xref: /titanic_41/usr/src/uts/common/crypto/io/arcfour.c (revision bd7c6f51f14365fc31d408903b38c02177384d3d)
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 	/*
156 	 * Register with KCF. If the registration fails, log an error
157 	 * and uninstall the module.
158 	 */
159 	if ((ret = crypto_register_provider(&rc4_prov_info,
160 	    &rc4_prov_handle)) != CRYPTO_SUCCESS) {
161 		cmn_err(CE_WARN, "_init: crypto_register_provider(%s)"
162 		    "failed (0x%x)", "arcfour", ret);
163 		return (EACCES);
164 	}
165 
166 	if ((ret = mod_install(&modlinkage)) != 0) {
167 		int rv;
168 
169 		ASSERT(rc4_prov_handle != NULL);
170 		/* We should not return if the unregister returns busy. */
171 		while ((rv = crypto_unregister_provider(rc4_prov_handle))
172 		    == CRYPTO_BUSY) {
173 			cmn_err(CE_WARN, "_init: crypto_unregister_provider(%s)"
174 			    " failed (0x%x). Retrying.", "arcfour", rv);
175 			/* wait 10 seconds and try again. */
176 			delay(10 * drv_usectohz(1000000));
177 		}
178 	}
179 
180 	return (0);
181 }
182 
183 int
184 _fini(void)
185 {
186 	int ret;
187 
188 	/*
189 	 * Unregister from KCF if previous registration succeeded.
190 	 */
191 	if (rc4_prov_handle != NULL) {
192 		if ((ret = crypto_unregister_provider(rc4_prov_handle)) !=
193 		    CRYPTO_SUCCESS) {
194 			cmn_err(CE_WARN, "_fini: crypto_unregister_provider(%s)"
195 			    " failed (0x%x)", "arcfour", ret);
196 			return (EBUSY);
197 		}
198 		rc4_prov_handle = NULL;
199 	}
200 
201 	return (mod_remove(&modlinkage));
202 }
203 
204 int
205 _info(struct modinfo *modinfop)
206 {
207 	return (mod_info(&modlinkage, modinfop));
208 }
209 
210 
211 /*
212  * KCF software provider control entry points.
213  */
214 /* ARGSUSED */
215 static void
216 rc4_provider_status(crypto_provider_handle_t provider, uint_t *status)
217 {
218 	*status = CRYPTO_PROVIDER_READY;
219 }
220 
221 /* ARGSUSED */
222 static int
223 rc4_common_init(crypto_ctx_t *ctx, crypto_mechanism_t *mechanism,
224     crypto_key_t *key, crypto_spi_ctx_template_t template,
225     crypto_req_handle_t req)
226 {
227 
228 /* EXPORT DELETE START */
229 
230 	ARCFour_key *keystream;
231 
232 	if ((mechanism)->cm_type != RC4_MECH_INFO_TYPE)
233 		return (CRYPTO_MECHANISM_INVALID);
234 
235 	if (key->ck_format != CRYPTO_KEY_RAW)
236 		return (CRYPTO_KEY_TYPE_INCONSISTENT);
237 
238 	if (key->ck_length < ARCFOUR_MIN_KEY_BITS ||
239 	    key->ck_length > ARCFOUR_MAX_KEY_BITS) {
240 		return (CRYPTO_KEY_SIZE_RANGE);
241 	}
242 
243 	/*
244 	 * Allocate an RC4 key stream.
