signed_exchange_signature_verifier.cc

// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/web_package/signed_exchange_signature_verifier.h"

#include <array>
#include <string>
#include <string_view>
#include <vector>

#include "base/containers/span.h"
#include "base/format_macros.h"
#include "base/metrics/histogram_macros.h"
#include "base/numerics/byte_conversions.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/time/time.h"
#include "base/trace_event/trace_event.h"
#include "content/browser/web_package/signed_exchange_certificate_chain.h"
#include "content/browser/web_package/signed_exchange_consts.h"
#include "content/browser/web_package/signed_exchange_envelope.h"
#include "content/browser/web_package/signed_exchange_signature_header_field.h"
#include "content/browser/web_package/signed_exchange_utils.h"
#include "content/public/browser/content_browser_client.h"
#include "crypto/signature_verifier.h"
#include "net/cert/asn1_util.h"
#include "net/cert/x509_util.h"
#include "third_party/boringssl/src/include/openssl/bytestring.h"
#include "third_party/boringssl/src/include/openssl/ec.h"
#include "third_party/boringssl/src/include/openssl/ec_key.h"
#include "third_party/boringssl/src/include/openssl/evp.h"

namespace content {

namespace {

// https://wicg.github.io/webpackage/draft-yasskin-http-origin-signed-responses.html#signature-validity
// Step 5. "Let message be the concatenation of the following byte strings."
constexpr uint8_t kMessageHeader[] = …// 5.1. "A string that consists of octet 32 (0x20) repeated 64 times."
    // [spec text]
    "\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20"
    "\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20"
    "\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20"
    "\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20"
    // 5.2. "A context string: the ASCII encoding of "HTTP Exchange 1"." ...
    // "but implementations of drafts MUST NOT use it and MUST use another
    // draft-specific string beginning with "HTTP Exchange 1 " instead."
    // [spec text]
    // 5.3. "A single 0 byte which serves as a separator." [spec text]
    "HTTP Exchange 1 b3";

constexpr base::TimeDelta kOneWeek = …;
constexpr base::TimeDelta kFourWeeks = …;

std::optional<crypto::SignatureVerifier::SignatureAlgorithm>
GetSignatureAlgorithm(scoped_refptr<net::X509Certificate> cert,
                      SignedExchangeDevToolsProxy* devtools_proxy) { … }

bool VerifySignature(base::span<const uint8_t> sig,
                     base::span<const uint8_t> msg,
                     scoped_refptr<net::X509Certificate> cert,
                     crypto::SignatureVerifier::SignatureAlgorithm algorithm,
                     SignedExchangeDevToolsProxy* devtools_proxy) { … }

std::string HexDump(const std::vector<uint8_t>& msg) { … }

void AppendToBuf8BytesBigEndian(std::vector<uint8_t>* buf, uint64_t n) { … }

std::vector<uint8_t> GenerateSignedMessage(
    SignedExchangeVersion version,
    const SignedExchangeEnvelope& envelope) { … }

base::Time TimeFromSignedExchangeUnixTime(uint64_t t) { … }

SignedExchangeSignatureVerifier::Result VerifyValidityPeriod(
    const SignedExchangeEnvelope& envelope) { … }

// Implements "Signature validity" of
// https://wicg.github.io/webpackage/draft-yasskin-httpbis-origin-signed-exchanges-impl.html#signature-validity
SignedExchangeSignatureVerifier::Result VerifyTimestamps(
    const SignedExchangeEnvelope& envelope,
    const base::Time& verification_time) { … }

}  // namespace

SignedExchangeSignatureVerifier::Result SignedExchangeSignatureVerifier::Verify(
    SignedExchangeVersion version,
    const SignedExchangeEnvelope& envelope,
    const SignedExchangeCertificateChain* cert_chain,
    const base::Time& verification_time,
    SignedExchangeDevToolsProxy* devtools_proxy) { … }

}  // namespace content
chromium/content/browser/web_package/signed_exchange_signature_verifier.cc
