kris/boringssl
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
b1b4ff93ca
boringssl/ssl/tls13_both.cc
Jesse Selover d7266ecc9b Enforce key usage for RSA keys in TLS 1.2. 
For now, this is off by default and controlled by SSL_set_enforce_rsa_key_usage.
This may be set as late as certificate verification so we may start by enforcing
it for known roots.

Generalizes ssl_cert_check_digital_signature_key_usage to check any part of the
key_usage, and adds a new error KEY_USAGE_BIT_INCORRECT for the generalized
method.

Bug: chromium:795089
Change-Id: Ifa504c321bec3263a4e74f2dc48513e3b895d3ee
Reviewed-on: https://boringssl-review.googlesource.com/c/34604
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
2019-01-30 21:28:34 +00:00

695 lines
23 KiB
C++
Raw Blame History

/* Copyright (c) 2016, Google Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
#include <openssl/ssl.h>
#include <assert.h>
#include <string.h>
#include <utility>
#include <openssl/bytestring.h>
#include <openssl/err.h>
#include <openssl/hkdf.h>
#include <openssl/mem.h>
#include <openssl/stack.h>
#include <openssl/x509.h>
#include "../crypto/internal.h"
#include "internal.h"
BSSL_NAMESPACE_BEGIN
// kMaxKeyUpdates is the number of consecutive KeyUpdates that will be
// processed. Without this limit an attacker could force unbounded processing
// without being able to return application data.
static const uint8_t kMaxKeyUpdates = 32;
const uint8_t kHelloRetryRequest[SSL3_RANDOM_SIZE] = {
0xcf, 0x21, 0xad, 0x74, 0xe5, 0x9a, 0x61, 0x11, 0xbe, 0x1d, 0x8c,
0x02, 0x1e, 0x65, 0xb8, 0x91, 0xc2, 0xa2, 0x11, 0x16, 0x7a, 0xbb,
0x8c, 0x5e, 0x07, 0x9e, 0x09, 0xe2, 0xc8, 0xa8, 0x33, 0x9c,
};
// See RFC 8446, section 4.1.3.
const uint8_t kTLS12DowngradeRandom[8] = {0x44, 0x4f, 0x57, 0x4e,
0x47, 0x52, 0x44, 0x00};
const uint8_t kTLS13DowngradeRandom[8] = {0x44, 0x4f, 0x57, 0x4e,
0x47, 0x52, 0x44, 0x01};
// This is a non-standard randomly-generated value.
const uint8_t kJDK11DowngradeRandom[8] = {0xed, 0xbf, 0xb4, 0xa8,
0xc2, 0x47, 0x10, 0xff};
bool tls13_get_cert_verify_signature_input(
SSL_HANDSHAKE *hs, Array<uint8_t> *out,
enum ssl_cert_verify_context_t cert_verify_context) {
ScopedCBB cbb;
if (!CBB_init(cbb.get(), 64 + 33 + 1 + 2 * EVP_MAX_MD_SIZE)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return false;
}
for (size_t i = 0; i < 64; i++) {
if (!CBB_add_u8(cbb.get(), 0x20)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return false;
}
}
Span<const char> context;
if (cert_verify_context == ssl_cert_verify_server) {
static const char kContext[] = "TLS 1.3, server CertificateVerify";
context = kContext;
} else if (cert_verify_context == ssl_cert_verify_client) {
static const char kContext[] = "TLS 1.3, client CertificateVerify";
context = kContext;
} else if (cert_verify_context == ssl_cert_verify_channel_id) {
static const char kContext[] = "TLS 1.3, Channel ID";
context = kContext;
} else {
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return false;
}
// Note |context| includes the NUL byte separator.
