X-Git-Url: https://git.openssl.org/?p=openssl.git;a=blobdiff_plain;f=crypto%2Frand%2Frand_unix.c;h=0ca66e41ffca60c237115c32fd0075725169ab89;hp=bf5c4c3499e6a4c4f3fb6b0dc18f47b4fe5e462f;hb=HEAD;hpb=cf0932cdd94f067ed18ce78bea038d919f69038f diff --git a/crypto/rand/rand_unix.c b/crypto/rand/rand_unix.c deleted file mode 100644 index bf5c4c3499..0000000000 --- a/crypto/rand/rand_unix.c +++ /dev/null @@ -1,704 +0,0 @@ -/* - * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved. - * - * Licensed under the Apache License 2.0 (the "License"). You may not use - * this file except in compliance with the License. You can obtain a copy - * in the file LICENSE in the source distribution or at - * https://www.openssl.org/source/license.html - */ - -#ifndef _GNU_SOURCE -# define _GNU_SOURCE -#endif -#include "e_os.h" -#include -#include "internal/cryptlib.h" -#include -#include "rand_lcl.h" -#include "internal/rand_int.h" -#include -#include "internal/dso.h" -#if defined(__linux) -# include -#endif -#if defined(__FreeBSD__) && !defined(OPENSSL_SYS_UEFI) -# include -# include -# include -#endif -#if defined(__OpenBSD__) || defined(__NetBSD__) -# include -#endif - -#if (defined(OPENSSL_SYS_UNIX) && !defined(OPENSSL_SYS_VXWORKS)) \ - || defined(__DJGPP__) -# include -# include -# include -# include -# include - -static uint64_t get_time_stamp(void); -static uint64_t get_timer_bits(void); - -/* Macro to convert two thirty two bit values into a sixty four bit one */ -# define TWO32TO64(a, b) ((((uint64_t)(a)) << 32) + (b)) - -/* - * Check for the existence and support of POSIX timers. The standard - * says that the _POSIX_TIMERS macro will have a positive value if they - * are available. - * - * However, we want an additional constraint: that the timer support does - * not require an extra library dependency. Early versions of glibc - * require -lrt to be specified on the link line to access the timers, - * so this needs to be checked for. - * - * It is worse because some libraries define __GLIBC__ but don't - * support the version testing macro (e.g. uClibc). This means - * an extra check is needed. - * - * The final condition is: - * "have posix timers and either not glibc or glibc without -lrt" - * - * The nested #if sequences are required to avoid using a parameterised - * macro that might be undefined. - */ -# undef OSSL_POSIX_TIMER_OKAY -# if defined(_POSIX_TIMERS) && _POSIX_TIMERS > 0 -# if defined(__GLIBC__) -# if defined(__GLIBC_PREREQ) -# if __GLIBC_PREREQ(2, 17) -# define OSSL_POSIX_TIMER_OKAY -# endif -# endif -# else -# define OSSL_POSIX_TIMER_OKAY -# endif -# endif -#endif /* defined(OPENSSL_SYS_UNIX) || defined(__DJGPP__) */ - -#if defined(OPENSSL_RAND_SEED_NONE) -/* none means none. this simplifies the following logic */ -# undef OPENSSL_RAND_SEED_OS -# undef OPENSSL_RAND_SEED_GETRANDOM -# undef OPENSSL_RAND_SEED_LIBRANDOM -# undef OPENSSL_RAND_SEED_DEVRANDOM -# undef OPENSSL_RAND_SEED_RDTSC -# undef OPENSSL_RAND_SEED_RDCPU -# undef OPENSSL_RAND_SEED_EGD -#endif - -#if defined(OPENSSL_SYS_UEFI) && !defined(OPENSSL_RAND_SEED_NONE) -# error "UEFI only supports seeding NONE" -#endif - -#if !(defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32) \ - || defined(OPENSSL_SYS_VMS) || defined(OPENSSL_SYS_VXWORKS) \ - || defined(OPENSSL_SYS_UEFI)) - -# if defined(OPENSSL_SYS_VOS) - -# ifndef OPENSSL_RAND_SEED_OS -# error "Unsupported seeding method configured; must be os" -# endif - -# if defined(OPENSSL_SYS_VOS_HPPA) && defined(OPENSSL_SYS_VOS_IA32) -# error "Unsupported HP-PA and IA32 at the same time." -# endif -# if !defined(OPENSSL_SYS_VOS_HPPA) && !defined(OPENSSL_SYS_VOS_IA32) -# error "Must have one of HP-PA or IA32" -# endif - -/* - * The following algorithm repeatedly samples the real-time clock (RTC) to - * generate a sequence of unpredictable data. The algorithm relies upon the - * uneven execution speed of the code (due to