diff options
Diffstat (limited to 'src/common')
-rw-r--r-- | src/common/crypto.c | 44 | ||||
-rw-r--r-- | src/common/crypto.h | 6 | ||||
-rw-r--r-- | src/common/crypto_pwbox.c | 187 | ||||
-rw-r--r-- | src/common/crypto_pwbox.h | 20 | ||||
-rw-r--r-- | src/common/crypto_s2k.c | 457 | ||||
-rw-r--r-- | src/common/crypto_s2k.h | 73 | ||||
-rw-r--r-- | src/common/include.am | 8 |
7 files changed, 744 insertions, 51 deletions
diff --git a/src/common/crypto.c b/src/common/crypto.c index 014c83e850..fa91f6dd82 100644 --- a/src/common/crypto.c +++ b/src/common/crypto.c @@ -3001,50 +3001,6 @@ base32_decode(char *dest, size_t destlen, const char *src, size_t srclen) return 0; } -/** Implement RFC2440-style iterated-salted S2K conversion: convert the - * <b>secret_len</b>-byte <b>secret</b> into a <b>key_out_len</b> byte - * <b>key_out</b>. As in RFC2440, the first 8 bytes of s2k_specifier - * are a salt; the 9th byte describes how much iteration to do. - * Does not support <b>key_out_len</b> > DIGEST_LEN. - */ -void -secret_to_key(char *key_out, size_t key_out_len, const char *secret, - size_t secret_len, const char *s2k_specifier) -{ - crypto_digest_t *d; - uint8_t c; - size_t count, tmplen; - char *tmp; - tor_assert(key_out_len < SIZE_T_CEILING); - -#define EXPBIAS 6 - c = s2k_specifier[8]; - count = ((uint32_t)16 + (c & 15)) << ((c >> 4) + EXPBIAS); -#undef EXPBIAS - - tor_assert(key_out_len <= DIGEST_LEN); - - d = crypto_digest_new(); - tmplen = 8+secret_len; - tmp = tor_malloc(tmplen); - memcpy(tmp,s2k_specifier,8); - memcpy(tmp+8,secret,secret_len); - secret_len += 8; - while (count) { - if (count >= secret_len) { - crypto_digest_add_bytes(d, tmp, secret_len); - count -= secret_len; - } else { - crypto_digest_add_bytes(d, tmp, count); - count = 0; - } - } - crypto_digest_get_digest(d, key_out, key_out_len); - memwipe(tmp, 0, tmplen); - tor_free(tmp); - crypto_digest_free(d); -} - /** * Destroy the <b>sz</b> bytes of data stored at <b>mem</b>, setting them to * the value <b>byte</b>. diff --git a/src/common/crypto.h b/src/common/crypto.h index aa4271aa33..39bbdb5717 100644 --- a/src/common/crypto.h +++ b/src/common/crypto.h @@ -280,12 +280,6 @@ int digest_from_base64(char *digest, const char *d64); int digest256_to_base64(char *d64, const char *digest); int digest256_from_base64(char *digest, const char *d64); -/** Length of RFC2440-style S2K specifier: the first 8 bytes are a salt, the - * 9th describes how much iteration to do. */ -#define S2K_SPECIFIER_LEN 9 -void secret_to_key(char *key_out, size_t key_out_len, const char *secret, - size_t secret_len, const char *s2k_specifier); - /** OpenSSL-based utility functions. */ void memwipe(void *mem, uint8_t byte, size_t sz); diff --git a/src/common/crypto_pwbox.c b/src/common/crypto_pwbox.c new file mode 100644 index 0000000000..91659db2bc --- /dev/null +++ b/src/common/crypto_pwbox.c @@ -0,0 +1,187 @@ + +#include "crypto.h" +#include "crypto_s2k.h" +#include "crypto_pwbox.h" +#include "di_ops.h" +#include "util.h" +#include "pwbox.h" + +/* 8 bytes "TORBOX00" + 1 byte: header len (H) + H bytes: header, denoting secret key algorithm. + 16 bytes: IV + Round up to multiple of 128 bytes, then encrypt: + 4 bytes: data len + data + zeros + 32 bytes: HMAC-SHA256 of all previous bytes. +*/ + +#define MAX_OVERHEAD (S2K_MAXLEN + 8 + 1 + 32 + CIPHER_IV_LEN) + +/** + * Make an authenticated passphrase-encrypted