1 /*
2 * Copyright (C) 2013 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 * * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include "config.h"
32 #include "modules/crypto/Key.h"
33
34 #include "bindings/v8/ExceptionState.h"
35 #include "core/dom/ExceptionCode.h"
36 #include "modules/crypto/Algorithm.h"
37 #include "public/platform/WebCryptoAlgorithmParams.h"
38
39 namespace WebCore {
40
41 namespace {
42
keyTypeToString(blink::WebCryptoKeyType type)43 const char* keyTypeToString(blink::WebCryptoKeyType type)
44 {
45 switch (type) {
46 case blink::WebCryptoKeyTypeSecret:
47 return "secret";
48 case blink::WebCryptoKeyTypePublic:
49 return "public";
50 case blink::WebCryptoKeyTypePrivate:
51 return "private";
52 }
53 ASSERT_NOT_REACHED();
54 return 0;
55 }
56
57 struct KeyUsageMapping {
58 blink::WebCryptoKeyUsage value;
59 const char* const name;
60 };
61
62 // Keep this array sorted.
63 const KeyUsageMapping keyUsageMappings[] = {
64 { blink::WebCryptoKeyUsageDecrypt, "decrypt" },
65 { blink::WebCryptoKeyUsageDeriveKey, "deriveKey" },
66 { blink::WebCryptoKeyUsageEncrypt, "encrypt" },
67 { blink::WebCryptoKeyUsageSign, "sign" },
68 { blink::WebCryptoKeyUsageUnwrapKey, "unwrapKey" },
69 { blink::WebCryptoKeyUsageVerify, "verify" },
70 { blink::WebCryptoKeyUsageWrapKey, "wrapKey" },
71 };
72
73 COMPILE_ASSERT(blink::EndOfWebCryptoKeyUsage == (1 << 6) + 1, update_keyUsageMappings);
74
keyUsageToString(blink::WebCryptoKeyUsage usage)75 const char* keyUsageToString(blink::WebCryptoKeyUsage usage)
76 {
77 for (size_t i = 0; i < WTF_ARRAY_LENGTH(keyUsageMappings); ++i) {
78 if (keyUsageMappings[i].value == usage)
79 return keyUsageMappings[i].name;
80 }
81 ASSERT_NOT_REACHED();
82 return 0;
83 }
84
keyUsageStringToMask(const String & usageString)85 blink::WebCryptoKeyUsageMask keyUsageStringToMask(const String& usageString)
86 {
87 for (size_t i = 0; i < WTF_ARRAY_LENGTH(keyUsageMappings); ++i) {
88 if (keyUsageMappings[i].name == usageString)
89 return keyUsageMappings[i].value;
90 }
91 return 0;
92 }
93
toKeyUsage(AlgorithmOperation operation)94 blink::WebCryptoKeyUsageMask toKeyUsage(AlgorithmOperation operation)
95 {
96 switch (operation) {
97 case Encrypt:
98 return blink::WebCryptoKeyUsageEncrypt;
99 case Decrypt:
100 return blink::WebCryptoKeyUsageDecrypt;
101 case Sign:
102 return blink::WebCryptoKeyUsageSign;
103 case Verify:
104 return blink::WebCryptoKeyUsageVerify;
105 case DeriveKey:
106 return blink::WebCryptoKeyUsageDeriveKey;
107 case WrapKey:
108 return blink::WebCryptoKeyUsageWrapKey;
109 case UnwrapKey:
110 return blink::WebCryptoKeyUsageUnwrapKey;
111 case Digest:
112 case GenerateKey:
113 case ImportKey:
114 break;
115 }
116
117 ASSERT_NOT_REACHED();
118 return 0;
119 }
120
getHmacHashId(const blink::WebCryptoAlgorithm & algorithm,blink::WebCryptoAlgorithmId & hashId)121 bool getHmacHashId(const blink::WebCryptoAlgorithm& algorithm, blink::WebCryptoAlgorithmId& hashId)
122 {
123 if (algorithm.hmacParams()) {
124 hashId = algorithm.hmacParams()->hash().id();
125 return true;
126 }
127 if (algorithm.hmacKeyParams()) {
128 hashId = algorithm.hmacKeyParams()->hash().id();
129 return true;
130 }
131 return false;
132 }
133
134 } // namespace
135
~Key()136 Key::~Key()
137 {
138 }
139
Key(const blink::WebCryptoKey & key)140 Key::Key(const blink::WebCryptoKey& key)
141 : m_key(key)
142 {
143 ScriptWrappable::init(this);
144 }
145
type() const146 String Key::type() const
147 {
148 return keyTypeToString(m_key.type());
149 }
150
extractable() const151 bool Key::extractable() const
152 {
153 return m_key.extractable();
154 }
155
algorithm()156 Algorithm* Key::algorithm()
157 {
158 if (!m_algorithm)
159 m_algorithm = Algorithm::create(m_key.algorithm());
160 return m_algorithm.get();
161 }
162
163 // FIXME: This creates a new javascript array each time. What should happen
164 // instead is return the same (immutable) array. (Javascript callers can
165 // distinguish this by doing an == test on the arrays and seeing they are
166 // different).
