xref: /freebsd/sys/opencrypto/ktls_ocf.c (revision a466cc55373fc3cf86837f09da729535b57e69a1)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2019 Netflix Inc.
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  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/counter.h>
34 #include <sys/endian.h>
35 #include <sys/kernel.h>
36 #include <sys/ktls.h>
37 #include <sys/lock.h>
38 #include <sys/malloc.h>
39 #include <sys/mbuf.h>
40 #include <sys/module.h>
41 #include <sys/mutex.h>
42 #include <sys/sysctl.h>
43 #include <sys/uio.h>
44 #include <vm/vm.h>
45 #include <vm/pmap.h>
46 #include <vm/vm_param.h>
47 #include <netinet/in.h>
48 #include <opencrypto/cryptodev.h>
49 #include <opencrypto/ktls.h>
50 
51 struct ktls_ocf_sw {
52 	/* Encrypt a single outbound TLS record. */
53 	int	(*encrypt)(struct ktls_ocf_encrypt_state *state,
54 	    struct ktls_session *tls, struct mbuf *m,
55 	    struct iovec *outiov, int outiovcnt);
56 
57 	/* Re-encrypt a received TLS record that is partially decrypted. */
58 	int	(*recrypt)(struct ktls_session *tls,
59 	    const struct tls_record_layer *hdr, struct mbuf *m,
60 	    uint64_t seqno);
61 
62 	/* Decrypt a received TLS record. */
63 	int	(*decrypt)(struct ktls_session *tls,
64 	    const struct tls_record_layer *hdr, struct mbuf *m,
65 	    uint64_t seqno, int *trailer_len);
66 };
67 
68 struct ktls_ocf_session {
69 	const struct ktls_ocf_sw *sw;
70 	crypto_session_t sid;
71 	crypto_session_t mac_sid;
72 	crypto_session_t recrypt_sid;
73 	struct mtx lock;
74 	int mac_len;
75 	bool implicit_iv;
76 
77 	/* Only used for TLS 1.0 with the implicit IV. */
78 #ifdef INVARIANTS
79 	bool in_progress;
80 	uint64_t next_seqno;
81 #endif
82 	char iv[AES_BLOCK_LEN];
83 };
84 
85 struct ocf_operation {
86 	struct ktls_ocf_session *os;
87 	bool done;
88 };
89 
90 static MALLOC_DEFINE(M_KTLS_OCF, "ktls_ocf", "OCF KTLS");
91 
92 SYSCTL_DECL(_kern_ipc_tls);
93 SYSCTL_DECL(_kern_ipc_tls_stats);
94 
95 static SYSCTL_NODE(_kern_ipc_tls_stats, OID_AUTO, ocf,
96     CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
97     "Kernel TLS offload via OCF stats");
98 
99 static COUNTER_U64_DEFINE_EARLY(ocf_tls10_cbc_encrypts);
100 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls10_cbc_encrypts,
101     CTLFLAG_RD, &ocf_tls10_cbc_encrypts,
102     "Total number of OCF TLS 1.0 CBC encryption operations");
103 
104 static COUNTER_U64_DEFINE_EARLY(ocf_tls11_cbc_decrypts);
105 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls11_cbc_decrypts,
106     CTLFLAG_RD, &ocf_tls11_cbc_decrypts,
107     "Total number of OCF TLS 1.1/1.2 CBC decryption operations");
108 
109 static COUNTER_U64_DEFINE_EARLY(ocf_tls11_cbc_encrypts);
110 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls11_cbc_encrypts,
111     CTLFLAG_RD, &ocf_tls11_cbc_encrypts,
112     "Total number of OCF TLS 1.1/1.2 CBC encryption operations");
113 
114 static COUNTER_U64_DEFINE_EARLY(ocf_tls12_gcm_decrypts);
115 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls12_gcm_decrypts,
116     CTLFLAG_RD, &ocf_tls12_gcm_decrypts,
117     "Total number of OCF TLS 1.2 GCM decryption operations");
118 
119 static COUNTER_U64_DEFINE_EARLY(ocf_tls12_gcm_encrypts);
120 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls12_gcm_encrypts,
121     CTLFLAG_RD, &ocf_tls12_gcm_encrypts,
122     "Total number of OCF TLS 1.2 GCM encryption operations");
123 
124 static COUNTER_U64_DEFINE_EARLY(ocf_tls12_gcm_recrypts);
125 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls12_gcm_recrypts,
126     CTLFLAG_RD, &ocf_tls12_gcm_recrypts,
127     "Total number of OCF TLS 1.2 GCM re-encryption operations");
128 
129 static COUNTER_U64_DEFINE_EARLY(ocf_tls12_chacha20_decrypts);
130 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls12_chacha20_decrypts,
131     CTLFLAG_RD, &ocf_tls12_chacha20_decrypts,
132     "Total number of OCF TLS 1.2 Chacha20-Poly1305 decryption operations");
133 
134 static COUNTER_U64_DEFINE_EARLY(ocf_tls12_chacha20_encrypts);
135 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls12_chacha20_encrypts,
136     CTLFLAG_RD, &ocf_tls12_chacha20_encrypts,
137     "Total number of OCF TLS 1.2 Chacha20-Poly1305 encryption operations");
138 
139 static COUNTER_U64_DEFINE_EARLY(ocf_tls13_gcm_decrypts);
140 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls13_gcm_decrypts,
141     CTLFLAG_RD, &ocf_tls13_gcm_decrypts,
142     "Total number of OCF TLS 1.3 GCM decryption operations");
143 
144 static COUNTER_U64_DEFINE_EARLY(ocf_tls13_gcm_encrypts);
145 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls13_gcm_encrypts,
146     CTLFLAG_RD, &ocf_tls13_gcm_encrypts,
147     "Total number of OCF TLS 1.3 GCM encryption operations");
148 
149 static COUNTER_U64_DEFINE_EARLY(ocf_tls13_gcm_recrypts);
150 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls13_gcm_recrypts,
151     CTLFLAG_RD, &ocf_tls13_gcm_recrypts,
152     "Total number of OCF TLS 1.3 GCM re-encryption operations");
153 
154 static COUNTER_U64_DEFINE_EARLY(ocf_tls13_chacha20_decrypts);
