xref: /freebsd/sys/opencrypto/criov.c (revision 718d4a1d5643c2faf409001320c3fd64aae57638)
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/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/proc.h>
36 #include <sys/errno.h>
37 #include <sys/malloc.h>
38 #include <sys/kernel.h>
39 #include <sys/mbuf.h>
40 #include <sys/uio.h>
41 #include <sys/limits.h>
42 #include <sys/lock.h>
43 #include <sys/sdt.h>
44 
45 #include <machine/vmparam.h>
46 
47 #include <vm/vm.h>
48 #include <vm/vm_page.h>
49 #include <vm/pmap.h>
50 
51 #include <opencrypto/cryptodev.h>
52 
53 SDT_PROVIDER_DECLARE(opencrypto);
54 
55 /*
56  * These macros are only for avoiding code duplication, as we need to skip
57  * given number of bytes in the same way in several functions below.
58  */
59 #define	CUIO_SKIP()	do {						\
60 	KASSERT(off >= 0, ("%s: off %d < 0", __func__, off));		\
61 	KASSERT(len >= 0, ("%s: len %d < 0", __func__, len));		\
62 	while (off > 0) {						\
63 		KASSERT(iol >= 0, ("%s: empty in skip", __func__));	\
64 		if (off < iov->iov_len)					\
65 			break;						\
66 		off -= iov->iov_len;					\
67 		iol--;							\
68 		iov++;							\
69 	}								\
70 } while (0)
71 
72 #define CVM_PAGE_SKIP()	do {					\
73 	KASSERT(off >= 0, ("%s: off %d < 0", __func__, off));		\
74 	KASSERT(len >= 0, ("%s: len %d < 0", __func__, len));		\
75 	while (off > 0) {						\
76 		if (off < PAGE_SIZE)					\
77 			break;						\
78 		processed += PAGE_SIZE - off;				\
79 		off -= PAGE_SIZE - off;					\
80 		pages++;						\
81 	}								\
82 } while (0)
83 
84 static void
85 cuio_copydata(struct uio* uio, int off, int len, caddr_t cp)
86 {
87 	struct iovec *iov = uio->uio_iov;
88 	int iol __diagused = uio->uio_iovcnt;
89 	unsigned count;
90 
91 	CUIO_SKIP();
92 	while (len > 0) {
93 		KASSERT(iol >= 0, ("%s: empty", __func__));
94 		count = min(iov->iov_len - off, len);
95 		bcopy(((caddr_t)iov->iov_base) + off, cp, count);
96 		len -= count;
97 		cp += count;
98 		off = 0;
99 		iol--;
100 		iov++;
101 	}
102 }
103 
104 static void
105 cuio_copyback(struct uio* uio, int off, int len, c_caddr_t cp)
106 {
107 	struct iovec *iov = uio->uio_iov;
108 	int iol __diagused = uio->uio_iovcnt;
109 	unsigned count;
110 
111 	CUIO_SKIP();
112 	while (len > 0) {
113 		KASSERT(iol >= 0, ("%s: empty", __func__));
114 		count = min(iov->iov_len - off, len);
115 		bcopy(cp, ((caddr_t)iov->iov_base) + off, count);
116 		len -= count;
117 		cp += count;
118 		off = 0;
119 		iol--;
120 		iov++;
121 	}
122 }
123 
124 /*
125  * Return the index and offset of location in iovec list.
126  */
127 static int
128 cuio_getptr(struct uio *uio, int loc, int *off)
129 {
130 	int ind, len;
131 
132 	ind = 0;
133 	while (loc >= 0 && ind < uio->uio_iovcnt) {
134 		len = uio->uio_iov[ind].iov_len;
135 		if (len > loc) {
136 	    		*off = loc;
137 	    		return (ind);
138 		}
139 		loc -= len;
140 		ind++;
141 	}
142 
143 	if (ind > 0 && loc == 0) {
144 		ind--;
145 		*off = uio->uio_iov[ind].iov_len;
146 		return (ind);
147 	}
148 
149 	return (-1);
150 }
151 
152 #if CRYPTO_MAY_HAVE_VMPAGE
153 /*
154  * Apply function f to the data in a vm_page_t list starting "off" bytes from
155  * the beginning, continuing for "len" bytes.
