret = ssl_parse_ecjpake_kkpp(ssl,
ext + 4, ext_size)) != 0) {
return ret;
}
break;
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
#if defined(MBEDTLS_SSL_ALPN)
case MBEDTLS_TLS_EXT_ALPN:
MBEDTLS_SSL_DEBUG_MSG(3, ("found alpn extension"));
if ((ret = ssl_parse_alpn_ext(ssl, ext + 4, ext_size)) != 0) {
return ret;
}
break;
#endif /* MBEDTLS_SSL_ALPN */
#if defined(MBEDTLS_SSL_DTLS_SRTP)
case MBEDTLS_TLS_EXT_USE_SRTP:
MBEDTLS_SSL_DEBUG_MSG(3, ("found use_srtp extension"));
if ((ret = ssl_parse_use_srtp_ext(ssl, ext + 4, ext_size)) != 0) {
return ret;
}
break;
#endif /* MBEDTLS_SSL_DTLS_SRTP */
default:
MBEDTLS_SSL_DEBUG_MSG(3,
("unknown extension found: %u (ignoring)", ext_id));
}
ext_len -= 4 + ext_size;
ext += 4 + ext_size;
if (ext_len > 0 && ext_len < 4) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello message"));
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
}
/*
* mbedtls_ssl_derive_keys() has to be called after the parsing of the
* extensions. It sets the transform data for the resumed session which in
* case of DTLS includes the server CID extracted from the CID extension.
*/
if (ssl->handshake->resume) {
if ((ret = mbedtls_ssl_derive_keys(ssl)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_derive_keys", ret);
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR);
return ret;
}
}
/*
* Renegotiation security checks
*/
if (ssl->secure_renegotiation == MBEDTLS_SSL_LEGACY_RENEGOTIATION &&
ssl->conf->allow_legacy_renegotiation ==
MBEDTLS_SSL_LEGACY_BREAK_HANDSHAKE) {
MBEDTLS_SSL_DEBUG_MSG(1,
("legacy renegotiation, breaking off handshake"));
handshake_failure = 1;
}
#if defined(MBEDTLS_SSL_RENEGOTIATION)
else if (ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS &&
ssl->secure_renegotiation == MBEDTLS_SSL_SECURE_RENEGOTIATION &&
renegotiation_info_seen == 0) {
MBEDTLS_SSL_DEBUG_MSG(1,
("renegotiation_info extension missing (secure)"));
handshake_failure = 1;
} else if (ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS &&
ssl->secure_renegotiation == MBEDTLS_SSL_LEGACY_RENEGOTIATION &&
ssl->conf->allow_legacy_renegotiation ==
MBEDTLS_SSL_LEGACY_NO_RENEGOTIATION) {
MBEDTLS_SSL_DEBUG_MSG(1, ("legacy renegotiation not allowed"));
handshake_failure = 1;
} else if (ssl->renego_status == MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS &&
ssl->secure_renegotiation == MBEDTLS_SSL_LEGACY_RENEGOTIATION &&
renegotiation_info_seen == 1) {
MBEDTLS_SSL_DEBUG_MSG(1,
("renegotiation_info extension present (legacy)"));
handshake_failure = 1;
}
#endif /* MBEDTLS_SSL_RENEGOTIATION */
if (handshake_failure == 1) {
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO;
}
MBEDTLS_SSL_DEBUG_MSG(2, ("<= parse server hello"));
return 0;
}
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_server_dh_params(mbedtls_ssl_context *ssl,
unsigned char **p,
unsigned char *end)
{
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
size_t dhm_actual_bitlen;
/*
* Ephemeral DH parameters:
*
* struct {
* opaque dh_p<1..2^16-1>;
* opaque dh_g<1..2^16-1>;
* opaque dh_Ys<1..2^16-1>;
* } ServerDHParams;
*/
if ((ret = mbedtls_dhm_read_params(&ssl->handshake->dhm_ctx,
p, end)) != 0) {
MBEDTLS_SSL_DEBUG_RET(2, ("mbedtls_dhm_read_params"), ret);
return ret;
}
dhm_actual_bitlen = mbedtls_mpi_bitlen(&ssl->handshake->dhm_ctx.P);
if (dhm_actual_bitlen < ssl->conf->dhm_min_bitlen) {
MBEDTLS_SSL_DEBUG_MSG(1, ("DHM prime too short: %" MBEDTLS_PRINTF_SIZET " < %u",
dhm_actual_bitlen,
ssl->conf->dhm_min_bitlen));
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
MBEDTLS_SSL_DEBUG_MPI(3, "DHM: P ", &ssl->handshake->dhm_ctx.P);
MBEDTLS_SSL_DEBUG_MPI(3, "DHM: G ", &ssl->handshake->dhm_ctx.G);
MBEDTLS_SSL_DEBUG_MPI(3, "DHM: GY", &ssl->handshake->dhm_ctx.GY);
return ret;
}
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_check_server_ecdh_params(const mbedtls_ssl_context *ssl)
{
const mbedtls_ecp_curve_info *curve_info;
mbedtls_ecp_group_id grp_id;
#if defined(MBEDTLS_ECDH_LEGACY_CONTEXT)
grp_id = ssl->handshake->ecdh_ctx.grp.id;
#else
grp_id = ssl->handshake->ecdh_ctx.grp_id;
#endif /* MBEDTLS_ECDH_LEGACY_CONTEXT */
curve_info = mbedtls_ecp_curve_info_from_grp_id(grp_id);
if (curve_info == NULL) {
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
MBEDTLS_SSL_DEBUG_MSG(2, ("ECDH curve: %s", curve_info->name));
#if defined(MBEDTLS_ECP_C)
if (mbedtls_ssl_check_curve(ssl, grp_id) != 0) {
return -1;
}
#else
if (ssl->handshake->ecdh_ctx.grp.nbits < 163 ||
ssl->handshake->ecdh_ctx.grp.nbits > 521) {
return -1;
}
#endif /* MBEDTLS_ECP_C */
MBEDTLS_SSL_DEBUG_ECDH(3, &ssl->handshake->ecdh_ctx,
MBEDTLS_DEBUG_ECDH_QP);
return 0;
}
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
#if defined(MBEDTLS_USE_PSA_CRYPTO) && \
(defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED))
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_server_ecdh_params_psa(mbedtls_ssl_context *ssl,
unsigned char **p,
unsigned char *end)
{
uint16_t tls_id;
size_t ecdh_bits = 0;
uint8_t ecpoint_len;
mbedtls_ssl_handshake_params *handshake = ssl->handshake;
/*
* Parse ECC group
*/
if (end - *p < 4) {
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
/* First byte is curve_type; only named_curve is handled */
if (*(*p)++ != MBEDTLS_ECP_TLS_NAMED_CURVE) {
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
/* Next two bytes are the namedcurve value */
tls_id = *(*p)++;
tls_id <<= 8;
tls_id |= *(*p)++;
/* Check it's a curve we offered */
if (mbedtls_ssl_check_curve_tls_id(ssl, tls_id) != 0) {
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
/* Convert EC group to PSA key type. */
if ((handshake->ecdh_psa_type =
mbedtls_psa_parse_tls_ecc_group(tls_id, &ecdh_bits)) == 0) {
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
if (ecdh_bits > 0xffff) {
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
handshake->ecdh_bits = (uint16_t) ecdh_bits;
/*
* Put peer's ECDH public key in the format understood by PSA.
