/*
- * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* https://www.openssl.org/source/license.html
*/
-#include <stdio.h>
-
-#define USE_SOCKETS
#include "e_os.h"
+#include <stdio.h>
#include "internal/cryptlib.h"
#include <openssl/rand.h>
#include "rand_lcl.h"
-
-#if !(defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS) || defined(OPENSSL_SYS_VXWORKS) || defined(OPENSSL_SYS_UEFI))
-
+#include "internal/rand_int.h"
+#include <stdio.h>
+#ifdef OPENSSL_SYS_UNIX
# include <sys/types.h>
-# include <sys/time.h>
-# include <sys/times.h>
-# include <sys/stat.h>
-# include <fcntl.h>
# include <unistd.h>
-# include <time.h>
-# if defined(OPENSSL_SYS_LINUX) /* should actually be available virtually
- * everywhere */
-# include <poll.h>
-# endif
-# include <limits.h>
-# ifndef FD_SETSIZE
-# define FD_SETSIZE (8*sizeof(fd_set))
+# include <sys/time.h>
+
+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
+
+#if (defined(OPENSSL_SYS_VXWORKS) || defined(OPENSSL_SYS_UEFI)) && \
+ !defined(OPENSSL_RAND_SEED_NONE)
+# error "UEFI and VXWorks only support 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.
+ * 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.
*
- * If this code 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.
- *
- * As a precaution, we generate 4 times the minimum required amount of seed
- * data.
+ * As a precaution, we assume only 2 bits of entropy per byte.
*/
-
-int RAND_poll(void)
+size_t rand_pool_acquire_entropy(RAND_POOL *pool)
{
short int code;
- gid_t curr_gid;
- pid_t curr_pid;
- uid_t curr_uid;
int i, k;
+ size_t bytes_needed;
struct timespec ts;
unsigned char v;
-
# ifdef OPENSSL_SYS_VOS_HPPA
long duration;
extern void s$sleep(long *_duration, short int *_code);
# else
-# ifdef OPENSSL_SYS_VOS_IA32
long long duration;
extern void s$sleep2(long long *_duration, short int *_code);
-# else
-# error "Unsupported Platform."
-# endif /* OPENSSL_SYS_VOS_IA32 */
-# endif /* OPENSSL_SYS_VOS_HPPA */
-
- /*
- * Seed with the gid, pid, and uid, to ensure *some* variation between
- * different processes.
- */
-
- curr_gid = getgid();
- RAND_add(&curr_gid, sizeof curr_gid, 1);
- curr_gid = 0;
-
- curr_pid = getpid();
- RAND_add(&curr_pid, sizeof curr_pid, 1);
- curr_pid = 0;
+# endif
- curr_uid = getuid();
- RAND_add(&curr_uid, sizeof curr_uid, 1);
- curr_uid = 0;
+ bytes_needed = rand_pool_bytes_needed(pool, 2 /*entropy_per_byte*/);
- for (i = 0; i < (ENTROPY_NEEDED * 4); i++) {
+ for (i = 0; i < bytes_needed; i++) {
/*
* burn some cpu; hope for interrupts, cache collisions, bus
* interference, etc.
