xref: /freebsd/sys/opencrypto/criov.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*      $OpenBSD: criov.c,v 1.9 2002/01/29 15:48:29 jason Exp $	*/
2 
3 /*-
4  * Copyright (c) 1999 Theo de Raadt
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *   notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *   notice, this list of conditions and the following disclaimer in the
14  *   documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *   derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/proc.h>
33 #include <sys/errno.h>
34 #include <sys/malloc.h>
35 #include <sys/kernel.h>
36 #include <sys/mbuf.h>
37 #include <sys/uio.h>
38 #include <sys/limits.h>
39 #include <sys/lock.h>
40 #include <sys/sdt.h>
41 
42 #include <machine/vmparam.h>
43 
44 #include <vm/vm.h>
45 #include <vm/vm_page.h>
46 #include <vm/pmap.h>
47 
48 #include <opencrypto/cryptodev.h>
49 
50 SDT_PROVIDER_DECLARE(opencrypto);
51 
52 /*
53  * These macros are only for avoiding code duplication, as we need to skip
54  * given number of bytes in the same way in several functions below.
55  */
56 #define	CUIO_SKIP()	do {						\
57 	KASSERT(off >= 0, ("%s: off %d < 0", __func__, off));		\
58 	KASSERT(len >= 0, ("%s: len %d < 0", __func__, len));		\
59 	while (off > 0) {						\
60 		KASSERT(iol >= 0, ("%s: empty in skip", __func__));	\
61 		if (off < iov->iov_len)					\
62 			break;						\
63 		off -= iov->iov_len;					\
64 		iol--;							\
65 		iov++;							\
66 	}								\
67 } while (0)
68 
69 #define CVM_PAGE_SKIP()	do {					\
70 	KASSERT(off >= 0, ("%s: off %d < 0", __func__, off));		\
71 	KASSERT(len >= 0, ("%s: len %d < 0", __func__, len));		\
72 	while (off > 0) {						\
73 		if (off < PAGE_SIZE)					\
74 			break;						\
75 		processed += PAGE_SIZE - off;				\
76 		off -= PAGE_SIZE - off;					\
77 		pages++;						\
78 	}								\
79 } while (0)
80 
81 static void
82 cuio_copydata(struct uio* uio, int off, int len, caddr_t cp)
83 {
84 	struct iovec *iov = uio->uio_iov;
85 	int iol __diagused = uio->uio_iovcnt;
86 	unsigned count;
87 
88 	CUIO_SKIP();
89 	while (len > 0) {
90 		KASSERT(iol >= 0, ("%s: empty", __func__));
91 		count = min(iov->iov_len - off, len);
92 		bcopy(((caddr_t)iov->iov_base) + off, cp, count);
93 		len -= count;
94 		cp += count;
95 		off = 0;
96 		iol--;
97 		iov++;
98 	}
99 }
100 
101 static void
102 cuio_copyback(struct uio* uio, int off, int len, c_caddr_t cp)
103 {
104 	struct iovec *iov = uio->uio_iov;
105 	int iol __diagused = uio->uio_iovcnt;
106 	unsigned count;
107 
108 	CUIO_SKIP();
109 	while (len > 0) {
110 		KASSERT(iol >= 0, ("%s: empty", __func__));
111 		count = min(iov->iov_len - off, len);
112 		bcopy(cp, ((caddr_t)iov->iov_base) + off, count);
113 		len -= count;
114 		cp += count;
115 		off = 0;
116 		iol--;
117 		iov++;
118 	}
119 }
120 
121 /*
122  * Return the index and offset of location in iovec list.
123  */
124 static int
125 cuio_getptr(struct uio *uio, int loc, int *off)
126 {
127 	int ind, len;
128 
129 	ind = 0;
130 	while (loc >= 0 && ind < uio->uio_iovcnt) {
131 		len = uio->uio_iov[ind].iov_len;
132 		if (len > loc) {
133 	    		*off = loc;
134 	    		return (ind);
135 		}
136 		loc -= len;
137 		ind++;
138 	}
139 
140 	if (ind > 0 && loc == 0) {
141 		ind--;
142 		*off = uio->uio_iov[ind].iov_len;
143 		return (ind);
144 	}
145 
146 	return (-1);
147 }
148 
149 #if CRYPTO_MAY_HAVE_VMPAGE
150 /*
151  * Apply function f to the data in a vm_page_t list starting "off" bytes from
152  * the beginning, continuing for "len" bytes.
