xref: /titanic_41/usr/src/uts/common/crypto/io/arcfour.c (revision f6e214c7418f43af38bd8c3a557e3d0a1d311cfa)
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 
205 /* EXPORT DELETE START */
206 
207 	ARCFour_key *keystream;
208 
209 	if ((mechanism)->cm_type != RC4_MECH_INFO_TYPE)
210 		return (CRYPTO_MECHANISM_INVALID);
211 
212 	if (key->ck_format != CRYPTO_KEY_RAW)
213 		return (CRYPTO_KEY_TYPE_INCONSISTENT);
214 
215 	if (key->ck_length < ARCFOUR_MIN_KEY_BITS ||
216 	    key->ck_length > ARCFOUR_MAX_KEY_BITS) {
217 		return (CRYPTO_KEY_SIZE_RANGE);
218 	}
219 
220 	/*
221 	 * Allocate an RC4 key stream.
222 	 */
223 	if ((keystream = kmem_alloc(sizeof (ARCFour_key),
224 	    crypto_kmflag(req))) == NULL)
225 		return (CRYPTO_HOST_MEMORY);
226 
227 	arcfour_key_init(keystream, key->ck_data,
228 	    CRYPTO_BITS2BYTES(key->ck_length));
229 
230 	ctx->cc_provider_private = keystream;
231 
232 /* EXPORT DELETE END */
233 
234 	return (CRYPTO_SUCCESS);
235 }
236 
237 static int
238 rc4_crypt(crypto_ctx_t *ctx, crypto_data_t *input, crypto_data_t *output,
239     crypto_req_handle_t req)
240 {
241 	int ret;
242 
243 	ret = rc4_crypt_update(ctx, input, output, req);
244 
245 	if (ret != CRYPTO_BUFFER_TOO_SMALL)
246 		(void) rc4_free_context(ctx);
247 
248 	return (ret);
249 }
250 
251 /* ARGSUSED */
252 static int
253 rc4_crypt_update(crypto_ctx_t *ctx, crypto_data_t *input, crypto_data_t *output,
254     crypto_req_handle_t req)
255 {
256 	int ret = CRYPTO_SUCCESS;
257 
258 /* EXPORT DELETE START */
259 
260 	ARCFour_key *key;
261 	off_t saveoffset;
262 
263 	ASSERT(ctx->cc_provider_private != NULL);
264 
265 	if ((ctx->cc_flags & CRYPTO_USE_OPSTATE) && ctx->cc_opstate != NULL)
266 		key = ctx->cc_opstate;
267 	else
268 		key = ctx->cc_provider_private;
269 
270 	/* Simple case: in-line encipherment */
271 
272 	if (output == NULL) {
273 		switch (input->cd_format) {
274 		case CRYPTO_DATA_RAW: {
275 			char *start, *end;
276 			start = input->cd_raw.iov_base + input->cd_offset;
277 
278 			end =  input->cd_raw.iov_base + input->cd_raw.iov_len;
279 
280 			if (start + input->cd_length > end)
281 				return (CRYPTO_DATA_INVALID);
282 
283 			arcfour_crypt(key, (uchar_t *)start, (uchar_t *)start,
284 			    input->cd_length);
285 			break;
286 		}
287 		case CRYPTO_DATA_MBLK: {
288 			uchar_t *start, *end;
289 			size_t len, left;
290 			mblk_t *mp = input->cd_mp, *mp1, *mp2;
291 
292 			ASSERT(mp != NULL);
293 
294 			mp1 = advance_position(mp, input->cd_offset, &start);
295 
296 			if (mp1 == NULL)
297 				return (CRYPTO_DATA_LEN_RANGE);
298 
299 			mp2 = advance_position(mp, input->cd_offset +
300 			    input->cd_length, &end);
301 
302 			if (mp2 == NULL)
303 				return (CRYPTO_DATA_LEN_RANGE);
304 
305 			left = input->cd_length;
306 			while (mp1 != NULL) {
307 				if (_PTRDIFF(mp1->b_wptr, start) > left) {
308 					len = left;
309 					arcfour_crypt(key, start, start, len);
310 					mp1 = NULL;
311 				} else {
312 					len = _PTRDIFF(mp1->b_wptr, start);
313 					arcfour_crypt(key, start, start, len);
314 					mp1 = mp1->b_cont;
315 					start = mp1->b_rptr;
316 					left -= len;
317 				}
318 			}
319 			break;
320 		}
321 		case CRYPTO_DATA_UIO: {
322 			uio_t *uiop = input->cd_uio;
323 			off_t offset = input->cd_offset;
324 			size_t length = input->cd_length;
325 			uint_t vec_idx;
326 			size_t cur_len;
327 
328 			/*
329 			 * Jump to the first iovec containing data to be
330 			 * processed.
