Push alert handling down into the record functions.
Alert handling is more-or-less identical across all contexts. Push it down from
read_bytes into the low-level record functions. This also deduplicates the code
shared between TLS and DTLS.
Now the only type mismatch managed by read_bytes is if we get handshake data in
read_app_data.
Change-Id: Ia8331897b304566e66d901899cfbf31d2870194e
Reviewed-on: https://boringssl-review.googlesource.com/8124
Reviewed-by: Steven Valdez <svaldez@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
diff --git a/ssl/s3_pkt.c b/ssl/s3_pkt.c
index 4b5138e..04d41be 100644
--- a/ssl/s3_pkt.c
+++ b/ssl/s3_pkt.c
@@ -123,15 +123,10 @@
static int do_ssl3_write(SSL *ssl, int type, const uint8_t *buf, unsigned len);
-/* kMaxWarningAlerts is the number of consecutive warning alerts that will be
- * processed. */
-static const uint8_t kMaxWarningAlerts = 4;
-
/* ssl3_get_record reads a new input record. On success, it places it in
* |ssl->s3->rrec| and returns one. Otherwise it returns <= 0 on error or if
* more data is needed. */
static int ssl3_get_record(SSL *ssl) {
- int ret;
again:
switch (ssl->s3->recv_shutdown) {
case ssl_shutdown_none:
@@ -144,9 +139,9 @@
}
/* Ensure the buffer is large enough to decrypt in-place. */
- ret = ssl_read_buffer_extend_to(ssl, ssl_record_prefix_len(ssl));
- if (ret <= 0) {
- return ret;
+ int read_ret = ssl_read_buffer_extend_to(ssl, ssl_record_prefix_len(ssl));
+ if (read_ret <= 0) {
+ return read_ret;
}
assert(ssl_read_buffer_len(ssl) >= ssl_record_prefix_len(ssl));
@@ -154,11 +149,21 @@
size_t max_out = ssl_read_buffer_len(ssl) - ssl_record_prefix_len(ssl);
uint8_t type, alert;
size_t len, consumed;
- switch (tls_open_record(ssl, &type, out, &len, &consumed, &alert, max_out,
- ssl_read_buffer(ssl), ssl_read_buffer_len(ssl))) {
- case ssl_open_record_success:
- ssl_read_buffer_consume(ssl, consumed);
+ enum ssl_open_record_t open_ret =
+ tls_open_record(ssl, &type, out, &len, &consumed, &alert, max_out,
+ ssl_read_buffer(ssl), ssl_read_buffer_len(ssl));
+ if (open_ret != ssl_open_record_partial) {
+ ssl_read_buffer_consume(ssl, consumed);
+ }
+ switch (open_ret) {
+ case ssl_open_record_partial:
+ read_ret = ssl_read_buffer_extend_to(ssl, consumed);
+ if (read_ret <= 0) {
+ return read_ret;
+ }
+ goto again;
+ case ssl_open_record_success:
if (len > 0xffff) {
OPENSSL_PUT_ERROR(SSL, ERR_R_OVERFLOW);
return -1;
@@ -170,16 +175,14 @@
rr->data = out;
return 1;
- case ssl_open_record_partial:
- ret = ssl_read_buffer_extend_to(ssl, consumed);
- if (ret <= 0) {
- return ret;
- }
+ case ssl_open_record_discard:
goto again;
- case ssl_open_record_discard:
- ssl_read_buffer_consume(ssl, consumed);
- goto again;
+ case ssl_open_record_close_notify:
+ return 0;
+
+ case ssl_open_record_fatal_alert:
+ return -1;
case ssl_open_record_error:
ssl3_send_alert(ssl, SSL3_AL_FATAL, alert);
@@ -402,8 +405,6 @@
/* we now have a packet which can be read and processed */
if (type != 0 && type == rr->type) {
- ssl->s3->warning_alert_count = 0;
-
/* Discard empty records. */
if (rr->length == 0) {
goto start;
@@ -495,56 +496,6 @@
goto start;
}
- /* If an alert record, process the alert. */
- if (rr->type == SSL3_RT_ALERT) {
- /* Alerts records may not contain fragmented or multiple alerts. */
- if (rr->length != 2) {
- al = SSL_AD_DECODE_ERROR;
- OPENSSL_PUT_ERROR(SSL, SSL_R_BAD_ALERT);
- goto f_err;
- }
-
- ssl_do_msg_callback(ssl, 0 /* read */, ssl->version, SSL3_RT_ALERT,
- rr->data, 2);
-
- const uint8_t alert_level = rr->data[0];
- const uint8_t alert_descr = rr->data[1];
- rr->length -= 2;
- rr->data += 2;
-
- uint16_t alert = (alert_level << 8) | alert_descr;
- ssl_do_info_callback(ssl, SSL_CB_READ_ALERT, alert);
-
- if (alert_level == SSL3_AL_WARNING) {
- if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
- ssl->s3->recv_shutdown = ssl_shutdown_close_notify;
- return 0;
- }
-
- ssl->s3->warning_alert_count++;
- if (ssl->s3->warning_alert_count > kMaxWarningAlerts) {
- al = SSL_AD_UNEXPECTED_MESSAGE;
- OPENSSL_PUT_ERROR(SSL, SSL_R_TOO_MANY_WARNING_ALERTS);
- goto f_err;
- }
- } else if (alert_level == SSL3_AL_FATAL) {
- char tmp[16];
-
- OPENSSL_PUT_ERROR(SSL, SSL_AD_REASON_OFFSET + alert_descr);
- BIO_snprintf(tmp, sizeof(tmp), "%d", alert_descr);
- ERR_add_error_data(2, "SSL alert number ", tmp);
- ssl->s3->recv_shutdown = ssl_shutdown_fatal_alert;
- SSL_CTX_remove_session(ssl->ctx, ssl->session);
- return 0;
- } else {
- al = SSL_AD_ILLEGAL_PARAMETER;
- OPENSSL_PUT_ERROR(SSL, SSL_R_UNKNOWN_ALERT_TYPE);
- goto f_err;
- }
-
- goto start;
- }
-
if (type == 0) {
/* This may only occur from read_close_notify. */
assert(ssl->s3->send_shutdown == ssl_shutdown_close_notify);