155 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls13_chacha20_decrypts,
156     CTLFLAG_RD, &ocf_tls13_chacha20_decrypts,
157     "Total number of OCF TLS 1.3 Chacha20-Poly1305 decryption operations");
158 
159 static COUNTER_U64_DEFINE_EARLY(ocf_tls13_chacha20_encrypts);
160 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls13_chacha20_encrypts,
161     CTLFLAG_RD, &ocf_tls13_chacha20_encrypts,
162     "Total number of OCF TLS 1.3 Chacha20-Poly1305 encryption operations");
163 
164 static COUNTER_U64_DEFINE_EARLY(ocf_inplace);
165 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, inplace,
166     CTLFLAG_RD, &ocf_inplace,
167     "Total number of OCF in-place operations");
168 
169 static COUNTER_U64_DEFINE_EARLY(ocf_separate_output);
170 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, separate_output,
171     CTLFLAG_RD, &ocf_separate_output,
172     "Total number of OCF operations with a separate output buffer");
173 
174 static COUNTER_U64_DEFINE_EARLY(ocf_retries);
175 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, retries, CTLFLAG_RD,
176     &ocf_retries,
177     "Number of OCF encryption operation retries");
178 
179 static int
180 ktls_ocf_callback_sync(struct cryptop *crp __unused)
181 {
182 	return (0);
183 }
184 
185 static int
186 ktls_ocf_callback_async(struct cryptop *crp)
187 {
188 	struct ocf_operation *oo;
189 
190 	oo = crp->crp_opaque;
191 	mtx_lock(&oo->os->lock);
192 	oo->done = true;
193 	mtx_unlock(&oo->os->lock);
194 	wakeup(oo);
195 	return (0);
196 }
197 
198 static int
199 ktls_ocf_dispatch(struct ktls_ocf_session *os, struct cryptop *crp)
200 {
201 	struct ocf_operation oo;
202 	int error;
203 	bool async;
204 
205 	oo.os = os;
206 	oo.done = false;
207 
208 	crp->crp_opaque = &oo;
209 	for (;;) {
210 		async = !CRYPTO_SESS_SYNC(crp->crp_session);
211 		crp->crp_callback = async ? ktls_ocf_callback_async :
212 		    ktls_ocf_callback_sync;
213 
214 		error = crypto_dispatch(crp);
215 		if (error)
216 			break;
217 		if (async) {
218 			mtx_lock(&os->lock);
219 			while (!oo.done)
220 				mtx_sleep(&oo, &os->lock, 0, "ocfktls", 0);
221 			mtx_unlock(&os->lock);
222 		}
223 
224 		if (crp->crp_etype != EAGAIN) {
225 			error = crp->crp_etype;
226 			break;
227 		}
228 
229 		crp->crp_etype = 0;
230 		crp->crp_flags &= ~CRYPTO_F_DONE;
231 		oo.done = false;
232 		counter_u64_add(ocf_retries, 1);
233 	}
234 	return (error);
235 }
236 
237 static int
238 ktls_ocf_dispatch_async_cb(struct cryptop *crp)
239 {
240 	struct ktls_ocf_encrypt_state *state;
241 	int error;
242 
243 	state = crp->crp_opaque;
244 	if (crp->crp_etype == EAGAIN) {
245 		crp->crp_etype = 0;
246 		crp->crp_flags &= ~CRYPTO_F_DONE;
247 		counter_u64_add(ocf_retries, 1);
248 		error = crypto_dispatch(crp);
249 		if (error != 0) {
250 			crypto_destroyreq(crp);
251 			ktls_encrypt_cb(state, error);
252 		}
253 		return (0);
254 	}
255 
256 	error = crp->crp_etype;
257 	crypto_destroyreq(crp);
258 	ktls_encrypt_cb(state, error);
259 	return (0);
260 }
261 
262 static int
263 ktls_ocf_dispatch_async(struct ktls_ocf_encrypt_state *state,
264     struct cryptop *crp)
265 {
266 	int error;
267 
268 	crp->crp_opaque = state;
269 	crp->crp_callback = ktls_ocf_dispatch_async_cb;
270 	error = crypto_dispatch(crp);
271 	if (error != 0)
272 		crypto_destroyreq(crp);
273 	return (error);
274 }
275 
276 static int
277 ktls_ocf_tls_cbc_encrypt(struct ktls_ocf_encrypt_state *state,
278     struct ktls_session *tls, struct mbuf *m, struct iovec *outiov,
279     int outiovcnt)
280 {
281 	const struct tls_record_layer *hdr;
282 	struct uio *uio;
283 	struct tls_mac_data *ad;
284 	struct cryptop *crp;
285 	struct ktls_ocf_session *os;
286 	struct iovec iov[m->m_epg_npgs + 2];
287 	u_int pgoff;
288 	int i, error;
289 	uint16_t tls_comp_len;
290 	uint8_t pad;
291 
292 	MPASS(outiovcnt + 1 <= nitems(iov));
293 
294 	os = tls->ocf_session;
295 	hdr = (const struct tls_record_layer *)m->m_epg_hdr;
296 	crp = &state->crp;
297 	uio = &state->uio;
298 	MPASS(tls->sync_dispatch);
299 
300 #ifdef INVARIANTS
301 	if (os->implicit_iv) {
302 		mtx_lock(&os->lock);
303 		KASSERT(!os->in_progress,
304 		    ("concurrent implicit IV encryptions"));
305 		if (os->next_seqno != m->m_epg_seqno) {
306 			printf("KTLS CBC: TLS records out of order.  "
307 			    "Expected %ju, got %ju\n",
308 			    (uintmax_t)os->next_seqno,
309 			    (uintmax_t)m->m_epg_seqno);
310 			mtx_unlock(&os->lock);
311 			return (EINVAL);
312 		}
313 		os->in_progress = true;
314 		mtx_unlock(&os->lock);
315 	}
316 #endif
317 
318 	/* Payload length. */
319 	tls_comp_len = m->m_len - (m->m_epg_hdrlen + m->m_epg_trllen);
320 
321 	/* Initialize the AAD. */
322 	ad = &state->mac;
323 	ad->seq = htobe64(m->m_epg_seqno);
324 	ad->type = hdr->tls_type;
325 	ad->tls_vmajor = hdr->tls_vmajor;
326 	ad->tls_vminor = hdr->tls_vminor;
327 	ad->tls_length = htons(tls_comp_len);
328 
329 	/* First, compute the MAC. */
330 	iov[0].iov_base = ad;
331 	iov[0].iov_len = sizeof(*ad);
332 	pgoff = m->m_epg_1st_off;
333 	for (i = 0; i < m->m_epg_npgs; i++, pgoff = 0) {
