xref: /illumos-gate/usr/src/uts/common/crypto/io/arcfour.c (revision 7c478bd9)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * RC4 provider for the Kernel Cryptographic Framework (KCF)
31  */
32 
33 #include <sys/types.h>
34 #include <sys/systm.h>
35 #include <sys/modctl.h>
36 #include <sys/cmn_err.h>
37 #include <sys/ddi.h>
38 #include <sys/crypto/common.h>
39 #include <sys/crypto/spi.h>
40 #include <sys/sysmacros.h>
41 #include <sys/strsun.h>
42 #include <arcfour.h>
43 
44 extern struct mod_ops mod_cryptoops;
45 
46 /*
47  * Module linkage information for the kernel.
48  */
49 static struct modlcrypto modlcrypto = {
50 	&mod_cryptoops,
51 	"RC4 Kernel SW Provider %I%"
52 };
53 
54 static struct modlinkage modlinkage = {
55 	MODREV_1,
56 	(void *)&modlcrypto,
57 	NULL
58 };
59 
60 /*
61  * CSPI information (entry points, provider info, etc.)
62  */
63 
64 #define	RC4_MECH_INFO_TYPE	0
65 /*
66  * Mechanism info structure passed to KCF during registration.
67  */
68 static crypto_mech_info_t rc4_mech_info_tab[] = {
69 	{SUN_CKM_RC4, RC4_MECH_INFO_TYPE,
70 	    CRYPTO_FG_ENCRYPT | CRYPTO_FG_ENCRYPT_ATOMIC |
71 	    CRYPTO_FG_DECRYPT | CRYPTO_FG_DECRYPT_ATOMIC,
72 	    ARCFOUR_MIN_KEY_BITS, ARCFOUR_MAX_KEY_BITS,
73 	    CRYPTO_KEYSIZE_UNIT_IN_BITS}
74 };
75 
76 static void rc4_provider_status(crypto_provider_handle_t, uint_t *);
77 
78 static crypto_control_ops_t rc4_control_ops = {
79 	rc4_provider_status
80 };
81 
82 static int rc4_common_init(crypto_ctx_t *, crypto_mechanism_t *,
83     crypto_key_t *, crypto_spi_ctx_template_t, crypto_req_handle_t);
84 
85 static int rc4_crypt_update(crypto_ctx_t *, crypto_data_t *, crypto_data_t *,
86     crypto_req_handle_t);
87 
88 static int rc4_crypt_final(crypto_ctx_t *, crypto_data_t *,
89     crypto_req_handle_t);
90 
91 static int rc4_crypt(crypto_ctx_t *, crypto_data_t *, crypto_data_t *,
92     crypto_req_handle_t);
93 
94 static int rc4_crypt_atomic(crypto_provider_handle_t, crypto_session_id_t,
95     crypto_mechanism_t *, crypto_key_t *, crypto_data_t *,
96     crypto_data_t *, crypto_spi_ctx_template_t, crypto_req_handle_t);
97 
98 
99 static crypto_cipher_ops_t rc4_cipher_ops = {
100 	rc4_common_init,
101 	rc4_crypt,
102 	rc4_crypt_update,
103 	rc4_crypt_final,
104 	rc4_crypt_atomic,
105 	rc4_common_init,
106 	rc4_crypt,
107 	rc4_crypt_update,
108 	rc4_crypt_final,
109 	rc4_crypt_atomic
110 };
111 
112 static int rc4_free_context(crypto_ctx_t *);
113 
114 static crypto_ctx_ops_t rc4_ctx_ops = {
115 	NULL,
116 	rc4_free_context
117 };
118 
119 static crypto_ops_t rc4_crypto_ops = {
120 	&rc4_control_ops,
121 	NULL,
122 	&rc4_cipher_ops,
123 	NULL,
124 	NULL,
125 	NULL,
126 	NULL,
127 	NULL,
128 	NULL,
129 	NULL,
130 	NULL,
131 	NULL,
132 	NULL,
133 	&rc4_ctx_ops
134 };
135 
136 static crypto_provider_info_t rc4_prov_info = {
137 	CRYPTO_SPI_VERSION_1,
138 	"RC4 Software Provider",
139 	CRYPTO_SW_PROVIDER,
140 	{&modlinkage},
141 	NULL,
142 	&rc4_crypto_ops,
143 	sizeof (rc4_mech_info_tab)/sizeof (crypto_mech_info_t),
144 	rc4_mech_info_tab
145 };
146 
147 static crypto_kcf_provider_handle_t rc4_prov_handle = NULL;
148 
149 static mblk_t *advance_position(mblk_t *, off_t, uchar_t **);
150 static int crypto_arcfour_crypt(ARCFour_key *, uchar_t *, crypto_data_t *,
151     int);
152 
153 int
154 _init(void)
155 {
156 	int ret;
157 
158 	/*
159 	 * Register with KCF. If the registration fails, log an error
160 	 * and uninstall the module.