if (!CBB_add_bytes(cbb.get(),
reinterpret_cast<const uint8_t *>(context.data()),
context.size())) {
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return false;
}
uint8_t context_hash[EVP_MAX_MD_SIZE];
size_t context_hash_len;
if (!hs->transcript.GetHash(context_hash, &context_hash_len) ||
!CBB_add_bytes(cbb.get(), context_hash, context_hash_len) ||
!CBBFinishArray(cbb.get(), out)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return false;
}
return true;
}
bool tls13_process_certificate(SSL_HANDSHAKE *hs, const SSLMessage &msg,
bool allow_anonymous) {
SSL *const ssl = hs->ssl;
CBS body = msg.body;
bssl::UniquePtr<CRYPTO_BUFFER> decompressed;
if (msg.type == SSL3_MT_COMPRESSED_CERTIFICATE) {
CBS compressed;
uint16_t alg_id;
uint32_t uncompressed_len;
if (!CBS_get_u16(&body, &alg_id) ||
!CBS_get_u24(&body, &uncompressed_len) ||
!CBS_get_u24_length_prefixed(&body, &compressed) ||
CBS_len(&body) != 0) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
return false;
}
if (uncompressed_len > ssl->max_cert_list) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
OPENSSL_PUT_ERROR(SSL, SSL_R_UNCOMPRESSED_CERT_TOO_LARGE);
ERR_add_error_dataf("requested=%u",
static_cast<unsigned>(uncompressed_len));
return false;
}
ssl_cert_decompression_func_t decompress = nullptr;
for (const auto* alg : ssl->ctx->cert_compression_algs.get()) {
if (alg->alg_id == alg_id) {
decompress = alg->decompress;
break;
}
}
if (decompress == nullptr) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_CERT_COMPRESSION_ALG);
ERR_add_error_dataf("alg=%d", static_cast<int>(alg_id));
return false;
}
CRYPTO_BUFFER *decompressed_ptr = nullptr;
if (!decompress(ssl, &decompressed_ptr, uncompressed_len,
CBS_data(&compressed), CBS_len(&compressed))) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_DECOMPRESSION_FAILED);
ERR_add_error_dataf("alg=%d", static_cast<int>(alg_id));
return false;
}
decompressed.reset(decompressed_ptr);
if (CRYPTO_BUFFER_len(decompressed_ptr) != uncompressed_len) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_DECOMPRESSION_FAILED);
ERR_add_error_dataf(
"alg=%d got=%u expected=%u", static_cast<int>(alg_id),
static_cast<unsigned>(CRYPTO_BUFFER_len(decompressed_ptr)),
static_cast<unsigned>(uncompressed_len));
return false;
}
CBS_init(&body, CRYPTO_BUFFER_data(decompressed_ptr),
CRYPTO_BUFFER_len(decompressed_ptr));
} else {
assert(msg.type == SSL3_MT_CERTIFICATE);
}
CBS context, certificate_list;
if (!CBS_get_u8_length_prefixed(&body, &context) ||
CBS_len(&context) != 0 ||
!CBS_get_u24_length_prefixed(&body, &certificate_list) ||
CBS_len(&body) != 0) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
return false;
}
UniquePtr<STACK_OF(CRYPTO_BUFFER)> certs(sk_CRYPTO_BUFFER_new_null());
if (!certs) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return false;
}
const bool retain_sha256 =
ssl->server && hs->config->retain_only_sha256_of_client_certs;
UniquePtr<EVP_PKEY> pkey;
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) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_CERT_LENGTH_MISMATCH);
return false;
}
if (sk_CRYPTO_BUFFER_num(certs.get()) == 0) {
pkey = ssl_cert_parse_pubkey(&certificate);
if (!pkey) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
return false;
}
// TLS 1.3 always uses certificate keys for signing thus the correct
// keyUsage is enforced.
if (!ssl_cert_check_key_usage(&certificate,
key_usage_digital_signature)) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
return false;
}
if (retain_sha256) {
// Retain the hash of the leaf certificate if requested.
SHA256(CBS_data(&certificate), CBS_len(&certificate),
hs->new_session->peer_sha256);
}
}
UniquePtr<CRYPTO_BUFFER> buf(
CRYPTO_BUFFER_new_from_CBS(&certificate, ssl->ctx->pool));
if (!buf ||
!PushToStack(certs.get(), std::move(buf))) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
OPENSSL_PUT_ERROR(SSL, ERR_R_MALLOC_FAILURE);
return false;
}
// Parse out the extensions.
bool have_status_request = false, have_sct = false;
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 = SSL_AD_DECODE_ERROR;
if (!ssl_parse_extensions(&extensions, &alert, ext_types,
OPENSSL_ARRAY_SIZE(ext_types),
0 /* reject unknown */)) {
ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
return false;
}
// All Certificate extensions are parsed, but only the leaf extensions are
// stored.
