session tickets: Use sizeof() for the various fields

Signed-off-by: NKurt Roeckx <kurt@roeckx.be>
Reviewed-by: NMatt Caswell <matt@openssl.org>

GH: #515, MR: #2153

ssl/s3_lib.c

@@ -3395,20 +3395,32 @@ long ssl3_ctx_ctrl(SSL_CTX *ctx, int cmd, long larg, void *parg)
     case SSL_CTRL_GET_TLSEXT_TICKET_KEYS:
         {
             unsigned char *keys = parg;
+            long tlsext_tick_keylen = (sizeof(ctx->tlsext_tick_key_name) +
+                sizeof(ctx->tlsext_tick_hmac_key) + (ctx->tlsext_tick_aes_key));
             if (!keys)
-                return 48;
-            if (larg != 48) {
+                return tlsext_tick_keylen;
+            if (larg != tlsext_tick_keylen) {
                 SSLerr(SSL_F_SSL3_CTX_CTRL, SSL_R_INVALID_TICKET_KEYS_LENGTH);
                 return 0;
             }
             if (cmd == SSL_CTRL_SET_TLSEXT_TICKET_KEYS) {
-                memcpy(ctx->tlsext_tick_key_name, keys, 16);
-                memcpy(ctx->tlsext_tick_hmac_key, keys + 16, 16);
-                memcpy(ctx->tlsext_tick_aes_key, keys + 32, 16);
+                memcpy(ctx->tlsext_tick_key_name, keys,
+                       sizeof(ctx->tlsext_tick_key_name));
+                memcpy(ctx->tlsext_tick_hmac_key,
+                       keys + sizeof(ctx->tlsext_tick_key_name),
+                       sizeof(ctx->tlsext_tick_hmac_key));
+                memcpy(ctx->tlsext_tick_aes_key,
+                       keys + sizeof(ctx->tlsext_tick_key_name) + sizeof(ctx->tlsext_tick_hmac_key),
+                       sizeof(ctx->tlsext_tick_aes_key));
             } else {
-                memcpy(keys, ctx->tlsext_tick_key_name, 16);
-                memcpy(keys + 16, ctx->tlsext_tick_hmac_key, 16);
-                memcpy(keys + 32, ctx->tlsext_tick_aes_key, 16);
+                memcpy(keys, ctx->tlsext_tick_key_name,
+                       sizeof(ctx->tlsext_tick_key_name));
+                memcpy(keys + sizeof(ctx->tlsext_tick_key_name),
+                       ctx->tlsext_tick_hmac_key,
+                       sizeof(ctx->tlsext_tick_hmac_key));
+                memcpy(keys + sizeof(ctx->tlsext_tick_key_name) + sizeof(ctx->tlsext_tick_hmac_key),
+                       ctx->tlsext_tick_aes_key,
+                       sizeof(ctx->tlsext_tick_aes_key));
             }
             return 1;
         }

ssl/ssl_lib.c

@@ -2461,10 +2461,10 @@ SSL_CTX *SSL_CTX_new(const SSL_METHOD *meth)
     ret->max_send_fragment = SSL3_RT_MAX_PLAIN_LENGTH;
     ret->split_send_fragment = SSL3_RT_MAX_PLAIN_LENGTH;
 
-    /* Setup RFC4507 ticket keys */
-    if ((RAND_bytes(ret->tlsext_tick_key_name, 16) <= 0)
-        || (RAND_bytes(ret->tlsext_tick_hmac_key, 16) <= 0)
-        || (RAND_bytes(ret->tlsext_tick_aes_key, 16) <= 0))
+    /* Setup RFC5077 ticket keys */
+    if ((RAND_bytes(ret->tlsext_tick_key_name, sizeof(ret->tlsext_tick_key_name)) <= 0)
+        || (RAND_bytes(ret->tlsext_tick_hmac_key, sizeof(ret->tlsext_tick_hmac_key)) <= 0)
+        || (RAND_bytes(ret->tlsext_tick_aes_key, sizeof(ret->tlsext_tick_aes_key)) <= 0))
         ret->options |= SSL_OP_NO_TICKET;
 
 #ifndef OPENSSL_NO_SRP

ssl/statem/statem_srvr.c

@@ -3051,10 +3051,12 @@ int tls_construct_new_session_ticket(SSL *s)
         if (!EVP_EncryptInit_ex(ctx, EVP_aes_128_cbc(), NULL,
                                 tctx->tlsext_tick_aes_key, iv))
             goto err;
-        if (!HMAC_Init_ex(hctx, tctx->tlsext_tick_hmac_key, 16,
+        if (!HMAC_Init_ex(hctx, tctx->tlsext_tick_hmac_key,
+                          sizeof(tctx->tlsext_tick_hmac_key),
                           EVP_sha256(), NULL))
             goto err;
-        memcpy(key_name, tctx->tlsext_tick_key_name, 16);
+        memcpy(key_name, tctx->tlsext_tick_key_name,
+               sizeof(tctx->tlsext_tick_key_name));
     }
 
     /*

ssl/t1_lib.c

@@ -3129,15 +3129,17 @@ static int tls_decrypt_ticket(SSL *s, const unsigned char *etick,
             renew_ticket = 1;
     } else {
         /* Check key name matches */
-        if (memcmp(etick, tctx->tlsext_tick_key_name, 16)) {
+        if (memcmp(etick, tctx->tlsext_tick_key_name,
+                   sizeof(tctx->tlsext_tick_key_name)) != 0) {
             ret = 2;
             goto err;
         }
-        if (HMAC_Init_ex(hctx, tctx->tlsext_tick_hmac_key, 16,
+        if (HMAC_Init_ex(hctx, tctx->tlsext_tick_hmac_key,
+                         sizeof(tctx->tlsext_tick_hmac_key),
                          EVP_sha256(), NULL) <= 0
                 || EVP_DecryptInit_ex(ctx, EVP_aes_128_cbc(), NULL,
                                       tctx->tlsext_tick_aes_key,
-                                      etick + 16) <= 0) {
+                                      etick + sizeof(tctx->tlsext_tick_key_name)) <= 0) {
             goto err;
        }
     }