161 	 */
162 	if ((ret = crypto_register_provider(&rc4_prov_info,
163 	    &rc4_prov_handle)) != CRYPTO_SUCCESS) {
164 		cmn_err(CE_WARN, "_init: crypto_register_provider(%s)"
165 		    "failed (0x%x)", "arcfour", ret);
166 		return (EACCES);
167 	}
168 
169 	if ((ret = mod_install(&modlinkage)) != 0) {
170 		int rv;
171 
172 		ASSERT(rc4_prov_handle != NULL);
173 		/* We should not return if the unregister returns busy. */
174 		while ((rv = crypto_unregister_provider(rc4_prov_handle))
175 		    == CRYPTO_BUSY) {
176 			cmn_err(CE_WARN, "_init: crypto_unregister_provider(%s)"
177 			    " failed (0x%x). Retrying.", "arcfour", rv);
178 			/* wait 10 seconds and try again. */
179 			delay(10 * drv_usectohz(1000000));
180 		}
181 	}
182 
183 	return (0);
184 }
185 
186 int
187 _fini(void)
188 {
189 	int ret;
190 
191 	/*
192 	 * Unregister from KCF if previous registration succeeded.
193 	 */
194 	if (rc4_prov_handle != NULL) {
195 		if ((ret = crypto_unregister_provider(rc4_prov_handle)) !=
196 		    CRYPTO_SUCCESS) {
197 			cmn_err(CE_WARN, "_fini: crypto_unregister_provider(%s)"
198 			    " failed (0x%x)", "arcfour", ret);
199 			return (EBUSY);
200 		}
201 		rc4_prov_handle = NULL;
202 	}
203 
204 	return (mod_remove(&modlinkage));
205 }
206 
207 int
208 _info(struct modinfo *modinfop)
209 {
210 	return (mod_info(&modlinkage, modinfop));
211 }
212 
213 
214 /*
215  * KCF software provider control entry points.
216  */
217 /* ARGSUSED */
218 static void
219 rc4_provider_status(crypto_provider_handle_t provider, uint_t *status)
220 {
221 	*status = CRYPTO_PROVIDER_READY;
222 }
223 
224 /* ARGSUSED */
225 static int
226 rc4_common_init(crypto_ctx_t *ctx, crypto_mechanism_t *mechanism,
227     crypto_key_t *key, crypto_spi_ctx_template_t template,
228     crypto_req_handle_t req)
229 {
230 
231 /* EXPORT DELETE START */
232 
233 	ARCFour_key *keystream;
234 
235 	if ((mechanism)->cm_type != RC4_MECH_INFO_TYPE)
236 		return (CRYPTO_MECHANISM_INVALID);
237 
238 	if (key->ck_format != CRYPTO_KEY_RAW)
239 		return (CRYPTO_KEY_TYPE_INCONSISTENT);
240 
241 	if (key->ck_length < ARCFOUR_MIN_KEY_BITS ||
242 	    key->ck_length > ARCFOUR_MAX_KEY_BITS) {
243 		return (CRYPTO_KEY_SIZE_RANGE);
244 	}
245 
246 	/*
247 	 * Allocate an RC4 key stream.
