static int test_get_prefixed(void) { static const uint8_t kData[] = {1, 2, 0, 2, 3, 4, 0, 0, 3, 3, 2, 1}; uint8_t u8; uint16_t u16; uint32_t u32; CBS data, prefixed; CBS_init(&data, kData, sizeof(kData)); return CBS_get_u8_length_prefixed(&data, &prefixed) && CBS_len(&prefixed) == 1 && CBS_get_u8(&prefixed, &u8) && u8 == 2 && CBS_get_u16_length_prefixed(&data, &prefixed) && CBS_len(&prefixed) == 2 && CBS_get_u16(&prefixed, &u16) && u16 == 0x304 && CBS_get_u24_length_prefixed(&data, &prefixed) && CBS_len(&prefixed) == 3 && CBS_get_u24(&prefixed, &u32) && u32 == 0x30201; }
static int test_get_prefixed_bad(void) { static const uint8_t kData1[] = {2, 1}; static const uint8_t kData2[] = {0, 2, 1}; static const uint8_t kData3[] = {0, 0, 2, 1}; CBS data, prefixed; CBS_init(&data, kData1, sizeof(kData1)); if (CBS_get_u8_length_prefixed(&data, &prefixed)) { return 0; } CBS_init(&data, kData2, sizeof(kData2)); if (CBS_get_u16_length_prefixed(&data, &prefixed)) { return 0; } CBS_init(&data, kData3, sizeof(kData3)); if (CBS_get_u24_length_prefixed(&data, &prefixed)) { return 0; } return 1; }
STACK_OF(CRYPTO_BUFFER) *ssl_parse_cert_chain(uint8_t *out_alert, EVP_PKEY **out_pubkey, uint8_t *out_leaf_sha256, CBS *cbs, CRYPTO_BUFFER_POOL *pool) { *out_pubkey = NULL; STACK_OF(CRYPTO_BUFFER) *ret = sk_CRYPTO_BUFFER_new_null(); if (ret == NULL) { *out_alert = SSL_AD_INTERNAL_ERROR; OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); return NULL; } CBS certificate_list; if (!CBS_get_u24_length_prefixed(cbs, &certificate_list)) { *out_alert = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); goto err; } while (CBS_len(&certificate_list) > 0) { CBS certificate; if (!CBS_get_u24_length_prefixed(&certificate_list, &certificate) || CBS_len(&certificate) == 0) { *out_alert = SSL_AD_DECODE_ERROR; OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_LENGTH_MISMATCH); goto err; } if (sk_CRYPTO_BUFFER_num(ret) == 0) { *out_pubkey = ssl_cert_parse_pubkey(&certificate); if (*out_pubkey == NULL) { *out_alert = SSL_AD_DECODE_ERROR; goto err; } /* Retain the hash of the leaf certificate if requested. */ if (out_leaf_sha256 != NULL) { SHA256(CBS_data(&certificate), CBS_len(&certificate), out_leaf_sha256); } } CRYPTO_BUFFER *buf = CRYPTO_BUFFER_new_from_CBS(&certificate, pool); if (buf == NULL) { *out_alert = SSL_AD_DECODE_ERROR; goto err; } if (!sk_CRYPTO_BUFFER_push(ret, buf)) { *out_alert = SSL_AD_INTERNAL_ERROR; CRYPTO_BUFFER_free(buf); OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } } return ret; err: EVP_PKEY_free(*out_pubkey); *out_pubkey = NULL; sk_CRYPTO_BUFFER_pop_free(ret, CRYPTO_BUFFER_free); return NULL; }
int tls13_process_certificate(SSL_HANDSHAKE *hs, int allow_anonymous) { SSL *const ssl = hs->ssl; CBS cbs, context, certificate_list; CBS_init(&cbs, ssl->init_msg, ssl->init_num); if (!CBS_get_u8_length_prefixed(&cbs, &context) || CBS_len(&context) != 0) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); return 0; } const int retain_sha256 = ssl->server && ssl->retain_only_sha256_of_client_certs; int ret = 0; EVP_PKEY *pkey = NULL; STACK_OF(CRYPTO_BUFFER) *certs = sk_CRYPTO_BUFFER_new_null(); if (certs == NULL) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } if (!CBS_get_u24_length_prefixed(&cbs, &certificate_list)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); goto err; } while (CBS_len(&certificate_list) > 0) { CBS certificate, extensions; if (!CBS_get_u24_length_prefixed(&certificate_list, &certificate) || !CBS_get_u16_length_prefixed(&certificate_list, &extensions) || CBS_len(&certificate) == 0) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_LENGTH_MISMATCH); goto err; } if (sk_CRYPTO_BUFFER_num(certs) == 0) { pkey = ssl_cert_parse_pubkey(&certificate); if (pkey == NULL) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); goto err; } /* TLS 1.3 always uses certificate keys for signing thus the correct * keyUsage is enforced. */ if (!ssl_cert_check_digital_signature_key_usage(&certificate)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER); goto err; } if (retain_sha256) { /* Retain the hash of the leaf certificate if requested. */ SHA256(CBS_data(&certificate), CBS_len(&certificate), ssl->s3->new_session->peer_sha256); } } CRYPTO_BUFFER *buf = CRYPTO_BUFFER_new_from_CBS(&certificate, ssl->ctx->pool); if (buf == NULL || !sk_CRYPTO_BUFFER_push(certs, buf)) { CRYPTO_BUFFER_free(buf); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE); goto err; } /* Parse out the extensions. */ int have_status_request = 0, have_sct = 0; CBS status_request, sct; const SSL_EXTENSION_TYPE ext_types[] = { {TLSEXT_TYPE_status_request, &have_status_request, &status_request}, {TLSEXT_TYPE_certificate_timestamp, &have_sct, &sct}, }; uint8_t alert; if (!ssl_parse_extensions(&extensions, &alert, ext_types, OPENSSL_ARRAY_SIZE(ext_types), 0 /* reject unknown */)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, alert); goto err; } /* All Certificate extensions are parsed, but only the leaf extensions are * stored. */ if (have_status_request) { if (ssl->server || !ssl->ocsp_stapling_enabled) { OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION); goto err; } uint8_t status_type; CBS ocsp_response; if (!CBS_get_u8(&status_request, &status_type) || status_type != TLSEXT_STATUSTYPE_ocsp || !CBS_get_u24_length_prefixed(&status_request, &ocsp_response) || CBS_len(&ocsp_response) == 0 || CBS_len(&status_request) != 0) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); goto err; } if (sk_CRYPTO_BUFFER_num(certs) == 1 && !CBS_stow(&ocsp_response, &ssl->s3->new_session->ocsp_response, &ssl->s3->new_session->ocsp_response_length)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); goto err; } } if (have_sct) { if (ssl->server || !ssl->signed_cert_timestamps_enabled) { OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION); goto err; } if (!ssl_is_sct_list_valid(&sct)) { OPENSSL_PUT_ERROR(SSL, SSL_R_ERROR_PARSING_EXTENSION); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); goto err; } if (sk_CRYPTO_BUFFER_num(certs) == 1 && !CBS_stow(&sct, &ssl->s3->new_session->tlsext_signed_cert_timestamp_list, &ssl->s3->new_session ->tlsext_signed_cert_timestamp_list_length)) { ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); goto err; } } } if (CBS_len(&cbs) != 0) { OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); goto err; } EVP_PKEY_free(hs->peer_pubkey); hs->peer_pubkey = pkey; pkey = NULL; sk_CRYPTO_BUFFER_pop_free(ssl->s3->new_session->certs, CRYPTO_BUFFER_free); ssl->s3->new_session->certs = certs; certs = NULL; if (!ssl_session_x509_cache_objects(ssl->s3->new_session)) { OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR); goto err; } if (sk_CRYPTO_BUFFER_num(ssl->s3->new_session->certs) == 0) { if (!allow_anonymous) { OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE); ssl3_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_CERTIFICATE_REQUIRED); goto err; } /* OpenSSL returns X509_V_OK when no certificates are requested. This is * classed by them as a bug, but it's assumed by at least NGINX. */ ssl->s3->new_session->verify_result = X509_V_OK; /* No certificate, so nothing more to do. */ ret = 1; goto err; } ssl->s3->new_session->peer_sha256_valid = retain_sha256; if (!ssl_verify_cert_chain(ssl, &ssl->s3->new_session->verify_result, ssl->s3->new_session->x509_chain)) { goto err; } ret = 1; err: sk_CRYPTO_BUFFER_pop_free(certs, CRYPTO_BUFFER_free); EVP_PKEY_free(pkey); return ret; }