Add specific SSL error code for unexpected CIDs
Currently, the stack silently ignores DTLS frames with an unexpected CID.
However, in a system which performs CID-based demultiplexing before passing
datagrams to the Mbed TLS stack, unexpected CIDs are a sign of something not
working properly, and users might want to know about it.
This commit introduces an SSL error code MBEDTLS_ERR_SSL_UNEXPECTED_CID
which the stack can return in response to an unexpected CID. It will
conditionally be put to use in subsequent commits.
diff --git a/library/error.c b/library/error.c
index 608423b..e401a84 100644
--- a/library/error.c
+++ b/library/error.c
@@ -523,6 +523,8 @@
mbedtls_snprintf( buf, buflen, "SSL - The asynchronous operation is not completed yet" );
if( use_ret == -(MBEDTLS_ERR_SSL_EARLY_MESSAGE) )
mbedtls_snprintf( buf, buflen, "SSL - Internal-only message signaling that a message arrived early" );
+ if( use_ret == -(MBEDTLS_ERR_SSL_UNEXPECTED_CID) )
+ mbedtls_snprintf( buf, buflen, "SSL - An encrypted DTLS-frame with an unexpected CID was received" );
if( use_ret == -(MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS) )
mbedtls_snprintf( buf, buflen, "SSL - A cryptographic operation is in progress. Try again later" );
#endif /* MBEDTLS_SSL_TLS_C */