*/
ecpoint_len = *(*p)++;
if ((size_t) (end - *p) < ecpoint_len) {
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
if (mbedtls_psa_tls_ecpoint_to_psa_ec(
*p, ecpoint_len,
handshake->ecdh_psa_peerkey,
sizeof(handshake->ecdh_psa_peerkey),
&handshake->ecdh_psa_peerkey_len) != 0) {
return MBEDTLS_ERR_SSL_HW_ACCEL_FAILED;
}
*p += ecpoint_len;
return 0;
}
#endif /* MBEDTLS_USE_PSA_CRYPTO &&
( MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ) */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_server_ecdh_params(mbedtls_ssl_context *ssl,
unsigned char **p,
unsigned char *end)
{
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
/*
* Ephemeral ECDH parameters:
*
* struct {
* ECParameters curve_params;
* ECPoint public;
* } ServerECDHParams;
*/
if ((ret = mbedtls_ecdh_read_params(&ssl->handshake->ecdh_ctx,
(const unsigned char **) p, end)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, ("mbedtls_ecdh_read_params"), ret);
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ret == MBEDTLS_ERR_ECP_IN_PROGRESS) {
ret = MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS;
}
#endif
return ret;
}
if (ssl_check_server_ecdh_params(ssl) != 0) {
MBEDTLS_SSL_DEBUG_MSG(1,
("bad server key exchange message (ECDHE curve)"));
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
return ret;
}
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_server_psk_hint(mbedtls_ssl_context *ssl,
unsigned char **p,
unsigned char *end)
{
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
uint16_t len;
((void) ssl);
/*
* PSK parameters:
*
* opaque psk_identity_hint<0..2^16-1>;
*/
if (end - (*p) < 2) {
MBEDTLS_SSL_DEBUG_MSG(1,
("bad server key exchange message (psk_identity_hint length)"));
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
len = (*p)[0] << 8 | (*p)[1];
*p += 2;
if (end - (*p) < len) {
MBEDTLS_SSL_DEBUG_MSG(1,
("bad server key exchange message (psk_identity_hint length)"));
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
/*
* Note: we currently ignore the PSK identity hint, as we only allow one
* PSK to be provisioned on the client. This could be changed later if
* someone needs that feature.
*/
*p += len;
ret = 0;
return ret;
}
#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
/*
* Generate a pre-master secret and encrypt it with the server's RSA key
*/
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_encrypted_pms(mbedtls_ssl_context *ssl,
size_t offset, size_t *olen,
size_t pms_offset)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t len_bytes = ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_0 ? 0 : 2;
unsigned char *p = ssl->handshake->premaster + pms_offset;
mbedtls_pk_context *peer_pk;
if (offset + len_bytes > MBEDTLS_SSL_OUT_CONTENT_LEN) {
MBEDTLS_SSL_DEBUG_MSG(1, ("buffer too small for encrypted pms"));
return MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL;
}
/*
* Generate (part of) the pre-master as
* struct {
* ProtocolVersion client_version;
* opaque random[46];
* } PreMasterSecret;
*/
mbedtls_ssl_write_version(ssl->conf->max_major_ver,
ssl->conf->max_minor_ver,
ssl->conf->transport, p);
if ((ret = ssl->conf->f_rng(ssl->conf->p_rng, p + 2, 46)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "f_rng", ret);
return ret;
}
ssl->handshake->pmslen = 48;
#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
peer_pk = &ssl->handshake->peer_pubkey;
#else /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
if (ssl->session_negotiate->peer_cert == NULL) {
/* Should never happen */
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
peer_pk = &ssl->session_negotiate->peer_cert->pk;
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
/*
* Now write it out, encrypted
*/
if (!mbedtls_pk_can_do(peer_pk, MBEDTLS_PK_RSA)) {
MBEDTLS_SSL_DEBUG_MSG(1, ("certificate key type mismatch"));
return MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH;
}
if ((ret = mbedtls_pk_encrypt(peer_pk,
p, ssl->handshake->pmslen,
ssl->out_msg + offset + len_bytes, olen,
MBEDTLS_SSL_OUT_CONTENT_LEN - offset - len_bytes,
ssl->conf->f_rng, ssl->conf->p_rng)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_rsa_pkcs1_encrypt", ret);
return ret;
}
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
if (len_bytes == 2) {
MBEDTLS_PUT_UINT16_BE(*olen, ssl->out_msg, offset);
*olen += 2;
}
#endif
#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
/* We don't need the peer's public key anymore. Free it. */
mbedtls_pk_free(peer_pk);
#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
return 0;
}
#endif /* MBEDTLS_KEY_EXCHANGE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_signature_algorithm(mbedtls_ssl_context *ssl,
unsigned char **p,
unsigned char *end,
mbedtls_md_type_t *md_alg,
mbedtls_pk_type_t *pk_alg)
{
((void) ssl);
*md_alg = MBEDTLS_MD_NONE;
*pk_alg = MBEDTLS_PK_NONE;
/* Only in TLS 1.2 */
if (ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_3) {
return 0;
}
if ((*p) + 2 > end) {
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
/*
* Get hash algorithm
*/
if ((*md_alg = mbedtls_ssl_md_alg_from_hash((*p)[0]))
== MBEDTLS_MD_NONE) {
MBEDTLS_SSL_DEBUG_MSG(1,
("Server used unsupported HashAlgorithm %d", *(p)[0]));
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
/*
* Get signature algorithm
*/
if ((*pk_alg = mbedtls_ssl_pk_alg_from_sig((*p)[1]))
== MBEDTLS_PK_NONE) {
MBEDTLS_SSL_DEBUG_MSG(1,
("server used unsupported SignatureAlgorithm %d", (*p)[1]));
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
/*
* Check if the hash is acceptable
*/
if (mbedtls_ssl_check_sig_hash(ssl, *md_alg) != 0) {
MBEDTLS_SSL_DEBUG_MSG(1,
("server used HashAlgorithm %d that was not offered", *(p)[0]));
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
MBEDTLS_SSL_DEBUG_MSG(2, ("Server used SignatureAlgorithm %d",
(*p)[1]));
MBEDTLS_SSL_DEBUG_MSG(2, ("Server used HashAlgorithm %d",
(*p)[0]));
*p += 2;
return 0;
}
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_get_ecdh_params_from_cert(mbedtls_ssl_context *ssl)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
const mbedtls_ecp_keypair *peer_key;
mbedtls_pk_context *peer_pk;
#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
peer_pk = &ssl->handshake->peer_pubkey;
#else /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
if (ssl->session_negotiate->peer_cert == NULL) {
/* Should never happen */
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
peer_pk = &ssl->session_negotiate->peer_cert->pk;
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
/* This is a public key, so it can't be opaque, so can_do() is a good
* enough check to ensure pk_ec() is safe to use below. */
if (!mbedtls_pk_can_do(peer_pk, MBEDTLS_PK_ECKEY)) {
MBEDTLS_SSL_DEBUG_MSG(1, ("server key not ECDH capable"));
return MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH;