248 	 */
249 	if ((keystream = kmem_alloc(sizeof (ARCFour_key),
250 	    crypto_kmflag(req))) == NULL)
251 		return (CRYPTO_HOST_MEMORY);
252 
253 	arcfour_key_init(keystream, key->ck_data, key->ck_length >> 3);
254 
255 	ctx->cc_provider_private = keystream;
256 
257 /* EXPORT DELETE END */
258 
259 	return (CRYPTO_SUCCESS);
260 }
261 
262 static int
263 rc4_crypt(crypto_ctx_t *ctx, crypto_data_t *input, crypto_data_t *output,
264     crypto_req_handle_t req)
265 {
266 	int ret;
267 
268 	ret = rc4_crypt_update(ctx, input, output, req);
269 
270 	if (ret != CRYPTO_BUFFER_TOO_SMALL)
271 		(void) rc4_free_context(ctx);
272 
273 	return (ret);
274 }
275 
276 /* ARGSUSED */
277 static int
278 rc4_crypt_update(crypto_ctx_t *ctx, crypto_data_t *input, crypto_data_t *output,
279     crypto_req_handle_t req)
280 {
281 	int ret = CRYPTO_SUCCESS;
282 
283 /* EXPORT DELETE START */
284 
285 	ARCFour_key *key;
286 	off_t saveoffset;
287 
288 	ASSERT(ctx->cc_provider_private != NULL);
289 
290 	key = ctx->cc_provider_private;
291 
292 	/* Simple case: in-line encipherment */
293 
294 	if (output == NULL) {
295 		switch (input->cd_format) {
296 		case CRYPTO_DATA_RAW: {
297 			char *start, *end;
298 			start = input->cd_raw.iov_base + input->cd_offset;
299 
300 			end =  input->cd_raw.iov_base + input->cd_raw.iov_len;
301 
302 			if (start + input->cd_length > end)
303 				return (CRYPTO_DATA_INVALID);
304 
305 			arcfour_crypt(key, (uchar_t *)start, (uchar_t *)start,
306 			    input->cd_length);
307 			break;
308 		}
309 		case CRYPTO_DATA_MBLK: {
310 			uchar_t *start, *end;
311 			size_t len, left;
312 			mblk_t *mp = input->cd_mp, *mp1, *mp2;
313 
314 			ASSERT(mp != NULL);
315 
316 			mp1 = advance_position(mp, input->cd_offset, &start);
317 
318 			if (mp1 == NULL)
319 				return (CRYPTO_DATA_LEN_RANGE);
320 
321 			mp2 = advance_position(mp, input->cd_offset +
322 			    input->cd_length, &end);
323 
324 			if (mp2 == NULL)
325 				return (CRYPTO_DATA_LEN_RANGE);
326 
327 			left = input->cd_length;
328 			while (mp1 != NULL) {
329 				if (mp1->b_wptr - start > left) {
330 					len = left;
331 					arcfour_crypt(key, start, start, len);
332 					mp1 = NULL;
333 				} else {
334 					len = mp1->b_wptr - start;
335 					arcfour_crypt(key, start, start, len);
336 					mp1 = mp1->b_cont;
337 					start = mp1->b_rptr;
338 					left -= len;
339 				}
340 			}
341 			break;
342 		}
343 		case CRYPTO_DATA_UIO: {
344 			uio_t *uiop = input->cd_uio;
345 			off_t offset = input->cd_offset;
346 			size_t length = input->cd_length;
347 			uint_t vec_idx;
348 			size_t cur_len;
349 
350 			/*
351 			 * Jump to the first iovec containing data to be
352 			 * processed.
