The Tor Browser / file comparison
comparison: media/webrtc/signaling/src/sipcc/plat/unix-common/random.c
media/webrtc/signaling/src/sipcc/plat/unix-common/random.c
- branch
- TOR_BUG_9701
- changeset 10
- ac0c01689b40
equal
deleted
inserted
replaced
| -1:000000000000 | 0:f5eb73a76077 |
|---|---|
| 1 /* This Source Code Form is subject to the terms of the Mozilla Public | |
| 2 * License, v. 2.0. If a copy of the MPL was not distributed with this | |
| 3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ | |
| 4 | |
| 5 #include <sys/types.h> | |
| 6 #include <unistd.h> | |
| 7 #include <fcntl.h> | |
| 8 #include <syslog.h> | |
| 9 #include <inttypes.h> | |
| 10 | |
| 11 /** | |
| 12 * platGenerateCryptoRand | |
| 13 * @brief Generates a Random Number | |
| 14 * | |
| 15 * Generate crypto graphically random number for a desired length. | |
| 16 * The function uses "secd" 's provided API. The random bytes are | |
| 17 * generated by "secd" which runs as another process. The function | |
| 18 * will be much slower than the cpr_rand(). This function should be | |
| 19 * used when good random number is needed such as random number that | |
| 20 * to be used for SRTP key for an example. | |
| 21 * | |
| 22 * @param[in] buf - pointer to the buffer to store the result of random | |
| 23 * bytes requested. | |
| 24 * @param[in] len - pointer to the length of the desired random bytes. | |
| 25 * When calling the function, the integer's value | |
| 26 * should be set to the desired number of random | |
| 27 * bytes ('buf' should be of at least this size). | |
| 28 * upon success, its value will be set to the | |
| 29 * actual number of random bytes being returned. | |
| 30 * (realistically, there is a maximum number of | |
| 31 * random bytes that can be returned at a time. | |
| 32 * if the caller request more than that, the | |
| 33 * 'len' will indicate how many bytes are actually being | |
| 34 * returned) on failure, its value will be set to 0. | |
| 35 * | |
| 36 * @return | |
| 37 * 1 - success. | |
| 38 * 0 - fail. | |
| 39 * | |
| 40 * @note This function MUST BE REWRITTEN BY THE VENDORS | |
| 41 * @note The intent of this function is to generate a cryptographically strong | |
| 42 * random number. Vendors can map this to HandyIron or OpenSSL random number | |
| 43 * generation functions. | |
| 44 */ | |
| 45 int | |
| 46 platGenerateCryptoRand(uint8_t *buf, int *len) | |
| 47 { | |
| 48 int fd; | |
| 49 int rc = 0; | |
| 50 ssize_t s; | |
| 51 | |
| 52 if ((fd = open("/dev/urandom", O_RDONLY)) == -1) { | |
| 53 syslog(LOG_ERR, "Failed to open prng driver"); | |
| 54 return 0; | |
| 55 } | |
| 56 | |
| 57 /* | |
| 58 * Try to read the given amount of bytes from the PRNG device. We do not | |
| 59 * handle short reads but just return the number of bytes read from the | |
| 60 * device. The caller has to manage this. | |
| 61 * E.g. gsmsdp_generate_key() in core/gsm/gsm_sdp_crypto.c | |
| 62 */ | |
| 63 s = read(fd, buf, (size_t) *len); | |
| 64 | |
| 65 if (s > 0) { | |
| 66 *len = s; | |
| 67 rc = 1; /* Success */ | |
| 68 } else { | |
| 69 *len = 0; | |
| 70 rc = 0; /* Failure */ | |
| 71 } | |
| 72 | |
| 73 (void) close(fd); | |
| 74 return rc; | |
| 75 } | |
| 76 |
