xref: /freebsd/sys/crypto/via/padlock_hash.c (revision 1db64f89363c97858961c4df0b7d02f3223723cf)
1 /*-
2  * Copyright (c) 2006 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 
27 #include <sys/param.h>
28 #include <sys/systm.h>
29 #include <sys/kernel.h>
30 #include <sys/module.h>
31 #include <sys/malloc.h>
32 #include <sys/libkern.h>
33 #include <sys/endian.h>
34 #include <sys/pcpu.h>
35 #if defined(__amd64__) || defined(__i386__)
36 #include <machine/cpufunc.h>
37 #include <machine/cputypes.h>
38 #include <machine/fpu.h>
39 #include <machine/md_var.h>
40 #include <machine/specialreg.h>
41 #endif
42 #include <machine/pcb.h>
43 
44 #include <opencrypto/cryptodev.h>
45 #include <opencrypto/xform.h>
46 
47 #include <crypto/via/padlock.h>
48 
49 /*
50  * Implementation notes.
51  *
52  * Some VIA CPUs provides SHA1 and SHA256 acceleration.
53  * We implement all HMAC algorithms provided by crypto(9) framework, but we do
54  * the crypto work in software unless this is HMAC/SHA1 or HMAC/SHA256 and
55  * our CPU can accelerate it.
56  *
57  * Additional CPU instructions, which preform SHA1 and SHA256 are one-shot
58  * functions - we have only one chance to give the data, CPU itself will add
59  * the padding and calculate hash automatically.
60  * This means, it is not possible to implement common init(), update(), final()
61  * methods.
62  * The way I've choosen is to keep adding data to the buffer on update()
63  * (reallocating the buffer if necessary) and call XSHA{1,256} instruction on
64  * final().
65  */
66 
67 struct padlock_sha_ctx {
68 	uint8_t	*psc_buf;
69 	int	 psc_offset;
70 	int	 psc_size;
71 };
72 CTASSERT(sizeof(struct padlock_sha_ctx) <= sizeof(union authctx));
73 
74 static void padlock_sha_init(void *vctx);
75 static int padlock_sha_update(void *vctx, const void *buf, u_int bufsize);
76 static void padlock_sha1_final(uint8_t *hash, void *vctx);
77 static void padlock_sha256_final(uint8_t *hash, void *vctx);
78 
79 static const struct auth_hash padlock_hmac_sha1 = {
80 	.type = CRYPTO_SHA1_HMAC,
81 	.name = "HMAC-SHA1",
82 	.keysize = SHA1_BLOCK_LEN,
83 	.hashsize = SHA1_HASH_LEN,
84 	.ctxsize = sizeof(struct padlock_sha_ctx),
85 	.blocksize = SHA1_BLOCK_LEN,
86         .Init = padlock_sha_init,
87 	.Update = padlock_sha_update,
88 	.Final = padlock_sha1_final,
89 };
90 
91 static const struct auth_hash padlock_hmac_sha256 = {
92 	.type = CRYPTO_SHA2_256_HMAC,
93 	.name = "HMAC-SHA2-256",
94 	.keysize = SHA2_256_BLOCK_LEN,
95 	.hashsize = SHA2_256_HASH_LEN,
96 	.ctxsize = sizeof(struct padlock_sha_ctx),
97 	.blocksize = SHA2_256_BLOCK_LEN,
98         .Init = padlock_sha_init,
99 	.Update = padlock_sha_update,
100 	.Final = padlock_sha256_final,
101 };
102 
103 MALLOC_DECLARE(M_PADLOCK);
104 
105 static __inline void
106 padlock_output_block(uint32_t *src, uint32_t *dst, size_t count)
107 {
108 