156  */
157 static int
158 cvm_page_apply(vm_page_t *pages, int off, int len,
159     int (*f)(void *, const void *, u_int), void *arg)
160 {
161 	int processed __unused;
162 	unsigned count;
163 	int rval;
164 
165 	processed = 0;
166 	CVM_PAGE_SKIP();
167 	while (len > 0) {
168 		char *kaddr = (char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(*pages));
169 		count = min(PAGE_SIZE - off, len);
170 		rval = (*f)(arg, kaddr + off, count);
171 		if (rval)
172 			return (rval);
173 		len -= count;
174 		processed += count;
175 		off = 0;
176 		pages++;
177 	}
178 	return (0);
179 }
180 
181 static inline void *
182 cvm_page_contiguous_segment(vm_page_t *pages, size_t skip, int len)
183 {
184 	if ((skip + len - 1) / PAGE_SIZE > skip / PAGE_SIZE)
185 		return (NULL);
186 
187 	pages += (skip / PAGE_SIZE);
188 	skip -= rounddown(skip, PAGE_SIZE);
189 	return (((char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(*pages))) + skip);
190 }
191 
192 /*
193  * Copy len bytes of data from the vm_page_t array, skipping the first off
194  * bytes, into the pointer cp.  Return the number of bytes skipped and copied.
195  * Does not verify the length of the array.
196  */
197 static int
198 cvm_page_copyback(vm_page_t *pages, int off, int len, c_caddr_t cp)
199 {
200 	int processed = 0;
201 	unsigned count;
202 
203 	CVM_PAGE_SKIP();
204 	while (len > 0) {
205 		count = min(PAGE_SIZE - off, len);
206 		bcopy(cp, (char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(*pages)) + off,
207 		    count);
208 		len -= count;
209 		cp += count;
210 		processed += count;
211 		off = 0;
212 		pages++;
213 	}
214 	return (processed);
215 }
216 
217 /*
218  * Copy len bytes of data from the pointer cp into the vm_page_t array,
219  * skipping the first off bytes, Return the number of bytes skipped and copied.
220  * Does not verify the length of the array.
221  */
222 static int
223 cvm_page_copydata(vm_page_t *pages, int off, int len, caddr_t cp)
224 {
225 	int processed = 0;
226 	unsigned count;
227 
228 	CVM_PAGE_SKIP();
229 	while (len > 0) {
230 		count = min(PAGE_SIZE - off, len);
231 		bcopy(((char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(*pages)) + off), cp,
232 		    count);
233 		len -= count;
234 		cp += count;
235 		processed += count;
236 		off = 0;
237 		pages++;
238 	}
239 	return processed;
240 }
241 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
242 
243 /*
244  * Given a starting page in an m_epg, determine the length of the
245  * current physically contiguous segment.
246  */
247 static __inline size_t
248 m_epg_pages_extent(struct mbuf *m, int idx, u_int pglen)
249 {
250 	size_t len;
251 	u_int i;
252 
253 	len = pglen;
254 	for (i = idx + 1; i < m->m_epg_npgs; i++) {
255 		if (m->m_epg_pa[i - 1] + PAGE_SIZE != m->m_epg_pa[i])
256 			break;
257 		len += m_epg_pagelen(m, i, 0);
258 	}
259 	return (len);
260 }
261 
262 static void *
263 m_epg_segment(struct mbuf *m, size_t offset, size_t *len)
264 {
265 	u_int i, pglen, pgoff;
266 
267 	offset += mtod(m, vm_offset_t);
268 	if (offset < m->m_epg_hdrlen) {
269 		*len = m->m_epg_hdrlen - offset;
270 		return (m->m_epg_hdr + offset);
271 	}
272 	offset -= m->m_epg_hdrlen;