245 	 */
246 	if ((keystream = kmem_alloc(sizeof (ARCFour_key),
247 	    crypto_kmflag(req))) == NULL)
248 		return (CRYPTO_HOST_MEMORY);
249 
250 	arcfour_key_init(keystream, key->ck_data,
251 	    CRYPTO_BITS2BYTES(key->ck_length));
252 
253 	ctx->cc_provider_private = keystream;
254 
255 /* EXPORT DELETE END */
256 
257 	return (CRYPTO_SUCCESS);
258 }
259 
260 static int
261 rc4_crypt(crypto_ctx_t *ctx, crypto_data_t *input, crypto_data_t *output,
262     crypto_req_handle_t req)
263 {
264 	int ret;
265 
266 	ret = rc4_crypt_update(ctx, input, output, req);
267 
268 	if (ret != CRYPTO_BUFFER_TOO_SMALL)
269 		(void) rc4_free_context(ctx);
270 
271 	return (ret);
272 }
273 
274 /* ARGSUSED */
275 static int
276 rc4_crypt_update(crypto_ctx_t *ctx, crypto_data_t *input, crypto_data_t *output,
277     crypto_req_handle_t req)
278 {
279 	int ret = CRYPTO_SUCCESS;
280 
281 /* EXPORT DELETE START */
282 
283 	ARCFour_key *key;
284 	off_t saveoffset;
285 
286 	ASSERT(ctx->cc_provider_private != NULL);
287 
288 	if ((ctx->cc_flags & CRYPTO_USE_OPSTATE) && ctx->cc_opstate != NULL)
289 		key = ctx->cc_opstate;
290 	else
291 		key = ctx->cc_provider_private;
292 
293 	/* Simple case: in-line encipherment */
294 
295 	if (output == NULL) {
296 		switch (input->cd_format) {
297 		case CRYPTO_DATA_RAW: {
298 			char *start, *end;
299 			start = input->cd_raw.iov_base + input->cd_offset;
300 
301 			end =  input->cd_raw.iov_base + input->cd_raw.iov_len;
302 
303 			if (start + input->cd_length > end)
304 				return (CRYPTO_DATA_INVALID);
305 
306 			arcfour_crypt(key, (uchar_t *)start, (uchar_t *)start,
307 			    input->cd_length);
308 			break;
309 		}
310 		case CRYPTO_DATA_MBLK: {
311 			uchar_t *start, *end;
312 			size_t len, left;
313 			mblk_t *mp = input->cd_mp, *mp1, *mp2;
314 
315 			ASSERT(mp != NULL);
316 
317 			mp1 = advance_position(mp, input->cd_offset, &start);
318 
319 			if (mp1 == NULL)
320 				return (CRYPTO_DATA_LEN_RANGE);
321 
322 			mp2 = advance_position(mp, input->cd_offset +
323 			    input->cd_length, &end);
324 
325 			if (mp2 == NULL)
326 				return (CRYPTO_DATA_LEN_RANGE);
327 
328 			left = input->cd_length;
329 			while (mp1 != NULL) {
330 				if (_PTRDIFF(mp1->b_wptr, start) > left) {
331 					len = left;
332 					arcfour_crypt(key, start, start, len);
333 					mp1 = NULL;
334 				} else {
335 					len = _PTRDIFF(mp1->b_wptr, start);
336 					arcfour_crypt(key, start, start, len);
337 					mp1 = mp1->b_cont;
338 					start = mp1->b_rptr;
339 					left -= len;
340 				}
341 			}
342 			break;
343 		}
344 		case CRYPTO_DATA_UIO: {
345 			uio_t *uiop = input->cd_uio;
346 			off_t offset = input->cd_offset;
347 			size_t length = input->cd_length;
348 			uint_t vec_idx;
349 			size_t cur_len;
350 
351 			/*
352 			 * Jump to the first iovec containing data to be
353 			 * processed.
354 			 */
355 			for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
356 			    offset >= uiop->uio_iov[vec_idx].iov_len;
357 			    offset -= uiop->uio_iov[vec_idx++].iov_len)
358 				;
359 			if (vec_idx == uiop->uio_iovcnt) {
360 				return (CRYPTO_DATA_LEN_RANGE);
361 			}
362 
363 			/*
364 			 * Now process the iovecs.
365 			 */
366 			while (vec_idx < uiop->uio_iovcnt && length > 0) {
367 				uchar_t *start;
368 				iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
369 
370 				cur_len = MIN(iovp->iov_len - offset, length);
371 
372 				start = (uchar_t *)(iovp->iov_base + offset);
373 				arcfour_crypt(key, start + offset,
374 				    start + offset, cur_len);
375 
376 				length -= cur_len;
377 				vec_idx++;
378 				offset = 0;
379 			}
380 
381 			if (vec_idx == uiop->uio_iovcnt && length > 0) {
382 
383 				return (CRYPTO_DATA_LEN_RANGE);
384 			}
385 			break;
386 		}
387 		}
388 		return (CRYPTO_SUCCESS);
389 	}
390 
391 	/*
392 	 * We need to just return the length needed to store the output.
393 	 * We should not destroy the context for the following case.
