summaryrefslogtreecommitdiff
path: root/src/common
diff options
context:
space:
mode:
Diffstat (limited to 'src/common')
-rw-r--r--src/common/address_set.c2
-rw-r--r--src/common/aes.c5
-rw-r--r--src/common/compat_libevent.c49
-rw-r--r--src/common/compat_libevent.h3
-rw-r--r--src/common/compat_time.c54
-rw-r--r--src/common/compat_time.h29
-rw-r--r--src/common/crypto.c630
-rw-r--r--src/common/crypto.h40
-rw-r--r--src/common/crypto_curve25519.c5
-rw-r--r--src/common/crypto_digest.c9
-rw-r--r--src/common/crypto_ed25519.c6
-rw-r--r--src/common/crypto_format.c4
-rw-r--r--src/common/crypto_pwbox.c6
-rw-r--r--src/common/crypto_rand.c615
-rw-r--r--src/common/crypto_rand.h52
-rw-r--r--src/common/crypto_rsa.c8
-rw-r--r--src/common/crypto_rsa.h2
-rw-r--r--src/common/crypto_s2k.c8
-rw-r--r--src/common/crypto_util.c107
-rw-r--r--src/common/crypto_util.h27
-rw-r--r--src/common/include.am10
-rw-r--r--src/common/log.c25
-rw-r--r--src/common/sandbox.c3
-rw-r--r--src/common/token_bucket.c13
-rw-r--r--src/common/token_bucket.h4
-rw-r--r--src/common/torint.h2
-rw-r--r--src/common/torlog.h2
-rw-r--r--src/common/tortls.c21
-rw-r--r--src/common/util.c22
-rw-r--r--src/common/util.h3
-rw-r--r--src/common/workqueue.c2
31 files changed, 1034 insertions, 734 deletions
diff --git a/src/common/address_set.c b/src/common/address_set.c
index f61fa294e0..b2f4bb4c95 100644
--- a/src/common/address_set.c
+++ b/src/common/address_set.c
@@ -15,7 +15,7 @@
#include "address.h"
#include "compat.h"
#include "container.h"
-#include "crypto.h"
+#include "crypto_rand.h"
#include "util.h"
#include "siphash.h"
diff --git a/src/common/aes.c b/src/common/aes.c
index 5d0841dfa3..a83a654348 100644
--- a/src/common/aes.c
+++ b/src/common/aes.c
@@ -17,7 +17,6 @@
#endif
#include <openssl/opensslv.h>
-#include "crypto.h"
#include "crypto_openssl_mgt.h"
#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(1,0,0)
@@ -116,7 +115,11 @@ aes_cipher_free_(aes_cnt_cipher_t *cipher_)
if (!cipher_)
return;
EVP_CIPHER_CTX *cipher = (EVP_CIPHER_CTX *) cipher_;
+#if OPENSSL_VERSION_NUMBER >= OPENSSL_V_SERIES(1,1,0)
+ EVP_CIPHER_CTX_reset(cipher);
+#else
EVP_CIPHER_CTX_cleanup(cipher);
+#endif
EVP_CIPHER_CTX_free(cipher);
}
void
diff --git a/src/common/compat_libevent.c b/src/common/compat_libevent.c
index 9936c0aac4..fa00fb836b 100644
--- a/src/common/compat_libevent.c
+++ b/src/common/compat_libevent.c
@@ -11,7 +11,7 @@
#define COMPAT_LIBEVENT_PRIVATE
#include "compat_libevent.h"
-#include "crypto.h"
+#include "crypto_rand.h"
#include "util.h"
#include "torlog.h"
@@ -494,51 +494,7 @@ tor_libevent_exit_loop_after_callback(struct event_base *base)
event_base_loopbreak(base);
}
-#if defined(LIBEVENT_VERSION_NUMBER) && \
- LIBEVENT_VERSION_NUMBER >= V(2,1,1) && \
- !defined(TOR_UNIT_TESTS)
-void
-tor_gettimeofday_cached(struct timeval *tv)
-{
- event_base_gettimeofday_cached(the_event_base, tv);
-}
-void
-tor_gettimeofday_cache_clear(void)
-{
- event_base_update_cache_time(the_event_base);
-}
-#else /* !(defined(LIBEVENT_VERSION_NUMBER) && ...) */
-/** Cache the current hi-res time; the cache gets reset when libevent
- * calls us. */
-static struct timeval cached_time_hires = {0, 0};
-
-/** Return a fairly recent view of the current time. */
-void
-tor_gettimeofday_cached(struct timeval *tv)
-{
- if (cached_time_hires.tv_sec == 0) {
- tor_gettimeofday(&cached_time_hires);
- }
- *tv = cached_time_hires;
-}
-
-/** Reset the cached view of the current time, so that the next time we try
- * to learn it, we will get an up-to-date value. */
-void
-tor_gettimeofday_cache_clear(void)
-{
- cached_time_hires.tv_sec = 0;
-}
-
-#ifdef TOR_UNIT_TESTS
-/** For testing: force-update the cached time to a given value. */
-void
-tor_gettimeofday_cache_set(const struct timeval *tv)
-{
- tor_assert(tv);
- memcpy(&cached_time_hires, tv, sizeof(*tv));
-}
-
+#if defined(TOR_UNIT_TESTS)
/** For testing: called post-fork to make libevent reinitialize
* kernel structures. */
void
@@ -548,5 +504,4 @@ tor_libevent_postfork(void)
tor_assert(r == 0);
}
#endif /* defined(TOR_UNIT_TESTS) */
-#endif /* defined(LIBEVENT_VERSION_NUMBER) && ... */
diff --git a/src/common/compat_libevent.h b/src/common/compat_libevent.h
index 29c6ad375a..e2747860a9 100644
--- a/src/common/compat_libevent.h
+++ b/src/common/compat_libevent.h
@@ -68,10 +68,7 @@ void tor_libevent_free_all(void);
int tor_init_libevent_rng(void);
-void tor_gettimeofday_cached(struct timeval *tv);
-void tor_gettimeofday_cache_clear(void);
#ifdef TOR_UNIT_TESTS
-void tor_gettimeofday_cache_set(const struct timeval *tv);
void tor_libevent_postfork(void);
#endif
diff --git a/src/common/compat_time.c b/src/common/compat_time.c
index b940447b67..40847a8442 100644
--- a/src/common/compat_time.c
+++ b/src/common/compat_time.c
@@ -71,8 +71,8 @@ tor_sleep_msec(int msec)
/** Set *timeval to the current time of day. On error, log and terminate.
* (Same as gettimeofday(timeval,NULL), but never returns -1.)
*/
-void
-tor_gettimeofday(struct timeval *timeval)
+MOCK_IMPL(void,
+tor_gettimeofday, (struct timeval *timeval))
{
#ifdef _WIN32
/* Epoch bias copied from perl: number of units between windows epoch and
@@ -279,6 +279,7 @@ monotime_reset_ratchets_for_testing(void)
* nanoseconds.
*/
static struct mach_timebase_info mach_time_info;
+static struct mach_timebase_info mach_time_info_msec_cvt;
static int monotime_shift = 0;
static void
@@ -296,6 +297,14 @@ monotime_init_internal(void)
// requires that tor_log2(0) == 0.
monotime_shift = tor_log2(ms_per_tick);
}
+ {
+ // For converting ticks to milliseconds in a 32-bit-friendly way, we
+ // will first right-shift by 20, and then multiply by 20/19, since
+ // (1<<20) * 19/20 is about 1e6. We precompute a new numerate and
+ // denominator here to avoid multiple multiplies.
+ mach_time_info_msec_cvt.numer = mach_time_info.numer * 20;
+ mach_time_info_msec_cvt.denom = mach_time_info.denom * 19;
+ }
}
/**
@@ -345,6 +354,22 @@ monotime_diff_nsec(const monotime_t *start,
return diff_nsec;
}
+int32_t
+monotime_coarse_diff_msec32_(const monotime_coarse_t *start,
+ const monotime_coarse_t *end)
+{
+ if (BUG(mach_time_info.denom == 0)) {
+ monotime_init();
+ }
+ const int64_t diff_ticks = end->abstime_ - start->abstime_;
+
+ /* We already require in di_ops.c that right-shift performs a sign-extend. */
+ const int32_t diff_microticks = (int32_t)(diff_ticks >> 20);
+
+ return (diff_microticks * mach_time_info_msec_cvt.numer) /
+ mach_time_info_msec_cvt.denom;
+}
+
uint32_t
monotime_coarse_to_stamp(const monotime_coarse_t *t)
{
@@ -443,6 +468,15 @@ monotime_diff_nsec(const monotime_t *start,
return diff_nsec;
}
+int32_t
+monotime_coarse_diff_msec32_(const monotime_coarse_t *start,
+ const monotime_coarse_t *end)
+{
+ const int32_t diff_sec = (int32_t)(end->ts_.tv_sec - start->ts_.tv_sec);
+ const int32_t diff_nsec = (int32_t)(end->ts_.tv_nsec - start->ts_.tv_nsec);
+ return diff_sec * 1000 + diff_nsec / ONE_MILLION;
+}
+
/* This value is ONE_BILLION >> 20. */
static const uint32_t STAMP_TICKS_PER_SECOND = 953;
@@ -592,6 +626,13 @@ monotime_coarse_diff_msec(const monotime_coarse_t *start,
return diff_ticks;
}
+int32_t
+monotime_coarse_diff_msec32_(const monotime_coarse_t *start,
+ const monotime_coarse_t *end)
+{
+ return (int32_t)monotime_coarse_diff_msec(start, end);
+}
+
int64_t
monotime_coarse_diff_usec(const monotime_coarse_t *start,
const monotime_coarse_t *end)
@@ -677,6 +718,15 @@ monotime_diff_nsec(const monotime_t *start,
return (diff.tv_sec * ONE_BILLION + diff.tv_usec * 1000);
}
+int32_t
+monotime_coarse_diff_msec32_(const monotime_coarse_t *start,
+ const monotime_coarse_t *end)
+{
+ struct timeval diff;
+ timersub(&end->tv_, &start->tv_, &diff);
+ return diff.tv_sec * 1000 + diff.tv_usec / 1000;
+}
+
/* This value is ONE_MILLION >> 10. */
static const uint32_t STAMP_TICKS_PER_SECOND = 976;
diff --git a/src/common/compat_time.h b/src/common/compat_time.h
index 75b57f6f24..57ab20ab11 100644
--- a/src/common/compat_time.h
+++ b/src/common/compat_time.h
@@ -173,7 +173,34 @@ void monotime_coarse_add_msec(monotime_coarse_t *out,
#define monotime_coarse_add_msec monotime_add_msec
#endif /* defined(MONOTIME_COARSE_TYPE_IS_DIFFERENT) */
-void tor_gettimeofday(struct timeval *timeval);
+/**
+ * As monotime_coarse_diff_msec, but avoid 64-bit division.
