C++ the ticket keys a bit.
While I'm here, remove the silly "tlsext_" prefix. At this point it's no
longer novel that a feature is encoded in an extension.
Change-Id: Ib5fbd2121333a213bdda0332885a8c90036ebc4d
Reviewed-on: https://boringssl-review.googlesource.com/29592
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/internal.h b/ssl/internal.h
index d71ea57..cdb5cff 100644
--- a/ssl/internal.h
+++ b/ssl/internal.h
@@ -2032,17 +2032,17 @@
// crypto/x509.
extern const SSL_X509_METHOD ssl_noop_x509_method;
-struct tlsext_ticket_key {
+struct TicketKey {
static constexpr bool kAllowUniquePtr = true;
- uint8_t name[SSL_TICKET_KEY_NAME_LEN];
- uint8_t hmac_key[16];
- uint8_t aes_key[16];
+ uint8_t name[SSL_TICKET_KEY_NAME_LEN] = {0};
+ uint8_t hmac_key[16] = {0};
+ uint8_t aes_key[16] = {0};
// next_rotation_tv_sec is the time (in seconds from the epoch) when the
// current key should be superseded by a new key, or the time when a previous
// key should be dropped. If zero, then the key should not be automatically
// rotated.
- uint64_t next_rotation_tv_sec;
+ uint64_t next_rotation_tv_sec = 0;
};
} // namespace bssl
@@ -2952,17 +2952,16 @@
int (*tlsext_servername_callback)(SSL *, int *, void *) = nullptr;
void *tlsext_servername_arg = nullptr;
- // RFC 4507 session ticket keys. |tlsext_ticket_key_current| may be NULL
- // before the first handshake and |tlsext_ticket_key_prev| may be NULL at any
- // time. Automatically generated ticket keys are rotated as needed at
- // handshake time. Hence, all access must be synchronized through |lock|.
- bssl::tlsext_ticket_key *tlsext_ticket_key_current = nullptr;
- bssl::tlsext_ticket_key *tlsext_ticket_key_prev = nullptr;
+ // RFC 4507 session ticket keys. |ticket_key_current| may be NULL before the
+ // first handshake and |ticket_key_prev| may be NULL at any time.
+ // Automatically generated ticket keys are rotated as needed at handshake
+ // time. Hence, all access must be synchronized through |lock|.
+ bssl::UniquePtr<bssl::TicketKey> ticket_key_current;
+ bssl::UniquePtr<bssl::TicketKey> ticket_key_prev;
// Callback to support customisation of ticket key setting
- int (*tlsext_ticket_key_cb)(SSL *ssl, uint8_t *name, uint8_t *iv,
- EVP_CIPHER_CTX *ectx, HMAC_CTX *hctx,
- int enc) = nullptr;
+ int (*ticket_key_cb)(SSL *ssl, uint8_t *name, uint8_t *iv,
+ EVP_CIPHER_CTX *ectx, HMAC_CTX *hctx, int enc) = nullptr;
// Server-only: psk_identity_hint is the default identity hint to send in
// PSK-based key exchanges.
