xref: /titanic_41/usr/src/uts/common/crypto/io/arcfour.c (revision 6d24d8e5e4f6a2d14992d9392981d8a16d695aec)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * RC4 provider for the Kernel Cryptographic Framework (KCF)
28  */
29 
30 #include <sys/types.h>
31 #include <sys/systm.h>
32 #include <sys/modctl.h>
33 #include <sys/cmn_err.h>
34 #include <sys/ddi.h>
35 #include <sys/crypto/common.h>
36 #include <sys/crypto/spi.h>
37 #include <sys/sysmacros.h>
38 #include <sys/strsun.h>
39 #include <arcfour.h>
40 
41 extern struct mod_ops mod_cryptoops;
42 
43 /*
44  * Module linkage information for the kernel.
45  */
46 static struct modlcrypto modlcrypto = {
47 	&mod_cryptoops,
48 	"RC4 Kernel SW Provider"
49 };
50 
51 static struct modlinkage modlinkage = {
52 	MODREV_1,
53 	(void *)&modlcrypto,
54 	NULL
55 };
56 
57 /*
58  * CSPI information (entry points, provider info, etc.)
59  */
60 
61 #define	RC4_MECH_INFO_TYPE	0
62 /*
63  * Mechanism info structure passed to KCF during registration.
64  */
65 static crypto_mech_info_t rc4_mech_info_tab[] = {
66 	{SUN_CKM_RC4, RC4_MECH_INFO_TYPE,
67 	    CRYPTO_FG_ENCRYPT | CRYPTO_FG_ENCRYPT_ATOMIC |
68 	    CRYPTO_FG_DECRYPT | CRYPTO_FG_DECRYPT_ATOMIC,
69 	    ARCFOUR_MIN_KEY_BITS, ARCFOUR_MAX_KEY_BITS,
70 	    CRYPTO_KEYSIZE_UNIT_IN_BITS | CRYPTO_CAN_SHARE_OPSTATE}
71 };
72 
73 static void rc4_provider_status(crypto_provider_handle_t, uint_t *);
74 
75 static crypto_control_ops_t rc4_control_ops = {
76 	rc4_provider_status
77 };
78 
79 static int rc4_common_init(crypto_ctx_t *, crypto_mechanism_t *,
80     crypto_key_t *, crypto_spi_ctx_template_t, crypto_req_handle_t);
81 
82 static int rc4_crypt_update(crypto_ctx_t *, crypto_data_t *, crypto_data_t *,
83     crypto_req_handle_t);
84 
85 static int rc4_crypt_final(crypto_ctx_t *, crypto_data_t *,
86     crypto_req_handle_t);
87 
88 static int rc4_crypt(crypto_ctx_t *, crypto_data_t *, crypto_data_t *,
89     crypto_req_handle_t);
90 
91 static int rc4_crypt_atomic(crypto_provider_handle_t, crypto_session_id_t,
92     crypto_mechanism_t *, crypto_key_t *, crypto_data_t *,
93     crypto_data_t *, crypto_spi_ctx_template_t, crypto_req_handle_t);
94 
95 
96 static crypto_cipher_ops_t rc4_cipher_ops = {
97 	rc4_common_init,
98 	rc4_crypt,
99 	rc4_crypt_update,
100 	rc4_crypt_final,
101 	rc4_crypt_atomic,
102 	rc4_common_init,
103 	rc4_crypt,
104 	rc4_crypt_update,
105 	rc4_crypt_final,
106 	rc4_crypt_atomic
107 };
108 
109 static int rc4_free_context(crypto_ctx_t *);
110 
111 static crypto_ctx_ops_t rc4_ctx_ops = {
112 	NULL,
113 	rc4_free_context
114 };
115 
116 static crypto_ops_t rc4_crypto_ops = {
117 	&rc4_control_ops,
118 	NULL,
119 	&rc4_cipher_ops,
120 	NULL,
121 	NULL,
122 	NULL,
123 	NULL,
124 	NULL,
125 	NULL,
126 	NULL,
127 	NULL,
128 	NULL,
129 	NULL,
130 	&rc4_ctx_ops
131 };
132 
133 static crypto_provider_info_t rc4_prov_info = {
134 	CRYPTO_SPI_VERSION_1,
135 	"RC4 Software Provider",
136 	CRYPTO_SW_PROVIDER,
