diff options
Diffstat (limited to 'thirdparty/mbedtls/library/ssl_tls12_client.c')
| -rw-r--r-- | thirdparty/mbedtls/library/ssl_tls12_client.c | 3601 |
1 files changed, 3601 insertions, 0 deletions
diff --git a/thirdparty/mbedtls/library/ssl_tls12_client.c b/thirdparty/mbedtls/library/ssl_tls12_client.c new file mode 100644 index 0000000000..eac6a3aadd --- /dev/null +++ b/thirdparty/mbedtls/library/ssl_tls12_client.c @@ -0,0 +1,3601 @@ +/* + * TLS 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) && defined(MBEDTLS_SSL_PROTO_TLS1_2) + +#include "mbedtls/platform.h" + +#include "mbedtls/ssl.h" +#include "ssl_client.h" +#include "ssl_misc.h" +#include "debug_internal.h" +#include "mbedtls/error.h" +#include "mbedtls/constant_time.h" + +#if defined(MBEDTLS_USE_PSA_CRYPTO) +#include "psa_util_internal.h" +#include "psa/crypto.h" +#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) +/* Define a local translating function to save code size by not using too many + * arguments in each translating place. */ +static int local_err_translation(psa_status_t status) +{ + return psa_status_to_mbedtls(status, psa_to_ssl_errors, + ARRAY_LENGTH(psa_to_ssl_errors), + psa_generic_status_to_mbedtls); +} +#define PSA_TO_MBEDTLS_ERR(status) local_err_translation(status) +#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */ +#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_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 */ + +#if defined(MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_1_2_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDSA_CERT_REQ_ALLOWED_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + +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_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_1_2_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDSA_CERT_REQ_ALLOWED_ENABLED || + 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 = 0; + + *olen = 0; + + /* Skip costly extension if we can't use EC J-PAKE anyway */ +#if defined(MBEDTLS_USE_PSA_CRYPTO) + if (ssl->handshake->psa_pake_ctx_is_ok != 1) { + return 0; + } +#else + if (mbedtls_ecjpake_check(&ssl->handshake->ecjpake_ctx) != 0) { + return 0; + } +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + + 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")); + +#if defined(MBEDTLS_USE_PSA_CRYPTO) + ret = mbedtls_psa_ecjpake_write_round(&ssl->handshake->psa_pake_ctx, + p + 2, end - p - 2, &kkpp_len, + MBEDTLS_ECJPAKE_ROUND_ONE); + if (ret != 0) { + psa_destroy_key(ssl->handshake->psa_pake_password); + psa_pake_abort(&ssl->handshake->psa_pake_ctx); + MBEDTLS_SSL_DEBUG_RET(1, "psa_pake_output", ret); + return ret; + } +#else + 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; + } +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + + 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; + + /* + * 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_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) { + 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) { + 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_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 */ + +int mbedtls_ssl_tls12_write_client_hello_exts(mbedtls_ssl_context *ssl, + unsigned char *buf, + const unsigned char *end, + int uses_ec, + size_t *out_len) +{ + int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; + unsigned char *p = buf; + size_t ext_len = 0; + + (void) ssl; + (void) end; + (void) uses_ec; + (void) ret; + (void) ext_len; + + *out_len = 0; + + /* 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, end, &ext_len)) != 0) { + MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_renegotiation_ext", ret); + return ret; + } + p += ext_len; +#endif + +#if defined(MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_1_2_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDSA_CERT_REQ_ALLOWED_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + if (uses_ec) { + if ((ret = ssl_write_supported_point_formats_ext(ssl, p, end, + &ext_len)) != 0) { + MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_supported_point_formats_ext", ret); + return ret; + } + p += ext_len; + } +#endif + +#if defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + if ((ret = ssl_write_ecjpake_kkpp_ext(ssl, p, end, &ext_len)) != 0) { + MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_ecjpake_kkpp_ext", ret); + return ret; + } + p += ext_len; +#endif + +#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) + if ((ret = ssl_write_cid_ext(ssl, p, end, &ext_len)) != 0) { + MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_cid_ext", ret); + return ret; + } + p += ext_len; +#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */ + +#if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH) + if ((ret = ssl_write_max_fragment_length_ext(ssl, p, end, + &ext_len)) != 0) { + MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_max_fragment_length_ext", ret); + return ret; + } + p += ext_len; +#endif + +#if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) + if ((ret = ssl_write_encrypt_then_mac_ext(ssl, p, end, &ext_len)) != 0) { + MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_encrypt_then_mac_ext", ret); + return ret; + } + p += ext_len; +#endif + +#if defined(MBEDTLS_SSL_EXTENDED_MASTER_SECRET) + if ((ret = ssl_write_extended_ms_ext(ssl, p, end, &ext_len)) != 0) { + MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_extended_ms_ext", ret); + return ret; + } + p += ext_len; +#endif + +#if defined(MBEDTLS_SSL_DTLS_SRTP) + if ((ret = ssl_write_use_srtp_ext(ssl, p, end, &ext_len)) != 0) { + MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_use_srtp_ext", ret); + return ret; + } + p += ext_len; +#endif + +#if defined(MBEDTLS_SSL_SESSION_TICKETS) + if ((ret = ssl_write_session_ticket_ext(ssl, p, end, &ext_len)) != 0) { + MBEDTLS_SSL_DEBUG_RET(1, "ssl_write_session_ticket_ext", ret); + return ret; + } + p += ext_len; +#endif + + *out_len = (size_t) (p - buf); + + 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_HANDSHAKE_FAILURE; + } + } 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_HANDSHAKE_FAILURE; + } + + 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_ILLEGAL_PARAMETER; + } + + return 0; +} +#endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */ + +#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_UNSUPPORTED_EXTENSION; + } + + 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_DECODE_ERROR); + return MBEDTLS_ERR_SSL_DECODE_ERROR; + } + + 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_ILLEGAL_PARAMETER); + return MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER; + } + + 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_DECODE_ERROR); + return MBEDTLS_ERR_SSL_DECODE_ERROR; + } + + 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 || + 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_UNSUPPORTED_EXTENSION; + } + + ((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 || + 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_UNSUPPORTED_EXTENSION; + } + + ((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_UNSUPPORTED_EXTENSION; + } + + ((void) buf); + + ssl->handshake->new_session_ticket = 1; + + return 0; +} +#endif /* MBEDTLS_SSL_SESSION_TICKETS */ + +#if defined(MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_1_2_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDSA_CERT_REQ_ALLOWED_ENABLED) || \ + 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_DECODE_ERROR; + } + 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_USE_PSA_CRYPTO) && \ + defined(MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_1_2_ENABLED) + ssl->handshake->ecdh_ctx.point_format = p[0]; +#endif /* !MBEDTLS_USE_PSA_CRYPTO && MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_1_2_ENABLED */ +#if !defined(MBEDTLS_USE_PSA_CRYPTO) && \ + defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED) + mbedtls_ecjpake_set_point_format(&ssl->handshake->ecjpake_ctx, + p[0]); +#endif /* !MBEDTLS_USE_PSA_CRYPTO && MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */ + 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_HANDSHAKE_FAILURE; +} +#endif /* MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_1_2_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDSA_CERT_REQ_ALLOWED_ENABLED || + 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 defined(MBEDTLS_USE_PSA_CRYPTO) + if ((ret = mbedtls_psa_ecjpake_read_round( + &ssl->handshake->psa_pake_ctx, buf, len, + MBEDTLS_ECJPAKE_ROUND_ONE)) != 0) { + psa_destroy_key(ssl->handshake->psa_pake_password); + psa_pake_abort(&ssl->handshake->psa_pake_ctx); + + MBEDTLS_SSL_DEBUG_RET(1, "psa_pake_input round one", ret); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE); + return ret; + } + + return 0; +#else + 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_USE_PSA_CRYPTO */ +} +#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_UNSUPPORTED_EXTENSION; + } + + /* + * 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_DECODE_ERROR; + } + + list_len = MBEDTLS_GET_UINT16_BE(buf, 0); + 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_DECODE_ERROR; + } + + 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_DECODE_ERROR; + } + + /* 