OpenSSL/NSS implementation of ProofVerfifier.

net/quic/crypto/proof_verifier_chromium.cc

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/quic/crypto/proof_verifier_chromium.h"
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/callback_helpers.h"
+#include "base/compiler_specific.h"
+#include "base/logging.h"
+#include "base/strings/stringprintf.h"
+#include "crypto/signature_verifier.h"
+#include "net/base/net_errors.h"
+#include "net/base/net_log.h"
+#include "net/cert/asn1_util.h"
+#include "net/cert/cert_status_flags.h"
+#include "net/cert/cert_verifier.h"
+#include "net/cert/cert_verify_result.h"
+#include "net/cert/single_request_cert_verifier.h"
+#include "net/cert/x509_certificate.h"
+#include "net/cert/x509_util.h"
+#include "net/quic/crypto/crypto_protocol.h"
+#include "net/ssl/ssl_config_service.h"
+
+using base::StringPiece;
+using base::StringPrintf;
+using std::string;
+using std::vector;
+
+namespace net {
+
+ProofVerifierChromium::ProofVerifierChromium(CertVerifier* cert_verifier,
+                                             const BoundNetLog& net_log)
+  : cert_verifier_(cert_verifier),
+    error_details_(NULL),
+    next_state_(STATE_NONE),
+    net_log_(net_log) {
+}
+
+ProofVerifierChromium::~ProofVerifierChromium() {
+  verifier_.reset();
+
+  // Reset object state.
+  callback_.Reset();
+  cert_verify_result_.Reset();

[wtc, 2013/07/03 00:20:26]

Just wanted to point out that these two are not necessary in a destructor.
They are just defensive programming.

verifier_.reset(), however, is necessary to abort a pending CertVerifier
request.

[ramant (doing other things), 2013/07/03 05:46:34]

Done.

+}
+
+int ProofVerifierChromium::VerifyProof(const string& hostname,
+                                       const string& server_config,
+                                       const vector<string>& certs,
+                                       const string& signature,
+                                       std::string* error_details,
+                                       const CompletionCallback& callback) {
+  DCHECK(error_details);
+  error_details->clear();
+
+  DCHECK_EQ(STATE_NONE, next_state_);
+  if (STATE_NONE != next_state_) {
+    *error_details = "Certificate is already set and VerifyProof has begun";
+    DLOG(WARNING) << *error_details;
+    return ERR_FAILED;
+  }
+
+  if (certs.empty()) {
+    *error_details = "Failed to create certificate chain. Certs are empty.";
+    DLOG(WARNING) << *error_details;
+    return ERR_FAILED;
+  }
+
+  // Convert certs to X509Certificate.
+  vector<StringPiece> cert_pieces(certs.size());
+  for (unsigned i = 0; i < certs.size(); i++) {
+    cert_pieces[i] = base::StringPiece(certs[i]);
+  }
+  cert_ = X509Certificate::CreateFromDERCertChain(cert_pieces);
+  if (!cert_.get()) {
+    cert_verify_result_.Reset();
+    cert_verify_result_.cert_status = CERT_STATUS_INVALID;

[wtc, 2013/07/03 00:20:26]

Ah, I missed this earlier. Since cert_verify_result_ is for internal use,
we don't need to set cert_verify_result_.cert_status before returning
ERR_FAILED.

[ramant (doing other things), 2013/07/03 05:46:34]

Done.

+    *error_details = "Failed to create certificate chain";
+    DLOG(WARNING) << *error_details;
+    return ERR_FAILED;
+  }
+
+  // We call VerifySignature first to avoid copying of server_config and
+  // signature.
+  if (!VerifySignature(server_config, signature, certs[0])) {
+    *error_details = "Failed to verify signature of server config";
+    DLOG(WARNING) << *error_details;
+    return ERR_FAILED;
+  }
+
+  hostname_ = hostname;
+  callback_ = callback;
+  error_details_ = error_details;
+
+  next_state_ = STATE_VERIFY_CERT;
+  return DoLoop(OK);
+}
+
+int ProofVerifierChromium::DoLoop(int last_result) {
+  int rv = last_result;
+  do {
+    State state = next_state_;
+    next_state_ = STATE_NONE;
+    switch (state) {
+      case STATE_VERIFY_CERT:
+        DCHECK(rv == OK);
+        rv = DoVerifyCert(rv);
+        break;
+      case STATE_VERIFY_CERT_COMPLETE:
+        rv = DoVerifyCertComplete(rv);
+        break;
+      case STATE_NONE:
+      default:
+        rv = ERR_UNEXPECTED;
+        LOG(DFATAL) << "unexpected state " << state;
+        break;
+    }
+  } while (rv != ERR_IO_PENDING && next_state_ != STATE_NONE);
+  return rv;
+}
+
+void ProofVerifierChromium::OnIOComplete(int result) {
+  int rv = DoLoop(result);
+  if (rv != ERR_IO_PENDING) {
+    base::ResetAndReturn(&callback_).Run(rv);
+  }
+}
+
+int ProofVerifierChromium::DoVerifyCert(int result) {
+  next_state_ = STATE_VERIFY_CERT_COMPLETE;
+
+  int flags = 0;

[wtc, 2013/07/03 00:20:26]

Just wanted to make sure you want |flags| to be 0.