334 		iov[i + 1].iov_base = (void *)PHYS_TO_DMAP(m->m_epg_pa[i] +
335 		    pgoff);
336 		iov[i + 1].iov_len = m_epg_pagelen(m, i, pgoff);
337 	}
338 	iov[m->m_epg_npgs + 1].iov_base = m->m_epg_trail;
339 	iov[m->m_epg_npgs + 1].iov_len = os->mac_len;
340 	uio->uio_iov = iov;
341 	uio->uio_iovcnt = m->m_epg_npgs + 2;
342 	uio->uio_offset = 0;
343 	uio->uio_segflg = UIO_SYSSPACE;
344 	uio->uio_td = curthread;
345 	uio->uio_resid = sizeof(*ad) + tls_comp_len + os->mac_len;
346 
347 	crypto_initreq(crp, os->mac_sid);
348 	crp->crp_payload_start = 0;
349 	crp->crp_payload_length = sizeof(*ad) + tls_comp_len;
350 	crp->crp_digest_start = crp->crp_payload_length;
351 	crp->crp_op = CRYPTO_OP_COMPUTE_DIGEST;
352 	crp->crp_flags = CRYPTO_F_CBIMM;
353 	crypto_use_uio(crp, uio);
354 	error = ktls_ocf_dispatch(os, crp);
355 
356 	crypto_destroyreq(crp);
357 	if (error) {
358 #ifdef INVARIANTS
359 		if (os->implicit_iv) {
360 			mtx_lock(&os->lock);
361 			os->in_progress = false;
362 			mtx_unlock(&os->lock);
363 		}
364 #endif
365 		return (error);
366 	}
367 
368 	/* Second, add the padding. */
369 	pad = m->m_epg_trllen - os->mac_len - 1;
370 	for (i = 0; i < pad + 1; i++)
371 		m->m_epg_trail[os->mac_len + i] = pad;
372 
373 	/* Finally, encrypt the record. */
374 	crypto_initreq(crp, os->sid);
375 	crp->crp_payload_start = m->m_epg_hdrlen;
376 	crp->crp_payload_length = tls_comp_len + m->m_epg_trllen;
377 	KASSERT(crp->crp_payload_length % AES_BLOCK_LEN == 0,
378 	    ("invalid encryption size"));
379 	crypto_use_single_mbuf(crp, m);
380 	crp->crp_op = CRYPTO_OP_ENCRYPT;
381 	crp->crp_flags = CRYPTO_F_CBIMM | CRYPTO_F_IV_SEPARATE;
382 	if (os->implicit_iv)
383 		memcpy(crp->crp_iv, os->iv, AES_BLOCK_LEN);
384 	else
385 		memcpy(crp->crp_iv, hdr + 1, AES_BLOCK_LEN);
386 
387 	if (outiov != NULL) {
388 		uio->uio_iov = outiov;
389 		uio->uio_iovcnt = outiovcnt;
390 		uio->uio_offset = 0;
391 		uio->uio_segflg = UIO_SYSSPACE;
392 		uio->uio_td = curthread;
393 		uio->uio_resid = crp->crp_payload_length;
394 		crypto_use_output_uio(crp, uio);
395 	}
396 
397 	if (os->implicit_iv)
398 		counter_u64_add(ocf_tls10_cbc_encrypts, 1);
399 	else
400 		counter_u64_add(ocf_tls11_cbc_encrypts, 1);
401 	if (outiov != NULL)
402 		counter_u64_add(ocf_separate_output, 1);
403 	else
404 		counter_u64_add(ocf_inplace, 1);
405 	error = ktls_ocf_dispatch(os, crp);
406 
407 	crypto_destroyreq(crp);
408 
409 	if (os->implicit_iv) {
410 		KASSERT(os->mac_len + pad + 1 >= AES_BLOCK_LEN,
411 		    ("trailer too short to read IV"));
412 		memcpy(os->iv, m->m_epg_trail + m->m_epg_trllen - AES_BLOCK_LEN,
413 		    AES_BLOCK_LEN);
414 #ifdef INVARIANTS
415 		mtx_lock(&os->lock);
416 		os->next_seqno = m->m_epg_seqno + 1;
417 		os->in_progress = false;
418 		mtx_unlock(&os->lock);
419 #endif
420 	}
421 	return (error);
422 }
423 
424 static int
425 check_padding(void *arg, void *data, u_int len)
426 {
427 	uint8_t pad = *(uint8_t *)arg;
428 	const char *cp = data;
429 
430 	while (len > 0) {
431 		if (*cp != pad)
432 			return (EBADMSG);
433 		cp++;
434 		len--;
435 	}
436 	return (0);
437 }
438 
439 static int
440 ktls_ocf_tls_cbc_decrypt(struct ktls_session *tls,
441     const struct tls_record_layer *hdr, struct mbuf *m, uint64_t seqno,
442     int *trailer_len)
443 {
444 	struct tls_mac_data ad;
445 	struct cryptop crp;
446 	struct uio uio;
447 	struct ktls_ocf_session *os;
448 	struct iovec *iov;
449 	struct mbuf *n;
450 	u_int iovcnt;
451 	int i, error, skip;
452 	uint16_t tls_len, tls_comp_len;
453 	uint8_t pad;
454 
455 	os = tls->ocf_session;
456 
457 	/*
458 	 * Ensure record is a multiple of the cipher block size and
459 	 * contains at least an explicit IV, MAC, and at least one
460 	 * padding byte.
461 	 */
462 	tls_len = ntohs(hdr->tls_length);
463 	if (tls_len % AES_BLOCK_LEN != 0 ||
464 	    tls_len < AES_BLOCK_LEN + roundup2(os->mac_len + 1, AES_BLOCK_LEN))
465 		return (EMSGSIZE);
466 
467 	/* First, decrypt the record. */
468 	crypto_initreq(&crp, os->sid);
469 	crp.crp_iv_start = sizeof(*hdr);
470 	crp.crp_payload_start = tls->params.tls_hlen;
471 	crp.crp_payload_length = tls_len - AES_BLOCK_LEN;
472 	crypto_use_mbuf(&crp, m);
473 	crp.crp_op = CRYPTO_OP_DECRYPT;
474 	crp.crp_flags = CRYPTO_F_CBIMM;
475 
476 	counter_u64_add(ocf_tls11_cbc_decrypts, 1);
477 
478 	error = ktls_ocf_dispatch(os, &crp);
479 	crypto_destroyreq(&crp);
480 	if (error)
481 		return (error);
482 
483 	/* Verify the padding. */
484 	m_copydata(m, sizeof(*hdr) + tls_len - 1, 1, &pad);
485 	*trailer_len = os->mac_len + pad + 1;
486 	if (AES_BLOCK_LEN + *trailer_len > tls_len)
487 		return (EBADMSG);
488 	error = m_apply(m, sizeof(*hdr) + tls_len - (pad + 1), pad + 1,
489 	    check_padding, &pad);
490 	if (error)
491 		return (error);
492 
493 	/* Verify the MAC. */
494 	tls_comp_len = tls_len - (AES_BLOCK_LEN + *trailer_len);
495 	memset(&uio, 0, sizeof(uio));
496 
497 	/*
498 	 * Allocate and populate the iov.  Have to skip over the TLS
499 	 * header in 'm' as it is not part of the MAC input.