331 			 */
332 			for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
333 			    offset >= uiop->uio_iov[vec_idx].iov_len;
334 			    offset -= uiop->uio_iov[vec_idx++].iov_len)
335 				;
336 			if (vec_idx == uiop->uio_iovcnt) {
337 				return (CRYPTO_DATA_LEN_RANGE);
338 			}
339 
340 			/*
341 			 * Now process the iovecs.
342 			 */
343 			while (vec_idx < uiop->uio_iovcnt && length > 0) {
344 				uchar_t *start;
345 				iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
346 
347 				cur_len = MIN(iovp->iov_len - offset, length);
348 
349 				start = (uchar_t *)(iovp->iov_base + offset);
350 				arcfour_crypt(key, start + offset,
351 				    start + offset, cur_len);
352 
353 				length -= cur_len;
354 				vec_idx++;
355 				offset = 0;
356 			}
357 
358 			if (vec_idx == uiop->uio_iovcnt && length > 0) {
359 
360 				return (CRYPTO_DATA_LEN_RANGE);
361 			}
362 			break;
363 		}
364 		}
365 		return (CRYPTO_SUCCESS);
366 	}
367 
368 	/*
369 	 * We need to just return the length needed to store the output.
370 	 * We should not destroy the context for the following case.
371 	 */
372 
373 	if (input->cd_length > output->cd_length) {
374 		output->cd_length = input->cd_length;
375 		return (CRYPTO_BUFFER_TOO_SMALL);
376 	}
377 
378 	saveoffset = output->cd_offset;
379 
380 	switch (input->cd_format) {
381 	case CRYPTO_DATA_RAW: {
382 		char *start, *end;
383 		start = input->cd_raw.iov_base + input->cd_offset;
384 
385 		end =  input->cd_raw.iov_base + input->cd_raw.iov_len;
386 
387 		if (start + input->cd_length > end)
388 			return (CRYPTO_DATA_LEN_RANGE);
389 
390 		ret = crypto_arcfour_crypt(key, (uchar_t *)start, output,
391 		    input->cd_length);
392 
393 		if (ret != CRYPTO_SUCCESS)
394 			return (ret);
395 		break;
396 	}
397 	case CRYPTO_DATA_MBLK: {
398 		uchar_t *start, *end;
399 		size_t len, left;
400 		mblk_t *mp = input->cd_mp, *mp1, *mp2;
401 
402 		ASSERT(mp != NULL);
403 
404 		mp1 = advance_position(mp, input->cd_offset, &start);
405 
406 		if (mp1 == NULL)
407 			return (CRYPTO_DATA_LEN_RANGE);
408 
409 		mp2 = advance_position(mp, input->cd_offset + input->cd_length,
410 		    &end);
411 
412 		if (mp2 == NULL)
413 			return (CRYPTO_DATA_LEN_RANGE);
414 
415 		left = input->cd_length;
416 		while (mp1 != NULL) {
417 			if (_PTRDIFF(mp1->b_wptr, start) > left) {
418 				len = left;
419 				ret = crypto_arcfour_crypt(key, start, output,
420 				    len);
421 				if (ret != CRYPTO_SUCCESS)
422 					return (ret);
423 				mp1 = NULL;
424 			} else {
425 				len = _PTRDIFF(mp1->b_wptr, start);
426 				ret = crypto_arcfour_crypt(key, start, output,
427 				    len);
428 				if (ret != CRYPTO_SUCCESS)
429 					return (ret);
430 				mp1 = mp1->b_cont;
431 				start = mp1->b_rptr;
432 				left -= len;
433 				output->cd_offset += len;
434 			}
435 		}
436 		break;
437 	}
438 	case CRYPTO_DATA_UIO: {
439 		uio_t *uiop = input->cd_uio;
440 		off_t offset = input->cd_offset;
441 		size_t length = input->cd_length;
442 		uint_t vec_idx;
443 		size_t cur_len;
444 
445 		/*
446 		 * Jump to the first iovec containing data to be
447 		 * processed.
