gecko-dev/dom/webauthn/WebAuthnUtil.cpp

132 строки
3.5 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/dom/WebAuthnUtil.h"
#include "pkixutil.h"
namespace mozilla {
namespace dom {
nsresult
ReadToCryptoBuffer(pkix::Reader& aSrc, /* out */ CryptoBuffer& aDest,
uint32_t aLen)
{
if (aSrc.EnsureLength(aLen) != pkix::Success) {
return NS_ERROR_DOM_UNKNOWN_ERR;
}
aDest.ClearAndRetainStorage();
for (uint32_t offset = 0; offset < aLen; ++offset) {
uint8_t b;
if (aSrc.Read(b) != pkix::Success) {
return NS_ERROR_DOM_UNKNOWN_ERR;
}
if (!aDest.AppendElement(b, mozilla::fallible)) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
return NS_OK;
}
nsresult
U2FAssembleAuthenticatorData(/* out */ CryptoBuffer& aAuthenticatorData,
const CryptoBuffer& aRpIdHash,
const CryptoBuffer& aSignatureData)
{
// The AuthenticatorData for U2F devices is the concatenation of the
// RP ID with the output of the U2F Sign operation.
if (aRpIdHash.Length() != 32) {
return NS_ERROR_INVALID_ARG;
}
if (!aAuthenticatorData.AppendElements(aRpIdHash, mozilla::fallible)) {
return NS_ERROR_OUT_OF_MEMORY;
}
if (!aAuthenticatorData.AppendElements(aSignatureData, mozilla::fallible)) {
return NS_ERROR_OUT_OF_MEMORY;
}
return NS_OK;
}
nsresult
U2FDecomposeRegistrationResponse(const CryptoBuffer& aResponse,
/* out */ CryptoBuffer& aPubKeyBuf,
/* out */ CryptoBuffer& aKeyHandleBuf,
/* out */ CryptoBuffer& aAttestationCertBuf,
/* out */ CryptoBuffer& aSignatureBuf)
{
// U2F v1.1 Format via
// http://fidoalliance.org/specs/fido-u2f-v1.1-id-20160915/fido-u2f-raw-message-formats-v1.1-id-20160915.html
//
// Bytes Value
// 1 0x05
// 65 public key
// 1 key handle length
// * key handle
// ASN.1 attestation certificate
// * attestation signature
pkix::Input u2fResponse;
u2fResponse.Init(aResponse.Elements(), aResponse.Length());
pkix::Reader input(u2fResponse);
uint8_t b;
if (input.Read(b) != pkix::Success) {
return NS_ERROR_DOM_UNKNOWN_ERR;
}
if (b != 0x05) {
return NS_ERROR_DOM_UNKNOWN_ERR;
}
nsresult rv = ReadToCryptoBuffer(input, aPubKeyBuf, 65);
if (NS_FAILED(rv)) {
return rv;
}
uint8_t handleLen;
if (input.Read(handleLen) != pkix::Success) {
return NS_ERROR_DOM_UNKNOWN_ERR;
}
rv = ReadToCryptoBuffer(input, aKeyHandleBuf, handleLen);
if (NS_FAILED(rv)) {
return rv;
}
// We have to parse the ASN.1 SEQUENCE on the outside to determine the cert's
// length.
pkix::Input cert;
if (pkix::der::ExpectTagAndGetValue(input, pkix::der::SEQUENCE, cert)
!= pkix::Success) {
return NS_ERROR_DOM_UNKNOWN_ERR;
}
pkix::Reader certInput(cert);
rv = ReadToCryptoBuffer(certInput, aAttestationCertBuf, cert.GetLength());
if (NS_FAILED(rv)) {
return rv;
}
// The remainder of u2fResponse is the signature
pkix::Input u2fSig;
input.SkipToEnd(u2fSig);
pkix::Reader sigInput(u2fSig);
rv = ReadToCryptoBuffer(sigInput, aSignatureBuf, u2fSig.GetLength());
if (NS_FAILED(rv)) {
return rv;
}
return NS_OK;
}
}
}