}
peer_key = mbedtls_pk_ec(*peer_pk);
if ((ret = mbedtls_ecdh_get_params(&ssl->handshake->ecdh_ctx, peer_key,
MBEDTLS_ECDH_THEIRS)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, ("mbedtls_ecdh_get_params"), ret);
return ret;
}
if (ssl_check_server_ecdh_params(ssl) != 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server certificate (ECDH curve)"));
return MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE;
}
#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
/* We don't need the peer's public key anymore. Free it,
* so that more RAM is available for upcoming expensive
* operations like ECDHE. */
mbedtls_pk_free(peer_pk);
#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
return ret;
}
#endif /* MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) ||
MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_server_key_exchange(mbedtls_ssl_context *ssl)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
ssl->handshake->ciphersuite_info;
unsigned char *p = NULL, *end = NULL;
MBEDTLS_SSL_DEBUG_MSG(2, ("=> parse server key exchange"));
#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA) {
MBEDTLS_SSL_DEBUG_MSG(2, ("<= skip parse server key exchange"));
ssl->state++;
return 0;
}
((void) p);
((void) end);
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA) {
if ((ret = ssl_get_ecdh_params_from_cert(ssl)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "ssl_get_ecdh_params_from_cert", ret);
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return ret;
}
MBEDTLS_SSL_DEBUG_MSG(2, ("<= skip parse server key exchange"));
ssl->state++;
return 0;
}
((void) p);
((void) end);
#endif /* MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ssl->handshake->ecrs_enabled &&
ssl->handshake->ecrs_state == ssl_ecrs_ske_start_processing) {
goto start_processing;
}
#endif
if ((ret = mbedtls_ssl_read_record(ssl, 1)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_read_record", ret);
return ret;
}
if (ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server key exchange message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE);
return MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE;
}
/*
* ServerKeyExchange may be skipped with PSK and RSA-PSK when the server
* doesn't use a psk_identity_hint
*/
if (ssl->in_msg[0] != MBEDTLS_SSL_HS_SERVER_KEY_EXCHANGE) {
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK) {
/* Current message is probably either
* CertificateRequest or ServerHelloDone */
ssl->keep_current_message = 1;
goto exit;
}
MBEDTLS_SSL_DEBUG_MSG(1,
("server key exchange message must not be skipped"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE);
return MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE;
}
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ssl->handshake->ecrs_enabled) {
ssl->handshake->ecrs_state = ssl_ecrs_ske_start_processing;
}
start_processing:
#endif
p = ssl->in_msg + mbedtls_ssl_hs_hdr_len(ssl);
end = ssl->in_msg + ssl->in_hslen;
MBEDTLS_SSL_DEBUG_BUF(3, "server key exchange", p, end - p);
#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK) {
if (ssl_parse_server_psk_hint(ssl, &p, end) != 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server key exchange message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
} /* FALLTHROUGH */
#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK) {
; /* nothing more to do */
} else
#endif /* MBEDTLS_KEY_EXCHANGE_PSK_ENABLED ||
MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK) {
if (ssl_parse_server_dh_params(ssl, &p, end) != 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server key exchange message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
} else
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */
#if defined(MBEDTLS_USE_PSA_CRYPTO) && \
(defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED))
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA) {
if (ssl_parse_server_ecdh_params_psa(ssl, &p, end) != 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server key exchange message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
} else
#endif /* MBEDTLS_USE_PSA_CRYPTO &&
( MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ) */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA) {
if (ssl_parse_server_ecdh_params(ssl, &p, end) != 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server key exchange message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
} else
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE) {
ret = mbedtls_ecjpake_read_round_two(&ssl->handshake->ecjpake_ctx,
p, end - p);
if (ret != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ecjpake_read_round_two", ret);
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
} else
#endif /* MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
{
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
#if defined(MBEDTLS_KEY_EXCHANGE_WITH_SERVER_SIGNATURE_ENABLED)
if (mbedtls_ssl_ciphersuite_uses_server_signature(ciphersuite_info)) {
size_t sig_len, hashlen;
#if defined(MBEDTLS_USE_PSA_CRYPTO)
unsigned char hash[PSA_HASH_MAX_SIZE];
#else
unsigned char hash[MBEDTLS_MD_MAX_SIZE];
#endif
mbedtls_md_type_t md_alg = MBEDTLS_MD_NONE;
mbedtls_pk_type_t pk_alg = MBEDTLS_PK_NONE;
unsigned char *params = ssl->in_msg + mbedtls_ssl_hs_hdr_len(ssl);
size_t params_len = p - params;
void *rs_ctx = NULL;
mbedtls_pk_context *peer_pk;
/*
* Handle the digitally-signed structure
*/
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if (ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3) {
if (ssl_parse_signature_algorithm(ssl, &p, end,
&md_alg, &pk_alg) != 0) {
MBEDTLS_SSL_DEBUG_MSG(1,
("bad server key exchange message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
if (pk_alg !=
mbedtls_ssl_get_ciphersuite_sig_pk_alg(ciphersuite_info)) {
MBEDTLS_SSL_DEBUG_MSG(1,
("bad server key exchange message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
} else
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
if (ssl->minor_ver < MBEDTLS_SSL_MINOR_VERSION_3) {
pk_alg = mbedtls_ssl_get_ciphersuite_sig_pk_alg(ciphersuite_info);
/* Default hash for ECDSA is SHA-1 */
if (pk_alg == MBEDTLS_PK_ECDSA && md_alg == MBEDTLS_MD_NONE) {
md_alg = MBEDTLS_MD_SHA1;
}
} else
#endif
{
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
/*
* Read signature
*/
if (p > end - 2) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server key exchange message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
sig_len = (p[0] << 8) | p[1];
p += 2;
if (p != end - sig_len) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server key exchange message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_KEY_EXCHANGE;
}
MBEDTLS_SSL_DEBUG_BUF(3, "signature", p, sig_len);
/*
* Compute the hash that has been signed
*/
