From bcf2907c685cf1bde9eb92928fad5e85c483563b Mon Sep 17 00:00:00 2001 From: Matt Caswell Date: Fri, 8 Jun 2018 17:18:03 +0100 Subject: [PATCH] Remodel the if sequence for handling alerts Reviewed-by: Andy Polyakov (Merged from https://github.com/openssl/openssl/pull/6370) --- ssl/record/rec_layer_s3.c | 64 +++++++++++++++++---------------------- 1 file changed, 28 insertions(+), 36 deletions(-) diff --git a/ssl/record/rec_layer_s3.c b/ssl/record/rec_layer_s3.c index a3dee2de81..75b506bd85 100644 --- a/ssl/record/rec_layer_s3.c +++ b/ssl/record/rec_layer_s3.c @@ -1209,6 +1209,7 @@ int ssl3_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf, SSL3_RECORD *rr; SSL3_BUFFER *rbuf; void (*cb) (const SSL *ssl, int type2, int val) = NULL; + int is_tls13 = SSL_IS_TLS13(s); rbuf = &s->rlayer.rbuf; @@ -1340,7 +1341,7 @@ int ssl3_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf, if (type == SSL3_RECORD_get_type(rr) || (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC && type == SSL3_RT_HANDSHAKE && recvd_type != NULL - && !SSL_IS_TLS13(s))) { + && !is_tls13)) { /* * SSL3_RT_APPLICATION_DATA or * SSL3_RT_HANDSHAKE or @@ -1497,7 +1498,6 @@ int ssl3_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf, if (SSL3_RECORD_get_type(rr) == SSL3_RT_ALERT) { unsigned int alert_level, alert_descr; - int tls13_user_cancelled; unsigned char *alert_bytes = SSL3_RECORD_get_data(rr) + SSL3_RECORD_get_off(rr); PACKET alert; @@ -1525,9 +1525,8 @@ int ssl3_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf, cb(s, SSL_CB_READ_ALERT, j); } - tls13_user_cancelled = SSL_IS_TLS13(s) - && alert_descr == SSL_AD_USER_CANCELLED; - if (alert_level == SSL3_AL_WARNING || tls13_user_cancelled) { + if (alert_level == SSL3_AL_WARNING + || (is_tls13 && alert_descr == SSL_AD_USER_CANCELLED)) { s->s3->warn_alert = alert_descr; SSL3_RECORD_set_read(rr); @@ -1537,38 +1536,19 @@ int ssl3_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf, SSL_R_TOO_MANY_WARN_ALERTS); return -1; } - - /* - * Apart from close_notify the only other warning alert in TLSv1.3 - * is user_cancelled - which we just ignore. - */ - if (tls13_user_cancelled) - goto start; - } - - if (alert_descr == SSL_AD_CLOSE_NOTIFY - && (SSL_IS_TLS13(s) || alert_level == SSL3_AL_WARNING)) { - s->shutdown |= SSL_RECEIVED_SHUTDOWN; - return 0; } /* - * This is a warning but we receive it if we requested - * renegotiation and the peer denied it. Terminate with a fatal - * alert because if application tried to renegotiate it - * presumably had a good reason and expects it to succeed. In - * future we might have a renegotiation where we don't care if - * the peer refused it where we carry on. + * Apart from close_notify the only other warning alert in TLSv1.3 + * is user_cancelled - which we just ignore. */ - if (alert_descr == SSL_AD_NO_RENEGOTIATION - && !SSL_IS_TLS13(s) - && alert_level == SSL3_AL_WARNING) { - SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_SSL3_READ_BYTES, - SSL_R_NO_RENEGOTIATION); - return -1; - } - - if (alert_level == SSL3_AL_FATAL || SSL_IS_TLS13(s)) { + if (is_tls13 && alert_descr == SSL_AD_USER_CANCELLED) { + goto start; + } else if (alert_descr == SSL_AD_CLOSE_NOTIFY + && (is_tls13 || alert_level == SSL3_AL_WARNING)) { + s->shutdown |= SSL_RECEIVED_SHUTDOWN; + return 0; + } else if (alert_level == SSL3_AL_FATAL || is_tls13) { char tmp[16]; s->rwstate = SSL_NOTHING; @@ -1581,11 +1561,23 @@ int ssl3_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf, SSL3_RECORD_set_read(rr); SSL_CTX_remove_session(s->session_ctx, s->session); return 0; - } else { - SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_SSL3_READ_BYTES, - SSL_R_UNKNOWN_ALERT_TYPE); + } else if (alert_descr == SSL_AD_NO_RENEGOTIATION) { + /* + * This is a warning but we receive it if we requested + * renegotiation and the peer denied it. Terminate with a fatal + * alert because if application tried to renegotiate it + * presumably had a good reason and expects it to succeed. In + * future we might have a renegotiation where we don't care if + * the peer refused it where we carry on. + */ + SSLfatal(s, SSL_AD_HANDSHAKE_FAILURE, SSL_F_SSL3_READ_BYTES, + SSL_R_NO_RENEGOTIATION); return -1; } + + SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_SSL3_READ_BYTES, + SSL_R_UNKNOWN_ALERT_TYPE); + return -1; } if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a -- 2.25.1