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_HANDSHAKE_FAILURE; +} +#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_DECODE_ERROR; + } + + /* + * 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_DECODE_ERROR; + } + + 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_HANDSHAKE_FAILURE; + } + + /* 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_ILLEGAL_PARAMETER; + } +#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) +{ + int ret = MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE; + const unsigned char *p = ssl->in_msg + mbedtls_ssl_hs_hdr_len(ssl); + uint16_t dtls_legacy_version; + +#if !defined(MBEDTLS_SSL_PROTO_TLS1_3) + uint8_t cookie_len; +#else + uint16_t cookie_len; +#endif + + 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_DECODE_ERROR; + } + + /* + * struct { + * ProtocolVersion server_version; + * opaque cookie<0..2^8-1>; + * } HelloVerifyRequest; + */ + MBEDTLS_SSL_DEBUG_BUF(3, "server version", p, 2); + dtls_legacy_version = MBEDTLS_GET_UINT16_BE(p, 0); + p += 2; + + /* + * Since the RFC is not clear on this point, accept DTLS 1.0 (0xfeff) + * The DTLS 1.3 (current draft) renames ProtocolVersion server_version to + * legacy_version and locks the value of legacy_version to 0xfefd (DTLS 1.2) + */ + if (dtls_legacy_version != 0xfefd && dtls_legacy_version != 0xfeff) { + 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_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_DECODE_ERROR; + } + MBEDTLS_SSL_DEBUG_BUF(3, "cookie", p, cookie_len); + + mbedtls_free(ssl->handshake->cookie); + + ssl->handshake->cookie = mbedtls_calloc(1, cookie_len); + if (ssl->handshake->cookie == NULL) { + MBEDTLS_SSL_DEBUG_MSG(1, ("alloc failed (%d bytes)", cookie_len)); + return MBEDTLS_ERR_SSL_ALLOC_FAILED; + } + + memcpy(ssl->handshake->cookie, p, cookie_len); + ssl->handshake->cookie_len = cookie_len; + + /* Start over at ClientHello */ + ssl->state = MBEDTLS_SSL_CLIENT_HELLO; + ret = mbedtls_ssl_reset_checksum(ssl); + if (0 != ret) { + MBEDTLS_SSL_DEBUG_RET(1, ("mbedtls_ssl_reset_checksum"), ret); + return ret; + } + + mbedtls_ssl_recv_flight_completed(ssl); + + MBEDTLS_SSL_DEBUG_MSG(2, ("<= parse hello verify request")); + + return 0; +} +#endif /* MBEDTLS_SSL_PROTO_DTLS */ + +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->cookie); + ssl->handshake->cookie = NULL; + ssl->handshake->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_DECODE_ERROR; + } + + /* + * 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, 2); + ssl->tls_version = (mbedtls_ssl_protocol_version) mbedtls_ssl_read_version(buf, + ssl->conf->transport); + ssl->session_negotiate->tls_version = ssl->tls_version; + ssl->session_negotiate->endpoint = ssl->conf->endpoint; + + if (ssl->tls_version < ssl->conf->min_tls_version || + ssl->tls_version > ssl->conf->max_tls_version) { + MBEDTLS_SSL_DEBUG_MSG(1, + ( + "server version out of bounds - min: [0x%x], server: [0x%x], max: [0x%x]", + (unsigned) ssl->conf->min_tls_version, + (unsigned) ssl->tls_version, + (unsigned) ssl->conf->max_tls_version)); + + mbedtls_ssl_send_alert_message(ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_PROTOCOL_VERSION); + + return MBEDTLS_ERR_SSL_BAD_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_DECODE_ERROR; + } + + if (ssl->in_hslen > mbedtls_ssl_hs_hdr_len(ssl) + 39 + n) { + ext_len = MBEDTLS_GET_UINT16_BE(buf, 38 + 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_DECODE_ERROR; + } + } 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_DECODE_ERROR; + } + + /* ciphersuite (used later) */ + i = (int) MBEDTLS_GET_UINT16_BE(buf, n + 35); + + /* + * Read and check compression + */ + comp = buf[37 + n]; + + if (comp != MBEDTLS_SSL_COMPRESS_NULL) { + 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->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->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[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_ILLEGAL_PARAMETER; + } + + if (ssl->conf->ciphersuite_list[i++] == + ssl->session_negotiate->ciphersuite) { + break; + } + } + + suite_info = mbedtls_ssl_ciphersuite_from_id( + ssl->session_negotiate->ciphersuite); + if (mbedtls_ssl_validate_ciphersuite(ssl, suite_info, ssl->tls_version, + ssl->tls_version) != 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_HANDSHAKE_FAILURE); + return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE; + } + + 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->tls_version == MBEDTLS_SSL_VERSION_TLS1_2) { + ssl->handshake->ecrs_enabled = 1; + } +#endif + + if (comp != MBEDTLS_SSL_COMPRESS_NULL) { + 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_ILLEGAL_PARAMETER; + } + + 