net/quic/crypto/channel_id_openssl.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "net/quic/crypto/channel_id.h"
   6
   7 #include <openssl/bn.h>
   8 #include <openssl/ec.h>
   9 #include <openssl/ecdsa.h>
  10 #include <openssl/obj_mac.h>
  11 #include <openssl/sha.h>
  12
  13 #include "crypto/openssl_util.h"
  14 #include "crypto/scoped_openssl_types.h"
  15
  16 using base::StringPiece;
  17
  18 namespace net {
  19
  20 // static
  21 bool ChannelIDVerifier::Verify(StringPiece key,
  22                                StringPiece signed_data,
  23                                StringPiece signature) {
  24   return VerifyRaw(key, signed_data, signature, true);
  25 }
  26
  27 // static
  28 bool ChannelIDVerifier::VerifyRaw(StringPiece key,
  29                                   StringPiece signed_data,
  30                                   StringPiece signature,
  31                                   bool is_channel_id_signature) {
  32   if (key.size() != 32 * 2 ||
  33       signature.size() != 32 * 2) {
  34     return false;
  35   }
  36
  37   crypto::ScopedEC_GROUP p256(EC_GROUP_new_by_curve_name(NID_X9_62_prime256v1));
  38   if (!p256) {
  39     return false;
  40   }
  41
  42   crypto::ScopedBIGNUM x(BN_new()), y(BN_new()), r(BN_new()), s(BN_new());
  43
  44   ECDSA_SIG sig;
  45   sig.r = r.get();
  46   sig.s = s.get();
  47
  48   const uint8* key_bytes = reinterpret_cast<const uint8*>(key.data());
  49   const uint8* signature_bytes =
  50       reinterpret_cast<const uint8*>(signature.data());
  51
  52   if (BN_bin2bn(key_bytes       +  0, 32, x.get()) == nullptr ||
  53       BN_bin2bn(key_bytes       + 32, 32, y.get()) == nullptr ||
  54       BN_bin2bn(signature_bytes +  0, 32, sig.r) == nullptr ||
  55       BN_bin2bn(signature_bytes + 32, 32, sig.s) == nullptr) {
  56     return false;
  57   }
  58
  59   crypto::ScopedEC_POINT point(EC_POINT_new(p256.get()));
  60   if (!point ||
  61       !EC_POINT_set_affine_coordinates_GFp(p256.get(), point.get(), x.get(),
  62                                            y.get(), nullptr)) {
  63     return false;
  64   }
  65
  66   crypto::ScopedEC_KEY ecdsa_key(EC_KEY_new());
  67   if (ecdsa_key.get() == nullptr ||
  68       !EC_KEY_set_group(ecdsa_key.get(), p256.get()) ||
  69       !EC_KEY_set_public_key(ecdsa_key.get(), point.get())) {
  70     return false;
  71   }
  72
  73   SHA256_CTX sha256;
  74   SHA256_Init(&sha256);
  75   if (is_channel_id_signature) {
  76     SHA256_Update(&sha256, kContextStr, strlen(kContextStr) + 1);
  77     SHA256_Update(&sha256, kClientToServerStr, strlen(kClientToServerStr) + 1);
  78   }
  79   SHA256_Update(&sha256, signed_data.data(), signed_data.size());
  80
  81   unsigned char digest[SHA256_DIGEST_LENGTH];
  82   SHA256_Final(digest, &sha256);
  83
  84   return ECDSA_do_verify(digest, sizeof(digest), &sig, ecdsa_key.get()) == 1;
  85 }
  86
  87 }  // namespace net