commit 1226590c888917cb6cb9ec2546f46d2a85f5deda
author Gabor Mezei <gabor.mezei@arm.com> Mon May 09 16:43:21 2022 +0200
committer Gabor Mezei <gabor.mezei@arm.com> Wed May 11 14:29:18 2022 +0200
tree 1e3f028b103c7c6df56c77ec03106daf7c72622e
parent 15b95a6c5276729e5929e9117afad204c538bd93

Explicitly set invalid value for the end of the signiture algorithm set

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>

library/ssl_tls12_server.c

diff --git a/library/ssl_tls12_server.c b/library/ssl_tls12_server.c
index 6d07e26..14dc8e1 100644
--- a/library/ssl_tls12_server.c
+++ b/library/ssl_tls12_server.c
@@ -1632,13 +1632,14 @@
         uint16_t *set = ssl->handshake->received_sig_algs;
         const uint16_t sig_algs[] = {
             MBEDTLS_SSL_SIG_ALG_SET( MBEDTLS_SSL_HASH_SHA1 )
-            MBEDTLS_TLS_SIG_NONE
         };
+        const uint16_t invalid_sig_alg = MBEDTLS_TLS_SIG_NONE;
         size_t count = sizeof( sig_algs ) / sizeof( sig_algs[0] );
 
-        if( count <= MBEDTLS_RECEIVED_SIG_ALGS_SIZE )
+        if( count < MBEDTLS_RECEIVED_SIG_ALGS_SIZE )
         {
             memcpy( set, sig_algs, sizeof( sig_algs ) );
+            memcpy( &set[count], &invalid_sig_alg, sizeof( sig_algs[0] ) );
         }
         else
         {
@@ -1647,7 +1648,7 @@
 
             memcpy( set, sig_algs, size );
             memcpy( &set[MBEDTLS_RECEIVED_SIG_ALGS_SIZE - 1],
-                    &sig_algs[count - 1], sizeof( sig_algs[0] ) );
+                    &invalid_sig_alg, sizeof( sig_algs[0] ) );
         }
     }