137 	{&modlinkage},
138 	NULL,
139 	&rc4_crypto_ops,
140 	sizeof (rc4_mech_info_tab)/sizeof (crypto_mech_info_t),
141 	rc4_mech_info_tab
142 };
143 
144 static crypto_kcf_provider_handle_t rc4_prov_handle = NULL;
145 
146 static mblk_t *advance_position(mblk_t *, off_t, uchar_t **);
147 static int crypto_arcfour_crypt(ARCFour_key *, uchar_t *, crypto_data_t *,
148     int);
149 
150 int
151 _init(void)
152 {
153 	int ret;
154 
155 	if ((ret = mod_install(&modlinkage)) != 0)
156 		return (ret);
157 
158 	/* Register with KCF.  If the registration fails, remove the module. */
159 	if (crypto_register_provider(&rc4_prov_info, &rc4_prov_handle)) {
160 		(void) mod_remove(&modlinkage);
161 		return (EACCES);
162 	}
163 
164 	return (0);
165 }
166 
167 int
168 _fini(void)
169 {
170 	/* Unregister from KCF if module is registered */
171 	if (rc4_prov_handle != NULL) {
172 		if (crypto_unregister_provider(rc4_prov_handle))
173 			return (EBUSY);
174 
175 		rc4_prov_handle = NULL;
176 	}
177 
178 	return (mod_remove(&modlinkage));
179 }
180 
181 int
182 _info(struct modinfo *modinfop)
183 {
184 	return (mod_info(&modlinkage, modinfop));
185 }
186 
187 
188 /*
189  * KCF software provider control entry points.
190  */
191 /* ARGSUSED */
192 static void
193 rc4_provider_status(crypto_provider_handle_t provider, uint_t *status)
194 {
195 	*status = CRYPTO_PROVIDER_READY;
196 }
197 
198 /* ARGSUSED */
199 static int
200 rc4_common_init(crypto_ctx_t *ctx, crypto_mechanism_t *mechanism,
201     crypto_key_t *key, crypto_spi_ctx_template_t template,
202     crypto_req_handle_t req)
203 {
204 	ARCFour_key *keystream;
205 
206 	if ((mechanism)->cm_type != RC4_MECH_INFO_TYPE)
207 		return (CRYPTO_MECHANISM_INVALID);
208 
209 	if (key->ck_format != CRYPTO_KEY_RAW)
210 		return (CRYPTO_KEY_TYPE_INCONSISTENT);
211 
212 	if (key->ck_length < ARCFOUR_MIN_KEY_BITS ||
213 	    key->ck_length > ARCFOUR_MAX_KEY_BITS) {
214 		return (CRYPTO_KEY_SIZE_RANGE);
215 	}
216 
217 	/*
218 	 * Allocate an RC4 key stream.
219 	 */
220 	if ((keystream = kmem_alloc(sizeof (ARCFour_key),
221 	    crypto_kmflag(req))) == NULL)
222 		return (CRYPTO_HOST_MEMORY);
223 
224 	arcfour_key_init(keystream, key->ck_data,
225 	    CRYPTO_BITS2BYTES(key->ck_length));
226 
227 	ctx->cc_provider_private = keystream;
228 
229 	return (CRYPTO_SUCCESS);
230 }
231 
232 static int
233 rc4_crypt(crypto_ctx_t *ctx, crypto_data_t *input, crypto_data_t *output,
234     crypto_req_handle_t req)
235 {
236 	int ret;
237 
238 	ret = rc4_crypt_update(ctx, input, output, req);
239 
240 	if (ret != CRYPTO_BUFFER_TOO_SMALL)
241 		(void) rc4_free_context(ctx);
242 
243 	return (ret);
244 }
245 
246 /* ARGSUSED */
247 static int
248 rc4_crypt_update(crypto_ctx_t *ctx, crypto_data_t *input, crypto_data_t *output,
249     crypto_req_handle_t req)
250 {
251 	int ret = CRYPTO_SUCCESS;
252 
253 	ARCFour_key *key;
254 	off_t saveoffset;
255 
256 	ASSERT(ctx->cc_provider_private != NULL);