153  */
154 static int
155 cvm_page_apply(vm_page_t *pages, int off, int len,
156     int (*f)(void *, const void *, u_int), void *arg)
157 {
158 	int processed __unused;
159 	unsigned count;
160 	int rval;
161 
162 	processed = 0;
163 	CVM_PAGE_SKIP();
164 	while (len > 0) {
165 		char *kaddr = (char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(*pages));
166 		count = min(PAGE_SIZE - off, len);
167 		rval = (*f)(arg, kaddr + off, count);
168 		if (rval)
169 			return (rval);
170 		len -= count;
171 		processed += count;
172 		off = 0;
173 		pages++;
174 	}
175 	return (0);
176 }
177 
178 static inline void *
179 cvm_page_contiguous_segment(vm_page_t *pages, size_t skip, int len)
180 {
181 	if ((skip + len - 1) / PAGE_SIZE > skip / PAGE_SIZE)
182 		return (NULL);
183 
184 	pages += (skip / PAGE_SIZE);
185 	skip -= rounddown(skip, PAGE_SIZE);
186 	return (((char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(*pages))) + skip);
187 }
188 
189 /*
190  * Copy len bytes of data from the vm_page_t array, skipping the first off
191  * bytes, into the pointer cp.  Return the number of bytes skipped and copied.
192  * Does not verify the length of the array.
193  */
194 static int
195 cvm_page_copyback(vm_page_t *pages, int off, int len, c_caddr_t cp)
196 {
197 	int processed = 0;
198 	unsigned count;
199 
200 	CVM_PAGE_SKIP();
201 	while (len > 0) {
202 		count = min(PAGE_SIZE - off, len);
203 		bcopy(cp, (char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(*pages)) + off,
204 		    count);
205 		len -= count;
206 		cp += count;
207 		processed += count;
208 		off = 0;
209 		pages++;
210 	}
211 	return (processed);
212 }
213 
214 /*
215  * Copy len bytes of data from the pointer cp into the vm_page_t array,
216  * skipping the first off bytes, Return the number of bytes skipped and copied.
217  * Does not verify the length of the array.
218  */
219 static int
220 cvm_page_copydata(vm_page_t *pages, int off, int len, caddr_t cp)
221 {
222 	int processed = 0;
223 	unsigned count;
224 
225 	CVM_PAGE_SKIP();
226 	while (len > 0) {
227 		count = min(PAGE_SIZE - off, len);
228 		bcopy(((char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(*pages)) + off), cp,
229 		    count);
230 		len -= count;
231 		cp += count;
232 		processed += count;
233 		off = 0;
234 		pages++;
235 	}
236 	return processed;
237 }
238 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
239 
240 /*
241  * Given a starting page in an m_epg, determine the length of the
242  * current physically contiguous segment.
243  */
244 static __inline size_t
245 m_epg_pages_extent(struct mbuf *m, int idx, u_int pglen)
246 {
247 	size_t len;
248 	u_int i;
249 
250 	len = pglen;
251 	for (i = idx + 1; i < m->m_epg_npgs; i++) {
252 		if (m->m_epg_pa[i - 1] + PAGE_SIZE != m->m_epg_pa[i])
253 			break;
254 		len += m_epg_pagelen(m, i, 0);
255 	}
256 	return (len);
257 }