448 		 */
449 		for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
450 		    offset >= uiop->uio_iov[vec_idx].iov_len;
451 		    offset -= uiop->uio_iov[vec_idx++].iov_len)
452 			;
453 		if (vec_idx == uiop->uio_iovcnt) {
454 			return (CRYPTO_DATA_LEN_RANGE);
455 		}
456 
457 		/*
458 		 * Now process the iovecs.
459 		 */
460 		while (vec_idx < uiop->uio_iovcnt && length > 0) {
461 			uchar_t *start;
462 			iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
463 			cur_len = MIN(iovp->iov_len - offset, length);
464 
465 			start = (uchar_t *)(iovp->iov_base + offset);
466 			ret = crypto_arcfour_crypt(key, start + offset,
467 			    output, cur_len);
468 			if (ret != CRYPTO_SUCCESS)
469 				return (ret);
470 
471 			length -= cur_len;
472 			vec_idx++;
473 			offset = 0;
474 			output->cd_offset += cur_len;
475 		}
476 
477 		if (vec_idx == uiop->uio_iovcnt && length > 0) {
478 
479 			return (CRYPTO_DATA_LEN_RANGE);
480 		}
481 	}
482 	}
483 
484 	output->cd_offset = saveoffset;
485 	output->cd_length = input->cd_length;
486 
487 /* EXPORT DELETE END */
488 
489 	return (ret);
490 }
491 
492 /* ARGSUSED */
493 static int rc4_crypt_final(crypto_ctx_t *ctx, crypto_data_t *data,
494     crypto_req_handle_t req)
495 {
496 	/* No final part for streams ciphers. Just free the context */
497 	if (data != NULL)
498 		data->cd_length = 0;
499 
500 	return (rc4_free_context(ctx));
501 }
502 
503 /* ARGSUSED */
504 static int
505 rc4_crypt_atomic(crypto_provider_handle_t handle, crypto_session_id_t session,
506     crypto_mechanism_t *mechanism, crypto_key_t *key, crypto_data_t *input,
507     crypto_data_t *output, crypto_spi_ctx_template_t template,
508     crypto_req_handle_t req)
509 {
510 	crypto_ctx_t ctx;
511 	int ret;
512 
513 	bzero(&ctx, sizeof (crypto_ctx_t));
514 	ret = rc4_common_init(&ctx, mechanism, key, template, req);
515 
516 	if (ret != CRYPTO_SUCCESS)
517 		return (ret);
518 
519 	ret = rc4_crypt_update(&ctx, input, output, req);
520 
521 	(void) rc4_free_context(&ctx);
522 
523 	return (ret);
524 }
525 
526 /* ARGSUSED */
527 static int
528 rc4_free_context(crypto_ctx_t *ctx)
529 {
530 
531 /* EXPORT DELETE START */
532 
533 	ARCFour_key *keystream = ctx->cc_provider_private;
534 
535 	if (keystream != NULL) {
536 		bzero(keystream, sizeof (ARCFour_key));
537 		kmem_free(keystream, sizeof (ARCFour_key));
538 		ctx->cc_provider_private = NULL;
539 	}
540 
541 /* EXPORT DELETE END */
542 
543 	return (CRYPTO_SUCCESS);
544 }
545 
546 /* Encrypts a contiguous input 'in' into the 'out' crypto_data_t */
547 
548 static int
549 crypto_arcfour_crypt(ARCFour_key *key, uchar_t *in, crypto_data_t *out,
550     int length)
551 {
552 	switch (out->cd_format) {
553 		case CRYPTO_DATA_RAW: {
554 			uchar_t *start, *end;
555 			start = (uchar_t *)(out->cd_raw.iov_base +
556 			    out->cd_offset);
557 
558 			end = (uchar_t *)(out->cd_raw.iov_base +
559 			    out->cd_raw.iov_len);
