xref: /freebsd-13-stable/sys/opencrypto/criov.c (revision 3bc80996974a61a4223eae4c1ccd47b6ee32a48a)
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 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/proc.h>
34 #include <sys/errno.h>
35 #include <sys/malloc.h>
36 #include <sys/kernel.h>
37 #include <sys/mbuf.h>
38 #include <sys/uio.h>
39 #include <sys/limits.h>
40 #include <sys/lock.h>
41 #include <sys/sdt.h>
42 
43 #include <machine/vmparam.h>
44 
45 #include <vm/vm.h>
46 #include <vm/vm_page.h>
47 #include <vm/pmap.h>
48 
49 #include <opencrypto/cryptodev.h>
50 
51 SDT_PROVIDER_DECLARE(opencrypto);
52 
53 /*
54  * These macros are only for avoiding code duplication, as we need to skip
55  * given number of bytes in the same way in several functions below.
56  */
57 #define	CUIO_SKIP()	do {						\
58 	KASSERT(off >= 0, ("%s: off %d < 0", __func__, off));		\
59 	KASSERT(len >= 0, ("%s: len %d < 0", __func__, len));		\
60 	while (off > 0) {						\
61 		KASSERT(iol >= 0, ("%s: empty in skip", __func__));	\
62 		if (off < iov->iov_len)					\
63 			break;						\
64 		off -= iov->iov_len;					\
65 		iol--;							\
66 		iov++;							\
67 	}								\
68 } while (0)
69 
70 #define CVM_PAGE_SKIP()	do {					\
71 	KASSERT(off >= 0, ("%s: off %d < 0", __func__, off));		\
72 	KASSERT(len >= 0, ("%s: len %d < 0", __func__, len));		\
73 	while (off > 0) {						\
74 		if (off < PAGE_SIZE)					\
75 			break;						\
76 		processed += PAGE_SIZE - off;				\
77 		off -= PAGE_SIZE - off;					\
78 		pages++;						\
79 	}								\
80 } while (0)
81 
82 static void
cuio_copydata(struct uio * uio,int off,int len,caddr_t cp)83 cuio_copydata(struct uio* uio, int off, int len, caddr_t cp)
84 {
85 	struct iovec *iov = uio->uio_iov;
86 	int iol __diagused = uio->uio_iovcnt;
87 	unsigned count;
88 
89 	CUIO_SKIP();
90 	while (len > 0) {
91 		KASSERT(iol >= 0, ("%s: empty", __func__));
92 		count = min(iov->iov_len - off, len);
93 		bcopy(((caddr_t)iov->iov_base) + off, cp, count);
94 		len -= count;
95 		cp += count;
96 		off = 0;
97 		iol--;
98 		iov++;
99 	}
100 }
101 
102 static void
cuio_copyback(struct uio * uio,int off,int len,c_caddr_t cp)103 cuio_copyback(struct uio* uio, int off, int len, c_caddr_t cp)
104 {
105 	struct iovec *iov = uio->uio_iov;
106 	int iol __diagused = uio->uio_iovcnt;
107 	unsigned count;
108 
109 	CUIO_SKIP();
110 	while (len > 0) {
111 		KASSERT(iol >= 0, ("%s: empty", __func__));
112 		count = min(iov->iov_len - off, len);
113 		bcopy(cp, ((caddr_t)iov->iov_base) + off, count);
114 		len -= count;
115 		cp += count;
116 		off = 0;
117 		iol--;
118 		iov++;
119 	}
120 }
121 
122 /*
123  * Return the index and offset of location in iovec list.
124  */
125 static int
cuio_getptr(struct uio * uio,int loc,int * off)126 cuio_getptr(struct uio *uio, int loc, int *off)
127 {
128 	int ind, len;
129 
130 	ind = 0;
131 	while (loc >= 0 && ind < uio->uio_iovcnt) {
132 		len = uio->uio_iov[ind].iov_len;
133 		if (len > loc) {
134 	    		*off = loc;
135 	    		return (ind);
136 		}
137 		loc -= len;
138 		ind++;
139 	}
140 
141 	if (ind > 0 && loc == 0) {
142 		ind--;
143 		*off = uio->uio_iov[ind].iov_len;
144 		return (ind);
145 	}
146 
147 	return (-1);
148 }
149 
150 #if CRYPTO_MAY_HAVE_VMPAGE
151 /*
152  * Apply function f to the data in a vm_page_t list starting "off" bytes from
153  * the beginning, continuing for "len" bytes.