258 
259 static void *
260 m_epg_segment(struct mbuf *m, size_t offset, size_t *len)
261 {
262 	u_int i, pglen, pgoff;
263 
264 	offset += mtod(m, vm_offset_t);
265 	if (offset < m->m_epg_hdrlen) {
266 		*len = m->m_epg_hdrlen - offset;
267 		return (m->m_epg_hdr + offset);
268 	}
269 	offset -= m->m_epg_hdrlen;
270 	pgoff = m->m_epg_1st_off;
271 	for (i = 0; i < m->m_epg_npgs; i++) {
272 		pglen = m_epg_pagelen(m, i, pgoff);
273 		if (offset < pglen) {
274 			*len = m_epg_pages_extent(m, i, pglen) - offset;
275 			return ((void *)PHYS_TO_DMAP(m->m_epg_pa[i] + pgoff +
276 			    offset));
277 		}
278 		offset -= pglen;
279 		pgoff = 0;
280 	}
281 	KASSERT(offset <= m->m_epg_trllen, ("%s: offset beyond trailer",
282 	    __func__));
283 	*len = m->m_epg_trllen - offset;
284 	return (m->m_epg_trail + offset);
285 }
286 
287 static __inline void *
288 m_epg_contiguous_subsegment(struct mbuf *m, size_t skip, size_t len)
289 {
290 	void *base;
291 	size_t seglen;
292 
293 	base = m_epg_segment(m, skip, &seglen);
294 	if (len > seglen)
295 		return (NULL);
296 	return (base);
297 }
298 
299 void
300 crypto_cursor_init(struct crypto_buffer_cursor *cc,
301     const struct crypto_buffer *cb)
302 {
303 	memset(cc, 0, sizeof(*cc));
304 	cc->cc_type = cb->cb_type;
305 	switch (cc->cc_type) {
306 	case CRYPTO_BUF_CONTIG:
307 		cc->cc_buf = cb->cb_buf;
308 		cc->cc_buf_len = cb->cb_buf_len;
309 		break;
310 	case CRYPTO_BUF_MBUF:
311 	case CRYPTO_BUF_SINGLE_MBUF:
312 		cc->cc_mbuf = cb->cb_mbuf;
313 		break;
314 	case CRYPTO_BUF_VMPAGE:
315 		cc->cc_vmpage = cb->cb_vm_page;
316 		cc->cc_buf_len = cb->cb_vm_page_len;
317 		cc->cc_offset = cb->cb_vm_page_offset;
318 		break;
319 	case CRYPTO_BUF_UIO:
320 		cc->cc_iov = cb->cb_uio->uio_iov;
321 		cc->cc_buf_len = cb->cb_uio->uio_resid;
322 		break;
323 	default:
324 #ifdef INVARIANTS
325 		panic("%s: invalid buffer type %d", __func__, cb->cb_type);
326 #endif
327 		break;
328 	}
329 }
330 
331 SDT_PROBE_DEFINE2(opencrypto, criov, cursor_advance, vmpage, "struct crypto_buffer_cursor*", "size_t");
332 
333 void
334 crypto_cursor_advance(struct crypto_buffer_cursor *cc, size_t amount)
335 {
336 	size_t remain;
337 
338 	switch (cc->cc_type) {
339 	case CRYPTO_BUF_CONTIG:
340 		MPASS(cc->cc_buf_len >= amount);
341 		cc->cc_buf += amount;
342 		cc->cc_buf_len -= amount;
343 		break;
344 	case CRYPTO_BUF_MBUF:
345 		for (;;) {
346 			remain = cc->cc_mbuf->m_len - cc->cc_offset;
347 			if (amount < remain) {
348 				cc->cc_offset += amount;
349 				break;
350 			}
351 			amount -= remain;
352 			cc->cc_mbuf = cc->cc_mbuf->m_next;
353 			cc->cc_offset = 0;
354 			if (amount == 0)
355 				break;
356 		}
357 		break;
358 	case CRYPTO_BUF_SINGLE_MBUF:
359 		MPASS(cc->cc_mbuf->m_len >= cc->cc_offset + amount);
360 		cc->cc_offset += amount;
361 		break;
362 	case CRYPTO_BUF_VMPAGE:
363 		for (;;) {