109 	while (count-- > 0)
110 		*dst++ = bswap32(*src++);
111 }
112 
113 static void
114 padlock_do_sha1(const u_char *in, u_char *out, int count)
115 {
116 	u_char buf[128+16];	/* PadLock needs at least 128 bytes buffer. */
117 	u_char *result = PADLOCK_ALIGN(buf);
118 
119 	((uint32_t *)result)[0] = 0x67452301;
120 	((uint32_t *)result)[1] = 0xEFCDAB89;
121 	((uint32_t *)result)[2] = 0x98BADCFE;
122 	((uint32_t *)result)[3] = 0x10325476;
123 	((uint32_t *)result)[4] = 0xC3D2E1F0;
124 
125 	__asm __volatile(
126 		".byte  0xf3, 0x0f, 0xa6, 0xc8" /* rep xsha1 */
127 			: "+S"(in), "+D"(result)
128 			: "c"(count), "a"(0)
129 		);
130 
131 	padlock_output_block((uint32_t *)result, (uint32_t *)out,
132 	    SHA1_HASH_LEN / sizeof(uint32_t));
133 }
134 
135 static void
136 padlock_do_sha256(const char *in, char *out, int count)
137 {
138 	char buf[128+16];	/* PadLock needs at least 128 bytes buffer. */
139 	char *result = PADLOCK_ALIGN(buf);
140 
141 	((uint32_t *)result)[0] = 0x6A09E667;
142 	((uint32_t *)result)[1] = 0xBB67AE85;
143 	((uint32_t *)result)[2] = 0x3C6EF372;
144 	((uint32_t *)result)[3] = 0xA54FF53A;
145 	((uint32_t *)result)[4] = 0x510E527F;
146 	((uint32_t *)result)[5] = 0x9B05688C;
147 	((uint32_t *)result)[6] = 0x1F83D9AB;
148 	((uint32_t *)result)[7] = 0x5BE0CD19;
149 
150 	__asm __volatile(
151 		".byte  0xf3, 0x0f, 0xa6, 0xd0" /* rep xsha256 */
152 			: "+S"(in), "+D"(result)
153 			: "c"(count), "a"(0)
154 		);
155 
156 	padlock_output_block((uint32_t *)result, (uint32_t *)out,
157 	    SHA2_256_HASH_LEN / sizeof(uint32_t));
158 }
159 
160 static void
161 padlock_sha_init(void *vctx)
162 {
163 	struct padlock_sha_ctx *ctx;
164 
165 	ctx = vctx;
166 	ctx->psc_buf = NULL;
167 	ctx->psc_offset = 0;
168 	ctx->psc_size = 0;
169 }
170 
171 static int
172 padlock_sha_update(void *vctx, const void *buf, u_int bufsize)
173 {
174 	struct padlock_sha_ctx *ctx;
175 
176 	ctx = vctx;
177 	if (ctx->psc_size - ctx->psc_offset < bufsize) {
178 		ctx->psc_size = MAX(ctx->psc_size * 2, ctx->psc_size + bufsize);
179 		ctx->psc_buf = realloc(ctx->psc_buf, ctx->psc_size, M_PADLOCK,
180 		    M_NOWAIT);
181 		if(ctx->psc_buf == NULL)
182 			return (ENOMEM);
183 	}
184 	bcopy(buf, ctx->psc_buf + ctx->psc_offset, bufsize);
185 	ctx->psc_offset += bufsize;
186 	return (0);
187 }
188 
189 static void
190 padlock_sha_free(void *vctx)
191 {
192 	struct padlock_sha_ctx *ctx;
193 
194 	ctx = vctx;
195 	if (ctx->psc_buf != NULL) {
196 		zfree(ctx->psc_buf, M_PADLOCK);
197 		ctx->psc_buf = NULL;
198 		ctx->psc_offset = 0;
199 		ctx->psc_size = 0;
200 	}
201 }
202 
203 static void
204 padlock_sha1_final(uint8_t *hash, void *vctx)
205 {
206 	struct padlock_sha_ctx *ctx;
207 
208 	ctx = vctx;
209 	padlock_do_sha1(ctx->psc_buf, hash, ctx->psc_offset);
210 	padlock_sha_free(ctx);
211 }
212 
213 static void
214 padlock_sha256_final(uint8_t *hash, void *vctx)