154  */
155 static int
cvm_page_apply(vm_page_t * pages,int off,int len,int (* f)(void *,const void *,u_int),void * arg)156 cvm_page_apply(vm_page_t *pages, int off, int len,
157     int (*f)(void *, const void *, u_int), void *arg)
158 {
159 	int processed = 0;
160 	unsigned count;
161 	int rval;
162 
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 *
cvm_page_contiguous_segment(vm_page_t * pages,size_t skip,int len)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
cvm_page_copyback(vm_page_t * pages,int off,int len,c_caddr_t cp)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
cvm_page_copydata(vm_page_t * pages,int off,int len,caddr_t cp)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
m_epg_pages_extent(struct mbuf * m,int idx,u_int pglen)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 *
m_epg_segment(struct mbuf * m,size_t offset,size_t * len)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 *
m_epg_contiguous_subsegment(struct mbuf * m,size_t skip,size_t len)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
crypto_cursor_init(struct crypto_buffer_cursor * cc,const struct crypto_buffer * cb)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
crypto_cursor_advance(struct crypto_buffer_cursor * cc,size_t amount)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 *
crypto_cursor_segment(struct crypto_buffer_cursor * cc,size_t * len)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 *
crypto_cursor_segbase(struct crypto_buffer_cursor * cc)453 crypto_cursor_segbase(struct crypto_buffer_cursor *cc)
454 {
455 	size_t len;
456 
457 	return (crypto_cursor_segment(cc, &len));
458 }
459 
460 size_t
crypto_cursor_seglen(struct crypto_buffer_cursor * cc)461 crypto_cursor_seglen(struct crypto_buffer_cursor *cc)
462 {
463 	size_t len;
464 
465 	crypto_cursor_segment(cc, &len);
466 	return (len);
467 }
468 
469 void
crypto_cursor_copyback(struct crypto_buffer_cursor * cc,int size,const void * vsrc)470 crypto_cursor_copyback(struct crypto_buffer_cursor *cc, int size,
471     const void *vsrc)
472 {
473 	size_t remain, todo;
474 	const char *src;
475 	char *dst;
476 
477 	src = vsrc;
478 	switch (cc->cc_type) {
479 	case CRYPTO_BUF_CONTIG:
480 		MPASS(cc->cc_buf_len >= size);
481 		memcpy(cc->cc_buf, src, size);
482 		cc->cc_buf += size;
483 		cc->cc_buf_len -= size;
484 		break;
485 	case CRYPTO_BUF_MBUF:
486 		for (;;) {
487 			/*
488 			 * This uses m_copyback() for individual
489 			 * mbufs so that cc_mbuf and cc_offset are
490 			 * updated.
491 			 */
492 			remain = cc->cc_mbuf->m_len - cc->cc_offset;
493 			todo = MIN(remain, size);
494 			m_copyback(cc->cc_mbuf, cc->cc_offset, todo, src);
495 			src += todo;
496 			if (todo < remain) {
497 				cc->cc_offset += todo;
498 				break;
499 			}
500 			size -= todo;
501 			cc->cc_mbuf = cc->cc_mbuf->m_next;
502 			cc->cc_offset = 0;
503 			if (size == 0)
504 				break;
505 		}
506 		break;
507 	case CRYPTO_BUF_SINGLE_MBUF:
508 		MPASS(cc->cc_mbuf->m_len >= cc->cc_offset + size);
509 		m_copyback(cc->cc_mbuf, cc->cc_offset, size, src);
510 		cc->cc_offset += size;
511 		break;
512 	case CRYPTO_BUF_VMPAGE:
513 		for (;;) {
514 			dst = (char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(
515 			    *cc->cc_vmpage)) + cc->cc_offset;
516 			remain = MIN(PAGE_SIZE - cc->cc_offset, cc->cc_buf_len);
517 			todo = MIN(remain, size);
518 			memcpy(dst, src, todo);
519 			src += todo;
520 			cc->cc_buf_len -= todo;
521 			if (todo < remain) {
522 				cc->cc_offset += todo;
523 				break;
524 			}
525 			size -= todo;
526 			cc->cc_vmpage++;
527 			cc->cc_offset = 0;
528 			if (size == 0)