+ *
+ * Requires that the difference fit into an int32_t; not for use with
+ * large time differences.
+ */
+int32_t monotime_coarse_diff_msec32_(const monotime_coarse_t *start,
+ const monotime_coarse_t *end);
+
+/**
+ * As monotime_coarse_diff_msec, but avoid 64-bit division if it is expensive.
+ *
+ * Requires that the difference fit into an int32_t; not for use with
+ * large time differences.
+ */
+static inline int32_t
+monotime_coarse_diff_msec32(const monotime_coarse_t *start,
+ const monotime_coarse_t *end)
+{
+#if SIZEOF_VOID_P == 8
+ // on a 64-bit platform, let's assume 64/64 division is cheap.
+ return (int32_t) monotime_coarse_diff_msec(start, end);
+#else
+ return monotime_coarse_diff_msec32_(start, end);
+#endif
+}
+
+MOCK_DECL(void, tor_gettimeofday, (struct timeval *timeval));
#ifdef TOR_UNIT_TESTS
void tor_sleep_msec(int msec);
diff --git a/src/common/crypto.c b/src/common/crypto.c
index 9fcd17742c..052f31723b 100644
--- a/src/common/crypto.c
+++ b/src/common/crypto.c
@@ -23,26 +23,26 @@
#endif /* defined(_WIN32) */
#define CRYPTO_PRIVATE
-#include "crypto.h"
#include "compat_openssl.h"
+#include "crypto.h"
#include "crypto_curve25519.h"
+#include "crypto_digest.h"
#include "crypto_ed25519.h"
#include "crypto_format.h"
+#include "crypto_rand.h"
#include "crypto_rsa.h"
-#include "crypto_digest.h"
+#include "crypto_util.h"
DISABLE_GCC_WARNING(redundant-decls)
#include <openssl/err.h>
-#include <openssl/rsa.h>
-#include <openssl/pem.h>
#include <openssl/evp.h>
#include <openssl/engine.h>
-#include <openssl/rand.h>
#include <openssl/bn.h>
#include <openssl/dh.h>
#include <openssl/conf.h>
#include <openssl/hmac.h>
+#include <openssl/ssl.h>
ENABLE_GCC_WARNING(redundant-decls)
@@ -60,18 +60,6 @@ ENABLE_GCC_WARNING(redundant-decls)
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
-#ifdef HAVE_FCNTL_H
-#include <fcntl.h>
-#endif
-#ifdef HAVE_SYS_FCNTL_H
-#include <sys/fcntl.h>
-#endif
-#ifdef HAVE_SYS_SYSCALL_H
-#include <sys/syscall.h>
-#endif
-#ifdef HAVE_SYS_RANDOM_H
-#include <sys/random.h>
-#endif
#include "torlog.h"
#include "torint.h"
@@ -84,12 +72,6 @@ ENABLE_GCC_WARNING(redundant-decls)
#include "keccak-tiny/keccak-tiny.h"
-/** Longest recognized */
-#define MAX_DNS_LABEL_SIZE 63
-
-/** Largest strong entropy request */
-#define MAX_STRONGEST_RAND_SIZE 256
-
/** A structure to hold the first half (x, g^x) of a Diffie-Hellman handshake
* while we're waiting for the second.*/
struct crypto_dh_t {
@@ -162,23 +144,6 @@ try_load_engine(const char *path, const char *engine)
}
#endif /* !defined(DISABLE_ENGINES) */
-/** Make sure that openssl is using its default PRNG. Return 1 if we had to
- * adjust it; 0 otherwise. */
-STATIC int
-crypto_force_rand_ssleay(void)
-{
- RAND_METHOD *default_method;
- default_method = RAND_OpenSSL();
- if (RAND_get_rand_method() != default_method) {
- log_notice(LD_CRYPTO, "It appears that one of our engines has provided "
- "a replacement the OpenSSL RNG. Resetting it to the default "
- "implementation.");
- RAND_set_rand_method(default_method);
- return 1;
- }
- return 0;
-}
-
static int have_seeded_siphash = 0;
/** Set up the siphash key if we haven't already done so. */
@@ -204,8 +169,15 @@ crypto_early_init(void)
crypto_early_initialized_ = 1;
+#if OPENSSL_VERSION_NUMBER >= OPENSSL_V_SERIES(1,1,0)
+ OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS |
+ OPENSSL_INIT_LOAD_CRYPTO_STRINGS |
+ OPENSSL_INIT_ADD_ALL_CIPHERS |
+ OPENSSL_INIT_ADD_ALL_DIGESTS, NULL);
+#else
ERR_load_crypto_strings();
OpenSSL_add_all_algorithms();
+#endif
setup_openssl_threading();
@@ -1083,576 +1055,6 @@ crypto_dh_free_(crypto_dh_t *dh)
tor_free(dh);
}
-/* random numbers */
-
-/** How many bytes of entropy we add at once.
- *
- * This is how much entropy OpenSSL likes to add right now, so maybe it will
- * work for us too. */
-#define ADD_ENTROPY 32
-
-/** Set the seed of the weak RNG to a random value. */
-void
-crypto_seed_weak_rng(tor_weak_rng_t *rng)
-{
- unsigned seed;
- crypto_rand((void*)&seed, sizeof(seed));
- tor_init_weak_random(rng, seed);
-}
-
-#ifdef TOR_UNIT_TESTS
-int break_strongest_rng_syscall = 0;
-int break_strongest_rng_fallback = 0;
-#endif
-
-/** Try to get <b>out_len</b> bytes of the strongest entropy we can generate,
- * via system calls, storing it into <b>out</b>. Return 0 on success, -1 on
- * failure. A maximum request size of 256 bytes is imposed.
- */
-static int
-crypto_strongest_rand_syscall(uint8_t *out, size_t out_len)
-{
- tor_assert(out_len <= MAX_STRONGEST_RAND_SIZE);
-
- /* We only log at notice-level here because in the case that this function
- * fails the crypto_strongest_rand_raw() caller will log with a warning-level
- * message and let crypto_strongest_rand() error out and finally terminating
- * Tor with an assertion error.
- */
-
-#ifdef TOR_UNIT_TESTS
- if (break_strongest_rng_syscall)
- return -1;
-#endif
-
-#if defined(_WIN32)
- static int provider_set = 0;
- static HCRYPTPROV provider;
-
- if (!provider_set) {
- if (!CryptAcquireContext(&provider, NULL, NULL, PROV_RSA_FULL,
- CRYPT_VERIFYCONTEXT)) {
- log_notice(LD_CRYPTO, "Unable to set Windows CryptoAPI provider [1].");
- return -1;
- }
- provider_set = 1;
- }
- if (!CryptGenRandom(provider, out_len, out)) {
- log_notice(LD_CRYPTO, "Unable get entropy from the Windows CryptoAPI.");
- return -1;
- }
-
- return 0;
-#elif defined(__linux__) && defined(SYS_getrandom)
- static int getrandom_works = 1; /* Be optimistic about our chances... */
-
- /* getrandom() isn't as straightforward as getentropy(), and has
- * no glibc wrapper.
- *
- * As far as I can tell from getrandom(2) and the source code, the
- * requests we issue will always succeed (though it will block on the
- * call if /dev/urandom isn't seeded yet), since we are NOT specifying
- * GRND_NONBLOCK and the request is <= 256 bytes.
- *
- * The manpage is unclear on what happens if a signal interrupts the call
- * while the request is blocked due to lack of entropy....
- *
- * We optimistically assume that getrandom() is available and functional
- * because it is the way of the future, and 2 branch mispredicts pale in
- * comparison to the overheads involved with failing to open
- * /dev/srandom followed by opening and reading from /dev/urandom.
- */
- if (PREDICT_LIKELY(getrandom_works)) {
- long ret;
- /* A flag of '0' here means to read from '/dev/urandom', and to
- * block if insufficient entropy is available to service the
- * request.
- */
- const unsigned int flags = 0;
- do {
- ret = syscall(SYS_getrandom, out, out_len, flags);
- } while (ret == -1 && ((errno == EINTR) ||(errno == EAGAIN)));
-
- if (PREDICT_UNLIKELY(ret == -1)) {
- /* LCOV_EXCL_START we can't actually make the syscall fail in testing. */
- tor_assert(errno != EAGAIN);
- tor_assert(errno != EINTR);
-
- /* Useful log message for errno. */
- if (errno == ENOSYS) {
- log_notice(LD_CRYPTO, "Can't get entropy from getrandom()."
- " You are running a version of Tor built to support"
- " getrandom(), but the kernel doesn't implement this"
- " function--probably because it is too old?"
- " Trying fallback method instead.");
- } else {
- log_notice(LD_CRYPTO, "Can't get entropy from getrandom(): %s."
- " Trying fallback method instead.",
- strerror(errno));
- }
-
- getrandom_works = 0; /* Don't bother trying again. */
- return -1;
- /* LCOV_EXCL_STOP */
- }
-
- tor_assert(ret == (long)out_len);
- return 0;
- }
-
- return -1; /* getrandom() previously failed unexpectedly. */
-#elif defined(HAVE_GETENTROPY)
- /* getentropy() is what Linux's getrandom() wants to be when it grows up.
- * the only gotcha is that requests are limited to 256 bytes.
- */
- return getentropy(out, out_len);
-#else
- (void) out;
-#endif /* defined(_WIN32) || ... */
-
- /* This platform doesn't have a supported syscall based random. */
- return -1;
-}
-
-/** Try to get <b>out_len</b> bytes of the strongest entropy we can generate,
- * via the per-platform fallback mechanism, storing it into <b>out</b>.
- * Return 0 on success, -1 on failure. A maximum request size of 256 bytes
- * is imposed.
- */
-static int
-crypto_strongest_rand_fallback(uint8_t *out, size_t out_len)
-{
-#ifdef TOR_UNIT_TESTS
- if (break_strongest_rng_fallback)
- return -1;
-#endif
-
-#ifdef _WIN32
- /* Windows exclusively uses crypto_strongest_rand_syscall(). */
- (void)out;
- (void)out_len;
- return -1;
-#else /* !(defined(_WIN32)) */
- static const char *filenames[] = {
- "/dev/srandom", "/dev/urandom", "/dev/random", NULL
- };
- int fd, i;
- size_t n;
-
- for (i = 0; filenames[i]; ++i) {
- log_debug(LD_FS, "Considering %s as entropy source", filenames[i]);
- fd = open(sandbox_intern_string(filenames[i]), O_RDONLY, 0);
- if (fd<0) continue;
- log_info(LD_CRYPTO, "Reading entropy from \"%s\"", filenames[i]);
- n = read_all(fd, (char*)out, out_len, 0);
- close(fd);
- if (n != out_len) {
- /* LCOV_EXCL_START
- * We can't make /dev/foorandom actually fail. */
- log_notice(LD_CRYPTO,
- "Error reading from entropy source %s (read only %lu bytes).",
- filenames[i],
- (unsigned long)n);
- return -1;
- /* LCOV_EXCL_STOP */
- }
-
- return 0;
- }
-
- return -1;
-#endif /* defined(_WIN32) */
-}
-
-/** Try to get <b>out_len</b> bytes of the strongest entropy we can generate,
- * storing it into <b>out</b>. Return 0 on success, -1 on failure. A maximum
- * request size of 256 bytes is imposed.