duration = 1;
s$sleep(&duration, &code);
# else
-# ifdef OPENSSL_SYS_VOS_IA32
/* sleep for 1/65536 of a second (15 us). */
duration = 1;
s$sleep2(&duration, &code);
-# endif /* OPENSSL_SYS_VOS_IA32 */
-# endif /* OPENSSL_SYS_VOS_HPPA */
+# endif
- /* get wall clock time. */
+ /* Get wall clock time, take 8 bits. */
clock_gettime(CLOCK_REALTIME, &ts);
-
- /* take 8 bits */
- v = (unsigned char)(ts.tv_nsec % 256);
- RAND_add(&v, sizeof v, 1);
- v = 0;
+ v = (unsigned char)(ts.tv_nsec & 0xFF);
+ rand_pool_add(pool, arg, &v, sizeof(v) , 2);
}
- return 1;
+ return rand_pool_entropy_available(pool);
}
-# elif defined __OpenBSD__
-int RAND_poll(void)
-{
- u_int32_t rnd = 0, i;
- unsigned char buf[ENTROPY_NEEDED];
-
- for (i = 0; i < sizeof(buf); i++) {
- if (i % 4 == 0)
- rnd = arc4random();
- buf[i] = rnd;
- rnd >>= 8;
- }
- RAND_add(buf, sizeof(buf), ENTROPY_NEEDED);
- OPENSSL_cleanse(buf, sizeof(buf));
- return 1;
-}
-# else /* !defined(__OpenBSD__) */
-int RAND_poll(void)
-{
- unsigned long l;
- pid_t curr_pid = getpid();
-# if defined(DEVRANDOM) || (!defined(OPENSS_NO_EGD) && defined(DEVRANDOM_EGD))
- unsigned char tmpbuf[ENTROPY_NEEDED];
- int n = 0;
+# 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
-# ifdef DEVRANDOM
- static const char *randomfiles[] = { DEVRANDOM };
- struct stat randomstats[OSSL_NELEM(randomfiles)];
- int fd;
- unsigned int i;
+
+# if defined(OPENSSL_RAND_SEED_DEVRANDOM) && !defined(DEVRANDOM)
+# error "Seeding uses urandom but DEVRANDOM is not configured"
# endif
-# if !defined(OPENSSL_NO_EGD) && defined(DEVRANDOM_EGD)
- static const char *egdsockets[] = { DEVRANDOM_EGD, NULL };
- const char **egdsocket = NULL;
+
+# if defined(OPENSSL_RAND_SEED_OS)
+# if !defined(DEVRANDOM)
+# error "OS seeding requires DEVRANDOM to be configured"
+# endif
+# define OPENSSL_RAND_SEED_DEVRANDOM
+# if defined(__GLIBC__) && defined(__GLIBC_PREREQ)
+# if __GLIBC_PREREQ(2, 25)
+# define OPENSSL_RAND_SEED_GETRANDOM
+# endif
+# endif
# endif
-# ifdef DEVRANDOM
- memset(randomstats, 0, sizeof(randomstats));
- /*
- * Use a random entropy pool device. Linux, FreeBSD and OpenBSD have
- * this. Use /dev/urandom if you can as /dev/random may block if it runs
- * out of random entries.
- */
+# ifdef OPENSSL_RAND_SEED_GETRANDOM
+# include <sys/random.h>
+# endif
- for (i = 0; (i < OSSL_NELEM(randomfiles)) && (n < ENTROPY_NEEDED); i++) {
- if ((fd = open(randomfiles[i], O_RDONLY
-# ifdef O_NONBLOCK
- | O_NONBLOCK
-# endif
-# ifdef O_BINARY
- | O_BINARY
+# if defined(OPENSSL_RAND_SEED_LIBRANDOM)
+# error "librandom not (yet) supported"
+# endif
+
+/*
+ * 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)
+{
+# ifdef OPENSSL_RAND_SEED_NONE
+ return rand_pool_entropy_available(pool);
+# else
+ size_t bytes_needed;
+ size_t entropy_available = 0;
+ unsigned char *buffer;
+
+# ifdef OPENSSL_RAND_SEED_GETRANDOM
+ bytes_needed = rand_pool_bytes_needed(pool, 8 /*entropy_per_byte*/);
+ buffer = rand_pool_add_begin(pool, bytes_needed);
+ if (buffer != NULL) {
+ size_t bytes = 0;
+
+ if (getrandom(buffer, bytes_needed, 0) == (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
-# ifdef O_NOCTTY /* If it happens to be a TTY (god forbid), do
- * not make it our controlling tty */
- | O_NOCTTY
+
+# if defined(OPENSSL_RAND_SEED_LIBRANDOM)
+ {
+ /* Not yet implemented. */
+ }
# endif
- )) >= 0) {
- int usec = 10 * 1000; /* spend 10ms on each file */
- int r;
- unsigned int j;
- struct stat *st = &randomstats[i];
-
- /*
- * Avoid using same input... Used to be O_NOFOLLOW above, but
- * it's not universally appropriate...