257 
258 	if ((ctx->cc_flags & CRYPTO_USE_OPSTATE) && ctx->cc_opstate != NULL)
259 		key = ctx->cc_opstate;
260 	else
261 		key = ctx->cc_provider_private;
262 
263 	/* Simple case: in-line encipherment */
264 
265 	if (output == NULL) {
266 		switch (input->cd_format) {
267 		case CRYPTO_DATA_RAW: {
268 			char *start, *end;
269 			start = input->cd_raw.iov_base + input->cd_offset;
270 
271 			end =  input->cd_raw.iov_base + input->cd_raw.iov_len;
272 
273 			if (start + input->cd_length > end)
274 				return (CRYPTO_DATA_INVALID);
275 
276 			arcfour_crypt(key, (uchar_t *)start, (uchar_t *)start,
277 			    input->cd_length);
278 			break;
279 		}
280 		case CRYPTO_DATA_MBLK: {
281 			uchar_t *start, *end;
282 			size_t len, left;
283 			mblk_t *mp = input->cd_mp, *mp1, *mp2;
284 
285 			ASSERT(mp != NULL);
286 
287 			mp1 = advance_position(mp, input->cd_offset, &start);
288 
289 			if (mp1 == NULL)
290 				return (CRYPTO_DATA_LEN_RANGE);
291 
292 			mp2 = advance_position(mp, input->cd_offset +
293 			    input->cd_length, &end);
294 
295 			if (mp2 == NULL)
296 				return (CRYPTO_DATA_LEN_RANGE);
297 
298 			left = input->cd_length;
299 			while (mp1 != NULL) {
300 				if (_PTRDIFF(mp1->b_wptr, start) > left) {
301 					len = left;
302 					arcfour_crypt(key, start, start, len);
303 					mp1 = NULL;
304 				} else {
305 					len = _PTRDIFF(mp1->b_wptr, start);
306 					arcfour_crypt(key, start, start, len);
307 					mp1 = mp1->b_cont;
308 					start = mp1->b_rptr;
309 					left -= len;
310 				}
311 			}
312 			break;
313 		}
314 		case CRYPTO_DATA_UIO: {
315 			uio_t *uiop = input->cd_uio;
316 			off_t offset = input->cd_offset;
317 			size_t length = input->cd_length;
318 			uint_t vec_idx;
319 			size_t cur_len;
320 
321 			/*
322 			 * Jump to the first iovec containing data to be
323 			 * processed.
324 			 */
325 			for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
326 			    offset >= uiop->uio_iov[vec_idx].iov_len;
327 			    offset -= uiop->uio_iov[vec_idx++].iov_len)
328 				;
329 			if (vec_idx == uiop->uio_iovcnt) {
330 				return (CRYPTO_DATA_LEN_RANGE);
331 			}
332 
333 			/*
334 			 * Now process the iovecs.
335 			 */
336 			while (vec_idx < uiop->uio_iovcnt && length > 0) {
337 				uchar_t *start;
338 				iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
339 
340 				cur_len = MIN(iovp->iov_len - offset, length);
341 
342 				start = (uchar_t *)(iovp->iov_base + offset);
343 				arcfour_crypt(key, start + offset,
344 				    start + offset, cur_len);
345 
346 				length -= cur_len;
347 				vec_idx++;
348 				offset = 0;
349 			}
350 
351 			if (vec_idx == uiop->uio_iovcnt && length > 0) {
352 
353 				return (CRYPTO_DATA_LEN_RANGE);
354 			}
355 			break;
356 		}
357 		}
358 		return (CRYPTO_SUCCESS);
359 	}
360 
361 	/*
362 	 * We need to just return the length needed to store the output.
363 	 * We should not destroy the context for the following case.
