commit 2b2cab41414fddd0221b2f5c2f3010131ae81df4 Author: Nick Mathewson <nickm@torproject.org> Date: Sat Aug 30 10:42:02 2014 -0400 Tweak and expose secret_to_key_compute_key for testing Doing this lets me pass in a salt of an unusual length. --- src/common/crypto_s2k.c | 59 +++++++++++++++++++++++++++++------------------ src/common/crypto_s2k.h | 7 ++++++ 2 files changed, 43 insertions(+), 23 deletions(-) diff --git a/src/common/crypto_s2k.c b/src/common/crypto_s2k.c index 8f08a22..658a773 100644 --- a/src/common/crypto_s2k.c +++ b/src/common/crypto_s2k.c @@ -4,6 +4,8 @@ * Copyright (c) 2007-2013, The Tor Project, Inc. */ /* See LICENSE for licensing information */ +#define CRYPTO_S2K_PRIVATE + #include "crypto.h" #include "util.h" #include "compat.h" @@ -219,8 +221,9 @@ secret_to_key_rfc2440(char *key_out, size_t key_out_len, const char *secret, * bytes. Return the number of bytes written on success and an error code * on failure. */ -static int -secret_to_key_compute_key(uint8_t *key_out, const uint8_t *spec, +STATIC int +secret_to_key_compute_key(uint8_t *key_out, size_t key_out_len, + const uint8_t *spec, size_t spec_len, const char *secret, size_t secret_len, int type) { @@ -233,36 +236,44 @@ secret_to_key_compute_key(uint8_t *key_out, const uint8_t *spec, return DIGEST_LEN; case S2K_TYPE_PBKDF2: { - int iters; - if (spec[16] > 31) - return S2K_BAD_PARAMS; - if (secret_len > INT_MAX) + uint8_t log_iters; + if (spec_len < 1 || secret_len > INT_MAX || spec_len > INT_MAX || + key_out_len > INT_MAX) return S2K_BAD_LEN; - iters = 1 << spec[16]; + log_iters = spec[spec_len-1]; + if (log_iters > 31) + return S2K_BAD_PARAMS; rv = PKCS5_PBKDF2_HMAC_SHA1(secret, (int)secret_len, - spec, 16, - 1<<spec[16], - DIGEST_LEN, key_out); - + spec, (int)spec_len-1, + (1<<log_iters), + (int)key_out_len, key_out); if (rv < 0) return S2K_FAILED; - return DIGEST_LEN; + return (int)key_out_len; } case S2K_TYPE_SCRYPT: { #ifdef HAVE_SCRYPT + uint8_t log_N, log_r, log_p; uint64_t N; uint32_t r, p; - if (spec[16] > 63) + if (key_out_len > INT_MAX) + return S2K_BAD_LEN; + if (spec_len < 2) + return S2K_BAD_LEN; + log_N = spec[spec_len-2]; + log_r = (spec[spec_len-1]) >> 4; + log_p = (spec[spec_len-1]) & 15; + if (log_N > 63) return S2K_BAD_PARAMS; - N = ((uint64_t)1) << spec[16]; - r = 1u << (spec[17] >> 4); - p = 1u << (spec[17] & 15); + N = ((uint64_t)1) << log_N; + r = 1u << log_r; + p = 1u << log_p; rv = libscrypt_scrypt((const uint8_t*)secret, secret_len, - spec, 16, N, r, p, key_out, 32); - if (rv < 0) + spec, spec_len-2, N, r, p, key_out, key_out_len); + if (rv != 0) return S2K_FAILED; - return DIGEST256_LEN; + return (int)key_out_len; #else return S2K_NO_SCRYPT_SUPPORT; #endif @@ -307,7 +318,8 @@ secret_to_key_derivekey(uint8_t *key_out, size_t key_out_len, tor_assert(keylen > 0); tor_assert(keylen <= (int)sizeof(buf)); - r = secret_to_key_compute_key(buf, spec, secret, secret_len, type); + r = secret_to_key_compute_key(buf, keylen, spec, spec_len, + secret, secret_len, type); if (r < 0) return r; @@ -397,7 +409,8 @@ secret_to_key_new(uint8_t *buf, if ((int)buf_len < key_len + spec_len) return S2K_TRUNCATED; - rv = secret_to_key_compute_key(buf + spec_len, buf + 1, + rv = secret_to_key_compute_key(buf + spec_len, key_len, + buf + 1, spec_len-1, secret, secret_len, type); if (rv < 0) return rv; @@ -440,8 +453,8 @@ secret_to_key_check(const uint8_t *spec_and_key, size_t spec_and_key_len, tor_assert(key_len > 0); tor_assert(key_len <= (int) sizeof(buf)); tor_assert((int)spec_and_key_len == spec_len + key_len); - rv = secret_to_key_compute_key(buf, - spec_and_key, + rv = secret_to_key_compute_key(buf, key_len, + spec_and_key, spec_len, secret, secret_len, type); if (rv < 0) goto done; diff --git a/src/common/crypto_s2k.h b/src/common/crypto_s2k.h index abd8014..3693a43 100644 --- a/src/common/crypto_s2k.h +++ b/src/common/crypto_s2k.h @@ -62,5 +62,12 @@ int secret_to_key_derivekey(uint8_t *key_out, size_t key_out_len, const uint8_t *spec, size_t spec_len, const char *secret, size_t secret_len); +#ifdef CRYPTO_S2K_PRIVATE +STATIC int secret_to_key_compute_key(uint8_t *key_out, size_t key_out_len, + const uint8_t *spec, size_t spec_len, + const char *secret, size_t secret_len, + int type); +#endif + #endif