diff options
Diffstat (limited to 'main/openssl/ssl/s3_pkt.c')
-rw-r--r-- | main/openssl/ssl/s3_pkt.c | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/main/openssl/ssl/s3_pkt.c b/main/openssl/ssl/s3_pkt.c index df436cf7..4a2f5d6c 100644 --- a/main/openssl/ssl/s3_pkt.c +++ b/main/openssl/ssl/s3_pkt.c @@ -273,6 +273,12 @@ int ssl3_read_n(SSL *s, int n, int max, int extend) return(n); } +/* MAX_EMPTY_RECORDS defines the number of consecutive, empty records that will + * be processed per call to ssl3_get_record. Without this limit an attacker + * could send empty records at a faster rate than we can process and cause + * ssl3_get_record to loop forever. */ +#define MAX_EMPTY_RECORDS 32 + /* Call this to get a new input record. * It will return <= 0 if more data is needed, normally due to an error * or non-blocking IO. @@ -293,6 +299,7 @@ static int ssl3_get_record(SSL *s) short version; unsigned mac_size, orig_len; size_t extra; + unsigned empty_record_count = 0; rr= &(s->s3->rrec); sess=s->session; @@ -523,7 +530,17 @@ printf("\n"); s->packet_length=0; /* just read a 0 length packet */ - if (rr->length == 0) goto again; + if (rr->length == 0) + { + empty_record_count++; + if (empty_record_count > MAX_EMPTY_RECORDS) + { + al=SSL_AD_UNEXPECTED_MESSAGE; + SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_RECORD_TOO_SMALL); + goto f_err; + } + goto again; + } #if 0 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length); @@ -979,7 +996,7 @@ int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) if (!ssl3_setup_read_buffer(s)) return(-1); - if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) || + if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) || (peek && (type != SSL3_RT_APPLICATION_DATA))) { SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); |