Decouple the handshake buffer and digest.
The handshake hash is initialized from the buffer as soon as the cipher
is known. When adding a message to the transcript, independently update
the buffer and rolling hash, whichever is active. This avoids the
complications around dont_free_handshake_buffer and EMS.
BUG=492371
Change-Id: I3b1065796a50fd1be5d42ead7210c2f253ef0aca
Reviewed-on: https://boringssl-review.googlesource.com/5615
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/internal.h b/ssl/internal.h
index 7f2dd52..1d6426b 100644
--- a/ssl/internal.h
+++ b/ssl/internal.h
@@ -398,6 +398,35 @@
int custom_ext_add_serverhello(SSL *ssl, CBB *extensions);
+/* Handshake hash.
+ *
+ * The TLS handshake maintains a transcript of all handshake messages. At
+ * various points in the protocol, this is either a handshake buffer, a rolling
+ * hash (selected by cipher suite) or both. */
+
+/* ssl3_init_handshake_buffer initializes the handshake buffer and resets the
+ * handshake hash. It returns one success and zero on failure. */
+int ssl3_init_handshake_buffer(SSL *ssl);
+
+/* ssl3_init_handshake_hash initializes the handshake hash based on the pending
+ * cipher and the contents of the handshake buffer. Subsequent calls to
+ * |ssl3_update_handshake_hash| will update the rolling hash. It returns one on
+ * success and zero on failure. It is an error to call this function after the
+ * handshake buffer is released. */
+int ssl3_init_handshake_hash(SSL *ssl);
+
+/* ssl3_free_handshake_buffer releases the handshake buffer. Subsequent calls
+ * to |ssl3_update_handshake_hash| will not update the handshake buffer. */
+void ssl3_free_handshake_buffer(SSL *ssl);
+
+/* ssl3_free_handshake_hash releases the handshake hash. */
+void ssl3_free_handshake_hash(SSL *s);
+
+/* ssl3_update_handshake_hash adds |in| to the handshake buffer and handshake
+ * hash, whichever is enabled. It returns one on success and zero on failure. */
+int ssl3_update_handshake_hash(SSL *ssl, const uint8_t *in, size_t in_len);
+
+
/* Underdocumented functions.
*
* Functions below here haven't been touched up and may be underdocumented. */
@@ -880,7 +909,6 @@
* |len|. It returns one on success and zero on failure. */
int ssl_fill_hello_random(uint8_t *out, size_t len, int is_server);
-int ssl3_init_finished_mac(SSL *s);
int ssl3_send_server_certificate(SSL *s);
int ssl3_send_new_session_ticket(SSL *s);
int ssl3_send_cert_status(SSL *s);
@@ -921,8 +949,6 @@
int ssl3_write_bytes(SSL *s, int type, const void *buf, int len);
int ssl3_final_finish_mac(SSL *s, const char *sender, int slen, uint8_t *p);
int ssl3_cert_verify_mac(SSL *s, int md_nid, uint8_t *p);
-int ssl3_finish_mac(SSL *s, const uint8_t *buf, int len);
-void ssl3_free_digest_list(SSL *s);
int ssl3_output_cert_chain(SSL *s);
const SSL_CIPHER *ssl3_choose_cipher(
SSL *ssl, STACK_OF(SSL_CIPHER) *clnt,
@@ -932,12 +958,6 @@
int ssl3_release_read_buffer(SSL *s);
int ssl3_release_write_buffer(SSL *s);
-enum should_free_handshake_buffer_t {
- free_handshake_buffer,
- dont_free_handshake_buffer,
-};
-int ssl3_digest_cached_records(SSL *s, enum should_free_handshake_buffer_t);
-
int ssl3_new(SSL *s);
void ssl3_free(SSL *s);
int ssl3_accept(SSL *s);
