Added KeyChain::selfVerifyData.
diff --git a/ndn-cpp/key-chain.cpp b/ndn-cpp/key-chain.cpp
index 1da6f9d..fc656c0 100644
--- a/ndn-cpp/key-chain.cpp
+++ b/ndn-cpp/key-chain.cpp
@@ -126,8 +126,7 @@
// TODO: use RSA_size to get the proper size of the signature buffer.
unsigned char signature[1000];
unsigned int signatureLength;
- const unsigned char *keyPointer = privateKeyDer;
- RSA *privateKey = d2i_RSAPrivateKey(NULL, &keyPointer, privateKeyDerLength);
+ RSA *privateKey = d2i_RSAPrivateKey(NULL, &privateKeyDer, privateKeyDerLength);
if (!privateKey)
throw std::runtime_error("Error decoding private key in d2i_RSAPrivateKey");
int success = RSA_sign(NID_sha256, dataFieldsDigest, sizeof(dataFieldsDigest), signature, &signatureLength, privateKey);
@@ -144,4 +143,40 @@
sign(data, DEFAULT_PUBLIC_KEY_DER, sizeof(DEFAULT_PUBLIC_KEY_DER), DEFAULT_PRIVATE_KEY_DER, sizeof(DEFAULT_PRIVATE_KEY_DER));
}
+bool KeyChain::selfVerifyData(const unsigned char *input, unsigned int inputLength, WireFormat &wireFormat)
+{
+ // Decode the data packet and digest the data fields.
+ Data data;
+ unsigned int signedFieldsBeginOffset, signedFieldsEndOffset;
+ wireFormat.decodeData(data, input, inputLength, &signedFieldsBeginOffset, &signedFieldsEndOffset);
+ if (data.getSignature().getDigestAlgorithm().size() != 0)
+ // TODO: Allow a non-default digest algorithm.
+ throw std::runtime_error("Cannot verify a data packet with a non-default digest algorithm");
+ unsigned char dataFieldsDigest[SHA256_DIGEST_LENGTH];
+ digestSha256(input + signedFieldsBeginOffset, signedFieldsEndOffset - signedFieldsBeginOffset, dataFieldsDigest);
+
+ // Find the public key.
+ const unsigned char *publicKeyDer;
+ unsigned int publicKeyDerLength;
+ if (data.getSignedInfo().getKeyLocator().getType() == ndn_KeyLocatorType_KEY) {
+ publicKeyDer = &data.getSignedInfo().getKeyLocator().getKeyOrCertificate().front();
+ publicKeyDerLength = data.getSignedInfo().getKeyLocator().getKeyOrCertificate().size();
+ }
+ else
+ // Can't find a public key.
+ return false;
+
+ // Verify the dataFieldsDigest.
+ RSA *publicKey = d2i_RSA_PUBKEY(NULL, &publicKeyDer, publicKeyDerLength);
+ if (!publicKey)
+ throw std::runtime_error("Error decoding public key in d2i_RSAPublicKey");
+ int success = RSA_verify
+ (NID_sha256, dataFieldsDigest, sizeof(dataFieldsDigest), &data.getSignature().getSignature().front(),
+ data.getSignature().getSignature().size(), publicKey);
+ // Free the public key before checking for success.
+ RSA_free(publicKey);
+
+ return (success == 1);
+}
+
}