215 {
216 	struct padlock_sha_ctx *ctx;
217 
218 	ctx = vctx;
219 	padlock_do_sha256(ctx->psc_buf, hash, ctx->psc_offset);
220 	padlock_sha_free(ctx);
221 }
222 
223 static void
224 padlock_copy_ctx(const struct auth_hash *axf, void *sctx, void *dctx)
225 {
226 
227 	if ((via_feature_xcrypt & VIA_HAS_SHA) != 0 &&
228 	    (axf->type == CRYPTO_SHA1_HMAC ||
229 	     axf->type == CRYPTO_SHA2_256_HMAC)) {
230 		struct padlock_sha_ctx *spctx = sctx, *dpctx = dctx;
231 
232 		dpctx->psc_offset = spctx->psc_offset;
233 		dpctx->psc_size = spctx->psc_size;
234 		dpctx->psc_buf = malloc(dpctx->psc_size, M_PADLOCK, M_WAITOK);
235 		bcopy(spctx->psc_buf, dpctx->psc_buf, dpctx->psc_size);
236 	} else {
237 		bcopy(sctx, dctx, axf->ctxsize);
238 	}
239 }
240 
241 static void
242 padlock_free_ctx(const struct auth_hash *axf, void *ctx)
243 {
244 
245 	if ((via_feature_xcrypt & VIA_HAS_SHA) != 0 &&
246 	    (axf->type == CRYPTO_SHA1_HMAC ||
247 	     axf->type == CRYPTO_SHA2_256_HMAC)) {
248 		padlock_sha_free(ctx);
249 	}
250 }
251 
252 static void
253 padlock_hash_key_setup(struct padlock_session *ses, const uint8_t *key,
254     int klen)
255 {
256 	const struct auth_hash *axf;
257 
258 	axf = ses->ses_axf;
259 
260 	/*
261 	 * Try to free contexts before using them, because
262 	 * padlock_hash_key_setup() can be called twice - once from
263 	 * padlock_newsession() and again from padlock_process().
264 	 */
265 	padlock_free_ctx(axf, ses->ses_ictx);
266 	padlock_free_ctx(axf, ses->ses_octx);
267 
268 	hmac_init_ipad(axf, key, klen, ses->ses_ictx);
269 	hmac_init_opad(axf, key, klen, ses->ses_octx);
270 }
271 
272 /*
273  * Compute keyed-hash authenticator.
274  */
275 static int
276 padlock_authcompute(struct padlock_session *ses, struct cryptop *crp)
277 {
278 	u_char hash[HASH_MAX_LEN], hash2[HASH_MAX_LEN];
279 	const struct auth_hash *axf;
280 	union authctx ctx;
281 	int error;
282 
283 	axf = ses->ses_axf;
284 
285 	padlock_copy_ctx(axf, ses->ses_ictx, &ctx);
286 	error = crypto_apply(crp, crp->crp_aad_start, crp->crp_aad_length,
287 	    axf->Update, &ctx);
288 	if (error != 0) {
289 		padlock_free_ctx(axf, &ctx);
290 		return (error);
291 	}
292 	error = crypto_apply(crp, crp->crp_payload_start,
293 	    crp->crp_payload_length, axf->Update, &ctx);
294 	if (error != 0) {
295 		padlock_free_ctx(axf, &ctx);
296 		return (error);
297 	}
298 	axf->Final(hash, &ctx);
299 
300 	padlock_copy_ctx(axf, ses->ses_octx, &ctx);
301 	axf->Update(&ctx, hash, axf->hashsize);
302 	axf->Final(hash, &ctx);
303 
304 	if (crp->crp_op & CRYPTO_OP_VERIFY_DIGEST) {
305 		crypto_copydata(crp, crp->crp_digest_start, ses->ses_mlen,
306 		    hash2);
307 		if (timingsafe_bcmp(hash, hash2, ses->ses_mlen) != 0)
308 			return (EBADMSG);
309 	} else
310 		crypto_copyback(crp, crp->crp_digest_start, ses->ses_mlen,
311 		    hash);