blob to encode the + * <b>input_len</b> bytes in <b>input</b> using the passphrase + * <b>secret</b> of <b>secret_len</b> bytes. Allocate a new chunk of memory + * to hold the encrypted data, and store a pointer to that memory in + * *<b>out</b>, and its size in <b>outlen_out</b>. Use <b>s2k_flags</b> as an + * argument to the passphrase-hashing function. + */ +int +crypto_pwbox(uint8_t **out, size_t *outlen_out, + const uint8_t *input, size_t input_len, + const char *secret, size_t secret_len, + unsigned s2k_flags) +{ + uint8_t *result = NULL, *encrypted_portion; + size_t encrypted_len = 128 * CEIL_DIV(input_len+4, 128); + ssize_t result_len; + int spec_len; + uint8_t keys[CIPHER_KEY_LEN + DIGEST256_LEN]; + pwbox_encoded_t *enc = NULL; + ssize_t enc_len; + + crypto_cipher_t *cipher; + int rv; + + enc = pwbox_encoded_new(); + + pwbox_encoded_setlen_skey_header(enc, S2K_MAXLEN); + + spec_len = secret_to_key_make_specifier( + pwbox_encoded_getarray_skey_header(enc), + S2K_MAXLEN, + s2k_flags); + if (spec_len < 0 || spec_len > S2K_MAXLEN) + goto err; + pwbox_encoded_setlen_skey_header(enc, spec_len); + enc->header_len = spec_len; + + crypto_rand((char*)enc->iv, sizeof(enc->iv)); + + pwbox_encoded_setlen_data(enc, encrypted_len); + encrypted_portion = pwbox_encoded_getarray_data(enc); + + set_uint32(encrypted_portion, htonl(input_len)); + memcpy(encrypted_portion+4, input, input_len); + + /* Now that all the data is in position, derive some keys, encrypt, and + * digest */ + if (secret_to_key_derivekey(keys, sizeof(keys), + pwbox_encoded_getarray_skey_header(enc), + spec_len, + secret, secret_len) < 0) + goto err; + + cipher = crypto_cipher_new_with_iv((char*)keys, (char*)enc->iv); + crypto_cipher_crypt_inplace(cipher, (char*)encrypted_portion, encrypted_len); + crypto_cipher_free(cipher); + + result_len = pwbox_encoded_encoded_len(enc); + if (result_len < 0) + goto err; + result = tor_malloc(result_len); + enc_len = pwbox_encoded_encode(result, result_len, enc); + if (enc_len < 0) + goto err; + tor_assert(enc_len == result_len); + + crypto_hmac_sha256((char*) result + result_len - 32, + (const char*)keys + CIPHER_KEY_LEN, + DIGEST256_LEN, + (const char*)result, + result_len - 32); + + *out = result; + *outlen_out = result_len; + rv = 0; + goto out; + + err: + tor_free(result); + rv = -1; + + out: + pwbox_encoded_free(enc); + memwipe(keys, 0, sizeof(keys)); + return rv; +} + +/** + * Try to decrypt the passphrase-encrypted blob of <b>input_len</b> bytes in + * <b>input</b> using the passphrase <b>secret</b> of <b>secret_len</b> bytes. + * On success, return 0 and allocate a new chunk of memory to hold the + * decrypted data, and store a pointer to that memory in *<b>out</b>, and its + * size in <b>outlen_out</b>. On failure, return UNPWBOX_BAD_SECRET if + * the passphrase might have been wrong, and UNPWBOX_CORRUPT if the object is + * definitely corrupt. + */ +int +crypto_unpwbox(uint8_t **out, size_t *outlen_out, + const uint8_t *inp, size_t input_len, + const char *secret, size_t secret_len) +{ + uint8_t *result = NULL; + const uint8_t *encrypted; + uint8_t keys[CIPHER_KEY_LEN + DIGEST256_LEN]; + uint8_t hmac[DIGEST256_LEN]; + uint32_t result_len; + size_t encrypted_len; + crypto_cipher_t *cipher = NULL; + int rv = UNPWBOX_CORRUPTED; + ssize_t got_len; + + pwbox_encoded_t *enc = NULL; + + got_len = pwbox_encoded_parse(&enc, inp, input_len); + if (got_len < 0 || (size_t)got_len != input_len) + goto err; + + /* Now derive the keys and check the hmac. */ + if (secret_to_key_derivekey(keys, sizeof(keys), + pwbox_encoded_getarray_skey_header(enc), + pwbox_encoded_getlen_skey_header(enc), + secret, secret_len) < 0) + goto err; + + crypto_hmac_sha256((char *)hmac, + (const char*)keys + CIPHER_KEY_LEN, DIGEST256_LEN, + (const char*)inp, input_len - DIGEST256_LEN); + + if (tor_memneq(hmac, enc->hmac, DIGEST256_LEN)) { + rv = UNPWBOX_BAD_SECRET; + goto err; + } + + /* How long is the plaintext? */ + encrypted = pwbox_encoded_getarray_data(enc); + encrypted_len = pwbox_encoded_getlen_data(enc); + if (encrypted_len < 4) + goto err; + + cipher = crypto_cipher_new_with_iv((char*)keys, (char*)enc->iv); + crypto_cipher_decrypt(cipher, (char*)&result_len, (char*)encrypted, 4); + result_len = ntohl(result_len); + if (encrypted_len < result_len + 4) + goto err; + + /* Allocate a buffer and decrypt */ + result = tor_malloc_zero(result_len); + crypto_cipher_decrypt(cipher, (char*)result, (char*)encrypted+4, result_len); + + *out = result; + *outlen_out = result_len; + + rv = UNPWBOX_OKAY; + goto out; + + err: + tor_free(result); + + out: + crypto_cipher_free(cipher); + pwbox_encoded_free(enc); + memwipe(keys, 0, sizeof(keys)); + return rv; +} + diff --git a/src/common/crypto_pwbox.h b/src/common/crypto_pwbox.h new file mode 100644 index 0000000000..aadd477078 --- /dev/null +++ b/src/common/crypto_pwbox.h @@ -0,0 +1,20 @@ +#ifndef CRYPTO_PWBOX_H_INCLUDED_ +#define CRYPTO_PWBOX_H_INCLUDED_ + +#include "torint.h" + +#define UNPWBOX_OKAY 0 +#define UNPWBOX_BAD_SECRET -1 +#define UNPWBOX_CORRUPTED -2 + +int crypto_pwbox(uint8_t **out, size_t *outlen_out, + const uint8_t *inp, size_t input_len, + const char *secret, size_t secret_len, + unsigned s2k_flags); + +int crypto_unpwbox(uint8_t **out, size_t *outlen_out, + const uint8_t *inp, size_t input_len, + const char *secret, size_t secret_len); + +#endif + diff --git a/src/common/crypto_s2k.c b/src/common/crypto_s2k.c new file mode 100644 index 0000000000..93c96e74ae --- /dev/null +++ b/src/common/crypto_s2k.c @@ -0,0 +1,457 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * 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" +#include "crypto_s2k.h" + +#include <openssl/evp.h> + +#ifdef HAVE_LIBSCRYPT_H +#define HAVE_SCRYPT +#include <libscrypt.h> +#endif + +/* Encoded secrets take the form: + + u8 type; + u8 salt_and_parameters[depends on type]; + u8 key[depends on type]; + + As a special case, if the encoded secret is exactly 29 bytes long, + type 0 is understood. + + Recognized types are: + 00 -- RFC2440. salt_and_parameters is 9 bytes. key is 20 bytes. + salt_and_parameters is 8 bytes random salt, + 1 byte iteration info. + 01 -- PKBDF2_SHA1. salt_and_parameters is 17 bytes. key is 20 bytes. + salt_and_parameters is 16 bytes random salt, + 1 byte iteration info. + 02 -- SCRYPT_SALSA208_SHA256. salt_and_parameters is 18 bytes. key is + 32 bytes. + salt_and_parameters is 18 bytes random salt, 2 bytes iteration + info. +*/ + +#define S2K_TYPE_RFC2440 0 +#define S2K_TYPE_PBKDF2 1 +#define S2K_TYPE_SCRYPT 2 + +#define PBKDF2_SPEC_LEN 17 +#define PBKDF2_KEY_LEN 20 + +#define SCRYPT_SPEC_LEN 18 +#define SCRYPT_KEY_LEN 32 + +/** Given an algorithm ID (one of S2K_TYPE_*), return the length of the + * specifier part of it, without the prefix type