xref: /freebsd/sys/geom/eli/g_eli.h (revision 87569f75a91f298c52a71823c04d41cf53c88889)
1 /*-
2  * Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #ifndef	_G_ELI_H_
30 #define	_G_ELI_H_
31 
32 #include <sys/endian.h>
33 #include <sys/errno.h>
34 #include <sys/malloc.h>
35 #include <crypto/sha2/sha2.h>
36 #include <opencrypto/cryptodev.h>
37 #ifdef _KERNEL
38 #include <sys/bio.h>
39 #include <sys/libkern.h>
40 #include <geom/geom.h>
41 #else
42 #include <stdio.h>
43 #include <string.h>
44 #include <strings.h>
45 #endif
46 #ifndef _OpenSSL_
47 #include <sys/md5.h>
48 #endif
49 
50 #define	G_ELI_CLASS_NAME	"ELI"
51 #define	G_ELI_MAGIC		"GEOM::ELI"
52 #define	G_ELI_SUFFIX		".eli"
53 
54 /*
55  * Version history:
56  * 0 - Initial version number.
57  */
58 #define	G_ELI_VERSION		0
59 
60 /* Use random, onetime keys. */
61 #define	G_ELI_FLAG_ONETIME	0x00000001
62 /* Ask for the passphrase from the kernel, before mounting root. */
63 #define	G_ELI_FLAG_BOOT		0x00000002
64 /* Detach on last close, if we were open for writing. */
65 #define	G_ELI_FLAG_WO_DETACH	0x00000004
66 /* Detach on last close. */
67 #define	G_ELI_FLAG_RW_DETACH	0x00000008
68 /* Provider was open for writing. */
69 #define	G_ELI_FLAG_WOPEN	0x00010000
70 /* Destroy device. */
71 #define	G_ELI_FLAG_DESTROY	0x00020000
72 
73 #define	SHA512_MDLEN		64
74 
75 #define	G_ELI_MAXMKEYS		2
76 #define	G_ELI_MAXKEYLEN		64
77 #define	G_ELI_USERKEYLEN	G_ELI_MAXKEYLEN
78 #define	G_ELI_DATAKEYLEN	G_ELI_MAXKEYLEN
79 #define	G_ELI_IVKEYLEN		G_ELI_MAXKEYLEN
80 #define	G_ELI_SALTLEN		64
81 #define	G_ELI_DATAIVKEYLEN	(G_ELI_DATAKEYLEN + G_ELI_IVKEYLEN)
82 /* Data-Key, IV-Key, HMAC_SHA512(Derived-Key, Data-Key+IV-Key) */
83 #define	G_ELI_MKEYLEN		(G_ELI_DATAIVKEYLEN + SHA512_MDLEN)
84 
85 #ifdef _KERNEL
86 extern u_int g_eli_debug;
87 extern u_int g_eli_overwrites;
88 
89 #define	G_ELI_CRYPTO_HW		1
90 #define	G_ELI_CRYPTO_SW		2
91 
92 #define	G_ELI_DEBUG(lvl, ...)	do {					\
93 	if (g_eli_debug >= (lvl)) {					\
94 		printf("GEOM_ELI");					\
95 		if (g_eli_debug > 0)					\
96 			printf("[%u]", lvl);				\
97 		printf(": ");						\
98 		printf(__VA_ARGS__);					\
99 		printf("\n");						\
100 	}								\
101 } while (0)
102 #define	G_ELI_LOGREQ(lvl, bp, ...)	do {				\
103 	if (g_eli_debug >= (lvl)) {					\
104 		printf("GEOM_ELI");					\
105 		if (g_eli_debug > 0)					\
106 			printf("[%u]", lvl);				\
107 		printf(": ");						\
108 		printf(__VA_ARGS__);					\
109 		printf(" ");						\
110 		g_print_bio(bp);					\
111 		printf("\n");						\
112 	}								\
113 } while (0)
114 
115 struct g_eli_worker {
116 	struct g_eli_softc	*w_softc;
117 	struct proc		*w_proc;
118 	u_int			 w_number;
119 	uint64_t		 w_sid;
120 	LIST_ENTRY(g_eli_worker) w_next;
121 };
122 