500 	 */
501 	iovcnt = 1;
502 	for (n = m; n != NULL; n = n->m_next)
503 		iovcnt++;
504 	iov = malloc(iovcnt * sizeof(*iov), M_KTLS_OCF, M_WAITOK);
505 	iov[0].iov_base = &ad;
506 	iov[0].iov_len = sizeof(ad);
507 	skip = sizeof(*hdr) + AES_BLOCK_LEN;
508 	for (i = 1, n = m; n != NULL; i++, n = n->m_next) {
509 		if (n->m_len < skip) {
510 			skip -= n->m_len;
511 			continue;
512 		}
513 		iov[i].iov_base = mtod(n, char *) + skip;
514 		iov[i].iov_len = n->m_len - skip;
515 		skip = 0;
516 	}
517 	uio.uio_iov = iov;
518 	uio.uio_iovcnt = i;
519 	uio.uio_segflg = UIO_SYSSPACE;
520 	uio.uio_td = curthread;
521 	uio.uio_resid = sizeof(ad) + tls_len - AES_BLOCK_LEN;
522 
523 	/* Initialize the AAD. */
524 	ad.seq = htobe64(seqno);
525 	ad.type = hdr->tls_type;
526 	ad.tls_vmajor = hdr->tls_vmajor;
527 	ad.tls_vminor = hdr->tls_vminor;
528 	ad.tls_length = htons(tls_comp_len);
529 
530 	crypto_initreq(&crp, os->mac_sid);
531 	crp.crp_payload_start = 0;
532 	crp.crp_payload_length = sizeof(ad) + tls_comp_len;
533 	crp.crp_digest_start = crp.crp_payload_length;
534 	crp.crp_op = CRYPTO_OP_VERIFY_DIGEST;
535 	crp.crp_flags = CRYPTO_F_CBIMM;
536 	crypto_use_uio(&crp, &uio);
537 	error = ktls_ocf_dispatch(os, &crp);
538 
539 	crypto_destroyreq(&crp);
540 	free(iov, M_KTLS_OCF);
541 	return (error);
542 }
543 
544 static const struct ktls_ocf_sw ktls_ocf_tls_cbc_sw = {
545 	.encrypt = ktls_ocf_tls_cbc_encrypt,
546 	.decrypt = ktls_ocf_tls_cbc_decrypt
547 };
548 
549 static int
550 ktls_ocf_tls12_aead_encrypt(struct ktls_ocf_encrypt_state *state,
551     struct ktls_session *tls, struct mbuf *m, struct iovec *outiov,
552     int outiovcnt)
553 {
554 	const struct tls_record_layer *hdr;
555 	struct uio *uio;
556 	struct tls_aead_data *ad;
557 	struct cryptop *crp;
558 	struct ktls_ocf_session *os;
559 	int error;
560 	uint16_t tls_comp_len;
561 
562 	os = tls->ocf_session;
563 	hdr = (const struct tls_record_layer *)m->m_epg_hdr;
564 	crp = &state->crp;
565 	uio = &state->uio;
566 
567 	crypto_initreq(crp, os->sid);
568 
569 	/* Setup the IV. */
570 	if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16) {
571 		memcpy(crp->crp_iv, tls->params.iv, TLS_AEAD_GCM_LEN);
572 		memcpy(crp->crp_iv + TLS_AEAD_GCM_LEN, hdr + 1,
573 		    sizeof(uint64_t));
574 	} else {
575 		/*
576 		 * Chacha20-Poly1305 constructs the IV for TLS 1.2
577 		 * identically to constructing the IV for AEAD in TLS
578 		 * 1.3.
579 		 */
580 		memcpy(crp->crp_iv, tls->params.iv, tls->params.iv_len);
581 		*(uint64_t *)(crp->crp_iv + 4) ^= htobe64(m->m_epg_seqno);
582 	}
583 
584 	/* Setup the AAD. */
585 	ad = &state->aead;
586 	tls_comp_len = m->m_len - (m->m_epg_hdrlen + m->m_epg_trllen);
587 	ad->seq = htobe64(m->m_epg_seqno);
588 	ad->type = hdr->tls_type;
589 	ad->tls_vmajor = hdr->tls_vmajor;
590 	ad->tls_vminor = hdr->tls_vminor;
591 	ad->tls_length = htons(tls_comp_len);
592 	crp->crp_aad = ad;
593 	crp->crp_aad_length = sizeof(*ad);
594 
595 	/* Set fields for input payload. */
596 	crypto_use_single_mbuf(crp, m);
597 	crp->crp_payload_start = m->m_epg_hdrlen;
598 	crp->crp_payload_length = tls_comp_len;
599 
600 	if (outiov != NULL) {
601 		crp->crp_digest_start = crp->crp_payload_length;
602 
603 		uio->uio_iov = outiov;
604 		uio->uio_iovcnt = outiovcnt;
605 		uio->uio_offset = 0;
606 		uio->uio_segflg = UIO_SYSSPACE;
607 		uio->uio_td = curthread;
608 		uio->uio_resid = crp->crp_payload_length + tls->params.tls_tlen;
609 		crypto_use_output_uio(crp, uio);
610 	} else
611 		crp->crp_digest_start = crp->crp_payload_start +
612 		    crp->crp_payload_length;
613 
614 	crp->crp_op = CRYPTO_OP_ENCRYPT | CRYPTO_OP_COMPUTE_DIGEST;
615 	crp->crp_flags = CRYPTO_F_CBIMM | CRYPTO_F_IV_SEPARATE;
616 	if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16)
617 		counter_u64_add(ocf_tls12_gcm_encrypts, 1);
618 	else
619 		counter_u64_add(ocf_tls12_chacha20_encrypts, 1);
620 	if (outiov != NULL)
621 		counter_u64_add(ocf_separate_output, 1);
622 	else
623 		counter_u64_add(ocf_inplace, 1);
624 	if (tls->sync_dispatch) {
625 		error = ktls_ocf_dispatch(os, crp);
626 		crypto_destroyreq(crp);
627 	} else
628 		error = ktls_ocf_dispatch_async(state, crp);
629 	return (error);
630 }
631 
632 static int
633 ktls_ocf_tls12_aead_decrypt(struct ktls_session *tls,
634     const struct tls_record_layer *hdr, struct mbuf *m, uint64_t seqno,
635     int *trailer_len)
636 {
637 	struct tls_aead_data ad;
638 	struct cryptop crp;
639 	struct ktls_ocf_session *os;
640 	int error;
641 	uint16_t tls_comp_len, tls_len;
642 
643 	os = tls->ocf_session;
644 
645 	/* Ensure record contains at least an explicit IV and tag. */
646 	tls_len = ntohs(hdr->tls_length);
647 	if (tls_len + sizeof(*hdr) < tls->params.tls_hlen +
648 	    tls->params.tls_tlen)
649 		return (EMSGSIZE);
650 
651 	crypto_initreq(&crp, os->sid);
652 
653 	/* Setup the IV. */
654 	if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16) {
655 		memcpy(crp.crp_iv, tls->params.iv, TLS_AEAD_GCM_LEN);
656 		memcpy(crp.crp_iv + TLS_AEAD_GCM_LEN, hdr + 1,
657 		    sizeof(uint64_t));
658 	} else {
659 		/*
660 		 * Chacha20-Poly1305 constructs the IV for TLS 1.2
661 		 * identically to constructing the IV for AEAD in TLS
662 		 * 1.3.