394 	 */
395 
396 	if (input->cd_length > output->cd_length) {
397 		output->cd_length = input->cd_length;
398 		return (CRYPTO_BUFFER_TOO_SMALL);
399 	}
400 
401 	saveoffset = output->cd_offset;
402 
403 	switch (input->cd_format) {
404 	case CRYPTO_DATA_RAW: {
405 		char *start, *end;
406 		start = input->cd_raw.iov_base + input->cd_offset;
407 
408 		end =  input->cd_raw.iov_base + input->cd_raw.iov_len;
409 
410 		if (start + input->cd_length > end)
411 			return (CRYPTO_DATA_LEN_RANGE);
412 
413 		ret = crypto_arcfour_crypt(key, (uchar_t *)start, output,
414 		    input->cd_length);
415 
416 		if (ret != CRYPTO_SUCCESS)
417 			return (ret);
418 		break;
419 	}
420 	case CRYPTO_DATA_MBLK: {
421 		uchar_t *start, *end;
422 		size_t len, left;
423 		mblk_t *mp = input->cd_mp, *mp1, *mp2;
424 
425 		ASSERT(mp != NULL);
426 
427 		mp1 = advance_position(mp, input->cd_offset, &start);
428 
429 		if (mp1 == NULL)
430 			return (CRYPTO_DATA_LEN_RANGE);
431 
432 		mp2 = advance_position(mp, input->cd_offset + input->cd_length,
433 		    &end);
434 
435 		if (mp2 == NULL)
436 			return (CRYPTO_DATA_LEN_RANGE);
437 
438 		left = input->cd_length;
439 		while (mp1 != NULL) {
440 			if (_PTRDIFF(mp1->b_wptr, start) > left) {
441 				len = left;
442 				ret = crypto_arcfour_crypt(key, start, output,
443 				    len);
444 				if (ret != CRYPTO_SUCCESS)
445 					return (ret);
446 				mp1 = NULL;
447 			} else {
448 				len = _PTRDIFF(mp1->b_wptr, start);
449 				ret = crypto_arcfour_crypt(key, start, output,
450 				    len);
451 				if (ret != CRYPTO_SUCCESS)
452 					return (ret);
453 				mp1 = mp1->b_cont;
454 				start = mp1->b_rptr;
455 				left -= len;
456 				output->cd_offset += len;
457 			}
458 		}
459 		break;
460 	}
461 	case CRYPTO_DATA_UIO: {
462 		uio_t *uiop = input->cd_uio;
463 		off_t offset = input->cd_offset;
464 		size_t length = input->cd_length;
465 		uint_t vec_idx;
466 		size_t cur_len;
467 
468 		/*
469 		 * Jump to the first iovec containing data to be
470 		 * processed.
471 		 */
472 		for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
473 		    offset >= uiop->uio_iov[vec_idx].iov_len;
474 		    offset -= uiop->uio_iov[vec_idx++].iov_len)
475 			;
476 		if (vec_idx == uiop->uio_iovcnt) {
477 			return (CRYPTO_DATA_LEN_RANGE);
478 		}
479 
480 		/*
481 		 * Now process the iovecs.
482 		 */
483 		while (vec_idx < uiop->uio_iovcnt && length > 0) {
484 			uchar_t *start;
485 			iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
486 			cur_len = MIN(iovp->iov_len - offset, length);
487 
488 			start = (uchar_t *)(iovp->iov_base + offset);
489 			ret = crypto_arcfour_crypt(key, start + offset,
490 			    output, cur_len);
491 			if (ret != CRYPTO_SUCCESS)
492 				return (ret);
493 
494 			length -= cur_len;
495 			vec_idx++;
496 			offset = 0;
497 			output->cd_offset += cur_len;
498 		}
499 
500 		if (vec_idx == uiop->uio_iovcnt && length > 0) {
501 
502 			return (CRYPTO_DATA_LEN_RANGE);
503 		}
504 	}
505 	}
506 
507 	output->cd_offset = saveoffset;
508 	output->cd_length = input->cd_length;
509 
510 /* EXPORT DELETE END */
511 
512 	return (ret);
513 }
514 
515 /* ARGSUSED */
516 static int rc4_crypt_final(crypto_ctx_t *ctx, crypto_data_t *data,
517     crypto_req_handle_t req)
518 {
519 	/* No final part for streams ciphers. Just free the context */
520 	if (data != NULL)
521 		data->cd_length = 0;
522 
523 	return (rc4_free_context(ctx));
524 }
525 
526 /* ARGSUSED */
527 static int
528 rc4_crypt_atomic(crypto_provider_handle_t handle, crypto_session_id_t session,
529     crypto_mechanism_t *mechanism, crypto_key_t *key, crypto_data_t *input,
530     crypto_data_t *output, crypto_spi_ctx_template_t template,
531     crypto_req_handle_t req)
532 {
533 	crypto_ctx_t ctx;
534 	int ret;
535 
536 	bzero(&ctx, sizeof (crypto_ctx_t));
537 	ret = rc4_common_init(&ctx, mechanism, key, template, req);
538 
539 	if (ret != CRYPTO_SUCCESS)
540 		return (ret);