273 	pgoff = m->m_epg_1st_off;
274 	for (i = 0; i < m->m_epg_npgs; i++) {
275 		pglen = m_epg_pagelen(m, i, pgoff);
276 		if (offset < pglen) {
277 			*len = m_epg_pages_extent(m, i, pglen) - offset;
278 			return ((void *)PHYS_TO_DMAP(m->m_epg_pa[i] + pgoff +
279 			    offset));
280 		}
281 		offset -= pglen;
282 		pgoff = 0;
283 	}
284 	KASSERT(offset <= m->m_epg_trllen, ("%s: offset beyond trailer",
285 	    __func__));
286 	*len = m->m_epg_trllen - offset;
287 	return (m->m_epg_trail + offset);
288 }
289 
290 static __inline void *
291 m_epg_contiguous_subsegment(struct mbuf *m, size_t skip, size_t len)
292 {
293 	void *base;
294 	size_t seglen;
295 
296 	base = m_epg_segment(m, skip, &seglen);
297 	if (len > seglen)
298 		return (NULL);
299 	return (base);
300 }
301 
302 void
303 crypto_cursor_init(struct crypto_buffer_cursor *cc,
304     const struct crypto_buffer *cb)
305 {
306 	memset(cc, 0, sizeof(*cc));
307 	cc->cc_type = cb->cb_type;
308 	switch (cc->cc_type) {
309 	case CRYPTO_BUF_CONTIG:
310 		cc->cc_buf = cb->cb_buf;
311 		cc->cc_buf_len = cb->cb_buf_len;
312 		break;
313 	case CRYPTO_BUF_MBUF:
314 	case CRYPTO_BUF_SINGLE_MBUF:
315 		cc->cc_mbuf = cb->cb_mbuf;
316 		break;
317 	case CRYPTO_BUF_VMPAGE:
318 		cc->cc_vmpage = cb->cb_vm_page;
319 		cc->cc_buf_len = cb->cb_vm_page_len;
320 		cc->cc_offset = cb->cb_vm_page_offset;
321 		break;
322 	case CRYPTO_BUF_UIO:
323 		cc->cc_iov = cb->cb_uio->uio_iov;
324 		cc->cc_buf_len = cb->cb_uio->uio_resid;
325 		break;
326 	default:
327 #ifdef INVARIANTS
328 		panic("%s: invalid buffer type %d", __func__, cb->cb_type);
329 #endif
330 		break;
331 	}
332 }
333 
334 SDT_PROBE_DEFINE2(opencrypto, criov, cursor_advance, vmpage, "struct crypto_buffer_cursor*", "size_t");
335 
336 void
337 crypto_cursor_advance(struct crypto_buffer_cursor *cc, size_t amount)
338 {
339 	size_t remain;
340 
341 	switch (cc->cc_type) {
342 	case CRYPTO_BUF_CONTIG:
343 		MPASS(cc->cc_buf_len >= amount);
344 		cc->cc_buf += amount;
345 		cc->cc_buf_len -= amount;
346 		break;
347 	case CRYPTO_BUF_MBUF:
348 		for (;;) {
349 			remain = cc->cc_mbuf->m_len - cc->cc_offset;
350 			if (amount < remain) {
351 				cc->cc_offset += amount;
352 				break;
353 			}
354 			amount -= remain;
355 			cc->cc_mbuf = cc->cc_mbuf->m_next;
356 			cc->cc_offset = 0;
357 			if (amount == 0)
358 				break;
359 		}
360 		break;
361 	case CRYPTO_BUF_SINGLE_MBUF:
362 		MPASS(cc->cc_mbuf->m_len >= cc->cc_offset + amount);
363 		cc->cc_offset += amount;
364 		break;
365 	case CRYPTO_BUF_VMPAGE:
366 		for (;;) {
367 			SDT_PROBE2(opencrypto, criov, cursor_advance, vmpage,
368 			    cc, amount);
369 			remain = MIN(PAGE_SIZE - cc->cc_offset, cc->cc_buf_len);
370 			if (amount < remain) {
371 				cc->cc_buf_len -= amount;
372 				cc->cc_offset += amount;
373 				break;
374 			}
375 			cc->cc_buf_len -= remain;
376 			amount -= remain;
377 			cc->cc_vmpage++;
378 			cc->cc_offset = 0;
379 			if (amount == 0 || cc->cc_buf_len == 0)
380 				break;
381 		}
382 		break;
383 	case CRYPTO_BUF_UIO:
384 		for (;;) {
385 			remain = cc->cc_iov->iov_len - cc->cc_offset;
386 			if (amount < remain) {
387 				cc->cc_offset += amount;
388 				break;
389 			}
390 			cc->cc_buf_len -= remain;