[ramant (doing other things), 2013/07/03 05:46:34]

Did it per agl's comments.

+  verifier_.reset(new SingleRequestCertVerifier(cert_verifier_));
+  return verifier_->Verify(
+      cert_.get(),
+      hostname_,
+      flags,
+      SSLConfigService::GetCRLSet().get(),
+      &cert_verify_result_,
+      base::Bind(&ProofVerifierChromium::OnIOComplete,
+                 base::Unretained(this)),
+      net_log_);
+}
+
+int ProofVerifierChromium::DoVerifyCertComplete(int result) {
+  verifier_.reset();
+
+  if (result <= ERR_FAILED) {
+    *error_details_ = StringPrintf("Failed to verify certificate chain: %s",
+                                  ErrorToString(result));

[wtc, 2013/07/03 00:20:26]

Nit: indentation is off by one.

[ramant (doing other things), 2013/07/03 05:46:34]

Done.

+    DLOG(WARNING) << *error_details_;
+    result = ERR_FAILED;
+  }
+
+  // Exit DoLoop and return the result to the caller to VerifyProof.
+  DCHECK_EQ(STATE_NONE, next_state_);
+  return result;
+}
+
+bool ProofVerifierChromium::VerifySignature(const string& signed_data,
+                                            const string& signature,
+                                            const string& cert) {
+  StringPiece spki;
+  if (!asn1::ExtractSPKIFromDERCert(cert, &spki)) {
+    DLOG(WARNING) << "ExtractSPKIFromDERCert failed";
+    return false;
+  }
+
+  crypto::SignatureVerifier verifier;
+
+  size_t size_bits;
+  X509Certificate::PublicKeyType type;
+  X509Certificate::GetPublicKeyInfo(cert_->os_cert_handle(), &size_bits,
+                                    &type);
+  if (type == X509Certificate::kPublicKeyTypeRSA) {
+    crypto::SignatureVerifier::HashAlgorithm hash_alg =
+        crypto::SignatureVerifier::SHA256;
+    crypto::SignatureVerifier::HashAlgorithm mask_hash_alg = hash_alg;
+    unsigned int hash_len = 32;  // 32 is the length of a SHA-256 hash.
+    // TODO(wtc): change this to hash_len when we can change the wire format.
+    unsigned int salt_len = signature.size() - hash_len - 2;
+
+    bool ok = verifier.VerifyInitRSAPSS(
+        hash_alg, mask_hash_alg, salt_len,
+        reinterpret_cast<const uint8*>(signature.data()), signature.size(),
+        reinterpret_cast<const uint8*>(spki.data()), spki.size());
+    if (!ok) {
+      DLOG(WARNING) << "VerifyInitRSAPSS failed";
+      return false;
+    }
+  } else if (type == X509Certificate::kPublicKeyTypeECDSA) {
+    // This is the algorithm ID for ECDSA with SHA-256. Parameters are ABSENT.
+    // RFC 5758:
+    //   ecdsa-with-SHA256 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
+    //        us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 2 }
+    //   ...
+    //   When the ecdsa-with-SHA224, ecdsa-with-SHA256, ecdsa-with-SHA384, or
+    //   ecdsa-with-SHA512 algorithm identifier appears in the algorithm field
+    //   as an AlgorithmIdentifier, the encoding MUST omit the parameters
+    //   field.  That is, the AlgorithmIdentifier SHALL be a SEQUENCE of one
+    //   component, the OID ecdsa-with-SHA224, ecdsa-with-SHA256, ecdsa-with-
+    //   SHA384, or ecdsa-with-SHA512.
+    // See also RFC 5480, Appendix A.
+    static const uint8 kECDSAWithSHA256AlgorithmID[] = {
+      0x30, 0x0a,
+        0x06, 0x08,
+          0x2a, 0x86, 0x48, 0xce, 0x3d, 0x04, 0x03, 0x02,
+    };
+
+    if (!verifier.VerifyInit(
+            kECDSAWithSHA256AlgorithmID, sizeof(kECDSAWithSHA256AlgorithmID),
+            reinterpret_cast<const uint8*>(signature.data()),
+            signature.size(),
+            reinterpret_cast<const uint8*>(spki.data()),
+            spki.size())) {
+      DLOG(WARNING) << "VerifyInit failed";
+      return false;
+    }
+  } else {
+    LOG(ERROR) << "Unsupported public key type " << type;
+    return false;
+  }
+
+  verifier.VerifyUpdate(reinterpret_cast<const uint8*>(kProofSignatureLabel),
+                        sizeof(kProofSignatureLabel));
+  verifier.VerifyUpdate(reinterpret_cast<const uint8*>(signed_data.data()),
+                        signed_data.size());
+
+  if (!verifier.VerifyFinal()) {
+    DLOG(WARNING) << "VerifyFinal failed";
+    return false;
+  }
+
+  DLOG(INFO) << "VerifyFinal success";
+  return true;
+}
+
+}  // namespace net