| /* |
| * libjingle |
| * Copyright 2004--2005, Google Inc. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright notice, |
| * this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright notice, |
| * this list of conditions and the following disclaimer in the documentation |
| * and/or other materials provided with the distribution. |
| * 3. The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO |
| * EVENT SHALL THE AUTHOR 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. |
| */ |
| |
| #include "talk/base/helpers.h" |
| #include "talk/base/time.h" |
| #include <cstdlib> |
| #include <cassert> |
| |
| // TODO: Change this implementation to use OpenSSL's RAND_bytes. That will |
| // give cryptographically random values on all platforms. |
| |
| #ifdef WIN32 |
| #include <time.h> |
| #include <windows.h> |
| #endif |
| |
| namespace cricket { |
| |
| static long g_seed = 1L; |
| |
| int GetRandom() { |
| return ((g_seed = g_seed * 214013L + 2531011L) >> 16) & 0x7fff; |
| } |
| |
| static bool s_initrandom; |
| |
| long GetRandomSeed() { |
| return g_seed; |
| } |
| |
| void SetRandomSeed(unsigned long seed) |
| { |
| s_initrandom = true; |
| g_seed = (long)seed; |
| } |
| |
| void InitRandom(const char *client_unique, size_t len) { |
| // Hash this string - unique per client |
| |
| uint32 hash = 0; |
| if (client_unique != NULL) { |
| for (int i = 0; i < (int)len; i++) |
| hash = ((hash << 2) + hash) + client_unique[i]; |
| } |
| |
| // Now initialize the seed against a high resolution |
| // counter |
| |
| unsigned long seed = GetRandomSeed(); |
| |
| #ifdef WIN32 |
| bool success = false; |
| HCRYPTPROV hProv = NULL; |
| if (CryptAcquireContext(&hProv, NULL, NULL, PROV_RSA_FULL, |
| CRYPT_VERIFYCONTEXT | CRYPT_SILENT)) { |
| success = (FALSE != CryptGenRandom(hProv, |
| sizeof(seed), |
| reinterpret_cast<BYTE*>(&seed))); |
| CryptReleaseContext(hProv, 0); |
| } |
| |
| if (!success) { |
| LARGE_INTEGER big; |
| QueryPerformanceCounter(&big); |
| seed = big.LowPart; |
| } |
| #else |
| seed = talk_base::Time(); |
| #endif |
| |
| SetRandomSeed(seed ^ hash); |
| } |
| |
| const char BASE64[64] = { |
| 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', |
| 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', |
| 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', |
| 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', |
| '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/' |
| }; |
| |
| // Generates a random string of the given length. We generate base64 values so |
| // that they will be printable, though that's not necessary. |
| |
| std::string CreateRandomString(int len) { |
| // Random number generator should of been initialized! |
| assert(s_initrandom); |
| if (!s_initrandom) |
| InitRandom(0, 0); |
| |
| std::string str; |
| for (int i = 0; i < len; i++) |
| #if defined(_MSC_VER) && _MSC_VER < 1300 |
| str.insert(str.end(), BASE64[GetRandom() & 63]); |
| #else |
| str.push_back(BASE64[GetRandom() & 63]); |
| #endif |
| return str; |
| } |
| |
| uint32 CreateRandomId() { |
| uint8 b1 = (uint8)(GetRandom() & 255); |
| uint8 b2 = (uint8)(GetRandom() & 255); |
| uint8 b3 = (uint8)(GetRandom() & 255); |
| uint8 b4 = (uint8)(GetRandom() & 255); |
| return b1 | (b2 << 8) | (b3 << 16) | (b4 << 24); |
| } |
| |
| bool IsBase64Char(char ch) { |
| return (('A' <= ch) && (ch <= 'Z')) || |
| (('a' <= ch) && (ch <= 'z')) || |
| (('0' <= ch) && (ch <= '9')) || |
| (ch == '+') || (ch == '/'); |
| } |
| |
| bool IsBase64Encoded(const std::string& str) { |
| for (size_t i = 0; i < str.size(); ++i) { |
| if (!IsBase64Char(str.at(i))) |
| return false; |
| } |
| return true; |
| } |
| |
| } // namespace cricket |