Refactor sending alert on decryption failure

Take sending of the alert outside of DecryptTls() and DecryptTls13(). The alert is now sent in ProcessReplyEx().

src/internal.c

@@ -16969,17 +16969,6 @@ static int DecryptTls(WOLFSSL* ssl, byte* plain, const byte* input, word16 sz)
     /* Reset state */
     ssl->decrypt.state = CIPHER_STATE_BEGIN;
 
-    /* handle mac error case */
-    if (ret == VERIFY_MAC_ERROR) {
-        if (!ssl->options.dtls) {
-            SendAlert(ssl, alert_fatal, bad_record_mac);
-        }
-    #ifdef WOLFSSL_DTLS_DROP_STATS
-        if (ssl->options.dtls)
-            ssl->macDropCount++;
-    #endif /* WOLFSSL_DTLS_DROP_STATS */
-    }
-
     return ret;
 }
 
@@ -18503,7 +18492,7 @@ int ProcessReplyEx(WOLFSSL* ssl, int allowSocketErr)
                                         in->buffer + in->idx,
                                         in->buffer + in->idx,
                                         ssl->curSize,
-                                        aad, aad_size, !ssl->options.dtls);
+                                        aad, aad_size);
                 #else
                         ret = DECRYPT_ERROR;
                 #endif /* WOLFSSL_TLS13 */
@@ -18534,7 +18523,7 @@ int ProcessReplyEx(WOLFSSL* ssl, int allowSocketErr)
                     /* If in DTLS mode, if the decrypt fails for any
                      * reason, pretend the datagram never happened. */
                     if (ssl->options.dtls) {
-                        WOLFSSL_MSG("DTLS: Ignoring decrypted failed record");
+                        WOLFSSL_MSG("DTLS: Ignoring failed decryption");
                         ssl->options.processReply = doProcessInit;
                         ssl->buffers.inputBuffer.idx =
                                         ssl->buffers.inputBuffer.length;
@@ -18567,13 +18556,16 @@ int ProcessReplyEx(WOLFSSL* ssl, int allowSocketErr)
                                 return 0;
                             }
                             WOLFSSL_MSG("Too much EarlyData!");
+                            SendAlert(ssl, alert_fatal, unexpected_message);
+                            WOLFSSL_ERROR(TOO_MUCH_EARLY_DATA);
+                            return TOO_MUCH_EARLY_DATA;
                         }
                     }
                 #endif
                     SendAlert(ssl, alert_fatal, bad_record_mac);
                     /* Push error once we know that we will error out here */
                     WOLFSSL_ERROR(ret);
-                    return DECRYPT_ERROR;
+                    return ret;
                 }
             }
 

src/sniffer.c

@@ -4790,7 +4790,7 @@ static const byte* DecryptMessage(WOLFSSL* ssl, const byte* input, word32 sz,
 
 #ifdef WOLFSSL_TLS13
     if (IsAtLeastTLSv1_3(ssl->version)) {
-        ret = DecryptTls13(ssl, output, input, sz, (byte*)rh, RECORD_HEADER_SZ, 0);
+        ret = DecryptTls13(ssl, output, input, sz, (byte*)rh, RECORD_HEADER_SZ);
     }
     else
 #endif

src/tls13.c

@@ -2278,11 +2278,10 @@ static int Tls13IntegrityOnly_Decrypt(WOLFSSL* ssl, byte* output,
  * sz      The length of the encrypted data plus authentication tag.
  * aad     The additional authentication data.
  * aadSz   The size of the addition authentication data.
- * doAlert Generate alert on error (set to 0 for sniffer use cases)
  * returns 0 on success, otherwise failure.
  */
 int DecryptTls13(WOLFSSL* ssl, byte* output, const byte* input, word16 sz,
-                 const byte* aad, word16 aadSz, int doAlert)
+                 const byte* aad, word16 aadSz)
 {
     int    ret    = 0;
     word16 dataSz = sz - ssl->specs.aead_mac_size;
@@ -2477,17 +2476,6 @@ int DecryptTls13(WOLFSSL* ssl, byte* output, const byte* input, word16 sz,
             break;
     }
 
-#ifndef WOLFSSL_EARLY_DATA
-    if (ret < 0) {
-        if (doAlert) {
-            SendAlert(ssl, alert_fatal, bad_record_mac);
-        }
-        ret = VERIFY_MAC_ERROR;
-    }
-#else
-    (void)doAlert;
-#endif
-
     return ret;
 }
 

wolfssl/internal.h

@@ -1867,8 +1867,7 @@ WOLFSSL_LOCAL int ChachaAEADEncrypt(WOLFSSL* ssl, byte* out, const byte* input,
 
 #ifdef WOLFSSL_TLS13
 WOLFSSL_LOCAL int  DecryptTls13(WOLFSSL* ssl, byte* output, const byte* input,
-                                word16 sz, const byte* aad, word16 aadSz,
+                                word16 sz, const byte* aad, word16 aadSz);
-                                int doAlert);
 WOLFSSL_LOCAL int  DoTls13HandShakeMsgType(WOLFSSL* ssl, byte* input,
                                            word32* inOutIdx, byte type,
                                            word32 size, word32 totalSz);