391 			amount -= remain;
392 			cc->cc_iov++;
393 			cc->cc_offset = 0;
394 			if (amount == 0)
395 				break;
396 		}
397 		break;
398 	default:
399 #ifdef INVARIANTS
400 		panic("%s: invalid buffer type %d", __func__, cc->cc_type);
401 #endif
402 		break;
403 	}
404 }
405 
406 void *
407 crypto_cursor_segment(struct crypto_buffer_cursor *cc, size_t *len)
408 {
409 	switch (cc->cc_type) {
410 	case CRYPTO_BUF_CONTIG:
411 	case CRYPTO_BUF_UIO:
412 	case CRYPTO_BUF_VMPAGE:
413 		if (cc->cc_buf_len == 0) {
414 			*len = 0;
415 			return (NULL);
416 		}
417 		break;
418 	case CRYPTO_BUF_MBUF:
419 	case CRYPTO_BUF_SINGLE_MBUF:
420 		if (cc->cc_mbuf == NULL) {
421 			*len = 0;
422 			return (NULL);
423 		}
424 		break;
425 	default:
426 #ifdef INVARIANTS
427 		panic("%s: invalid buffer type %d", __func__, cc->cc_type);
428 #endif
429 		*len = 0;
430 		return (NULL);
431 	}
432 
433 	switch (cc->cc_type) {
434 	case CRYPTO_BUF_CONTIG:
435 		*len = cc->cc_buf_len;
436 		return (cc->cc_buf);
437 	case CRYPTO_BUF_MBUF:
438 	case CRYPTO_BUF_SINGLE_MBUF:
439 		if (cc->cc_mbuf->m_flags & M_EXTPG)
440 			return (m_epg_segment(cc->cc_mbuf, cc->cc_offset, len));
441 		*len = cc->cc_mbuf->m_len - cc->cc_offset;
442 		return (mtod(cc->cc_mbuf, char *) + cc->cc_offset);
443 	case CRYPTO_BUF_VMPAGE:
444 		*len = PAGE_SIZE - cc->cc_offset;
445 		return ((char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(
446 		    *cc->cc_vmpage)) + cc->cc_offset);
447 	case CRYPTO_BUF_UIO:
448 		*len = cc->cc_iov->iov_len - cc->cc_offset;
449 		return ((char *)cc->cc_iov->iov_base + cc->cc_offset);
450 	default:
451 		__assert_unreachable();
452 	}
453 }
454 
455 void
456 crypto_cursor_copyback(struct crypto_buffer_cursor *cc, int size,
457     const void *vsrc)
458 {
459 	size_t remain, todo;
460 	const char *src;
461 	char *dst;
462 
463 	src = vsrc;
464 	switch (cc->cc_type) {
465 	case CRYPTO_BUF_CONTIG:
466 		MPASS(cc->cc_buf_len >= size);
467 		memcpy(cc->cc_buf, src, size);
468 		cc->cc_buf += size;
469 		cc->cc_buf_len -= size;
470 		break;
471 	case CRYPTO_BUF_MBUF:
472 		for (;;) {
473 			/*
474 			 * This uses m_copyback() for individual
475 			 * mbufs so that cc_mbuf and cc_offset are
476 			 * updated.
477 			 */
478 			remain = cc->cc_mbuf->m_len - cc->cc_offset;
479 			todo = MIN(remain, size);
480 			m_copyback(cc->cc_mbuf, cc->cc_offset, todo, src);
481 			src += todo;
482 			if (todo < remain) {
483 				cc->cc_offset += todo;
484 				break;
485 			}
486 			size -= todo;
487 			cc->cc_mbuf = cc->cc_mbuf->m_next;
488 			cc->cc_offset = 0;
489 			if (size == 0)
490 				break;
491 		}
492 		break;
493 	case CRYPTO_BUF_SINGLE_MBUF:
494 		MPASS(cc->cc_mbuf->m_len >= cc->cc_offset + size);
495 		m_copyback(cc->cc_mbuf, cc->cc_offset, size, src);
496 		cc->cc_offset += size;
497 		break;
498 	case CRYPTO_BUF_VMPAGE:
499 		for (;;) {
500 			dst = (char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(
501 			    *cc->cc_vmpage)) + cc->cc_offset;
502 			remain = MIN(PAGE_SIZE - cc->cc_offset, cc->cc_buf_len);
503 			todo = MIN(remain, size);
504 			memcpy(dst, src, todo);
505 			src += todo;
506 			cc->cc_buf_len -= todo;
507 			if (todo < remain) {
508 				cc->cc_offset += todo;