529 				break;
530 		}
531 		break;
532 	case CRYPTO_BUF_UIO:
533 		for (;;) {
534 			dst = (char *)cc->cc_iov->iov_base + cc->cc_offset;
535 			remain = cc->cc_iov->iov_len - cc->cc_offset;
536 			todo = MIN(remain, size);
537 			memcpy(dst, src, todo);
538 			src += todo;
539 			cc->cc_buf_len -= todo;
540 			if (todo < remain) {
541 				cc->cc_offset += todo;
542 				break;
543 			}
544 			size -= todo;
545 			cc->cc_iov++;
546 			cc->cc_offset = 0;
547 			if (size == 0)
548 				break;
549 		}
550 		break;
551 	default:
552 #ifdef INVARIANTS
553 		panic("%s: invalid buffer type %d", __func__, cc->cc_type);
554 #endif
555 		break;
556 	}
557 }
558 
559 void
crypto_cursor_copydata(struct crypto_buffer_cursor * cc,int size,void * vdst)560 crypto_cursor_copydata(struct crypto_buffer_cursor *cc, int size, void *vdst)
561 {
562 	size_t remain, todo;
563 	const char *src;
564 	char *dst;
565 
566 	dst = vdst;
567 	switch (cc->cc_type) {
568 	case CRYPTO_BUF_CONTIG:
569 		MPASS(cc->cc_buf_len >= size);
570 		memcpy(dst, cc->cc_buf, size);
571 		cc->cc_buf += size;
572 		cc->cc_buf_len -= size;
573 		break;
574 	case CRYPTO_BUF_MBUF:
575 		for (;;) {
576 			/*
577 			 * This uses m_copydata() for individual
578 			 * mbufs so that cc_mbuf and cc_offset are
579 			 * updated.
580 			 */
581 			remain = cc->cc_mbuf->m_len - cc->cc_offset;
582 			todo = MIN(remain, size);
583 			m_copydata(cc->cc_mbuf, cc->cc_offset, todo, dst);
584 			dst += todo;
585 			if (todo < remain) {
586 				cc->cc_offset += todo;
587 				break;
588 			}
589 			size -= todo;
590 			cc->cc_mbuf = cc->cc_mbuf->m_next;
591 			cc->cc_offset = 0;
592 			if (size == 0)
593 				break;
594 		}
595 		break;
596 	case CRYPTO_BUF_SINGLE_MBUF:
597 		MPASS(cc->cc_mbuf->m_len >= cc->cc_offset + size);
598 		m_copydata(cc->cc_mbuf, cc->cc_offset, size, dst);
599 		cc->cc_offset += size;
600 		break;
601 	case CRYPTO_BUF_VMPAGE:
602 		for (;;) {
603 			src = (char *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(
604 			    *cc->cc_vmpage)) + cc->cc_offset;
605 			remain = MIN(PAGE_SIZE - cc->cc_offset, cc->cc_buf_len);
606 			todo = MIN(remain, size);
607 			memcpy(dst, src, todo);
608 			dst += todo;
609 			cc->cc_buf_len -= todo;
610 			if (todo < remain) {
611 				cc->cc_offset += todo;
612 				break;
613 			}
614 			size -= todo;
615 			cc->cc_vmpage++;
616 			cc->cc_offset = 0;
617 			if (size == 0)
618 				break;
619 		}
620 		break;
621 	case CRYPTO_BUF_UIO:
622 		for (;;) {
623 			src = (const char *)cc->cc_iov->iov_base +
624 			    cc->cc_offset;
625 			remain = cc->cc_iov->iov_len - cc->cc_offset;
626 			todo = MIN(remain, size);
627 			memcpy(dst, src, todo);
628 			dst += todo;
629 			cc->cc_buf_len -= todo;
630 			if (todo < remain) {
631 				cc->cc_offset += todo;
632 				break;
633 			}
634 			size -= todo;
635 			cc->cc_iov++;
636 			cc->cc_offset = 0;
637 			if (size == 0)
638 				break;
639 		}
640 		break;
641 	default:
642 #ifdef INVARIANTS
643 		panic("%s: invalid buffer type %d", __func__, cc->cc_type);
644 #endif
645 		break;
646 	}
647 }
648 
649 /*
650  * To avoid advancing 'cursor', make a local copy that gets advanced
651  * instead.
652  */
653 void
crypto_cursor_copydata_noadv(struct crypto_buffer_cursor * cc,int size,void * vdst)654 crypto_cursor_copydata_noadv(struct crypto_buffer_cursor *cc, int size,
655     void *vdst)
656 {
657 	struct crypto_buffer_cursor copy;
658 
659 	copy = *cc;
660 	crypto_cursor_copydata(&copy, size, vdst);
661 }
662 
663 /*
664  * Apply function f to the data in an iovec list starting "off" bytes from
665  * the beginning, continuing for "len" bytes.