312 	return (0);
313 }
314 
315 /* Find software structure which describes HMAC algorithm. */
316 static const struct auth_hash *
317 padlock_hash_lookup(int alg)
318 {
319 	const struct auth_hash *axf;
320 
321 	switch (alg) {
322 	case CRYPTO_NULL_HMAC:
323 		axf = &auth_hash_null;
324 		break;
325 	case CRYPTO_SHA1_HMAC:
326 		if ((via_feature_xcrypt & VIA_HAS_SHA) != 0)
327 			axf = &padlock_hmac_sha1;
328 		else
329 			axf = &auth_hash_hmac_sha1;
330 		break;
331 	case CRYPTO_RIPEMD160_HMAC:
332 		axf = &auth_hash_hmac_ripemd_160;
333 		break;
334 	case CRYPTO_SHA2_256_HMAC:
335 		if ((via_feature_xcrypt & VIA_HAS_SHA) != 0)
336 			axf = &padlock_hmac_sha256;
337 		else
338 			axf = &auth_hash_hmac_sha2_256;
339 		break;
340 	case CRYPTO_SHA2_384_HMAC:
341 		axf = &auth_hash_hmac_sha2_384;
342 		break;
343 	case CRYPTO_SHA2_512_HMAC:
344 		axf = &auth_hash_hmac_sha2_512;
345 		break;
346 	default:
347 		axf = NULL;
348 		break;
349 	}
350 	return (axf);
351 }
352 
353 bool
354 padlock_hash_check(const struct crypto_session_params *csp)
355 {
356 
357 	return (padlock_hash_lookup(csp->csp_auth_alg) != NULL);
358 }
359 
360 int
361 padlock_hash_setup(struct padlock_session *ses,
362     const struct crypto_session_params *csp)
363 {
364 
365 	ses->ses_axf = padlock_hash_lookup(csp->csp_auth_alg);
366 	if (csp->csp_auth_mlen == 0)
367 		ses->ses_mlen = ses->ses_axf->hashsize;
368 	else
369 		ses->ses_mlen = csp->csp_auth_mlen;
370 
371 	/* Allocate memory for HMAC inner and outer contexts. */
372 	ses->ses_ictx = malloc(ses->ses_axf->ctxsize, M_PADLOCK,
373 	    M_ZERO | M_NOWAIT);
374 	ses->ses_octx = malloc(ses->ses_axf->ctxsize, M_PADLOCK,
375 	    M_ZERO | M_NOWAIT);
376 	if (ses->ses_ictx == NULL || ses->ses_octx == NULL)
377 		return (ENOMEM);
378 
379 	/* Setup key if given. */
380 	if (csp->csp_auth_key != NULL) {
381 		padlock_hash_key_setup(ses, csp->csp_auth_key,
382 		    csp->csp_auth_klen);
383 	}
384 	return (0);
385 }
386 
387 int
388 padlock_hash_process(struct padlock_session *ses, struct cryptop *crp,
389     const struct crypto_session_params *csp)
390 {
391 	struct thread *td;
392 	int error;
393 
394 	td = curthread;
395 	fpu_kern_enter(td, NULL, FPU_KERN_NORMAL | FPU_KERN_NOCTX);
396 	if (crp->crp_auth_key != NULL)
397 		padlock_hash_key_setup(ses, crp->crp_auth_key,
398 		    csp->csp_auth_klen);
399 
400 	error = padlock_authcompute(ses, crp);
401 	fpu_kern_leave(td, NULL);
402 	return (error);
403 }
404 
405 void
406 padlock_hash_free(struct padlock_session *ses)
407 {
408 
409 	if (ses->ses_ictx != NULL) {
410 		padlock_free_ctx(ses->ses_axf, ses->ses_ictx);
411 		zfree(ses->ses_ictx, M_PADLOCK);
412 		ses->ses_ictx = NULL;
413 	}
414 	if (ses->ses_octx != NULL) {
415 		padlock_free_ctx(ses->ses_axf, ses->ses_octx);
416 		zfree(ses->ses_octx, M_PADLOCK);
417 		ses->ses_octx = NULL;
418 	}
419 }
420