cpp_src/tools/shacrypt.cc - master - uzer_007/reindexer

cpp_src/tools/shacrypt.cc
337 строк10 KB
madschemas
Update to version v5.0.0
04 мар 2025, 15:17
04 мар 2025, 15:1703771e3
#include "crypt.h"
/*
 * Copied from https://github.com/openssl/openssl/blob/master/apps/passwd.c
 */

/*
 * Copyright 2000-2022 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

namespace reindexer {

#ifdef WITH_OPENSSL
static const unsigned char cov_2char[64] = {
	/* from crypto/des/fcrypt.c */
	0x2E, 0x2F, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4A,
	0x4B, 0x4C, 0x4D, 0x4E, 0x4F, 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66,
	0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A};

static const char ascii_dollar[] = {0x24, 0x00};

/*
 * SHA based password algorithm, describe by Ulrich Drepper here:
 * https://www.akkadia.org/drepper/SHA-crypt.txt
 * (note that it's in the public domain)
 */
std::string shacrypt(const char* passwd, const char* magic, const char* salt) {
	assertrx_dbg(openssl::LibCryptoAvailable());

#define DLSYM(sym) [[maybe_unused]] auto sym = openssl::sym;
	LIBCRYPTO_EXPAND_MACRO_LIST(DLSYM)

	/* Prefix for optional rounds specification.  */
	static const char rounds_prefix[] = "rounds=";
	/* Maximum salt string length.  */
#define SALT_LEN_MAX 16
	/* Default number of rounds if not explicitly specified.  */
#define ROUNDS_DEFAULT 5000
	/* Minimum number of rounds.  */
#define ROUNDS_MIN 1000
	/* Maximum number of rounds.  */
#define ROUNDS_MAX 999999999

	/* "$6$rounds=<N>$......salt......$...shahash(up to 86 chars)...\0" */
	char out_buf[3 + 17 + 17 + 86 + 1];
	unsigned char buf[SHA512_DIGEST_LENGTH];
	unsigned char temp_buf[SHA512_DIGEST_LENGTH];
	size_t buf_size = 0;
	char ascii_magic[2];
	char ascii_salt[17]; /* Max 16 chars plus '\0' */
	char* ascii_passwd = NULL;
	size_t n;
	EVP_MD_CTX *md = NULL, *md2 = NULL;
	const EVP_MD* sha = NULL;
	size_t passwd_len, salt_len, magic_len;
	unsigned int rounds = ROUNDS_DEFAULT; /* Default */
	char rounds_custom = 0;
	char* p_bytes = NULL;
	char* s_bytes = NULL;
	char* cp = NULL;

	passwd_len = strlen(passwd);
	magic_len = strlen(magic);

	/* assert it's "5" or "6" */
	if (magic_len != 1) {
		return {};
	}

	switch (magic[0]) {
		case '5':
			sha = EVP_sha256();
			buf_size = 32;
			break;
		case '6':
			sha = EVP_sha512();
			buf_size = 64;
			break;
		default:
			return {};
	}

	if (strncmp(salt, rounds_prefix, sizeof(rounds_prefix) - 1) == 0) {
		const char* num = salt + sizeof(rounds_prefix) - 1;
		char* endp;
		unsigned long int srounds = strtoul(num, &endp, 10);
		if (*endp == '$') {
			salt = endp + 1;
			if (srounds > ROUNDS_MAX) {
				rounds = ROUNDS_MAX;
			} else if (srounds < ROUNDS_MIN) {
				rounds = ROUNDS_MIN;
			} else {
				rounds = unsigned(srounds);
			}
			rounds_custom = 1;
		} else {
			return {};
		}
	}

	OPENSSL_strlcpy(ascii_magic, magic, sizeof(ascii_magic));
#ifdef CHARSET_EBCDIC
	if ((magic[0] & 0x80) != 0) { /* High bit is 1 in EBCDIC alnums */
		ebcdic2ascii(ascii_magic, ascii_magic, magic_len);
	}
#endif

	/* The salt gets truncated to 16 chars */
	OPENSSL_strlcpy(ascii_salt, salt, sizeof(ascii_salt));
	salt_len = strlen(ascii_salt);
#ifdef CHARSET_EBCDIC
	ebcdic2ascii(ascii_salt, ascii_salt, salt_len);
#endif