560 
561 			if (start + out->cd_length > end)
562 				return (CRYPTO_DATA_LEN_RANGE);
563 
564 			arcfour_crypt(key, in, start, length);
565 
566 			return (CRYPTO_SUCCESS);
567 		}
568 		case CRYPTO_DATA_MBLK: {
569 			uchar_t *start, *end;
570 			size_t len, left;
571 			mblk_t *mp = out->cd_mp, *mp1, *mp2;
572 
573 			ASSERT(mp != NULL);
574 
575 			mp1 = advance_position(mp, out->cd_offset, &start);
576 
577 			if (mp1 == NULL)
578 				return (CRYPTO_DATA_LEN_RANGE);
579 
580 			mp2 = advance_position(mp, out->cd_offset +
581 			    out->cd_length, &end);
582 
583 			if (mp2 == NULL)
584 				return (CRYPTO_DATA_LEN_RANGE);
585 
586 			left = length;
587 			while (mp1 != NULL) {
588 				if (_PTRDIFF(mp1->b_wptr, start) > left) {
589 					len = left;
590 					arcfour_crypt(key, in, start, len);
591 					mp1 = NULL;
592 				} else {
593 					len = _PTRDIFF(mp1->b_wptr, start);
594 					arcfour_crypt(key, in, start, len);
595 					mp1 = mp1->b_cont;
596 					start = mp1->b_rptr;
597 					left -= len;
598 				}
599 			}
600 			break;
601 		}
602 		case CRYPTO_DATA_UIO: {
603 			uio_t *uiop = out->cd_uio;
604 			off_t offset = out->cd_offset;
605 			size_t len = length;
606 			uint_t vec_idx;
607 			size_t cur_len;
608 
609 			/*
610 			 * Jump to the first iovec containing data to be
611 			 * processed.
612 			 */
613 			for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
614 			    offset >= uiop->uio_iov[vec_idx].iov_len;
615 			    offset -= uiop->uio_iov[vec_idx++].iov_len)
616 				;
617 			if (vec_idx == uiop->uio_iovcnt) {
618 				return (CRYPTO_DATA_LEN_RANGE);
619 			}
620 
621 			/*
622 			 * Now process the iovecs.
623 			 */
624 			while (vec_idx < uiop->uio_iovcnt && len > 0) {
625 				uchar_t *start;
626 				iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
627 				cur_len = MIN(iovp->iov_len - offset, len);
628 
629 				start = (uchar_t *)(iovp->iov_base + offset);
630 				arcfour_crypt(key, start + offset,
631 				    start + offset, cur_len);
632 
633 				len -= cur_len;
634 				vec_idx++;
635 				offset = 0;
636 			}
637 
638 			if (vec_idx == uiop->uio_iovcnt && len > 0) {
639 				return (CRYPTO_DATA_LEN_RANGE);
640 			}
641 			break;
642 		}
643 		default:
644 			return (CRYPTO_DATA_INVALID);
645 	}
646 	return (CRYPTO_SUCCESS);
647 }
648 
649 /*
650  * Advances 'offset' bytes from the beginning of the first block in 'mp',
651  * possibly jumping across b_cont boundary
652  * '*cpp' is set to the position of the byte we want, and the block where
653  * 'cpp' is returned.
654  */
655 static mblk_t *
656 advance_position(mblk_t *mp, off_t offset, uchar_t **cpp)
657 {
658 	mblk_t *mp1 = mp;
659 	size_t l;
660 	off_t o = offset;
661 
662 	while (mp1 != NULL) {
663 		l = MBLKL(mp1);
664 
665 		if (l <= o) {
666 			o -= l;
667 			mp1 = mp1->b_cont;
668 		} else {
669 			*cpp = (uchar_t *)(mp1->b_rptr + o);
670 			break;
671 		}
672 	}
673 	return (mp1);
674 }
675