663 		 */
664 		memcpy(crp.crp_iv, tls->params.iv, tls->params.iv_len);
665 		*(uint64_t *)(crp.crp_iv + 4) ^= htobe64(seqno);
666 	}
667 
668 	/* Setup the AAD. */
669 	if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16)
670 		tls_comp_len = tls_len -
671 		    (AES_GMAC_HASH_LEN + sizeof(uint64_t));
672 	else
673 		tls_comp_len = tls_len - POLY1305_HASH_LEN;
674 	ad.seq = htobe64(seqno);
675 	ad.type = hdr->tls_type;
676 	ad.tls_vmajor = hdr->tls_vmajor;
677 	ad.tls_vminor = hdr->tls_vminor;
678 	ad.tls_length = htons(tls_comp_len);
679 	crp.crp_aad = &ad;
680 	crp.crp_aad_length = sizeof(ad);
681 
682 	crp.crp_payload_start = tls->params.tls_hlen;
683 	crp.crp_payload_length = tls_comp_len;
684 	crp.crp_digest_start = crp.crp_payload_start + crp.crp_payload_length;
685 
686 	crp.crp_op = CRYPTO_OP_DECRYPT | CRYPTO_OP_VERIFY_DIGEST;
687 	crp.crp_flags = CRYPTO_F_CBIMM | CRYPTO_F_IV_SEPARATE;
688 	crypto_use_mbuf(&crp, m);
689 
690 	if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16)
691 		counter_u64_add(ocf_tls12_gcm_decrypts, 1);
692 	else
693 		counter_u64_add(ocf_tls12_chacha20_decrypts, 1);
694 	error = ktls_ocf_dispatch(os, &crp);
695 
696 	crypto_destroyreq(&crp);
697 	*trailer_len = tls->params.tls_tlen;
698 	return (error);
699 }
700 
701 /*
702  * Reconstruct encrypted mbuf data in input buffer.
703  */
704 static void
705 ktls_ocf_recrypt_fixup(struct mbuf *m, u_int skip, u_int len, char *buf)
706 {
707 	const char *src = buf;
708 	u_int todo;
709 
710 	while (skip >= m->m_len) {
711 		skip -= m->m_len;
712 		m = m->m_next;
713 	}
714 
715 	while (len > 0) {
716 		todo = m->m_len - skip;
717 		if (todo > len)
718 			todo = len;
719 
720 		if (m->m_flags & M_DECRYPTED)
721 			memcpy(mtod(m, char *) + skip, src, todo);
722 		src += todo;
723 		len -= todo;
724 		skip = 0;
725 		m = m->m_next;
726 	}
727 }
728 
729 static int
730 ktls_ocf_tls12_aead_recrypt(struct ktls_session *tls,
731     const struct tls_record_layer *hdr, struct mbuf *m,
732     uint64_t seqno)
733 {
734 	struct cryptop crp;
735 	struct ktls_ocf_session *os;
736 	char *buf;
737 	u_int payload_len;
738 	int error;
739 	uint16_t tls_len;
740 
741 	os = tls->ocf_session;
742 
743 	/* Ensure record contains at least an explicit IV and tag. */
744 	tls_len = ntohs(hdr->tls_length);
745 	if (tls_len < sizeof(uint64_t) + AES_GMAC_HASH_LEN)
746 		return (EMSGSIZE);
747 
748 	crypto_initreq(&crp, os->recrypt_sid);
749 
750 	KASSERT(tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16,
751 	    ("%s: only AES-GCM is supported", __func__));
752 
753 	/* Setup the IV. */
754 	memcpy(crp.crp_iv, tls->params.iv, TLS_AEAD_GCM_LEN);
755 	memcpy(crp.crp_iv + TLS_AEAD_GCM_LEN, hdr + 1, sizeof(uint64_t));
756 	be32enc(crp.crp_iv + AES_GCM_IV_LEN, 2);
757 
758 	payload_len = tls_len - (AES_GMAC_HASH_LEN + sizeof(uint64_t));
759 	crp.crp_op = CRYPTO_OP_ENCRYPT;
760 	crp.crp_flags = CRYPTO_F_CBIMM | CRYPTO_F_IV_SEPARATE;
761 	crypto_use_mbuf(&crp, m);
762 	crp.crp_payload_start = tls->params.tls_hlen;
763 	crp.crp_payload_length = payload_len;
764 
765 	buf = malloc(payload_len, M_KTLS_OCF, M_WAITOK);
766 	crypto_use_output_buf(&crp, buf, payload_len);
767 
768 	counter_u64_add(ocf_tls12_gcm_recrypts, 1);
769 	error = ktls_ocf_dispatch(os, &crp);
770 
771 	crypto_destroyreq(&crp);
772 
773 	if (error == 0)
774 		ktls_ocf_recrypt_fixup(m, tls->params.tls_hlen, payload_len,
775 		    buf);
776 
777 	free(buf, M_KTLS_OCF);
778 	return (error);
779 }
780 
781 static const struct ktls_ocf_sw ktls_ocf_tls12_aead_sw = {
782 	.encrypt = ktls_ocf_tls12_aead_encrypt,
783 	.recrypt = ktls_ocf_tls12_aead_recrypt,
784 	.decrypt = ktls_ocf_tls12_aead_decrypt,
785 };
786 
787 static int
788 ktls_ocf_tls13_aead_encrypt(struct ktls_ocf_encrypt_state *state,
789     struct ktls_session *tls, struct mbuf *m, struct iovec *outiov,
790     int outiovcnt)
791 {
792 	const struct tls_record_layer *hdr;
793 	struct uio *uio;
794 	struct tls_aead_data_13 *ad;
795 	struct cryptop *crp;
796 	struct ktls_ocf_session *os;
797 	int error;
798 
799 	os = tls->ocf_session;
800 	hdr = (const struct tls_record_layer *)m->m_epg_hdr;
801 	crp = &state->crp;
