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-rw-r--r--src/common/crypto.c1407
1 files changed, 20 insertions, 1387 deletions
diff --git a/src/common/crypto.c b/src/common/crypto.c
index d85aca4004..d5b7c96916 100644
--- a/src/common/crypto.c
+++ b/src/common/crypto.c
@@ -23,25 +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_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)
@@ -59,18 +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"
@@ -83,12 +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 {
@@ -161,23 +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. */
@@ -203,8 +169,15 @@ crypto_early_init(void)
crypto_early_initialized_ = 1;
+#ifdef OPENSSL_1_1_API
+ 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();
@@ -397,266 +370,6 @@ crypto_cipher_free_(crypto_cipher_t *env)
aes_cipher_free(env);
}
-/* public key crypto */
-
-/** Check a siglen-byte long signature at <b>sig</b> against
- * <b>datalen</b> bytes of data at <b>data</b>, using the public key
- * in <b>env</b>. Return 0 if <b>sig</b> is a correct signature for
- * SHA1(data). Else return -1.
- */
-MOCK_IMPL(int,
-crypto_pk_public_checksig_digest,(crypto_pk_t *env, const char *data,
- size_t datalen, const char *sig,
- size_t siglen))
-{
- char digest[DIGEST_LEN];
- char *buf;
- size_t buflen;
- int r;
-
- tor_assert(env);
- tor_assert(data);
- tor_assert(sig);
- tor_assert(datalen < SIZE_T_CEILING);
- tor_assert(siglen < SIZE_T_CEILING);
-
- if (crypto_digest(digest,data,datalen)<0) {
- log_warn(LD_BUG, "couldn't compute digest");
- return -1;
- }
- buflen = crypto_pk_keysize(env);
- buf = tor_malloc(buflen);
- r = crypto_pk_public_checksig(env,buf,buflen,sig,siglen);
- if (r != DIGEST_LEN) {
- log_warn(LD_CRYPTO, "Invalid signature");
- tor_free(buf);
- return -1;
- }
- if (tor_memneq(buf, digest, DIGEST_LEN)) {
- log_warn(LD_CRYPTO, "Signature mismatched with digest.");
- tor_free(buf);
- return -1;
- }
- tor_free(buf);
-
- return 0;
-}
-
-/** Compute a SHA1 digest of <b>fromlen</b> bytes of data stored at
- * <b>from</b>; sign the data with the private key in <b>env</b>, and
- * store it in <b>to</b>. Return the number of bytes written on
- * success, and -1 on failure.
- *
- * <b>tolen</b> is the number of writable bytes in <b>to</b>, and must be
- * at least the length of the modulus of <b>env</b>.
- */
-int
-crypto_pk_private_sign_digest(crypto_pk_t *env, char *to, size_t tolen,
- const char *from, size_t fromlen)
-{
- int r;
- char digest[DIGEST_LEN];
- if (crypto_digest(digest,from,fromlen)<0)
- return -1;
- r = crypto_pk_private_sign(env,to,tolen,digest,DIGEST_LEN);
- memwipe(digest, 0, sizeof(digest));
- return r;
-}
-
-/** Perform a hybrid (public/secret) encryption on <b>fromlen</b>
- * bytes of data from <b>from</b>, with padding type 'padding',
- * storing the results on <b>to</b>.
- *
- * Returns the number of bytes written on success, -1 on failure.
- *
- * The encrypted data consists of:
- * - The source data, padded and encrypted with the public key, if the
- * padded source data is no longer than the public key, and <b>force</b>
- * is false, OR
- * - The beginning of the source data prefixed with a 16-byte symmetric key,
- * padded and encrypted with the public key; followed by the rest of
- * the source data encrypted in AES-CTR mode with the symmetric key.
- *
- * NOTE that this format does not authenticate the symmetrically encrypted
- * part of the data, and SHOULD NOT BE USED for new protocols.
