commit 5d53862139ea3244735834d7a89077f53cd3df76 Author: rl1987 rl1987@sdf.lonestar.org Date: Fri Jan 18 12:26:13 2019 +0200
Split crypto_digest.c
* Move out code that depends on NSS to crypto_digest_nss.c * Move out code that depends on OpenSSL to crypto_digest_openssl.c * Keep the general code that is not specific to any of the above in crypto_digest.c --- changes/ticket29108 | 5 + src/lib/crypt_ops/crypto_digest.c | 736 ------------------------------ src/lib/crypt_ops/crypto_digest_nss.c | 560 +++++++++++++++++++++++ src/lib/crypt_ops/crypto_digest_openssl.c | 522 +++++++++++++++++++++ src/lib/crypt_ops/include.am | 2 + 5 files changed, 1089 insertions(+), 736 deletions(-)
diff --git a/changes/ticket29108 b/changes/ticket29108 new file mode 100644 index 000000000..7adb08ecb --- /dev/null +++ b/changes/ticket29108 @@ -0,0 +1,5 @@ + o Code simplification and refactoring: + - Split crypto_digest.c into three parts: 1) general code that does not + depend on either NSS or OpenSSL (stays in crypto_digest.c); 2) code that + depends on NSS API (moved to crypto_digest_nss.c); 3) code that depends + on OpenSSL API (moved to crypto_digest_openssl.c). Resolves ticket 29108. diff --git a/src/lib/crypt_ops/crypto_digest.c b/src/lib/crypt_ops/crypto_digest.c index 1e64100f2..9da135e9c 100644 --- a/src/lib/crypt_ops/crypto_digest.c +++ b/src/lib/crypt_ops/crypto_digest.c @@ -23,187 +23,6 @@
#include "lib/arch/bytes.h"
-#ifdef ENABLE_NSS -DISABLE_GCC_WARNING(strict-prototypes) -#include <pk11pub.h> -ENABLE_GCC_WARNING(strict-prototypes) -#else - -#include "lib/crypt_ops/crypto_openssl_mgt.h" - -DISABLE_GCC_WARNING(redundant-decls) - -#include <openssl/hmac.h> -#include <openssl/sha.h> - -ENABLE_GCC_WARNING(redundant-decls) - -#ifdef HAVE_EVP_SHA3_256 -#define OPENSSL_HAS_SHA3 -#include <openssl/evp.h> -#endif - -#endif - -#ifdef ENABLE_NSS -/** - * Convert a digest_algorithm_t (used by tor) to a HashType (used by NSS). - * On failure, return SEC_OID_UNKNOWN. */ -static SECOidTag -digest_alg_to_nss_oid(digest_algorithm_t alg) -{ - switch (alg) { - case DIGEST_SHA1: return SEC_OID_SHA1; - case DIGEST_SHA256: return SEC_OID_SHA256; - case DIGEST_SHA512: return SEC_OID_SHA512; - case DIGEST_SHA3_256: /* Fall through */ - case DIGEST_SHA3_512: /* Fall through */ - default: - return SEC_OID_UNKNOWN; - } -} - -/* Helper: get an unkeyed digest via pk11wrap */ -static int -digest_nss_internal(SECOidTag alg, - char *digest, unsigned len_out, - const char *msg, size_t msg_len) -{ - if (alg == SEC_OID_UNKNOWN) - return -1; - tor_assert(msg_len <= UINT_MAX); - - int rv = -1; - SECStatus s; - PK11Context *ctx = PK11_CreateDigestContext(alg); - if (!ctx) - return -1; - - s = PK11_DigestBegin(ctx); - if (s != SECSuccess) - goto done; - - s = PK11_DigestOp(ctx, (const unsigned char *)msg, (unsigned int)msg_len); - if (s != SECSuccess) - goto done; - - unsigned int len = 0; - s = PK11_DigestFinal(ctx, (unsigned char *)digest, &len, len_out); - if (s != SECSuccess) - goto done; - - rv = 0; - done: - PK11_DestroyContext(ctx, PR_TRUE); - return rv; -} - -/** True iff alg is implemented in our crypto library, and we want to use that - * implementation */ -static bool -library_supports_digest(digest_algorithm_t alg) -{ - switch (alg) { - case DIGEST_SHA1: /* Fall through */ - case DIGEST_SHA256: /* Fall through */ - case DIGEST_SHA512: /* Fall through */ - return true; - case DIGEST_SHA3_256: /* Fall through */ - case DIGEST_SHA3_512: /* Fall through */ - default: - return false; - } -} -#endif - -/* Crypto digest functions */ - -/** 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. - */ -MOCK_IMPL(int, -crypto_digest,(char *digest, const char *m, size_t len)) -{ - tor_assert(m); - tor_assert(digest); -#ifdef ENABLE_NSS - return digest_nss_internal(SEC_OID_SHA1, digest, DIGEST_LEN, m, len); -#else - if (SHA1((const unsigned char*)m,len,(unsigned char*)digest) == NULL) { - return -1; - } -#endif - 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) { -#ifdef ENABLE_NSS - return digest_nss_internal(SEC_OID_SHA256, digest, DIGEST256_LEN, m, len); -#else - ret = (SHA256((const uint8_t*)m,len,(uint8_t*)digest) != NULL); -#endif - } else { -#ifdef OPENSSL_HAS_SHA3 - unsigned int dlen = DIGEST256_LEN; - ret = EVP_Digest(m, len, (uint8_t*)digest, &dlen, EVP_sha3_256(), NULL); -#else - ret = (sha3_256((uint8_t *)digest, DIGEST256_LEN,(const uint8_t *)m, len) - > -1); -#endif - } - - 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) { -#ifdef ENABLE_NSS - return digest_nss_internal(SEC_OID_SHA512, digest, DIGEST512_LEN, m, len); -#else - ret = (SHA512((const unsigned char*)m,len,(unsigned char*)digest) - != NULL); -#endif - } else { -#ifdef OPENSSL_HAS_SHA3 - unsigned int dlen = DIGEST512_LEN; - ret = EVP_Digest(m, len, (uint8_t*)digest, &dlen, EVP_sha3_512(), NULL); -#else - ret = (sha3_512((uint8_t*)digest, DIGEST512_LEN, (const uint8_t*)m, len) - > -1); -#endif - } - - 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. */ @@ -283,561 +102,6 @@ crypto_digest_algorithm_get_length(digest_algorithm_t alg) } }
-/** 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 { -#ifdef ENABLE_NSS - PK11Context *ctx; -#else - SHA_CTX sha1; /**< state for SHA1 */ - SHA256_CTX sha2; /**< state for SHA256 */ - SHA512_CTX sha512; /**< state for SHA512 */ -#endif -#ifdef OPENSSL_HAS_SHA3 - EVP_MD_CTX *md; -#else - keccak_state sha3; /**< state for SHA3-[256,512] */ -#endif - } 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) { -#ifdef ENABLE_NSS - case DIGEST_SHA1: /* Fall through */ - case DIGEST_SHA256: /* Fall through */ - case DIGEST_SHA512: - return END_OF_FIELD(d.ctx); -#else - 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); -#endif -#ifdef OPENSSL_HAS_SHA3 - case DIGEST_SHA3_256: /* Fall through */ - case DIGEST_SHA3_512: - return END_OF_FIELD(d.md); -#else - case DIGEST_SHA3_256: /* Fall through */ - case DIGEST_SHA3_512: - return END_OF_FIELD(d.sha3); -#endif - 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) - { -#ifdef ENABLE_NSS - case DIGEST_SHA1: /* fall through */ - case DIGEST_SHA256: /* fall through */ - case DIGEST_SHA512: - r->d.ctx = PK11_CreateDigestContext(digest_alg_to_nss_oid(algorithm)); - if (BUG(!r->d.ctx)) { - tor_free(r); - return NULL; - } - if (BUG(SECSuccess != PK11_DigestBegin(r->d.ctx))) { - crypto_digest_free(r); - return NULL; - } - break; -#else - 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; -#endif -#ifdef OPENSSL_HAS_SHA3 - case DIGEST_SHA3_256: - r->d.md = EVP_MD_CTX_new(); - if (!EVP_DigestInit(r->d.md, EVP_sha3_256())) { - crypto_digest_free(r); - return NULL; - } - break; - case DIGEST_SHA3_512: - r->d.md = EVP_MD_CTX_new(); - if (!EVP_DigestInit(r->d.md, EVP_sha3_512())) { - crypto_digest_free(r); - return NULL; - } - break; -#else - case DIGEST_SHA3_256: - keccak_digest_init(&r->d.sha3, 256); - break; - case DIGEST_SHA3_512: - keccak_digest_init(&r->d.sha3, 512); - break; -#endif - 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>. - * - * C_RUST_COUPLED: `external::crypto_digest::crypto_digest256_new` - * C_RUST_COUPLED: `crypto::digest::Sha256::default` - */ -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; -#ifdef ENABLE_NSS - if (library_supports_digest(digest->algorithm)) { - PK11_DestroyContext(digest->d.ctx, PR_TRUE); - } -#endif -#ifdef OPENSSL_HAS_SHA3 - if (digest->algorithm == DIGEST_SHA3_256 || - digest->algorithm == DIGEST_SHA3_512) { - if (digest->d.md) { - EVP_MD_CTX_free(digest->d.md); - } - } -#endif - 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. - * - * C_RUST_COUPLED: `external::crypto_digest::crypto_digest_add_bytess` - * C_RUST_COUPLED: `crypto::digest::Sha256::process` - */ -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) { -#ifdef ENABLE_NSS - case DIGEST_SHA1: /* fall through */ - case DIGEST_SHA256: /* fall through */ - case DIGEST_SHA512: - tor_assert(len <= UINT_MAX); - SECStatus s = PK11_DigestOp(digest->d.ctx, - (const unsigned char *)data, - (unsigned int)len); - tor_assert(s == SECSuccess); - break; -#else - 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; -#endif -#ifdef OPENSSL_HAS_SHA3 - case DIGEST_SHA3_256: /* FALLSTHROUGH */ - case DIGEST_SHA3_512: { - int r = EVP_DigestUpdate(digest->d.md, data, len); - tor_assert(r); - } - break; -#else - case DIGEST_SHA3_256: /* FALLSTHROUGH */ - case DIGEST_SHA3_512: - keccak_digest_update(&digest->d.sha3, (const uint8_t *)data, len); - break; -#endif - 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. - * - * C_RUST_COUPLED: `external::crypto_digest::crypto_digest_get_digest` - * C_RUST_COUPLED: `impl digest::FixedOutput for Sha256` - */ -void -crypto_digest_get_digest(crypto_digest_t *digest, - char *out, size_t out_len) -{ - unsigned char r[DIGEST512_LEN]; - tor_assert(digest); - tor_assert(out); - tor_assert(out_len <= crypto_digest_algorithm_get_length(digest->algorithm)); - - if (digest->algorithm == DIGEST_SHA3_256 || - digest->algorithm == DIGEST_SHA3_512) { -#ifdef OPENSSL_HAS_SHA3 - unsigned dlen = (unsigned) - crypto_digest_algorithm_get_length(digest->algorithm); - EVP_MD_CTX *tmp = EVP_MD_CTX_new(); - EVP_MD_CTX_copy(tmp, digest->d.md); - memset(r, 0xff, sizeof(r)); - int res = EVP_DigestFinal(tmp, r, &dlen); - EVP_MD_CTX_free(tmp); - tor_assert(res == 1); - goto done; -#else - /* Tiny-Keccak handles copying into a temporary ctx, and also can handle - * short output buffers by truncating appropriately. */ - keccak_digest_sum(&digest->d.sha3, (uint8_t *)out, out_len); - return; -#endif - } - -#ifdef ENABLE_NSS - /* Copy into a temporary buffer since DigestFinal (alters) the context */ - unsigned char buf[1024]; - unsigned int saved_len = 0; - unsigned rlen; - unsigned char *saved = PK11_SaveContextAlloc(digest->d.ctx, - buf, sizeof(buf), - &saved_len); - tor_assert(saved); - SECStatus s = PK11_DigestFinal(digest->d.ctx, r, &rlen, sizeof(r)); - tor_assert(s == SECSuccess); - tor_assert(rlen >= out_len); - s = PK11_RestoreContext(digest->d.ctx, saved, saved_len); - tor_assert(s == SECSuccess); - if (saved != buf) { - PORT_ZFree(saved, saved_len); - } -#else - const size_t alloc_bytes = crypto_digest_alloc_bytes(digest->algorithm); - crypto_digest_t tmpenv; - /* 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 - } -#endif - -#ifdef OPENSSL_HAS_SHA3 - done: -#endif - 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> - * - * C_RUST_COUPLED: `external::crypto_digest::crypto_digest_dup` - * C_RUST_COUPLED: `impl Clone for crypto::digest::Sha256` - */ -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); - crypto_digest_t *result = tor_memdup(digest, alloc_bytes); -#ifdef ENABLE_NSS - if (library_supports_digest(digest->algorithm)) { - result->d.ctx = PK11_CloneContext(digest->d.ctx); - } -#endif -#ifdef OPENSSL_HAS_SHA3 - if (digest->algorithm == DIGEST_SHA3_256 || - digest->algorithm == DIGEST_SHA3_512) { - result->d.md = EVP_MD_CTX_new(); - EVP_MD_CTX_copy(result->d.md, digest->d.md); - } -#endif - return result; -} - -/** Temporarily save the state of <b>digest</b> in <b>checkpoint</b>. - * Asserts that <b>digest</b> is a SHA1 digest object. - */ -void -crypto_digest_checkpoint(crypto_digest_checkpoint_t *checkpoint, - const crypto_digest_t *digest) -{ - const size_t bytes = crypto_digest_alloc_bytes(digest->algorithm); - tor_assert(bytes <= sizeof(checkpoint->mem)); -#ifdef ENABLE_NSS - if (library_supports_digest(digest->algorithm)) { - unsigned char *allocated; - allocated = PK11_SaveContextAlloc(digest->d.ctx, - (unsigned char *)checkpoint->mem, - sizeof(checkpoint->mem), - &checkpoint->bytes_used); - /* No allocation is allowed here. */ - tor_assert(allocated == checkpoint->mem); - return; - } -#endif - memcpy(checkpoint->mem, digest, bytes); -} - -/** Restore the state of <b>digest</b> from <b>checkpoint</b>. - * Asserts that <b>digest</b> is a SHA1 digest object. Requires that the - * state was previously stored with crypto_digest_checkpoint() */ -void -crypto_digest_restore(crypto_digest_t *digest, - const crypto_digest_checkpoint_t *checkpoint) -{ - const size_t bytes = crypto_digest_alloc_bytes(digest->algorithm); -#ifdef ENABLE_NSS - if (library_supports_digest(digest->algorithm)) { - SECStatus s = PK11_RestoreContext(digest->d.ctx, - (unsigned char *)checkpoint->mem, - checkpoint->bytes_used); - tor_assert(s == SECSuccess); - return; - } -#endif - memcpy(digest, checkpoint->mem, 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); -#ifdef ENABLE_NSS - if (library_supports_digest(from->algorithm)) { - PK11_DestroyContext(into->d.ctx, PR_TRUE); - into->d.ctx = PK11_CloneContext(from->d.ctx); - return; - } -#endif - -#ifdef OPENSSL_HAS_SHA3 - if (from->algorithm == DIGEST_SHA3_256 || - from->algorithm == DIGEST_SHA3_512) { - EVP_MD_CTX_copy(into->d.md, from->d.md); - return; - } -#endif - - 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) -{ - /* 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); -#ifdef ENABLE_NSS - PK11SlotInfo *slot = NULL; - PK11SymKey *symKey = NULL; - PK11Context *hmac = NULL; - - int ok = 0; - SECStatus s; - SECItem keyItem, paramItem; - keyItem.data = (unsigned char *)key; - keyItem.len = (unsigned)key_len; - paramItem.type = siBuffer; - paramItem.data = NULL; - paramItem.len = 0; - - slot = PK11_GetBestSlot(CKM_SHA256_HMAC, NULL); - if (!slot) - goto done; - symKey = PK11_ImportSymKey(slot, CKM_SHA256_HMAC, - PK11_OriginUnwrap, CKA_SIGN, &keyItem, NULL); - if (!symKey) - goto done; - - hmac = PK11_CreateContextBySymKey(CKM_SHA256_HMAC, CKA_SIGN, symKey, - ¶mItem); - if (!hmac) - goto done; - s = PK11_DigestBegin(hmac); - if (s != SECSuccess) - goto done; - s = PK11_DigestOp(hmac, (const unsigned char *)msg, (unsigned int)msg_len); - if (s != SECSuccess) - goto done; - unsigned int len=0; - s = PK11_DigestFinal(hmac, (unsigned char *)hmac_out, &len, DIGEST256_LEN); - if (s != SECSuccess || len != DIGEST256_LEN) - goto done; - ok = 1; - - done: - if (hmac) - PK11_DestroyContext(hmac, PR_TRUE); - if (symKey) - PK11_FreeSymKey(symKey); - if (slot) - PK11_FreeSlot(slot); - - tor_assert(ok); -#else - unsigned char *rv = NULL; - rv = HMAC(EVP_sha256(), key, (int)key_len, (unsigned char*)msg, (int)msg_len, - (unsigned char*)hmac_out, NULL); - tor_assert(rv); -#endif -} - /** 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 diff --git a/src/lib/crypt_ops/crypto_digest_nss.c b/src/lib/crypt_ops/crypto_digest_nss.c new file mode 100644 index 000000000..b73f0736f --- /dev/null +++ b/src/lib/crypt_ops/crypto_digest_nss.c @@ -0,0 +1,560 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2019, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file crypto_digest_nss.c + * \brief Block of functions related with digest and xof utilities and + * operations (NSS specific implementations). + **/ + +#include "lib/container/smartlist.h" +#include "lib/crypt_ops/crypto_digest.h" +#include "lib/crypt_ops/crypto_util.h" +#include "lib/log/log.h" +#include "lib/log/util_bug.h" + +#include "keccak-tiny/keccak-tiny.h" + +#include <stdlib.h> +#include <string.h> + +#include "lib/arch/bytes.h" + +DISABLE_GCC_WARNING(strict-prototypes) +#include <pk11pub.h> +ENABLE_GCC_WARNING(strict-prototypes) + +/** + * Convert a digest_algorithm_t (used by tor) to a HashType (used by NSS). + * On failure, return SEC_OID_UNKNOWN. */ +static SECOidTag +digest_alg_to_nss_oid(digest_algorithm_t alg) +{ + switch (alg) { + case DIGEST_SHA1: return SEC_OID_SHA1; + case DIGEST_SHA256: return SEC_OID_SHA256; + case DIGEST_SHA512: return SEC_OID_SHA512; + case DIGEST_SHA3_256: /* Fall through */ + case DIGEST_SHA3_512: /* Fall through */ + default: + return SEC_OID_UNKNOWN; + } +} + +/* Helper: get an unkeyed digest via pk11wrap */ +static int +digest_nss_internal(SECOidTag alg, + char *digest, unsigned len_out, + const char *msg, size_t msg_len) +{ + if (alg == SEC_OID_UNKNOWN) + return -1; + tor_assert(msg_len <= UINT_MAX); + + int rv = -1; + SECStatus s; + PK11Context *ctx = PK11_CreateDigestContext(alg); + if (!ctx) + return -1; + + s = PK11_DigestBegin(ctx); + if (s != SECSuccess) + goto done; + + s = PK11_DigestOp(ctx, (const unsigned char *)msg, (unsigned int)msg_len); + if (s != SECSuccess) + goto done; + + unsigned int len = 0; + s = PK11_DigestFinal(ctx, (unsigned char *)digest, &len, len_out); + if (s != SECSuccess) + goto done; + + rv = 0; + done: + PK11_DestroyContext(ctx, PR_TRUE); + return rv; +} + +/** True iff alg is implemented in our crypto library, and we want to use that + * implementation */ +static bool +library_supports_digest(digest_algorithm_t alg) +{ + switch (alg) { + case DIGEST_SHA1: /* Fall through */ + case DIGEST_SHA256: /* Fall through */ + case DIGEST_SHA512: /* Fall through */ + return true; + case DIGEST_SHA3_256: /* Fall through */ + case DIGEST_SHA3_512: /* Fall through */ + default: + return false; + } +} + +/* Crypto digest functions */ + +/** 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. + */ +MOCK_IMPL(int, +crypto_digest,(char *digest, const char *m, size_t len)) +{ + tor_assert(m); + tor_assert(digest); + return digest_nss_internal(SEC_OID_SHA1, digest, DIGEST_LEN, m, len); +} + +/** 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) { + return digest_nss_internal(SEC_OID_SHA256, digest, DIGEST256_LEN, m, len); + } 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) { + return digest_nss_internal(SEC_OID_SHA512, digest, DIGEST512_LEN, m, len); + } else { + ret = (sha3_512((uint8_t*)digest, DIGEST512_LEN, (const uint8_t*)m, len) + > -1); + } + + if (!ret) + return -1; + return 0; +} + +/** 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 { + PK11Context *ctx; + 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: /* Fall through */ + case DIGEST_SHA256: /* Fall through */ + case DIGEST_SHA512: + return END_OF_FIELD(d.ctx); + 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: /* fall through */ + case DIGEST_SHA256: /* fall through */ + case DIGEST_SHA512: + r->d.ctx = PK11_CreateDigestContext(digest_alg_to_nss_oid(algorithm)); + if (BUG(!r->d.ctx)) { + tor_free(r); + return NULL; + } + if (BUG(SECSuccess != PK11_DigestBegin(r->d.ctx))) { + crypto_digest_free(r); + return NULL; + } + 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>. + * + * C_RUST_COUPLED: `external::crypto_digest::crypto_digest256_new` + * C_RUST_COUPLED: `crypto::digest::Sha256::default` + */ +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; + if (library_supports_digest(digest->algorithm)) { + PK11_DestroyContext(digest->d.ctx, PR_TRUE); + } + 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. + * + * C_RUST_COUPLED: `external::crypto_digest::crypto_digest_add_bytess` + * C_RUST_COUPLED: `crypto::digest::Sha256::process` + */ +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: /* fall through */ + case DIGEST_SHA256: /* fall through */ + case DIGEST_SHA512: + tor_assert(len <= UINT_MAX); + SECStatus s = PK11_DigestOp(digest->d.ctx, + (const unsigned char *)data, + (unsigned int)len); + tor_assert(s == SECSuccess); + 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. + * + * C_RUST_COUPLED: `external::crypto_digest::crypto_digest_get_digest` + * C_RUST_COUPLED: `impl digest::FixedOutput for Sha256` + */ +void +crypto_digest_get_digest(crypto_digest_t *digest, + char *out, size_t out_len) +{ + unsigned char r[DIGEST512_LEN]; + 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; + } + + /* Copy into a temporary buffer since DigestFinal (alters) the context */ + unsigned char buf[1024]; + unsigned int saved_len = 0; + unsigned rlen; + unsigned char *saved = PK11_SaveContextAlloc(digest->d.ctx, + buf, sizeof(buf), + &saved_len); + tor_assert(saved); + SECStatus s = PK11_DigestFinal(digest->d.ctx, r, &rlen, sizeof(r)); + tor_assert(s == SECSuccess); + tor_assert(rlen >= out_len); + s = PK11_RestoreContext(digest->d.ctx, saved, saved_len); + tor_assert(s == SECSuccess); + + if (saved != buf) { + PORT_ZFree(saved, saved_len); + } + 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> + * + * C_RUST_COUPLED: `external::crypto_digest::crypto_digest_dup` + * C_RUST_COUPLED: `impl Clone for crypto::digest::Sha256` + */ +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); + crypto_digest_t *result = tor_memdup(digest, alloc_bytes); + + if (library_supports_digest(digest->algorithm)) { + result->d.ctx = PK11_CloneContext(digest->d.ctx); + } + + return result; +} + +/** Temporarily save the state of <b>digest</b> in <b>checkpoint</b>. + * Asserts that <b>digest</b> is a SHA1 digest object. + */ +void +crypto_digest_checkpoint(crypto_digest_checkpoint_t *checkpoint, + const crypto_digest_t *digest) +{ + const size_t bytes = crypto_digest_alloc_bytes(digest->algorithm); + tor_assert(bytes <= sizeof(checkpoint->mem)); + if (library_supports_digest(digest->algorithm)) { + unsigned char *allocated; + allocated = PK11_SaveContextAlloc(digest->d.ctx, + (unsigned char *)checkpoint->mem, + sizeof(checkpoint->mem), + &checkpoint->bytes_used); + /* No allocation is allowed here. */ + tor_assert(allocated == checkpoint->mem); + return; + } + memcpy(checkpoint->mem, digest, bytes); +} + +/** Restore the state of <b>digest</b> from <b>checkpoint</b>. + * Asserts that <b>digest</b> is a SHA1 digest object. Requires that the + * state was previously stored with crypto_digest_checkpoint() */ +void +crypto_digest_restore(crypto_digest_t *digest, + const crypto_digest_checkpoint_t *checkpoint) +{ + const size_t bytes = crypto_digest_alloc_bytes(digest->algorithm); + if (library_supports_digest(digest->algorithm)) { + SECStatus s = PK11_RestoreContext(digest->d.ctx, + (unsigned char *)checkpoint->mem, + checkpoint->bytes_used); + tor_assert(s == SECSuccess); + return; + } + memcpy(digest, checkpoint->mem, 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); + if (library_supports_digest(from->algorithm)) { + PK11_DestroyContext(into->d.ctx, PR_TRUE); + into->d.ctx = PK11_CloneContext(from->d.ctx); + return; + } + 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) +{ + /* 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); + + PK11SlotInfo *slot = NULL; + PK11SymKey *symKey = NULL; + PK11Context *hmac = NULL; + + int ok = 0; + SECStatus s; + SECItem keyItem, paramItem; + keyItem.data = (unsigned char *)key; + keyItem.len = (unsigned)key_len; + paramItem.type = siBuffer; + paramItem.data = NULL; + paramItem.len = 0; + + slot = PK11_GetBestSlot(CKM_SHA256_HMAC, NULL); + if (!slot) + goto done; + symKey = PK11_ImportSymKey(slot, CKM_SHA256_HMAC, + PK11_OriginUnwrap, CKA_SIGN, &keyItem, NULL); + if (!symKey) + goto done; + + hmac = PK11_CreateContextBySymKey(CKM_SHA256_HMAC, CKA_SIGN, symKey, + ¶mItem); + if (!hmac) + goto done; + s = PK11_DigestBegin(hmac); + if (s != SECSuccess) + goto done; + s = PK11_DigestOp(hmac, (const unsigned char *)msg, (unsigned int)msg_len); + if (s != SECSuccess) + goto done; + unsigned int len=0; + s = PK11_DigestFinal(hmac, (unsigned char *)hmac_out, &len, DIGEST256_LEN); + if (s != SECSuccess || len != DIGEST256_LEN) + goto done; + ok = 1; + + done: + if (hmac) + PK11_DestroyContext(hmac, PR_TRUE); + if (symKey) + PK11_FreeSymKey(symKey); + if (slot) + PK11_FreeSlot(slot); + + tor_assert(ok); +} + diff --git a/src/lib/crypt_ops/crypto_digest_openssl.c b/src/lib/crypt_ops/crypto_digest_openssl.c new file mode 100644 index 000000000..a1c92351f --- /dev/null +++ b/src/lib/crypt_ops/crypto_digest_openssl.c @@ -0,0 +1,522 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2019, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file crypto_digest_openssl.c + * \brief Block of functions related with digest and xof utilities and + * operations (OpenSSL specific implementations). + **/ + +#include "lib/container/smartlist.h" +#include "lib/crypt_ops/crypto_digest.h" +#include "lib/crypt_ops/crypto_util.h" +#include "lib/log/log.h" +#include "lib/log/util_bug.h" + +#include "keccak-tiny/keccak-tiny.h" + +#include <stdlib.h> +#include <string.h> + +#include "lib/arch/bytes.h" + +#include "lib/crypt_ops/crypto_openssl_mgt.h" + +DISABLE_GCC_WARNING(redundant-decls) + +#include <openssl/hmac.h> +#include <openssl/sha.h> + +ENABLE_GCC_WARNING(redundant-decls) + +/* Crypto digest functions */ + +/** 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. + */ +MOCK_IMPL(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 { +#ifdef OPENSSL_HAS_SHA3 + unsigned int dlen = DIGEST256_LEN; + ret = EVP_Digest(m, len, (uint8_t*)digest, &dlen, EVP_sha3_256(), NULL); +#else + ret = (sha3_256((uint8_t *)digest, DIGEST256_LEN,(const uint8_t *)m, len) + > -1); +#endif + } + + 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 { +#ifdef OPENSSL_HAS_SHA3 + unsigned int dlen = DIGEST512_LEN; + ret = EVP_Digest(m, len, (uint8_t*)digest, &dlen, EVP_sha3_512(), NULL); +#else + ret = (sha3_512((uint8_t*)digest, DIGEST512_LEN, (const uint8_t*)m, len) + > -1); +#endif + } + + if (!ret) + return -1; + return 0; +} + +/** 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 */ +#ifdef OPENSSL_HAS_SHA3 + EVP_MD_CTX *md; +#else + keccak_state sha3; /**< state for SHA3-[256,512] */ +#endif + } 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); +#ifdef OPENSSL_HAS_SHA3 + case DIGEST_SHA3_256: /* Fall through */ + case DIGEST_SHA3_512: + return END_OF_FIELD(d.md); +#else + case DIGEST_SHA3_256: /* Fall through */ + case DIGEST_SHA3_512: + return END_OF_FIELD(d.sha3); +#endif + 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; +#ifdef OPENSSL_HAS_SHA3 + case DIGEST_SHA3_256: + r->d.md = EVP_MD_CTX_new(); + if (!EVP_DigestInit(r->d.md, EVP_sha3_256())) { + crypto_digest_free(r); + return NULL; + } + break; + case DIGEST_SHA3_512: + r->d.md = EVP_MD_CTX_new(); + if (!EVP_DigestInit(r->d.md, EVP_sha3_512())) { + crypto_digest_free(r); + return NULL; + } + break; +#else + case DIGEST_SHA3_256: + keccak_digest_init(&r->d.sha3, 256); + break; + case DIGEST_SHA3_512: + keccak_digest_init(&r->d.sha3, 512); + break; +#endif + 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>. + * + * C_RUST_COUPLED: `external::crypto_digest::crypto_digest256_new` + * C_RUST_COUPLED: `crypto::digest::Sha256::default` + */ +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; +#ifdef OPENSSL_HAS_SHA3 + if (digest->algorithm == DIGEST_SHA3_256 || + digest->algorithm == DIGEST_SHA3_512) { + if (digest->d.md) { + EVP_MD_CTX_free(digest->d.md); + } + } +#endif + 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. + * + * C_RUST_COUPLED: `external::crypto_digest::crypto_digest_add_bytess` + * C_RUST_COUPLED: `crypto::digest::Sha256::process` + */ +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; +#ifdef OPENSSL_HAS_SHA3 + case DIGEST_SHA3_256: /* FALLSTHROUGH */ + case DIGEST_SHA3_512: { + int r = EVP_DigestUpdate(digest->d.md, data, len); + tor_assert(r); + } + break; +#else + case DIGEST_SHA3_256: /* FALLSTHROUGH */ + case DIGEST_SHA3_512: + keccak_digest_update(&digest->d.sha3, (const uint8_t *)data, len); + break; +#endif + 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. + * + * C_RUST_COUPLED: `external::crypto_digest::crypto_digest_get_digest` + * C_RUST_COUPLED: `impl digest::FixedOutput for Sha256` + */ +void +crypto_digest_get_digest(crypto_digest_t *digest, + char *out, size_t out_len) +{ + unsigned char r[DIGEST512_LEN]; + 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) { +#ifdef OPENSSL_HAS_SHA3 + unsigned dlen = (unsigned) + crypto_digest_algorithm_get_length(digest->algorithm); + EVP_MD_CTX *tmp = EVP_MD_CTX_new(); + EVP_MD_CTX_copy(tmp, digest->d.md); + memset(r, 0xff, sizeof(r)); + int res = EVP_DigestFinal(tmp, r, &dlen); + EVP_MD_CTX_free(tmp); + tor_assert(res == 1); + goto done; +#else + /* Tiny-Keccak handles copying into a temporary ctx, and also can handle + * short output buffers by truncating appropriately. */ + keccak_digest_sum(&digest->d.sha3, (uint8_t *)out, out_len); + return; +#endif + } + + const size_t alloc_bytes = crypto_digest_alloc_bytes(digest->algorithm); + crypto_digest_t tmpenv; + /* 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 + } +#ifdef OPENSSL_HAS_SHA3 + done: +#endif + 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> + * + * C_RUST_COUPLED: `external::crypto_digest::crypto_digest_dup` + * C_RUST_COUPLED: `impl Clone for crypto::digest::Sha256` + */ +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); + crypto_digest_t *result = tor_memdup(digest, alloc_bytes); + +#ifdef OPENSSL_HAS_SHA3 + if (digest->algorithm == DIGEST_SHA3_256 || + digest->algorithm == DIGEST_SHA3_512) { + result->d.md = EVP_MD_CTX_new(); + EVP_MD_CTX_copy(result->d.md, digest->d.md); + } +#endif + return result; +} + +/** Temporarily save the state of <b>digest</b> in <b>checkpoint</b>. + * Asserts that <b>digest</b> is a SHA1 digest object. + */ +void +crypto_digest_checkpoint(crypto_digest_checkpoint_t *checkpoint, + const crypto_digest_t *digest) +{ + const size_t bytes = crypto_digest_alloc_bytes(digest->algorithm); + tor_assert(bytes <= sizeof(checkpoint->mem)); + memcpy(checkpoint->mem, digest, bytes); +} + +/** Restore the state of <b>digest</b> from <b>checkpoint</b>. + * Asserts that <b>digest</b> is a SHA1 digest object. Requires that the + * state was previously stored with crypto_digest_checkpoint() */ +void +crypto_digest_restore(crypto_digest_t *digest, + const crypto_digest_checkpoint_t *checkpoint) +{ + const size_t bytes = crypto_digest_alloc_bytes(digest->algorithm); + memcpy(digest, checkpoint->mem, 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); + +#ifdef OPENSSL_HAS_SHA3 + if (from->algorithm == DIGEST_SHA3_256 || + from->algorithm == DIGEST_SHA3_512) { + EVP_MD_CTX_copy(into->d.md, from->d.md); + return; + } +#endif + + 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) +{ + /* 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); + unsigned char *rv = NULL; + rv = HMAC(EVP_sha256(), key, (int)key_len, (unsigned char*)msg, (int)msg_len, + (unsigned char*)hmac_out, NULL); + tor_assert(rv); +} + diff --git a/src/lib/crypt_ops/include.am b/src/lib/crypt_ops/include.am index 473044014..c90ef6eca 100644 --- a/src/lib/crypt_ops/include.am +++ b/src/lib/crypt_ops/include.am @@ -27,12 +27,14 @@ src_lib_libtor_crypt_ops_a_SOURCES = \ if USE_NSS src_lib_libtor_crypt_ops_a_SOURCES += \ src/lib/crypt_ops/aes_nss.c \ + src/lib/crypt_ops/crypto_digest_nss.c \ src/lib/crypt_ops/crypto_dh_nss.c \ src/lib/crypt_ops/crypto_nss_mgt.c \ src/lib/crypt_ops/crypto_rsa_nss.c else src_lib_libtor_crypt_ops_a_SOURCES += \ src/lib/crypt_ops/aes_openssl.c \ + src/lib/crypt_ops/crypto_digest_openssl.c \ src/lib/crypt_ops/crypto_rsa_openssl.c endif