if (have_status_request) {
if (ssl->server || !hs->config->ocsp_stapling_enabled) {
OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION);
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION);
return false;
}
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) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
return false;
}
if (sk_CRYPTO_BUFFER_num(certs.get()) == 1) {
hs->new_session->ocsp_response.reset(
CRYPTO_BUFFER_new_from_CBS(&ocsp_response, ssl->ctx->pool));
if (hs->new_session->ocsp_response == nullptr) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
return false;
}
}
}
if (have_sct) {
if (ssl->server || !hs->config->signed_cert_timestamps_enabled) {
OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_EXTENSION);
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNSUPPORTED_EXTENSION);
return false;
}
if (!ssl_is_sct_list_valid(&sct)) {
OPENSSL_PUT_ERROR(SSL, SSL_R_ERROR_PARSING_EXTENSION);
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
return false;
}
if (sk_CRYPTO_BUFFER_num(certs.get()) == 1) {
hs->new_session->signed_cert_timestamp_list.reset(
CRYPTO_BUFFER_new_from_CBS(&sct, ssl->ctx->pool));
if (hs->new_session->signed_cert_timestamp_list == nullptr) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
return false;
}
}
}
}
// Store a null certificate list rather than an empty one if the peer didn't
// send certificates.
if (sk_CRYPTO_BUFFER_num(certs.get()) == 0) {
certs.reset();
}
hs->peer_pubkey = std::move(pkey);
hs->new_session->certs = std::move(certs);
if (!ssl->ctx->x509_method->session_cache_objects(hs->new_session.get())) {
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
return false;
}
if (sk_CRYPTO_BUFFER_num(hs->new_session->certs.get()) == 0) {
if (!allow_anonymous) {
OPENSSL_PUT_ERROR(SSL, SSL_R_PEER_DID_NOT_RETURN_A_CERTIFICATE);
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_CERTIFICATE_REQUIRED);
return false;
}
// 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.
hs->new_session->verify_result = X509_V_OK;
// No certificate, so nothing more to do.
return true;
}
hs->new_session->peer_sha256_valid = retain_sha256;
return true;
}
bool tls13_process_certificate_verify(SSL_HANDSHAKE *hs, const SSLMessage &msg) {
SSL *const ssl = hs->ssl;
if (hs->peer_pubkey == NULL) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return false;
}
CBS body = msg.body, signature;
uint16_t signature_algorithm;
if (!CBS_get_u16(&body, &signature_algorithm) ||
!CBS_get_u16_length_prefixed(&body, &signature) ||
CBS_len(&body) != 0) {
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
return false;
}
uint8_t alert = SSL_AD_DECODE_ERROR;
if (!tls12_check_peer_sigalg(ssl, &alert, signature_algorithm)) {
ssl_send_alert(ssl, SSL3_AL_FATAL, alert);
return false;
}
hs->new_session->peer_signature_algorithm = signature_algorithm;
Array<uint8_t> input;
if (!tls13_get_cert_verify_signature_input(
hs, &input,
ssl->server ? ssl_cert_verify_client : ssl_cert_verify_server)) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
return false;
}
bool sig_ok = ssl_public_key_verify(ssl, signature, signature_algorithm,
hs->peer_pubkey.get(), input);
#if defined(BORINGSSL_UNSAFE_FUZZER_MODE)
sig_ok = true;
ERR_clear_error();
#endif
if (!sig_ok) {
OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_SIGNATURE);
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR);
return false;
}
return true;
}
bool tls13_process_finished(SSL_HANDSHAKE *hs, const SSLMessage &msg,
bool use_saved_value) {
SSL *const ssl = hs->ssl;
uint8_t verify_data_buf[EVP_MAX_MD_SIZE];
const uint8_t *verify_data;
size_t verify_data_len;
if (use_saved_value) {
assert(ssl->server);
verify_data = hs->expected_client_finished;
verify_data_len = hs->hash_len;
} else {
if (!tls13_finished_mac(hs, verify_data_buf, &verify_data_len,
!ssl->server)) {
return false;
}
verify_data = verify_data_buf;
}
bool finished_ok = CBS_mem_equal(&msg.body, verify_data, verify_data_len);
#if defined(BORINGSSL_UNSAFE_FUZZER_MODE)
finished_ok = true;
#endif
if (!finished_ok) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECRYPT_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_DIGEST_CHECK_FAILED);
return false;
}
return true;
}
bool tls13_add_certificate(SSL_HANDSHAKE *hs) {
SSL *const ssl = hs->ssl;
CERT *const cert = hs->config->cert.get();
DC *const dc = cert->dc.get();
ScopedCBB cbb;
CBB *body, body_storage, certificate_list;
if (hs->cert_compression_negotiated) {
if (!CBB_init(cbb.get(), 1024)) {
return false;
}
body = cbb.get();
} else {
body = &body_storage;
if (!ssl->method->init_message(ssl, cbb.get(), body, SSL3_MT_CERTIFICATE)) {
return false;
}
}
if (// The request context is always empty in the handshake.