666  */
667 static int
cuio_apply(struct uio * uio,int off,int len,int (* f)(void *,const void *,u_int),void * arg)668 cuio_apply(struct uio *uio, int off, int len,
669     int (*f)(void *, const void *, u_int), void *arg)
670 {
671 	struct iovec *iov = uio->uio_iov;
672 	int iol __diagused = uio->uio_iovcnt;
673 	unsigned count;
674 	int rval;
675 
676 	CUIO_SKIP();
677 	while (len > 0) {
678 		KASSERT(iol >= 0, ("%s: empty", __func__));
679 		count = min(iov->iov_len - off, len);
680 		rval = (*f)(arg, ((caddr_t)iov->iov_base) + off, count);
681 		if (rval)
682 			return (rval);
683 		len -= count;
684 		off = 0;
685 		iol--;
686 		iov++;
687 	}
688 	return (0);
689 }
690 
691 void
crypto_copyback(struct cryptop * crp,int off,int size,const void * src)692 crypto_copyback(struct cryptop *crp, int off, int size, const void *src)
693 {
694 	struct crypto_buffer *cb;
695 
696 	if (crp->crp_obuf.cb_type != CRYPTO_BUF_NONE)
697 		cb = &crp->crp_obuf;
698 	else
699 		cb = &crp->crp_buf;
700 	switch (cb->cb_type) {
701 	case CRYPTO_BUF_MBUF:
702 	case CRYPTO_BUF_SINGLE_MBUF:
703 		m_copyback(cb->cb_mbuf, off, size, src);
704 		break;
705 #if CRYPTO_MAY_HAVE_VMPAGE
706 	case CRYPTO_BUF_VMPAGE:
707 		MPASS(size <= cb->cb_vm_page_len);
708 		MPASS(size + off <=
709 		    cb->cb_vm_page_len + cb->cb_vm_page_offset);
710 		cvm_page_copyback(cb->cb_vm_page,
711 		    off + cb->cb_vm_page_offset, size, src);
712 		break;
713 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
714 	case CRYPTO_BUF_UIO:
715 		cuio_copyback(cb->cb_uio, off, size, src);
716 		break;
717 	case CRYPTO_BUF_CONTIG:
718 		MPASS(off + size <= cb->cb_buf_len);
719 		bcopy(src, cb->cb_buf + off, size);
720 		break;
721 	default:
722 #ifdef INVARIANTS
723 		panic("invalid crp buf type %d", cb->cb_type);
724 #endif
725 		break;
726 	}
727 }
728 
729 void
crypto_copydata(struct cryptop * crp,int off,int size,void * dst)730 crypto_copydata(struct cryptop *crp, int off, int size, void *dst)
731 {
732 
733 	switch (crp->crp_buf.cb_type) {
734 	case CRYPTO_BUF_MBUF:
735 	case CRYPTO_BUF_SINGLE_MBUF:
736 		m_copydata(crp->crp_buf.cb_mbuf, off, size, dst);
737 		break;
738 #if CRYPTO_MAY_HAVE_VMPAGE
739 	case CRYPTO_BUF_VMPAGE:
740 		MPASS(size <= crp->crp_buf.cb_vm_page_len);
741 		MPASS(size + off <= crp->crp_buf.cb_vm_page_len +
742 		    crp->crp_buf.cb_vm_page_offset);
743 		cvm_page_copydata(crp->crp_buf.cb_vm_page,
744 		    off + crp->crp_buf.cb_vm_page_offset, size, dst);
745 		break;
746 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
747 	case CRYPTO_BUF_UIO:
748 		cuio_copydata(crp->crp_buf.cb_uio, off, size, dst);
749 		break;
750 	case CRYPTO_BUF_CONTIG:
751 		MPASS(off + size <= crp->crp_buf.cb_buf_len);
752 		bcopy(crp->crp_buf.cb_buf + off, dst, size);
753 		break;
754 	default:
755 #ifdef INVARIANTS
756 		panic("invalid crp buf type %d", crp->crp_buf.cb_type);
757 #endif
758 		break;
759 	}
760 }
761 
762 int
crypto_apply_buf(struct crypto_buffer * cb,int off,int len,int (* f)(void *,const void *,u_int),void * arg)763 crypto_apply_buf(struct crypto_buffer *cb, int off, int len,
764     int (*f)(void *, const void *, u_int), void *arg)
765 {
766 	int error;
767 
768 	switch (cb->cb_type) {
769 	case CRYPTO_BUF_MBUF:
770 	case CRYPTO_BUF_SINGLE_MBUF:
771 		error = m_apply(cb->cb_mbuf, off, len,
772 		    (int (*)(void *, void *, u_int))f, arg);
773 		break;
774 	case CRYPTO_BUF_UIO:
775 		error = cuio_apply(cb->cb_uio, off, len, f, arg);
776 		break;
777 #if CRYPTO_MAY_HAVE_VMPAGE
778 	case CRYPTO_BUF_VMPAGE:
779 		error = cvm_page_apply(cb->cb_vm_page,
780 		    off + cb->cb_vm_page_offset, len, f, arg);
781 		break;
782 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
783 	case CRYPTO_BUF_CONTIG:
784 		MPASS(off + len <= cb->cb_buf_len);
785 		error = (*f)(arg, cb->cb_buf + off, len);
786 		break;
787 	default:
788 #ifdef INVARIANTS
789 		panic("invalid crypto buf type %d", cb->cb_type);
790 #endif
791 		error = 0;
792 		break;
793 	}
794 	return (error);
795 }
796 
797 int
crypto_apply(struct cryptop * crp,int off,int len,int (* f)(void *,const void *,u_int),void * arg)798 crypto_apply(struct cryptop *crp, int off, int len,
799     int (*f)(void *, const void *, u_int), void *arg)
800 {
801 	return (crypto_apply_buf(&crp->crp_buf, off, len, f, arg));
802 }
803 
804 static inline void *
m_contiguous_subsegment(struct mbuf * m,size_t skip,size_t len)805 m_contiguous_subsegment(struct mbuf *m, size_t skip, size_t len)
806 {
807 	int rel_off;
808 
809 	MPASS(skip <= INT_MAX);
810 
811 	m = m_getptr(m, (int)skip, &rel_off);
812 	if (m == NULL)
813 		return (NULL);
814 
815 	MPASS(rel_off >= 0);
816 	skip = rel_off;
817 	if (skip + len > m->m_len)
818 		return (NULL);
819 
820 	if (m->m_flags & M_EXTPG)
821 		return (m_epg_contiguous_subsegment(m, skip, len));
822 	return (mtod(m, char*) + skip);
823 }
824 
825 static inline void *
cuio_contiguous_segment(struct uio * uio,size_t skip,size_t len)826 cuio_contiguous_segment(struct uio *uio, size_t skip, size_t len)
827 {
828 	int rel_off, idx;
829 
830 	MPASS(skip <= INT_MAX);
831 	idx = cuio_getptr(uio, (int)skip, &rel_off);
832 	if (idx < 0)
833 		return (NULL);
834 
835 	MPASS(rel_off >= 0);
836 	skip = rel_off;
837 	if (skip + len > uio->uio_iov[idx].iov_len)
838 		return (NULL);
839 	return ((char *)uio->uio_iov[idx].iov_base + skip);
840 }
841 
842 void *
crypto_buffer_contiguous_subsegment(struct crypto_buffer * cb,size_t skip,size_t len)843 crypto_buffer_contiguous_subsegment(struct crypto_buffer *cb, size_t skip,
844     size_t len)
845 {
846 
847 	switch (cb->cb_type) {
848 	case CRYPTO_BUF_MBUF:
849 	case CRYPTO_BUF_SINGLE_MBUF:
850 		return (m_contiguous_subsegment(cb->cb_mbuf, skip, len));
851 	case CRYPTO_BUF_UIO:
852 		return (cuio_contiguous_segment(cb->cb_uio, skip, len));
853 #if CRYPTO_MAY_HAVE_VMPAGE
854 	case CRYPTO_BUF_VMPAGE:
855 		MPASS(skip + len <= cb->cb_vm_page_len);
856 		return (cvm_page_contiguous_segment(cb->cb_vm_page,
857 		    skip + cb->cb_vm_page_offset, len));
858 #endif /* CRYPTO_MAY_HAVE_VMPAGE */
859 	case CRYPTO_BUF_CONTIG:
860 		MPASS(skip + len <= cb->cb_buf_len);
861 		return (cb->cb_buf + skip);
862 	default:
863 #ifdef INVARIANTS
864 		panic("invalid crp buf type %d", cb->cb_type);
865 #endif
866 		return (NULL);
867 	}
868 }
869 
870 void *
crypto_contiguous_subsegment(struct cryptop * crp,size_t skip,size_t len)871 crypto_contiguous_subsegment(struct cryptop *crp, size_t skip, size_t len)
872 {
873 	return (crypto_buffer_contiguous_subsegment(&crp->crp_buf, skip, len));
874 }
875