123 struct g_eli_softc {
124 	struct g_geom	*sc_geom;
125 	u_int		 sc_crypto;
126 	uint8_t		 sc_datakey[G_ELI_DATAKEYLEN];
127 	uint8_t		 sc_ivkey[G_ELI_IVKEYLEN];
128 	SHA256_CTX	 sc_ivctx;
129 	u_int		 sc_algo;
130 	u_int		 sc_keylen;
131 	int		 sc_nkey;
132 	uint32_t	 sc_flags;
133 
134 	/* Only for software cryptography. */
135 	struct bio_queue_head sc_queue;
136 	struct mtx	 sc_queue_mtx;
137 	LIST_HEAD(, g_eli_worker) sc_workers;
138 };
139 #define	sc_name		 sc_geom->name
140 #endif	/* _KERNEL */
141 
142 struct g_eli_metadata {
143 	char		md_magic[16];	/* Magic value. */
144 	uint32_t	md_version;	/* Version number. */
145 	uint32_t	md_flags;	/* Additional flags. */
146 	uint16_t	md_algo;	/* Encryption algorithm. */
147 	uint16_t	md_keylen;	/* Key length. */
148 	uint64_t	md_provsize;	/* Provider's size. */
149 	uint32_t	md_sectorsize;	/* Sector size. */
150 	uint8_t		md_keys;	/* Available keys. */
151 	int32_t		md_iterations;	/* Number of iterations for PKCS#5v2. */
152 	uint8_t		md_salt[G_ELI_SALTLEN]; /* Salt. */
153 			/* Encrypted master key (IV-key, Data-key, HMAC). */
154 	uint8_t		md_mkeys[G_ELI_MAXMKEYS * G_ELI_MKEYLEN];
155 	u_char		md_hash[16];	/* MD5 hash. */
156 } __packed;
157 #ifndef _OpenSSL_
158 static __inline void
159 eli_metadata_encode(struct g_eli_metadata *md, u_char *data)
160 {
161 	MD5_CTX ctx;
162 	u_char *p;
163 
164 	p = data;
165 	bcopy(md->md_magic, p, sizeof(md->md_magic)); p += sizeof(md->md_magic);
166 	le32enc(p, md->md_version);	p += sizeof(md->md_version);
167 	le32enc(p, md->md_flags);	p += sizeof(md->md_flags);
168 	le16enc(p, md->md_algo);	p += sizeof(md->md_algo);
169 	le16enc(p, md->md_keylen);	p += sizeof(md->md_keylen);
170 	le64enc(p, md->md_provsize);	p += sizeof(md->md_provsize);
171 	le32enc(p, md->md_sectorsize);	p += sizeof(md->md_sectorsize);
172 	*p = md->md_keys;		p += sizeof(md->md_keys);
173 	le32enc(p, md->md_iterations);	p += sizeof(md->md_iterations);
174 	bcopy(md->md_salt, p, sizeof(md->md_salt)); p += sizeof(md->md_salt);
175 	bcopy(md->md_mkeys, p, sizeof(md->md_mkeys)); p += sizeof(md->md_mkeys);
176 	MD5Init(&ctx);
177 	MD5Update(&ctx, data, p - data);
178 	MD5Final(md->md_hash, &ctx);
179 	bcopy(md->md_hash, p, sizeof(md->md_hash));
180 }
181 static __inline int
182 eli_metadata_decode_v0(const u_char *data, struct g_eli_metadata *md)
183 {
184 	MD5_CTX ctx;
185 	const u_char *p;
186 
187 	p = data + sizeof(md->md_magic) + sizeof(md->md_version);
188 	md->md_flags = le32dec(p);	p += sizeof(md->md_flags);
189 	md->md_algo = le16dec(p);	p += sizeof(md->md_algo);
190 	md->md_keylen = le16dec(p);	p += sizeof(md->md_keylen);
191 	md->md_provsize = le64dec(p);	p += sizeof(md->md_provsize);
192 	md->md_sectorsize = le32dec(p);	p += sizeof(md->md_sectorsize);