- */
-int
-crypto_pk_obsolete_public_hybrid_encrypt(crypto_pk_t *env,
- char *to, size_t tolen,
- const char *from,
- size_t fromlen,
- int padding, int force)
-{
- int overhead, outlen, r;
- size_t pkeylen, symlen;
- crypto_cipher_t *cipher = NULL;
- char *buf = NULL;
-
- tor_assert(env);
- tor_assert(from);
- tor_assert(to);
- tor_assert(fromlen < SIZE_T_CEILING);
-
- overhead = crypto_get_rsa_padding_overhead(crypto_get_rsa_padding(padding));
- pkeylen = crypto_pk_keysize(env);
-
- if (!force && fromlen+overhead <= pkeylen) {
- /* It all fits in a single encrypt. */
- return crypto_pk_public_encrypt(env,to,
- tolen,
- from,fromlen,padding);
- }
- tor_assert(tolen >= fromlen + overhead + CIPHER_KEY_LEN);
- tor_assert(tolen >= pkeylen);
-
- char key[CIPHER_KEY_LEN];
- crypto_rand(key, sizeof(key)); /* generate a new key. */
- cipher = crypto_cipher_new(key);
-
- buf = tor_malloc(pkeylen+1);
- memcpy(buf, key, CIPHER_KEY_LEN);
- memcpy(buf+CIPHER_KEY_LEN, from, pkeylen-overhead-CIPHER_KEY_LEN);
-
- /* Length of symmetrically encrypted data. */
- symlen = fromlen-(pkeylen-overhead-CIPHER_KEY_LEN);
-
- outlen = crypto_pk_public_encrypt(env,to,tolen,buf,pkeylen-overhead,padding);
- if (outlen!=(int)pkeylen) {
- goto err;
- }
- r = crypto_cipher_encrypt(cipher, to+outlen,
- from+pkeylen-overhead-CIPHER_KEY_LEN, symlen);
-
- if (r<0) goto err;
- memwipe(buf, 0, pkeylen);
- memwipe(key, 0, sizeof(key));
- tor_free(buf);
- crypto_cipher_free(cipher);
- tor_assert(outlen+symlen < INT_MAX);
- return (int)(outlen + symlen);
- err:
-
- memwipe(buf, 0, pkeylen);
- memwipe(key, 0, sizeof(key));
- tor_free(buf);
- crypto_cipher_free(cipher);
- return -1;
-}
-
-/** Invert crypto_pk_obsolete_public_hybrid_encrypt. Returns the number of
- * bytes written on success, -1 on failure.
- *
- * NOTE that this format does not authenticate the symmetrically encrypted
- * part of the data, and SHOULD NOT BE USED for new protocols.
- */
-int
-crypto_pk_obsolete_private_hybrid_decrypt(crypto_pk_t *env,
- char *to,
- size_t tolen,
- const char *from,
- size_t fromlen,
- int padding, int warnOnFailure)
-{
- int outlen, r;
- size_t pkeylen;
- crypto_cipher_t *cipher = NULL;
- char *buf = NULL;
-
- tor_assert(fromlen < SIZE_T_CEILING);
- pkeylen = crypto_pk_keysize(env);
-
- if (fromlen <= pkeylen) {
- return crypto_pk_private_decrypt(env,to,tolen,from,fromlen,padding,
- warnOnFailure);
- }
-
- buf = tor_malloc(pkeylen);
- outlen = crypto_pk_private_decrypt(env,buf,pkeylen,from,pkeylen,padding,
- warnOnFailure);
- if (outlen<0) {
- log_fn(warnOnFailure?LOG_WARN:LOG_DEBUG, LD_CRYPTO,
- "Error decrypting public-key data");
- goto err;
- }
- if (outlen < CIPHER_KEY_LEN) {
- log_fn(warnOnFailure?LOG_WARN:LOG_INFO, LD_CRYPTO,
- "No room for a symmetric key");
- goto err;
- }
- cipher = crypto_cipher_new(buf);
- if (!cipher) {
- goto err;
- }
- memcpy(to,buf+CIPHER_KEY_LEN,outlen-CIPHER_KEY_LEN);
- outlen -= CIPHER_KEY_LEN;
- tor_assert(tolen - outlen >= fromlen - pkeylen);
- r = crypto_cipher_decrypt(cipher, to+outlen, from+pkeylen, fromlen-pkeylen);
- if (r<0)
- goto err;
- memwipe(buf,0,pkeylen);
- tor_free(buf);
- crypto_cipher_free(cipher);
- tor_assert(outlen + fromlen < INT_MAX);
- return (int)(outlen + (fromlen-pkeylen));
- err:
- memwipe(buf,0,pkeylen);
- tor_free(buf);
- crypto_cipher_free(cipher);
- return -1;
-}
-
-/** Given a private or public key <b>pk</b>, put a SHA1 hash of the
- * public key into <b>digest_out</b> (must have DIGEST_LEN bytes of space).