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 = MBEDTLS_GET_UINT16_BE(ext, 0); + unsigned int ext_size = MBEDTLS_GET_UINT16_BE(ext, 2); + + 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_DECODE_ERROR; + } + + 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_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_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_1_2_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDSA_CERT_REQ_ALLOWED_ENABLED) || \ + 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_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_1_2_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDSA_CERT_REQ_ALLOWED_ENABLED || + 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_DECODE_ERROR; + } + } + + /* + * 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_HANDSHAKE_FAILURE; + } + + 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_dhm_get_bitlen(&ssl->handshake->dhm_ctx); + 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_HANDSHAKE_FAILURE; + } + + 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_USE_PSA_CRYPTO) +#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) +MBEDTLS_CHECK_RETURN_CRITICAL +static int ssl_parse_server_ecdh_params(mbedtls_ssl_context *ssl, + unsigned char **p, + unsigned char *end) +{ + uint16_t tls_id; + size_t ecpoint_len; + mbedtls_ssl_handshake_params *handshake = ssl->handshake; + psa_key_type_t key_type = PSA_KEY_TYPE_NONE; + size_t ec_bits = 0; + + /* + * struct { + * ECParameters curve_params; + * ECPoint public; + * } ServerECDHParams; + * + * 1 curve_type (must be "named_curve") + * 2..3 NamedCurve + * 4 ECPoint.len + * 5+ ECPoint contents + */ + if (end - *p < 4) { + return MBEDTLS_ERR_SSL_DECODE_ERROR; + } + + /* First byte is curve_type; only named_curve is handled */ + if (*(*p)++ != MBEDTLS_ECP_TLS_NAMED_CURVE) { + return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE; + } + + /* Next two bytes are the namedcurve value */ + tls_id = MBEDTLS_GET_UINT16_BE(*p, 0); + *p += 2; + + /* Check it's a curve we offered */ + if (mbedtls_ssl_check_curve_tls_id(ssl, tls_id) != 0) { + MBEDTLS_SSL_DEBUG_MSG(2, + ("bad server key exchange message (ECDHE curve): %u", + (unsigned) tls_id)); + return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE; + } + + /* Convert EC's TLS ID to PSA key type. */ + if (mbedtls_ssl_get_psa_curve_info_from_tls_id(tls_id, &key_type, + &ec_bits) == PSA_ERROR_NOT_SUPPORTED) { + return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE; + } + handshake->xxdh_psa_type = key_type; + handshake->xxdh_psa_bits = ec_bits; + + /* Keep a copy of the peer's public key */ + ecpoint_len = *(*p)++; + if ((size_t) (end - *p) < ecpoint_len) { + return MBEDTLS_ERR_SSL_DECODE_ERROR; + } + + if (ecpoint_len > sizeof(handshake->xxdh_psa_peerkey)) { + return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE; + } + + memcpy(handshake->xxdh_psa_peerkey, *p, ecpoint_len); + handshake->xxdh_psa_peerkey_len = ecpoint_len; + *p += ecpoint_len; + + return 0; +} +#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */ +#else +#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDH_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED) +MBEDTLS_CHECK_RETURN_CRITICAL +static int ssl_check_server_ecdh_params(const mbedtls_ssl_context *ssl) +{ + uint16_t tls_id; + 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 + + tls_id = mbedtls_ssl_get_tls_id_from_ecp_group_id(grp_id); + if (tls_id == 0) { + MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen")); + return MBEDTLS_ERR_SSL_INTERNAL_ERROR; + } + + MBEDTLS_SSL_DEBUG_MSG(2, ("ECDH curve: %s", + mbedtls_ssl_get_curve_name_from_tls_id(tls_id))); + + if (mbedtls_ssl_check_curve(ssl, grp_id) != 0) { + return -1; + } + + 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_ECDH_RSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED || + MBEDTLS_KEY_EXCHANGE_ECDH_ECDSA_ENABLED */ + +#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) || \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_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_HANDSHAKE_FAILURE; + } + + return ret; +} +#endif /* MBEDTLS_KEY_EXCHANGE_ECDHE_RSA_ENABLED || \ + MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED || \ + MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED */ +#endif /* !MBEDTLS_USE_PSA_CRYPTO */ +#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_DECODE_ERROR; + } + len = MBEDTLS_GET_UINT16_BE(*p, 0); + *p += 2; + + if (end - (*p) < len) { + MBEDTLS_SSL_DEBUG_MSG(1, + ("bad server key exchange message (psk_identity_hint length)")); + return