Implement SHA-256 fingerprint support

net/base/x509_cert_types.h

Index: net/base/x509_cert_types.h
===================================================================
--- net/base/x509_cert_types.h	(revision 155029)
+++ net/base/x509_cert_types.h	(working copy)
@@ -11,6 +11,7 @@
 #include <string>
 #include <vector>
 
+#include "base/logging.h"
 #include "base/string_piece.h"
 #include "build/build_config.h"
 #include "net/base/net_export.h"
@@ -28,32 +29,84 @@
 class X509Certificate;
 
 // SHA-1 fingerprint (160 bits) of a certificate.
-struct NET_EXPORT SHA1Fingerprint {
-  bool Equals(const SHA1Fingerprint& other) const {
+struct NET_EXPORT SHA1HashValue {
+  bool Equals(const SHA1HashValue& other) const {
     return memcmp(data, other.data, sizeof(data)) == 0;
   }
 
   unsigned char data[20];
 };
 
-// In the future there will be a generic Fingerprint type, with at least two
-// implementations: SHA1 and SHA256. See http://crbug.com/117914. Until that
-// work is done (in a separate patch) this typedef bridges the gap.
-typedef SHA1Fingerprint Fingerprint;
+class NET_EXPORT SHA1HashValueLessThan {
+ public:
+  bool operator()(const SHA1HashValue& lhs,
+                  const SHA1HashValue& rhs) const {
+    return memcmp(lhs.data, rhs.data, sizeof(lhs.data)) < 0;
+  }
+};
 
-typedef std::vector<Fingerprint> FingerprintVector;
+struct NET_EXPORT SHA256HashValue {
+  bool Equals(const SHA256HashValue& other) const {
+    return memcmp(data, other.data, sizeof(data)) == 0;
+  }
 
-class NET_EXPORT SHA1FingerprintLessThan {
+  unsigned char data[32];
+};
+
+class NET_EXPORT SHA256HashValueLessThan {
  public:
-  bool operator() (const SHA1Fingerprint& lhs,
-                   const SHA1Fingerprint& rhs) const {
+  bool operator()(const SHA256HashValue& lhs,
+                  const SHA256HashValue& rhs) const {
     return memcmp(lhs.data, rhs.data, sizeof(lhs.data)) < 0;
   }
 };
 
+enum HashValueTag {
+  HASH_VALUE_SHA1,
+  HASH_VALUE_SHA256,
+
+  // This must always be last.
+  HASH_VALUE_TAGS_COUNT
+};
+
+class NET_EXPORT HashValue {
+ public:
+  explicit HashValue(HashValueTag tag) : tag(tag) {}
+  HashValue() : tag(HASH_VALUE_SHA1) {}
+
+  bool Equals(const HashValue& other) const;
+  size_t size() const;
+  unsigned char* data();
+  const unsigned char* data() const;
+
+  HashValueTag tag;
+
+ private:
+  union {
+    SHA1HashValue sha1;
+    SHA256HashValue sha256;
+  } fingerprint;
+};
+
+class NET_EXPORT HashValueLessThan {
+ public:
+  bool operator()(const HashValue& lhs,
+                  const HashValue& rhs) const {
+    size_t lhs_size = lhs.size();
+    size_t rhs_size = rhs.size();
+
+    if (lhs_size != rhs_size)
+      return lhs_size < rhs_size;
+
+    return memcmp(lhs.data(), rhs.data(), lhs_size) < 0;
+  }
+};
+
+typedef std::vector<HashValue> HashValueVector;
+
 // IsSHA1HashInSortedArray returns true iff |hash| is in |array|, a sorted
 // array of SHA1 hashes.
-bool NET_EXPORT IsSHA1HashInSortedArray(const SHA1Fingerprint& hash,
+bool NET_EXPORT IsSHA1HashInSortedArray(const SHA1HashValue& hash,
                                         const uint8* array,
                                         size_t array_byte_len);
 
@@ -130,10 +183,10 @@
 
  private:
   // The set of fingerprints of allowed certificates.
-  std::set<SHA1Fingerprint, SHA1FingerprintLessThan> allowed_;
+  std::set<SHA1HashValue, SHA1HashValueLessThan> allowed_;
 
   // The set of fingerprints of denied certificates.
-  std::set<SHA1Fingerprint, SHA1FingerprintLessThan> denied_;
+  std::set<SHA1HashValue, SHA1HashValueLessThan> denied_;
 };
 
 #if defined(OS_MACOSX) && !defined(OS_IOS)