byte. */ +static int +secret_to_key_spec_len(uint8_t type) +{ + switch (type) { + case S2K_TYPE_RFC2440: + return S2K_RFC2440_SPECIFIER_LEN; + case S2K_TYPE_PBKDF2: + return PBKDF2_SPEC_LEN; + case S2K_TYPE_SCRYPT: + return SCRYPT_SPEC_LEN; + default: + return -1; + } +} + +/** Given an algorithm ID (one of S2K_TYPE_*), return the length of the + * its preferred output. */ +static int +secret_to_key_key_len(uint8_t type) +{ + switch (type) { + case S2K_TYPE_RFC2440: + return DIGEST_LEN; + case S2K_TYPE_PBKDF2: + return DIGEST_LEN; + case S2K_TYPE_SCRYPT: + return DIGEST256_LEN; + default: + return -1; + } +} + +/** Given a specifier in <b>spec_and_key</b> of length + * <b>spec_and_key_len</b>, along with its prefix algorithm ID byte, and along + * with a key if <b>key_included</b> is true, check whether the whole + * specifier-and-key is of valid length, and return the algorithm type if it + * is. Set *<b>legacy_out</b> to 1 iff this is a legacy password hash or + * legacy specifier. Return an error code on failure. + */ +static int +secret_to_key_get_type(const uint8_t *spec_and_key, size_t spec_and_key_len, + int key_included, int *legacy_out) +{ + size_t legacy_len = S2K_RFC2440_SPECIFIER_LEN; + uint8_t type; + int total_len; + + if (key_included) + legacy_len += DIGEST_LEN; + + if (spec_and_key_len == legacy_len) { + *legacy_out = 1; + return S2K_TYPE_RFC2440; + } + + *legacy_out = 0; + if (spec_and_key_len == 0) + return S2K_BAD_LEN; + + type = spec_and_key[0]; + total_len = secret_to_key_spec_len(type); + if (total_len < 0) + return S2K_BAD_ALGORITHM; + if (key_included) { + int keylen = secret_to_key_key_len(type); + if (keylen < 0) + return S2K_BAD_ALGORITHM; + total_len += keylen; + } + + if ((size_t)total_len + 1 == spec_and_key_len) + return type; + else + return S2K_BAD_LEN; +} + +/** + * Write a new random s2k specifier of type <b>type</b>, without prefixing + * type byte, to <b>spec_out</b>, which must have enough room. May adjust + * parameter choice based on <b>flags</b>. + */ +static int +make_specifier(uint8_t *spec_out, uint8_t type, unsigned flags) +{ + int speclen = secret_to_key_spec_len(type); + if (speclen < 0) + return S2K_BAD_ALGORITHM; + + crypto_rand((char*)spec_out, speclen); + switch (type) { + case S2K_TYPE_RFC2440: + /* Hash 64 k of data. */ + spec_out[S2K_RFC2440_SPECIFIER_LEN-1] = 96; + break; + case S2K_TYPE_PBKDF2: + /* 131 K iterations */ + spec_out[PBKDF2_SPEC_LEN-1] = 17; + break; + case S2K_TYPE_SCRYPT: + if (flags & S2K_FLAG_LOW_MEM) { + /* N = 1<<12 */ + spec_out[SCRYPT_SPEC_LEN-2] = 12; + } else { + /* N = 1<<15 */ + spec_out[SCRYPT_SPEC_LEN-2] = 15; + } + /* r = 8; p = 2. */ + spec_out[SCRYPT_SPEC_LEN-1] = (3u << 4) | (1u << 0); + break; + default: + tor_fragile_assert(); + return S2K_BAD_ALGORITHM; + } + + return speclen; +} + +/** Implement RFC2440-style iterated-salted S2K conversion: convert the + * <b>secret_len</b>-byte <b>secret</b> into a <b>key_out_len</b> byte + * <b>key_out</b>. As in RFC2440, the first 8 bytes of s2k_specifier + * are a salt; the 9th byte describes how much iteration to do. + * If <b>key_out_len</b> > DIGEST_LEN, use HDKF to expand the result. + */ +void +secret_to_key_rfc2440(char *key_out, size_t key_out_len, const char *secret, + size_t secret_len, const char *s2k_specifier) +{ + crypto_digest_t *d; + uint8_t c; + size_t count, tmplen; + char *tmp; + uint8_t