- * Return 0 on success, -1 on failure.
- */
-int
-crypto_pk_get_digest(const crypto_pk_t *pk, char *digest_out)
-{
- char *buf;
- size_t buflen;
- int len;
- int rv = -1;
-
- buflen = crypto_pk_keysize(pk)*2;
- buf = tor_malloc(buflen);
- len = crypto_pk_asn1_encode(pk, buf, buflen);
- if (len < 0)
- goto done;
-
- if (crypto_digest(digest_out, buf, len) < 0)
- goto done;
-
- rv = 0;
- done:
- tor_free(buf);
- return rv;
-}
-
-/** Compute all digests of the DER encoding of <b>pk</b>, and store them
- * in <b>digests_out</b>. Return 0 on success, -1 on failure. */
-int
-crypto_pk_get_common_digests(crypto_pk_t *pk, common_digests_t *digests_out)
-{
- char *buf;
- size_t buflen;
- int len;
- int rv = -1;
-
- buflen = crypto_pk_keysize(pk)*2;
- buf = tor_malloc(buflen);
- len = crypto_pk_asn1_encode(pk, buf, buflen);
- if (len < 0)
- goto done;
-
- if (crypto_common_digests(digests_out, (char*)buf, len) < 0)
- goto done;
-
- rv = 0;
- done:
- tor_free(buf);
- return rv;
-}
-
/** Copy <b>in</b> to the <b>outlen</b>-byte buffer <b>out</b>, adding spaces
* every four characters. */
void
@@ -788,524 +501,6 @@ crypto_cipher_decrypt_with_iv(const char *key,
return (int)(fromlen - CIPHER_IV_LEN);
}
-/* SHA-1 */
-
-/** Compute the SHA1 digest of the <b>len</b> bytes on data stored in
- * <b>m</b>. Write the DIGEST_LEN byte result into <b>digest</b>.
- * Return 0 on success, -1 on failure.
- */
-int
-crypto_digest(char *digest, const char *m, size_t len)
-{
- tor_assert(m);
- tor_assert(digest);
- if (SHA1((const unsigned char*)m,len,(unsigned char*)digest) == NULL)
- return -1;
- return 0;
-}
-
-/** Compute a 256-bit digest of <b>len</b> bytes in data stored in <b>m</b>,
- * using the algorithm <b>algorithm</b>. Write the DIGEST_LEN256-byte result
- * into <b>digest</b>. Return 0 on success, -1 on failure. */
-int
-crypto_digest256(char *digest, const char *m, size_t len,
- digest_algorithm_t algorithm)
-{
- tor_assert(m);
- tor_assert(digest);
- tor_assert(algorithm == DIGEST_SHA256 || algorithm == DIGEST_SHA3_256);
-
- int ret = 0;
- if (algorithm == DIGEST_SHA256)
- ret = (SHA256((const uint8_t*)m,len,(uint8_t*)digest) != NULL);
- else
- ret = (sha3_256((uint8_t *)digest, DIGEST256_LEN,(const uint8_t *)m, len)
- > -1);
-
- if (!ret)
- return -1;
- return 0;
-}
-
-/** Compute a 512-bit digest of <b>len</b> bytes in data stored in <b>m</b>,
- * using the algorithm <b>algorithm</b>. Write the DIGEST_LEN512-byte result
- * into <b>digest</b>. Return 0 on success, -1 on failure. */
-int
-crypto_digest512(char *digest, const char *m, size_t len,
- digest_algorithm_t algorithm)
-{
- tor_assert(m);
- tor_assert(digest);
- tor_assert(algorithm == DIGEST_SHA512 || algorithm == DIGEST_SHA3_512);
-
- int ret = 0;
- if (algorithm == DIGEST_SHA512)
- ret = (SHA512((const unsigned char*)m,len,(unsigned char*)digest)
- != NULL);
- else
- ret = (sha3_512((uint8_t*)digest, DIGEST512_LEN, (const uint8_t*)m, len)
- > -1);
-
- if (!ret)
- return -1;
- return 0;
-}
-
-/** Set the common_digests_t in <b>ds_out</b> to contain every digest on the
- * <b>len</b> bytes in <b>m</b> that we know how to compute. Return 0 on
- * success, -1 on failure. */
-int
-crypto_common_digests(common_digests_t *ds_out, const char *m, size_t len)
-{
- tor_assert(ds_out);
- memset(ds_out, 0, sizeof(*ds_out));
- if (crypto_digest(ds_out->d[DIGEST_SHA1], m, len) < 0)