diff --git a/ssl/ssl_lib.cc b/ssl/ssl_lib.cc
index 39c5d92..4e53e7c 100644
--- a/ssl/ssl_lib.cc
+++ b/ssl/ssl_lib.cc
@@ -569,8 +569,6 @@
x509_method->ssl_ctx_free(this);
sk_CertCompressionAlg_pop_free(cert_compression_algs,
Delete<CertCompressionAlg>);
- OPENSSL_free(tlsext_ticket_key_current);
- OPENSSL_free(tlsext_ticket_key_prev);
}
SSL_CTX *SSL_CTX_new(const SSL_METHOD *method) {
@@ -1675,9 +1673,9 @@
uint8_t *out_bytes = reinterpret_cast<uint8_t *>(out);
MutexReadLock lock(&ctx->lock);
- OPENSSL_memcpy(out_bytes, ctx->tlsext_ticket_key_current->name, 16);
- OPENSSL_memcpy(out_bytes + 16, ctx->tlsext_ticket_key_current->hmac_key, 16);
- OPENSSL_memcpy(out_bytes + 32, ctx->tlsext_ticket_key_current->aes_key, 16);
+ OPENSSL_memcpy(out_bytes, ctx->ticket_key_current->name, 16);
+ OPENSSL_memcpy(out_bytes + 16, ctx->ticket_key_current->hmac_key, 16);
+ OPENSSL_memcpy(out_bytes + 32, ctx->ticket_key_current->aes_key, 16);
return 1;
}
@@ -1689,22 +1687,19 @@
OPENSSL_PUT_ERROR(SSL, SSL_R_INVALID_TICKET_KEYS_LENGTH);
return 0;
}
- if (!ctx->tlsext_ticket_key_current) {
- ctx->tlsext_ticket_key_current =
- (tlsext_ticket_key *)OPENSSL_malloc(sizeof(tlsext_ticket_key));
- if (!ctx->tlsext_ticket_key_current) {
- return 0;
- }
+ auto key = MakeUnique<TicketKey>();
+ if (!key) {
+ return 0;
}
- OPENSSL_memset(ctx->tlsext_ticket_key_current, 0, sizeof(tlsext_ticket_key));
const uint8_t *in_bytes = reinterpret_cast<const uint8_t *>(in);
- OPENSSL_memcpy(ctx->tlsext_ticket_key_current->name, in_bytes, 16);
- OPENSSL_memcpy(ctx->tlsext_ticket_key_current->hmac_key, in_bytes + 16, 16);
- OPENSSL_memcpy(ctx->tlsext_ticket_key_current->aes_key, in_bytes + 32, 16);
- OPENSSL_free(ctx->tlsext_ticket_key_prev);
- ctx->tlsext_ticket_key_prev = nullptr;
- // Disable automatic key rotation.
- ctx->tlsext_ticket_key_current->next_rotation_tv_sec = 0;
+ OPENSSL_memcpy(key->name, in_bytes, 16);
+ OPENSSL_memcpy(key->hmac_key, in_bytes + 16, 16);
+ OPENSSL_memcpy(key->aes_key, in_bytes + 32, 16);
+ // Disable automatic key rotation for manually-configured keys. This is now
+ // the caller's responsibility.
+ key->next_rotation_tv_sec = 0;
+ ctx->ticket_key_current = std::move(key);
+ ctx->ticket_key_prev.reset();
return 1;
}
@@ -1712,7 +1707,7 @@
SSL_CTX *ctx, int (*callback)(SSL *ssl, uint8_t *key_name, uint8_t *iv,
EVP_CIPHER_CTX *ctx, HMAC_CTX *hmac_ctx,
int encrypt)) {
- ctx->tlsext_ticket_key_cb = callback;
+ ctx->ticket_key_cb = callback;
return 1;
}
diff --git a/ssl/ssl_session.cc b/ssl/ssl_session.cc
index d5af8aa..70be17e 100644
--- a/ssl/ssl_session.cc
+++ b/ssl/ssl_session.cc
@@ -414,47 +414,44 @@
// Avoid acquiring a write lock in the common case (i.e. a non-default key
// is used or the default keys have not expired yet).
MutexReadLock lock(&ctx->lock);
- if (ctx->tlsext_ticket_key_current &&
- (ctx->tlsext_ticket_key_current->next_rotation_tv_sec == 0 ||
- ctx->tlsext_ticket_key_current->next_rotation_tv_sec > now.tv_sec) &&
- (!ctx->tlsext_ticket_key_prev ||
- ctx->tlsext_ticket_key_prev->next_rotation_tv_sec > now.tv_sec)) {
+ if (ctx->ticket_key_current &&
+ (ctx->ticket_key_current->next_rotation_tv_sec == 0 ||
+ ctx->ticket_key_current->next_rotation_tv_sec > now.tv_sec) &&
+ (!ctx->ticket_key_prev ||
+ ctx->ticket_key_prev->next_rotation_tv_sec > now.tv_sec)) {
return 1;
}
}
MutexWriteLock lock(&ctx->lock);
- if (!ctx->tlsext_ticket_key_current ||
- (ctx->tlsext_ticket_key_current->next_rotation_tv_sec != 0 &&
- ctx->tlsext_ticket_key_current->next_rotation_tv_sec <= now.tv_sec)) {
+ if (!ctx->ticket_key_current ||
+ (ctx->ticket_key_current->next_rotation_tv_sec != 0 &&
+ ctx->ticket_key_current->next_rotation_tv_sec <= now.tv_sec)) {
// The current key has not been initialized or it is expired.