!CBB_add_u8(body, 0) ||
!CBB_add_u24_length_prefixed(body, &certificate_list)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return false;
}
if (!ssl_has_certificate(hs)) {
return ssl_add_message_cbb(ssl, cbb.get());
}
CRYPTO_BUFFER *leaf_buf = sk_CRYPTO_BUFFER_value(cert->chain.get(), 0);
CBB leaf, extensions;
if (!CBB_add_u24_length_prefixed(&certificate_list, &leaf) ||
!CBB_add_bytes(&leaf, CRYPTO_BUFFER_data(leaf_buf),
CRYPTO_BUFFER_len(leaf_buf)) ||
!CBB_add_u16_length_prefixed(&certificate_list, &extensions)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return false;
}
if (hs->scts_requested && cert->signed_cert_timestamp_list != nullptr) {
CBB contents;
if (!CBB_add_u16(&extensions, TLSEXT_TYPE_certificate_timestamp) ||
!CBB_add_u16_length_prefixed(&extensions, &contents) ||
!CBB_add_bytes(
&contents,
CRYPTO_BUFFER_data(cert->signed_cert_timestamp_list.get()),
CRYPTO_BUFFER_len(cert->signed_cert_timestamp_list.get())) ||
!CBB_flush(&extensions)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return false;
}
}
if (hs->ocsp_stapling_requested && cert->ocsp_response != NULL) {
CBB contents, ocsp_response;
if (!CBB_add_u16(&extensions, TLSEXT_TYPE_status_request) ||
!CBB_add_u16_length_prefixed(&extensions, &contents) ||
!CBB_add_u8(&contents, TLSEXT_STATUSTYPE_ocsp) ||
!CBB_add_u24_length_prefixed(&contents, &ocsp_response) ||
!CBB_add_bytes(&ocsp_response,
CRYPTO_BUFFER_data(cert->ocsp_response.get()),
CRYPTO_BUFFER_len(cert->ocsp_response.get())) ||
!CBB_flush(&extensions)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return false;
}
}
if (ssl_signing_with_dc(hs)) {
const CRYPTO_BUFFER *raw = dc->raw.get();
if (!CBB_add_u16(&extensions, TLSEXT_TYPE_delegated_credential) ||
!CBB_add_u16(&extensions, CRYPTO_BUFFER_len(raw)) ||
!CBB_add_bytes(&extensions,
CRYPTO_BUFFER_data(raw),
CRYPTO_BUFFER_len(raw)) ||
!CBB_flush(&extensions)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return 0;
}
}
for (size_t i = 1; i < sk_CRYPTO_BUFFER_num(cert->chain.get()); i++) {
CRYPTO_BUFFER *cert_buf = sk_CRYPTO_BUFFER_value(cert->chain.get(), i);
CBB child;
if (!CBB_add_u24_length_prefixed(&certificate_list, &child) ||
!CBB_add_bytes(&child, CRYPTO_BUFFER_data(cert_buf),
CRYPTO_BUFFER_len(cert_buf)) ||
!CBB_add_u16(&certificate_list, 0 /* no extensions */)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return false;
}
}
if (!hs->cert_compression_negotiated) {
return ssl_add_message_cbb(ssl, cbb.get());
}
Array<uint8_t> msg;
if (!CBBFinishArray(cbb.get(), &msg)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return false;
}
const CertCompressionAlg *alg = nullptr;
for (const auto *candidate : ssl->ctx->cert_compression_algs.get()) {
if (candidate->alg_id == hs->cert_compression_alg_id) {
alg = candidate;
break;
}
}
if (alg == nullptr || alg->compress == nullptr) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return false;
}
CBB compressed;
body = &body_storage;
if (!ssl->method->init_message(ssl, cbb.get(), body,
SSL3_MT_COMPRESSED_CERTIFICATE) ||
!CBB_add_u16(body, hs->cert_compression_alg_id) ||
!CBB_add_u24(body, msg.size()) ||
!CBB_add_u24_length_prefixed(body, &compressed) ||
!alg->compress(ssl, &compressed, msg.data(), msg.size()) ||
!ssl_add_message_cbb(ssl, cbb.get())) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return false;
}
return true;
}
enum ssl_private_key_result_t tls13_add_certificate_verify(SSL_HANDSHAKE *hs) {
SSL *const ssl = hs->ssl;
uint16_t signature_algorithm;
if (!tls1_choose_signature_algorithm(hs, &signature_algorithm)) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
return ssl_private_key_failure;
}
ScopedCBB cbb;
CBB body;
if (!ssl->method->init_message(ssl, cbb.get(), &body,
SSL3_MT_CERTIFICATE_VERIFY) ||
!CBB_add_u16(&body, signature_algorithm)) {
OPENSSL_PUT_ERROR(SSL, ERR_R_INTERNAL_ERROR);
return ssl_private_key_failure;
}
// Sign the digest.