802 	uio = &state->uio;
803 
804 	crypto_initreq(crp, os->sid);
805 
806 	/* Setup the nonce. */
807 	memcpy(crp->crp_iv, tls->params.iv, tls->params.iv_len);
808 	*(uint64_t *)(crp->crp_iv + 4) ^= htobe64(m->m_epg_seqno);
809 
810 	/* Setup the AAD. */
811 	ad = &state->aead13;
812 	ad->type = hdr->tls_type;
813 	ad->tls_vmajor = hdr->tls_vmajor;
814 	ad->tls_vminor = hdr->tls_vminor;
815 	ad->tls_length = hdr->tls_length;
816 	crp->crp_aad = ad;
817 	crp->crp_aad_length = sizeof(*ad);
818 
819 	/* Set fields for input payload. */
820 	crypto_use_single_mbuf(crp, m);
821 	crp->crp_payload_start = m->m_epg_hdrlen;
822 	crp->crp_payload_length = m->m_len -
823 	    (m->m_epg_hdrlen + m->m_epg_trllen);
824 
825 	/* Store the record type as the first byte of the trailer. */
826 	m->m_epg_trail[0] = m->m_epg_record_type;
827 	crp->crp_payload_length++;
828 
829 	if (outiov != NULL) {
830 		crp->crp_digest_start = crp->crp_payload_length;
831 
832 		uio->uio_iov = outiov;
833 		uio->uio_iovcnt = outiovcnt;
834 		uio->uio_offset = 0;
835 		uio->uio_segflg = UIO_SYSSPACE;
836 		uio->uio_td = curthread;
837 		uio->uio_resid = m->m_len - m->m_epg_hdrlen;
838 		crypto_use_output_uio(crp, uio);
839 	} else
840 		crp->crp_digest_start = crp->crp_payload_start +
841 		    crp->crp_payload_length;
842 
843 	crp->crp_op = CRYPTO_OP_ENCRYPT | CRYPTO_OP_COMPUTE_DIGEST;
844 	crp->crp_flags = CRYPTO_F_CBIMM | CRYPTO_F_IV_SEPARATE;
845 
846 	if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16)
847 		counter_u64_add(ocf_tls13_gcm_encrypts, 1);
848 	else
849 		counter_u64_add(ocf_tls13_chacha20_encrypts, 1);
850 	if (outiov != NULL)
851 		counter_u64_add(ocf_separate_output, 1);
852 	else
853 		counter_u64_add(ocf_inplace, 1);
854 	if (tls->sync_dispatch) {
855 		error = ktls_ocf_dispatch(os, crp);
856 		crypto_destroyreq(crp);
857 	} else
858 		error = ktls_ocf_dispatch_async(state, crp);
859 	return (error);
860 }
861 
862 static int
863 ktls_ocf_tls13_aead_decrypt(struct ktls_session *tls,
864     const struct tls_record_layer *hdr, struct mbuf *m, uint64_t seqno,
865     int *trailer_len)
866 {
867 	struct tls_aead_data_13 ad;
868 	struct cryptop crp;
869 	struct ktls_ocf_session *os;
870 	int error;
871 	u_int tag_len;
872 	uint16_t tls_len;
873 
874 	os = tls->ocf_session;
875 
876 	tag_len = tls->params.tls_tlen - 1;
877 
878 	/* Payload must contain at least one byte for the record type. */
879 	tls_len = ntohs(hdr->tls_length);
880 	if (tls_len < tag_len + 1)
881 		return (EMSGSIZE);
882 
883 	crypto_initreq(&crp, os->sid);
884 
885 	/* Setup the nonce. */
886 	memcpy(crp.crp_iv, tls->params.iv, tls->params.iv_len);
887 	*(uint64_t *)(crp.crp_iv + 4) ^= htobe64(seqno);
888 
889 	/* Setup the AAD. */
890 	ad.type = hdr->tls_type;
891 	ad.tls_vmajor = hdr->tls_vmajor;
892 	ad.tls_vminor = hdr->tls_vminor;
893 	ad.tls_length = hdr->tls_length;
894 	crp.crp_aad = &ad;
895 	crp.crp_aad_length = sizeof(ad);
896 
897 	crp.crp_payload_start = tls->params.tls_hlen;
898 	crp.crp_payload_length = tls_len - tag_len;
899 	crp.crp_digest_start = crp.crp_payload_start + crp.crp_payload_length;
900 
901 	crp.crp_op = CRYPTO_OP_DECRYPT | CRYPTO_OP_VERIFY_DIGEST;
902 	crp.crp_flags = CRYPTO_F_CBIMM | CRYPTO_F_IV_SEPARATE;
903 	crypto_use_mbuf(&crp, m);
904 
905 	if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16)
906 		counter_u64_add(ocf_tls13_gcm_decrypts, 1);
907 	else
908 		counter_u64_add(ocf_tls13_chacha20_decrypts, 1);
909 	error = ktls_ocf_dispatch(os, &crp);
910 
911 	crypto_destroyreq(&crp);
912 	*trailer_len = tag_len;
913 	return (error);
914 }
915 
916 static int
917 ktls_ocf_tls13_aead_recrypt(struct ktls_session *tls,
918     const struct tls_record_layer *hdr, struct mbuf *m,
919     uint64_t seqno)
920 {
921 	struct cryptop crp;
922 	struct ktls_ocf_session *os;
923 	char *buf;
924 	u_int payload_len;
925 	int error;
926 	uint16_t tls_len;
927 
928 	os = tls->ocf_session;
929 
930 	/* Payload must contain at least one byte for the record type. */
931 	tls_len = ntohs(hdr->tls_length);
932 	if (tls_len < AES_GMAC_HASH_LEN + 1)
933 		return (EMSGSIZE);
934 
935 	crypto_initreq(&crp, os->recrypt_sid);
936 