541 
542 	ret = rc4_crypt_update(&ctx, input, output, req);
543 
544 	(void) rc4_free_context(&ctx);
545 
546 	return (ret);
547 }
548 
549 /* ARGSUSED */
550 static int
551 rc4_free_context(crypto_ctx_t *ctx)
552 {
553 
554 /* EXPORT DELETE START */
555 
556 	ARCFour_key *keystream = ctx->cc_provider_private;
557 
558 	if (keystream != NULL) {
559 		bzero(keystream, sizeof (ARCFour_key));
560 		kmem_free(keystream, sizeof (ARCFour_key));
561 		ctx->cc_provider_private = NULL;
562 	}
563 
564 /* EXPORT DELETE END */
565 
566 	return (CRYPTO_SUCCESS);
567 }
568 
569 /* Encrypts a contiguous input 'in' into the 'out' crypto_data_t */
570 
571 static int
572 crypto_arcfour_crypt(ARCFour_key *key, uchar_t *in, crypto_data_t *out,
573     int length)
574 {
575 	switch (out->cd_format) {
576 		case CRYPTO_DATA_RAW: {
577 			uchar_t *start, *end;
578 			start = (uchar_t *)(out->cd_raw.iov_base +
579 			    out->cd_offset);
580 
581 			end = (uchar_t *)(out->cd_raw.iov_base +
582 			    out->cd_raw.iov_len);
583 
584 			if (start + out->cd_length > end)
585 				return (CRYPTO_DATA_LEN_RANGE);
586 
587 			arcfour_crypt(key, in, start, length);
588 
589 			return (CRYPTO_SUCCESS);
590 		}
591 		case CRYPTO_DATA_MBLK: {
592 			uchar_t *start, *end;
593 			size_t len, left;
594 			mblk_t *mp = out->cd_mp, *mp1, *mp2;
595 
596 			ASSERT(mp != NULL);
597 
598 			mp1 = advance_position(mp, out->cd_offset, &start);
599 
600 			if (mp1 == NULL)
601 				return (CRYPTO_DATA_LEN_RANGE);
602 
603 			mp2 = advance_position(mp, out->cd_offset +
604 			    out->cd_length, &end);
605 
606 			if (mp2 == NULL)
607 				return (CRYPTO_DATA_LEN_RANGE);
608 
609 			left = length;
610 			while (mp1 != NULL) {
611 				if (_PTRDIFF(mp1->b_wptr, start) > left) {
612 					len = left;
613 					arcfour_crypt(key, in, start, len);
614 					mp1 = NULL;
615 				} else {
616 					len = _PTRDIFF(mp1->b_wptr, start);
617 					arcfour_crypt(key, in, start, len);
618 					mp1 = mp1->b_cont;
619 					start = mp1->b_rptr;
620 					left -= len;
621 				}
622 			}
623 			break;
624 		}
625 		case CRYPTO_DATA_UIO: {
626 			uio_t *uiop = out->cd_uio;
627 			off_t offset = out->cd_offset;
628 			size_t len = length;
629 			uint_t vec_idx;
630 			size_t cur_len;
631 
632 			/*
633 			 * Jump to the first iovec containing data to be
634 			 * processed.
635 			 */
636 			for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
637 			    offset >= uiop->uio_iov[vec_idx].iov_len;
638 			    offset -= uiop->uio_iov[vec_idx++].iov_len)
639 				;
640 			if (vec_idx == uiop->uio_iovcnt) {
641 				return (CRYPTO_DATA_LEN_RANGE);
642 			}
643 
644 			/*
645 			 * Now process the iovecs.
646 			 */
647 			while (vec_idx < uiop->uio_iovcnt && len > 0) {
648 				uchar_t *start;
649 				iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
650 				cur_len = MIN(iovp->iov_len - offset, len);
651 
652 				start = (uchar_t *)(iovp->iov_base + offset);
653 				arcfour_crypt(key, start + offset,
654 				    start + offset, cur_len);
655 
656 				len -= cur_len;
657 				vec_idx++;
658 				offset = 0;
659 			}
660 
661 			if (vec_idx == uiop->uio_iovcnt && len > 0) {
662 				return (CRYPTO_DATA_LEN_RANGE);
663 			}
664 			break;
665 		}
666 		default:
667 			return (CRYPTO_DATA_INVALID);
668 	}
669 	return (CRYPTO_SUCCESS);
670 }
671 
672 /*
673  * Advances 'offset' bytes from the beginning of the first block in 'mp',
674  * possibly jumping across b_cont boundary
675  * '*cpp' is set to the position of the byte we want, and the block where
676  * 'cpp' is returned.
677  */
678 static mblk_t *
679 advance_position(mblk_t *mp, off_t offset, uchar_t **cpp)
680 {
681 	mblk_t *mp1 = mp;
682 	size_t l;
683 	off_t o = offset;
684 
685 	while (mp1 != NULL) {
686 		l = MBLKL(mp1);
687 
688 		if (l <= o) {
689 			o -= l;
690 			mp1 = mp1->b_cont;
691 		} else {
692 			*cpp = (uchar_t *)(mp1->b_rptr + o);
693 			break;
694 		}
695 	}
696 	return (mp1);
697 }
698