- */
- if (fstat(fd, st) != 0) {
- close(fd);
- continue;
- }
- for (j = 0; j < i; j++) {
- if (randomstats[j].st_ino == st->st_ino &&
- randomstats[j].st_dev == st->st_dev)
- break;
- }
- if (j < i) {
- close(fd);
+
+# ifdef OPENSSL_RAND_SEED_DEVRANDOM
+ bytes_needed = rand_pool_bytes_needed(pool, 8 /*entropy_per_byte*/);
+ if (bytes_needed > 0) {
+ static const char *paths[] = { DEVRANDOM, NULL };
+ FILE *fp;
+ int i;
+
+ for (i = 0; paths[i] != NULL; i++) {
+ if ((fp = fopen(paths[i], "rb")) == NULL)
continue;
+ setbuf(fp, NULL);
+ buffer = rand_pool_add_begin(pool, bytes_needed);
+ if (buffer != NULL) {
+ size_t bytes = 0;
+ if (fread(buffer, 1, bytes_needed, fp) == bytes_needed)
+ bytes = bytes_needed;
+
+ rand_pool_add_end(pool, bytes, 8 * bytes);
+ entropy_available = rand_pool_entropy_available(pool);
}
+ fclose(fp);
+ if (entropy_available > 0)
+ return entropy_available;
+
+ bytes_needed = rand_pool_bytes_needed(pool, 8 /*entropy_per_byte*/);
+ }
+ }
+# endif
- do {
- int try_read = 0;
-
-# if defined(OPENSSL_SYS_LINUX)
- /* use poll() */
- struct pollfd pset;
-
- pset.fd = fd;
- pset.events = POLLIN;
- pset.revents = 0;
-
- if (poll(&pset, 1, usec / 1000) < 0)
- usec = 0;
- else
- try_read = (pset.revents & POLLIN) != 0;
-
-# else
- /* use select() */
- fd_set fset;
- struct timeval t;
-
- t.tv_sec = 0;
- t.tv_usec = usec;
-
- if (FD_SETSIZE > 0 && (unsigned)fd >= FD_SETSIZE) {
- /*
- * can't use select, so just try to read once anyway
- */
- try_read = 1;
- } else {
- FD_ZERO(&fset);
- FD_SET(fd, &fset);
-
- if (select(fd + 1, &fset, NULL, NULL, &t) >= 0) {
- usec = t.tv_usec;
- if (FD_ISSET(fd, &fset))
- try_read = 1;
- } else
- usec = 0;
- }
+# ifdef OPENSSL_RAND_SEED_RDTSC
+ entropy_available = rand_acquire_entropy_from_tsc(pool);
+ if (entropy_available > 0)
+ return entropy_available;
# endif
- if (try_read) {
- r = read(fd, (unsigned char *)tmpbuf + n,
- ENTROPY_NEEDED - n);
- if (r > 0)
- n += r;
- } else
- r = -1;
-
- /*
- * Some Unixen will update t in select(), some won't. For
- * those who won't, or if we didn't use select() in the first
- * place, give up here, otherwise, we will do this once again
- * for the remaining time.
