Take the version parameter out of ssl_do_msg_callback.

This will make it a little easier to store the normalized version rather
than the wire version. Also document the V2ClientHello behavior.

Change-Id: I5ce9ccce44ca48be2e60ddf293c0fab6bba1356e
Reviewed-on: https://boringssl-review.googlesource.com/11121
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

9 files changed, 48 insertions, 30 deletions

diff --git a/include/openssl/ssl.h b/include/openssl/ssl.h
index 256e3a03..c68dc12c 100644
--- a/include/openssl/ssl.h
+++ b/include/openssl/ssl.h
@@ -2801,7 +2801,10 @@ OPENSSL_EXPORT void SSL_get_structure_sizes(size_t *ssl_size,
  * For each handshake message, ChangeCipherSpec, and alert, |version| is the
  * protocol version and |content_type| is the corresponding record type. The
  * |len| bytes from |buf| contain the handshake message, one-byte
- * ChangeCipherSpec body, and two-byte alert, respectively. */
+ * ChangeCipherSpec body, and two-byte alert, respectively.
+ *
+ * For a V2ClientHello, |version| is |SSL2_VERSION|, |content_type| is zero, and
+ * the |len| bytes from |buf| contain the V2ClientHello structure. */
 OPENSSL_EXPORT void SSL_CTX_set_msg_callback(
     SSL_CTX *ctx, void (*cb)(int write_p, int version, int content_type,
                              const void *buf, size_t len, SSL *ssl, void *arg));
diff --git a/ssl/d1_both.c b/ssl/d1_both.c
index 5ea29da4..7bb2de28 100644
--- a/ssl/d1_both.c
+++ b/ssl/d1_both.c
@@ -437,8 +437,8 @@ int dtls1_get_message(SSL *ssl, int msg_type,
     return -1;
   }
 
-  ssl_do_msg_callback(ssl, 0 /* read */, ssl->version, SSL3_RT_HANDSHAKE,
-                      frag->data, ssl->init_num + DTLS1_HM_HEADER_LENGTH);
+  ssl_do_msg_callback(ssl, 0 /* read */, SSL3_RT_HANDSHAKE, frag->data,
+                      ssl->init_num + DTLS1_HM_HEADER_LENGTH);
   return 1;
 }
 
@@ -567,9 +567,8 @@ static int dtls1_write_change_cipher_spec(SSL *ssl,
     return ret;
   }
 
-  ssl_do_msg_callback(ssl, 1 /* write */, ssl->version,
-                      SSL3_RT_CHANGE_CIPHER_SPEC, kChangeCipherSpec,
-                      sizeof(kChangeCipherSpec));
+  ssl_do_msg_callback(ssl, 1 /* write */, SSL3_RT_CHANGE_CIPHER_SPEC,
+                      kChangeCipherSpec, sizeof(kChangeCipherSpec));
   return 1;
 }
 
@@ -667,8 +666,7 @@ static int dtls1_do_handshake_write(SSL *ssl, size_t *out_offset,
     offset += todo;
   } while (CBS_len(&body) != 0);
 
-  ssl_do_msg_callback(ssl, 1 /* write */, ssl->version, SSL3_RT_HANDSHAKE, in,
-                      len);
+  ssl_do_msg_callback(ssl, 1 /* write */, SSL3_RT_HANDSHAKE, in, len);
 
   ret = 1;
 
diff --git a/ssl/d1_pkt.c b/ssl/d1_pkt.c
index 574fd4cd..099de5db 100644
--- a/ssl/d1_pkt.c
+++ b/ssl/d1_pkt.c
@@ -312,8 +312,8 @@ again:
     return -1;
   }
 
-  ssl_do_msg_callback(ssl, 0 /* read */, ssl->version,
-                      SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, rr->length);
+  ssl_do_msg_callback(ssl, 0 /* read */, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data,
+                      rr->length);
 
   rr->length = 0;
   ssl_read_buffer_discard(ssl);
@@ -409,8 +409,8 @@ int dtls1_dispatch_alert(SSL *ssl) {
     BIO_flush(ssl->wbio);
   }
 