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
if (md_alg == MBEDTLS_MD_NONE) {
hashlen = 36;
ret = mbedtls_ssl_get_key_exchange_md_ssl_tls(ssl, hash, params,
params_len);
if (ret != 0) {
return ret;
}
} else
#endif /* MBEDTLS_SSL_PROTO_SSL3 || MBEDTLS_SSL_PROTO_TLS1 || \
MBEDTLS_SSL_PROTO_TLS1_1 */
#if defined(MBEDTLS_SSL_PROTO_TLS1) || defined(MBEDTLS_SSL_PROTO_TLS1_1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_2)
if (md_alg != MBEDTLS_MD_NONE) {
ret = mbedtls_ssl_get_key_exchange_md_tls1_2(ssl, hash, &hashlen,
params, params_len,
md_alg);
if (ret != 0) {
return ret;
}
} else
#endif /* MBEDTLS_SSL_PROTO_TLS1 || MBEDTLS_SSL_PROTO_TLS1_1 || \
MBEDTLS_SSL_PROTO_TLS1_2 */
{
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
MBEDTLS_SSL_DEBUG_BUF(3, "parameters hash", hash, hashlen);
#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
peer_pk = &ssl->handshake->peer_pubkey;
#else /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
if (ssl->session_negotiate->peer_cert == NULL) {
/* Should never happen */
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
peer_pk = &ssl->session_negotiate->peer_cert->pk;
#endif /* MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
/*
* Verify signature
*/
if (!mbedtls_pk_can_do(peer_pk, pk_alg)) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server key exchange message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE);
return MBEDTLS_ERR_SSL_PK_TYPE_MISMATCH;
}
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ssl->handshake->ecrs_enabled) {
rs_ctx = &ssl->handshake->ecrs_ctx.pk;
}
#endif /* MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED */
if ((ret = mbedtls_pk_verify_restartable(peer_pk,
md_alg, hash, hashlen, p, sig_len, rs_ctx)) != 0) {
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ret == MBEDTLS_ERR_ECP_IN_PROGRESS) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_pk_verify", ret);
return MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS;
}
#endif /* MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED */
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR);
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_pk_verify", ret);
return ret;
}
#if !defined(MBEDTLS_SSL_KEEP_PEER_CERTIFICATE)
/* We don't need the peer's public key anymore. Free it,
* so that more RAM is available for upcoming expensive
* operations like ECDHE. */
mbedtls_pk_free(peer_pk);
#endif /* !MBEDTLS_SSL_KEEP_PEER_CERTIFICATE */
}
#endif /* MBEDTLS_KEY_EXCHANGE_WITH_SERVER_SIGNATURE_ENABLED */
exit:
ssl->state++;
MBEDTLS_SSL_DEBUG_MSG(2, ("<= parse server key exchange"));
return 0;
}
#if !defined(MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_certificate_request(mbedtls_ssl_context *ssl)
{
const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
ssl->handshake->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG(2, ("=> parse certificate request"));
if (!mbedtls_ssl_ciphersuite_cert_req_allowed(ciphersuite_info)) {
MBEDTLS_SSL_DEBUG_MSG(2, ("<= skip parse certificate request"));
ssl->state++;
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
#else /* MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_certificate_request(mbedtls_ssl_context *ssl)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char *buf;
size_t n = 0;
size_t cert_type_len = 0, dn_len = 0;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
ssl->handshake->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG(2, ("=> parse certificate request"));
if (!mbedtls_ssl_ciphersuite_cert_req_allowed(ciphersuite_info)) {
MBEDTLS_SSL_DEBUG_MSG(2, ("<= skip parse certificate request"));
ssl->state++;
return 0;
}
if ((ret = mbedtls_ssl_read_record(ssl, 1)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_read_record", ret);
return ret;
}
if (ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad certificate request message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE);
return MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE;
}
ssl->state++;
ssl->client_auth = (ssl->in_msg[0] == MBEDTLS_SSL_HS_CERTIFICATE_REQUEST);
MBEDTLS_SSL_DEBUG_MSG(3, ("got %s certificate request",
ssl->client_auth ? "a" : "no"));
if (ssl->client_auth == 0) {
/* Current message is probably the ServerHelloDone */
ssl->keep_current_message = 1;
goto exit;
}
/*
* struct {
* ClientCertificateType certificate_types<1..2^8-1>;
* SignatureAndHashAlgorithm
* supported_signature_algorithms<2^16-1>; -- TLS 1.2 only
* DistinguishedName certificate_authorities<0..2^16-1>;
* } CertificateRequest;
*
* Since we only support a single certificate on clients, let's just
* ignore all the information that's supposed to help us pick a
* certificate.
*
* We could check that our certificate matches the request, and bail out
* if it doesn't, but it's simpler to just send the certificate anyway,
* and give the server the opportunity to decide if it should terminate
* the connection when it doesn't like our certificate.
*
* Same goes for the hash in TLS 1.2's signature_algorithms: at this
* point we only have one hash available (see comments in
* write_certificate_verify), so let's just use what we have.
*
* However, we still minimally parse the message to check it is at least
* superficially sane.
*/
buf = ssl->in_msg;
/* certificate_types */
if (ssl->in_hslen <= mbedtls_ssl_hs_hdr_len(ssl)) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad certificate request message"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST;
}
cert_type_len = buf[mbedtls_ssl_hs_hdr_len(ssl)];
n = cert_type_len;
/*
* In the subsequent code there are two paths that read from buf:
* * the length of the signature algorithms field (if minor version of
* SSL is 3),
* * distinguished name length otherwise.
* Both reach at most the index:
* ...hdr_len + 2 + n,
* therefore the buffer length at this point must be greater than that
* regardless of the actual code path.
*/
if (ssl->in_hslen <= mbedtls_ssl_hs_hdr_len(ssl) + 2 + n) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad certificate request message"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST;
}
/* supported_signature_algorithms */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if (ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3) {
size_t sig_alg_len =
((buf[mbedtls_ssl_hs_hdr_len(ssl) + 1 + n] << 8)
| (buf[mbedtls_ssl_hs_hdr_len(ssl) + 2 + n]));
#if defined(MBEDTLS_DEBUG_C)
unsigned char *sig_alg;
size_t i;
#endif
/*
* The furthest access in buf is in the loop few lines below:
* sig_alg[i + 1],
* where:
* sig_alg = buf + ...hdr_len + 3 + n,
* max(i) = sig_alg_len - 1.
* Therefore the furthest access is:
* buf[...hdr_len + 3 + n + sig_alg_len - 1 + 1],
* which reduces to:
* buf[...hdr_len + 3 + n + sig_alg_len],
* which is one less than we need the buf to be.