364 	 */
365 
366 	if (input->cd_length > output->cd_length) {
367 		output->cd_length = input->cd_length;
368 		return (CRYPTO_BUFFER_TOO_SMALL);
369 	}
370 
371 	saveoffset = output->cd_offset;
372 
373 	switch (input->cd_format) {
374 	case CRYPTO_DATA_RAW: {
375 		char *start, *end;
376 		start = input->cd_raw.iov_base + input->cd_offset;
377 
378 		end =  input->cd_raw.iov_base + input->cd_raw.iov_len;
379 
380 		if (start + input->cd_length > end)
381 			return (CRYPTO_DATA_LEN_RANGE);
382 
383 		ret = crypto_arcfour_crypt(key, (uchar_t *)start, output,
384 		    input->cd_length);
385 
386 		if (ret != CRYPTO_SUCCESS)
387 			return (ret);
388 		break;
389 	}
390 	case CRYPTO_DATA_MBLK: {
391 		uchar_t *start, *end;
392 		size_t len, left;
393 		mblk_t *mp = input->cd_mp, *mp1, *mp2;
394 
395 		ASSERT(mp != NULL);
396 
397 		mp1 = advance_position(mp, input->cd_offset, &start);
398 
399 		if (mp1 == NULL)
400 			return (CRYPTO_DATA_LEN_RANGE);
401 
402 		mp2 = advance_position(mp, input->cd_offset + input->cd_length,
403 		    &end);
404 
405 		if (mp2 == NULL)
406 			return (CRYPTO_DATA_LEN_RANGE);
407 
408 		left = input->cd_length;
409 		while (mp1 != NULL) {
410 			if (_PTRDIFF(mp1->b_wptr, start) > left) {
411 				len = left;
412 				ret = crypto_arcfour_crypt(key, start, output,
413 				    len);
414 				if (ret != CRYPTO_SUCCESS)
415 					return (ret);
416 				mp1 = NULL;
417 			} else {
418 				len = _PTRDIFF(mp1->b_wptr, start);
419 				ret = crypto_arcfour_crypt(key, start, output,
420 				    len);
421 				if (ret != CRYPTO_SUCCESS)
422 					return (ret);
423 				mp1 = mp1->b_cont;
424 				start = mp1->b_rptr;
425 				left -= len;
426 				output->cd_offset += len;
427 			}
428 		}
429 		break;
430 	}
431 	case CRYPTO_DATA_UIO: {
432 		uio_t *uiop = input->cd_uio;
433 		off_t offset = input->cd_offset;
434 		size_t length = input->cd_length;
435 		uint_t vec_idx;
436 		size_t cur_len;
437 
438 		/*
439 		 * Jump to the first iovec containing data to be
440 		 * processed.
441 		 */
442 		for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
443 		    offset >= uiop->uio_iov[vec_idx].iov_len;
444 		    offset -= uiop->uio_iov[vec_idx++].iov_len)
445 			;
446 		if (vec_idx == uiop->uio_iovcnt) {
447 			return (CRYPTO_DATA_LEN_RANGE);
448 		}
449 
450 		/*
451 		 * Now process the iovecs.
452 		 */
453 		while (vec_idx < uiop->uio_iovcnt && length > 0) {
454 			uchar_t *start;
455 			iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
456 			cur_len = MIN(iovp->iov_len - offset, length);
457 
458 			start = (uchar_t *)(iovp->iov_base + offset);
459 			ret = crypto_arcfour_crypt(key, start + offset,
460 			    output, cur_len);
461 			if (ret != CRYPTO_SUCCESS)
462 				return (ret);
463 
464 			length -= cur_len;
465 			vec_idx++;
466 			offset = 0;
467 			output->cd_offset += cur_len;
468 		}
469 
470 		if (vec_idx == uiop->uio_iovcnt && length > 0) {
471 
472 			return (CRYPTO_DATA_LEN_RANGE);
473 		}
474 	}
475 	}
476 
477 	output->cd_offset = saveoffset;
478 	output->cd_length = input->cd_length;
479 
480 	return (ret);
481 }
482 
483 /* ARGSUSED */
484 static int rc4_crypt_final(crypto_ctx_t *ctx, crypto_data_t *data,
485     crypto_req_handle_t req)
486 {
487 	/* No final part for streams ciphers. Just free the context */
488 	if (data != NULL)
489 		data->cd_length = 0;
490 
491 	return (rc4_free_context(ctx));
492 }
493 
494 /* ARGSUSED */
495 static int
496 rc4_crypt_atomic(crypto_provider_handle_t handle, crypto_session_id_t session,
497     crypto_mechanism_t *mechanism, crypto_key_t *key, crypto_data_t *input,
498     crypto_data_t *output, crypto_spi_ctx_template_t template,
499     crypto_req_handle_t req)
500 {
501 	crypto_ctx_t ctx;
502 	int ret;
503 
504 	bzero(&ctx, sizeof (crypto_ctx_t));
505 	ret = rc4_common_init(&ctx, mechanism, key, template, req);
506 
507 	if (ret != CRYPTO_SUCCESS)