#ifdef CHARSET_EBCDIC
	ascii_passwd = OPENSSL_strdup(passwd);
	if (ascii_passwd == NULL) {
		return {};
	}
	ebcdic2ascii(ascii_passwd, ascii_passwd, passwd_len);
	passwd = ascii_passwd;
#endif

	out_buf[0] = 0;
	OPENSSL_strlcat(out_buf, ascii_dollar, sizeof(out_buf));
	OPENSSL_strlcat(out_buf, ascii_magic, sizeof(out_buf));
	OPENSSL_strlcat(out_buf, ascii_dollar, sizeof(out_buf));
	if (rounds_custom) {
		char tmp_buf[80]; /* "rounds=999999999" */
		snprintf(tmp_buf, sizeof(tmp_buf), "rounds=%u", rounds);

#ifdef CHARSET_EBCDIC
		/* In case we're really on a ASCII based platform and just pretend */
		if (tmp_buf[0] != 0x72) { /* ASCII 'r' */
			ebcdic2ascii(tmp_buf, tmp_buf, strlen(tmp_buf));
		}
#endif
		OPENSSL_strlcat(out_buf, tmp_buf, sizeof(out_buf));
		OPENSSL_strlcat(out_buf, ascii_dollar, sizeof(out_buf));
	}
	OPENSSL_strlcat(out_buf, ascii_salt, sizeof(out_buf));

	/* assert "$5$rounds=999999999$......salt......" */
	if (strlen(out_buf) > 3 + 17 * rounds_custom + salt_len) {
		goto err;
	}

	md = EVP_MD_CTX_new();
	if (md == NULL || !EVP_DigestInit_ex(md, sha, NULL) || !EVP_DigestUpdate(md, passwd, passwd_len) ||
		!EVP_DigestUpdate(md, ascii_salt, salt_len)) {
		goto err;
	}

	md2 = EVP_MD_CTX_new();
	if (md2 == NULL || !EVP_DigestInit_ex(md2, sha, NULL) || !EVP_DigestUpdate(md2, passwd, passwd_len) ||
		!EVP_DigestUpdate(md2, ascii_salt, salt_len) || !EVP_DigestUpdate(md2, passwd, passwd_len) || !EVP_DigestFinal_ex(md2, buf, NULL)) {
		goto err;
	}

	for (n = passwd_len; n > buf_size; n -= buf_size) {
		if (!EVP_DigestUpdate(md, buf, buf_size)) {
			goto err;
		}
	}
	if (!EVP_DigestUpdate(md, buf, n)) {
		goto err;
	}

	n = passwd_len;
	while (n) {
		if (!EVP_DigestUpdate(md, (n & 1) ? buf : reinterpret_cast<const unsigned char*>(passwd), (n & 1) ? buf_size : passwd_len)) {
			goto err;
		}
		n >>= 1;
	}
	if (!EVP_DigestFinal_ex(md, buf, NULL)) {
		goto err;
	}

	/* P sequence */
	if (!EVP_DigestInit_ex(md2, sha, NULL)) {
		goto err;
	}

	for (n = passwd_len; n > 0; n--) {
		if (!EVP_DigestUpdate(md2, passwd, passwd_len)) {
			goto err;
		}
	}

	if (!EVP_DigestFinal_ex(md2, temp_buf, NULL)) {
		goto err;
	}

	if ((p_bytes = reinterpret_cast<char*>(OPENSSL_zalloc(passwd_len))) == NULL) {
		goto err;
	}
	for (cp = p_bytes, n = passwd_len; n > buf_size; n -= buf_size, cp += buf_size) {
		memcpy(cp, temp_buf, buf_size);
	}
	memcpy(cp, temp_buf, n);

	/* S sequence */
	if (!EVP_DigestInit_ex(md2, sha, NULL)) {
		goto err;
	}

	for (n = 16 + buf[0]; n > 0; n--) {
		if (!EVP_DigestUpdate(md2, ascii_salt, salt_len)) {
			goto err;
		}
	}

	if (!EVP_DigestFinal_ex(md2, temp_buf, NULL)) {
		goto err;
	}

	if ((s_bytes = reinterpret_cast<char*>(OPENSSL_zalloc(salt_len))) == NULL) {
		goto err;
	}
	for (cp = s_bytes, n = salt_len; n > buf_size; n -= buf_size, cp += buf_size) {
		memcpy(cp, temp_buf, buf_size);
	}
	memcpy(cp, temp_buf, n);