-  ssl_do_msg_callback(ssl, 1 /* write */, ssl->version, SSL3_RT_ALERT,
-                      ssl->s3->send_alert, 2);
+  ssl_do_msg_callback(ssl, 1 /* write */, SSL3_RT_ALERT, ssl->s3->send_alert,
+                      2);
 
   int alert = (ssl->s3->send_alert[0] << 8) | ssl->s3->send_alert[1];
   ssl_do_info_callback(ssl, SSL_CB_WRITE_ALERT, alert);
diff --git a/ssl/dtls_record.c b/ssl/dtls_record.c
index e784e556..ffe4053e 100644
--- a/ssl/dtls_record.c
+++ b/ssl/dtls_record.c
@@ -198,7 +198,7 @@ enum ssl_open_record_t dtls_open_record(SSL *ssl, uint8_t *out_type, CBS *out,
     return ssl_open_record_discard;
   }
 
-  ssl_do_msg_callback(ssl, 0 /* read */, 0, SSL3_RT_HEADER, in,
+  ssl_do_msg_callback(ssl, 0 /* read */, SSL3_RT_HEADER, in,
                       DTLS1_RT_HEADER_LENGTH);
 
   uint16_t epoch = (((uint16_t)sequence[0]) << 8) | sequence[1];
@@ -302,7 +302,7 @@ int dtls_seal_record(SSL *ssl, uint8_t *out, size_t *out_len, size_t max_out,
 
   *out_len = DTLS1_RT_HEADER_LENGTH + ciphertext_len;
 
-  ssl_do_msg_callback(ssl, 1 /* write */, 0, SSL3_RT_HEADER, out,
+  ssl_do_msg_callback(ssl, 1 /* write */, SSL3_RT_HEADER, out,
                       DTLS1_RT_HEADER_LENGTH);
 
   return 1;
diff --git a/ssl/internal.h b/ssl/internal.h
index 0bc0b8ed..bdb392c9 100644
--- a/ssl/internal.h
+++ b/ssl/internal.h
@@ -683,7 +683,7 @@ void dtls_clear_outgoing_messages(SSL *ssl);
 void ssl_do_info_callback(const SSL *ssl, int type, int value);
 
 /* ssl_do_msg_callback calls |ssl|'s message callback, if set. */
-void ssl_do_msg_callback(SSL *ssl, int is_write, int version, int content_type,
+void ssl_do_msg_callback(SSL *ssl, int is_write, int content_type,
                          const void *buf, size_t len);
 
 
diff --git a/ssl/s3_both.c b/ssl/s3_both.c
index 23cda928..e77e8ca6 100644
--- a/ssl/s3_both.c
+++ b/ssl/s3_both.c
@@ -181,7 +181,7 @@ static int ssl3_do_write(SSL *ssl, int type, const uint8_t *data, size_t len) {
 
   /* ssl3_write_bytes writes the data in its entirety. */
   assert((size_t)ret == len);
-  ssl_do_msg_callback(ssl, 1 /* write */, ssl->version, type, data, len);
+  ssl_do_msg_callback(ssl, 1 /* write */, type, data, len);
   return 1;
 }
 
@@ -477,7 +477,7 @@ static int read_v2_client_hello(SSL *ssl, int *out_is_v2_client_hello) {
     return -1;
   }
 
-  ssl_do_msg_callback(ssl, 0 /* read */, SSL2_VERSION, 0,
+  ssl_do_msg_callback(ssl, 0 /* read */, 0 /* V2ClientHello */,
                       CBS_data(&v2_client_hello), CBS_len(&v2_client_hello));
 
   uint8_t msg_type;
@@ -631,8 +631,8 @@ again:
   }
 
   /* We have now received a complete message. */
-  ssl_do_msg_callback(ssl, 0 /* read */, ssl->version, SSL3_RT_HANDSHAKE,
-                      ssl->init_buf->data, ssl->init_buf->length);
+  ssl_do_msg_callback(ssl, 0 /* read */, SSL3_RT_HANDSHAKE, ssl->init_buf->data,
+                      ssl->init_buf->length);
 
   ssl->s3->tmp.message_type = ((const uint8_t *)ssl->init_buf->data)[0];
   ssl->init_msg = (uint8_t*)ssl->init_buf->data + SSL3_HM_HEADER_LENGTH;
diff --git a/ssl/s3_pkt.c b/ssl/s3_pkt.c
index b1a6aa99..fda9a251 100644
--- a/ssl/s3_pkt.c
+++ b/ssl/s3_pkt.c
@@ -407,8 +407,8 @@ int ssl3_read_change_cipher_spec(SSL *ssl) {
     return -1;
   }
 