- auto new_key = bssl::MakeUnique<struct tlsext_ticket_key>();
+ auto new_key = bssl::MakeUnique<TicketKey>();
if (!new_key) {
return 0;
}
- OPENSSL_memset(new_key.get(), 0, sizeof(struct tlsext_ticket_key));
- if (ctx->tlsext_ticket_key_current) {
+ RAND_bytes(new_key->name, 16);
+ RAND_bytes(new_key->hmac_key, 16);
+ RAND_bytes(new_key->aes_key, 16);
+ new_key->next_rotation_tv_sec =
+ now.tv_sec + SSL_DEFAULT_TICKET_KEY_ROTATION_INTERVAL;
+ if (ctx->ticket_key_current) {
// The current key expired. Rotate it to prev and bump up its rotation
// timestamp. Note that even with the new rotation time it may still be
- // expired and get droppped below.
- ctx->tlsext_ticket_key_current->next_rotation_tv_sec +=
+ // expired and get dropped below.
+ ctx->ticket_key_current->next_rotation_tv_sec +=
SSL_DEFAULT_TICKET_KEY_ROTATION_INTERVAL;
- OPENSSL_free(ctx->tlsext_ticket_key_prev);
- ctx->tlsext_ticket_key_prev = ctx->tlsext_ticket_key_current;
+ ctx->ticket_key_prev = std::move(ctx->ticket_key_current);
}
- ctx->tlsext_ticket_key_current = new_key.release();
- RAND_bytes(ctx->tlsext_ticket_key_current->name, 16);
- RAND_bytes(ctx->tlsext_ticket_key_current->hmac_key, 16);
- RAND_bytes(ctx->tlsext_ticket_key_current->aes_key, 16);
- ctx->tlsext_ticket_key_current->next_rotation_tv_sec =
- now.tv_sec + SSL_DEFAULT_TICKET_KEY_ROTATION_INTERVAL;
+ ctx->ticket_key_current = std::move(new_key);
}
// Drop an expired prev key.
- if (ctx->tlsext_ticket_key_prev &&
- ctx->tlsext_ticket_key_prev->next_rotation_tv_sec <= now.tv_sec) {
- OPENSSL_free(ctx->tlsext_ticket_key_prev);
- ctx->tlsext_ticket_key_prev = nullptr;
+ if (ctx->ticket_key_prev &&
+ ctx->ticket_key_prev->next_rotation_tv_sec <= now.tv_sec) {
+ ctx->ticket_key_prev.reset();
}
return 1;
@@ -481,9 +478,9 @@
SSL_CTX *tctx = hs->ssl->session_ctx.get();
uint8_t iv[EVP_MAX_IV_LENGTH];
uint8_t key_name[16];
- if (tctx->tlsext_ticket_key_cb != NULL) {
- if (tctx->tlsext_ticket_key_cb(hs->ssl, key_name, iv, ctx.get(), hctx.get(),
- 1 /* encrypt */) < 0) {
+ if (tctx->ticket_key_cb != NULL) {
+ if (tctx->ticket_key_cb(hs->ssl, key_name, iv, ctx.get(), hctx.get(),
+ 1 /* encrypt */) < 0) {
return 0;
}
} else {
@@ -494,12 +491,12 @@
MutexReadLock lock(&tctx->lock);
if (!RAND_bytes(iv, 16) ||
!EVP_EncryptInit_ex(ctx.get(), EVP_aes_128_cbc(), NULL,
- tctx->tlsext_ticket_key_current->aes_key, iv) ||
- !HMAC_Init_ex(hctx.get(), tctx->tlsext_ticket_key_current->hmac_key, 16,
+ tctx->ticket_key_current->aes_key, iv) ||
