Bug 1422669 - Part4 - Kill string16 and replace with our SHA1 implementation. r=gerald

The reason explained in patch Part1 of Bug 1214018 and I just copy the reason below.

GetRawMachineId was returning its generated data through a 'string16', which on
Windows was conveniently equivalent to a std::wstring.

However on Mac, wstring uses 32-bit characters, so in order to comply with the
string16 interface, a lot of non-trivial code would have to be imported and
vetted.

Also, in the end GMPLoader::Load passes this string16 to SHA256_Update() as a
sequence of bytes, the actual type of the data is lost!

So to simplify this work, GetRawMachineId will now return its data through a
vector of bytes, and the platform-dependent implementations may use whatever
data type they want internally.

The Windows GetRawMachineId actually returns the same data in this vector, so
it stays compatible with the previous code.

MozReview-Commit-ID: 7xYgjndXWDX

--HG--
extra : rebase_source : 6a46bd7f06d6e4bc10bb98b600e7e5bc14c136ce

dom/media/gmp/rlz/lib/machine_id.cc

@@ -6,11 +6,15 @@
 
 #include <stddef.h>
 
-#include "base/sha1.h"
 #include "rlz/lib/assert.h"
 #include "rlz/lib/crc8.h"
 #include "rlz/lib/string_utils.h"
 
+// Note: The original machine_id.cc code depends on Chromium's sha1 implementation.
+// Using Mozilla's implmentation as replacement to reduce the dependency of
+// some external files.
+#include "mozilla/SHA1.h"
+
 namespace rlz_lib {
 
 bool GetMachineId(std::string* machine_id) {
@@ -24,12 +28,12 @@ bool GetMachineId(std::string* machine_id) {
     return true;
   }
 
-  base::string16 sid_string;
+  std::vector<uint8_t> sid_bytes;
   int volume_id;
-  if (!GetRawMachineId(&sid_string, &volume_id))
+  if (!GetRawMachineId(&sid_bytes, &volume_id))
     return false;
 
-  if (!testing::GetMachineIdImpl(sid_string, volume_id, machine_id))
+  if (!testing::GetMachineIdImpl(sid_bytes, volume_id, machine_id))
     return false;
 
   calculated = true;
@@ -39,40 +43,43 @@ bool GetMachineId(std::string* machine_id) {
 
 namespace testing {
 
-bool GetMachineIdImpl(const base::string16& sid_string,
+bool GetMachineIdImpl(const std::vector<uint8_t>& sid_bytes,
                       int volume_id,
                       std::string* machine_id) {
   machine_id->clear();
 
   // The ID should be the SID hash + the Hard Drive SNo. + checksum byte.
-  static const int kSizeWithoutChecksum = base::kSHA1Length + sizeof(int);
+  static const int kSizeWithoutChecksum = mozilla::SHA1Sum::kHashSize + sizeof(int);
   std::basic_string<unsigned char> id_binary(kSizeWithoutChecksum + 1, 0);
 
-  if (!sid_string.empty()) {
+  if (!sid_bytes.empty()) {
     // In order to be compatible with the old version of RLZ, the hash of the
     // SID must be done with all the original bytes from the unicode string.
     // However, the chromebase SHA1 hash function takes only an std::string as
     // input, so the unicode string needs to be converted to std::string
     // "as is".
-    size_t byte_count = sid_string.size() * sizeof(base::string16::value_type);
+    size_t byte_count = sid_bytes.size() * sizeof(std::vector<uint8_t>::value_type);
-    const char* buffer = reinterpret_cast<const char*>(sid_string.c_str());
+    const char* buffer = reinterpret_cast<const char*>(sid_bytes.data());
-    std::string sid_string_buffer(buffer, byte_count);
 
     // Note that digest can have embedded nulls.
-    std::string digest(base::SHA1HashString(sid_string_buffer));
+    mozilla::SHA1Sum SHA1;
-    VERIFY(digest.size() == base::kSHA1Length);
+    mozilla::SHA1Sum::Hash hash;
+    SHA1.update(buffer, byte_count);
+    SHA1.finish(hash);
+    std::string digest(reinterpret_cast<char*>(hash), mozilla::SHA1Sum::kHashSize);
+    VERIFY(digest.size() == mozilla::SHA1Sum::kHashSize);
     std::copy(digest.begin(), digest.end(), id_binary.begin());
   }
 
   // Convert from int to binary (makes big-endian).
   for (size_t i = 0; i < sizeof(int); i++) {
     int shift_bits = 8 * (sizeof(int) - i - 1);
-    id_binary[base::kSHA1Length + i] = static_cast<unsigned char>(
+    id_binary[mozilla::SHA1Sum::kHashSize + i] = static_cast<unsigned char>(
         (volume_id >> shift_bits) & 0xFF);
   }
 
   // Append the checksum byte.
-  if (!sid_string.empty() || (0 != volume_id))
+  if (!sid_bytes.empty() || (0 != volume_id))
     rlz_lib::Crc8::Generate(id_binary.c_str(),
                             kSizeWithoutChecksum,
                             &id_binary[kSizeWithoutChecksum]);

dom/media/gmp/rlz/lib/machine_id.h

@@ -23,7 +23,7 @@ bool GetMachineId(std::string* machine_id);
 bool GetRawMachineId(std::vector<uint8_t>* data, int* more_data);
 
 namespace testing {
-bool GetMachineIdImpl(const base::string16& sid_string,
+bool GetMachineIdImpl(const std::vector<uint8_t>& sid_bytes,
                       int volume_id,
                       std::string* machine_id);
 }  // namespace testing

dom/media/gmp/rlz/moz.build

@@ -11,6 +11,8 @@ FINAL_LIBRARY = 'xul'
 
 if CONFIG['OS_TARGET'] in ['WINNT', 'Darwin']:
     UNIFIED_SOURCES += [
+        'lib/crc8.cc',
+        'lib/machine_id.cc',
         'lib/string_utils.cc',
     ]