-  ssl_do_msg_callback(ssl, 0 /* read */, ssl->version,
-                      SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, rr->length);
+  ssl_do_msg_callback(ssl, 0 /* read */, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data,
+                      rr->length);
 
   rr->length = 0;
   ssl_read_buffer_discard(ssl);
@@ -487,8 +487,8 @@ int ssl3_dispatch_alert(SSL *ssl) {
     BIO_flush(ssl->wbio);
   }
 
-  ssl_do_msg_callback(ssl, 1 /* write */, ssl->version, SSL3_RT_ALERT,
-                      ssl->s3->send_alert, 2);
+  ssl_do_msg_callback(ssl, 1 /* write */, SSL3_RT_ALERT, ssl->s3->send_alert,
+                      2);
 
   int alert = (ssl->s3->send_alert[0] << 8) | ssl->s3->send_alert[1];
   ssl_do_info_callback(ssl, SSL_CB_WRITE_ALERT, alert);
diff --git a/ssl/ssl_lib.c b/ssl/ssl_lib.c
index aa039992..3e27f37d 100644
--- a/ssl/ssl_lib.c
+++ b/ssl/ssl_lib.c
@@ -2913,12 +2913,29 @@ void ssl_do_info_callback(const SSL *ssl, int type, int value) {
   }
 }
 
-void ssl_do_msg_callback(SSL *ssl, int is_write, int version, int content_type,
+void ssl_do_msg_callback(SSL *ssl, int is_write, int content_type,
                          const void *buf, size_t len) {
-  if (ssl->msg_callback != NULL) {
-    ssl->msg_callback(is_write, version, content_type, buf, len, ssl,
-                      ssl->msg_callback_arg);
+  if (ssl->msg_callback == NULL) {
+    return;
   }
+
+  /* |version| is zero when calling for |SSL3_RT_HEADER| and |SSL2_VERSION| for
+   * a V2ClientHello. */
+  int version;
+  switch (content_type) {
+    case 0:
+      /* V2ClientHello */
+      version = SSL2_VERSION;
+      break;
+    case SSL3_RT_HEADER:
+      version = 0;
+      break;
+    default:
+      version = ssl->version;
+  }
+
+  ssl->msg_callback(is_write, version, content_type, buf, len, ssl,
+                    ssl->msg_callback_arg);
 }
 
 int SSL_CTX_sess_connect(const SSL_CTX *ctx) { return 0; }
diff --git a/ssl/tls_record.c b/ssl/tls_record.c
index 8915b391..7041ce34 100644
--- a/ssl/tls_record.c
+++ b/ssl/tls_record.c
@@ -232,7 +232,7 @@ enum ssl_open_record_t tls_open_record(SSL *ssl, uint8_t *out_type, CBS *out,
     return ssl_open_record_partial;
   }
 
-  ssl_do_msg_callback(ssl, 0 /* read */, 0, SSL3_RT_HEADER, in,
+  ssl_do_msg_callback(ssl, 0 /* read */, SSL3_RT_HEADER, in,
                       SSL3_RT_HEADER_LENGTH);
 
   /* Decrypt the body in-place. */
@@ -349,7 +349,7 @@ static int do_seal_record(SSL *ssl, uint8_t *out, size_t *out_len,
 
   *out_len = SSL3_RT_HEADER_LENGTH + ciphertext_len;
 
-  ssl_do_msg_callback(ssl, 1 /* write */, 0, SSL3_RT_HEADER, out,
+  ssl_do_msg_callback(ssl, 1 /* write */, SSL3_RT_HEADER, out,
                       SSL3_RT_HEADER_LENGTH);
   return 1;
 }
@@ -414,7 +414,7 @@ enum ssl_open_record_t ssl_process_alert(SSL *ssl, uint8_t *out_alert,
     return ssl_open_record_error;
   }
 
-  ssl_do_msg_callback(ssl, 0 /* read */, ssl->version, SSL3_RT_ALERT, in, in_len);
+  ssl_do_msg_callback(ssl, 0 /* read */, SSL3_RT_ALERT, in, in_len);
 
   const uint8_t alert_level = in[0];
   const uint8_t alert_descr = in[1];