buf[DIGEST_LEN]; + tor_assert(key_out_len < SIZE_T_CEILING); + +#define EXPBIAS 6 + c = s2k_specifier[8]; + count = ((uint32_t)16 + (c & 15)) << ((c >> 4) + EXPBIAS); +#undef EXPBIAS + + d = crypto_digest_new(); + tmplen = 8+secret_len; + tmp = tor_malloc(tmplen); + memcpy(tmp,s2k_specifier,8); + memcpy(tmp+8,secret,secret_len); + secret_len += 8; + while (count) { + if (count >= secret_len) { + crypto_digest_add_bytes(d, tmp, secret_len); + count -= secret_len; + } else { + crypto_digest_add_bytes(d, tmp, count); + count = 0; + } + } + crypto_digest_get_digest(d, (char*)buf, sizeof(buf)); + + if (key_out_len <= sizeof(buf)) { + memcpy(key_out, buf, key_out_len); + } else { + crypto_expand_key_material_rfc5869_sha256(buf, DIGEST_LEN, + (const uint8_t*)s2k_specifier, 8, + (const uint8_t*)"EXPAND", 6, + (uint8_t*)key_out, key_out_len); + } + memwipe(tmp, 0, tmplen); + memwipe(buf, 0, sizeof(buf)); + tor_free(tmp); + crypto_digest_free(d); +} + +/** + * Helper: given a valid specifier without prefix type byte in <b>spec</b>, + * whose length must be correct, and given a secret passphrase <b>secret</b> + * of length <b>secret_len</b>, compute the key and store it into + * <b>key_out</b>, which must have enough room for secret_to_key_key_len(type) + * 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, size_t key_out_len, + const uint8_t *spec, size_t spec_len, + const char *secret, size_t secret_len, + int type) +{ + int rv; + if (key_out_len > INT_MAX) + return S2K_BAD_LEN; + + switch (type) { + case S2K_TYPE_RFC2440: + secret_to_key_rfc2440((char*)key_out, key_out_len, secret, secret_len, + (const char*)spec); + return (int)key_out_len; + + case S2K_TYPE_PBKDF2: { + uint8_t log_iters; + if (spec_len < 1 || secret_len > INT_MAX || spec_len > INT_MAX) + return S2K_BAD_LEN; + log_iters = spec[spec_len-1]; + if (log_iters > 31) + return S2K_BAD_PARAMS; + rv = PKCS5_PBKDF2_HMAC_SHA1(secret, (int)secret_len, + spec, (int)spec_len-1, + (1<<log_iters), + (int)key_out_len, key_out); + if (rv < 0) + return S2K_FAILED; + 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_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) << log_N; + r = 1u << log_r; + p = 1u << log_p; + rv = libscrypt_scrypt((const uint8_t*)secret, secret_len, + spec, spec_len-2, N, r, p, key_out, key_out_len); + if (rv != 0) + return S2K_FAILED; + return (int)key_out_len; +#else + return S2K_NO_SCRYPT_SUPPORT; +#endif + } + default: + return S2K_BAD_ALGORITHM; + } +} + +/** + * Given a specifier previously constructed with secret_to_key_make_specifier + * in <b>spec</b> of length <b>spec_len</b>, and a secret password in + * <b>secret</b> of length <b>secret_len</b>, generate <b>key_out_len</b> + * bytes of cryptographic material in <b>key_out</b>. The native output of + * the secret-to-key function will be truncated if key_out_len is short, and + * expanded with HKDF if key_out_len is long. Returns S2K_OKAY on success, + * and an error code on failure. + */ +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) +{ + int legacy_format = 0; + int type = secret_to_key_get_type(spec, spec_len, 0, &legacy_format); + int r; + + if (type < 0) + return type; +#ifndef HAVE_SCRYPT + if (type == S2K_TYPE_SCRYPT) + return S2K_NO_SCRYPT_SUPPORT; + #endif + + if (! legacy_format) { + ++spec; + --spec_len; + } + + r = secret_to_key_compute_key(key_out, key_out_len, spec, spec_len, + secret, secret_len, type); + if (r < 0) + return r; + else + return S2K_OKAY; +} + +/** + * Construct a new s2k algorithm specifier and salt in <b>buf</b>, according + * to the bitwise-or of some S2K_FLAG_* options in <b>flags</b>. Up to + * <b>buf_len</b> bytes of storage may be used in <b>buf</b>. Return the + * number of bytes used on success and an error code on failure. + */ +int +secret_to_key_make_specifier(uint8_t *buf, size_t buf_len, unsigned flags) +{ + int rv; + int spec_len; +#ifdef HAVE_SCRYPT + uint8_t type = S2K_TYPE_SCRYPT; +#else + uint8_t type = S2K_TYPE_RFC2440; +#endif + + if (flags & S2K_FLAG_NO_SCRYPT) + type = S2K_TYPE_RFC2440; + if (flags & S2K_FLAG_USE_PBKDF2) + type = S2K_TYPE_PBKDF2; + + spec_len = secret_to_key_spec_len(type); + + if ((int)buf_len < spec_len + 1) + return S2K_TRUNCATED; + + buf[0] = type; + rv = make_specifier(buf+1, type, flags); + if (rv < 0) + return rv; + else + return rv + 1; +} + +/** + * Hash a passphrase from <b>secret</b> of length <b>secret_len</b>, according + * to the bitwise-or of some S2K_FLAG_* options in <b>flags</b>, and store the + * hash along with salt and hashing parameters into <b>buf</b>. Up to + * <b>buf_len</b> bytes of storage may be used in <b>buf</b>. Set + * *<b>len_out</b> to the number of bytes used and return S2K_OKAY on success; + * and return an error code on failure. + */ +int +secret_to_key_new(uint8_t *buf, + size_t buf_len, + size_t *len_out, + const char *secret, size_t secret_len, + unsigned flags) +{ + int key_len; + int spec_len; + int type; + int rv; + + spec_len = secret_to_key_make_specifier(buf, buf_len, flags); + + if (spec_len < 0) + return spec_len; + + type = buf[0]; + key_len = secret_to_key_key_len(type); + + if ((int)buf_len < key_len + spec_len) + return S2K_TRUNCATED; + + 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; + + *len_out = spec_len + key_len; + + return S2K_OKAY; +} + +/** + * Given a hashed passphrase in <b>spec_and_key</b> of length + * <b>spec_and_key_len</b> as generated by secret_to_key_new(), verify whether + * it is a hash of the passphrase <b>secret</b> of length <b>secret_len</b>. + * Return S2K_OKAY on a match, S2K_BAD_SECRET on a well-formed hash that + * doesn't match this secret, and another error code on other errors. + */ +int +secret_to_key_check(const uint8_t *spec_and_key, size_t spec_and_key_len, + const char *secret, size_t secret_len) +{ + int is_legacy = 0; + int type = secret_to_key_get_type(spec_and_key, spec_and_key_len, + 1, &is_legacy); + uint8_t buf[32]; + int spec_len; + int key_len; + int rv; + + if (type < 0) + return type; + + if (! is_legacy) { + spec_and_key++; + spec_and_key_len--; + } + + spec_len = secret_to_key_spec_len(type); + key_len = secret_to_key_key_len(type); + tor_assert(spec_len > 0); + 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, key_len, + spec_and_key, spec_len, + secret, secret_len, type); + if (rv < 0) + goto done; + + if (tor_memeq(buf, spec_and_key + spec_len, key_len)) + rv = S2K_OKAY; + else + rv = S2K_BAD_SECRET; + + done: + memwipe(buf, 0, sizeof(buf)); + return rv; +} + diff --git a/src/common/crypto_s2k.h b/src/common/crypto_s2k.h new file mode 100644 index 0000000000..3693a430e7 --- /dev/null +++ b/src/common/crypto_s2k.h @@ -0,0 +1,73 @@ +/* Copyright (c) 2001, Matej Pfajfar. + * Copyright (c) 2001-2004, Roger Dingledine. + * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. + * Copyright (c) 2007-2013, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +#ifndef TOR_CRYPTO_S2K_H_INCLUDED +#define TOR_CRYPTO_S2K_H_INCLUDED + +#include <stdio.h> +#include "torint.h" + +/** Length of RFC2440-style S2K specifier: the first 8 bytes are a salt, the + * 9th describes how much iteration to do. */ +#define S2K_RFC2440_SPECIFIER_LEN 9 +void secret_to_key_rfc2440( + char *key_out, size_t key_out_len, const char *secret, + size_t secret_len, const char *s2k_specifier); + +/** Flag for secret-to-key function: do not use scrypt. */ +#define S2K_FLAG_NO_SCRYPT (1u<<0) +/** Flag for secret-to-key functions: if using a memory-tuned s2k function, + * assume that we have limited memory. */ +#define S2K_FLAG_LOW_MEM (1u<<1) +/** Flag for secret-to-key functions: force use of pbkdf2. Without this, we + * default to scrypt, then RFC2440. */ +#define S2K_FLAG_USE_PBKDF2 (1u<<2) + +/** Maximum possible output length from secret_to_key_new. */ +#define S2K_MAXLEN 64 + +/** Error code from secret-to-key functions: all is well */ +#define S2K_OKAY 0 +/** Error code from secret-to-key functions: generic failure */ +#define S2K_FAILED -1 +/** Error code from secret-to-key functions: provided secret didn't match */ +#define S2K_BAD_SECRET -2 +/** Error code from secret-to-key functions: didn't recognize the algorithm */ +#define S2K_BAD_ALGORITHM -3 +/** Error code from secret-to-key functions: specifier wasn't valid */ +#define S2K_BAD_PARAMS -4 +/** Error code from secret-to-key functions: compiled without scrypt */ +#define S2K_NO_SCRYPT_SUPPORT -5 +/** Error code from secret-to-key functions: not enough space to write output. + */ +#define S2K_TRUNCATED -6 +/** Error code from secret-to-key functions: Wrong length for specifier. */ +#define S2K_BAD_LEN -7 + +int secret_to_key_new(uint8_t *buf, + size_t buf_len, + size_t *len_out, + const char *secret, size_t secret_len, + unsigned flags); + +int secret_to_key_make_specifier(uint8_t *buf, size_t buf_len, unsigned flags); + +int secret_to_key_check(const uint8_t *spec_and_key, size_t spec_and_key_len, + const char *secret, size_t secret_len); + +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 + diff --git a/src/common/include.am b/src/common/include.am index 68e0110c26..d669cf473a 100644 --- a/src/common/include.am +++ b/src/common/include.am @@ -16,7 +16,7 @@ EXTRA_DIST+= \ src/common/Makefile.nmake #CFLAGS = -Wall -Wpointer-arith -O2 -AM_CPPFLAGS += -I$(srcdir)/src/common -Isrc/common +AM_CPPFLAGS += -I$(srcdir)/src/common -Isrc/common -I$(srcdir)/src/ext/trunnel -I$(srcdir)/src/trunnel if USE_OPENBSD_MALLOC libor_extra_source=src/ext/OpenBSD_malloc_Linux.c @@ -69,15 +69,19 @@ LIBOR_A_SOURCES = \ src/common/util_process.c \ src/common/sandbox.c \ src/ext/csiphash.c \ + src/ext/trunnel/trunnel.c \ $(libor_extra_source) \ $(libor_mempool_source) LIBOR_CRYPTO_A_SOURCES = \ src/common/aes.c \ src/common/crypto.c \ + src/common/crypto_pwbox.c \ + src/common/crypto_s2k.c \ src/common/crypto_format.c \ src/common/torgzip.c \ src/common/tortls.c \ + src/trunnel/pwbox.c \ $(libcrypto_extra_source) LIBOR_EVENT_A_SOURCES = \ @@ -110,6 +114,8 @@ COMMONHEADERS = \ src/common/container.h \ src/common/crypto.h \ src/common/crypto_curve25519.h \ + src/common/crypto_pwbox.h \ + src/common/crypto_s2k.h \ src/common/di_ops.h \ src/common/memarea.h \ src/common/linux_syscalls.inc \ |