| // Copyright 2012 The Chromium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "rlz/lib/machine_id.h" |
| |
| #include <stddef.h> |
| |
| #include "base/hash/sha1.h" |
| #include "base/rand_util.h" |
| #include "base/ranges/algorithm.h" |
| #include "base/strings/stringprintf.h" |
| #include "build/chromeos_buildflags.h" |
| #include "rlz/lib/assert.h" |
| #include "rlz/lib/crc8.h" |
| #include "rlz/lib/string_utils.h" |
| |
| namespace rlz_lib { |
| |
| bool GetMachineId(std::string* machine_id) { |
| if (!machine_id) |
| return false; |
| |
| #if BUILDFLAG(IS_CHROMEOS_ASH) |
| |
| // Generate a random machine Id each time this function is called. This |
| // prevents the RLZ server from correlating two RLZ pings from the same |
| // Chrome OS device. |
| // |
| // The Id should be 50 characters long and begin with "nonce-". Generate 23 |
| // cryptographically random bytes, then convert to a printable string using |
| // 2 hex digits per byte for a string of length 46 characters. Truncate last |
| // hex character for 45 characters. |
| unsigned char bytes[23]; |
| std::string str_bytes; |
| base::RandBytes(bytes); |
| rlz_lib::BytesToString(bytes, sizeof(bytes), &str_bytes); |
| str_bytes.resize(45); |
| machine_id->clear(); |
| base::StringAppendF(machine_id, "NONCE%s", str_bytes.c_str()); |
| DCHECK_EQ(50u, machine_id->length()); |
| return true; |
| |
| #else |
| |
| static std::string calculated_id; |
| static bool calculated = false; |
| if (calculated) { |
| *machine_id = calculated_id; |
| return true; |
| } |
| |
| std::u16string sid_string; |
| int volume_id; |
| if (!GetRawMachineId(&sid_string, &volume_id)) |
| return false; |
| |
| if (!testing::GetMachineIdImpl(sid_string, volume_id, machine_id)) |
| return false; |
| |
| calculated = true; |
| calculated_id = *machine_id; |
| return true; |
| |
| #endif // BUILDFLAG(IS_CHROMEOS_ASH) |
| } |
| |
| namespace testing { |
| |
| bool GetMachineIdImpl(const std::u16string& sid_string, |
| 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); |
| std::vector<unsigned char> id_binary(kSizeWithoutChecksum + 1, 0); |
| |
| if (!sid_string.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(std::u16string::value_type); |
| const char* buffer = reinterpret_cast<const char*>(sid_string.c_str()); |
| std::string sid_string_buffer(buffer, byte_count); |
| |
| // Note that digest can have embedded nulls. |
| std::string digest(base::SHA1HashString(sid_string_buffer)); |
| VERIFY(digest.size() == base::kSHA1Length); |
| base::ranges::copy(digest, 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>( |
| (volume_id >> shift_bits) & 0xFF); |
| } |
| |
| // Append the checksum byte. |
| if (!sid_string.empty() || (0 != volume_id)) |
| rlz_lib::Crc8::Generate(id_binary.data(), kSizeWithoutChecksum, |
| &id_binary[kSizeWithoutChecksum]); |
| |
| return rlz_lib::BytesToString(id_binary.data(), kSizeWithoutChecksum + 1, |
| machine_id); |
| } |
| |
| } // namespace testing |
| |
| } // namespace rlz_lib |