353 			 */
354 			for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
355 			    offset >= uiop->uio_iov[vec_idx].iov_len;
356 			    offset -= uiop->uio_iov[vec_idx++].iov_len);
357 			if (vec_idx == uiop->uio_iovcnt) {
358 				return (CRYPTO_DATA_LEN_RANGE);
359 			}
360 
361 			/*
362 			 * Now process the iovecs.
363 			 */
364 			while (vec_idx < uiop->uio_iovcnt && length > 0) {
365 				uchar_t *start;
366 				iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
367 
368 				cur_len = MIN(iovp->iov_len - offset, length);
369 
370 				start = (uchar_t *)(iovp->iov_base + offset);
371 				arcfour_crypt(key, start + offset,
372 				    start + offset, cur_len);
373 
374 				length -= cur_len;
375 				vec_idx++;
376 				offset = 0;
377 			}
378 
379 			if (vec_idx == uiop->uio_iovcnt && length > 0) {
380 
381 				return (CRYPTO_DATA_LEN_RANGE);
382 			}
383 			break;
384 		}
385 		}
386 		return (CRYPTO_SUCCESS);
387 	}
388 
389 	/*
390 	 * We need to just return the length needed to store the output.
391 	 * We should not destroy the context for the following case.
392 	 */
393 
394 	if (input->cd_length > output->cd_length) {
395 		output->cd_length = input->cd_length;
396 		return (CRYPTO_BUFFER_TOO_SMALL);
397 	}
398 
399 	saveoffset = output->cd_offset;
400 
401 	switch (input->cd_format) {
402 	case CRYPTO_DATA_RAW: {
403 		char *start, *end;
404 		start = input->cd_raw.iov_base + input->cd_offset;
405 
406 		end =  input->cd_raw.iov_base + input->cd_raw.iov_len;
407 
408 		if (start + input->cd_length > end)
409 			return (CRYPTO_DATA_LEN_RANGE);
410 
411 		ret = crypto_arcfour_crypt(key, (uchar_t *)start, output,
412 		    input->cd_length);
413 
414 		if (ret != CRYPTO_SUCCESS)
415 			return (ret);
416 		break;
417 	}
418 	case CRYPTO_DATA_MBLK: {
419 		uchar_t *start, *end;
420 		size_t len, left;
421 		mblk_t *mp = input->cd_mp, *mp1, *mp2;
422 
423 		ASSERT(mp != NULL);
424 
425 		mp1 = advance_position(mp, input->cd_offset, &start);
426 
427 		if (mp1 == NULL)
428 			return (CRYPTO_DATA_LEN_RANGE);
429 
430 		mp2 = advance_position(mp, input->cd_offset + input->cd_length,
431 		    &end);
432 
433 		if (mp2 == NULL)
434 			return (CRYPTO_DATA_LEN_RANGE);
435 
436 		left = input->cd_length;
437 		while (mp1 != NULL) {
438 			if (mp1->b_wptr - start > left) {
439 				len = left;
440 				ret = crypto_arcfour_crypt(key, start, output,
441 				    len);
442 				if (ret != CRYPTO_SUCCESS)
443 					return (ret);
444 				mp1 = NULL;
445 			} else {
446 				len = mp1->b_wptr - start;
447 				ret = crypto_arcfour_crypt(key, start, output,
448 				    len);
449 				if (ret != CRYPTO_SUCCESS)
450 					return (ret);
451 				mp1 = mp1->b_cont;
452 				start = mp1->b_rptr;
453 				left -= len;
454 				output->cd_offset += len;
455 			}
456 		}
457 		break;
458 	}
459 	case CRYPTO_DATA_UIO: {
460 		uio_t *uiop = input->cd_uio;
461 		off_t offset = input->cd_offset;
462 		size_t length = input->cd_length;
463 		uint_t vec_idx;
464 		size_t cur_len;
465 
466 		/*
467 		 * Jump to the first iovec containing data to be
468 		 * processed.