- */
-STATIC int
-crypto_strongest_rand_raw(uint8_t *out, size_t out_len)
-{
- static const size_t sanity_min_size = 16;
- static const int max_attempts = 3;
- tor_assert(out_len <= MAX_STRONGEST_RAND_SIZE);
-
- /* For buffers >= 16 bytes (128 bits), we sanity check the output by
- * zero filling the buffer and ensuring that it actually was at least
- * partially modified.
- *
- * Checking that any individual byte is non-zero seems like it would
- * fail too often (p = out_len * 1/256) for comfort, but this is an
- * "adjust according to taste" sort of check.
- */
- memwipe(out, 0, out_len);
- for (int i = 0; i < max_attempts; i++) {
- /* Try to use the syscall/OS favored mechanism to get strong entropy. */
- if (crypto_strongest_rand_syscall(out, out_len) != 0) {
- /* Try to use the less-favored mechanism to get strong entropy. */
- if (crypto_strongest_rand_fallback(out, out_len) != 0) {
- /* Welp, we tried. Hopefully the calling code terminates the process
- * since we're basically boned without good entropy.
- */
- log_warn(LD_CRYPTO,
- "Cannot get strong entropy: no entropy source found.");
- return -1;
- }
- }
-
- if ((out_len < sanity_min_size) || !tor_mem_is_zero((char*)out, out_len))
- return 0;
- }
-
- /* LCOV_EXCL_START
- *
- * We tried max_attempts times to fill a buffer >= 128 bits long,
- * and each time it returned all '0's. Either the system entropy
- * source is busted, or the user should go out and buy a ticket to
- * every lottery on the planet.
- */
- log_warn(LD_CRYPTO, "Strong OS entropy returned all zero buffer.");
-
- return -1;
- /* LCOV_EXCL_STOP */
-}
-
-/** Try to get <b>out_len</b> bytes of the strongest entropy we can generate,
- * storing it into <b>out</b>.
- */
-void
-crypto_strongest_rand(uint8_t *out, size_t out_len)
-{
-#define DLEN SHA512_DIGEST_LENGTH
- /* We're going to hash DLEN bytes from the system RNG together with some
- * bytes from the openssl PRNG, in order to yield DLEN bytes.
- */
- uint8_t inp[DLEN*2];
- uint8_t tmp[DLEN];
- tor_assert(out);
- while (out_len) {
- crypto_rand((char*) inp, DLEN);
- if (crypto_strongest_rand_raw(inp+DLEN, DLEN) < 0) {
- // LCOV_EXCL_START
- log_err(LD_CRYPTO, "Failed to load strong entropy when generating an "
- "important key. Exiting.");
- /* Die with an assertion so we get a stack trace. */
- tor_assert(0);
- // LCOV_EXCL_STOP
- }
- if (out_len >= DLEN) {
- SHA512(inp, sizeof(inp), out);
- out += DLEN;
- out_len -= DLEN;
- } else {
- SHA512(inp, sizeof(inp), tmp);
- memcpy(out, tmp, out_len);
- break;
- }
- }
- memwipe(tmp, 0, sizeof(tmp));
- memwipe(inp, 0, sizeof(inp));
-#undef DLEN
-}
-
-/** Seed OpenSSL's random number generator with bytes from the operating
- * system. Return 0 on success, -1 on failure.
- */
-int
-crypto_seed_rng(void)
-{
- int rand_poll_ok = 0, load_entropy_ok = 0;
- uint8_t buf[ADD_ENTROPY];
-
- /* OpenSSL has a RAND_poll function that knows about more kinds of
- * entropy than we do. We'll try calling that, *and* calling our own entropy
- * functions. If one succeeds, we'll accept the RNG as seeded. */
- rand_poll_ok = RAND_poll();
- if (rand_poll_ok == 0)
- log_warn(LD_CRYPTO, "RAND_poll() failed."); // LCOV_EXCL_LINE
-
- load_entropy_ok = !crypto_strongest_rand_raw(buf, sizeof(buf));
- if (load_entropy_ok) {
- RAND_seed(buf, sizeof(buf));
- }
-
- memwipe(buf, 0, sizeof(buf));
-
- if ((rand_poll_ok || load_entropy_ok) && RAND_status() == 1)
- return 0;
- else
- return -1;
-}
-
-/** Write <b>n</b> bytes of strong random data to <b>to</b>. Supports mocking
- * for unit tests.
- *
- * This function is not allowed to fail; if it would fail to generate strong
- * entropy, it must terminate the process instead.
- */
-MOCK_IMPL(void,
-crypto_rand, (char *to, size_t n))
-{
- crypto_rand_unmocked(to, n);
-}
-
-/** Write <b>n</b> bytes of strong random data to <b>to</b>. Most callers
- * will want crypto_rand instead.
- *
- * This function is not allowed to fail; if it would fail to generate strong
- * entropy, it must terminate the process instead.
- */
-void
-crypto_rand_unmocked(char *to, size_t n)
-{
- int r;
- if (n == 0)
- return;
-
- tor_assert(n < INT_MAX);
- tor_assert(to);
- r = RAND_bytes((unsigned char*)to, (int)n);
- /* We consider a PRNG failure non-survivable. Let's assert so that we get a
- * stack trace about where it happened.
- */
- tor_assert(r >= 0);
-}
-
-/** Return a pseudorandom integer, chosen uniformly from the values
- * between 0 and <b>max</b>-1 inclusive. <b>max</b> must be between 1 and
- * INT_MAX+1, inclusive. */
-int
-crypto_rand_int(unsigned int max)
-{
- unsigned int val;
- unsigned int cutoff;
- tor_assert(max <= ((unsigned int)INT_MAX)+1);
- tor_assert(max > 0); /* don't div by 0 */
-
- /* We ignore any values that are >= 'cutoff,' to avoid biasing the
- * distribution with clipping at the upper end of unsigned int's
- * range.
- */
- cutoff = UINT_MAX - (UINT_MAX%max);
- while (1) {
- crypto_rand((char*)&val, sizeof(val));
- if (val < cutoff)
- return val % max;
- }
-}
-
-/** Return a pseudorandom integer, chosen uniformly from the values i such
- * that min <= i < max.
- *
- * <b>min</b> MUST be in range [0, <b>max</b>).
- * <b>max</b> MUST be in range (min, INT_MAX].
- */
-int
-crypto_rand_int_range(unsigned int min, unsigned int max)
-{
- tor_assert(min < max);
- tor_assert(max <= INT_MAX);
-
- /* The overflow is avoided here because crypto_rand_int() returns a value
- * between 0 and (max - min) inclusive. */
- return min + crypto_rand_int(max - min);
-}
-
-/** As crypto_rand_int_range, but supports uint64_t. */
-uint64_t
-crypto_rand_uint64_range(uint64_t min, uint64_t max)
-{
- tor_assert(min < max);
- return min + crypto_rand_uint64(max - min);
-}
-
-/** As crypto_rand_int_range, but supports time_t. */
-time_t
-crypto_rand_time_range(time_t min, time_t max)
-{
- tor_assert(min < max);
- return min + (time_t)crypto_rand_uint64(max - min);
-}
-
-/** Return a pseudorandom 64-bit integer, chosen uniformly from the values
- * between 0 and <b>max</b>-1 inclusive. */
-uint64_t
-crypto_rand_uint64(uint64_t max)
-{
- uint64_t val;
- uint64_t cutoff;
- tor_assert(max < UINT64_MAX);
- tor_assert(max > 0); /* don't div by 0 */
-
- /* We ignore any values that are >= 'cutoff,' to avoid biasing the
- * distribution with clipping at the upper end of unsigned int's
- * range.
- */
- cutoff = UINT64_MAX - (UINT64_MAX%max);
- while (1) {
- crypto_rand((char*)&val, sizeof(val));
- if (val < cutoff)
- return val % max;
- }
-}
-
-/** Return a pseudorandom double d, chosen uniformly from the range
- * 0.0 <= d < 1.0.
- */
-double
-crypto_rand_double(void)
-{
- /* We just use an unsigned int here; we don't really care about getting
- * more than 32 bits of resolution */
- unsigned int u;
- crypto_rand((char*)&u, sizeof(u));
-#if SIZEOF_INT == 4
-#define UINT_MAX_AS_DOUBLE 4294967296.0
-#elif SIZEOF_INT == 8
-#define UINT_MAX_AS_DOUBLE 1.8446744073709552e+19
-#else
-#error SIZEOF_INT is neither 4 nor 8
-#endif /* SIZEOF_INT == 4 || ... */
- return ((double)u) / UINT_MAX_AS_DOUBLE;
-}
-
-/** Generate and return a new random hostname starting with <b>prefix</b>,
- * ending with <b>suffix</b>, and containing no fewer than
- * <b>min_rand_len</b> and no more than <b>max_rand_len</b> random base32
- * characters. Does not check for failure.
- *
- * Clip <b>max_rand_len</b> to MAX_DNS_LABEL_SIZE.
- **/
-char *
-crypto_random_hostname(int min_rand_len, int max_rand_len, const char *prefix,
- const char *suffix)
-{
- char *result, *rand_bytes;
- int randlen, rand_bytes_len;
- size_t resultlen, prefixlen;
-
- if (max_rand_len > MAX_DNS_LABEL_SIZE)
- max_rand_len = MAX_DNS_LABEL_SIZE;
- if (min_rand_len > max_rand_len)
- min_rand_len = max_rand_len;
-
- randlen = crypto_rand_int_range(min_rand_len, max_rand_len+1);
-
- prefixlen = strlen(prefix);
- resultlen = prefixlen + strlen(suffix) + randlen + 16;
-
- rand_bytes_len = ((randlen*5)+7)/8;
- if (rand_bytes_len % 5)
- rand_bytes_len += 5 - (rand_bytes_len%5);
- rand_bytes = tor_malloc(rand_bytes_len);
- crypto_rand(rand_bytes, rand_bytes_len);
-
- result = tor_malloc(resultlen);
- memcpy(result, prefix, prefixlen);
- base32_encode(result+prefixlen, resultlen-prefixlen,
- rand_bytes, rand_bytes_len);
- tor_free(rand_bytes);
- strlcpy(result+prefixlen+randlen, suffix, resultlen-(prefixlen+randlen));
-
- return result;
-}
-
-/** Return a randomly chosen element of <b>sl</b>; or NULL if <b>sl</b>
- * is empty. */
-void *
-smartlist_choose(const smartlist_t *sl)
-{
- int len = smartlist_len(sl);
- if (len)
- return smartlist_get(sl,crypto_rand_int(len));
- return NULL; /* no elements to choose from */
-}
-
-/** Scramble the elements of <b>sl</b> into a random order. */
-void
-smartlist_shuffle(smartlist_t *sl)
-{
- int i;
- /* From the end of the list to the front, choose at random from the
- positions we haven't looked at yet, and swap that position into the
- current position. Remember to give "no swap" the same probability as
- any other swap. */
- for (i = smartlist_len(sl)-1; i > 0; --i) {
- int j = crypto_rand_int(i+1);
- smartlist_swap(sl, i, j);
- }
-}
-
-/**
- * Destroy the <b>sz</b> bytes of data stored at <b>mem</b>, setting them to
- * the value <b>byte</b>.
