110 lines
4.0 KiB
Diff
110 lines
4.0 KiB
Diff
|
From 99fb785a5f85315b95288921a321a935ea29a51e Mon Sep 17 00:00:00 2001
|
||
|
From: Matt Caswell <matt@openssl.org>
|
||
|
Date: Fri, 31 May 2024 11:14:33 +0100
|
||
|
Subject: [PATCH 01/10] Fix SSL_select_next_proto
|
||
|
|
||
|
Ensure that the provided client list is non-NULL and starts with a valid
|
||
|
entry. When called from the ALPN callback the client list should already
|
||
|
have been validated by OpenSSL so this should not cause a problem. When
|
||
|
called from the NPN callback the client list is locally configured and
|
||
|
will not have already been validated. Therefore SSL_select_next_proto
|
||
|
should not assume that it is correctly formatted.
|
||
|
|
||
|
We implement stricter checking of the client protocol list. We also do the
|
||
|
same for the server list while we are about it.
|
||
|
|
||
|
CVE-2024-5535
|
||
|
|
||
|
Reviewed-by: Neil Horman <nhorman@openssl.org>
|
||
|
Reviewed-by: Tomas Mraz <tomas@openssl.org>
|
||
|
(Merged from https://github.com/openssl/openssl/pull/24717)
|
||
|
---
|
||
|
ssl/ssl_lib.c | 63 ++++++++++++++++++++++++++++++++-------------------
|
||
|
1 file changed, 40 insertions(+), 23 deletions(-)
|
||
|
|
||
|
diff --git a/ssl/ssl_lib.c b/ssl/ssl_lib.c
|
||
|
index 016135fe18..cf52b317cf 100644
|
||
|
--- a/ssl/ssl_lib.c
|
||
|
+++ b/ssl/ssl_lib.c
|
||
|
@@ -3518,37 +3518,54 @@ int SSL_select_next_proto(unsigned char **out, unsigned char *outlen,
|
||
|
unsigned int server_len,
|
||
|
const unsigned char *client, unsigned int client_len)
|
||
|
{
|
||
|
- unsigned int i, j;
|
||
|
- const unsigned char *result;
|
||
|
- int status = OPENSSL_NPN_UNSUPPORTED;
|
||
|
+ PACKET cpkt, csubpkt, spkt, ssubpkt;
|
||
|
+
|
||
|
+ if (!PACKET_buf_init(&cpkt, client, client_len)
|
||
|
+ || !PACKET_get_length_prefixed_1(&cpkt, &csubpkt)
|
||
|
+ || PACKET_remaining(&csubpkt) == 0) {
|
||
|
+ *out = NULL;
|
||
|
+ *outlen = 0;
|
||
|
+ return OPENSSL_NPN_NO_OVERLAP;
|
||
|
+ }
|
||
|
+
|
||
|
+ /*
|
||
|
+ * Set the default opportunistic protocol. Will be overwritten if we find
|
||
|
+ * a match.
|
||
|
+ */
|
||
|
+ *out = (unsigned char *)PACKET_data(&csubpkt);
|
||
|
+ *outlen = (unsigned char)PACKET_remaining(&csubpkt);
|
||
|
|
||
|
/*
|
||
|
* For each protocol in server preference order, see if we support it.
|
||
|
*/
|
||
|
- for (i = 0; i < server_len;) {
|
||
|
- for (j = 0; j < client_len;) {
|
||
|
- if (server[i] == client[j] &&
|
||
|
- memcmp(&server[i + 1], &client[j + 1], server[i]) == 0) {
|
||
|
- /* We found a match */
|
||
|
- result = &server[i];
|
||
|
- status = OPENSSL_NPN_NEGOTIATED;
|
||
|
- goto found;
|
||
|
+ if (PACKET_buf_init(&spkt, server, server_len)) {
|
||
|
+ while (PACKET_get_length_prefixed_1(&spkt, &ssubpkt)) {
|
||
|
+ if (PACKET_remaining(&ssubpkt) == 0)
|
||
|
+ continue; /* Invalid - ignore it */
|
||
|
+ if (PACKET_buf_init(&cpkt, client, client_len)) {
|
||
|
+ while (PACKET_get_length_prefixed_1(&cpkt, &csubpkt)) {
|
||
|
+ if (PACKET_equal(&csubpkt, PACKET_data(&ssubpkt),
|
||
|
+ PACKET_remaining(&ssubpkt))) {
|
||
|
+ /* We found a match */
|
||
|
+ *out = (unsigned char *)PACKET_data(&ssubpkt);
|
||
|
+ *outlen = (unsigned char)PACKET_remaining(&ssubpkt);
|
||
|
+ return OPENSSL_NPN_NEGOTIATED;
|
||
|
+ }
|
||
|
+ }
|
||
|
+ /* Ignore spurious trailing bytes in the client list */
|
||
|
+ } else {
|
||
|
+ /* This should never happen */
|
||
|
+ return OPENSSL_NPN_NO_OVERLAP;
|
||
|
}
|
||
|
- j += client[j];
|
||
|
- j++;
|
||
|
}
|
||
|
- i += server[i];
|
||
|
- i++;
|
||
|
+ /* Ignore spurious trailing bytes in the server list */
|
||
|
}
|
||
|
|
||
|
- /* There's no overlap between our protocols and the server's list. */
|
||
|
- result = client;
|
||
|
- status = OPENSSL_NPN_NO_OVERLAP;
|
||
|
-
|
||
|
- found:
|
||
|
- *out = (unsigned char *)result + 1;
|
||
|
- *outlen = result[0];
|
||
|
- return status;
|
||
|
+ /*
|
||
|
+ * There's no overlap between our protocols and the server's list. We use
|
||
|
+ * the default opportunistic protocol selected earlier
|
||
|
+ */
|
||
|
+ return OPENSSL_NPN_NO_OVERLAP;
|
||
|
}
|
||
|
|
||
|
#ifndef OPENSSL_NO_NEXTPROTONEG
|
||
|
--
|
||
|
2.46.0
|
||
|
|