+ !HMAC_Init_ex(hctx.get(), tctx->ticket_key_current->hmac_key, 16,
tlsext_tick_md(), NULL)) {
return 0;
}
- OPENSSL_memcpy(key_name, tctx->tlsext_ticket_key_current->name, 16);
+ OPENSSL_memcpy(key_name, tctx->ticket_key_current->name, 16);
}
uint8_t *ptr;
diff --git a/ssl/t1_lib.cc b/ssl/t1_lib.cc
index e0e7504..fab6afe 100644
--- a/ssl/t1_lib.cc
+++ b/ssl/t1_lib.cc
@@ -3490,7 +3490,7 @@
ScopedEVP_CIPHER_CTX cipher_ctx;
ScopedHMAC_CTX hmac_ctx;
const uint8_t *iv = ticket + SSL_TICKET_KEY_NAME_LEN;
- int cb_ret = hs->ssl->session_ctx->tlsext_ticket_key_cb(
+ int cb_ret = hs->ssl->session_ctx->ticket_key_cb(
hs->ssl, (uint8_t *)ticket /* name */, (uint8_t *)iv, cipher_ctx.get(),
hmac_ctx.get(), 0 /* decrypt */);
if (cb_ret < 0) {
@@ -3522,15 +3522,15 @@
ScopedHMAC_CTX hmac_ctx;
{
MutexReadLock lock(&ctx->lock);
- const tlsext_ticket_key *key;
- if (ctx->tlsext_ticket_key_current &&
- !OPENSSL_memcmp(ctx->tlsext_ticket_key_current->name, ticket,
+ const TicketKey *key;
+ if (ctx->ticket_key_current &&
+ !OPENSSL_memcmp(ctx->ticket_key_current->name, ticket,
SSL_TICKET_KEY_NAME_LEN)) {
- key = ctx->tlsext_ticket_key_current;
- } else if (ctx->tlsext_ticket_key_prev &&
- !OPENSSL_memcmp(ctx->tlsext_ticket_key_prev->name, ticket,
+ key = ctx->ticket_key_current.get();
+ } else if (ctx->ticket_key_prev &&
+ !OPENSSL_memcmp(ctx->ticket_key_prev->name, ticket,
SSL_TICKET_KEY_NAME_LEN)) {
- key = ctx->tlsext_ticket_key_prev;
+ key = ctx->ticket_key_prev.get();
} else {
return ssl_ticket_aead_ignore_ticket;
}
@@ -3589,14 +3589,14 @@
result = ssl_decrypt_ticket_with_method(
hs, &plaintext, &plaintext_len, out_renew_ticket, ticket, ticket_len);
} else {
- // Ensure there is room for the key name and the largest IV
- // |tlsext_ticket_key_cb| may try to consume. The real limit may be lower,
- // but the maximum IV length should be well under the minimum size for the
- // session material and HMAC.
+ // Ensure there is room for the key name and the largest IV |ticket_key_cb|
+ // may try to consume. The real limit may be lower, but the maximum IV
+ // length should be well under the minimum size for the session material and
+ // HMAC.
if (ticket_len < SSL_TICKET_KEY_NAME_LEN + EVP_MAX_IV_LENGTH) {
return ssl_ticket_aead_ignore_ticket;
}
- if (hs->ssl->session_ctx->tlsext_ticket_key_cb != NULL) {
+ if (hs->ssl->session_ctx->ticket_key_cb != NULL) {
result = ssl_decrypt_ticket_with_cb(hs, &plaintext, &plaintext_len,
out_renew_ticket, ticket, ticket_len);
} else {
