Index: net/cert/ct_ev_whitelist.cc |
diff --git a/net/cert/ct_ev_whitelist.cc b/net/cert/ct_ev_whitelist.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..a7c2eb1fcd8a21eae71b83785702fa8be4d119bd |
--- /dev/null |
+++ b/net/cert/ct_ev_whitelist.cc |
@@ -0,0 +1,158 @@ |
+// Copyright 2014 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#include "net/cert/ct_ev_whitelist.h" |
+ |
+#include <set> |
+ |
+#include "base/big_endian.h" |
+#include "base/file_util.h" |
+#include "base/lazy_instance.h" |
+#include "base/logging.h" |
+ |
+namespace net { |
+ |
+namespace ct { |
+ |
+namespace { |
+base::LazyInstance<std::set<std::string> >::Leaky g_current_ev_whitelist = |
+ LAZY_INSTANCE_INITIALIZER; |
+ |
+const uint8 kCertHashLengthBits = 64; // 8 bytes |
+const uint64 kGolombMParameterBits = 47; // 2^47 |
+} // namespace |
+ |
+namespace internal { |
+ |
+BitStreamReader::BitStreamReader(const char* source, size_t length) |
+ : source_(source), length_(length), current_byte_(0), current_bit_(7) { |
+} |
+ |
+bool BitStreamReader::ReadUnaryEncoding(uint64* out) { |
+ uint64 res = 0; |
+ if (BitsLeft() == 0) |
+ return false; |
+ |
+ while ((BitsLeft() > 0) && ReadBit()) |
+ res++; |
+ |
+ *out = res; |
+ return true; |
+} |
+ |
+bool BitStreamReader::ReadBits(uint8 num_bits, uint64* out) { |
+ if (num_bits > 64) |
+ return false; |
+ |
+ if (BitsLeft() < num_bits) |
+ return false; |
+ |
+ uint64 res = 0; |
+ for (uint8 i = 0; i < num_bits; ++i) |
+ res |= (static_cast<uint64>(ReadBit()) << (num_bits - (i + 1))); |
+ |
+ *out = res; |
+ return true; |
+} |
+ |
+uint64 BitStreamReader::BitsLeft() const { |
+ if (current_byte_ == length_) |
+ return 0; |
+ return (length_ - (current_byte_ + 1)) * 8 + current_bit_ + 1; |
+} |
+ |
+uint8 BitStreamReader::ReadBit() { |
+ DCHECK_GT(BitsLeft(), 0u); |
+ DCHECK(current_bit_ < 8 && current_bit_ >= 0); |
+ uint8 res = (source_[current_byte_] & (1 << current_bit_)) >> current_bit_; |
+ current_bit_--; |
+ if (current_bit_ < 0) { |
+ current_byte_++; |
+ current_bit_ = 7; |
+ } |
+ |
+ return res; |
+} |
+ |
+bool UncompressEVWhitelist(const std::string& compressed_whitelist, |
+ std::set<std::string>* uncompressed_list) { |
+ BitStreamReader reader(compressed_whitelist.data(), |
+ compressed_whitelist.size()); |
+ std::set<std::string> result; |
+ |
+ VLOG(1) << "Uncompressing EV whitelist of size " |
+ << compressed_whitelist.size(); |
+ uint64 curr_hash(0); |
+ if (!reader.ReadBits(kCertHashLengthBits, &curr_hash)) { |
+ VLOG(1) << "Failed reading first hash."; |
+ return false; |
+ } |
+ char hash_bytes[8]; |
+ base::WriteBigEndian(hash_bytes, curr_hash); |
+ result.insert(std::string(hash_bytes, 8)); |
+ static const uint64 M = static_cast<uint64>(1) << kGolombMParameterBits; |
+ |
+ while (reader.BitsLeft() > kGolombMParameterBits) { |
+ uint64 read_prefix = 0; |
+ if (!reader.ReadUnaryEncoding(&read_prefix)) { |
+ VLOG(1) << "Failed reading unary-encoded prefix."; |
+ return false; |
+ } |
+ |
+ uint64 r = 0; |
+ if (!reader.ReadBits(kGolombMParameterBits, &r)) { |
+ VLOG(1) << "Failed reading " << kGolombMParameterBits << " bits."; |
+ return false; |
+ } |
+ |
+ uint64 curr_diff = read_prefix * M + r; |
+ curr_hash += curr_diff; |
+ |
+ base::WriteBigEndian(hash_bytes, curr_hash); |
+ result.insert(std::string(hash_bytes, 8)); |
+ } |
+ |
+ uncompressed_list->swap(result); |
+ return true; |
+} |
+ |
+void SetEVWhitelistData(std::set<std::string>& ev_whitelist) { |
+ g_current_ev_whitelist.Get().swap(ev_whitelist); |
+} |
+ |
+} // namespace internal |
+ |
+void SetEVWhitelistFromFile(const base::FilePath& compressed_whitelist_file) { |
+ VLOG(1) << "Setting EV whitelist from file: " |
+ << compressed_whitelist_file.value(); |
+ std::string compressed_list; |
+ if (!base::ReadFileToString(compressed_whitelist_file, &compressed_list)) { |
+ VLOG(1) << "Failed reading from " << compressed_whitelist_file.value(); |
+ return; |
+ } |
+ |
+ std::set<std::string> uncompressed_list; |
+ if (!internal::UncompressEVWhitelist(compressed_list, &uncompressed_list)) { |
+ VLOG(1) << "Failed uncompressing."; |
+ return; |
+ } |
+ VLOG(1) << "Uncompressing succeeded, hashes: " << uncompressed_list.size(); |
+ |
+ internal::SetEVWhitelistData(uncompressed_list); |
+} |
+ |
+bool IsCertificateHashInWhitelist(const std::string& certificate_hash) { |
+ const std::set<std::string>& current_ev_whitelist = |
+ g_current_ev_whitelist.Get(); |
+ return current_ev_whitelist.find(certificate_hash) != |
+ current_ev_whitelist.end(); |
+} |
+ |
+bool HasValidEVWhitelist() { |
+ return !g_current_ev_whitelist.Get().empty(); |
+} |
+ |
+} // namespace ct |
+ |
+} // namespace net |