364 			SDT_PROBE2(opencrypto, criov, cursor_advance, vmpage,
365 			    cc, amount);
366 			remain = MIN(PAGE_SIZE - cc->cc_offset, cc->cc_buf_len);
367 			if (amount < remain) {
368 				cc->cc_buf_len -= amount;
369 				cc->cc_offset += amount;
370 				break;
371 			}
372 			cc->cc_buf_len -= remain;
373 			amount -= remain;
374 			cc->cc_vmpage++;
375 			cc->cc_offset = 0;
376 			if (amount == 0 || cc->cc_buf_len == 0)
377 				break;
378 		}
379 		break;
380 	case CRYPTO_BUF_UIO:
381 		for (;;) {
382 			remain = cc->cc_iov->iov_len - cc->cc_offset;
383 			if (amount < remain) {
384 				cc->cc_offset += amount;
385 				break;
386 			}
387 			cc->cc_buf_len -= remain;
388 			amount -= remain;
389 			cc->cc_iov++;
390 			cc->cc_offset = 0;
391 			if (amount == 0)
392 				break;
393 		}
394 		break;
395 	default:
396 #ifdef INVARIANTS
397 		panic("%s: invalid buffer type %d", __func__, cc->cc_type);
398 #endif
399 		break;
400 	}
401 }
402 
403 void *
404 crypto_cursor_segment(struct crypto_buffer_cursor *cc, size_t *len)
405 {
406 	switch (cc->cc_type) {
407 	case CRYPTO_BUF_CONTIG:
408 	case CRYPTO_BUF_UIO:
409 	case CRYPTO_BUF_VMPAGE:
410 		if (cc->cc_buf_len == 0) {
411 			*len = 0;
412 			return (NULL);
413 		}
414 		break;
415 	case CRYPTO_BUF_MBUF:
416 	case CRYPTO_BUF_SINGLE_MBUF:
417 		if (cc->cc_mbuf == NULL) {
418 			*len = 0;
419 			return (NULL);
420 		}
421 		break;
422 	default:
423 #ifdef INVARIANTS
424 		panic("%s: invalid buffer type %d", __func__, cc->cc_type);
425 #endif
426 		*len = 0;
427 		return (NULL);
428 	}
429 
430 	switch (cc->cc_type) {
431 	case CRYPTO_BUF_CONTIG:
432 		*len = cc->cc_buf_len;
433 		return (cc->cc_buf);
434 	case CRYPTO_BUF_MBUF:
435 	case CRYPTO_BUF_SINGLE_MBUF:
436 		if (cc->cc_mbuf->m_flags & M_EXTPG)
437 			return (m_epg_segment(cc->cc_mbuf, cc->cc_offset, len));
438 		*len = cc->cc_mbuf->m_len - cc->cc_offset;
439 		return (mtod(cc->cc_mbuf, char *) + cc->cc_offset);
440 	case CRYPTO_BUF_VMPAGE:
441 		*len = PAGE_SIZE - cc->cc_offset;
442 		return ((char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(
443 		    *cc->cc_vmpage)) + cc->cc_offset);
444 	case CRYPTO_BUF_UIO:
445 		*len = cc->cc_iov->iov_len - cc->cc_offset;
446 		return ((char *)cc->cc_iov->iov_base + cc->cc_offset);
447 	default:
448 		__assert_unreachable();
449 	}
450 }
451 
452 void
453 crypto_cursor_copyback(struct crypto_buffer_cursor *cc, int size,
454     const void *vsrc)
455 {
456 	size_t remain, todo;
457 	const char *src;
458 	char *dst;
459 
460 	src = vsrc;
461 	switch (cc->cc_type) {
462 	case CRYPTO_BUF_CONTIG:
463 		MPASS(cc->cc_buf_len >= size);
464 		memcpy(cc->cc_buf, src, size);
465 		cc->cc_buf += size;
466 		cc->cc_buf_len -= size;
467 		break;
468 	case CRYPTO_BUF_MBUF:
469 		for (;;) {
470 			/*
471 			 * This uses m_copyback() for individual
472 			 * mbufs so that cc_mbuf and cc_offset are
473 			 * updated.
