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author | Nick Mathewson <nickm@torproject.org> | 2018-03-26 19:52:58 -0400 |
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committer | Nick Mathewson <nickm@torproject.org> | 2018-03-26 20:12:59 -0400 |
commit | 0eed0899cdeadd84dc5323f8ca0a3a13cd3779de (patch) | |
tree | 78078494701e80ecb461dd01b173cb51da9c4977 /src/common/crypto.c | |
parent | d96dc2060a0470a4607db6f2991ea7c2c3508e23 (diff) | |
parent | 7759ac8df2944aa58fff4152dd2c4c521f78ef10 (diff) | |
download | tor-0eed0899cdeadd84dc5323f8ca0a3a13cd3779de.tar.gz tor-0eed0899cdeadd84dc5323f8ca0a3a13cd3779de.zip |
Merge branch 'bug24658-rm-curve25519-header' into bug24658-merge
Diffstat (limited to 'src/common/crypto.c')
-rw-r--r-- | src/common/crypto.c | 803 |
1 files changed, 1 insertions, 802 deletions
diff --git a/src/common/crypto.c b/src/common/crypto.c index ade8b0191f..9fcd17742c 100644 --- a/src/common/crypto.c +++ b/src/common/crypto.c @@ -29,6 +29,7 @@ #include "crypto_ed25519.h" #include "crypto_format.h" #include "crypto_rsa.h" +#include "crypto_digest.h" DISABLE_GCC_WARNING(redundant-decls) @@ -397,266 +398,6 @@ 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 @@ -788,548 +529,6 @@ 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); -} - -/** 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); - 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 */ |