193 	md->md_keys = *p;		p += sizeof(md->md_keys);
194 	md->md_iterations = le32dec(p);	p += sizeof(md->md_iterations);
195 	bcopy(p, md->md_salt, sizeof(md->md_salt)); p += sizeof(md->md_salt);
196 	bcopy(p, md->md_mkeys, sizeof(md->md_mkeys)); p += sizeof(md->md_mkeys);
197 	MD5Init(&ctx);
198 	MD5Update(&ctx, data, p - data);
199 	MD5Final(md->md_hash, &ctx);
200 	if (bcmp(md->md_hash, p, 16) != 0)
201 		return (EINVAL);
202 	return (0);
203 }
204 static __inline int
205 eli_metadata_decode(const u_char *data, struct g_eli_metadata *md)
206 {
207 	int error;
208 
209 	bcopy(data, md->md_magic, sizeof(md->md_magic));
210 	md->md_version = le32dec(data + sizeof(md->md_magic));
211 	switch (md->md_version) {
212 	case 0:
213 		error = eli_metadata_decode_v0(data, md);
214 		break;
215 	default:
216 		error = EINVAL;
217 		break;
218 	}
219 	return (error);
220 }
221 #endif	/* !_OpenSSL */
222 
223 static __inline u_int
224 g_eli_str2algo(const char *name)
225 {
226 
227 	if (strcasecmp("null", name) == 0)
228 		return (CRYPTO_NULL_CBC);
229 	else if (strcasecmp("aes", name) == 0)
230 		return (CRYPTO_AES_CBC);
231 	else if (strcasecmp("blowfish", name) == 0)
232 		return (CRYPTO_BLF_CBC);
233 	else if (strcasecmp("3des", name) == 0)
234 		return (CRYPTO_3DES_CBC);
235 	return (CRYPTO_ALGORITHM_MIN - 1);
236 }
237 
238 static __inline const char *
239 g_eli_algo2str(u_int algo)
240 {
241 
242 	switch (algo) {
243 	case CRYPTO_NULL_CBC:
244 		return ("NULL");
245 	case CRYPTO_AES_CBC:
246 		return ("AES");
247 	case CRYPTO_BLF_CBC:
248 		return ("Blowfish");
249 	case CRYPTO_3DES_CBC:
250 		return ("3DES");
251 	}
252 	return ("unknown");
253 }
254 
255 static __inline void
256 eli_metadata_dump(const struct g_eli_metadata *md)
257 {
258 	static const char hex[] = "0123456789abcdef";
259 	char str[sizeof(md->md_mkeys) * 2 + 1];
260 	u_int i;
261 
262 	printf("     magic: %s\n", md->md_magic);
263 	printf("   version: %u\n", (u_int)md->md_version);
264 	printf("     flags: 0x%x\n", (u_int)md->md_flags);
265 	printf("      algo: %s\n", g_eli_algo2str(md->md_algo));
266 	printf("    keylen: %u\n", (u_int)md->md_keylen);
267 	printf("  provsize: %ju\n", (uintmax_t)md->md_provsize);
268 	printf("sectorsize: %u\n", (u_int)md->md_sectorsize);
269 	printf("      keys: 0x%02x\n", (u_int)md->md_keys);
270 	printf("iterations: %u\n", (u_int)md->md_iterations);
271 	bzero(str, sizeof(str));
272 	for (i = 0; i < sizeof(md->md_salt); i++) {
273 		str[i * 2] = hex[md->md_salt[i] >> 4];
274 		str[i * 2 + 1] = hex[md->md_salt[i] & 0x0f];
275 	}
276 	printf("      Salt: %s\n", str);
277 	bzero(str, sizeof(str));
278 	for (i = 0; i < sizeof(md->md_mkeys); i++) {
279 		str[i * 2] = hex[md->md_mkeys[i] >> 4];