509 				break;
510 			}
511 			size -= todo;
512 			cc->cc_vmpage++;
513 			cc->cc_offset = 0;
514 			if (size == 0)
515 				break;
516 		}
517 		break;
518 	case CRYPTO_BUF_UIO:
519 		for (;;) {
520 			dst = (char *)cc->cc_iov->iov_base + cc->cc_offset;
521 			remain = cc->cc_iov->iov_len - cc->cc_offset;
522 			todo = MIN(remain, size);
523 			memcpy(dst, src, todo);
524 			src += todo;
525 			cc->cc_buf_len -= todo;
526 			if (todo < remain) {
527 				cc->cc_offset += todo;
528 				break;
529 			}
530 			size -= todo;
531 			cc->cc_iov++;
532 			cc->cc_offset = 0;
533 			if (size == 0)
534 				break;
535 		}
536 		break;
537 	default:
538 #ifdef INVARIANTS
539 		panic("%s: invalid buffer type %d", __func__, cc->cc_type);
540 #endif
541 		break;
542 	}
543 }
544 
545 void
546 crypto_cursor_copydata(struct crypto_buffer_cursor *cc, int size, void *vdst)
547 {
548 	size_t remain, todo;
549 	const char *src;
550 	char *dst;
551 
552 	dst = vdst;
553 	switch (cc->cc_type) {
554 	case CRYPTO_BUF_CONTIG:
555 		MPASS(cc->cc_buf_len >= size);
556 		memcpy(dst, cc->cc_buf, size);
557 		cc->cc_buf += size;
558 		cc->cc_buf_len -= size;
559 		break;
560 	case CRYPTO_BUF_MBUF:
561 		for (;;) {
562 			/*
563 			 * This uses m_copydata() for individual
564 			 * mbufs so that cc_mbuf and cc_offset are
565 			 * updated.
566 			 */
567 			remain = cc->cc_mbuf->m_len - cc->cc_offset;
568 			todo = MIN(remain, size);
569 			m_copydata(cc->cc_mbuf, cc->cc_offset, todo, dst);
570 			dst += todo;
571 			if (todo < remain) {
572 				cc->cc_offset += todo;
573 				break;
574 			}
575 			size -= todo;
576 			cc->cc_mbuf = cc->cc_mbuf->m_next;
577 			cc->cc_offset = 0;
578 			if (size == 0)
579 				break;
580 		}
581 		break;
582 	case CRYPTO_BUF_SINGLE_MBUF:
583 		MPASS(cc->cc_mbuf->m_len >= cc->cc_offset + size);
584 		m_copydata(cc->cc_mbuf, cc->cc_offset, size, dst);
585 		cc->cc_offset += size;
586 		break;
587 	case CRYPTO_BUF_VMPAGE:
588 		for (;;) {
589 			src = (char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(
590 			    *cc->cc_vmpage)) + cc->cc_offset;
591 			remain = MIN(PAGE_SIZE - cc->cc_offset, cc->cc_buf_len);
592 			todo = MIN(remain, size);
593 			memcpy(dst, src, todo);
594 			src += todo;
595 			cc->cc_buf_len -= todo;
596 			if (todo < remain) {
597 				cc->cc_offset += todo;
598 				break;
599 			}
600 			size -= todo;
601 			cc->cc_vmpage++;
602 			cc->cc_offset = 0;
603 			if (size == 0)
604 				break;
605 		}
606 		break;
607 	case CRYPTO_BUF_UIO:
608 		for (;;) {
609 			src = (const char *)cc->cc_iov->iov_base +
610 			    cc->cc_offset;
611 			remain = cc->cc_iov->iov_len - cc->cc_offset;
612 			todo = MIN(remain, size);
613 			memcpy(dst, src, todo);
614 			dst += todo;
615 			cc->cc_buf_len -= todo;
616 			if (todo < remain) {
617 				cc->cc_offset += todo;
618 				break;
619 			}
620 			size -= todo;
621 			cc->cc_iov++;
622 			cc->cc_offset = 0;
623 			if (size == 0)
624 				break;
625 		}
626 		break;
627 	default:
628 #ifdef INVARIANTS
629 		panic("%s: invalid buffer type %d", __func__, cc->cc_type);
630 #endif
631 		break;
632 	}
633 }
634 
635 /*
636  * To avoid advancing 'cursor', make a local copy that gets advanced
637  * instead.