937 	KASSERT(tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16,
938 	    ("%s: only AES-GCM is supported", __func__));
939 
940 	/* Setup the IV. */
941 	memcpy(crp.crp_iv, tls->params.iv, tls->params.iv_len);
942 	*(uint64_t *)(crp.crp_iv + 4) ^= htobe64(seqno);
943 	be32enc(crp.crp_iv + 12, 2);
944 
945 	payload_len = tls_len - AES_GMAC_HASH_LEN;
946 	crp.crp_op = CRYPTO_OP_ENCRYPT;
947 	crp.crp_flags = CRYPTO_F_CBIMM | CRYPTO_F_IV_SEPARATE;
948 	crypto_use_mbuf(&crp, m);
949 	crp.crp_payload_start = tls->params.tls_hlen;
950 	crp.crp_payload_length = payload_len;
951 
952 	buf = malloc(payload_len, M_KTLS_OCF, M_WAITOK);
953 	crypto_use_output_buf(&crp, buf, payload_len);
954 
955 	counter_u64_add(ocf_tls13_gcm_recrypts, 1);
956 	error = ktls_ocf_dispatch(os, &crp);
957 
958 	crypto_destroyreq(&crp);
959 
960 	if (error == 0)
961 		ktls_ocf_recrypt_fixup(m, tls->params.tls_hlen, payload_len,
962 		    buf);
963 
964 	free(buf, M_KTLS_OCF);
965 	return (error);
966 }
967 
968 static const struct ktls_ocf_sw ktls_ocf_tls13_aead_sw = {
969 	.encrypt = ktls_ocf_tls13_aead_encrypt,
970 	.recrypt = ktls_ocf_tls13_aead_recrypt,
971 	.decrypt = ktls_ocf_tls13_aead_decrypt,
972 };
973 
974 void
975 ktls_ocf_free(struct ktls_session *tls)
976 {
977 	struct ktls_ocf_session *os;
978 
979 	os = tls->ocf_session;
980 	crypto_freesession(os->sid);
981 	crypto_freesession(os->mac_sid);
982 	crypto_freesession(os->recrypt_sid);
983 	mtx_destroy(&os->lock);
984 	zfree(os, M_KTLS_OCF);
985 }
986 
987 int
988 ktls_ocf_try(struct socket *so, struct ktls_session *tls, int direction)
989 {
990 	struct crypto_session_params csp, mac_csp, recrypt_csp;
991 	struct ktls_ocf_session *os;
992 	int error, mac_len;
993 
994 	memset(&csp, 0, sizeof(csp));
995 	memset(&mac_csp, 0, sizeof(mac_csp));
996 	mac_csp.csp_mode = CSP_MODE_NONE;
997 	mac_len = 0;
998 	memset(&recrypt_csp, 0, sizeof(mac_csp));
999 	recrypt_csp.csp_mode = CSP_MODE_NONE;
1000 
1001 	switch (tls->params.cipher_algorithm) {
1002 	case CRYPTO_AES_NIST_GCM_16:
1003 		switch (tls->params.cipher_key_len) {
1004 		case 128 / 8:
1005 		case 256 / 8:
1006 			break;
1007 		default:
1008 			return (EINVAL);
1009 		}
1010 
1011 		/* Only TLS 1.2 and 1.3 are supported. */
1012 		if (tls->params.tls_vmajor != TLS_MAJOR_VER_ONE ||
1013 		    tls->params.tls_vminor < TLS_MINOR_VER_TWO ||
1014 		    tls->params.tls_vminor > TLS_MINOR_VER_THREE)
1015 			return (EPROTONOSUPPORT);
1016 
1017 		csp.csp_flags |= CSP_F_SEPARATE_OUTPUT | CSP_F_SEPARATE_AAD;
1018 		csp.csp_mode = CSP_MODE_AEAD;
1019 		csp.csp_cipher_alg = CRYPTO_AES_NIST_GCM_16;
1020 		csp.csp_cipher_key = tls->params.cipher_key;
1021 		csp.csp_cipher_klen = tls->params.cipher_key_len;
1022 		csp.csp_ivlen = AES_GCM_IV_LEN;
1023 
1024 		recrypt_csp.csp_flags |= CSP_F_SEPARATE_OUTPUT;
1025 		recrypt_csp.csp_mode = CSP_MODE_CIPHER;
1026 		recrypt_csp.csp_cipher_alg = CRYPTO_AES_ICM;
1027 		recrypt_csp.csp_cipher_key = tls->params.cipher_key;
1028 		recrypt_csp.csp_cipher_klen = tls->params.cipher_key_len;
1029 		recrypt_csp.csp_ivlen = AES_BLOCK_LEN;
1030 		break;
1031 	case CRYPTO_AES_CBC:
1032 		switch (tls->params.cipher_key_len) {
1033 		case 128 / 8:
1034 		case 256 / 8:
1035 			break;
1036 		default:
1037 			return (EINVAL);
1038 		}
1039 
1040 		switch (tls->params.auth_algorithm) {
1041 		case CRYPTO_SHA1_HMAC:
1042 			mac_len = SHA1_HASH_LEN;
1043 			break;
1044 		case CRYPTO_SHA2_256_HMAC:
1045 			mac_len = SHA2_256_HASH_LEN;
1046 			break;
1047 		case CRYPTO_SHA2_384_HMAC:
1048 			mac_len = SHA2_384_HASH_LEN;
1049 			break;
1050 		default:
1051 			return (EINVAL);
1052 		}
1053 
1054 		/* Only TLS 1.0-1.2 are supported. */
1055 		if (tls->params.tls_vmajor != TLS_MAJOR_VER_ONE ||
1056 		    tls->params.tls_vminor < TLS_MINOR_VER_ZERO ||
1057 		    tls->params.tls_vminor > TLS_MINOR_VER_TWO)
1058 			return (EPROTONOSUPPORT);
1059 
1060 		/* AES-CBC is not supported for receive for TLS 1.0. */
1061 		if (direction == KTLS_RX &&
1062 		    tls->params.tls_vminor == TLS_MINOR_VER_ZERO)
1063 			return (EPROTONOSUPPORT);
1064 
1065 		csp.csp_flags |= CSP_F_SEPARATE_OUTPUT;
1066 		csp.csp_mode = CSP_MODE_CIPHER;
