From 1c47d35a0380783b62004a7cb8058d34e082f8d5 Mon Sep 17 00:00:00 2001 From: Matt Caswell Date: Mon, 6 Nov 2017 16:52:06 +0000 Subject: [PATCH] Mark a zero length record as read If SSL_read() is called with a zero length buffer, and we read a zero length record then we should mark that record as read. Reviewed-by: Rich Salz (Merged from https://github.com/openssl/openssl/pull/4685) --- ssl/record/rec_layer_s3.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/ssl/record/rec_layer_s3.c b/ssl/record/rec_layer_s3.c index 980e5a4b8b..d10b91b24f 100644 --- a/ssl/record/rec_layer_s3.c +++ b/ssl/record/rec_layer_s3.c @@ -1305,8 +1305,16 @@ int ssl3_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf, if (recvd_type != NULL) *recvd_type = SSL3_RECORD_get_type(rr); - if (len == 0) + if (len == 0) { + /* + * Mark a zero length record as read. This ensures multiple calls to + * SSL_read() with a zero length buffer will eventually cause + * SSL_pending() to report data as being available. + */ + if (SSL3_RECORD_get_length(rr) == 0) + SSL3_RECORD_set_read(rr); return 0; + } totalbytes = 0; do {