474 			 */
475 			remain = cc->cc_mbuf->m_len - cc->cc_offset;
476 			todo = MIN(remain, size);
477 			m_copyback(cc->cc_mbuf, cc->cc_offset, todo, src);
478 			src += todo;
479 			if (todo < remain) {
480 				cc->cc_offset += todo;
481 				break;
482 			}
483 			size -= todo;
484 			cc->cc_mbuf = cc->cc_mbuf->m_next;
485 			cc->cc_offset = 0;
486 			if (size == 0)
487 				break;
488 		}
489 		break;
490 	case CRYPTO_BUF_SINGLE_MBUF:
491 		MPASS(cc->cc_mbuf->m_len >= cc->cc_offset + size);
492 		m_copyback(cc->cc_mbuf, cc->cc_offset, size, src);
493 		cc->cc_offset += size;
494 		break;
495 	case CRYPTO_BUF_VMPAGE:
496 		for (;;) {
497 			dst = (char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(
498 			    *cc->cc_vmpage)) + cc->cc_offset;
499 			remain = MIN(PAGE_SIZE - cc->cc_offset, cc->cc_buf_len);
500 			todo = MIN(remain, size);
501 			memcpy(dst, src, todo);
502 			src += todo;
503 			cc->cc_buf_len -= todo;
504 			if (todo < remain) {
505 				cc->cc_offset += todo;
506 				break;
507 			}
508 			size -= todo;
509 			cc->cc_vmpage++;
510 			cc->cc_offset = 0;
511 			if (size == 0)
512 				break;
513 		}
514 		break;
515 	case CRYPTO_BUF_UIO:
516 		for (;;) {
517 			dst = (char *)cc->cc_iov->iov_base + cc->cc_offset;
518 			remain = cc->cc_iov->iov_len - cc->cc_offset;
519 			todo = MIN(remain, size);
520 			memcpy(dst, src, todo);
521 			src += todo;
522 			cc->cc_buf_len -= todo;
523 			if (todo < remain) {
524 				cc->cc_offset += todo;
525 				break;
526 			}
527 			size -= todo;
528 			cc->cc_iov++;
529 			cc->cc_offset = 0;
530 			if (size == 0)
531 				break;
532 		}
533 		break;
534 	default:
535 #ifdef INVARIANTS
536 		panic("%s: invalid buffer type %d", __func__, cc->cc_type);
537 #endif
538 		break;
539 	}
540 }
541 
542 void
543 crypto_cursor_copydata(struct crypto_buffer_cursor *cc, int size, void *vdst)
544 {
545 	size_t remain, todo;
546 	const char *src;
547 	char *dst;
548 
549 	dst = vdst;
550 	switch (cc->cc_type) {
551 	case CRYPTO_BUF_CONTIG:
552 		MPASS(cc->cc_buf_len >= size);
553 		memcpy(dst, cc->cc_buf, size);
554 		cc->cc_buf += size;
555 		cc->cc_buf_len -= size;
556 		break;
557 	case CRYPTO_BUF_MBUF:
558 		for (;;) {
559 			/*
560 			 * This uses m_copydata() for individual
561 			 * mbufs so that cc_mbuf and cc_offset are
562 			 * updated.
563 			 */
564 			remain = cc->cc_mbuf->m_len - cc->cc_offset;
565 			todo = MIN(remain, size);
566 			m_copydata(cc->cc_mbuf, cc->cc_offset, todo, dst);
567 			dst += todo;
568 			if (todo < remain) {
569 				cc->cc_offset += todo;
570 				break;
571 			}
572 			size -= todo;
573 			cc->cc_mbuf = cc->cc_mbuf->m_next;
574 			cc->cc_offset = 0;
575 			if (size == 0)
576 				break;
577 		}
578 		break;
579 	case CRYPTO_BUF_SINGLE_MBUF:
580 		MPASS(cc->cc_mbuf->m_len >= cc->cc_offset + size);
581 		m_copydata(cc->cc_mbuf, cc->cc_offset, size, dst);
582 		cc->cc_offset += size;
583 		break;
584 	case CRYPTO_BUF_VMPAGE:
585 		for (;;) {
586 			src = (char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(
587 			    *cc->cc_vmpage)) + cc->cc_offset;
588 			remain = MIN(PAGE_SIZE - cc->cc_offset, cc->cc_buf_len);
589 			todo = MIN(remain, size);
590 			memcpy(dst, src, todo);
591 			dst += todo;
592 			cc->cc_buf_len -= todo;
593 			if (todo < remain) {
594 				cc->cc_offset += todo;
595 				break;
596 			}
597 			size -= todo;
598 			cc->cc_vmpage++;
599 			cc->cc_offset = 0;
600 			if (size == 0)
601 				break;
602 		}
603 		break;
604 	case CRYPTO_BUF_UIO:
605 		for (;;) {
606 			src = (const char *)cc->cc_iov->iov_base +
607 			    cc->cc_offset;
608 			remain = cc->cc_iov->iov_len - cc->cc_offset;
609 			todo = MIN(remain, size);
610 			memcpy(dst, src, todo);
611 			dst += todo;
612 			cc->cc_buf_len -= todo;
613 			if (todo < remain) {
614 				cc->cc_offset += todo;
615 				break;
616 			}
617 			size -= todo;
618 			cc->cc_iov++;
619 			cc->cc_offset = 0;
620 			if (size == 0)
621 				break;
622 		}
623 		break;
624 	default:
625 #ifdef INVARIANTS
626 		panic("%s: invalid buffer type %d", __func__, cc->cc_type);
627 #endif
628 		break;
629 	}
630 }
631 
632 /*
633  * To avoid advancing 'cursor', make a local copy that gets advanced
634  * instead.