*/
if (ssl->in_hslen <= mbedtls_ssl_hs_hdr_len(ssl)
+ 3 + n + sig_alg_len) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad certificate request message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST;
}
#if defined(MBEDTLS_DEBUG_C)
sig_alg = buf + mbedtls_ssl_hs_hdr_len(ssl) + 3 + n;
for (i = 0; i < sig_alg_len; i += 2) {
MBEDTLS_SSL_DEBUG_MSG(3,
("Supported Signature Algorithm found: %d,%d",
sig_alg[i], sig_alg[i + 1]));
}
#endif
n += 2 + sig_alg_len;
}
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
/* certificate_authorities */
dn_len = ((buf[mbedtls_ssl_hs_hdr_len(ssl) + 1 + n] << 8)
| (buf[mbedtls_ssl_hs_hdr_len(ssl) + 2 + n]));
n += dn_len;
if (ssl->in_hslen != mbedtls_ssl_hs_hdr_len(ssl) + 3 + n) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad certificate request message"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_CERTIFICATE_REQUEST;
}
exit:
MBEDTLS_SSL_DEBUG_MSG(2, ("<= parse certificate request"));
return 0;
}
#endif /* MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_server_hello_done(mbedtls_ssl_context *ssl)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
MBEDTLS_SSL_DEBUG_MSG(2, ("=> parse server hello done"));
if ((ret = mbedtls_ssl_read_record(ssl, 1)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_read_record", ret);
return ret;
}
if (ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello done message"));
return MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE;
}
if (ssl->in_hslen != mbedtls_ssl_hs_hdr_len(ssl) ||
ssl->in_msg[0] != MBEDTLS_SSL_HS_SERVER_HELLO_DONE) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad server hello done message"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO_DONE;
}
ssl->state++;
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM) {
mbedtls_ssl_recv_flight_completed(ssl);
}
#endif
MBEDTLS_SSL_DEBUG_MSG(2, ("<= parse server hello done"));
return 0;
}
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_client_key_exchange(mbedtls_ssl_context *ssl)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
size_t header_len;
size_t content_len;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
ssl->handshake->ciphersuite_info;
MBEDTLS_SSL_DEBUG_MSG(2, ("=> write client key exchange"));
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_RSA) {
/*
* DHM key exchange -- send G^X mod P
*/
content_len = ssl->handshake->dhm_ctx.len;
MBEDTLS_PUT_UINT16_BE(content_len, ssl->out_msg, 4);
header_len = 6;
ret = mbedtls_dhm_make_public(&ssl->handshake->dhm_ctx,
(int) mbedtls_mpi_size(&ssl->handshake->dhm_ctx.P),
&ssl->out_msg[header_len], content_len,
ssl->conf->f_rng, ssl->conf->p_rng);
if (ret != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_dhm_make_public", ret);
return ret;
}
MBEDTLS_SSL_DEBUG_MPI(3, "DHM: X ", &ssl->handshake->dhm_ctx.X);
MBEDTLS_SSL_DEBUG_MPI(3, "DHM: GX", &ssl->handshake->dhm_ctx.GX);
if ((ret = mbedtls_dhm_calc_secret(&ssl->handshake->dhm_ctx,
ssl->handshake->premaster,
MBEDTLS_PREMASTER_SIZE,
&ssl->handshake->pmslen,
ssl->conf->f_rng, ssl->conf->p_rng)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_dhm_calc_secret", ret);
return ret;
}
MBEDTLS_SSL_DEBUG_MPI(3, "DHM: K ", &ssl->handshake->dhm_ctx.K);
} else
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_RSA_ENABLED */
#if defined(MBEDTLS_USE_PSA_CRYPTO) && \
(defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED))
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA) {
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t destruction_status = PSA_ERROR_CORRUPTION_DETECTED;
psa_key_attributes_t key_attributes;
mbedtls_ssl_handshake_params *handshake = ssl->handshake;
unsigned char own_pubkey[MBEDTLS_PSA_MAX_EC_PUBKEY_LENGTH];
size_t own_pubkey_len;
unsigned char *own_pubkey_ecpoint;
size_t own_pubkey_ecpoint_len;
header_len = 4;
MBEDTLS_SSL_DEBUG_MSG(1, ("Perform PSA-based ECDH computation."));
/*
* Generate EC private key for ECDHE exchange.
*/
/* The master secret is obtained from the shared ECDH secret by
* applying the TLS 1.2 PRF with a specific salt and label. While
* the PSA Crypto API encourages combining key agreement schemes
* such as ECDH with fixed KDFs such as TLS 1.2 PRF, it does not
* yet support the provisioning of salt + label to the KDF.
* For the time being, we therefore need to split the computation
* of the ECDH secret and the application of the TLS 1.2 PRF. */
key_attributes = psa_key_attributes_init();
psa_set_key_usage_flags(&key_attributes, PSA_KEY_USAGE_DERIVE);
psa_set_key_algorithm(&key_attributes, PSA_ALG_ECDH);
psa_set_key_type(&key_attributes, handshake->ecdh_psa_type);
psa_set_key_bits(&key_attributes, handshake->ecdh_bits);
/* Generate ECDH private key. */
status = psa_generate_key(&key_attributes,
&handshake->ecdh_psa_privkey);
if (status != PSA_SUCCESS) {
return MBEDTLS_ERR_SSL_HW_ACCEL_FAILED;
}
/* Export the public part of the ECDH private key from PSA
* and convert it to ECPoint format used in ClientKeyExchange. */
status = psa_export_public_key(handshake->ecdh_psa_privkey,
own_pubkey, sizeof(own_pubkey),
&own_pubkey_len);
if (status != PSA_SUCCESS) {
psa_destroy_key(handshake->ecdh_psa_privkey);
handshake->ecdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT;
return MBEDTLS_ERR_SSL_HW_ACCEL_FAILED;
}
if (mbedtls_psa_tls_psa_ec_to_ecpoint(own_pubkey,
own_pubkey_len,
&own_pubkey_ecpoint,
&own_pubkey_ecpoint_len) != 0) {
psa_destroy_key(handshake->ecdh_psa_privkey);
handshake->ecdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT;
return MBEDTLS_ERR_SSL_HW_ACCEL_FAILED;
}
/* Copy ECPoint structure to outgoing message buffer. */
ssl->out_msg[header_len] = (unsigned char) own_pubkey_ecpoint_len;
memcpy(ssl->out_msg + header_len + 1,
own_pubkey_ecpoint, own_pubkey_ecpoint_len);
content_len = own_pubkey_ecpoint_len + 1;
/* The ECDH secret is the premaster secret used for key derivation. */
/* Compute ECDH shared secret. */
status = psa_raw_key_agreement(PSA_ALG_ECDH,
handshake->ecdh_psa_privkey,
handshake->ecdh_psa_peerkey,
handshake->ecdh_psa_peerkey_len,
ssl->handshake->premaster,
sizeof(ssl->handshake->premaster),
&ssl->handshake->pmslen);
destruction_status = psa_destroy_key(handshake->ecdh_psa_privkey);
handshake->ecdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT;
