CCM*: Add implementation
diff --git a/library/ccm.c b/library/ccm.c
index cf65209..b195a71 100644
--- a/library/ccm.c
+++ b/library/ccm.c
@@ -154,7 +154,13 @@
* 'length' checked later (when writing it to the first block)
*/
if( tag_len < 4 || tag_len > 16 || tag_len % 2 != 0 )
- return( MBEDTLS_ERR_CCM_BAD_INPUT );
+ {
+ /*
+ * Loosen the requirements to enable support for CCM* (IEEE 802.15.4)
+ */
+ if( tag_len != 0 )
+ return( MBEDTLS_ERR_CCM_BAD_INPUT );
+ }
/* Also implies q is within bounds */
if( iv_len < 7 || iv_len > 13 )
@@ -302,7 +308,7 @@
/*
* Authenticated encryption
*/
-int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
+int mbedtls_ccm_star_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
const unsigned char *iv, size_t iv_len,
const unsigned char *add, size_t add_len,
const unsigned char *input, unsigned char *output,
@@ -312,10 +318,23 @@
add, add_len, input, output, tag, tag_len ) );
}
+int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
+ const unsigned char *iv, size_t iv_len,
+ const unsigned char *add, size_t add_len,
+ const unsigned char *input, unsigned char *output,
+ unsigned char *tag, size_t tag_len )
+{
+ if( tag_len == 0 )
+ return( MBEDTLS_ERR_CCM_BAD_INPUT );
+
+ return( mbedtls_ccm_star_encrypt_and_tag( ctx, length, iv, iv_len, add,
+ add_len, input, output, tag, tag_len ) );
+}
+
/*
* Authenticated decryption
*/
-int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
+int mbedtls_ccm_star_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
const unsigned char *iv, size_t iv_len,
const unsigned char *add, size_t add_len,
const unsigned char *input, unsigned char *output,
@@ -346,6 +365,18 @@
return( 0 );
}
+int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
+ const unsigned char *iv, size_t iv_len,
+ const unsigned char *add, size_t add_len,
+ const unsigned char *input, unsigned char *output,
+ const unsigned char *tag, size_t tag_len )
+{
+ if( tag_len == 0 )
+ return( MBEDTLS_ERR_CCM_BAD_INPUT );
+
+ return( mbedtls_ccm_star_auth_decrypt( ctx, length, iv, iv_len, add,
+ add_len, input, output, tag, tag_len ) );
+}
#endif /* !MBEDTLS_CCM_ALT */
#if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)