635  */
636 void
637 crypto_cursor_copydata_noadv(struct crypto_buffer_cursor *cc, int size,
638     void *vdst)
639 {
640 	struct crypto_buffer_cursor copy;
641 
642 	copy = *cc;
643 	crypto_cursor_copydata(&copy, size, vdst);
644 }
645 
646 /*
647  * Apply function f to the data in an iovec list starting "off" bytes from
648  * the beginning, continuing for "len" bytes.
649  */
650 static int
651 cuio_apply(struct uio *uio, int off, int len,
652     int (*f)(void *, const void *, u_int), void *arg)
653 {
654 	struct iovec *iov = uio->uio_iov;
655 	int iol __diagused = uio->uio_iovcnt;
656 	unsigned count;
657 	int rval;
658 
659 	CUIO_SKIP();
660 	while (len > 0) {
661 		KASSERT(iol >= 0, ("%s: empty", __func__));
662 		count = min(iov->iov_len - off, len);
663 		rval = (*f)(arg, ((caddr_t)iov->iov_base) + off, count);
664 		if (rval)
665 			return (rval);
666 		len -= count;
667 		off = 0;
668 		iol--;
669 		iov++;
670 	}
671 	return (0);
672 }
673 
674 void
675 crypto_copyback(struct cryptop *crp, int off, int size, const void *src)
676 {
677 	struct crypto_buffer *cb;
678 
679 	if (crp->crp_obuf.cb_type != CRYPTO_BUF_NONE)
680 		cb = &crp->crp_obuf;
681 	else
682 		cb = &crp->crp_buf;
683 	switch (cb->cb_type) {
684 	case CRYPTO_BUF_MBUF:
685 	case CRYPTO_BUF_SINGLE_MBUF:
686 		m_copyback(cb->cb_mbuf, off, size, src);
687 		break;
688 #if CRYPTO_MAY_HAVE_VMPAGE
689 	case CRYPTO_BUF_VMPAGE:
690 		MPASS(size <= cb->cb_vm_page_len);
691 		MPASS(size + off <=
692 		    cb->cb_vm_page_len + cb->cb_vm_page_offset);
693 		cvm_page_copyback(cb->cb_vm_page,
694 		    off + cb->cb_vm_page_offset, size, src);
695 		break;
696 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
697 	case CRYPTO_BUF_UIO:
698 		cuio_copyback(cb->cb_uio, off, size, src);
699 		break;
700 	case CRYPTO_BUF_CONTIG:
701 		MPASS(off + size <= cb->cb_buf_len);
702 		bcopy(src, cb->cb_buf + off, size);
703 		break;
704 	default:
705 #ifdef INVARIANTS
706 		panic("invalid crp buf type %d", cb->cb_type);
707 #endif
708 		break;
709 	}
710 }
711 
712 void
713 crypto_copydata(struct cryptop *crp, int off, int size, void *dst)
714 {
715 
716 	switch (crp->crp_buf.cb_type) {
717 	case CRYPTO_BUF_MBUF:
718 	case CRYPTO_BUF_SINGLE_MBUF:
719 		m_copydata(crp->crp_buf.cb_mbuf, off, size, dst);
720 		break;
721 #if CRYPTO_MAY_HAVE_VMPAGE
722 	case CRYPTO_BUF_VMPAGE:
723 		MPASS(size <= crp->crp_buf.cb_vm_page_len);
724 		MPASS(size + off <= crp->crp_buf.cb_vm_page_len +
725 		    crp->crp_buf.cb_vm_page_offset);
726 		cvm_page_copydata(crp->crp_buf.cb_vm_page,
727 		    off + crp->crp_buf.cb_vm_page_offset, size, dst);
728 		break;
729 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
730 	case CRYPTO_BUF_UIO:
731 		cuio_copydata(crp->crp_buf.cb_uio, off, size, dst);
732 		break;
733 	case CRYPTO_BUF_CONTIG:
734 		MPASS(off + size <= crp->crp_buf.cb_buf_len);
735 		bcopy(crp->crp_buf.cb_buf + off, dst, size);
736 		break;
737 	default:
738 #ifdef INVARIANTS
739 		panic("invalid crp buf type %d", crp->crp_buf.cb_type);
740 #endif
741 		break;
742 	}
743 }
744 
745 int
746 crypto_apply_buf(struct crypto_buffer *cb, int off, int len,