280 		str[i * 2 + 1] = hex[md->md_mkeys[i] & 0x0f];
281 	}
282 	printf("Master Key: %s\n", str);
283 	bzero(str, sizeof(str));
284 	for (i = 0; i < 16; i++) {
285 		str[i * 2] = hex[md->md_hash[i] >> 4];
286 		str[i * 2 + 1] = hex[md->md_hash[i] & 0x0f];
287 	}
288 	printf("  MD5 hash: %s\n", str);
289 }
290 
291 static __inline u_int
292 g_eli_keylen(u_int algo, u_int keylen)
293 {
294 
295 	switch (algo) {
296 	case CRYPTO_NULL_CBC:
297 		if (keylen == 0)
298 			keylen = 64 * 8;
299 		else {
300 			if (keylen > 64 * 8)
301 				keylen = 0;
302 		}
303 		return (keylen);
304 	case CRYPTO_AES_CBC:
305 		switch (keylen) {
306 		case 0:
307 			return (128);
308 		case 128:
309 		case 192:
310 		case 256:
311 			return (keylen);
312 		default:
313 			return (0);
314 		}
315 	case CRYPTO_BLF_CBC:
316 		if (keylen == 0)
317 			return (128);
318 		if (keylen < 128 || keylen > 448)
319 			return (0);
320 		if ((keylen % 32) != 0)
321 			return (0);
322 		return (keylen);
323 	case CRYPTO_3DES_CBC:
324 		if (keylen == 0 || keylen == 192)
325 			return (192);
326 		return (0);
327 	default:
328 		return (0);
329 	}
330 }
331 
332 #ifdef _KERNEL
333 int g_eli_read_metadata(struct g_class *mp, struct g_provider *pp,
334     struct g_eli_metadata *md);
335 struct g_geom *g_eli_create(struct gctl_req *req, struct g_class *mp,
336     struct g_provider *bpp, const struct g_eli_metadata *md,
337     const u_char *mkey, int nkey);
338 int g_eli_destroy(struct g_eli_softc *sc, boolean_t force);
339 
340 int g_eli_access(struct g_provider *pp, int dr, int dw, int de);
341 void g_eli_config(struct gctl_req *req, struct g_class *mp, const char *verb);
342 #endif
343 
344 void g_eli_mkey_hmac(unsigned char *mkey, const unsigned char *key);
345 int g_eli_mkey_decrypt(const struct g_eli_metadata *md,
346     const unsigned char *key, unsigned char *mkey, unsigned *nkeyp);
347 int g_eli_mkey_encrypt(unsigned algo, const unsigned char *key, unsigned keylen,
348     unsigned char *mkey);
349 
350 int g_eli_crypto_encrypt(u_int algo, u_char *data, size_t datasize,
351     const u_char *key, size_t keysize);
352 int g_eli_crypto_decrypt(u_int algo, u_char *data, size_t datasize,
353     const u_char *key, size_t keysize);
354 
355 struct hmac_ctx {
356 	SHA512_CTX	shactx;
357 	u_char		k_opad[128];
358 };
359 
360 void g_eli_crypto_hmac_init(struct hmac_ctx *ctx, const uint8_t *hkey,
361     size_t hkeylen);
362 void g_eli_crypto_hmac_update(struct hmac_ctx *ctx, const uint8_t *data,
363     size_t datasize);
364 void g_eli_crypto_hmac_final(struct hmac_ctx *ctx, uint8_t *md, size_t mdsize);
365 void g_eli_crypto_hmac(const uint8_t *hkey, size_t hkeysize,
366     const uint8_t *data, size_t datasize, uint8_t *md, size_t mdsize);
367 #endif	/* !_G_ELI_H_ */
368