508 		return (ret);
509 
510 	ret = rc4_crypt_update(&ctx, input, output, req);
511 
512 	(void) rc4_free_context(&ctx);
513 
514 	return (ret);
515 }
516 
517 /* ARGSUSED */
518 static int
519 rc4_free_context(crypto_ctx_t *ctx)
520 {
521 	ARCFour_key *keystream = ctx->cc_provider_private;
522 
523 	if (keystream != NULL) {
524 		bzero(keystream, sizeof (ARCFour_key));
525 		kmem_free(keystream, sizeof (ARCFour_key));
526 		ctx->cc_provider_private = NULL;
527 	}
528 
529 	return (CRYPTO_SUCCESS);
530 }
531 
532 /* Encrypts a contiguous input 'in' into the 'out' crypto_data_t */
533 
534 static int
535 crypto_arcfour_crypt(ARCFour_key *key, uchar_t *in, crypto_data_t *out,
536     int length)
537 {
538 	switch (out->cd_format) {
539 		case CRYPTO_DATA_RAW: {
540 			uchar_t *start, *end;
541 			start = (uchar_t *)(out->cd_raw.iov_base +
542 			    out->cd_offset);
543 
544 			end = (uchar_t *)(out->cd_raw.iov_base +
545 			    out->cd_raw.iov_len);
546 
547 			if (start + out->cd_length > end)
548 				return (CRYPTO_DATA_LEN_RANGE);
549 
550 			arcfour_crypt(key, in, start, length);
551 
552 			return (CRYPTO_SUCCESS);
553 		}
554 		case CRYPTO_DATA_MBLK: {
555 			uchar_t *start, *end;
556 			size_t len, left;
557 			mblk_t *mp = out->cd_mp, *mp1, *mp2;
558 
559 			ASSERT(mp != NULL);
560 
561 			mp1 = advance_position(mp, out->cd_offset, &start);
562 
563 			if (mp1 == NULL)
564 				return (CRYPTO_DATA_LEN_RANGE);
565 
566 			mp2 = advance_position(mp, out->cd_offset +
567 			    out->cd_length, &end);
568 
569 			if (mp2 == NULL)
570 				return (CRYPTO_DATA_LEN_RANGE);
571 
572 			left = length;
573 			while (mp1 != NULL) {
574 				if (_PTRDIFF(mp1->b_wptr, start) > left) {
575 					len = left;
576 					arcfour_crypt(key, in, start, len);
577 					mp1 = NULL;
578 				} else {
579 					len = _PTRDIFF(mp1->b_wptr, start);
580 					arcfour_crypt(key, in, start, len);
581 					mp1 = mp1->b_cont;
582 					start = mp1->b_rptr;
583 					left -= len;
584 				}
585 			}
586 			break;
587 		}
588 		case CRYPTO_DATA_UIO: {
589 			uio_t *uiop = out->cd_uio;
590 			off_t offset = out->cd_offset;
591 			size_t len = length;
592 			uint_t vec_idx;
593 			size_t cur_len;
594 
595 			/*
596 			 * Jump to the first iovec containing data to be
597 			 * processed.
598 			 */
599 			for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
600 			    offset >= uiop->uio_iov[vec_idx].iov_len;
601 			    offset -= uiop->uio_iov[vec_idx++].iov_len)
602 				;
603 			if (vec_idx == uiop->uio_iovcnt) {
604 				return (CRYPTO_DATA_LEN_RANGE);
605 			}
606 
607 			/*
608 			 * Now process the iovecs.
609 			 */
610 			while (vec_idx < uiop->uio_iovcnt && len > 0) {
611 				uchar_t *start;
612 				iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
613 				cur_len = MIN(iovp->iov_len - offset, len);
614 
615 				start = (uchar_t *)(iovp->iov_base + offset);
616 				arcfour_crypt(key, start + offset,
617 				    start + offset, cur_len);
618 
619 				len -= cur_len;
620 				vec_idx++;
621 				offset = 0;
622 			}
623 
624 			if (vec_idx == uiop->uio_iovcnt && len > 0) {
625 				return (CRYPTO_DATA_LEN_RANGE);
626 			}
627 			break;
628 		}
629 		default:
630 			return (CRYPTO_DATA_INVALID);
631 	}
632 	return (CRYPTO_SUCCESS);
633 }
634 
635 /*
636  * Advances 'offset' bytes from the beginning of the first block in 'mp',
637  * possibly jumping across b_cont boundary
638  * '*cpp' is set to the position of the byte we want, and the block where
639  * 'cpp' is returned.
640  */
641 static mblk_t *
642 advance_position(mblk_t *mp, off_t offset, uchar_t **cpp)
643 {
644 	mblk_t *mp1 = mp;
645 	size_t l;
646 	off_t o = offset;
647 
648 	while (mp1 != NULL) {
649 		l = MBLKL(mp1);
650 
651 		if (l <= o) {
652 			o -= l;
653 			mp1 = mp1->b_cont;
654 		} else {
655 			*cpp = (uchar_t *)(mp1->b_rptr + o);
656 			break;
657 		}
658 	}
659 	return (mp1);
660 }
661