MBEDTLS_ERR_SSL_DECODE_ERROR; + } + + /* + * 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 = 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(p, ssl->conf->transport, + MBEDTLS_SSL_VERSION_TLS1_2); + + 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 (len_bytes == 2) { + MBEDTLS_PUT_UINT16_BE(*olen, ssl->out_msg, offset); + *olen += 2; + } + +#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_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; + 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; + } + +#if !defined(MBEDTLS_PK_USE_PSA_EC_DATA) + const mbedtls_ecp_keypair *peer_key = mbedtls_pk_ec_ro(*peer_pk); +#endif /* !defined(MBEDTLS_PK_USE_PSA_EC_DATA) */ + +#if defined(MBEDTLS_USE_PSA_CRYPTO) + uint16_t tls_id = 0; + psa_key_type_t key_type = PSA_KEY_TYPE_NONE; + mbedtls_ecp_group_id grp_id = mbedtls_pk_get_ec_group_id(peer_pk); + + if (mbedtls_ssl_check_curve(ssl, grp_id) != 0) { + MBEDTLS_SSL_DEBUG_MSG(1, ("bad server certificate (ECDH curve)")); + return MBEDTLS_ERR_SSL_BAD_CERTIFICATE; + } + + tls_id = mbedtls_ssl_get_tls_id_from_ecp_group_id(grp_id); + if (tls_id == 0) { + MBEDTLS_SSL_DEBUG_MSG(1, ("ECC group %u not suported", + grp_id)); + return MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER; + } + + /* If the above conversion to TLS ID was fine, then also this one will be, + so there is no need to check the return value here */ + mbedtls_ssl_get_psa_curve_info_from_tls_id(tls_id, &key_type, + &ssl->handshake->xxdh_psa_bits); + + ssl->handshake->xxdh_psa_type = key_type; + + /* Store peer's public key in psa format. */ +#if defined(MBEDTLS_PK_USE_PSA_EC_DATA) + memcpy(ssl->handshake->xxdh_psa_peerkey, peer_pk->pub_raw, peer_pk->pub_raw_len); + ssl->handshake->xxdh_psa_peerkey_len = peer_pk->pub_raw_len; + ret = 0; +#else /* MBEDTLS_PK_USE_PSA_EC_DATA */ + size_t olen = 0; + ret = mbedtls_ecp_point_write_binary(&peer_key->grp, &peer_key->Q, + MBEDTLS_ECP_PF_UNCOMPRESSED, &olen, + ssl->handshake->xxdh_psa_peerkey, + sizeof(ssl->handshake->xxdh_psa_peerkey)); + + if (ret != 0) { + MBEDTLS_SSL_DEBUG_RET(1, ("mbedtls_ecp_point_write_binary"), ret); + return ret; + } + ssl->handshake->xxdh_psa_peerkey_len = olen; +#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */ +#else /* MBEDTLS_USE_PSA_CRYPTO */ + 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_CERTIFICATE; + } +#endif /* MBEDTLS_USE_PSA_CRYPTO */ +#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, (size_t) (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_DECODE_ERROR); + return MBEDTLS_ERR_SSL_DECODE_ERROR; + } + } /* 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_ILLEGAL_PARAMETER; + } + } else +#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_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_ILLEGAL_PARAMETER; + } + } 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) { +#if defined(MBEDTLS_USE_PSA_CRYPTO) + /* + * The first 3 bytes are: + * [0] MBEDTLS_ECP_TLS_NAMED_CURVE + * [1, 2] elliptic curve's TLS ID + * + * However since we only support secp256r1 for now, we check only + * that TLS ID here + */ + uint16_t read_tls_id = MBEDTLS_GET_UINT16_BE(p, 1); + uint16_t exp_tls_id = mbedtls_ssl_get_tls_id_from_ecp_group_id( + MBEDTLS_ECP_DP_SECP256R1); + + if (exp_tls_id == 0) { + return MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE; + } + + if ((*p != MBEDTLS_ECP_TLS_NAMED_CURVE) || + (read_tls_id != exp_tls_id)) { + return MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER; + } + + p += 3; + + if ((ret = mbedtls_psa_ecjpake_read_round( + &ssl->handshake->psa_pake_ctx, p, end - p, + MBEDTLS_ECJPAKE_ROUND_TWO)) != 0) { + psa_destroy_key(ssl->handshake->psa_pake_password); + psa_pake_abort(&ssl->handshake->psa_pake_ctx); + + MBEDTLS_SSL_DEBUG_RET(1, "psa_pake_input round two", ret); + mbedtls_ssl_send_alert_message( + ssl, + MBEDTLS_SSL_ALERT_LEVEL_FATAL, + MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE); + return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE; + } +#else + 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_HANDSHAKE_FAILURE); + return MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE; + } +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + } 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; + unsigned char hash[MBEDTLS_MD_MAX_SIZE]; + + 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 = (size_t) (p - params); + void *rs_ctx = NULL; + uint16_t sig_alg; + + 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 */ + + /* + * Handle the digitally-signed structure + */ + MBEDTLS_SSL_CHK_BUF_READ_PTR(p, end, 2); + sig_alg = MBEDTLS_GET_UINT16_BE(p, 0); + if (mbedtls_ssl_get_pk_type_and_md_alg_from_sig_alg( + sig_alg, &pk_alg, &md_alg) != 0 && + !mbedtls_ssl_sig_alg_is_offered(ssl, sig_alg) && + !mbedtls_ssl_sig_alg_is_supported(ssl, sig_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_ILLEGAL_PARAMETER); + return MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER; + } + p += 2; + + 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_ILLEGAL_PARAMETER); + return MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER; + } + + /* + * 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_DECODE_ERROR; + } + sig_len = MBEDTLS_GET_UINT16_BE(p, 0); + 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_DECODE_ERROR; + } + + MBEDTLS_SSL_DEBUG_BUF(3, "signature", p, sig_len); + + /* + * Compute the hash that has been signed + */ + 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 { + MBEDTLS_SSL_DEBUG_MSG(1, ("should never happen")); + return MBEDTLS_ERR_SSL_INTERNAL_ERROR; + } + + MBEDTLS_SSL_DEBUG_BUF(3, "parameters hash", hash, hashlen); + + /* + * 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 + +#if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT) + if (pk_alg == MBEDTLS_PK_RSASSA_PSS) { + mbedtls_pk_rsassa_pss_options rsassa_pss_options; + rsassa_pss_options.mgf1_hash_id = md_alg; + rsassa_pss_options.expected_salt_len = + mbedtls_md_get_size_from_type(md_alg); + if (rsassa_pss_options.expected_salt_len == 0) { + return MBEDTLS_ERR_SSL_INTERNAL_ERROR; + } + + ret = mbedtls_pk_verify_ext(pk_alg, &rsassa_pss_options, + peer_pk, + md_alg, hash, hashlen, + p, sig_len); + } else +#endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */ + ret = mbedtls_pk_verify_restartable(peer_pk, + md_alg, hash, hashlen, p, sig_len, rs_ctx); + + if (ret != 0) { + int send_alert_msg = 1; +#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED) + send_alert_msg = (ret != MBEDTLS_ERR_ECP_IN_PROGRESS); +#endif + if (send_alert_msg) { + 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); +#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 !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; + size_t sig_alg_len; +#if defined(MBEDTLS_DEBUG_C) + unsigned char *sig_alg; + unsigned char *dn; +#endif + + 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->handshake->client_auth = + (ssl->in_msg[0] == MBEDTLS_SSL_HS_CERTIFICATE_REQUEST); + + MBEDTLS_SSL_DEBUG_MSG(3, ("got %s certificate request", + ssl->handshake->client_auth ? "a" : "no")); + + if (ssl->handshake->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_DECODE_ERROR; + } + 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_DECODE_ERROR; + } + + /* supported_signature_algorithms */ + sig_alg_len = MBEDTLS_GET_UINT16_BE(buf, mbedtls_ssl_hs_hdr_len(ssl) + 1 + n); + + /* + * 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_DECODE_ERROR; + } + +#if defined(MBEDTLS_DEBUG_C) + sig_alg = buf + mbedtls_ssl_hs_hdr_len(ssl) + 3 + n; + for (size_t i = 0; i < sig_alg_len; i += 2) { + MBEDTLS_SSL_DEBUG_MSG(3, + ("Supported Signature Algorithm found: %02x %02x", + sig_alg[i], sig_alg[i + 1])); + } +#endif + + n += 2 + sig_alg_len; + + /* certificate_authorities */ + dn_len = MBEDTLS_GET_UINT16_BE(buf, mbedtls_ssl_hs_hdr_len(ssl) + 1 + 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_DECODE_ERROR; + } + +#if defined(MBEDTLS_DEBUG_C) + dn = buf + mbedtls_ssl_hs_hdr_len(ssl) + 3 + n - dn_len; + for (size_t i = 0, dni_len = 0; i < dn_len; i += 2 + dni_len) { + unsigned char *p = dn + i + 2; + mbedtls_x509_name name; + size_t asn1_len; + char s[MBEDTLS_X509_MAX_DN_NAME_SIZE]; + memset(&name, 0, sizeof(name)); + dni_len = MBEDTLS_GET_UINT16_BE(dn + i, 0); + if (dni_len > dn_len - i - 2 || + mbedtls_asn1_get_tag(&p, p + dni_len, &asn1_len, + MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE) != 0 || + mbedtls_x509_get_name(&p, p + asn1_len, &name) != 0) { + 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_DECODE_ERROR; + } + MBEDTLS_SSL_DEBUG_MSG(3, + ("DN hint: %.