if (status != PSA_SUCCESS || destruction_status != PSA_SUCCESS) {
return MBEDTLS_ERR_SSL_HW_ACCEL_FAILED;
}
} else
#endif /* MBEDTLS_USE_PSA_CRYPTO &&
( MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ) */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \
defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA) {
/*
* ECDH key exchange -- send client public value
*/
header_len = 4;
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ssl->handshake->ecrs_enabled) {
if (ssl->handshake->ecrs_state == ssl_ecrs_cke_ecdh_calc_secret) {
goto ecdh_calc_secret;
}
mbedtls_ecdh_enable_restart(&ssl->handshake->ecdh_ctx);
}
#endif
ret = mbedtls_ecdh_make_public(&ssl->handshake->ecdh_ctx,
&content_len,
&ssl->out_msg[header_len], 1000,
ssl->conf->f_rng, ssl->conf->p_rng);
if (ret != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ecdh_make_public", ret);
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ret == MBEDTLS_ERR_ECP_IN_PROGRESS) {
ret = MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS;
}
#endif
return ret;
}
MBEDTLS_SSL_DEBUG_ECDH(3, &ssl->handshake->ecdh_ctx,
MBEDTLS_DEBUG_ECDH_Q);
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ssl->handshake->ecrs_enabled) {
ssl->handshake->ecrs_n = content_len;
ssl->handshake->ecrs_state = ssl_ecrs_cke_ecdh_calc_secret;
}
ecdh_calc_secret:
if (ssl->handshake->ecrs_enabled) {
content_len = ssl->handshake->ecrs_n;
}
#endif
if ((ret = mbedtls_ecdh_calc_secret(&ssl->handshake->ecdh_ctx,
&ssl->handshake->pmslen,
ssl->handshake->premaster,
MBEDTLS_MPI_MAX_SIZE,
ssl->conf->f_rng, ssl->conf->p_rng)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ecdh_calc_secret", ret);
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ret == MBEDTLS_ERR_ECP_IN_PROGRESS) {
ret = MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS;
}
#endif
return ret;
}
MBEDTLS_SSL_DEBUG_ECDH(3, &ssl->handshake->ecdh_ctx,
MBEDTLS_DEBUG_ECDH_Z);
} else
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED ||
MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
if (mbedtls_ssl_ciphersuite_uses_psk(ciphersuite_info)) {
/*
* opaque psk_identity<0..2^16-1>;
*/
if (ssl_conf_has_static_psk(ssl->conf) == 0) {
/* We don't offer PSK suites if we don't have a PSK,
* and we check that the server's choice is among the
* ciphersuites we offered, so this should never happen. */
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
header_len = 4;
content_len = ssl->conf->psk_identity_len;
if (header_len + 2 + content_len > MBEDTLS_SSL_OUT_CONTENT_LEN) {
MBEDTLS_SSL_DEBUG_MSG(1,
("psk identity too long or SSL buffer too short"));
return MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL;
}
ssl->out_msg[header_len++] = MBEDTLS_BYTE_1(content_len);
ssl->out_msg[header_len++] = MBEDTLS_BYTE_0(content_len);
memcpy(ssl->out_msg + header_len,
ssl->conf->psk_identity,
ssl->conf->psk_identity_len);
header_len += ssl->conf->psk_identity_len;
#if defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK) {
content_len = 0;
} else
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_RSA_PSK_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA_PSK) {
#if defined(MBEDTLS_USE_PSA_CRYPTO)
/* Opaque PSKs are currently only supported for PSK-only suites. */
if (ssl_conf_has_static_raw_psk(ssl->conf) == 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("opaque PSK not supported with RSA-PSK"));
return MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
if ((ret = ssl_write_encrypted_pms(ssl, header_len,
&content_len, 2)) != 0) {
return ret;
}
} else
#endif
#if defined(MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_DHE_PSK) {
#if defined(MBEDTLS_USE_PSA_CRYPTO)
/* Opaque PSKs are currently only supported for PSK-only suites. */
if (ssl_conf_has_static_raw_psk(ssl->conf) == 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("opaque PSK not supported with DHE-PSK"));
return MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
/*
* ClientDiffieHellmanPublic public (DHM send G^X mod P)
*/
content_len = ssl->handshake->dhm_ctx.len;
if (header_len + 2 + content_len >
MBEDTLS_SSL_OUT_CONTENT_LEN) {
MBEDTLS_SSL_DEBUG_MSG(1,
("psk identity or DHM size too long or SSL buffer too short"));
return MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL;
}
ssl->out_msg[header_len++] = MBEDTLS_BYTE_1(content_len);
ssl->out_msg[header_len++] = MBEDTLS_BYTE_0(content_len);
ret = mbedtls_dhm_make_public(&ssl->handshake->dhm_ctx,
(int) mbedtls_mpi_size(&ssl->handshake->dhm_ctx.P),
&ssl->out_msg[header_len], content_len,
ssl->conf->f_rng, ssl->conf->p_rng);
if (ret != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_dhm_make_public", ret);
return ret;
}
} else
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK) {
#if defined(MBEDTLS_USE_PSA_CRYPTO)
/* Opaque PSKs are currently only supported for PSK-only suites. */
if (ssl_conf_has_static_raw_psk(ssl->conf) == 0) {
MBEDTLS_SSL_DEBUG_MSG(1, ("opaque PSK not supported with ECDHE-PSK"));
return MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
}
#endif /* MBEDTLS_USE_PSA_CRYPTO */
/*
* ClientECDiffieHellmanPublic public;
*/
ret = mbedtls_ecdh_make_public(&ssl->handshake->ecdh_ctx,
&content_len,
&ssl->out_msg[header_len],
MBEDTLS_SSL_OUT_CONTENT_LEN - header_len,
ssl->conf->f_rng, ssl->conf->p_rng);
if (ret != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ecdh_make_public", ret);
return ret;
}
MBEDTLS_SSL_DEBUG_ECDH(3, &ssl->handshake->ecdh_ctx,
MBEDTLS_DEBUG_ECDH_Q);
} else
#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */
{
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
#if defined(MBEDTLS_USE_PSA_CRYPTO) && \
defined(MBEDTLS_KEY_EXCHANGE_PSK_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_PSK &&
ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3 &&
ssl_conf_has_static_raw_psk(ssl->conf) == 0) {
MBEDTLS_SSL_DEBUG_MSG(1,
("skip PMS generation for opaque PSK"));
} else
#endif /* MBEDTLS_USE_PSA_CRYPTO &&
MBEDTLS_KEY_EXCHANGE_PSK_ENABLED */
if ((ret = mbedtls_ssl_psk_derive_premaster(ssl,
ciphersuite_info->key_exchange)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1,
"mbedtls_ssl_psk_derive_premaster", ret);
return ret;
}
} else
#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_RSA_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_RSA) {
header_len = 4;
