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Diffstat (limited to 'server/util/crypto_sha512crypt.c')
-rw-r--r-- | server/util/crypto_sha512crypt.c | 382 |
1 files changed, 0 insertions, 382 deletions
diff --git a/server/util/crypto_sha512crypt.c b/server/util/crypto_sha512crypt.c deleted file mode 100644 index 9cd03a1e..00000000 --- a/server/util/crypto_sha512crypt.c +++ /dev/null @@ -1,382 +0,0 @@ -/* This file is based on nss_sha512crypt.c which is based on the work of - * Ulrich Drepper (http://people.redhat.com/drepper/SHA-crypt.txt). - * - * libcrypto is used to provide SHA512 and random number generation. - * (http://www.openssl.org/docs/crypto/crypto.html). - * - * Sumit Bose <sbose@redhat.com> - * George McCollister <georgem@novatech-llc.com> - */ -/* SHA512-based Unix crypt implementation. - Released into the Public Domain by Ulrich Drepper <drepper@redhat.com>. */ - -#define _GNU_SOURCE -#include <endian.h> -#include <errno.h> -#include <limits.h> -#include <stdbool.h> -#include <stdint.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <sys/param.h> -#include <sys/types.h> - -#include "util/util.h" - -#include <openssl/evp.h> -#include <openssl/rand.h> - -/* Define our magic string to mark salt for SHA512 "encryption" replacement. */ -const char sha512_salt_prefix[] = "$6$"; -#define SALT_PREF_SIZE (sizeof(sha512_salt_prefix) - 1) - -/* Prefix for optional rounds specification. */ -const char sha512_rounds_prefix[] = "rounds="; -#define ROUNDS_SIZE (sizeof(sha512_rounds_prefix) - 1) - -#define SALT_LEN_MAX 16 -#define ROUNDS_DEFAULT 5000 -#define ROUNDS_MIN 1000 -#define ROUNDS_MAX 999999999 - -/* Table with characters for base64 transformation. */ -const char b64t[64] = - "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; - -/* base64 conversion function */ -static inline void b64_from_24bit(char **dest, size_t *len, size_t n, - uint8_t b2, uint8_t b1, uint8_t b0) -{ - uint32_t w; - size_t i; - - if (*len < n) n = *len; - - w = (b2 << 16) | (b1 << 8) | b0; - for (i = 0; i < n; i++) { - (*dest)[i] = b64t[w & 0x3f]; - w >>= 6; - } - - *len -= i; - *dest += i; -} - -#define PTR_2_INT(x) ((x) - ((__typeof__ (x)) NULL)) -#define ALIGN64 __alignof__(uint64_t) - -static int sha512_crypt_r(const char *key, - const char *salt, - char *buffer, size_t buflen) -{ - unsigned char temp_result[64] __attribute__((__aligned__(ALIGN64))); - unsigned char alt_result[64] __attribute__((__aligned__(ALIGN64))); - size_t rounds = ROUNDS_DEFAULT; - bool rounds_custom = false; - EVP_MD_CTX alt_ctx; - EVP_MD_CTX ctx; - size_t salt_len; - size_t key_len; - size_t cnt; - char *copied_salt = NULL; - char *copied_key = NULL; - char *p_bytes = NULL; - char *s_bytes = NULL; - int p1, p2, p3, pt, n; - unsigned int part; - char *cp, *tmp; - int ret; - - /* Find beginning of salt string. The prefix should normally always be - * present. Just in case it is not. */ - if (strncmp(salt, sha512_salt_prefix, SALT_PREF_SIZE) == 0) { - /* Skip salt prefix. */ - salt += SALT_PREF_SIZE; - } - - if (strncmp(salt, sha512_rounds_prefix, ROUNDS_SIZE) == 0) { - unsigned long int srounds; - const char *num; - char *endp; - - num = salt + ROUNDS_SIZE; - srounds = strtoul(num, &endp, 10); - if (*endp == '$') { - salt = endp + 1; - if (srounds < ROUNDS_MIN) srounds = ROUNDS_MIN; - if (srounds > ROUNDS_MAX) srounds = ROUNDS_MAX; - rounds = srounds; - rounds_custom = true; - } - } - - salt_len = MIN(strcspn(salt, "$"), SALT_LEN_MAX); - key_len = strlen(key); - - if ((PTR_2_INT(key) % ALIGN64) != 0) { - tmp = (char *)alloca(key_len + ALIGN64); - key = copied_key = memcpy(tmp + ALIGN64 - PTR_2_INT(tmp) % ALIGN64, key, key_len); - } - - if (PTR_2_INT(salt) % ALIGN64 != 0) { - tmp = (char *)alloca(salt_len + ALIGN64); - salt = copied_salt = memcpy(tmp + ALIGN64 - PTR_2_INT(tmp) % ALIGN64, salt, salt_len); - } - - EVP_MD_CTX_init(&ctx); - - EVP_MD_CTX_init(&alt_ctx); - - /* Prepare for the real work. */ - if (!EVP_DigestInit_ex(&ctx, EVP_sha512(), NULL)) { - ret = EIO; - goto done; - } - - /* Add the key string. */ - EVP_DigestUpdate(&ctx, (const unsigned char *)key, key_len); - - /* The last part is the salt string. This must be at most 16 - * characters and it ends at the first `$' character (for - * compatibility with existing implementations). */ - EVP_DigestUpdate(&ctx, (const unsigned char *)salt, salt_len); - - - /* Compute alternate SHA512 sum with input KEY, SALT, and KEY. - * The final result will be added to the first context. */ - if (!EVP_DigestInit_ex(&alt_ctx, EVP_sha512(), NULL)) { - ret = EIO; - goto done; - } - - /* Add key. */ - EVP_DigestUpdate(&alt_ctx, (const unsigned char *)key, key_len); - - /* Add salt. */ - EVP_DigestUpdate(&alt_ctx, (const unsigned char *)salt, salt_len); - - /* Add key again. */ - EVP_DigestUpdate(&alt_ctx, (const unsigned char *)key, key_len); - - /* Now get result of this (64 bytes) and add it to the other context. */ - EVP_DigestFinal_ex(&alt_ctx, alt_result, &part); - - /* Add for any character in the key one byte of the alternate sum. */ - for (cnt = key_len; cnt > 64; cnt -= 64) { - EVP_DigestUpdate(&ctx, alt_result, 64); - } - EVP_DigestUpdate(&ctx, alt_result, cnt); - - /* Take the binary representation of the length of the key and for every - * 1 add the alternate sum, for every 0 the key. */ - for (cnt = key_len; cnt > 0; cnt >>= 1) { - if ((cnt & 1) != 0) { - EVP_DigestUpdate(&ctx, alt_result, 64); - } else { - EVP_DigestUpdate(&ctx, (const unsigned char *)key, key_len); - } - } - - /* Create intermediate result. */ - EVP_DigestFinal_ex(&ctx, alt_result, &part); - - /* Start computation of P byte sequence. */ - if (!EVP_DigestInit_ex(&alt_ctx, EVP_sha512(), NULL)) { - ret = EIO; - goto done; - } - - /* For every character in the password add the entire password. */ - for (cnt = 0; cnt < key_len; cnt++) { - EVP_DigestUpdate(&alt_ctx, (const unsigned char *)key, key_len); - } - - /* Finish the digest. */ - EVP_DigestFinal_ex(&alt_ctx, temp_result, &part); - - /* Create byte sequence P. */ - cp = p_bytes = alloca(key_len); - for (cnt = key_len; cnt >= 64; cnt -= 64) { - cp = mempcpy(cp, temp_result, 64); - } - memcpy(cp, temp_result, cnt); - - /* Start computation of S byte sequence. */ - if (!EVP_DigestInit_ex(&alt_ctx, EVP_sha512(), NULL)) { - ret = EIO; - goto done; - } - - /* For every character in the password add the entire salt. */ - for (cnt = 0; cnt < 16 + alt_result[0]; cnt++) { - EVP_DigestUpdate(&alt_ctx, (const unsigned char *)salt, salt_len); - } - - /* Finish the digest. */ - EVP_DigestFinal_ex(&alt_ctx, temp_result, &part); - - /* Create byte sequence S. */ - cp = s_bytes = alloca(salt_len); - for (cnt = salt_len; cnt >= 64; cnt -= 64) { - cp = mempcpy(cp, temp_result, 64); - } - memcpy(cp, temp_result, cnt); - - /* Repeatedly run the collected hash value through SHA512 to burn CPU cycles. */ - for (cnt = 0; cnt < rounds; cnt++) { - - if (!EVP_DigestInit_ex(&ctx, EVP_sha512(), NULL)) { - ret = EIO; - goto done; - } - - /* Add key or last result. */ - if ((cnt & 1) != 0) { - EVP_DigestUpdate(&ctx, (const unsigned char *)p_bytes, key_len); - } else { - EVP_DigestUpdate(&ctx, alt_result, 64); - } - - /* Add salt for numbers not divisible by 3. */ - if (cnt % 3 != 0) { - EVP_DigestUpdate(&ctx, (const unsigned char *)s_bytes, salt_len); - } - - /* Add key for numbers not divisible by 7. */ - if (cnt % 7 != 0) { - EVP_DigestUpdate(&ctx, (const unsigned char *)p_bytes, key_len); - } - - /* Add key or last result. */ - if ((cnt & 1) != 0) { - EVP_DigestUpdate(&ctx, alt_result, 64); - } else { - EVP_DigestUpdate(&ctx, (const unsigned char *)p_bytes, key_len); - } - - /* Create intermediate result. */ - EVP_DigestFinal_ex(&ctx, alt_result, &part); - } - - /* Now we can construct the result string. - * It consists of three parts. */ - if (buflen <= SALT_PREF_SIZE) { - ret = ERANGE; - goto done; - } - - cp = __stpncpy(buffer, sha512_salt_prefix, SALT_PREF_SIZE); - buflen -= SALT_PREF_SIZE; - - if (rounds_custom) { - n = snprintf(cp, buflen, "%s%zu$", - sha512_rounds_prefix, rounds); - if (n < 0 || n >= buflen) { - ret = ERANGE; - goto done; - } - cp += n; - buflen -= n; - } - - if (buflen <= salt_len + 1) { - ret = ERANGE; - goto done; - } - cp = __stpncpy(cp, salt, salt_len); - *cp++ = '$'; - buflen -= salt_len + 1; - - /* fuzzyfill the base 64 string */ - p1 = 0; - p2 = 21; - p3 = 42; - for (n = 0; n < 21; n++) { - b64_from_24bit(&cp, &buflen, 4, alt_result[p1], alt_result[p2], alt_result[p3]); - if (buflen == 0) { - ret = ERANGE; - goto done; - } - pt = p1; - p1 = p2 + 1; - p2 = p3 + 1; - p3 = pt + 1; - } - /* 64th and last byte */ - b64_from_24bit(&cp, &buflen, 2, 0, 0, alt_result[p3]); - if (buflen == 0) { - ret = ERANGE; - goto done; - } - - *cp = '\0'; - ret = EOK; - -done: - /* Clear the buffer for the intermediate result so that people attaching - * to processes or reading core dumps cannot get any information. We do it - * in this way to clear correct_words[] inside the SHA512 implementation - * as well. */ - EVP_MD_CTX_cleanup(&ctx); - EVP_MD_CTX_cleanup(&alt_ctx); - if (p_bytes) memset(p_bytes, '\0', key_len); - if (s_bytes) memset(s_bytes, '\0', salt_len); - if (copied_key) memset(copied_key, '\0', key_len); - if (copied_salt) memset(copied_salt, '\0', salt_len); - memset(temp_result, '\0', sizeof(temp_result)); - - return ret; -} - -int s3crypt_sha512(TALLOC_CTX *memctx, - const char *key, const char *salt, char **_hash) -{ - char *hash; - int hlen = (sizeof (sha512_salt_prefix) - 1 - + sizeof (sha512_rounds_prefix) + 9 + 1 - + strlen (salt) + 1 + 86 + 1); - int ret; - - hash = talloc_size(memctx, hlen); - if (!hash) return ENOMEM; - - ret = sha512_crypt_r(key, salt, hash, hlen); - if (ret) return ret; - - *_hash = hash; - return ret; -} - -#define SALT_RAND_LEN 12 - -int s3crypt_gen_salt(TALLOC_CTX *memctx, char **_salt) -{ - uint8_t rb[SALT_RAND_LEN]; - char *salt, *cp; - size_t slen; - int ret; - - salt = talloc_size(memctx, SALT_LEN_MAX + 1); - if (!salt) { - return ENOMEM; - } - - ret = RAND_bytes(rb, SALT_RAND_LEN); - if (ret == 0) { - return EIO; - } - - slen = SALT_LEN_MAX; - cp = salt; - b64_from_24bit(&cp, &slen, 4, rb[0], rb[1], rb[2]); - b64_from_24bit(&cp, &slen, 4, rb[3], rb[4], rb[5]); - b64_from_24bit(&cp, &slen, 4, rb[6], rb[7], rb[8]); - b64_from_24bit(&cp, &slen, 4, rb[9], rb[10], rb[11]); - *cp = '\0'; - - *_salt = salt; - - return EOK; -} - |