WebCrypto: Add framework for AlgorithmIdentifier normalization.

public/platform/WebCryptoAlgorithmParams.h

+/*
+ * Copyright (C) 2013 Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
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+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
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+ * in the documentation and/or other materials provided with the
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+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef WebCryptoAlgorithmParams_h
+#define WebCryptoAlgorithmParams_h
+
+#include "WebCommon.h"
+#include "WebCryptoAlgorithm.h"
+
+namespace WebKit {
+
+// Base class for all the algorithm parameters.
+//
+// NOTE: For documentation on the meaning of each of the parameters see the Web
+//       Crypto spec. Parameters have the same name (minus "WebCrypto" prefix).

[abarth-chromium, 2013/07/02 06:46:36]

Please add a link to the spec.

[eroman, 2013/07/02 08:12:27]

Done.

+class WebCryptoAlgorithmParams {
+public:
+    WebCryptoAlgorithmParams(WebCryptoAlgorithmParamsType type)
+        : m_type(type)
+    {
+    }
+
+    virtual ~WebCryptoAlgorithmParams() { }
+
+    WebCryptoAlgorithmParamsType type() const { return m_type; }
+
+protected:
+    // Helper class for a chunk of owned immutable data.

[abarth-chromium, 2013/07/02 06:46:36]

We should be able to just use WebVector

[eroman, 2013/07/02 08:12:27]

Done.

+    class Bytes {
+    public:
+        // Makes a copy of |data|.
+        Bytes(const unsigned char*, size_t);
+        ~Bytes();
+
+        const unsigned char* data() const { return m_data; }
+        size_t size() const { return m_size; }
+
+    private:
+        Bytes(const Bytes&);
+        Bytes& operator=(const Bytes&);
+
+        const unsigned char* m_data;
+        size_t m_size;
+    };
+
+private:
+    WebCryptoAlgorithmParamsType m_type;
+};
+
+class WebCryptoAesCbcParams : public WebCryptoAlgorithmParams {
+public:
+    WebCryptoAesCbcParams(unsigned char* iv, size_t ivSize)
+        : WebCryptoAlgorithmParams(AesCbcParams)
+        , m_iv(iv, ivSize)
+    {
+    }
+
+    // The initialization vector. MUST be 16 bytes.

[abarth-chromium, 2013/07/02 06:46:36]

Can you enforce that with an ASSERT rather than a comment?  Comments can be
incorrect, but ASSERTs are verified by tests.

[eroman, 2013/07/02 08:12:27]

Removed the comment.

I had copy-pasted it from the W3C document, and forgot to delete.

No assert is necessary, since the guarantee is handled by
NormalizeAlgorithm.cpp, and tested for explicitly by the layouttest.

+    const unsigned char* iv() const { return m_iv.data(); }
+    size_t ivSize() const { return m_iv.size(); }
+
+private:
+    const Bytes m_iv;
+};
+
+class WebCryptoAesKeyGenParams : public WebCryptoAlgorithmParams {
+public:
+    WebCryptoAesKeyGenParams(unsigned short length)
+        : WebCryptoAlgorithmParams(AesKeyGenParams)
+        , m_length(length)
+    {
+    }
+
+    // The length, in bits, of the key.
+    unsigned short length() const { return m_length; }
+
+private:
+    const unsigned short m_length;
+};
+
+} // namespace WebKit
+
+#endif