- * If <b>mem</b> is NULL or <b>sz</b> is zero, nothing happens.
- *
- * This function is preferable to memset, since many compilers will happily
- * optimize out memset() when they can convince themselves that the data being
- * cleared will never be read.
- *
- * Right now, our convention is to use this function when we are wiping data
- * that's about to become inaccessible, such as stack buffers that are about
- * to go out of scope or structures that are about to get freed. (In
- * practice, it appears that the compilers we're currently using will optimize
- * out the memset()s for stack-allocated buffers, but not those for
- * about-to-be-freed structures. That could change, though, so we're being
- * wary.) If there are live reads for the data, then you can just use
- * memset().
- */
-void
-memwipe(void *mem, uint8_t byte, size_t sz)
-{
- if (sz == 0) {
- return;
- }
- /* If sz is nonzero, then mem must not be NULL. */
- tor_assert(mem != NULL);
-
- /* Data this large is likely to be an underflow. */
- tor_assert(sz < SIZE_T_CEILING);
-
- /* Because whole-program-optimization exists, we may not be able to just
- * have this function call "memset". A smart compiler could inline it, then
- * eliminate dead memsets, and declare itself to be clever. */
-
-#if defined(SecureZeroMemory) || defined(HAVE_SECUREZEROMEMORY)
- /* Here's what you do on windows. */
- SecureZeroMemory(mem,sz);
-#elif defined(HAVE_RTLSECUREZEROMEMORY)
- RtlSecureZeroMemory(mem,sz);
-#elif defined(HAVE_EXPLICIT_BZERO)
- /* The BSDs provide this. */
- explicit_bzero(mem, sz);
-#elif defined(HAVE_MEMSET_S)
- /* This is in the C99 standard. */
- memset_s(mem, sz, 0, sz);
-#else
- /* This is a slow and ugly function from OpenSSL that fills 'mem' with junk
- * based on the pointer value, then uses that junk to update a global
- * variable. It's an elaborate ruse to trick the compiler into not
- * optimizing out the "wipe this memory" code. Read it if you like zany
- * programming tricks! In later versions of Tor, we should look for better
- * not-optimized-out memory wiping stuff...
- *
- * ...or maybe not. In practice, there are pure-asm implementations of
- * OPENSSL_cleanse() on most platforms, which ought to do the job.
- **/
-
- OPENSSL_cleanse(mem, sz);
-#endif /* defined(SecureZeroMemory) || defined(HAVE_SECUREZEROMEMORY) || ... */
-
- /* Just in case some caller of memwipe() is relying on getting a buffer
- * filled with a particular value, fill the buffer.
- *
- * If this function gets inlined, this memset might get eliminated, but
- * that's okay: We only care about this particular memset in the case where
- * the caller should have been using memset(), and the memset() wouldn't get
- * eliminated. In other words, this is here so that we won't break anything
- * if somebody accidentally calls memwipe() instead of memset().
- **/
- memset(mem, byte, sz);
-}
-
/** @{ */
/** Uninitialize the crypto library. Return 0 on success. Does not detect
* failure.
@@ -1660,11 +1062,15 @@ memwipe(void *mem, uint8_t byte, size_t sz)
int
crypto_global_cleanup(void)
{
+#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(1,1,0)
EVP_cleanup();
+#endif
#ifndef NEW_THREAD_API
ERR_remove_thread_state(NULL);
#endif
+#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(1,1,0)
ERR_free_strings();
+#endif
if (dh_param_p)
BN_clear_free(dh_param_p);
@@ -1676,11 +1082,15 @@ crypto_global_cleanup(void)
dh_param_p = dh_param_p_tls = dh_param_g = NULL;
#ifndef DISABLE_ENGINES
+#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(1,1,0)
ENGINE_cleanup();
#endif
+#endif
CONF_modules_unload(1);
+#if OPENSSL_VERSION_NUMBER < OPENSSL_V_SERIES(1,1,0)
CRYPTO_cleanup_all_ex_data();
+#endif
crypto_openssl_free_all();
diff --git a/src/common/crypto.h b/src/common/crypto.h
index b586790329..c773557310 100644
--- a/src/common/crypto.h
+++ b/src/common/crypto.h
@@ -17,13 +17,10 @@
#include <stdio.h>
#include "torint.h"
-#include "testsupport.h"
#include "compat.h"
#include "util.h"
#include "crypto_rsa.h"
-#include "keccak-tiny/keccak-tiny.h"
-
/** Length of our symmetric cipher's keys of 128-bit. */
#define CIPHER_KEY_LEN 16
/** Length of our symmetric cipher's IV of 128-bit. */
@@ -41,6 +38,7 @@ typedef struct aes_cnt_cipher crypto_cipher_t;
typedef struct crypto_dh_t crypto_dh_t;
/* global state */
+int crypto_init_siphash_key(void);
int crypto_early_init(void) ATTR_WUR;
int crypto_global_init(int hardwareAccel,
const char *accelName,
@@ -105,31 +103,6 @@ int crypto_expand_key_material_rfc5869_sha256(
const uint8_t *info_in, size_t info_in_len,
uint8_t *key_out, size_t key_out_len);
-/* random numbers */
-int crypto_seed_rng(void) ATTR_WUR;
-MOCK_DECL(void,crypto_rand,(char *to, size_t n));
-void crypto_rand_unmocked(char *to, size_t n);
-void crypto_strongest_rand(uint8_t *out, size_t out_len);
-int crypto_rand_int(unsigned int max);
-int crypto_rand_int_range(unsigned int min, unsigned int max);
-uint64_t crypto_rand_uint64_range(uint64_t min, uint64_t max);
-time_t crypto_rand_time_range(time_t min, time_t max);
-uint64_t crypto_rand_uint64(uint64_t max);
-double crypto_rand_double(void);
-struct tor_weak_rng_t;
-void crypto_seed_weak_rng(struct tor_weak_rng_t *rng);
-int crypto_init_siphash_key(void);
-
-char *crypto_random_hostname(int min_rand_len, int max_rand_len,
- const char *prefix, const char *suffix);
-
-struct smartlist_t;
-void *smartlist_choose(const struct smartlist_t *sl);
-void smartlist_shuffle(struct smartlist_t *sl);
-
-/** OpenSSL-based utility functions. */
-void memwipe(void *mem, uint8_t byte, size_t sz);
-
/* Prototypes for private functions only used by tortls.c, crypto.c, and the
* unit tests. */
struct dh_st;
@@ -137,16 +110,5 @@ struct dh_st *crypto_dh_get_dh_(crypto_dh_t *dh);
void crypto_add_spaces_to_fp(char *out, size_t outlen, const char *in);
-#ifdef CRYPTO_PRIVATE
-
-STATIC int crypto_force_rand_ssleay(void);
-STATIC int crypto_strongest_rand_raw(uint8_t *out, size_t out_len);
-
-#ifdef TOR_UNIT_TESTS
-extern int break_strongest_rng_syscall;
-extern int break_strongest_rng_fallback;
-#endif
-#endif /* defined(CRYPTO_PRIVATE) */
-
#endif /* !defined(TOR_CRYPTO_H) */
diff --git a/src/common/crypto_curve25519.c b/src/common/crypto_curve25519.c
index ccf12d00f9..996d94c6e2 100644
--- a/src/common/crypto_curve25519.c
+++ b/src/common/crypto_curve25519.c
@@ -21,10 +21,11 @@
#include <sys/stat.h>
#endif
#include "container.h"
-#include "crypto.h"
#include "crypto_curve25519.h"
-#include "crypto_format.h"
#include "crypto_digest.h"
+#include "crypto_format.h"
+#include "crypto_rand.h"
+#include "crypto_util.h"
#include "util.h"
#include "torlog.h"
diff --git a/src/common/crypto_digest.c b/src/common/crypto_digest.c
index cdcc1828c8..f7163de133 100644
--- a/src/common/crypto_digest.c
+++ b/src/common/crypto_digest.c
@@ -10,10 +10,13 @@
* operations.
**/
+#include "container.h"
#include "crypto_digest.h"
-
-#include "crypto.h" /* common functions */
#include "crypto_openssl_mgt.h"
+#include "crypto_util.h"
+#include "torlog.h"
+
+#include "keccak-tiny/keccak-tiny.h"
DISABLE_GCC_WARNING(redundant-decls)
@@ -22,8 +25,6 @@ DISABLE_GCC_WARNING(redundant-decls)
ENABLE_GCC_WARNING(redundant-decls)
-#include "container.h"
-
/* Crypto digest functions */
/** Compute the SHA1 digest of the <b>len</b> bytes on data stored in
diff --git a/src/common/crypto_ed25519.c b/src/common/crypto_ed25519.c
index f1cc0cb188..9c13e3bdf0 100644
--- a/src/common/crypto_ed25519.c
+++ b/src/common/crypto_ed25519.c
@@ -21,12 +21,12 @@
#include <sys/stat.h>
#endif
-#include "crypto.h"
-
-#include "crypto_digest.h"
#include "crypto_curve25519.h"
+#include "crypto_digest.h"
#include "crypto_ed25519.h"
#include "crypto_format.h"
+#include "crypto_rand.h"
+#include "crypto_util.h"
#include "torlog.h"
#include "util.h"
#include "util_format.h"
diff --git a/src/common/crypto_format.c b/src/common/crypto_format.c
index 3f6fb9f54c..460e85bac1 100644
--- a/src/common/crypto_format.c
+++ b/src/common/crypto_format.c
@@ -15,11 +15,11 @@
#include <sys/stat.h>
#endif
#include "container.h"
-#include "crypto.h"
#include "crypto_curve25519.h"
+#include "crypto_digest.h"
#include "crypto_ed25519.h"
#include "crypto_format.h"
-#include "crypto_digest.h"
+#include "crypto_util.h"
#include "util.h"
#include "util_format.h"
#include "torlog.h"
diff --git a/src/common/crypto_pwbox.c b/src/common/crypto_pwbox.c
index 604fc68e97..c2bd1d26cb 100644
--- a/src/common/crypto_pwbox.c
+++ b/src/common/crypto_pwbox.c
@@ -9,9 +9,11 @@
*/
#include "crypto.h"
-#include "crypto_s2k.h"
-#include "crypto_pwbox.h"
#include "crypto_digest.h"
+#include "crypto_pwbox.h"
+#include "crypto_rand.h"
+#include "crypto_s2k.h"
+#include "crypto_util.h"
#include "di_ops.h"
#include "util.h"
#include "pwbox.h"
diff --git a/src/common/crypto_rand.c b/src/common/crypto_rand.c
new file mode 100644
index 0000000000..df2e2f65d3
--- /dev/null
+++ b/src/common/crypto_rand.c
@@ -0,0 +1,615 @@
+/* Copyright (c) 2001, Matej Pfajfar.
+ * Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file crypto_rand.c
+ *
+ * \brief Functions for initialising and seeding (pseudo-)random
+ * number generators, and working with randomness.
+ **/
+
+#ifndef CRYPTO_RAND_PRIVATE
+#define CRYPTO_RAND_PRIVATE
+
+#include "crypto_rand.h"
+
+#ifdef _WIN32
+#include <windows.h>
+#include <wincrypt.h>
+#endif /* defined(_WIN32) */
+
+#include "container.h"
+#include "compat.h"
+#include "compat_openssl.h"
+#include "crypto_util.h"
+#include "sandbox.h"
+#include "testsupport.h"
+#include "torlog.h"
+#include "util.h"
+#include "util_format.h"
+
+DISABLE_GCC_WARNING(redundant-decls)
+#include <openssl/rand.h>
+ENABLE_GCC_WARNING(redundant-decls)
+
+#if __GNUC__ && GCC_VERSION >= 402
+#if GCC_VERSION >= 406
+#pragma GCC diagnostic pop
+#else
+#pragma GCC diagnostic warning "-Wredundant-decls"
+#endif
+#endif /* __GNUC__ && GCC_VERSION >= 402 */
+
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+#ifdef HAVE_SYS_FCNTL_H
+#include <sys/fcntl.h>
+#endif
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_SYS_SYSCALL_H
+#include <sys/syscall.h>
+#endif
+#ifdef HAVE_SYS_RANDOM_H
+#include <sys/random.h>
+#endif
+
+/**
+ * How many bytes of entropy we add at once.
+ *
+ * This is how much entropy OpenSSL likes to add right now, so maybe it will
+ * work for us too.
+ **/
+#define ADD_ENTROPY 32
+
+/**
+ * Longest recognized DNS query.
+ **/
+#define MAX_DNS_LABEL_SIZE 63
+
+/**
+ * Largest strong entropy request permitted.
+ **/
+#define MAX_STRONGEST_RAND_SIZE 256
+
+/**
+ * Set the seed of the weak RNG to a random value.
+ **/
+void
+crypto_seed_weak_rng(tor_weak_rng_t *rng)
+{
+ unsigned seed;
+ crypto_rand((void*)&seed, sizeof(seed));
+ tor_init_weak_random(rng, seed);
+}
+
+#ifdef TOR_UNIT_TESTS
+int break_strongest_rng_syscall = 0;
+int break_strongest_rng_fallback = 0;
+#endif
+
+/**
+ * Try to get <b>out_len</b> bytes of the strongest entropy we can generate,
+ * via system calls, storing it into <b>out</b>. Return 0 on success, -1 on
+ * failure. A maximum request size of 256 bytes is imposed.
+ **/
+static int
+crypto_strongest_rand_syscall(uint8_t *out, size_t out_len)
+{
+ tor_assert(out_len <= MAX_STRONGEST_RAND_SIZE);
+
+ /* We only log at notice-level here because in the case that this function
+ * fails the crypto_strongest_rand_raw() caller will log with a warning-level
+ * message and let crypto_strongest_rand() error out and finally terminating
+ * Tor with an assertion error.
+ */
+
+#ifdef TOR_UNIT_TESTS
+ if (break_strongest_rng_syscall)
+ return -1;
+#endif
+
+#if defined(_WIN32)
+ static int provider_set = 0;
+ static HCRYPTPROV provider;
+
+ if (!provider_set) {
+ if (!CryptAcquireContext(&provider, NULL, NULL, PROV_RSA_FULL,
+ CRYPT_VERIFYCONTEXT)) {
+ log_notice(LD_CRYPTO, "Unable to set Windows CryptoAPI provider [1].");
+ return -1;
+ }
+ provider_set = 1;
+ }
+ if (!CryptGenRandom(provider, out_len, out)) {
+ log_notice(LD_CRYPTO, "Unable get entropy from the Windows CryptoAPI.");
+ return -1;
+ }
+
+ return 0;
+#elif defined(__linux__) && defined(SYS_getrandom)
+ static int getrandom_works = 1; /* Be optimistic about our chances... */
+
+ /* getrandom() isn't as straightforward as getentropy(), and has
+ * no glibc wrapper.
+ *
+ * As far as I can tell from getrandom(2) and the source code, the
+ * requests we issue will always succeed (though it will block on the
+ * call if /dev/urandom isn't seeded yet), since we are NOT specifying
+ * GRND_NONBLOCK and the request is <= 256 bytes.
+ *
+ * The manpage is unclear on what happens if a signal interrupts the call
+ * while the request is blocked due to lack of entropy....
+ *
+ * We optimistically assume that getrandom() is available and functional
+ * because it is the way of the future, and 2 branch mispredicts pale in
+ * comparison to the overheads involved with failing to open
+ * /dev/srandom followed by opening and reading from /dev/urandom.
+ */
+ if (PREDICT_LIKELY(getrandom_works)) {
+ long ret;
+ /* A flag of '0' here means to read from '/dev/urandom', and to
+ * block if insufficient entropy is available to service the
+ * request.
+ */
+ const unsigned int flags = 0;
+ do {
+ ret = syscall(SYS_getrandom, out, out_len, flags);
+ } while (ret == -1 && ((errno == EINTR) ||(errno == EAGAIN)));
+
+ if (PREDICT_UNLIKELY(ret == -1)) {
+ /* LCOV_EXCL_START we can't actually make the syscall fail in testing. */
+ tor_assert(errno != EAGAIN);
+ tor_assert(errno != EINTR);
+
+ /* Useful log message for errno. */
+ if (errno == ENOSYS) {
+ log_notice(LD_CRYPTO, "Can't get entropy from getrandom()."
+ " You are running a version of Tor built to support"
+ " getrandom(), but the kernel doesn't implement this"
+ " function--probably because it is too old?"
+ " Trying fallback method instead.");
+ } else {
+ log_notice(LD_CRYPTO, "Can't get entropy from getrandom(): %s."
+ " Trying fallback method instead.",
+ strerror(errno));
+ }
+
+ getrandom_works = 0; /* Don't bother trying again. */
+ return -1;
+ /* LCOV_EXCL_STOP */
+ }
+
+ tor_assert(ret == (long)out_len);
+ return 0;
+ }
+
+ return -1; /* getrandom() previously failed unexpectedly. */
+#elif defined(HAVE_GETENTROPY)
+ /* getentropy() is what Linux's getrandom() wants to be when it grows up.
+ * the only gotcha is that requests are limited to 256 bytes.
+ */
+ return getentropy(out, out_len);
+#else
+ (void) out;
+#endif /* defined(_WIN32) || ... */
+
+ /* This platform doesn't have a supported syscall based random. */
+ return -1;
+}
+
+/**
+ * Try to get <b>out_len</b> bytes of the strongest entropy we can generate,
+ * via the per-platform fallback mechanism, storing it into <b>out</b>.
+ * Return 0 on success, -1 on failure. A maximum request size of 256 bytes
+ * is imposed.
+ **/
+static int
+crypto_strongest_rand_fallback(uint8_t *out, size_t out_len)
+{
+#ifdef TOR_UNIT_TESTS
+ if (break_strongest_rng_fallback)
+ return -1;
+#endif
+
+#ifdef _WIN32
+ /* Windows exclusively uses crypto_strongest_rand_syscall(). */
+ (void)out;
+ (void)out_len;
+ return -1;
+#else /* !(defined(_WIN32)) */
+ static const char *filenames[] = {
+ "/dev/srandom", "/dev/urandom", "/dev/random", NULL
+ };
+ int fd, i;
+ size_t n;
+
+ for (i = 0; filenames[i]; ++i) {
+ log_debug(LD_FS, "Considering %s as entropy source", filenames[i]);
+ fd = open(sandbox_intern_string(filenames[i]), O_RDONLY, 0);
+ if (fd<0) continue;
+ log_info(LD_CRYPTO, "Reading entropy from \"%s\"", filenames[i]);
+ n = read_all(fd, (char*)out, out_len, 0);
+ close(fd);
+ if (n != out_len) {
+ /* LCOV_EXCL_START
+ * We can't make /dev/foorandom actually fail. */
+ log_notice(LD_CRYPTO,
+ "Error reading from entropy source %s (read only %lu bytes).",
+ filenames[i],
+ (unsigned long)n);
+ return -1;
+ /* LCOV_EXCL_STOP */
+ }
+
+ return 0;
+ }
+
+ return -1;
+#endif /* defined(_WIN32) */
+}
+
+/**
+ * Try to get <b>out_len</b> bytes of the strongest entropy we can generate,
+ * storing it into <b>out</b>. Return 0 on success, -1 on failure. A maximum
+ * request size of 256 bytes is imposed.
+ **/
+STATIC int
+crypto_strongest_rand_raw(uint8_t *out, size_t out_len)
+{
+ static const size_t sanity_min_size = 16;
+ static const int max_attempts = 3;
+ tor_assert(out_len <= MAX_STRONGEST_RAND_SIZE);
+
+ /* For buffers >= 16 bytes (128 bits), we sanity check the output by
+ * zero filling the buffer and ensuring that it actually was at least
+ * partially modified.
+ *
+ * Checking that any individual byte is non-zero seems like it would
+ * fail too often (p = out_len * 1/256) for comfort, but this is an
+ * "adjust according to taste" sort of check.
+ */
+ memwipe(out, 0, out_len);
+ for (int i = 0; i < max_attempts; i++) {
+ /* Try to use the syscall/OS favored mechanism to get strong entropy. */
+ if (crypto_strongest_rand_syscall(out, out_len) != 0) {
+ /* Try to use the less-favored mechanism to get strong entropy. */
+ if (crypto_strongest_rand_fallback(out, out_len) != 0) {
+ /* Welp, we tried. Hopefully the calling code terminates the process
+ * since we're basically boned without good entropy.
+ */
+ log_warn(LD_CRYPTO,
+ "Cannot get strong entropy: no entropy source found.");
+ return -1;
+ }
+ }
+
+ if ((out_len < sanity_min_size) || !tor_mem_is_zero((char*)out, out_len))
+ return 0;
+ }
+
+ /* LCOV_EXCL_START
+ *
+ * We tried max_attempts times to fill a buffer >= 128 bits long,
+ * and each time it returned all '0's. Either the system entropy
+ * source is busted, or the user should go out and buy a ticket to
+ * every lottery on the planet.
