1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2011 Pawel Jakub Dawidek <pawel@dawidek.net>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30#include <errno.h>
31#include <string.h>
32#include <strings.h>
33
34#include <hast.h>
35#include <nv.h>
36#include <sha256.h>
37#include <zlib.h>
38#include <pjdlog.h>
39
40#include "hast_checksum.h"
41
42#define	MAX_HASH_SIZE	SHA256_DIGEST_LENGTH
43
44static void
45hast_crc32_checksum(const unsigned char *data, size_t size,
46    unsigned char *hash, size_t *hsizep)
47{
48	uint32_t crc;
49
50	crc = crc32(0L, Z_NULL, 0);
51	crc = crc32(crc, data, size);
52
53	/* XXXPJD: Do we have to use htole32() on crc first? */
54	bcopy(&crc, hash, sizeof(crc));
55	*hsizep = sizeof(crc);
56}
57
58static void
59hast_sha256_checksum(const unsigned char *data, size_t size,
60    unsigned char *hash, size_t *hsizep)
61{
62	SHA256_CTX ctx;
63
64	SHA256_Init(&ctx);
65	SHA256_Update(&ctx, data, size);
66	SHA256_Final(hash, &ctx);
67	*hsizep = SHA256_DIGEST_LENGTH;
68}
69
70const char *
71checksum_name(int num)
72{
73
74	switch (num) {
75	case HAST_CHECKSUM_NONE:
76		return ("none");
77	case HAST_CHECKSUM_CRC32:
78		return ("crc32");
79	case HAST_CHECKSUM_SHA256:
80		return ("sha256");
81	}
82	return ("unknown");
83}
84
85int
86checksum_send(const struct hast_resource *res, struct nv *nv, void **datap,
87    size_t *sizep, bool *freedatap __unused)
88{
89	unsigned char hash[MAX_HASH_SIZE];
90	size_t hsize;
91
92	switch (res->hr_checksum) {
93	case HAST_CHECKSUM_NONE:
94		return (0);
95	case HAST_CHECKSUM_CRC32:
96		hast_crc32_checksum(*datap, *sizep, hash, &hsize);
97		break;
98	case HAST_CHECKSUM_SHA256:
99		hast_sha256_checksum(*datap, *sizep, hash, &hsize);
100		break;
101	default:
102		PJDLOG_ABORT("Invalid checksum: %d.", res->hr_checksum);
103	}
104	nv_add_string(nv, checksum_name(res->hr_checksum), "checksum");
105	nv_add_uint8_array(nv, hash, hsize, "hash");
106	if (nv_error(nv) != 0) {
107		errno = nv_error(nv);
108		return (-1);
109	}
110	return (0);
111}
112
113int
114checksum_recv(const struct hast_resource *res __unused, struct nv *nv,
115    void **datap, size_t *sizep, bool *freedatap __unused)
116{
117	unsigned char chash[MAX_HASH_SIZE];
118	const unsigned char *rhash;
119	size_t chsize, rhsize;
120	const char *algo;
121
122	algo = nv_get_string(nv, "checksum");
123	if (algo == NULL)
124		return (0);	/* No checksum. */
125	rhash = nv_get_uint8_array(nv, &rhsize, "hash");
126	if (rhash == NULL) {
127		pjdlog_error("Hash is missing.");
128		return (-1);	/* Hash not found. */
129	}
130	if (strcmp(algo, "crc32") == 0)
131		hast_crc32_checksum(*datap, *sizep, chash, &chsize);
132	else if (strcmp(algo, "sha256") == 0)
133		hast_sha256_checksum(*datap, *sizep, chash, &chsize);
134	else {
135		pjdlog_error("Unknown checksum algorithm '%s'.", algo);
136		return (-1);	/* Unknown checksum algorithm. */
137	}
138	if (rhsize != chsize) {
139		pjdlog_error("Invalid hash size (%zu) for %s, should be %zu.",
140		    rhsize, algo, chsize);
141		return (-1);	/* Different hash size. */
142	}
143	if (bcmp(rhash, chash, chsize) != 0) {
144		pjdlog_error("Hash mismatch.");
145		return (-1);	/* Hash mismatch. */
146	}
147
148	return (0);
149}
150