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
41extern struct mod_ops mod_cryptoops;
42
43/*
44 * Module linkage information for the kernel.
45 */
46static struct modlcrypto modlcrypto = {
47	&mod_cryptoops,
48	"RC4 Kernel SW Provider"
49};
50
51static 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 */
65static 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
73static void rc4_provider_status(crypto_provider_handle_t, uint_t *);
74
75static crypto_control_ops_t rc4_control_ops = {
76	rc4_provider_status
77};
78
79static int rc4_common_init(crypto_ctx_t *, crypto_mechanism_t *,
80    crypto_key_t *, crypto_spi_ctx_template_t, crypto_req_handle_t);
81
82static int rc4_crypt_update(crypto_ctx_t *, crypto_data_t *, crypto_data_t *,
83    crypto_req_handle_t);
84
85static int rc4_crypt_final(crypto_ctx_t *, crypto_data_t *,
86    crypto_req_handle_t);
87
88static int rc4_crypt(crypto_ctx_t *, crypto_data_t *, crypto_data_t *,
89    crypto_req_handle_t);
90
91static 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
96static 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
109static int rc4_free_context(crypto_ctx_t *);
110
111static crypto_ctx_ops_t rc4_ctx_ops = {
112	NULL,
113	rc4_free_context
114};
115
116static 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
133static 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
144static crypto_kcf_provider_handle_t rc4_prov_handle = NULL;
145
146static mblk_t *advance_position(mblk_t *, off_t, uchar_t **);
147static int crypto_arcfour_crypt(ARCFour_key *, uchar_t *, crypto_data_t *,
148    int);
149
150int
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
167int
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
181int
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 */
192static void
193rc4_provider_status(crypto_provider_handle_t provider, uint_t *status)
194{
195	*status = CRYPTO_PROVIDER_READY;
196}
197
198/* ARGSUSED */
199static int
200rc4_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
237static int
238rc4_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 */
252static int
253rc4_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 */
493static 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 */
504static int
505rc4_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 */
527static int
528rc4_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
548static int
549crypto_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 */
655static mblk_t *
656advance_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