commit 572d448ab234e8edaa3e7dc0dd95c49cf8c86382
author Hanno Becker <hanno.becker@arm.com> Tue Jul 23 13:47:53 2019 +0100
committer Hanno Becker <hanno.becker@arm.com> Mon Aug 12 17:05:03 2019 +0100
tree 6754b9d64574cc89e912c83cd52587e16d1c5f37
parent 9a12243b012493043fdda9cc4e5fc21cc5c3ac7b

Enforce NULL context for hardcoded RNG

programs/ssl/ssl_server.c

diff --git a/programs/ssl/ssl_server.c b/programs/ssl/ssl_server.c
index bf502a5..e13af91 100644
--- a/programs/ssl/ssl_server.c
+++ b/programs/ssl/ssl_server.c
@@ -97,6 +97,20 @@
 }
 #endif /* MBEDTLS_DEBUG_C */
 
+#if defined(MBEDTLS_SSL_CONF_RNG)
+int rng_wrap( void *ctx, unsigned char *dst, size_t len );
+
+mbedtls_ctr_drbg_context *rng_ctx_global = NULL;
+int rng_wrap( void *ctx, unsigned char *dst, size_t len )
+{
+    /* We expect the NULL parameter here. */
+    if( ctx != NULL )
+        return( -1 );
+
+    return( mbedtls_ctr_drbg_random( rng_ctx_global, dst, len ) );
+}
+#endif /* MBEDTLS_SSL_CONF_RNG */
+
 int main( void )
 {
     int ret, len;
@@ -212,7 +226,12 @@
         goto exit;
     }
 
+#if !defined(MBEDTLS_SSL_CONF_RNG)
     mbedtls_ssl_conf_rng( &conf, mbedtls_ctr_drbg_random, &ctr_drbg );
+#else
+    rng_ctx_global = &ctr_drbg;
+#endif
+
 #if defined(MBEDTLS_DEBUG_C)
     mbedtls_ssl_conf_dbg( &conf, my_debug, stdout );
 #endif