638  */
639 void
640 crypto_cursor_copydata_noadv(struct crypto_buffer_cursor *cc, int size,
641     void *vdst)
642 {
643 	struct crypto_buffer_cursor copy;
644 
645 	copy = *cc;
646 	crypto_cursor_copydata(&copy, size, vdst);
647 }
648 
649 /*
650  * Apply function f to the data in an iovec list starting "off" bytes from
651  * the beginning, continuing for "len" bytes.
652  */
653 static int
654 cuio_apply(struct uio *uio, int off, int len,
655     int (*f)(void *, const void *, u_int), void *arg)
656 {
657 	struct iovec *iov = uio->uio_iov;
658 	int iol __diagused = uio->uio_iovcnt;
659 	unsigned count;
660 	int rval;
661 
662 	CUIO_SKIP();
663 	while (len > 0) {
664 		KASSERT(iol >= 0, ("%s: empty", __func__));
665 		count = min(iov->iov_len - off, len);
666 		rval = (*f)(arg, ((caddr_t)iov->iov_base) + off, count);
667 		if (rval)
668 			return (rval);
669 		len -= count;
670 		off = 0;
671 		iol--;
672 		iov++;
673 	}
674 	return (0);
675 }
676 
677 void
678 crypto_copyback(struct cryptop *crp, int off, int size, const void *src)
679 {
680 	struct crypto_buffer *cb;
681 
682 	if (crp->crp_obuf.cb_type != CRYPTO_BUF_NONE)
683 		cb = &crp->crp_obuf;
684 	else
685 		cb = &crp->crp_buf;
686 	switch (cb->cb_type) {
687 	case CRYPTO_BUF_MBUF:
688 	case CRYPTO_BUF_SINGLE_MBUF:
689 		m_copyback(cb->cb_mbuf, off, size, src);
690 		break;
691 #if CRYPTO_MAY_HAVE_VMPAGE
692 	case CRYPTO_BUF_VMPAGE:
693 		MPASS(size <= cb->cb_vm_page_len);
694 		MPASS(size + off <=
695 		    cb->cb_vm_page_len + cb->cb_vm_page_offset);
696 		cvm_page_copyback(cb->cb_vm_page,
697 		    off + cb->cb_vm_page_offset, size, src);
698 		break;
699 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
700 	case CRYPTO_BUF_UIO:
701 		cuio_copyback(cb->cb_uio, off, size, src);
702 		break;
703 	case CRYPTO_BUF_CONTIG:
704 		MPASS(off + size <= cb->cb_buf_len);
705 		bcopy(src, cb->cb_buf + off, size);
706 		break;
707 	default:
708 #ifdef INVARIANTS
709 		panic("invalid crp buf type %d", cb->cb_type);
710 #endif
711 		break;
712 	}
713 }
714 
715 void
716 crypto_copydata(struct cryptop *crp, int off, int size, void *dst)
717 {
718 
719 	switch (crp->crp_buf.cb_type) {
720 	case CRYPTO_BUF_MBUF:
721 	case CRYPTO_BUF_SINGLE_MBUF:
722 		m_copydata(crp->crp_buf.cb_mbuf, off, size, dst);
723 		break;
724 #if CRYPTO_MAY_HAVE_VMPAGE
725 	case CRYPTO_BUF_VMPAGE:
726 		MPASS(size <= crp->crp_buf.cb_vm_page_len);
727 		MPASS(size + off <= crp->crp_buf.cb_vm_page_len +
728 		    crp->crp_buf.cb_vm_page_offset);
729 		cvm_page_copydata(crp->crp_buf.cb_vm_page,
730 		    off + crp->crp_buf.cb_vm_page_offset, size, dst);
731 		break;
732 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
733 	case CRYPTO_BUF_UIO:
734 		cuio_copydata(crp->crp_buf.cb_uio, off, size, dst);
735 		break;
736 	case CRYPTO_BUF_CONTIG:
737 		MPASS(off + size <= crp->crp_buf.cb_buf_len);
738 		bcopy(crp->crp_buf.cb_buf + off, dst, size);
739 		break;
740 	default:
741 #ifdef INVARIANTS
742 		panic("invalid crp buf type %d", crp->crp_buf.cb_type);
743 #endif
744 		break;
745 	}
746 }
747 
748 int
749 crypto_apply_buf(struct crypto_buffer *cb, int off, int len,
