src/third_party/WebKit/Source/modules/crypto/Key.cpp

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  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/KeyAlgorithm.h"
  37 #include "platform/CryptoResult.h"
  38 #include "public/platform/WebCryptoAlgorithmParams.h"
  39 #include "public/platform/WebString.h"
  40
  41 namespace WebCore {
  42
  43 namespace {
  44
  45 const char* keyTypeToString(blink::WebCryptoKeyType type)
  46 {
  47     switch (type) {
  48     case blink::WebCryptoKeyTypeSecret:
  49         return "secret";
  50     case blink::WebCryptoKeyTypePublic:
  51         return "public";
  52     case blink::WebCryptoKeyTypePrivate:
  53         return "private";
  54     }
  55     ASSERT_NOT_REACHED();
  56     return 0;
  57 }
  58
  59 struct KeyUsageMapping {
  60     blink::WebCryptoKeyUsage value;
  61     const char* const name;
  62 };
  63
  64 // The order of this array is the same order that will appear in Key.usages. It
  65 // must be kept ordered as described by the Web Crypto spec.
  66 const KeyUsageMapping keyUsageMappings[] = {
  67     { blink::WebCryptoKeyUsageEncrypt, "encrypt" },
  68     { blink::WebCryptoKeyUsageDecrypt, "decrypt" },
  69     { blink::WebCryptoKeyUsageSign, "sign" },
  70     { blink::WebCryptoKeyUsageVerify, "verify" },
  71     { blink::WebCryptoKeyUsageDeriveKey, "deriveKey" },
  72     { blink::WebCryptoKeyUsageDeriveBits, "deriveBits" },
  73     { blink::WebCryptoKeyUsageWrapKey, "wrapKey" },
  74     { blink::WebCryptoKeyUsageUnwrapKey, "unwrapKey" },
  75 };
  76
  77 COMPILE_ASSERT(blink::EndOfWebCryptoKeyUsage == (1 << 7) + 1, update_keyUsageMappings);
  78
  79 const char* keyUsageToString(blink::WebCryptoKeyUsage usage)
  80 {
  81     for (size_t i = 0; i < WTF_ARRAY_LENGTH(keyUsageMappings); ++i) {
  82         if (keyUsageMappings[i].value == usage)
  83             return keyUsageMappings[i].name;
  84     }
  85     ASSERT_NOT_REACHED();
  86     return 0;
  87 }
  88
  89 blink::WebCryptoKeyUsageMask keyUsageStringToMask(const String& usageString)
  90 {
  91     for (size_t i = 0; i < WTF_ARRAY_LENGTH(keyUsageMappings); ++i) {
  92         if (keyUsageMappings[i].name == usageString)
  93             return keyUsageMappings[i].value;
  94     }
  95     return 0;
  96 }
  97
  98 blink::WebCryptoKeyUsageMask toKeyUsage(AlgorithmOperation operation)
  99 {
 100     switch (operation) {
 101     case Encrypt:
 102         return blink::WebCryptoKeyUsageEncrypt;
 103     case Decrypt:
 104         return blink::WebCryptoKeyUsageDecrypt;
 105     case Sign:
 106         return blink::WebCryptoKeyUsageSign;
 107     case Verify:
 108         return blink::WebCryptoKeyUsageVerify;
 109     case DeriveKey:
 110         return blink::WebCryptoKeyUsageDeriveKey;
 111     case DeriveBits:
 112         return blink::WebCryptoKeyUsageDeriveBits;
 113     case WrapKey:
 114         return blink::WebCryptoKeyUsageWrapKey;
 115     case UnwrapKey:
 116         return blink::WebCryptoKeyUsageUnwrapKey;
 117     case Digest:
 118     case GenerateKey:
 119     case ImportKey:
 120         break;
 121     }
 122
 123     ASSERT_NOT_REACHED();
 124     return 0;
 125 }
 126
 127 } // namespace
 128
 129 Key::~Key()
 130 {
 131 }
 132
 133 Key::Key(const blink::WebCryptoKey& key)
 134     : m_key(key)
 135 {
 136     ScriptWrappable::init(this);
 137 }
 138
 139 String Key::type() const
 140 {
 141     return keyTypeToString(m_key.type());
 142 }
 143
 144 bool Key::extractable() const
 145 {
 146     return m_key.extractable();
 147 }
 148
 149 KeyAlgorithm* Key::algorithm()
 150 {
 151     if (!m_algorithm)
 152         m_algorithm = KeyAlgorithm::create(m_key.algorithm());
 153     return m_algorithm.get();
 154 }
 155
 156 // FIXME: This creates a new javascript array each time. What should happen
 157 //        instead is return the same (immutable) array. (Javascript callers can
 158 //        distinguish this by doing an == test on the arrays and seeing they are
 159 //        different).
 160 Vector<String> Key::usages() const
 161 {
 162     Vector<String> result;
 163     for (size_t i = 0; i < WTF_ARRAY_LENGTH(keyUsageMappings); ++i) {
 164         blink::WebCryptoKeyUsage usage = keyUsageMappings[i].value;
 165         if (m_key.usages() & usage)
 166             result.append(keyUsageToString(usage));
 167     }
 168     return result;
 169 }
 170
 171 bool Key::canBeUsedForAlgorithm(const blink::WebCryptoAlgorithm& algorithm, AlgorithmOperation op, CryptoResult* result) const
 172 {
 173     if (!(m_key.usages() & toKeyUsage(op))) {
 174         result->completeWithError(blink::WebCryptoErrorTypeInvalidAccess, "key.usages does not permit this operation");
 175         return false;
 176     }
 177
 178     if (m_key.algorithm().id() != algorithm.id()) {
 179         result->completeWithError(blink::WebCryptoErrorTypeInvalidAccess, "key.algorithm does not match that of operation");
 180         return false;
 181     }
 182
 183     return true;
 184 }
 185
 186 bool Key::parseFormat(const String& formatString, blink::WebCryptoKeyFormat& format, CryptoResult* result)
 187 {
 188     // There are few enough values that testing serially is fast enough.
 189     if (formatString == "raw") {
 190         format = blink::WebCryptoKeyFormatRaw;
 191         return true;
 192     }
 193     if (formatString == "pkcs8") {
 194         format = blink::WebCryptoKeyFormatPkcs8;
 195         return true;
 196     }
 197     if (formatString == "spki") {
 198         format = blink::WebCryptoKeyFormatSpki;
 199         return true;
 200     }
 201     if (formatString == "jwk") {
 202         format = blink::WebCryptoKeyFormatJwk;
 203         return true;
 204     }
 205
 206     result->completeWithError(blink::WebCryptoErrorTypeSyntax, "Invalid keyFormat argument");
 207     return false;
 208 }
 209
 210 bool Key::parseUsageMask(const Vector<String>& usages, blink::WebCryptoKeyUsageMask& mask, CryptoResult* result)
 211 {
 212     mask = 0;
 213     for (size_t i = 0; i < usages.size(); ++i) {
 214         blink::WebCryptoKeyUsageMask usage = keyUsageStringToMask(usages[i]);
 215         if (!usage) {
 216             result->completeWithError(blink::WebCryptoErrorTypeSyntax, "Invalid keyUsages argument");
 217             return false;
 218         }
 219         mask |= usage;
 220     }
 221     return true;
 222 }
 223
 224 void Key::trace(Visitor* visitor)
 225 {
 226     visitor->trace(m_algorithm);
 227 }
 228
 229 } // namespace WebCore