factors such as cache misses, - * interrupts, bus activity, and scheduling) and upon the rather large - * relative difference between the speed of the clock and the rate at which - * it can be read. If it is ported to an environment where execution speed - * is more constant or where the RTC ticks at a much slower rate, or the - * clock can be read with fewer instructions, it is likely that the results - * would be far more predictable. This should only be used for legacy - * platforms. - * - * As a precaution, we assume only 2 bits of entropy per byte. - */ -size_t rand_pool_acquire_entropy(RAND_POOL *pool) -{ - short int code; - int i, k; - size_t bytes_needed; - struct timespec ts; - unsigned char v; -# ifdef OPENSSL_SYS_VOS_HPPA - long duration; - extern void s$sleep(long *_duration, short int *_code); -# else - long long duration; - extern void s$sleep2(long long *_duration, short int *_code); -# endif - - bytes_needed = rand_pool_bytes_needed(pool, 4 /*entropy_factor*/); - - for (i = 0; i < bytes_needed; i++) { - /* - * burn some cpu; hope for interrupts, cache collisions, bus - * interference, etc. - */ - for (k = 0; k < 99; k++) - ts.tv_nsec = random(); - -# ifdef OPENSSL_SYS_VOS_HPPA - /* sleep for 1/1024 of a second (976 us). */ - duration = 1; - s$sleep(&duration, &code); -# else - /* sleep for 1/65536 of a second (15 us). */ - duration = 1; - s$sleep2(&duration, &code); -# endif - - /* Get wall clock time, take 8 bits. */ - clock_gettime(CLOCK_REALTIME, &ts); - v = (unsigned char)(ts.tv_nsec & 0xFF); - rand_pool_add(pool, arg, &v, sizeof(v) , 2); - } - return rand_pool_entropy_available(pool); -} - -void rand_pool_cleanup(void) -{ -} - -void rand_pool_keep_random_devices_open(int keep) -{ -} - -# else - -# if defined(OPENSSL_RAND_SEED_EGD) && \ - (defined(OPENSSL_NO_EGD) || !defined(DEVRANDOM_EGD)) -# error "Seeding uses EGD but EGD is turned off or no device given" -# endif - -# if defined(OPENSSL_RAND_SEED_DEVRANDOM) && !defined(DEVRANDOM) -# error "Seeding uses urandom but DEVRANDOM is not configured" -# endif - -# if defined(OPENSSL_RAND_SEED_OS) -# if !defined(DEVRANDOM) -# error "OS seeding requires DEVRANDOM to be configured" -# endif -# define OPENSSL_RAND_SEED_GETRANDOM -# define OPENSSL_RAND_SEED_DEVRANDOM -# endif - -# if defined(OPENSSL_RAND_SEED_LIBRANDOM) -# error "librandom not (yet) supported" -# endif - -# if (defined(__FreeBSD__) || defined(__NetBSD__)) && defined(KERN_ARND) -/* - * sysctl_random(): Use sysctl() to read a random number from the kernel - * Returns the number of bytes returned in buf on success, -1 on failure. - */ -static ssize_t sysctl_random(char *buf, size_t buflen) -{ - int mib[2]; - size_t done = 0; - size_t len; - - /* - * Note: sign conversion between size_t and ssize_t is safe even - * without a range check, see comment in syscall_random() - */ - - /* - * On FreeBSD old implementations returned longs, newer versions support - * variable sizes up to 256 byte. The code below would not work properly - * when the sysctl returns long and we want to request something not a - * multiple of longs, which should never be the case. - */ - if (!ossl_assert(buflen % sizeof(long) == 0)) { - errno = EINVAL; - return -1; - } - - /* - * On NetBSD before 4.0 KERN_ARND was an alias for KERN_URND, and only - * filled in an int, leaving the rest uninitialized. Since NetBSD 4.0 - * it returns a variable number of bytes with the current version supporting - * up to 256 bytes. - * Just return an error on older NetBSD versions. - */ -#if defined(__NetBSD__) && __NetBSD_Version__ < 400000000 - errno = ENOSYS; - return -1; -#endif - - mib[0] = CTL_KERN; - mib[1] = KERN_ARND; - - do { - len = buflen; - if (sysctl(mib, 2, buf, &len, NULL, 0) == -1) - return done > 0 ? done : -1; - done += len; - buf += len; - buflen -= len; - } while (buflen > 0); - - return done; -} -# endif - -# if defined(OPENSSL_RAND_SEED_GETRANDOM) - -# if