750     int (*f)(void *, const void *, u_int), void *arg)
751 {
752 	int error;
753 
754 	switch (cb->cb_type) {
755 	case CRYPTO_BUF_MBUF:
756 	case CRYPTO_BUF_SINGLE_MBUF:
757 		error = m_apply(cb->cb_mbuf, off, len,
758 		    (int (*)(void *, void *, u_int))f, arg);
759 		break;
760 	case CRYPTO_BUF_UIO:
761 		error = cuio_apply(cb->cb_uio, off, len, f, arg);
762 		break;
763 #if CRYPTO_MAY_HAVE_VMPAGE
764 	case CRYPTO_BUF_VMPAGE:
765 		error = cvm_page_apply(cb->cb_vm_page,
766 		    off + cb->cb_vm_page_offset, len, f, arg);
767 		break;
768 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
769 	case CRYPTO_BUF_CONTIG:
770 		MPASS(off + len <= cb->cb_buf_len);
771 		error = (*f)(arg, cb->cb_buf + off, len);
772 		break;
773 	default:
774 #ifdef INVARIANTS
775 		panic("invalid crypto buf type %d", cb->cb_type);
776 #endif
777 		error = 0;
778 		break;
779 	}
780 	return (error);
781 }
782 
783 int
784 crypto_apply(struct cryptop *crp, int off, int len,
785     int (*f)(void *, const void *, u_int), void *arg)
786 {
787 	return (crypto_apply_buf(&crp->crp_buf, off, len, f, arg));
788 }
789 
790 static inline void *
791 m_contiguous_subsegment(struct mbuf *m, size_t skip, size_t len)
792 {
793 	int rel_off;
794 
795 	MPASS(skip <= INT_MAX);
796 
797 	m = m_getptr(m, (int)skip, &rel_off);
798 	if (m == NULL)
799 		return (NULL);
800 
801 	MPASS(rel_off >= 0);
802 	skip = rel_off;
803 	if (skip + len > m->m_len)
804 		return (NULL);
805 
806 	if (m->m_flags & M_EXTPG)
807 		return (m_epg_contiguous_subsegment(m, skip, len));
808 	return (mtod(m, char*) + skip);
809 }
810 
811 static inline void *
812 cuio_contiguous_segment(struct uio *uio, size_t skip, size_t len)
813 {
814 	int rel_off, idx;
815 
816 	MPASS(skip <= INT_MAX);
817 	idx = cuio_getptr(uio, (int)skip, &rel_off);
818 	if (idx < 0)
819 		return (NULL);
820 
821 	MPASS(rel_off >= 0);
822 	skip = rel_off;
823 	if (skip + len > uio->uio_iov[idx].iov_len)
824 		return (NULL);
825 	return ((char *)uio->uio_iov[idx].iov_base + skip);
826 }
827 
828 void *
829 crypto_buffer_contiguous_subsegment(struct crypto_buffer *cb, size_t skip,
830     size_t len)
831 {
832 
833 	switch (cb->cb_type) {
834 	case CRYPTO_BUF_MBUF:
835 	case CRYPTO_BUF_SINGLE_MBUF:
836 		return (m_contiguous_subsegment(cb->cb_mbuf, skip, len));
837 	case CRYPTO_BUF_UIO:
838 		return (cuio_contiguous_segment(cb->cb_uio, skip, len));
839 #if CRYPTO_MAY_HAVE_VMPAGE
840 	case CRYPTO_BUF_VMPAGE:
841 		MPASS(skip + len <= cb->cb_vm_page_len);
842 		return (cvm_page_contiguous_segment(cb->cb_vm_page,
843 		    skip + cb->cb_vm_page_offset, len));
844 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
845 	case CRYPTO_BUF_CONTIG:
846 		MPASS(skip + len <= cb->cb_buf_len);
847 		return (cb->cb_buf + skip);
848 	default:
849 #ifdef INVARIANTS
850 		panic("invalid crp buf type %d", cb->cb_type);
851 #endif
852 		return (NULL);
853 	}
854 }
855 
856 void *
857 crypto_contiguous_subsegment(struct cryptop *crp, size_t skip, size_t len)
858 {
859 	return (crypto_buffer_contiguous_subsegment(&crp->crp_buf, skip, len));
860 }
861