747     int (*f)(void *, const void *, u_int), void *arg)
748 {
749 	int error;
750 
751 	switch (cb->cb_type) {
752 	case CRYPTO_BUF_MBUF:
753 	case CRYPTO_BUF_SINGLE_MBUF:
754 		error = m_apply(cb->cb_mbuf, off, len,
755 		    (int (*)(void *, void *, u_int))f, arg);
756 		break;
757 	case CRYPTO_BUF_UIO:
758 		error = cuio_apply(cb->cb_uio, off, len, f, arg);
759 		break;
760 #if CRYPTO_MAY_HAVE_VMPAGE
761 	case CRYPTO_BUF_VMPAGE:
762 		error = cvm_page_apply(cb->cb_vm_page,
763 		    off + cb->cb_vm_page_offset, len, f, arg);
764 		break;
765 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
766 	case CRYPTO_BUF_CONTIG:
767 		MPASS(off + len <= cb->cb_buf_len);
768 		error = (*f)(arg, cb->cb_buf + off, len);
769 		break;
770 	default:
771 #ifdef INVARIANTS
772 		panic("invalid crypto buf type %d", cb->cb_type);
773 #endif
774 		error = 0;
775 		break;
776 	}
777 	return (error);
778 }
779 
780 int
781 crypto_apply(struct cryptop *crp, int off, int len,
782     int (*f)(void *, const void *, u_int), void *arg)
783 {
784 	return (crypto_apply_buf(&crp->crp_buf, off, len, f, arg));
785 }
786 
787 static inline void *
788 m_contiguous_subsegment(struct mbuf *m, size_t skip, size_t len)
789 {
790 	int rel_off;
791 
792 	MPASS(skip <= INT_MAX);
793 
794 	m = m_getptr(m, (int)skip, &rel_off);
795 	if (m == NULL)
796 		return (NULL);
797 
798 	MPASS(rel_off >= 0);
799 	skip = rel_off;
800 	if (skip + len > m->m_len)
801 		return (NULL);
802 
803 	if (m->m_flags & M_EXTPG)
804 		return (m_epg_contiguous_subsegment(m, skip, len));
805 	return (mtod(m, char*) + skip);
806 }
807 
808 static inline void *
809 cuio_contiguous_segment(struct uio *uio, size_t skip, size_t len)
810 {
811 	int rel_off, idx;
812 
813 	MPASS(skip <= INT_MAX);
814 	idx = cuio_getptr(uio, (int)skip, &rel_off);
815 	if (idx < 0)
816 		return (NULL);
817 
818 	MPASS(rel_off >= 0);
819 	skip = rel_off;
820 	if (skip + len > uio->uio_iov[idx].iov_len)
821 		return (NULL);
822 	return ((char *)uio->uio_iov[idx].iov_base + skip);
823 }
824 
825 void *
826 crypto_buffer_contiguous_subsegment(struct crypto_buffer *cb, size_t skip,
827     size_t len)
828 {
829 
830 	switch (cb->cb_type) {
831 	case CRYPTO_BUF_MBUF:
832 	case CRYPTO_BUF_SINGLE_MBUF:
833 		return (m_contiguous_subsegment(cb->cb_mbuf, skip, len));
834 	case CRYPTO_BUF_UIO:
835 		return (cuio_contiguous_segment(cb->cb_uio, skip, len));
836 #if CRYPTO_MAY_HAVE_VMPAGE
837 	case CRYPTO_BUF_VMPAGE:
838 		MPASS(skip + len <= cb->cb_vm_page_len);
839 		return (cvm_page_contiguous_segment(cb->cb_vm_page,
840 		    skip + cb->cb_vm_page_offset, len));
841 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
842 	case CRYPTO_BUF_CONTIG:
843 		MPASS(skip + len <= cb->cb_buf_len);
844 		return (cb->cb_buf + skip);
845 	default:
846 #ifdef INVARIANTS
847 		panic("invalid crp buf type %d", cb->cb_type);
848 #endif
849 		return (NULL);
850 	}
851 }
852 
853 void *
854 crypto_contiguous_subsegment(struct cryptop *crp, size_t skip, size_t len)
855 {
856 	return (crypto_buffer_contiguous_subsegment(&crp->crp_buf, skip, len));
857 }
858