1067 		csp.csp_cipher_alg = CRYPTO_AES_CBC;
1068 		csp.csp_cipher_key = tls->params.cipher_key;
1069 		csp.csp_cipher_klen = tls->params.cipher_key_len;
1070 		csp.csp_ivlen = AES_BLOCK_LEN;
1071 
1072 		mac_csp.csp_flags |= CSP_F_SEPARATE_OUTPUT;
1073 		mac_csp.csp_mode = CSP_MODE_DIGEST;
1074 		mac_csp.csp_auth_alg = tls->params.auth_algorithm;
1075 		mac_csp.csp_auth_key = tls->params.auth_key;
1076 		mac_csp.csp_auth_klen = tls->params.auth_key_len;
1077 		break;
1078 	case CRYPTO_CHACHA20_POLY1305:
1079 		switch (tls->params.cipher_key_len) {
1080 		case 256 / 8:
1081 			break;
1082 		default:
1083 			return (EINVAL);
1084 		}
1085 
1086 		/* Only TLS 1.2 and 1.3 are supported. */
1087 		if (tls->params.tls_vmajor != TLS_MAJOR_VER_ONE ||
1088 		    tls->params.tls_vminor < TLS_MINOR_VER_TWO ||
1089 		    tls->params.tls_vminor > TLS_MINOR_VER_THREE)
1090 			return (EPROTONOSUPPORT);
1091 
1092 		csp.csp_flags |= CSP_F_SEPARATE_OUTPUT | CSP_F_SEPARATE_AAD;
1093 		csp.csp_mode = CSP_MODE_AEAD;
1094 		csp.csp_cipher_alg = CRYPTO_CHACHA20_POLY1305;
1095 		csp.csp_cipher_key = tls->params.cipher_key;
1096 		csp.csp_cipher_klen = tls->params.cipher_key_len;
1097 		csp.csp_ivlen = CHACHA20_POLY1305_IV_LEN;
1098 		break;
1099 	default:
1100 		return (EPROTONOSUPPORT);
1101 	}
1102 
1103 	os = malloc(sizeof(*os), M_KTLS_OCF, M_NOWAIT | M_ZERO);
1104 	if (os == NULL)
1105 		return (ENOMEM);
1106 
1107 	error = crypto_newsession(&os->sid, &csp,
1108 	    CRYPTO_FLAG_HARDWARE | CRYPTO_FLAG_SOFTWARE);
1109 	if (error) {
1110 		free(os, M_KTLS_OCF);
1111 		return (error);
1112 	}
1113 
1114 	if (mac_csp.csp_mode != CSP_MODE_NONE) {
1115 		error = crypto_newsession(&os->mac_sid, &mac_csp,
1116 		    CRYPTO_FLAG_HARDWARE | CRYPTO_FLAG_SOFTWARE);
1117 		if (error) {
1118 			crypto_freesession(os->sid);
1119 			free(os, M_KTLS_OCF);
1120 			return (error);
1121 		}
1122 		os->mac_len = mac_len;
1123 	}
1124 
1125 	if (recrypt_csp.csp_mode != CSP_MODE_NONE) {
1126 		error = crypto_newsession(&os->recrypt_sid, &recrypt_csp,
1127 		    CRYPTO_FLAG_HARDWARE | CRYPTO_FLAG_SOFTWARE);
1128 		if (error) {
1129 			crypto_freesession(os->sid);
1130 			free(os, M_KTLS_OCF);
1131 			return (error);
1132 		}
1133 	}
1134 
1135 	mtx_init(&os->lock, "ktls_ocf", NULL, MTX_DEF);
1136 	tls->ocf_session = os;
1137 	if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16 ||
1138 	    tls->params.cipher_algorithm == CRYPTO_CHACHA20_POLY1305) {
1139 		if (tls->params.tls_vminor == TLS_MINOR_VER_THREE)
1140 			os->sw = &ktls_ocf_tls13_aead_sw;
1141 		else
1142 			os->sw = &ktls_ocf_tls12_aead_sw;
1143 	} else {
1144 		os->sw = &ktls_ocf_tls_cbc_sw;
1145 		if (tls->params.tls_vminor == TLS_MINOR_VER_ZERO) {
1146 			os->implicit_iv = true;
1147 			memcpy(os->iv, tls->params.iv, AES_BLOCK_LEN);
1148 #ifdef INVARIANTS
1149 			os->next_seqno = tls->next_seqno;
1150 #endif
1151 		}
1152 	}
1153 
1154 	/*
1155 	 * AES-CBC is always synchronous currently.  Asynchronous
1156 	 * operation would require multiple callbacks and an additional
1157 	 * iovec array in ktls_ocf_encrypt_state.
1158 	 */
1159 	tls->sync_dispatch = CRYPTO_SESS_SYNC(os->sid) ||
1160 	    tls->params.cipher_algorithm == CRYPTO_AES_CBC;
1161 	return (0);
1162 }
1163 
1164 int
1165 ktls_ocf_encrypt(struct ktls_ocf_encrypt_state *state,
1166     struct ktls_session *tls, struct mbuf *m, struct iovec *outiov,
1167     int outiovcnt)
1168 {
1169 	return (tls->ocf_session->sw->encrypt(state, tls, m, outiov,
1170 	    outiovcnt));
1171 }
1172 
1173 int
1174 ktls_ocf_decrypt(struct ktls_session *tls, const struct tls_record_layer *hdr,
1175     struct mbuf *m, uint64_t seqno, int *trailer_len)
1176 {
1177 	return (tls->ocf_session->sw->decrypt(tls, hdr, m, seqno, trailer_len));
1178 }
1179 
1180 int
1181 ktls_ocf_recrypt(struct ktls_session *tls, const struct tls_record_layer *hdr,
1182     struct mbuf *m, uint64_t seqno)
1183 {
1184 	return (tls->ocf_session->sw->recrypt(tls, hdr, m, seqno));
1185 }
1186 
1187 bool
1188 ktls_ocf_recrypt_supported(struct ktls_session *tls)
1189 {
1190 	return (tls->ocf_session->sw->recrypt != NULL &&
1191 	    tls->ocf_session->recrypt_sid != NULL);
1192 }
1193