if ((ret = ssl_write_encrypted_pms(ssl, header_len,
&content_len, 0)) != 0) {
return ret;
}
} else
#endif /* MBEDTLS_KEY_EXCHANGE_RSA_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECJPAKE) {
header_len = 4;
ret = mbedtls_ecjpake_write_round_two(&ssl->handshake->ecjpake_ctx,
ssl->out_msg + header_len,
MBEDTLS_SSL_OUT_CONTENT_LEN - header_len,
&content_len,
ssl->conf->f_rng, ssl->conf->p_rng);
if (ret != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ecjpake_write_round_two", ret);
return ret;
}
ret = mbedtls_ecjpake_derive_secret(&ssl->handshake->ecjpake_ctx,
ssl->handshake->premaster, 32, &ssl->handshake->pmslen,
ssl->conf->f_rng, ssl->conf->p_rng);
if (ret != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ecjpake_derive_secret", ret);
return ret;
}
} else
#endif /* MBEDTLS_KEY_EXCHANGE_RSA_ENABLED */
{
((void) ciphersuite_info);
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
ssl->out_msglen = header_len + content_len;
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = MBEDTLS_SSL_HS_CLIENT_KEY_EXCHANGE;
ssl->state++;
if ((ret = mbedtls_ssl_write_handshake_msg(ssl)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_write_handshake_msg", ret);
return ret;
}
MBEDTLS_SSL_DEBUG_MSG(2, ("<= write client key exchange"));
return 0;
}
#if !defined(MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_certificate_verify(mbedtls_ssl_context *ssl)
{
const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
ssl->handshake->ciphersuite_info;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
MBEDTLS_SSL_DEBUG_MSG(2, ("=> write certificate verify"));
if ((ret = mbedtls_ssl_derive_keys(ssl)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_derive_keys", ret);
return ret;
}
if (!mbedtls_ssl_ciphersuite_cert_req_allowed(ciphersuite_info)) {
MBEDTLS_SSL_DEBUG_MSG(2, ("<= skip write certificate verify"));
ssl->state++;
return 0;
}
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
#else /* !MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_write_certificate_verify(mbedtls_ssl_context *ssl)
{
int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE;
const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
ssl->handshake->ciphersuite_info;
size_t n = 0, offset = 0;
unsigned char hash[48];
unsigned char *hash_start = hash;
mbedtls_md_type_t md_alg = MBEDTLS_MD_NONE;
size_t hashlen;
void *rs_ctx = NULL;
MBEDTLS_SSL_DEBUG_MSG(2, ("=> write certificate verify"));
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ssl->handshake->ecrs_enabled &&
ssl->handshake->ecrs_state == ssl_ecrs_crt_vrfy_sign) {
goto sign;
}
#endif
if ((ret = mbedtls_ssl_derive_keys(ssl)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_derive_keys", ret);
return ret;
}
if (!mbedtls_ssl_ciphersuite_cert_req_allowed(ciphersuite_info)) {
MBEDTLS_SSL_DEBUG_MSG(2, ("<= skip write certificate verify"));
ssl->state++;
return 0;
}
if (ssl->client_auth == 0 || mbedtls_ssl_own_cert(ssl) == NULL) {
MBEDTLS_SSL_DEBUG_MSG(2, ("<= skip write certificate verify"));
ssl->state++;
return 0;
}
if (mbedtls_ssl_own_key(ssl) == NULL) {
MBEDTLS_SSL_DEBUG_MSG(1, ("got no private key for certificate"));
return MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED;
}
/*
* Make a signature of the handshake digests
*/
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ssl->handshake->ecrs_enabled) {
ssl->handshake->ecrs_state = ssl_ecrs_crt_vrfy_sign;
}
sign:
#endif
ssl->handshake->calc_verify(ssl, hash, &hashlen);
#if defined(MBEDTLS_SSL_PROTO_SSL3) || defined(MBEDTLS_SSL_PROTO_TLS1) || \
defined(MBEDTLS_SSL_PROTO_TLS1_1)
if (ssl->minor_ver != MBEDTLS_SSL_MINOR_VERSION_3) {
/*
* digitally-signed struct {
* opaque md5_hash[16];
* opaque sha_hash[20];
* };
*
* md5_hash
* MD5(handshake_messages);
*
* sha_hash
* SHA(handshake_messages);
*/
md_alg = MBEDTLS_MD_NONE;
/*
* For ECDSA, default hash is SHA-1 only
*/
if (mbedtls_pk_can_do(mbedtls_ssl_own_key(ssl), MBEDTLS_PK_ECDSA)) {
hash_start += 16;
hashlen -= 16;
md_alg = MBEDTLS_MD_SHA1;
}
} else
#endif /* MBEDTLS_SSL_PROTO_SSL3 || MBEDTLS_SSL_PROTO_TLS1 || \
MBEDTLS_SSL_PROTO_TLS1_1 */
#if defined(MBEDTLS_SSL_PROTO_TLS1_2)
if (ssl->minor_ver == MBEDTLS_SSL_MINOR_VERSION_3) {
/*
* digitally-signed struct {
* opaque handshake_messages[handshake_messages_length];
* };
*
* Taking shortcut here. We assume that the server always allows the
* PRF Hash function and has sent it in the allowed signature
* algorithms list received in the Certificate Request message.
*
* Until we encounter a server that does not, we will take this
* shortcut.
*
* Reason: Otherwise we should have running hashes for SHA512 and
* SHA224 in order to satisfy 'weird' needs from the server
* side.
*/
if (ssl->handshake->ciphersuite_info->mac == MBEDTLS_MD_SHA384) {
md_alg = MBEDTLS_MD_SHA384;
ssl->out_msg[4] = MBEDTLS_SSL_HASH_SHA384;
} else {
md_alg = MBEDTLS_MD_SHA256;
ssl->out_msg[4] = MBEDTLS_SSL_HASH_SHA256;
}
ssl->out_msg[5] = mbedtls_ssl_sig_from_pk(mbedtls_ssl_own_key(ssl));
/* Info from md_alg will be used instead */
hashlen = 0;
offset = 2;
} else
#endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
{
MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen"));
return MBEDTLS_ERR_SSL_INTERNAL_ERROR;
}
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ssl->handshake->ecrs_enabled) {
rs_ctx = &ssl->handshake->ecrs_ctx.pk;
}
#endif
if ((ret = mbedtls_pk_sign_restartable(mbedtls_ssl_own_key(ssl),
md_alg, hash_start, hashlen,
ssl->out_msg + 6 + offset, &n,
ssl->conf->f_rng, ssl->conf->p_rng, rs_ctx)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_pk_sign", ret);
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
if (ret == MBEDTLS_ERR_ECP_IN_PROGRESS) {
ret = MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS;
}
#endif
return ret;
}
MBEDTLS_PUT_UINT16_BE(n, ssl->out_msg, offset + 4);
ssl->out_msglen = 6 + n + offset;
ssl->out_msgtype = MBEDTLS_SSL_MSG_HANDSHAKE;
ssl->out_msg[0] = MBEDTLS_SSL_HS_CERTIFICATE_VERIFY;
ssl->state++;
if ((ret = mbedtls_ssl_write_handshake_msg(ssl)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_write_handshake_msg", ret);
return ret;
}
MBEDTLS_SSL_DEBUG_MSG(2, ("<= write certificate verify"));
return ret;
}
#endif /* MBEDTLS_KEY_EXCHANGE_CERT_REQ_ALLOWED_ENABLED */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