+ */
+ log_warn(LD_CRYPTO, "Strong OS entropy returned all zero buffer.");
+
+ return -1;
+ /* LCOV_EXCL_STOP */
+}
+
+/**
+ * Try to get <b>out_len</b> bytes of the strongest entropy we can generate,
+ * storing it into <b>out</b>.
+ **/
+void
+crypto_strongest_rand(uint8_t *out, size_t out_len)
+{
+#define DLEN SHA512_DIGEST_LENGTH
+ /* We're going to hash DLEN bytes from the system RNG together with some
+ * bytes from the openssl PRNG, in order to yield DLEN bytes.
+ */
+ uint8_t inp[DLEN*2];
+ uint8_t tmp[DLEN];
+ tor_assert(out);
+ while (out_len) {
+ crypto_rand((char*) inp, DLEN);
+ if (crypto_strongest_rand_raw(inp+DLEN, DLEN) < 0) {
+ // LCOV_EXCL_START
+ log_err(LD_CRYPTO, "Failed to load strong entropy when generating an "
+ "important key. Exiting.");
+ /* Die with an assertion so we get a stack trace. */
+ tor_assert(0);
+ // LCOV_EXCL_STOP
+ }
+ if (out_len >= DLEN) {
+ SHA512(inp, sizeof(inp), out);
+ out += DLEN;
+ out_len -= DLEN;
+ } else {
+ SHA512(inp, sizeof(inp), tmp);
+ memcpy(out, tmp, out_len);
+ break;
+ }
+ }
+ memwipe(tmp, 0, sizeof(tmp));
+ memwipe(inp, 0, sizeof(inp));
+#undef DLEN
+}
+
+/**
+ * Seed OpenSSL's random number generator with bytes from the operating
+ * system. Return 0 on success, -1 on failure.
+ **/
+int
+crypto_seed_rng(void)
+{
+ int rand_poll_ok = 0, load_entropy_ok = 0;
+ uint8_t buf[ADD_ENTROPY];
+
+ /* OpenSSL has a RAND_poll function that knows about more kinds of
+ * entropy than we do. We'll try calling that, *and* calling our own entropy
+ * functions. If one succeeds, we'll accept the RNG as seeded. */
+ rand_poll_ok = RAND_poll();
+ if (rand_poll_ok == 0)
+ log_warn(LD_CRYPTO, "RAND_poll() failed."); // LCOV_EXCL_LINE
+
+ load_entropy_ok = !crypto_strongest_rand_raw(buf, sizeof(buf));
+ if (load_entropy_ok) {
+ RAND_seed(buf, sizeof(buf));
+ }
+
+ memwipe(buf, 0, sizeof(buf));
+
+ if ((rand_poll_ok || load_entropy_ok) && RAND_status() == 1)
+ return 0;
+ else
+ return -1;
+}
+
+/**
+ * Write <b>n</b> bytes of strong random data to <b>to</b>. Supports mocking
+ * for unit tests.
+ *
+ * This function is not allowed to fail; if it would fail to generate strong
+ * entropy, it must terminate the process instead.
+ **/
+MOCK_IMPL(void,
+crypto_rand, (char *to, size_t n))
+{
+ crypto_rand_unmocked(to, n);
+}
+
+/**
+ * Write <b>n</b> bytes of strong random data to <b>to</b>. Most callers
+ * will want crypto_rand instead.
+ *
+ * This function is not allowed to fail; if it would fail to generate strong
+ * entropy, it must terminate the process instead.
+ **/
+void
+crypto_rand_unmocked(char *to, size_t n)
+{
+ int r;
+ if (n == 0)
+ return;
+
+ tor_assert(n < INT_MAX);
+ tor_assert(to);
+ r = RAND_bytes((unsigned char*)to, (int)n);
+ /* We consider a PRNG failure non-survivable. Let's assert so that we get a
+ * stack trace about where it happened.
+ */
+ tor_assert(r >= 0);
+}
+
+/**
+ * Return a pseudorandom integer, chosen uniformly from the values
+ * between 0 and <b>max</b>-1 inclusive. <b>max</b> must be between 1 and
+ * INT_MAX+1, inclusive.
+ */
+int
+crypto_rand_int(unsigned int max)
+{
+ unsigned int val;
+ unsigned int cutoff;
+ tor_assert(max <= ((unsigned int)INT_MAX)+1);
+ tor_assert(max > 0); /* don't div by 0 */
+
+ /* We ignore any values that are >= 'cutoff,' to avoid biasing the
+ * distribution with clipping at the upper end of unsigned int's
+ * range.
+ */
+ cutoff = UINT_MAX - (UINT_MAX%max);
+ while (1) {
+ crypto_rand((char*)&val, sizeof(val));
+ if (val < cutoff)
+ return val % max;
+ }
+}
+
+/**
+ * Return a pseudorandom integer, chosen uniformly from the values i such
+ * that min <= i < max.
+ *
+ * <b>min</b> MUST be in range [0, <b>max</b>).
+ * <b>max</b> MUST be in range (min, INT_MAX].
+ **/
+int
+crypto_rand_int_range(unsigned int min, unsigned int max)
+{
+ tor_assert(min < max);
+ tor_assert(max <= INT_MAX);
+
+ /* The overflow is avoided here because crypto_rand_int() returns a value
+ * between 0 and (max - min) inclusive. */
+ return min + crypto_rand_int(max - min);
+}
+
+/**
+ * As crypto_rand_int_range, but supports uint64_t.
+ **/
+uint64_t
+crypto_rand_uint64_range(uint64_t min, uint64_t max)
+{
+ tor_assert(min < max);
+ return min + crypto_rand_uint64(max - min);
+}
+
+/**
+ * As crypto_rand_int_range, but supports time_t.
+ **/
+time_t
+crypto_rand_time_range(time_t min, time_t max)
+{
+ tor_assert(min < max);
+ return min + (time_t)crypto_rand_uint64(max - min);
+}
+
+/**
+ * Return a pseudorandom 64-bit integer, chosen uniformly from the values
+ * between 0 and <b>max</b>-1 inclusive.
+ **/
+uint64_t
+crypto_rand_uint64(uint64_t max)
+{
+ uint64_t val;
+ uint64_t cutoff;
+ tor_assert(max < UINT64_MAX);
+ tor_assert(max > 0); /* don't div by 0 */
+
+ /* We ignore any values that are >= 'cutoff,' to avoid biasing the
+ * distribution with clipping at the upper end of unsigned int's
+ * range.
+ */
+ cutoff = UINT64_MAX - (UINT64_MAX%max);
+ while (1) {
+ crypto_rand((char*)&val, sizeof(val));
+ if (val < cutoff)
+ return val % max;
+ }
+}
+
+/**
+ * Return a pseudorandom double d, chosen uniformly from the range
+ * 0.0 <= d < 1.0.
+ **/
+double
+crypto_rand_double(void)
+{
+ /* We just use an unsigned int here; we don't really care about getting
+ * more than 32 bits of resolution */
+ unsigned int u;
+ crypto_rand((char*)&u, sizeof(u));
+#if SIZEOF_INT == 4
+#define UINT_MAX_AS_DOUBLE 4294967296.0
+#elif SIZEOF_INT == 8
+#define UINT_MAX_AS_DOUBLE 1.8446744073709552e+19
+#else
+#error SIZEOF_INT is neither 4 nor 8
+#endif /* SIZEOF_INT == 4 || ... */
+ return ((double)u) / UINT_MAX_AS_DOUBLE;
+}
+
+/**
+ * Generate and return a new random hostname starting with <b>prefix</b>,
+ * ending with <b>suffix</b>, and containing no fewer than
+ * <b>min_rand_len</b> and no more than <b>max_rand_len</b> random base32
+ * characters. Does not check for failure.
+ *
+ * Clip <b>max_rand_len</b> to MAX_DNS_LABEL_SIZE.
+ **/
+char *
+crypto_random_hostname(int min_rand_len, int max_rand_len, const char *prefix,
+ const char *suffix)
+{
+ char *result, *rand_bytes;
+ int randlen, rand_bytes_len;
+ size_t resultlen, prefixlen;
+
+ if (max_rand_len > MAX_DNS_LABEL_SIZE)
+ max_rand_len = MAX_DNS_LABEL_SIZE;
+ if (min_rand_len > max_rand_len)
+ min_rand_len = max_rand_len;
+
+ randlen = crypto_rand_int_range(min_rand_len, max_rand_len+1);
+
+ prefixlen = strlen(prefix);
+ resultlen = prefixlen + strlen(suffix) + randlen + 16;
+
+ rand_bytes_len = ((randlen*5)+7)/8;
+ if (rand_bytes_len % 5)
+ rand_bytes_len += 5 - (rand_bytes_len%5);
+ rand_bytes = tor_malloc(rand_bytes_len);
+ crypto_rand(rand_bytes, rand_bytes_len);
+
+ result = tor_malloc(resultlen);
+ memcpy(result, prefix, prefixlen);
+ base32_encode(result+prefixlen, resultlen-prefixlen,
+ rand_bytes, rand_bytes_len);
+ tor_free(rand_bytes);
+ strlcpy(result+prefixlen+randlen, suffix, resultlen-(prefixlen+randlen));
+
+ return result;
+}
+
+/**
+ * Return a randomly chosen element of <b>sl</b>; or NULL if <b>sl</b>
+ * is empty.
+ **/
+void *
+smartlist_choose(const smartlist_t *sl)
+{
+ int len = smartlist_len(sl);
+ if (len)
+ return smartlist_get(sl,crypto_rand_int(len));
+ return NULL; /* no elements to choose from */
+}
+
+/**
+ * Scramble the elements of <b>sl</b> into a random order.
+ **/
+void
+smartlist_shuffle(smartlist_t *sl)
+{
+ int i;
+ /* From the end of the list to the front, choose at random from the
+ positions we haven't looked at yet, and swap that position into the
+ current position. Remember to give "no swap" the same probability as
+ any other swap. */
+ for (i = smartlist_len(sl)-1; i > 0; --i) {
+ int j = crypto_rand_int(i+1);
+ smartlist_swap(sl, i, j);
+ }
+}
+
+/** Make sure that openssl is using its default PRNG. Return 1 if we had to
+ * adjust it; 0 otherwise. */
+int
+crypto_force_rand_ssleay(void)
+{
+ RAND_METHOD *default_method;
+ default_method = RAND_OpenSSL();
+ if (RAND_get_rand_method() != default_method) {
+ log_notice(LD_CRYPTO, "It appears that one of our engines has provided "
+ "a replacement the OpenSSL RNG. Resetting it to the default "
+ "implementation.");
+ RAND_set_rand_method(default_method);
+ return 1;
+ }
+ return 0;
+}
+
+#endif /* !defined(CRYPTO_RAND_PRIVATE) */
+
diff --git a/src/common/crypto_rand.h b/src/common/crypto_rand.h
new file mode 100644
index 0000000000..4eac94f57b
--- /dev/null
+++ b/src/common/crypto_rand.h
@@ -0,0 +1,52 @@
+/* Copyright (c) 2001, Matej Pfajfar.
+ * Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file crypto_rand.h
+ *
+ * \brief Common functions for using (psuedo-)random number generators.
+ **/
+
+#ifndef TOR_CRYPTO_RAND_H
+#define TOR_CRYPTO_RAND_H
+
+#include "torint.h"
+#include "util.h"
+
+/* random numbers */
+int crypto_seed_rng(void) ATTR_WUR;
+MOCK_DECL(void,crypto_rand,(char *to, size_t n));
+void crypto_rand_unmocked(char *to, size_t n);
+void crypto_strongest_rand(uint8_t *out, size_t out_len);
+int crypto_rand_int(unsigned int max);
+int crypto_rand_int_range(unsigned int min, unsigned int max);
+uint64_t crypto_rand_uint64_range(uint64_t min, uint64_t max);
+time_t crypto_rand_time_range(time_t min, time_t max);
+uint64_t crypto_rand_uint64(uint64_t max);
+double crypto_rand_double(void);
+struct tor_weak_rng_t;
+void crypto_seed_weak_rng(struct tor_weak_rng_t *rng);
+
+char *crypto_random_hostname(int min_rand_len, int max_rand_len,
+ const char *prefix, const char *suffix);
+
+struct smartlist_t;
+void *smartlist_choose(const struct smartlist_t *sl);
+void smartlist_shuffle(struct smartlist_t *sl);
+int crypto_force_rand_ssleay(void);
+
+#ifdef CRYPTO_RAND_PRIVATE
+
+STATIC int crypto_strongest_rand_raw(uint8_t *out, size_t out_len);
+
+#ifdef TOR_UNIT_TESTS
+extern int break_strongest_rng_syscall;
+extern int break_strongest_rng_fallback;
+#endif
+#endif /* defined(CRYPTO_RAND_PRIVATE) */
+
+#endif /* !defined(TOR_CRYPTO_RAND_H) */
+
diff --git a/src/common/crypto_rsa.c b/src/common/crypto_rsa.c
index 986ccb0ee2..0a88b0e772 100644
--- a/src/common/crypto_rsa.c
+++ b/src/common/crypto_rsa.c
@@ -9,12 +9,14 @@
* \brief Block of functions related with RSA utilities and operations.
**/
-#include "crypto_rsa.h"
#include "crypto.h"
-#include "compat_openssl.h"
#include "crypto_curve25519.h"
-#include "crypto_format.h"
#include "crypto_digest.h"
+#include "crypto_format.h"
+#include "compat_openssl.h"
+#include "crypto_rand.h"
+#include "crypto_rsa.h"
+#include "crypto_util.h"
DISABLE_GCC_WARNING(redundant-decls)
diff --git a/src/common/crypto_rsa.h b/src/common/crypto_rsa.h
index 2f5442a5d2..e952089318 100644
--- a/src/common/crypto_rsa.h
+++ b/src/common/crypto_rsa.h
@@ -35,7 +35,7 @@
/** A public key, or a public/private key-pair. */
typedef struct crypto_pk_t crypto_pk_t;
-/* RSA enviroment setup */
+/* RSA environment setup */
MOCK_DECL(crypto_pk_t *,crypto_pk_new,(void));
void crypto_pk_free_(crypto_pk_t *env);
#define crypto_pk_free(pk) FREE_AND_NULL(crypto_pk_t, crypto_pk_free_, (pk))
diff --git a/src/common/crypto_s2k.c b/src/common/crypto_s2k.c
index 316445e40f..8543760ec5 100644
--- a/src/common/crypto_s2k.c
+++ b/src/common/crypto_s2k.c
@@ -12,11 +12,13 @@
#define CRYPTO_S2K_PRIVATE
-#include "crypto.h"
-#include "util.h"
#include "compat.h"
-#include "crypto_s2k.h"
+#include "crypto.h"
#include "crypto_digest.h"
+#include "crypto_rand.h"
+#include "crypto_s2k.h"
+#include "crypto_util.h"
+#include "util.h"
#include <openssl/evp.h>
diff --git a/src/common/crypto_util.c b/src/common/crypto_util.c
new file mode 100644
index 0000000000..b0d5b6b2f7
--- /dev/null
+++ b/src/common/crypto_util.c
@@ -0,0 +1,107 @@
+/* Copyright (c) 2001, Matej Pfajfar.
+ * Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file crypto_util.c
+ *
+ * \brief Common cryptographic utilities.
+ **/
+
+#ifndef CRYPTO_UTIL_PRIVATE
+#define CRYPTO_UTIL_PRIVATE
+
+#include "crypto_util.h"
+
+#include <string.h>
+
+#ifdef _WIN32
+#include <winsock2.h>
+#include <windows.h>
+#include <wincrypt.h>
+#endif /* defined(_WIN32) */
+
+#include "util.h"
+
+DISABLE_GCC_WARNING(redundant-decls)
+
+#include <openssl/crypto.h>
+
+ENABLE_GCC_WARNING(redundant-decls)
+
+/**
+ * Destroy the <b>sz</b> bytes of data stored at <b>mem</b>, setting them to
+ * the value <b>byte</b>.
+ * If <b>mem</b> is NULL or <b>sz</b> is zero, nothing happens.
+ *
+ * This function is preferable to memset, since many compilers will happily
+ * optimize out memset() when they can convince themselves that the data being
+ * cleared will never be read.
+ *
+ * Right now, our convention is to use this function when we are wiping data
+ * that's about to become inaccessible, such as stack buffers that are about
+ * to go out of scope or structures that are about to get freed. (In
+ * practice, it appears that the compilers we're currently using will optimize
+ * out the memset()s for stack-allocated buffers, but not those for
+ * about-to-be-freed structures. That could change, though, so we're being
+ * wary.) If there are live reads for the data, then you can just use
+ * memset().
+ */
+void
+memwipe(void *mem, uint8_t byte, size_t sz)
+{
+ if (sz == 0) {
+ return;
+ }
+ /* If sz is nonzero, then mem must not be NULL. */
+ tor_assert(mem != NULL);
+
+ /* Data this large is likely to be an underflow. */
+ tor_assert(sz < SIZE_T_CEILING);
+
+ /* Because whole-program-optimization exists, we may not be able to just
+ * have this function call "memset". A smart compiler could inline it, then
+ * eliminate dead memsets, and declare itself to be clever. */
+
+#if defined(SecureZeroMemory) || defined(HAVE_SECUREZEROMEMORY)
+ /* Here's what you do on windows. */
+ SecureZeroMemory(mem,sz);
+#elif defined(HAVE_RTLSECUREZEROMEMORY)
+ RtlSecureZeroMemory(mem,sz);
+#elif defined(HAVE_EXPLICIT_BZERO)
+ /* The BSDs provide this. */
+ explicit_bzero(mem, sz);
+#elif defined(HAVE_MEMSET_S)
+ /* This is in the C99 standard. */
+ memset_s(mem, sz, 0, sz);
+#else
+ /* This is a slow and ugly function from OpenSSL that fills 'mem' with junk
+ * based on the pointer value, then uses that junk to update a global
+ * variable. It's an elaborate ruse to trick the compiler into not
+ * optimizing out the "wipe this memory" code. Read it if you like zany
+ * programming tricks! In later versions of Tor, we should look for better
+ * not-optimized-out memory wiping stuff...
+ *
+ * ...or maybe not. In practice, there are pure-asm implementations of
+ * OPENSSL_cleanse() on most platforms, which ought to do the job.
+ **/
+
+ OPENSSL_cleanse(mem, sz);
+#endif /* defined(SecureZeroMemory) || defined(HAVE_SECUREZEROMEMORY) || ... */
+
+ /* Just in case some caller of memwipe() is relying on getting a buffer
+ * filled with a particular value, fill the buffer.
+ *
+ * If this function gets inlined, this memset might get eliminated, but
+ * that's okay: We only care about this particular memset in the case where
+ * the caller should have been using memset(), and the memset() wouldn't get
+ * eliminated. In other words, this is here so that we won't break anything
+ * if somebody accidentally calls memwipe() instead of memset().
+ **/
+ memset(mem, byte, sz);
+}
+
+#endif /* !defined(CRYPTO_UTIL_PRIVATE) */
+
diff --git a/src/common/crypto_util.h b/src/common/crypto_util.h
new file mode 100644
index 0000000000..922942b371
--- /dev/null
+++ b/src/common/crypto_util.h
@@ -0,0 +1,27 @@
+/* Copyright (c) 2001, Matej Pfajfar.
+ * Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
+ * Copyright (c) 2007-2018, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file crypto_util.h
+ *
+ * \brief Common functions for cryptographic routines.
+ **/
+
+#ifndef TOR_CRYPTO_UTIL_H
+#define TOR_CRYPTO_UTIL_H
+
+#include "torint.h"
+
+/** OpenSSL-based utility functions. */
+void memwipe(void *mem, uint8_t byte, size_t sz);
+
+#ifdef CRYPTO_UTIL_PRIVATE
+#ifdef TOR_UNIT_TESTS
+#endif /* defined(TOR_UNIT_TESTS) */
+#endif /* defined(CRYPTO_UTIL_PRIVATE) */
+
+#endif /* !defined(TOR_CRYPTO_UTIL_H) */
+
diff --git a/src/common/include.am b/src/common/include.am
index 87ab9d79e9..bce3fa20f6 100644
--- a/src/common/include.am
+++ b/src/common/include.am
@@ -116,11 +116,13 @@ LIBOR_CRYPTO_A_SRC = \
src/common/compress_zstd.c \
src/common/crypto.c \
src/common/crypto_digest.c \
- src/common/crypto_rsa.c \
+ src/common/crypto_format.c \
src/common/crypto_openssl_mgt.c \
src/common/crypto_pwbox.c \
+ src/common/crypto_rand.c \
+ src/common/crypto_rsa.c \
src/common/crypto_s2k.c \
- src/common/crypto_format.c \
+ src/common/crypto_util.c \
src/common/tortls.c \
src/common/crypto_curve25519.c \
src/common/crypto_ed25519.c
@@ -172,9 +174,11 @@ COMMONHEADERS = \
src/common/crypto_ed25519.h \
src/common/crypto_format.h \
src/common/crypto_openssl_mgt.h \
- src/common/crypto_rsa.h \
src/common/crypto_pwbox.h \
+ src/common/crypto_rand.h \
+ src/common/crypto_rsa.h \
src/common/crypto_s2k.h \
+ src/common/crypto_util.h \
src/common/di_ops.h \
src/common/handles.h \
src/common/memarea.h \
diff --git a/src/common/log.c b/src/common/log.c
index 922e9dd38f..ebd50f62d3 100644
--- a/src/common/log.c
+++ b/src/common/log.c
@@ -170,6 +170,9 @@ typedef struct pending_log_message_t {
/** Log messages waiting to be replayed onto callback-based logs */
static smartlist_t *pending_cb_messages = NULL;
+/** Callback to invoke when pending_cb_messages becomes nonempty. */
+static pending_callback_callback pending_cb_cb = NULL;
+
/** Log messages waiting to be replayed once the logging system is initialized.
