Add a couple of new helper functions to BER_Decoder:

decode_and_check takes an expected value; if the decoded value does
not match, a Decoding_Error with a specified string is thrown. Useful
for checking embedded version codes.

decode_octet_string_bigint is for decoding INTEGER values that are
stored as OCTET STRINGs. Totally obnoxious and useless, but common
especially in the ECC standards.

1 files changed, 8 insertions, 0 deletions

diff --git a/src/asn1/ber_dec.cpp b/src/asn1/ber_dec.cpp
index 66a27dd4e..ea0334202 100644
--- a/src/asn1/ber_dec.cpp
+++ b/src/asn1/ber_dec.cpp
@@ -355,6 +355,14 @@ BER_Decoder& BER_Decoder::decode(BigInt& out)
    return decode(out, INTEGER, UNIVERSAL);
    }
 
+BER_Decoder& BER_Decoder::decode_octet_string_bigint(BigInt& out)
+   {
+   SecureVector<byte> out_vec;
+   decode(out_vec, OCTET_STRING);
+   out = BigInt::decode(&out_vec[0], out_vec.size());
+   return (*this);
+   }
+
 /*
 * Decode a BER encoded BOOLEAN
 */