- */
- if (usec == 10 * 1000)
- usec = 0;
- }
- while ((r > 0 ||
- (errno == EINTR || errno == EAGAIN)) && usec != 0
- && n < ENTROPY_NEEDED);
+# ifdef OPENSSL_RAND_SEED_RDCPU
+ entropy_available = rand_acquire_entropy_from_cpu(pool);
+ if (entropy_available > 0)
+ return entropy_available;
+# endif
- close(fd);
+# ifdef OPENSSL_RAND_SEED_EGD
+ bytes_needed = rand_pool_bytes_needed(pool, 8 /*entropy_per_byte*/);
+ 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 /* defined(DEVRANDOM) */
+# endif
+
+ return rand_pool_entropy_available(pool);
+# endif
+}
+# endif
+#endif
+
+#ifdef OPENSSL_SYS_UNIX
+int rand_pool_add_nonce_data(RAND_POOL *pool)
+{
+ struct {
+ pid_t pid;
+ CRYPTO_THREAD_ID tid;
+ uint64_t time;
+ } data = { 0 };
-# if !defined(OPENSSL_NO_EGD) && defined(DEVRANDOM_EGD)
/*
- * Use an EGD socket to read entropy from an EGD or PRNGD entropy
- * collecting daemon.
+ * Add process id, thread id, and a high resolution timestamp to
+ * ensure that the nonce is unique whith high probability for
+ * different process instances.
*/
+ data.pid = getpid();
+ data.tid = CRYPTO_THREAD_get_current_id();
+ data.time = get_time_stamp();
- for (egdsocket = egdsockets; *egdsocket && n < ENTROPY_NEEDED;
- egdsocket++) {
- int r;
+ return rand_pool_add(pool, (unsigned char *)&data, sizeof(data), 0);
+}
- r = RAND_query_egd_bytes(*egdsocket, (unsigned char *)tmpbuf + n,
- ENTROPY_NEEDED - n);
- if (r > 0)
- n += r;
+int rand_pool_add_additional_data(RAND_POOL *pool)
+{
+ struct {
+ CRYPTO_THREAD_ID tid;
+ uint64_t time;
+ } data = { 0 };
+
+ /*
+ * 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 <master> 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 /* defined(DEVRANDOM_EGD) */
+# endif
+# if defined(__unix__) \
+ || (defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 200112L)
+ {
+ struct timeval tv;
-# if defined(DEVRANDOM) || (!defined(OPENSSL_NO_EGD) && defined(DEVRANDOM_EGD))
- if (n > 0) {
- RAND_add(tmpbuf, sizeof tmpbuf, (double)n);
- OPENSSL_cleanse(tmpbuf, n);
+ if (gettimeofday(&tv, NULL) == 0)
+ return TWO32TO64(tv.tv_sec, tv.tv_usec);
}
-# endif
+# 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();
- /* put in some default random data, we need more than just this */
- l = curr_pid;
- RAND_add(&l, sizeof(l), 0.0);
- l = getuid();
- RAND_add(&l, sizeof(l), 0.0);
+ if (res != 0)
+ return res;
- l = time(NULL);
- RAND_add(&l, sizeof(l), 0.0);
+# if defined(__sun) || defined(__hpux)
+ return gethrtime();
+# elif defined(_AIX)
+ {
+ timebasestruct_t t;
-# if defined(DEVRANDOM) || (!defined(OPENSSL_NO_EGD) && defined(DEVRANDOM_EGD))
- return 1;
+ 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
- return 0;
+# define CLOCK_TYPE CLOCK_REALTIME
# endif
-}
-# endif /* defined(__OpenBSD__) */
-#endif /* !(defined(OPENSSL_SYS_WINDOWS) ||
- * defined(OPENSSL_SYS_WIN32) ||
- * defined(OPENSSL_SYS_VMS) ||
- * defined(OPENSSL_SYS_VXWORKS) */
+ 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 defined(OPENSSL_SYS_VXWORKS) || defined(OPENSSL_SYS_UEFI)
-int RAND_poll(void)
-{
- return 0;
+ if (gettimeofday(&tv, NULL) == 0)
+ return TWO32TO64(tv.tv_sec, tv.tv_usec);
+ }
+# endif
+ return time(NULL);
}
#endif
projects / openssl.git / blobdiff