- return -1;
- if (crypto_digest256(ds_out->d[DIGEST_SHA256], m, len, DIGEST_SHA256) < 0)
- return -1;
-
- return 0;
-}
-
-/** Return the name of an algorithm, as used in directory documents. */
-const char *
-crypto_digest_algorithm_get_name(digest_algorithm_t alg)
-{
- switch (alg) {
- case DIGEST_SHA1:
- return "sha1";
- case DIGEST_SHA256:
- return "sha256";
- case DIGEST_SHA512:
- return "sha512";
- case DIGEST_SHA3_256:
- return "sha3-256";
- case DIGEST_SHA3_512:
- return "sha3-512";
- // LCOV_EXCL_START
- default:
- tor_fragile_assert();
- return "??unknown_digest??";
- // LCOV_EXCL_STOP
- }
-}
-
-/** Given the name of a digest algorithm, return its integer value, or -1 if
- * the name is not recognized. */
-int
-crypto_digest_algorithm_parse_name(const char *name)
-{
- if (!strcmp(name, "sha1"))
- return DIGEST_SHA1;
- else if (!strcmp(name, "sha256"))
- return DIGEST_SHA256;
- else if (!strcmp(name, "sha512"))
- return DIGEST_SHA512;
- else if (!strcmp(name, "sha3-256"))
- return DIGEST_SHA3_256;
- else if (!strcmp(name, "sha3-512"))
- return DIGEST_SHA3_512;
- else
- return -1;
-}
-
-/** Given an algorithm, return the digest length in bytes. */
-size_t
-crypto_digest_algorithm_get_length(digest_algorithm_t alg)
-{
- switch (alg) {
- case DIGEST_SHA1:
- return DIGEST_LEN;
- case DIGEST_SHA256:
- return DIGEST256_LEN;
- case DIGEST_SHA512:
- return DIGEST512_LEN;
- case DIGEST_SHA3_256:
- return DIGEST256_LEN;
- case DIGEST_SHA3_512:
- return DIGEST512_LEN;
- default:
- tor_assert(0); // LCOV_EXCL_LINE
- return 0; /* Unreachable */ // LCOV_EXCL_LINE
- }
-}
-
-/** Intermediate information about the digest of a stream of data. */
-struct crypto_digest_t {
- digest_algorithm_t algorithm; /**< Which algorithm is in use? */
- /** State for the digest we're using. Only one member of the
- * union is usable, depending on the value of <b>algorithm</b>. Note also
- * that space for other members might not even be allocated!
- */
- union {
- SHA_CTX sha1; /**< state for SHA1 */
- SHA256_CTX sha2; /**< state for SHA256 */
- SHA512_CTX sha512; /**< state for SHA512 */
- keccak_state sha3; /**< state for SHA3-[256,512] */
- } d;
-};
-
-#ifdef TOR_UNIT_TESTS
-
-digest_algorithm_t
-crypto_digest_get_algorithm(crypto_digest_t *digest)
-{
- tor_assert(digest);
-
- return digest->algorithm;
-}
-
-#endif /* defined(TOR_UNIT_TESTS) */
-
-/**
- * Return the number of bytes we need to malloc in order to get a
- * crypto_digest_t for <b>alg</b>, or the number of bytes we need to wipe
- * when we free one.
- */
-static size_t
-crypto_digest_alloc_bytes(digest_algorithm_t alg)
-{
- /* Helper: returns the number of bytes in the 'f' field of 'st' */
-#define STRUCT_FIELD_SIZE(st, f) (sizeof( ((st*)0)->f ))
- /* Gives the length of crypto_digest_t through the end of the field 'd' */
-#define END_OF_FIELD(f) (offsetof(crypto_digest_t, f) + \
- STRUCT_FIELD_SIZE(crypto_digest_t, f))
- switch (alg) {
- case DIGEST_SHA1:
- return END_OF_FIELD(d.sha1);
- case DIGEST_SHA256:
- return END_OF_FIELD(d.sha2);
- case DIGEST_SHA512:
- return END_OF_FIELD(d.sha512);
- case DIGEST_SHA3_256:
- case DIGEST_SHA3_512:
- return END_OF_FIELD(d.sha3);
- default:
- tor_assert(0); // LCOV_EXCL_LINE
- return 0; // LCOV_EXCL_LINE
- }
-#undef END_OF_FIELD
-#undef STRUCT_FIELD_SIZE
-}
-
-/**
- * Internal function: create and return a new digest object for 'algorithm'.