defined(__linux) && !defined(__NR_getrandom) -# if defined(__arm__) && defined(__NR_SYSCALL_BASE) -# define __NR_getrandom (__NR_SYSCALL_BASE+384) -# elif defined(__i386__) -# define __NR_getrandom 355 -# elif defined(__x86_64__) && !defined(__ILP32__) -# define __NR_getrandom 318 -# endif -# endif - -/* - * syscall_random(): Try to get random data using a system call - * returns the number of bytes returned in buf, or < 0 on error. - */ -static ssize_t syscall_random(void *buf, size_t buflen) -{ - /* - * Note: 'buflen' equals the size of the buffer which is used by the - * get_entropy() callback of the RAND_DRBG. It is roughly bounded by - * - * 2 * RAND_POOL_FACTOR * (RAND_DRBG_STRENGTH / 8) = 2^14 - * - * which is way below the OSSL_SSIZE_MAX limit. Therefore sign conversion - * between size_t and ssize_t is safe even without a range check. - */ - - /* - * Do runtime detection to find getentropy(). - * - * Known OSs that should support this: - * - Darwin since 16 (OSX 10.12, IOS 10.0). - * - Solaris since 11.3 - * - OpenBSD since 5.6 - * - Linux since 3.17 with glibc 2.25 - * - FreeBSD since 12.0 (1200061) - */ -# if defined(__GNUC__) && __GNUC__>=2 && defined(__ELF__) && !defined(__hpux) - extern int getentropy(void *buffer, size_t length) __attribute__((weak)); - - if (getentropy != NULL) - return getentropy(buf, buflen) == 0 ? (ssize_t)buflen : -1; -# elif !defined(FIPS_MODE) - union { - void *p; - int (*f)(void *buffer, size_t length); - } p_getentropy; - - /* - * We could cache the result of the lookup, but we normally don't - * call this function often. - */ - ERR_set_mark(); - p_getentropy.p = DSO_global_lookup("getentropy"); - ERR_pop_to_mark(); - if (p_getentropy.p != NULL) - return p_getentropy.f(buf, buflen) == 0 ? (ssize_t)buflen : -1; -# endif - - /* Linux supports this since version 3.17 */ -# if defined(__linux) && defined(__NR_getrandom) - return syscall(__NR_getrandom, buf, buflen, 0); -# elif (defined(__FreeBSD__) || defined(__NetBSD__)) && defined(KERN_ARND) - return sysctl_random(buf, buflen); -# else - errno = ENOSYS; - return -1; -# endif -} -# endif /* defined(OPENSSL_RAND_SEED_GETRANDOM) */ - -# if defined(OPENSSL_RAND_SEED_DEVRANDOM) -static const char *random_device_paths[] = { DEVRANDOM }; -static struct random_device { - int fd; - dev_t dev; - ino_t ino; - mode_t mode; - dev_t rdev; -} random_devices[OSSL_NELEM(random_device_paths)]; -static int keep_random_devices_open = 1; - -/* - * Verify that the file descriptor associated with the random source is - * still valid. The rationale for doing this is the fact that it is not - * uncommon for daemons to close all open file handles when daemonizing. - * So the handle might have been closed or even reused for opening - * another file. - */ -static int check_random_device(struct random_device * rd) -{ - struct stat st; - - return rd->fd != -1 - && fstat(rd->fd, &st) != -1 - && rd->dev == st.st_dev - && rd->ino == st.st_ino - && ((rd->mode ^ st.st_mode) & ~(S_IRWXU | S_IRWXG | S_IRWXO)) == 0 - && rd->rdev == st.st_rdev; -} - -/* - * Open a random device if required and return its file descriptor or -1 on error - */ -static int get_random_device(size_t n) -{ - struct stat st; - struct random_device * rd = &random_devices[n]; - - /* reuse existing file descriptor if it is (still) valid */ - if (check_random_device(rd)) - return rd->fd; - - /* open the random device ... */ - if ((rd->fd = open(random_device_paths[n], O_RDONLY)) == -1) - return rd->fd; - - /* ... and cache its relevant stat(2) data */ - if (fstat(rd->fd, &st) != -1) { - rd->dev = st.st_dev; - rd->ino = st.st_ino; - rd->mode = st.st_mode; - rd->rdev = st.st_rdev; - } else { - close(rd->fd); - rd->fd = -1; - } - - return rd->fd; -} - -/* - * Close a random device making sure it is a random device - */ -static void close_random_device(size_t n) -{ - struct random_device * rd = &random_devices[n]; - - if (check_random_device(rd)) - close(rd->fd); - rd->fd = -1; -} - -int rand_pool_init(void) -{ - size_t i; - - for (i = 0; i < OSSL_NELEM(random_devices); i++) - random_devices[i].fd = -1; - - return 1; -} - -void rand_pool_cleanup(void) -{ - size_t i; - - for (i = 0; i < OSSL_NELEM(random_devices); i++) - close_random_device(i); -} - -void rand_pool_keep_random_devices_open(int keep) -{ - if (!keep) - rand_pool_cleanup(); - - keep_random_devices_open = keep; -} - -# else /* !defined(OPENSSL_RAND_SEED_DEVRANDOM) */ - -int rand_pool_init(void) -{ - return 1; -} - -void rand_pool_cleanup(void) -{ -} - -void rand_pool_keep_random_devices_open(int keep) -{ -} - -# endif /* defined(OPENSSL_RAND_SEED_DEVRANDOM) */ - -/* - * Try the various seeding methods in turn, exit when successful. - * - * TODO(DRBG): If more than one entropy source is available, is it - * preferable to stop as soon as enough entropy has been collected - * (as favored by @rsalz) or should one rather be defensive and add - * more entropy than requested and/or from different sources? - * - * Currently, the user can select multiple entropy sources in the - * configure step, yet in practice only the first available source - * will be used. A more flexible solution has been requested, but - * currently it is not clear how this can be achieved without - * overengineering the problem. There are many parameters which - * could be taken into account when selecting the order and amount - * of input from the different entropy sources (trust, quality, - * possibility of blocking). - */ -size_t rand_pool_acquire_entropy(RAND_POOL *pool) -{ -# if defined(OPENSSL_RAND_SEED_NONE) - return rand_pool_entropy_available(pool); -# else - size_t bytes_needed; - size_t entropy_available = 0; - unsigned char *buffer; - -# if defined(OPENSSL_RAND_SEED_GETRANDOM) - { - ssize_t bytes; - /* Maximum allowed number of consecutive unsuccessful attempts */ - int attempts = 3; - - bytes_needed = rand_pool_bytes_needed(pool, 1 /*entropy_factor*/); - while (bytes_needed != 0 && attempts-- > 0) { - buffer = rand_pool_add_begin(pool, bytes_needed); - bytes = syscall_random(buffer, bytes_needed); - if (bytes > 0) { - rand_pool_add_end(pool, bytes, 8 * bytes); - bytes_needed -= bytes; - attempts = 3; /* reset counter after successful attempt */ - } else if (bytes < 0 && errno != EINTR) { - break; - } - } - } - entropy_available = rand_pool_entropy_available(pool); - if (entropy_available > 0) - return entropy_available; -# endif - -# if defined(OPENSSL_RAND_SEED_LIBRANDOM) - { - /* Not yet implemented. */ - } -# endif - -# if defined(OPENSSL_RAND_SEED_DEVRANDOM) - bytes_needed = rand_pool_bytes_needed(pool, 1 /*entropy_factor*/); - { - size_t i; - - for (i = 0; bytes_needed > 0 && i < OSSL_NELEM(random_device_paths); i++) { - ssize_t bytes = 0; - /* Maximum allowed number of consecutive unsuccessful attempts */ - int attempts = 3; - const int fd = get_random_device(i); - - if (fd == -1) - continue; - - while (bytes_needed != 0 && attempts-- > 0) { - buffer = rand_pool_add_begin(pool, bytes_needed); - bytes = read(fd, buffer, bytes_needed); - - if (bytes > 0) { - rand_pool_add_end(pool, bytes, 8 * bytes); - bytes_needed -= bytes; - attempts = 3; /* reset counter after successful attempt */ - } else if (bytes < 0 && errno != EINTR) { - break; - } - } - if (bytes < 0 || !keep_random_devices_open) - close_random_device(i); - - bytes_needed = rand_pool_bytes_needed(pool, 1 /*entropy_factor*/); - } - entropy_available = rand_pool_entropy_available(pool); - if (entropy_available > 0) - return entropy_available; - } -# endif - -# if defined(OPENSSL_RAND_SEED_RDTSC) - entropy_available = rand_acquire_entropy_from_tsc(pool); - if (entropy_available > 0) - return entropy_available; -# endif - -# if defined(OPENSSL_RAND_SEED_RDCPU) - entropy_available = rand_acquire_entropy_from_cpu(pool); - if (entropy_available > 0) - return entropy_available; -# endif - -# if defined(OPENSSL_RAND_SEED_EGD) - bytes_needed = rand_pool_bytes_needed(pool, 1 /*entropy_factor*/); - if (bytes_needed > 0) { - static const char *paths[] = { DEVRANDOM_EGD, NULL }; - int i; - - for (i = 0; paths[i] != NULL; i++) { - buffer = rand_pool_add_begin(pool, bytes_needed); - if (buffer != NULL) { - size_t bytes = 0; - int num = RAND_query_egd_bytes(paths[i], - buffer, (int)bytes_needed); - if (num == (int)bytes_needed) - bytes = bytes_needed; - - rand_pool_add_end(pool, bytes, 8 * bytes); - entropy_available = rand_pool_entropy_available(pool); - } - if (entropy_available > 0) - return entropy_available; - } - } -# endif - - return rand_pool_entropy_available(pool); -# endif -} -# endif -#endif - -#if (defined(OPENSSL_SYS_UNIX) && !defined(OPENSSL_SYS_VXWORKS)) \ - || defined(__DJGPP__) -int rand_pool_add_nonce_data(RAND_POOL *pool) -{ - struct { - pid_t pid; - CRYPTO_THREAD_ID tid; - uint64_t time; - } data; - - /* Erase the entire structure including any padding */ - memset(&data, 0, sizeof(data)); - - /* - * Add process id, thread id, and a high resolution timestamp to - * ensure that the nonce is unique with high probability for - * different process instances. - */ - data.pid = getpid(); - data.tid = CRYPTO_THREAD_get_current_id(); - data.time = get_time_stamp(); - - return rand_pool_add(pool, (unsigned char *)&data, sizeof(data), 0); -} - -int rand_pool_add_additional_data(RAND_POOL *pool) -{ - struct { - CRYPTO_THREAD_ID tid; - uint64_t time; - } data; - - /* Erase the entire structure including any padding */ - memset(&data, 0, sizeof(data)); - - /* - * Add some noise from the thread id and a high resolution timer. - * The thread id adds a little randomness if the drbg is accessed - * concurrently (which is the case for the drbg). - */ - data.tid = CRYPTO_THREAD_get_current_id(); - data.time = get_timer_bits(); - - return rand_pool_add(pool, (unsigned char *)&data, sizeof(data), 0); -} - - -/* - * Get the current time with the highest possible resolution - * - * The time stamp is added to the nonce, so it is optimized for not repeating. - * The current time is ideal for this purpose, provided the computer's clock - * is synchronized. - */ -static uint64_t get_time_stamp(void) -{ -# if defined(OSSL_POSIX_TIMER_OKAY) - { - struct timespec ts; - - if (clock_gettime(CLOCK_REALTIME, &ts) == 0) - return TWO32TO64(ts.tv_sec, ts.tv_nsec); - } -# endif -# if defined(__unix__) \ - || (defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 200112L) - { - struct timeval tv; - - if (gettimeofday(&tv, NULL) == 0) - return TWO32TO64(tv.tv_sec, tv.tv_usec); - } -# endif - return time(NULL); -} - -/* - * Get an arbitrary timer value of the highest possible resolution - * - * The timer value is added as random noise to the additional data, - * which is not considered a trusted entropy sourec, so any result - * is acceptable. - */ -static uint64_t get_timer_bits(void) -{ - uint64_t res = OPENSSL_rdtsc(); - - if (res != 0) - return res; - -# if defined(__sun) || defined(__hpux) - return gethrtime(); -# elif defined(_AIX) - { - timebasestruct_t t; - - read_wall_time(&t, TIMEBASE_SZ); - return TWO32TO64(t.tb_high, t.tb_low); - } -# elif defined(OSSL_POSIX_TIMER_OKAY) - { - struct timespec ts; - -# ifdef CLOCK_BOOTTIME -# define CLOCK_TYPE CLOCK_BOOTTIME -# elif defined(_POSIX_MONOTONIC_CLOCK) -# define CLOCK_TYPE CLOCK_MONOTONIC -# else -# define CLOCK_TYPE CLOCK_REALTIME -# endif - - if (clock_gettime(CLOCK_TYPE, &ts) == 0) - return TWO32TO64(ts.tv_sec, ts.tv_nsec); - } -# endif -# if defined(__unix__) \ - || (defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 200112L) - { - struct timeval tv; - - if (gettimeofday(&tv, NULL) == 0) - return TWO32TO64(tv.tv_sec, tv.tv_usec); - } -# endif - return time(NULL); -} -#endif /* defined(OPENSSL_SYS_UNIX) || defined(__DJGPP__) */