*/
static smartlist_t *pending_startup_messages = NULL;
@@ -538,6 +541,9 @@ logfile_deliver(logfile_t *lf, const char *buf, size_t msg_len,
smartlist_add(pending_cb_messages,
pending_log_message_new(severity,domain,NULL,msg_after_prefix));
*callbacks_deferred = 1;
+ if (smartlist_len(pending_cb_messages) == 1 && pending_cb_cb) {
+ pending_cb_cb();
+ }
}
} else {
lf->callback(severity, domain, msg_after_prefix);
@@ -825,6 +831,7 @@ logs_free_all(void)
logfiles = NULL;
messages = pending_cb_messages;
pending_cb_messages = NULL;
+ pending_cb_cb = NULL;
messages2 = pending_startup_messages;
pending_startup_messages = NULL;
UNLOCK_LOGS();
@@ -988,6 +995,24 @@ add_temp_log(int min_severity)
}
/**
+ * Register "cb" as the callback to call when there are new pending log
+ * callbacks to be flushed with flush_pending_log_callbacks().
+ *
+ * Note that this callback, if present, can be invoked from any thread.
+ *
+ * This callback must not log.
+ *
+ * It is intentional that this function contains the name "callback" twice: it
+ * sets a "callback" to be called on the condition that there is a "pending
+ * callback".
+ **/
+void
+logs_set_pending_callback_callback(pending_callback_callback cb)
+{
+ pending_cb_cb = cb;
+}
+
+/**
* Add a log handler to send messages in <b>severity</b>
* to the function <b>cb</b>.
*/
diff --git a/src/common/sandbox.c b/src/common/sandbox.c
index 3588f60dec..440f8722f2 100644
--- a/src/common/sandbox.c
+++ b/src/common/sandbox.c
@@ -197,6 +197,9 @@ static int filter_nopar_gen[] = {
SCMP_SYS(mmap),
#endif
SCMP_SYS(munmap),
+#ifdef __NR_nanosleep
+ SCMP_SYS(nanosleep),
+#endif
#ifdef __NR_prlimit
SCMP_SYS(prlimit),
#endif
diff --git a/src/common/token_bucket.c b/src/common/token_bucket.c
index 747189e751..f2396ec58a 100644
--- a/src/common/token_bucket.c
+++ b/src/common/token_bucket.c
@@ -238,13 +238,18 @@ token_bucket_rw_dec_write(token_bucket_rw_t *bucket,
/**
* As token_bucket_rw_dec_read and token_bucket_rw_dec_write, in a single
- * operation.
+ * operation. Return a bitmask of TB_READ and TB_WRITE to indicate
+ * which buckets became empty.
*/
-void
+int
token_bucket_rw_dec(token_bucket_rw_t *bucket,
ssize_t n_read, ssize_t n_written)
{
- token_bucket_rw_dec_read(bucket, n_read);
- token_bucket_rw_dec_write(bucket, n_written);
+ int flags = 0;
+ if (token_bucket_rw_dec_read(bucket, n_read))
+ flags |= TB_READ;
+ if (token_bucket_rw_dec_write(bucket, n_written))
+ flags |= TB_WRITE;
+ return flags;
}
diff --git a/src/common/token_bucket.h b/src/common/token_bucket.h
index fb5d9fc60a..0e7832e838 100644
--- a/src/common/token_bucket.h
+++ b/src/common/token_bucket.h
@@ -85,8 +85,8 @@ int token_bucket_rw_dec_read(token_bucket_rw_t *bucket,
int token_bucket_rw_dec_write(token_bucket_rw_t *bucket,
ssize_t n);
-void token_bucket_rw_dec(token_bucket_rw_t *bucket,
- ssize_t n_read, ssize_t n_written);
+int token_bucket_rw_dec(token_bucket_rw_t *bucket,
+ ssize_t n_read, ssize_t n_written);
static inline size_t token_bucket_rw_get_read(const token_bucket_rw_t *bucket);
static inline size_t
diff --git a/src/common/torint.h b/src/common/torint.h
index 0b8061d24f..fc7818fe2c 100644
--- a/src/common/torint.h
+++ b/src/common/torint.h
@@ -40,6 +40,8 @@
#include <inttypes.h>
#endif
+#include <stdbool.h>
+
#if (SIZEOF_INT8_T != 0)
#define HAVE_INT8_T
#endif
diff --git a/src/common/torlog.h b/src/common/torlog.h
index ac632ff521..de389883c0 100644
--- a/src/common/torlog.h
+++ b/src/common/torlog.h
@@ -154,6 +154,8 @@ int add_android_log(const log_severity_list_t *severity,
const char *android_identity_tag);
#endif // HAVE_ANDROID_LOG_H.
int add_callback_log(const log_severity_list_t *severity, log_callback cb);
+typedef void (*pending_callback_callback)(void);
+void logs_set_pending_callback_callback(pending_callback_callback cb);
void logs_set_domain_logging(int enabled);
int get_min_log_level(void);
void switch_logs_debug(void);
diff --git a/src/common/tortls.c b/src/common/tortls.c
index 05e29e22ff..10b0319bec 100644
--- a/src/common/tortls.c
+++ b/src/common/tortls.c
@@ -26,6 +26,8 @@
#endif
#include "crypto.h"
+#include "crypto_rand.h"
+#include "crypto_util.h"
#include "compat.h"
/* Some versions of OpenSSL declare SSL_get_selected_srtp_profile twice in
@@ -56,10 +58,25 @@ ENABLE_GCC_WARNING(redundant-decls)
#include "container.h"
#include <string.h>
+#if OPENSSL_VERSION_NUMBER >= OPENSSL_V_SERIES(1,1,0)
+#define X509_get_notBefore_const(cert) \
+ X509_get0_notBefore(cert)
+#define X509_get_notAfter_const(cert) \
+ X509_get0_notAfter(cert)
+#ifndef X509_get_notBefore
+#define X509_get_notBefore(cert) \
+ X509_getm_notBefore(cert)
+#endif
+#ifndef X509_get_notAfter
+#define X509_get_notAfter(cert) \
+ X509_getm_notAfter(cert)
+#endif
+#else /* ! OPENSSL_VERSION_NUMBER >= OPENSSL_V_SERIES(1,1,0) */
#define X509_get_notBefore_const(cert) \
((const ASN1_TIME*) X509_get_notBefore((X509 *)cert))
#define X509_get_notAfter_const(cert) \
((const ASN1_TIME*) X509_get_notAfter((X509 *)cert))
+#endif
/* Copied from or.h */
#define LEGAL_NICKNAME_CHARACTERS \
@@ -355,8 +372,12 @@ tor_tls_init(void)
check_no_tls_errors();
if (!tls_library_is_initialized) {
+#if OPENSSL_VERSION_NUMBER >= OPENSSL_V_SERIES(1,1,0)
+ OPENSSL_init_ssl(OPENSSL_INIT_LOAD_SSL_STRINGS, NULL);
+#else
SSL_library_init();
SSL_load_error_strings();
+#endif
#if (SIZEOF_VOID_P >= 8 && \
OPENSSL_VERSION_NUMBER >= OPENSSL_V_SERIES(1,0,1))
diff --git a/src/common/util.c b/src/common/util.c
index 041e7aee3d..53e4507f1f 100644
--- a/src/common/util.c
+++ b/src/common/util.c
@@ -572,6 +572,19 @@ add_laplace_noise(int64_t signal_, double random_, double delta_f,
return signal_ + noise;
}
+/* Helper: safely add two uint32_t's, capping at UINT32_MAX rather
+ * than overflow */
+uint32_t
+tor_add_u32_nowrap(uint32_t a, uint32_t b)
+{
+ /* a+b > UINT32_MAX check, without overflow */
+ if (PREDICT_UNLIKELY(a > UINT32_MAX - b)) {
+ return UINT32_MAX;
+ } else {
+ return a+b;
+ }
+}
+
/* Helper: return greatest common divisor of a,b */
static uint64_t
gcd64(uint64_t a, uint64_t b)
@@ -1821,6 +1834,15 @@ format_iso_time(char *buf, time_t t)
strftime(buf, ISO_TIME_LEN+1, "%Y-%m-%d %H:%M:%S", tor_gmtime_r(&t, &tm));
}
+/** As format_local_iso_time, but use the yyyy-mm-ddThh:mm:ss format to avoid
+ * embedding an internal space. */
+void
+format_local_iso_time_nospace(char *buf, time_t t)
+{
+ format_local_iso_time(buf, t);
+ buf[10] = 'T';
+}
+
/** As format_iso_time, but use the yyyy-mm-ddThh:mm:ss format to avoid
* embedding an internal space. */
void
diff --git a/src/common/util.h b/src/common/util.h
index ae27e5f016..7172b7da08 100644
--- a/src/common/util.h
+++ b/src/common/util.h
@@ -176,6 +176,8 @@ int n_bits_set_u8(uint8_t v);
int64_t clamp_double_to_int64(double number);
void simplify_fraction64(uint64_t *numer, uint64_t *denom);
+uint32_t tor_add_u32_nowrap(uint32_t a, uint32_t b);
+
/* Compute the CEIL of <b>a</b> divided by <b>b</b>, for nonnegative <b>a</b>
* and positive <b>b</b>. Works on integer types only. Not defined if a+(b-1)
* can overflow. */
@@ -269,6 +271,7 @@ int parse_rfc1123_time(const char *buf, time_t *t);
#define ISO_TIME_USEC_LEN (ISO_TIME_LEN+7)
void format_local_iso_time(char *buf, time_t t);
void format_iso_time(char *buf, time_t t);
+void format_local_iso_time_nospace(char *buf, time_t t);
void format_iso_time_nospace(char *buf, time_t t);
void format_iso_time_nospace_usec(char *buf, const struct timeval *tv);
int parse_iso_time_(const char *cp, time_t *t, int strict, int nospace);
diff --git a/src/common/workqueue.c b/src/common/workqueue.c
index 12e31414e7..563a98af96 100644
--- a/src/common/workqueue.c
+++ b/src/common/workqueue.c
@@ -27,7 +27,7 @@
#include "compat.h"
#include "compat_libevent.h"
#include "compat_threads.h"
-#include "crypto.h"
+#include "crypto_rand.h"
#include "util.h"
#include "workqueue.h"
#include "tor_queue.h"