CBB child;
const size_t max_sig_len = EVP_PKEY_size(hs->local_pubkey.get());
uint8_t *sig;
size_t sig_len;
if (!CBB_add_u16_length_prefixed(&body, &child) ||
!CBB_reserve(&child, &sig, max_sig_len)) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
return ssl_private_key_failure;
}
Array<uint8_t> msg;
if (!tls13_get_cert_verify_signature_input(
hs, &msg,
ssl->server ? ssl_cert_verify_server : ssl_cert_verify_client)) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
return ssl_private_key_failure;
}
enum ssl_private_key_result_t sign_result = ssl_private_key_sign(
hs, sig, &sig_len, max_sig_len, signature_algorithm, msg);
if (sign_result != ssl_private_key_success) {
return sign_result;
}
if (!CBB_did_write(&child, sig_len) ||
!ssl_add_message_cbb(ssl, cbb.get())) {
return ssl_private_key_failure;
}
return ssl_private_key_success;
}
bool tls13_add_finished(SSL_HANDSHAKE *hs) {
SSL *const ssl = hs->ssl;
size_t verify_data_len;
uint8_t verify_data[EVP_MAX_MD_SIZE];
if (!tls13_finished_mac(hs, verify_data, &verify_data_len, ssl->server)) {
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
OPENSSL_PUT_ERROR(SSL, SSL_R_DIGEST_CHECK_FAILED);
return false;
}
ScopedCBB cbb;
CBB body;
if (!ssl->method->init_message(ssl, cbb.get(), &body, SSL3_MT_FINISHED) ||
!CBB_add_bytes(&body, verify_data, verify_data_len) ||
!ssl_add_message_cbb(ssl, cbb.get())) {
return false;
}
return true;
}
bool tls13_add_key_update(SSL *ssl, int update_requested) {
ScopedCBB cbb;
CBB body_cbb;
if (!ssl->method->init_message(ssl, cbb.get(), &body_cbb,
SSL3_MT_KEY_UPDATE) ||
!CBB_add_u8(&body_cbb, update_requested) ||
!ssl_add_message_cbb(ssl, cbb.get()) ||
!tls13_rotate_traffic_key(ssl, evp_aead_seal)) {
return false;
}
// Suppress KeyUpdate acknowledgments until this change is written to the
// wire. This prevents us from accumulating write obligations when read and
// write progress at different rates. See RFC 8446, section 4.6.3.
ssl->s3->key_update_pending = true;
return true;
}
static bool tls13_receive_key_update(SSL *ssl, const SSLMessage &msg) {
CBS body = msg.body;
uint8_t key_update_request;
if (!CBS_get_u8(&body, &key_update_request) ||
CBS_len(&body) != 0 ||
(key_update_request != SSL_KEY_UPDATE_NOT_REQUESTED &&
key_update_request != SSL_KEY_UPDATE_REQUESTED)) {
OPENSSL_PUT_ERROR(SSL, SSL_R_DECODE_ERROR);
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_DECODE_ERROR);
return false;
}
if (!tls13_rotate_traffic_key(ssl, evp_aead_open)) {
return false;
}
// Acknowledge the KeyUpdate
if (key_update_request == SSL_KEY_UPDATE_REQUESTED &&
!ssl->s3->key_update_pending &&
!tls13_add_key_update(ssl, SSL_KEY_UPDATE_NOT_REQUESTED)) {
return false;
}
return true;
}
bool tls13_post_handshake(SSL *ssl, const SSLMessage &msg) {
if (msg.type == SSL3_MT_KEY_UPDATE) {
ssl->s3->key_update_count++;
if (ssl->quic_method != nullptr ||
ssl->s3->key_update_count > kMaxKeyUpdates) {
OPENSSL_PUT_ERROR(SSL, SSL_R_TOO_MANY_KEY_UPDATES);
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
return false;
}
return tls13_receive_key_update(ssl, msg);
}
ssl->s3->key_update_count = 0;
if (msg.type == SSL3_MT_NEW_SESSION_TICKET && !ssl->server) {
return tls13_process_new_session_ticket(ssl, msg);
}
ssl_send_alert(ssl, SSL3_AL_FATAL, SSL_AD_UNEXPECTED_MESSAGE);
OPENSSL_PUT_ERROR(SSL, SSL_R_UNEXPECTED_MESSAGE);
return false;
}
BSSL_NAMESPACE_END
Reference in New Issue View Git Blame Copy Permalink