/* * wee-crypto.c - cryptographic functions * * Copyright (C) 2018-2022 Sébastien Helleu * * This file is part of WeeChat, the extensible chat client. * * WeeChat is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * WeeChat is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with WeeChat. If not, see . */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include #include #include #include #include #include "weechat.h" #include "wee-crypto.h" #include "wee-config-file.h" #include "wee-hashtable.h" #include "wee-string.h" #include "../plugins/plugin.h" char *weecrypto_hash_algo_string[] = { "crc32", "md5", "sha1", "sha224", "sha256", "sha384", "sha512", #if GCRYPT_VERSION_NUMBER >= 0x010700 "sha3-224", "sha3-256", "sha3-384", "sha3-512", #endif NULL, }; int weecrypto_hash_algo[] = { GCRY_MD_CRC32, GCRY_MD_MD5, GCRY_MD_SHA1, GCRY_MD_SHA224, GCRY_MD_SHA256, GCRY_MD_SHA384, GCRY_MD_SHA512, #if GCRYPT_VERSION_NUMBER >= 0x010700 GCRY_MD_SHA3_224, GCRY_MD_SHA3_256, GCRY_MD_SHA3_384, GCRY_MD_SHA3_512, #endif }; /* * Returns the hash algorithm with the name, or GCRY_MD_NONE if not found. */ int weecrypto_get_hash_algo (const char *hash_algo) { int i; if (!hash_algo) return GCRY_MD_NONE; for (i = 0; weecrypto_hash_algo_string[i]; i++) { if (strcmp (weecrypto_hash_algo_string[i], hash_algo) == 0) return weecrypto_hash_algo[i]; } return GCRY_MD_NONE; } /* * Computes hash of data using the given hash algorithm. * * The hash size depends on the algorithm, common ones are: * * GCRY_MD_CRC32 32 bits == 4 bytes * GCRY_MD_MD5 128 bits == 16 bytes * GCRY_MD_SHA1 160 bits == 20 bytes * GCRY_MD_SHA224 224 bits == 28 bytes * GCRY_MD_SHA256 256 bits == 32 bytes * GCRY_MD_SHA384 384 bits == 48 bytes * GCRY_MD_SHA512 512 bits == 64 bytes * GCRY_MD_SHA3_224 224 bits == 28 bytes (libgcrypt ≥ 1.7.0) * GCRY_MD_SHA3_256 256 bits == 32 bytes (libgcrypt ≥ 1.7.0) * GCRY_MD_SHA3_384 384 bits == 48 bytes (libgcrypt ≥ 1.7.0) * GCRY_MD_SHA3_512 512 bits == 64 bytes (libgcrypt ≥ 1.7.0) * * The result hash is stored in "hash" (the buffer must be large enough). * * If hash_size is not NULL, the length of hash is stored in *hash_size * (in bytes). * * Returns: * 1: OK * 0: error */ int weecrypto_hash (const void *data, int data_size, int hash_algo, void *hash, int *hash_size) { gcry_md_hd_t *hd_md; int rc, hd_md_opened, algo_size; unsigned char *ptr_hash; rc = 0; hd_md = NULL; hd_md_opened = 0; if (!hash) goto hash_end; if (hash_size) *hash_size = 0; if (!data || (data_size < 1)) goto hash_end; hd_md = malloc (sizeof (gcry_md_hd_t)); if (!hd_md) goto hash_end; if (gcry_md_open (hd_md, hash_algo, 0) != 0) goto hash_end; hd_md_opened = 1; gcry_md_write (*hd_md, data, data_size); ptr_hash = gcry_md_read (*hd_md, hash_algo); if (!ptr_hash) goto hash_end; algo_size = gcry_md_get_algo_dlen (hash_algo); memcpy (hash, ptr_hash, algo_size); if (hash_size) *hash_size = algo_size; rc = 1; hash_end: if (hd_md) { if (hd_md_opened) gcry_md_close (*hd_md); free (hd_md); } return rc; } /* * Computes hash of file using the given hash algorithm. * * The hash size depends on the algorithm, common ones are: * * GCRY_MD_CRC32 32 bits == 4 bytes * GCRY_MD_MD5 128 bits == 16 bytes * GCRY_MD_SHA1 160 bits == 20 bytes * GCRY_MD_SHA224 224 bits == 28 bytes * GCRY_MD_SHA256 256 bits == 32 bytes * GCRY_MD_SHA384 384 bits == 48 bytes * GCRY_MD_SHA512 512 bits == 64 bytes * GCRY_MD_SHA3_224 224 bits == 28 bytes (libgcrypt ≥ 1.7.0) * GCRY_MD_SHA3_256 256 bits == 32 bytes (libgcrypt ≥ 1.7.0) * GCRY_MD_SHA3_384 384 bits == 48 bytes (libgcrypt ≥ 1.7.0) * GCRY_MD_SHA3_512 512 bits == 64 bytes (libgcrypt ≥ 1.7.0) * * The result hash is stored in "hash" (the buffer must be large enough). * * If