	for (n = 0; n < rounds; n++) {
		if (!EVP_DigestInit_ex(md2, sha, NULL)) {
			goto err;
		}
		if (!EVP_DigestUpdate(md2, (n & 1) ? reinterpret_cast<const unsigned char*>(p_bytes) : buf, (n & 1) ? passwd_len : buf_size)) {
			goto err;
		}
		if (n % 3) {
			if (!EVP_DigestUpdate(md2, s_bytes, salt_len)) {
				goto err;
			}
		}
		if (n % 7) {
			if (!EVP_DigestUpdate(md2, p_bytes, passwd_len)) {
				goto err;
			}
		}
		if (!EVP_DigestUpdate(md2, (n & 1) ? buf : reinterpret_cast<const unsigned char*>(p_bytes), (n & 1) ? buf_size : passwd_len)) {
			goto err;
		}
		if (!EVP_DigestFinal_ex(md2, buf, NULL)) {
			goto err;
		}
	}
	EVP_MD_CTX_free(md2);
	EVP_MD_CTX_free(md);
	md2 = NULL;
	md = NULL;
	OPENSSL_free(p_bytes);
	OPENSSL_free(s_bytes);
	p_bytes = NULL;
	s_bytes = NULL;

	cp = out_buf + strlen(out_buf);
	*cp++ = ascii_dollar[0];

#define b64_from_24bit(B2, B1, B0, N)                       \
	do {                                                    \
		unsigned int w = ((B2) << 16) | ((B1) << 8) | (B0); \
		int i = (N);                                        \
		while (i-- > 0) {                                   \
			*cp++ = cov_2char[w & 0x3f];                    \
			w >>= 6;                                        \
		}                                                   \
	} while (0)

	switch (magic[0]) {
		case '5':
			b64_from_24bit(buf[0], buf[10], buf[20], 4);
			b64_from_24bit(buf[21], buf[1], buf[11], 4);
			b64_from_24bit(buf[12], buf[22], buf[2], 4);
			b64_from_24bit(buf[3], buf[13], buf[23], 4);
			b64_from_24bit(buf[24], buf[4], buf[14], 4);
			b64_from_24bit(buf[15], buf[25], buf[5], 4);
			b64_from_24bit(buf[6], buf[16], buf[26], 4);
			b64_from_24bit(buf[27], buf[7], buf[17], 4);
			b64_from_24bit(buf[18], buf[28], buf[8], 4);
			b64_from_24bit(buf[9], buf[19], buf[29], 4);
			b64_from_24bit(0, buf[31], buf[30], 3);
			break;
		case '6':
			b64_from_24bit(buf[0], buf[21], buf[42], 4);
			b64_from_24bit(buf[22], buf[43], buf[1], 4);
			b64_from_24bit(buf[44], buf[2], buf[23], 4);
			b64_from_24bit(buf[3], buf[24], buf[45], 4);
			b64_from_24bit(buf[25], buf[46], buf[4], 4);
			b64_from_24bit(buf[47], buf[5], buf[26], 4);
			b64_from_24bit(buf[6], buf[27], buf[48], 4);
			b64_from_24bit(buf[28], buf[49], buf[7], 4);
			b64_from_24bit(buf[50], buf[8], buf[29], 4);
			b64_from_24bit(buf[9], buf[30], buf[51], 4);
			b64_from_24bit(buf[31], buf[52], buf[10], 4);
			b64_from_24bit(buf[53], buf[11], buf[32], 4);
			b64_from_24bit(buf[12], buf[33], buf[54], 4);
			b64_from_24bit(buf[34], buf[55], buf[13], 4);
			b64_from_24bit(buf[56], buf[14], buf[35], 4);
			b64_from_24bit(buf[15], buf[36], buf[57], 4);
			b64_from_24bit(buf[37], buf[58], buf[16], 4);
			b64_from_24bit(buf[59], buf[17], buf[38], 4);
			b64_from_24bit(buf[18], buf[39], buf[60], 4);
			b64_from_24bit(buf[40], buf[61], buf[19], 4);
			b64_from_24bit(buf[62], buf[20], buf[41], 4);
			b64_from_24bit(0, 0, buf[63], 2);
			break;
		default:
			goto err;
	}
	*cp = '\0';
#ifdef CHARSET_EBCDIC
	ascii2ebcdic(out_buf, out_buf, strlen(out_buf));
#endif

	return {out_buf};

err:
	EVP_MD_CTX_free(md2);
	EVP_MD_CTX_free(md);
	OPENSSL_free(p_bytes);
	OPENSSL_free(s_bytes);
	OPENSSL_free(ascii_passwd);

	return {};
}
#else
std::string shacrypt(const char*, const char*, const char*) { return {}; }
#endif
}  // namespace reindexer