1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
|
// 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/cert/jwk_serializer.h"
#include <cert.h>
#include <keyhi.h>
#include <nss.h>
#include "base/base64.h"
#include "base/values.h"
#include "crypto/nss_util.h"
#include "crypto/scoped_nss_types.h"
namespace net {
namespace JwkSerializer {
namespace {
bool ConvertEcPrime256v1PublicKeyInfoToJwk(
CERTSubjectPublicKeyInfo* spki,
base::DictionaryValue* public_key_jwk) {
static const int kUncompressedEncodingType = 4;
static const int kPrime256v1PublicKeyLength = 64;
// The public key value is encoded as 0x04 + 64 bytes of public key.
// NSS gives the length as the bit length.
if (spki->subjectPublicKey.len != (kPrime256v1PublicKeyLength + 1) * 8 ||
spki->subjectPublicKey.data[0] != kUncompressedEncodingType)
return false;
public_key_jwk->SetString("kty", "EC");
public_key_jwk->SetString("crv", "P-256");
base::StringPiece x(
reinterpret_cast<char*>(spki->subjectPublicKey.data + 1),
kPrime256v1PublicKeyLength / 2);
std::string x_b64;
base::Base64Encode(x, &x_b64);
public_key_jwk->SetString("x", x_b64);
base::StringPiece y(
reinterpret_cast<char*>(spki->subjectPublicKey.data + 1 +
kPrime256v1PublicKeyLength / 2),
kPrime256v1PublicKeyLength / 2);
std::string y_b64;
base::Base64Encode(y, &y_b64);
public_key_jwk->SetString("y", y_b64);
return true;
}
bool ConvertEcPublicKeyInfoToJwk(
CERTSubjectPublicKeyInfo* spki,
base::DictionaryValue* public_key_jwk) {
// 1.2.840.10045.3.1.7
// (iso.member-body.us.ansi-x9-62.ellipticCurve.primeCurve.prime256v1)
// (This includes the DER-encoded type (OID) and length: parameters can be
// anything, so the DER type isn't implied, and NSS includes it.)
static const unsigned char kPrime256v1[] = {
0x06, 0x08, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x03, 0x01, 0x07
};
if (spki->algorithm.parameters.len == sizeof(kPrime256v1) &&
!memcmp(spki->algorithm.parameters.data, kPrime256v1,
sizeof(kPrime256v1))) {
return ConvertEcPrime256v1PublicKeyInfoToJwk(spki, public_key_jwk);
}
// TODO(juanlang): other curves
return false;
}
typedef scoped_ptr<
CERTSubjectPublicKeyInfo,
crypto::NSSDestroyer<CERTSubjectPublicKeyInfo,
SECKEY_DestroySubjectPublicKeyInfo> >
ScopedCERTSubjectPublicKeyInfo;
} // namespace
bool ConvertSpkiFromDerToJwk(
const base::StringPiece& spki_der,
base::DictionaryValue* public_key_jwk) {
public_key_jwk->Clear();
crypto::EnsureNSSInit();
if (!NSS_IsInitialized())
return false;
SECItem sec_item;
sec_item.data = const_cast<unsigned char*>(
reinterpret_cast<const unsigned char*>(spki_der.data()));
sec_item.len = spki_der.size();
ScopedCERTSubjectPublicKeyInfo spki(
SECKEY_DecodeDERSubjectPublicKeyInfo(&sec_item));
if (!spki)
return false;
// 1.2.840.10045.2
// (iso.member-body.us.ansi-x9-62.id-ecPublicKey)
// (This omits the ASN.1 encoding of the type (OID) and length: the fact that
// this is an OID is already clear, and NSS omits it here.)
static const unsigned char kIdEcPublicKey[] = {
0x2A, 0x86, 0x48, 0xCE, 0x3D, 0x02, 0x01
};
bool rv = false;
if (spki->algorithm.algorithm.len == sizeof(kIdEcPublicKey) &&
!memcmp(spki->algorithm.algorithm.data, kIdEcPublicKey,
sizeof(kIdEcPublicKey))) {
rv = ConvertEcPublicKeyInfoToJwk(spki.get(), public_key_jwk);
}
// TODO(juanlang): other algorithms
return rv;
}
} // namespace JwkSerializer
} // namespace net
|
