strongSwan

Hi, when SIGN_ECDSA_WITH_SHAxxx_DER (and possibly other _SHAxxx_DER) signature scheme is used in combination with pkcs11 plugin, raw output of C_sign() should be asn1 encoded, otherwise signature verification fails.

This ugly patch provides proof of concept code that makes signature authentication work:

--- a/src/libstrongswan/plugins/pkcs11/pkcs11_private_key.c
+++ b/src/libstrongswan/plugins/pkcs11/pkcs11_private_key.c
@@ -24,6 +24,8 @@

 #include <utils/debug.h>

+#include <asn1/asn1.h>
+
 typedef struct private_pkcs11_private_key_t private_pkcs11_private_key_t;

 /**
@@ -288,7 +290,11 @@ METHOD(private_key_t, sign, bool,
         free(buf);
         return FALSE;
     }
-    *signature = chunk_create(buf, len);
+    if ((scheme == SIGN_ECDSA_WITH_SHA1_DER) || (scheme == SIGN_ECDSA_WITH_SHA256_DER) || (scheme == SIGN_ECDSA_WITH_SHA384_DER) || (scheme == SIGN_ECDSA_WITH_SHA512_DER)) {
+        *signature = asn1_wrap(ASN1_SEQUENCE, "mm", asn1_integer("c", chunk_create(&buf[0], len/2)), asn1_integer("c", chunk_create(&buf[len/2], len/2)));
+        free(buf);
+    } else
+        *signature = chunk_create(buf, len);
     return TRUE;
 }

Best regards
Luka