- * Does not typecheck the algorithm.
- */
-static crypto_digest_t *
-crypto_digest_new_internal(digest_algorithm_t algorithm)
-{
- crypto_digest_t *r = tor_malloc(crypto_digest_alloc_bytes(algorithm));
- r->algorithm = algorithm;
-
- switch (algorithm)
- {
- case DIGEST_SHA1:
- SHA1_Init(&r->d.sha1);
- break;
- case DIGEST_SHA256:
- SHA256_Init(&r->d.sha2);
- break;
- case DIGEST_SHA512:
- SHA512_Init(&r->d.sha512);
- break;
- case DIGEST_SHA3_256:
- keccak_digest_init(&r->d.sha3, 256);
- break;
- case DIGEST_SHA3_512:
- keccak_digest_init(&r->d.sha3, 512);
- break;
- default:
- tor_assert_unreached();
- }
-
- return r;
-}
-
-/** Allocate and return a new digest object to compute SHA1 digests.
- */
-crypto_digest_t *
-crypto_digest_new(void)
-{
- return crypto_digest_new_internal(DIGEST_SHA1);
-}
-
-/** Allocate and return a new digest object to compute 256-bit digests
- * using <b>algorithm</b>. */
-crypto_digest_t *
-crypto_digest256_new(digest_algorithm_t algorithm)
-{
- tor_assert(algorithm == DIGEST_SHA256 || algorithm == DIGEST_SHA3_256);
- return crypto_digest_new_internal(algorithm);
-}
-
-/** Allocate and return a new digest object to compute 512-bit digests
- * using <b>algorithm</b>. */
-crypto_digest_t *
-crypto_digest512_new(digest_algorithm_t algorithm)
-{
- tor_assert(algorithm == DIGEST_SHA512 || algorithm == DIGEST_SHA3_512);
- return crypto_digest_new_internal(algorithm);
-}
-
-/** Deallocate a digest object.
- */
-void
-crypto_digest_free_(crypto_digest_t *digest)
-{
- if (!digest)
- return;
- size_t bytes = crypto_digest_alloc_bytes(digest->algorithm);
- memwipe(digest, 0, bytes);
- tor_free(digest);
-}
-
-/** Add <b>len</b> bytes from <b>data</b> to the digest object.
- */
-void
-crypto_digest_add_bytes(crypto_digest_t *digest, const char *data,
- size_t len)
-{
- tor_assert(digest);
- tor_assert(data);
- /* Using the SHA*_*() calls directly means we don't support doing
- * SHA in hardware. But so far the delay of getting the question
- * to the hardware, and hearing the answer, is likely higher than
- * just doing it ourselves. Hashes are fast.
- */
- switch (digest->algorithm) {
- case DIGEST_SHA1:
- SHA1_Update(&digest->d.sha1, (void*)data, len);
- break;
- case DIGEST_SHA256:
- SHA256_Update(&digest->d.sha2, (void*)data, len);
- break;
- case DIGEST_SHA512:
- SHA512_Update(&digest->d.sha512, (void*)data, len);
- break;
- case DIGEST_SHA3_256: /* FALLSTHROUGH */
- case DIGEST_SHA3_512:
- keccak_digest_update(&digest->d.sha3, (const uint8_t *)data, len);
- break;
- default:
- /* LCOV_EXCL_START */
- tor_fragile_assert();
- break;
- /* LCOV_EXCL_STOP */
- }
-}
-
-/** Compute the hash of the data that has been passed to the digest
- * object; write the first out_len bytes of the result to <b>out</b>.
- * <b>out_len</b> must be \<= DIGEST512_LEN.
