Fix seg fault when sending early_data using CCM ciphersuites
[openssl.git] / ssl / tls13_enc.c
index 2dc7dad..db8de1d 100644 (file)
@@ -264,9 +264,16 @@ static int derive_secret_key_and_iv(SSL *s, int send, const EVP_MD *md,
     /* TODO(size_t): convert me */
     keylen = EVP_CIPHER_key_length(ciph);
     if (EVP_CIPHER_mode(ciph) == EVP_CIPH_CCM_MODE) {
+        uint32_t algenc;
+
         ivlen = EVP_CCM_TLS_IV_LEN;
-        if (s->s3->tmp.new_cipher->algorithm_enc
-                & (SSL_AES128CCM8 | SSL_AES256CCM8))
+        if (s->s3->tmp.new_cipher == NULL) {
+            /* We've not selected a cipher yet - we must be doing early data */
+            algenc = s->session->cipher->algorithm_enc;
+        } else {
+            algenc = s->s3->tmp.new_cipher->algorithm_enc;
+        }
+        if (algenc & (SSL_AES128CCM8 | SSL_AES256CCM8))
             taglen = EVP_CCM8_TLS_TAG_LEN;
          else
             taglen = EVP_CCM_TLS_TAG_LEN;
@@ -422,6 +429,16 @@ int tls13_change_cipher_state(SSL *s, int which)
             label = client_handshake_traffic;
             labellen = sizeof(client_handshake_traffic) - 1;
             log_label = CLIENT_HANDSHAKE_LABEL;
+            /*
+             * The hanshake hash used for the server read handshake traffic
+             * secret is the same as the hash for the server write handshake
+             * traffic secret. However, if we processed early data then we delay
+             * changing the server read cipher state until later, and the
+             * handshake hashes have moved on. Therefore we use the value saved
+             * earlier when we did the server write change cipher state.
+             */
+            if (s->server)
+                hash = s->handshake_traffic_hash;
         } else {
             insecret = s->master_secret;
             label = client_application_traffic;
@@ -469,6 +486,9 @@ int tls13_change_cipher_state(SSL *s, int which)
     if (label == server_application_traffic)
         memcpy(s->server_finished_hash, hashval, hashlen);
 
+    if (s->server && label == server_handshake_traffic)
+        memcpy(s->handshake_traffic_hash, hashval, hashlen);
+
     if (label == client_application_traffic) {
         /*
          * We also create the resumption master secret, but this time use the