usages() const167 Vector<String> Key::usages() const
168 {
169 Vector<String> result;
170 for (size_t i = 0; i < WTF_ARRAY_LENGTH(keyUsageMappings); ++i) {
171 blink::WebCryptoKeyUsage usage = keyUsageMappings[i].value;
172 if (m_key.usages() & usage)
173 result.append(keyUsageToString(usage));
174 }
175 return result;
176 }
177
canBeUsedForAlgorithm(const blink::WebCryptoAlgorithm & algorithm,AlgorithmOperation op,ExceptionState & exceptionState) const178 bool Key::canBeUsedForAlgorithm(const blink::WebCryptoAlgorithm& algorithm, AlgorithmOperation op, ExceptionState& exceptionState) const
179 {
180 if (!(m_key.usages() & toKeyUsage(op))) {
181 exceptionState.throwDOMException(NotSupportedError, "key.usages does not permit this operation");
182 return false;
183 }
184
185 if (m_key.algorithm().id() != algorithm.id()) {
186 exceptionState.throwDOMException(NotSupportedError, "key.algorithm does not match that of operation");
187 return false;
188 }
189
190 // Verify that the algorithm-specific parameters for the key conform to the
191 // algorithm.
192 // FIXME: Verify that this is complete.
193
194 if (m_key.algorithm().id() == blink::WebCryptoAlgorithmIdHmac) {
195 blink::WebCryptoAlgorithmId keyHash;
196 blink::WebCryptoAlgorithmId algorithmHash;
197 if (!getHmacHashId(m_key.algorithm(), keyHash) || !getHmacHashId(algorithm, algorithmHash) || keyHash != algorithmHash) {
198 exceptionState.throwDOMException(NotSupportedError, "key.algorithm does not match that of operation (HMAC's hash differs)");
199 return false;
200 }
201 }
202
203 return true;
204 }
205
parseFormat(const String & formatString,blink::WebCryptoKeyFormat & format,ExceptionState & exceptionState)206 bool Key::parseFormat(const String& formatString, blink::WebCryptoKeyFormat& format, ExceptionState& exceptionState)
207 {
208 // There are few enough values that testing serially is fast enough.
209 if (formatString == "raw") {
210 format = blink::WebCryptoKeyFormatRaw;
211 return true;
212 }
213 if (formatString == "pkcs8") {
214 format = blink::WebCryptoKeyFormatPkcs8;
215 return true;
216 }
217 if (formatString == "spki") {
218 format = blink::WebCryptoKeyFormatSpki;
219 return true;
220 }
221 if (formatString == "jwk") {
222 format = blink::WebCryptoKeyFormatJwk;
223 return true;
224 }
225
226 exceptionState.throwTypeError("Invalid keyFormat argument");
227 return false;
228 }
229
parseUsageMask(const Vector<String> & usages,blink::WebCryptoKeyUsageMask & mask,ExceptionState & exceptionState)230 bool Key::parseUsageMask(const Vector<String>& usages, blink::WebCryptoKeyUsageMask& mask, ExceptionState& exceptionState)
231 {
232 mask = 0;
233 for (size_t i = 0; i < usages.size(); ++i) {
234 blink::WebCryptoKeyUsageMask usage = keyUsageStringToMask(usages[i]);
235 if (!usage) {
236 exceptionState.throwTypeError("Invalid keyUsages argument");
237 return false;
238 }
239 mask |= usage;
240 }
241 return true;
242 }
243
244 } // namespace WebCore
245