- */
-void
-crypto_digest_get_digest(crypto_digest_t *digest,
- char *out, size_t out_len)
-{
- unsigned char r[DIGEST512_LEN];
- crypto_digest_t tmpenv;
- tor_assert(digest);
- tor_assert(out);
- tor_assert(out_len <= crypto_digest_algorithm_get_length(digest->algorithm));
-
- /* The SHA-3 code handles copying into a temporary ctx, and also can handle
- * short output buffers by truncating appropriately. */
- if (digest->algorithm == DIGEST_SHA3_256 ||
- digest->algorithm == DIGEST_SHA3_512) {
- keccak_digest_sum(&digest->d.sha3, (uint8_t *)out, out_len);
- return;
- }
-
- const size_t alloc_bytes = crypto_digest_alloc_bytes(digest->algorithm);
- /* memcpy into a temporary ctx, since SHA*_Final clears the context */
- memcpy(&tmpenv, digest, alloc_bytes);
- switch (digest->algorithm) {
- case DIGEST_SHA1:
- SHA1_Final(r, &tmpenv.d.sha1);
- break;
- case DIGEST_SHA256:
- SHA256_Final(r, &tmpenv.d.sha2);
- break;
- case DIGEST_SHA512:
- SHA512_Final(r, &tmpenv.d.sha512);
- break;
-//LCOV_EXCL_START
- case DIGEST_SHA3_256: /* FALLSTHROUGH */
- case DIGEST_SHA3_512:
- default:
- log_warn(LD_BUG, "Handling unexpected algorithm %d", digest->algorithm);
- /* This is fatal, because it should never happen. */
- tor_assert_unreached();
- break;
-//LCOV_EXCL_STOP
- }
- memcpy(out, r, out_len);
- memwipe(r, 0, sizeof(r));
-}
-
-/** Allocate and return a new digest object with the same state as
- * <b>digest</b>
- */
-crypto_digest_t *
-crypto_digest_dup(const crypto_digest_t *digest)
-{
- tor_assert(digest);
- const size_t alloc_bytes = crypto_digest_alloc_bytes(digest->algorithm);
- return tor_memdup(digest, alloc_bytes);
-}
-
-/** Replace the state of the digest object <b>into</b> with the state
- * of the digest object <b>from</b>. Requires that 'into' and 'from'
- * have the same digest type.
- */
-void
-crypto_digest_assign(crypto_digest_t *into,
- const crypto_digest_t *from)
-{
- tor_assert(into);
- tor_assert(from);
- tor_assert(into->algorithm == from->algorithm);
- const size_t alloc_bytes = crypto_digest_alloc_bytes(from->algorithm);
- memcpy(into,from,alloc_bytes);
-}
-
-/** Given a list of strings in <b>lst</b>, set the <b>len_out</b>-byte digest
- * at <b>digest_out</b> to the hash of the concatenation of those strings,
- * plus the optional string <b>append</b>, computed with the algorithm
- * <b>alg</b>.
- * <b>out_len</b> must be \<= DIGEST512_LEN. */
-void
-crypto_digest_smartlist(char *digest_out, size_t len_out,
- const smartlist_t *lst,
- const char *append,
- digest_algorithm_t alg)
-{
- crypto_digest_smartlist_prefix(digest_out, len_out, NULL, lst, append, alg);
-}
-
-/** Given a list of strings in <b>lst</b>, set the <b>len_out</b>-byte digest
- * at <b>digest_out</b> to the hash of the concatenation of: the
- * optional string <b>prepend</b>, those strings,
- * and the optional string <b>append</b>, computed with the algorithm
- * <b>alg</b>.
- * <b>len_out</b> must be \<= DIGEST512_LEN. */
-void
-crypto_digest_smartlist_prefix(char *digest_out, size_t len_out,
- const char *prepend,
- const smartlist_t *lst,
- const char *append,
- digest_algorithm_t alg)
-{
- crypto_digest_t *d = crypto_digest_new_internal(alg);
- if (prepend)
- crypto_digest_add_bytes(d, prepend, strlen(prepend));
- SMARTLIST_FOREACH(lst, const char *, cp,
- crypto_digest_add_bytes(d, cp, strlen(cp)));
- if (append)
- crypto_digest_add_bytes(d, append, strlen(append));
- crypto_digest_get_digest(d, digest_out, len_out);
- crypto_digest_free(d);
-}
-
-/** Compute the HMAC-SHA-256 of the <b>msg_len</b> bytes in <b>msg</b>, using
- * the <b>key</b> of length <b>key_len</b>. Store the DIGEST256_LEN-byte
- * result in <b>hmac_out</b>. Asserts on failure.