469 		 */
470 		for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
471 		    offset >= uiop->uio_iov[vec_idx].iov_len;
472 		    offset -= uiop->uio_iov[vec_idx++].iov_len);
473 		if (vec_idx == uiop->uio_iovcnt) {
474 			return (CRYPTO_DATA_LEN_RANGE);
475 		}
476 
477 		/*
478 		 * Now process the iovecs.
479 		 */
480 		while (vec_idx < uiop->uio_iovcnt && length > 0) {
481 			uchar_t *start;
482 			iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
483 			cur_len = MIN(iovp->iov_len - offset, length);
484 
485 			start = (uchar_t *)(iovp->iov_base + offset);
486 			ret = crypto_arcfour_crypt(key, start + offset,
487 			    output, cur_len);
488 			if (ret != CRYPTO_SUCCESS)
489 				return (ret);
490 
491 			length -= cur_len;
492 			vec_idx++;
493 			offset = 0;
494 			output->cd_offset += cur_len;
495 		}
496 
497 		if (vec_idx == uiop->uio_iovcnt && length > 0) {
498 
499 			return (CRYPTO_DATA_LEN_RANGE);
500 		}
501 	}
502 	}
503 
504 	output->cd_offset = saveoffset;
505 	output->cd_length = input->cd_length;
506 
507 /* EXPORT DELETE END */
508 
509 	return (ret);
510 }
511 
512 /* ARGSUSED */
513 static int rc4_crypt_final(crypto_ctx_t *ctx, crypto_data_t *data,
514     crypto_req_handle_t req)
515 {
516 	/* No final part for streams ciphers. Just free the context */
517 	if (data != NULL)
518 		data->cd_length = 0;
519 
520 	return (rc4_free_context(ctx));
521 }
522 
523 /* ARGSUSED */
524 static int
525 rc4_crypt_atomic(crypto_provider_handle_t handle, crypto_session_id_t session,
526     crypto_mechanism_t *mechanism, crypto_key_t *key, crypto_data_t *input,
527     crypto_data_t *output, crypto_spi_ctx_template_t template,
528     crypto_req_handle_t req)
529 {
530 
531 	crypto_ctx_t ctx;
532 	int ret;
533 
534 	ret = rc4_common_init(&ctx, mechanism, key, template, req);
535 
536 	if (ret != CRYPTO_SUCCESS)
537 		return (ret);
538 
539 	ret = rc4_crypt_update(&ctx, input, output, req);
540 
541 	(void) rc4_free_context(&ctx);
542 
543 	return (ret);
544 }
545 
546 /* ARGSUSED */
547 static int
548 rc4_free_context(crypto_ctx_t *ctx)
549 {
550 
551 /* EXPORT DELETE START */
552 
553 	ARCFour_key *keystream = ctx->cc_provider_private;
554 
555 	if (keystream != NULL) {
556 		bzero(keystream, sizeof (ARCFour_key));
557 		kmem_free(keystream, sizeof (ARCFour_key));
558 		ctx->cc_provider_private = NULL;
559 	}
560 
561 /* EXPORT DELETE END */
562 
563 	return (CRYPTO_SUCCESS);
564 }
565 
566 /* Encrypts a contiguous input 'in' into the 'out' crypto_data_t */
567 
568 static int
569 crypto_arcfour_crypt(ARCFour_key *key, uchar_t *in, crypto_data_t *out,
570     int length)
571 {
572 	switch (out->cd_format) {
573 		case CRYPTO_DATA_RAW: {
574 			uchar_t *start, *end;
575 			start = (uchar_t *)(out->cd_raw.iov_base +
576 			    out->cd_offset);
577 
578 			end = (uchar_t *)(out->cd_raw.iov_base +
579 			    out->cd_raw.iov_len);