MBEDTLS_CHECK_RETURN_CRITICAL
static int ssl_parse_new_session_ticket(mbedtls_ssl_context *ssl)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
uint32_t lifetime;
size_t ticket_len;
unsigned char *ticket;
const unsigned char *msg;
MBEDTLS_SSL_DEBUG_MSG(2, ("=> parse new session ticket"));
if ((ret = mbedtls_ssl_read_record(ssl, 1)) != 0) {
MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_read_record", ret);
return ret;
}
if (ssl->in_msgtype != MBEDTLS_SSL_MSG_HANDSHAKE) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad new session ticket message"));
mbedtls_ssl_send_alert_message(
ssl,
MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_UNEXPECTED_MESSAGE);
return MBEDTLS_ERR_SSL_UNEXPECTED_MESSAGE;
}
/*
* struct {
* uint32 ticket_lifetime_hint;
* opaque ticket<0..2^16-1>;
* } NewSessionTicket;
*
* 0 . 3 ticket_lifetime_hint
* 4 . 5 ticket_len (n)
* 6 . 5+n ticket content
*/
if (ssl->in_msg[0] != MBEDTLS_SSL_HS_NEW_SESSION_TICKET ||
ssl->in_hslen < 6 + mbedtls_ssl_hs_hdr_len(ssl)) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad new session ticket message"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET;
}
msg = ssl->in_msg + mbedtls_ssl_hs_hdr_len(ssl);
lifetime = (((uint32_t) msg[0]) << 24) | (msg[1] << 16) |
(msg[2] << 8) | (msg[3]);
ticket_len = (msg[4] << 8) | (msg[5]);
if (ticket_len + 6 + mbedtls_ssl_hs_hdr_len(ssl) != ssl->in_hslen) {
MBEDTLS_SSL_DEBUG_MSG(1, ("bad new session ticket message"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR);
return MBEDTLS_ERR_SSL_BAD_HS_NEW_SESSION_TICKET;
}
MBEDTLS_SSL_DEBUG_MSG(3, ("ticket length: %" MBEDTLS_PRINTF_SIZET, ticket_len));
/* We're not waiting for a NewSessionTicket message any more */
ssl->handshake->new_session_ticket = 0;
ssl->state = MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC;
/*
* Zero-length ticket means the server changed his mind and doesn't want
* to send a ticket after all, so just forget it
*/
if (ticket_len == 0) {
return 0;
}
if (ssl->session != NULL && ssl->session->ticket != NULL) {
mbedtls_platform_zeroize(ssl->session->ticket,
ssl->session->ticket_len);
mbedtls_free(ssl->session->ticket);
ssl->session->ticket = NULL;
ssl->session->ticket_len = 0;
}
mbedtls_platform_zeroize(ssl->session_negotiate->ticket,
ssl->session_negotiate->ticket_len);
mbedtls_free(ssl->session_negotiate->ticket);
ssl->session_negotiate->ticket = NULL;
ssl->session_negotiate->ticket_len = 0;
if ((ticket = mbedtls_calloc(1, ticket_len)) == NULL) {
MBEDTLS_SSL_DEBUG_MSG(1, ("ticket alloc failed"));
mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
MBEDTLS_SSL_ALERT_MSG_INTERNAL_ERROR);
return MBEDTLS_ERR_SSL_ALLOC_FAILED;
}
memcpy(ticket, msg + 6, ticket_len);
ssl->session_negotiate->ticket = ticket;
ssl->session_negotiate->ticket_len = ticket_len;
ssl->session_negotiate->ticket_lifetime = lifetime;
/*
* RFC 5077 section 3.4:
* "If the client receives a session ticket from the server, then it
* discards any Session ID that was sent in the ServerHello."
*/
MBEDTLS_SSL_DEBUG_MSG(3, ("ticket in use, discarding session id"));
ssl->session_negotiate->id_len = 0;
MBEDTLS_SSL_DEBUG_MSG(2, ("<= parse new session ticket"));
return 0;
}
#endif /* MBEDTLS_SSL_SESSION_TICKETS */
/*
* SSL handshake -- client side -- single step
*/
int mbedtls_ssl_handshake_client_step(mbedtls_ssl_context *ssl)
{
int ret = 0;
if (ssl->state == MBEDTLS_SSL_HANDSHAKE_OVER || ssl->handshake == NULL) {
return MBEDTLS_ERR_SSL_BAD_INPUT_DATA;
}
MBEDTLS_SSL_DEBUG_MSG(2, ("client state: %d", ssl->state));
if ((ret = mbedtls_ssl_flush_output(ssl)) != 0) {
return ret;
}
#if defined(MBEDTLS_SSL_PROTO_DTLS)
if (ssl->conf->transport == MBEDTLS_SSL_TRANSPORT_DATAGRAM &&
ssl->handshake->retransmit_state == MBEDTLS_SSL_RETRANS_SENDING) {
if ((ret = mbedtls_ssl_flight_transmit(ssl)) != 0) {
return ret;
}
}
#endif /* MBEDTLS_SSL_PROTO_DTLS */
/* Change state now, so that it is right in mbedtls_ssl_read_record(), used
* by DTLS for dropping out-of-sequence ChangeCipherSpec records */
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
if (ssl->state == MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC &&
ssl->handshake->new_session_ticket != 0) {
ssl->state = MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET;
}
#endif
switch (ssl->state) {
case MBEDTLS_SSL_HELLO_REQUEST:
ssl->state = MBEDTLS_SSL_CLIENT_HELLO;
break;
/*
* ==> ClientHello
*/
case MBEDTLS_SSL_CLIENT_HELLO:
ret = ssl_write_client_hello(ssl);
break;
/*
* <== ServerHello
* Certificate
* ( ServerKeyExchange )
* ( CertificateRequest )
* ServerHelloDone
*/
case MBEDTLS_SSL_SERVER_HELLO:
ret = ssl_parse_server_hello(ssl);
break;
case MBEDTLS_SSL_SERVER_CERTIFICATE:
ret = mbedtls_ssl_parse_certificate(ssl);
break;
case MBEDTLS_SSL_SERVER_KEY_EXCHANGE:
ret = ssl_parse_server_key_exchange(ssl);
break;
case MBEDTLS_SSL_CERTIFICATE_REQUEST:
ret = ssl_parse_certificate_request(ssl);
break;
case MBEDTLS_SSL_SERVER_HELLO_DONE:
ret = ssl_parse_server_hello_done(ssl);
break;
/*
* ==> ( Certificate/Alert )
* ClientKeyExchange
* ( CertificateVerify )
* ChangeCipherSpec
* Finished
*/
case MBEDTLS_SSL_CLIENT_CERTIFICATE:
ret = mbedtls_ssl_write_certificate(ssl);
break;
case MBEDTLS_SSL_CLIENT_KEY_EXCHANGE:
ret = ssl_write_client_key_exchange(ssl);
break;
case MBEDTLS_SSL_CERTIFICATE_VERIFY:
ret = ssl_write_certificate_verify(ssl);
break;
case MBEDTLS_SSL_CLIENT_CHANGE_CIPHER_SPEC:
ret = mbedtls_ssl_write_change_cipher_spec(ssl);
break;
case MBEDTLS_SSL_CLIENT_FINISHED:
ret = mbedtls_ssl_write_finished(ssl);
break;
/*
* <== ( NewSessionTicket )
* ChangeCipherSpec
* Finished
*/
#if defined(MBEDTLS_SSL_SESSION_TICKETS)
case MBEDTLS_SSL_SERVER_NEW_SESSION_TICKET:
ret = ssl_parse_new_session_ticket(ssl);
break;
#endif
case MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC:
ret = mbedtls_ssl_parse_change_cipher_spec(ssl);
break;
case MBEDTLS_SSL_SERVER_FINISHED:
ret = mbedtls_ssl_parse_finished(ssl);
break;
case MBEDTLS_SSL_FLUSH_BUFFERS:
MBEDTLS_SSL_DEBUG_MSG(2, ("handshake: done"));
ssl->state = MBEDTLS_SSL_HANDSHAKE_WRAPUP;
break;
case MBEDTLS_SSL_HANDSHAKE_WRAPUP:
mbedtls_ssl_handshake_wrapup(ssl);
break;
default:
MBEDTLS_SSL_DEBUG_MSG(1, ("invalid state %d", ssl->state));
return MBEDTLS_ERR_SSL_BAD_INPUT_DATA;
}
return ret;
}
#endif /* MBEDTLS_SSL_CLI_C */