pk_wrap: add a check for equal signature parts
diff --git a/library/pk_wrap.c b/library/pk_wrap.c
index 6007a23..2e22ec9 100644
--- a/library/pk_wrap.c
+++ b/library/pk_wrap.c
@@ -542,10 +542,9 @@
static int extract_ecdsa_sig( unsigned char **p, const unsigned char *end,
mbedtls_asn1_buf *sig )
{
- int ret;
- size_t len_signature;
- size_t len_partial;
- int tag_type;
+ int ret, tag_type;
+ size_t len_signature, len_partial;
+
if( ( end - *p ) < 1 )
{
return( MBEDTLS_ERR_X509_INVALID_SIGNATURE +
@@ -590,6 +589,10 @@
len_partial--;
}
+ // Check if both parts are of the same size
+ if( len_partial != len_signature )
+ return( MBEDTLS_ERR_X509_INVALID_SIGNATURE );
+
memcpy( sig->p + len_partial, *p, len_partial );
len_signature += len_partial;
sig->tag = tag_type;