- */
-void
-crypto_hmac_sha256(char *hmac_out,
- const char *key, size_t key_len,
- const char *msg, size_t msg_len)
-{
- unsigned char *rv = NULL;
- /* If we've got OpenSSL >=0.9.8 we can use its hmac implementation. */
- tor_assert(key_len < INT_MAX);
- tor_assert(msg_len < INT_MAX);
- tor_assert(hmac_out);
- rv = HMAC(EVP_sha256(), key, (int)key_len, (unsigned char*)msg, (int)msg_len,
- (unsigned char*)hmac_out, NULL);
- tor_assert(rv);
-}
-
-/** Compute a MAC using SHA3-256 of <b>msg_len</b> bytes in <b>msg</b> using a
- * <b>key</b> of length <b>key_len</b> and a <b>salt</b> of length
- * <b>salt_len</b>. Store the result of <b>len_out</b> bytes in in
- * <b>mac_out</b>. This function can't fail. */
-void
-crypto_mac_sha3_256(uint8_t *mac_out, size_t len_out,
- const uint8_t *key, size_t key_len,
- const uint8_t *msg, size_t msg_len)
-{
- crypto_digest_t *digest;
-
- const uint64_t key_len_netorder = tor_htonll(key_len);
-
- tor_assert(mac_out);
- tor_assert(key);
- tor_assert(msg);
-
- digest = crypto_digest256_new(DIGEST_SHA3_256);
-
- /* Order matters here that is any subsystem using this function should
- * expect this very precise ordering in the MAC construction. */
- crypto_digest_add_bytes(digest, (const char *) &key_len_netorder,
- sizeof(key_len_netorder));
- crypto_digest_add_bytes(digest, (const char *) key, key_len);
- crypto_digest_add_bytes(digest, (const char *) msg, msg_len);
- crypto_digest_get_digest(digest, (char *) mac_out, len_out);
- crypto_digest_free(digest);
-}
-
-/** Internal state for a eXtendable-Output Function (XOF). */
-struct crypto_xof_t {
- keccak_state s;
-};
-
-/** Allocate a new XOF object backed by SHAKE-256. The security level
- * provided is a function of the length of the output used. Read and
- * understand FIPS-202 A.2 "Additional Consideration for Extendable-Output
- * Functions" before using this construct.
- */
-crypto_xof_t *
-crypto_xof_new(void)
-{
- crypto_xof_t *xof;
- xof = tor_malloc(sizeof(crypto_xof_t));
- keccak_xof_init(&xof->s, 256);
- return xof;
-}
-
-/** Absorb bytes into a XOF object. Must not be called after a call to
- * crypto_xof_squeeze_bytes() for the same instance, and will assert
- * if attempted.
- */
-void
-crypto_xof_add_bytes(crypto_xof_t *xof, const uint8_t *data, size_t len)
-{
- int i = keccak_xof_absorb(&xof->s, data, len);
- tor_assert(i == 0);
-}
-
-/** Squeeze bytes out of a XOF object. Calling this routine will render
- * the XOF instance ineligible to absorb further data.
- */
-void
-crypto_xof_squeeze_bytes(crypto_xof_t *xof, uint8_t *out, size_t len)
-{
- int i = keccak_xof_squeeze(&xof->s, out, len);
- tor_assert(i == 0);
-}
-
-/** Cleanse and deallocate a XOF object. */
-void
-crypto_xof_free_(crypto_xof_t *xof)
-{
- if (!xof)
- return;
- memwipe(xof, 0, sizeof(crypto_xof_t));
- tor_free(xof);
-}
-
/* DH */
/** Our DH 'g' parameter */
@@ -1860,576 +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.
@@ -2437,11 +1062,15 @@ memwipe(void *mem, uint8_t byte, size_t sz)
int
crypto_global_cleanup(void)
{
+#ifndef OPENSSL_1_1_API
EVP_cleanup();
+#endif
#ifndef NEW_THREAD_API
ERR_remove_thread_state(NULL);
#endif
+#ifndef OPENSSL_1_1_API
ERR_free_strings();
+#endif
if (dh_param_p)
BN_clear_free(dh_param_p);
@@ -2453,11 +1082,15 @@ crypto_global_cleanup(void)
dh_param_p = dh_param_p_tls = dh_param_g = NULL;
#ifndef DISABLE_ENGINES
+#ifndef OPENSSL_1_1_API
ENGINE_cleanup();
#endif
+#endif
CONF_modules_unload(1);
+#ifndef OPENSSL_1_1_API
CRYPTO_cleanup_all_ex_data();
+#endif
crypto_openssl_free_all();