580 
581 			if (start + out->cd_length > end)
582 				return (CRYPTO_DATA_LEN_RANGE);
583 
584 			arcfour_crypt(key, in, start, length);
585 
586 			return (CRYPTO_SUCCESS);
587 		}
588 		case CRYPTO_DATA_MBLK: {
589 			uchar_t *start, *end;
590 			size_t len, left;
591 			mblk_t *mp = out->cd_mp, *mp1, *mp2;
592 
593 			ASSERT(mp != NULL);
594 
595 			mp1 = advance_position(mp, out->cd_offset, &start);
596 
597 			if (mp1 == NULL)
598 				return (CRYPTO_DATA_LEN_RANGE);
599 
600 			mp2 = advance_position(mp, out->cd_offset +
601 			    out->cd_length, &end);
602 
603 			if (mp2 == NULL)
604 				return (CRYPTO_DATA_LEN_RANGE);
605 
606 			left = length;
607 			while (mp1 != NULL) {
608 				if (mp1->b_wptr - start > left) {
609 					len = left;
610 					arcfour_crypt(key, in, start, len);
611 					mp1 = NULL;
612 				} else {
613 					len = mp1->b_wptr - start;
614 					arcfour_crypt(key, in, start, len);
615 					mp1 = mp1->b_cont;
616 					start = mp1->b_rptr;
617 					left -= len;
618 				}
619 			}
620 			break;
621 		}
622 		case CRYPTO_DATA_UIO: {
623 			uio_t *uiop = out->cd_uio;
624 			off_t offset = out->cd_offset;
625 			size_t len = length;
626 			uint_t vec_idx;
627 			size_t cur_len;
628 
629 			/*
630 			 * Jump to the first iovec containing data to be
631 			 * processed.
632 			 */
633 			for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
634 			    offset >= uiop->uio_iov[vec_idx].iov_len;
635 			    offset -= uiop->uio_iov[vec_idx++].iov_len);
636 			if (vec_idx == uiop->uio_iovcnt) {
637 				return (CRYPTO_DATA_LEN_RANGE);
638 			}
639 
640 			/*
641 			 * Now process the iovecs.
642 			 */
643 			while (vec_idx < uiop->uio_iovcnt && len > 0) {
644 				uchar_t *start;
645 				iovec_t *iovp = &(uiop->uio_iov[vec_idx]);
646 				cur_len = MIN(iovp->iov_len - offset, len);
647 
648 				start = (uchar_t *)(iovp->iov_base + offset);
649 				arcfour_crypt(key, start + offset,
650 				    start + offset, cur_len);
651 
652 				len -= cur_len;
653 				vec_idx++;
654 				offset = 0;
655 			}
656 
657 			if (vec_idx == uiop->uio_iovcnt && len > 0) {
658 				return (CRYPTO_DATA_LEN_RANGE);
659 			}
660 			break;
661 		}
662 		default:
663 			return (CRYPTO_DATA_INVALID);
664 	}
665 	return (CRYPTO_SUCCESS);
666 }
667 
668 /*
669  * Advances 'offset' bytes from the beginning of the first block in 'mp',
670  * possibly jumping across b_cont boundary
671  * '*cpp' is set to the position of the byte we want, and the block where
672  * 'cpp' is returned.
673  */
674 static mblk_t *
675 advance_position(mblk_t *mp, off_t offset, uchar_t **cpp)
676 {
677 	mblk_t *mp1 = mp;
678 	size_t l;
679 	off_t o = offset;
680 
681 	while (mp1 != NULL) {
682 		l = MBLKL(mp1);
683 
684 		if (l <= o) {
685 			o -= l;
686 			mp1 = mp1->b_cont;
687 		} else {
688 			*cpp = (uchar_t *)(mp1->b_rptr + o);
689 			break;
690 		}
691 	}
692 	return (mp1);
693 }
694