hash_size is not NULL, the length of hash is stored in *hash_size * (in bytes). * * Returns: * 1: OK * 0: error */ int weecrypto_hash_file (const char *filename, int hash_algo, void *hash, int *hash_size) { gcry_md_hd_t *hd_md; struct stat st; FILE *file; size_t num_read; int rc, hd_md_opened, algo_size; unsigned char *ptr_hash; char buffer[4096]; rc = 0; hd_md = NULL; hd_md_opened = 0; file = NULL; if (!hash) goto hash_end; if (hash_size) *hash_size = 0; if (!filename || !filename[0] || !hash) goto hash_end; if (stat (filename, &st) == -1) goto hash_end; file = fopen (filename, "r"); if (!file) goto hash_end; hd_md = malloc (sizeof (gcry_md_hd_t)); if (!hd_md) goto hash_end; if (gcry_md_open (hd_md, hash_algo, 0) != 0) goto hash_end; hd_md_opened = 1; while (!feof (file)) { num_read = fread (buffer, 1, sizeof (buffer), file); if (num_read == 0) break; gcry_md_write (*hd_md, buffer, num_read); } ptr_hash = gcry_md_read (*hd_md, hash_algo); if (!ptr_hash) goto hash_end; algo_size = gcry_md_get_algo_dlen (hash_algo); memcpy (hash, ptr_hash, algo_size); if (hash_size) *hash_size = algo_size; rc = 1; hash_end: if (hd_md) { if (hd_md_opened) gcry_md_close (*hd_md); free (hd_md); } if (file) fclose (file); return rc; } /* * Computes PKCS#5 Passphrase Based Key Derivation Function number 2 (PBKDF2) * hash of data. * * The hash size depends on the algorithm, common ones are: * * GCRY_MD_SHA1 160 bits == 20 bytes * GCRY_MD_SHA256 256 bits == 32 bytes * GCRY_MD_SHA512 512 bits == 64 bytes * * The result hash is stored in "hash" (the buffer must be large enough). * * If hash_size is not NULL, the length of hash is stored in *hash_size * (in bytes). * * Returns: * 1: OK * 0: error */ int weecrypto_hash_pbkdf2 (const void *data, int data_size, int hash_algo, const void *salt, int salt_size, int iterations, void *hash, int *hash_size) { int rc, algo_size; rc = 0; if (!hash) goto hash_pbkdf2_end; if (hash_size) *hash_size = 0; if (!data || (data_size < 1) || !salt || (salt_size < 1) || (iterations < 1)) { goto hash_pbkdf2_end; } algo_size = gcry_md_get_algo_dlen (hash_algo); if (gcry_kdf_derive (data, data_size, GCRY_KDF_PBKDF2, hash_algo, salt, salt_size, iterations, algo_size, hash) != 0) { goto hash_pbkdf2_end; } if (hash_size) *hash_size = algo_size; rc = 1; hash_pbkdf2_end: return rc; } /* * Computes keyed-hash message authentication code (HMAC). * * The hash size depends on the algorithm, common ones are: * * GCRY_MD_CRC32 32 bits == 4 bytes * GCRY_MD_MD5 128 bits == 16 bytes * GCRY_MD_SHA1 160 bits == 20 bytes * GCRY_MD_SHA224 224 bits == 28 bytes * GCRY_MD_SHA256 256 bits == 32 bytes * GCRY_MD_SHA384 384 bits == 48 bytes * GCRY_MD_SHA512 512 bits == 64 bytes * GCRY_MD_SHA3_224 224 bits == 28 bytes (libgcrypt ≥ 1.7.0) * GCRY_MD_SHA3_256 256 bits == 32 bytes (libgcrypt ≥ 1.7.0) * GCRY_MD_SHA3_384 384 bits == 48 bytes (libgcrypt ≥ 1.7.0) * GCRY_MD_SHA3_512 512 bits == 64 bytes (libgcrypt ≥ 1.7.0) * * The result hash is stored in "hash" (the buffer must be large enough). * * If hash_size is not NULL, the length of hash is stored in *hash_size * (in bytes). * * Returns: * 1: OK * 0: error */ int weecrypto_hmac (const void *key, int key_size, const void *message, int message_size, int hash_algo, void *hash, int *hash_size) { gcry_md_hd_t *hd_md; int rc, hd_md_opened, algo_size; unsigned char *ptr_hash; rc = 0; hd_md = NULL; hd_md_opened = 0; if (!hash) goto hmac_end; if (hash_size) *hash_size = 0; if (!key || (key_size < 1) || !message || (message_size < 1)) goto hmac_end; hd_md = malloc (sizeof (gcry_md_hd_t)); if (!hd_md) goto hmac_end; if (gcry_md_open (hd_md, hash_algo, GCRY_MD_FLAG_HMAC) != 0) goto hmac_end; hd_md_opened = 1; if (gcry_md_setkey (*hd_md, key, key_size) != 0) goto hmac_end; gcry_md_write (*hd_md, message, message_size); ptr_hash = gcry_md_read (*hd_md, hash_algo); if (!ptr_hash) goto hmac_end; algo_size = gcry_md_get_algo_dlen (hash_algo); memcpy (hash, ptr_hash, algo_size); if (hash_size) *hash_size = algo_size; rc = 1; hmac_end: if (hd_md) { if (hd_md_opened) gcry_md_close (*hd_md); free (hd_md); } return rc; } /* * Generates a Time-based One-Time Password (TOTP), as described * in the RFC 6238. * * Returns: * 1: OK * 0: error */ int weecrypto_totp_generate_internal (const char *secret, int length_secret, uint64_t moving_factor, int digits, char *result) { uint64_t moving_factor_swapped; char hash[20]; int rc, offset, length; unsigned long bin_code; moving_factor_swapped = (moving_factor >> 56) | ((moving_factor << 40) & 0x00FF000000000000) | ((moving_factor << 24) & 0x0000FF0000000000) | ((moving_factor << 8) & 0x000000FF00000000) | ((moving_factor >> 8) & 0x00000000FF000000) | ((moving_factor >> 24) & 0x0000000000FF0000) | ((moving_factor >> 40) & 0x000000000000FF00) | (moving_factor << 56); rc = weecrypto_hmac (secret, length_secret, &moving_factor_swapped, sizeof (moving_factor_swapped), GCRY_MD_SHA1, hash, NULL); if (!rc) return 0; offset = hash[19] & 0xf; bin_code = (hash[offset] & 0x7f) << 24 | (hash[offset+1] & 0xff) << 16 | (hash[offset+2] & 0xff) << 8 | (hash[offset+3] & 0xff); bin_code %= (unsigned long)(pow (10, digits)); length = snprintf (result, digits + 1, "%.*lu", digits, bin_code); if (length != digits) return 0; return 1; } /* * Generates a Time-based One-Time Password (TOTP), as described * in the RFC 6238. * * Returns the password as string, NULL if error. * * Note: result must be freed after use. */ char * weecrypto_totp_generate (const char *secret_base32, time_t totp_time, int digits) { char *result, *secret; int length_secret, rc; uint64_t moving_factor; secret = NULL; result = NULL; if (!secret_base32 || !secret_base32[0] || (digits < WEECRYPTO_TOTP_MIN_DIGITS) || (digits > WEECRYPTO_TOTP_MAX_DIGITS)) { goto error; } secret = malloc ((strlen (secret_base32) * 4) + 16 + 1); if (!secret) goto error; length_secret = string_base32_decode (secret_base32, secret); if (length_secret < 0) goto error; result = malloc (digits + 1); if (!result) goto error; if (totp_time == 0) totp_time = time (NULL); moving_factor = totp_time / 30; rc = weecrypto_totp_generate_internal (secret, length_secret, moving_factor, digits, result); if (!rc) goto error; free (secret); return result; error: if (secret) free (secret); if (result) free (result); return NULL; } /* * Validates a Time-based One-Time Password (TOTP). * * Returns: * 1: OTP is OK * 0: OTP is invalid */ int weecrypto_totp_validate (const char *secret_base32, time_t totp_time, int window, const char *otp) { char *secret, str_otp[16]; int length_secret, digits, rc, otp_ok; uint64_t i, moving_factor; secret = NULL; if (!secret_base32 || !secret_base32[0] || (window < 0) || !otp || !otp[0]) goto error; digits = strlen (otp); if ((digits < WEECRYPTO_TOTP_MIN_DIGITS) || (digits > WEECRYPTO_TOTP_MAX_DIGITS)) { goto error; } secret = malloc (strlen (secret_base32) + 1); if (!secret) goto error; length_secret = string_base32_decode (secret_base32, secret); if (length_secret < 0) goto error; if (totp_time == 0) totp_time = time (NULL); moving_factor = totp_time / 30; otp_ok = 0; for (i = moving_factor - window; i <= moving_factor + window; i++) { rc = weecrypto_totp_generate_internal (secret, length_secret, i, digits, str_otp); if (rc && (strcmp (str_otp, otp) == 0)) { otp_ok = 1; break; } } free (secret); return otp_ok; error: if (secret) free (secret); return 0; }