avoid -Wstringop-overflow when buiding with gcc11
Signed-off-by: Shawn Carey <shawn.carey@netfoundry.io>
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index c749a86..a00b439 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -6364,8 +6364,6 @@
#if defined(MBEDTLS_SHA512_C)
-typedef int (*finish_sha384_t)(mbedtls_sha512_context*, unsigned char*);
-
static void ssl_calc_finished_tls_sha384(
mbedtls_ssl_context *ssl, unsigned char *buf, int from )
{
@@ -6373,12 +6371,6 @@
const char *sender;
mbedtls_sha512_context sha512;
unsigned char padbuf[48];
- /*
- * For SHA-384, we can save 16 bytes by keeping padbuf 48 bytes long.
- * However, to avoid stringop-overflow warning in gcc, we have to cast
- * mbedtls_sha512_finish_ret().
- */
- finish_sha384_t finish_sha384 = (finish_sha384_t)mbedtls_sha512_finish_ret;
mbedtls_ssl_session *session = ssl->session_negotiate;
if( !session )
@@ -6404,8 +6396,19 @@
sender = ( from == MBEDTLS_SSL_IS_CLIENT )
? "client finished"
: "server finished";
-
- finish_sha384( &sha512, padbuf );
+ /* mbedtls_sha512_finish_ret's output parameter is declared as a
+ * 64-byte buffer, but sice we're using SHA-384, we know that the
+ * output fits in 48 bytes. This is correct C, but GCC 11.1 warns
+ * about it.
+ */
+#if defined(__GNUC__) && __GNUC__ >= 11
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wstringop-overflow"
+#endif
+ mbedtls_sha512_finish_ret( &sha512, padbuf );
+#if defined(__GNUC__) && __GNUC__ >= 11
+#pragma GCC diagnostic pop
+#endif
ssl->handshake->tls_prf( session->master, 48, sender,
padbuf, 48, buf, len );