*s", + mbedtls_x509_dn_gets(s, sizeof(s), &name), s)); + mbedtls_asn1_free_named_data_list_shallow(name.next); + } +#endif + +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_DECODE_ERROR; + } + + 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 = mbedtls_dhm_get_len(&ssl->handshake->dhm_ctx); + + MBEDTLS_PUT_UINT16_BE(content_len, ssl->out_msg, 4); + header_len = 6; + + ret = mbedtls_dhm_make_public(&ssl->handshake->dhm_ctx, + (int) mbedtls_dhm_get_len(&ssl->handshake->dhm_ctx), + &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_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) { +#if defined(MBEDTLS_USE_PSA_CRYPTO) + 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; + + 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->xxdh_psa_type); + psa_set_key_bits(&key_attributes, handshake->xxdh_psa_bits); + + /* Generate ECDH private key. */ + status = psa_generate_key(&key_attributes, + &handshake->xxdh_psa_privkey); + if (status != PSA_SUCCESS) { + return MBEDTLS_ERR_SSL_HW_ACCEL_FAILED; + } + + /* Export the public part of the ECDH private key from PSA. + * The export format is an ECPoint structure as expected by TLS, + * but we just need to add a length byte before that. */ + unsigned char *own_pubkey = ssl->out_msg + header_len + 1; + unsigned char *end = ssl->out_msg + MBEDTLS_SSL_OUT_CONTENT_LEN; + size_t own_pubkey_max_len = (size_t) (end - own_pubkey); + size_t own_pubkey_len; + + status = psa_export_public_key(handshake->xxdh_psa_privkey, + own_pubkey, own_pubkey_max_len, + &own_pubkey_len); + if (status != PSA_SUCCESS) { + psa_destroy_key(handshake->xxdh_psa_privkey); + handshake->xxdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT; + return MBEDTLS_ERR_SSL_HW_ACCEL_FAILED; + } + + ssl->out_msg[header_len] = (unsigned char) own_pubkey_len; + content_len = own_pubkey_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->xxdh_psa_privkey, + handshake->xxdh_psa_peerkey, + handshake->xxdh_psa_peerkey_len, + ssl->handshake->premaster, + sizeof(ssl->handshake->premaster), + &ssl->handshake->pmslen); + + destruction_status = psa_destroy_key(handshake->xxdh_psa_privkey); + handshake->xxdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT; + + if (status != PSA_SUCCESS || destruction_status != PSA_SUCCESS) { + return MBEDTLS_ERR_SSL_HW_ACCEL_FAILED; + } +#else + /* + * 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); +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + } 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_USE_PSA_CRYPTO) && \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) + if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK) { + 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; + + /* + * opaque psk_identity<0..2^16-1>; + */ + if (mbedtls_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; + } + + /* uint16 to store content length */ + const size_t content_len_size = 2; + + header_len = 4; + + if (header_len + content_len_size + ssl->conf->psk_identity_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; + } + + unsigned char *p = ssl->out_msg + header_len; + + *p++ = MBEDTLS_BYTE_1(ssl->conf->psk_identity_len); + *p++ = MBEDTLS_BYTE_0(ssl->conf->psk_identity_len); + header_len += content_len_size; + + memcpy(p, ssl->conf->psk_identity, + ssl->conf->psk_identity_len); + p += ssl->conf->psk_identity_len; + + header_len += ssl->conf->psk_identity_len; + + 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->xxdh_psa_type); + psa_set_key_bits(&key_attributes, handshake->xxdh_psa_bits); + + /* Generate ECDH private key. */ + status = psa_generate_key(&key_attributes, + &handshake->xxdh_psa_privkey); + if (status != PSA_SUCCESS) { + return PSA_TO_MBEDTLS_ERR(status); + } + + /* Export the public part of the ECDH private key from PSA. + * The export format is an ECPoint structure as expected by TLS, + * but we just need to add a length byte before that. */ + unsigned char *own_pubkey = p + 1; + unsigned char *end = ssl->out_msg + MBEDTLS_SSL_OUT_CONTENT_LEN; + size_t own_pubkey_max_len = (size_t) (end - own_pubkey); + size_t own_pubkey_len = 0; + + status = psa_export_public_key(handshake->xxdh_psa_privkey, + own_pubkey, own_pubkey_max_len, + &own_pubkey_len); + if (status != PSA_SUCCESS) { + psa_destroy_key(handshake->xxdh_psa_privkey); + handshake->xxdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT; + return PSA_TO_MBEDTLS_ERR(status); + } + + *p = (unsigned char) own_pubkey_len; + content_len = own_pubkey_len + 1; + + /* As RFC 5489 section 2, the premaster secret is formed as follows: + * - a uint16 containing the length (in octets) of the ECDH computation + * - the octet string produced by the ECDH computation + * - a uint16 containing the length (in octets) of the PSK + * - the PSK itself + */ + unsigned char *pms = ssl->handshake->premaster; + const unsigned char * const pms_end = pms + + sizeof(ssl->handshake->premaster); + /* uint16 to store length (in octets) of the ECDH computation */ + const size_t zlen_size = 2; + size_t zlen = 0; + + /* Perform ECDH computation after the uint16 reserved for the length */ + status = psa_raw_key_agreement(PSA_ALG_ECDH, + handshake->xxdh_psa_privkey, + handshake->xxdh_psa_peerkey, + handshake->xxdh_psa_peerkey_len, + pms + zlen_size, + pms_end - (pms + zlen_size), + &zlen); + + destruction_status = psa_destroy_key(handshake->xxdh_psa_privkey); + handshake->xxdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT; + + if (status != PSA_SUCCESS) { + return PSA_TO_MBEDTLS_ERR(status); + } else if (destruction_status != PSA_SUCCESS) { + return PSA_TO_MBEDTLS_ERR(destruction_status); + } + + /* Write the ECDH computation length before the ECDH computation */ + MBEDTLS_PUT_UINT16_BE(zlen, pms, 0); + pms += zlen_size + zlen; + } else +#endif /* MBEDTLS_USE_PSA_CRYPTO && + MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_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 (mbedtls_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 ((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) { + /* + * ClientDiffieHellmanPublic public (DHM send G^X mod P) + */ + content_len = mbedtls_dhm_get_len(&ssl->handshake->dhm_ctx); + + 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_dhm_get_len(&ssl->handshake->dhm_ctx), + &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; + } + +#if defined(MBEDTLS_USE_PSA_CRYPTO) + unsigned char *pms = ssl->handshake->premaster; + unsigned char *pms_end = pms + sizeof(ssl->handshake->premaster); + size_t pms_len; + + /* Write length only when we know the actual value */ + if ((ret = mbedtls_dhm_calc_secret(&ssl->handshake->dhm_ctx, + pms + 2, pms_end - (pms + 2), &pms_len, + ssl->conf->f_rng, ssl->conf->p_rng)) != 0) { + MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_dhm_calc_secret", ret); + return ret; + } + MBEDTLS_PUT_UINT16_BE(pms_len, pms, 0); + pms += 2 + pms_len; + + MBEDTLS_SSL_DEBUG_MPI(3, "DHM: K ", &ssl->handshake->dhm_ctx.K); +#endif + } else +#endif /* MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */ +#if !defined(MBEDTLS_USE_PSA_CRYPTO) && \ + defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED) + if (ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK) { + /* + * 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_USE_PSA_CRYPTO && 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) + if ((ret = mbedtls_ssl_psk_derive_premaster(ssl, + (mbedtls_key_exchange_type_t) ciphersuite_info-> + key_exchange)) != 0) { + MBEDTLS_SSL_DEBUG_RET(1, + "mbedtls_ssl_psk_derive_premaster", ret); + return ret; + } +#endif /* !MBEDTLS_USE_PSA_CRYPTO */ + } 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; + +#if defined(MBEDTLS_USE_PSA_CRYPTO) + unsigned char *out_p = ssl->out_msg + header_len; + unsigned char *end_p = ssl->out_msg + MBEDTLS_SSL_OUT_CONTENT_LEN - + header_len; + ret = mbedtls_psa_ecjpake_write_round(&ssl->handshake->psa_pake_ctx, + out_p, end_p - out_p, &content_len, + MBEDTLS_ECJPAKE_ROUND_TWO); + if (ret != 0) { + psa_destroy_key(ssl->handshake->psa_pake_password); + psa_pake_abort(&ssl->handshake->psa_pake_ctx); + MBEDTLS_SSL_DEBUG_RET(1, "psa_pake_output", ret); + return ret; + } +#else + 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; + } +#endif /* MBEDTLS_USE_PSA_CRYPTO */ + } 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; +#if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH) + size_t out_buf_len = ssl->out_buf_len - (size_t) (ssl->out_msg - ssl->out_buf); +#else + size_t out_buf_len = MBEDTLS_SSL_OUT_BUFFER_LEN - (size_t) (ssl->out_msg - ssl->out_buf); +#endif + + 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->handshake->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 + + ret = ssl->handshake->calc_verify(ssl, hash, &hashlen); + if (0 != ret) { + MBEDTLS_SSL_DEBUG_RET(1, ("calc_verify"), ret); + return ret; + } + + /* + * 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; + +#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, + out_buf_len - 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_DECODE_ERROR; + } + + msg = ssl->in_msg + mbedtls_ssl_hs_hdr_len(ssl); + + lifetime = MBEDTLS_GET_UINT32_BE(msg, 0); + + ticket_len = MBEDTLS_GET_UINT16_BE(msg, 4); + + 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_DECODE_ERROR; + } + + 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_zeroize_and_free(ssl->session->ticket, + ssl->session->ticket_len); + ssl->session->ticket = NULL; + ssl->session->ticket_len = 0; + } + + mbedtls_zeroize_and_free(ssl->session_negotiate->ticket, + ssl->session_negotiate->ticket_len); + 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; + + /* 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_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 = mbedtls_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_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 && MBEDTLS_SSL_PROTO_TLS1_2 */ |