xref: /freebsd/sys/kern/uipc_ktls.c (revision 6419bb52)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2014-2019 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 "opt_inet.h"
32 #include "opt_inet6.h"
33 #include "opt_rss.h"
34 
35 #include <sys/param.h>
36 #include <sys/kernel.h>
37 #include <sys/ktls.h>
38 #include <sys/lock.h>
39 #include <sys/mbuf.h>
40 #include <sys/mutex.h>
41 #include <sys/rmlock.h>
42 #include <sys/proc.h>
43 #include <sys/protosw.h>
44 #include <sys/refcount.h>
45 #include <sys/smp.h>
46 #include <sys/socket.h>
47 #include <sys/socketvar.h>
48 #include <sys/sysctl.h>
49 #include <sys/taskqueue.h>
50 #include <sys/kthread.h>
51 #include <sys/uio.h>
52 #include <sys/vmmeter.h>
53 #if defined(__aarch64__) || defined(__amd64__) || defined(__i386__)
54 #include <machine/pcb.h>
55 #endif
56 #include <machine/vmparam.h>
57 #include <net/if.h>
58 #include <net/if_var.h>
59 #ifdef RSS
60 #include <net/netisr.h>
61 #include <net/rss_config.h>
62 #endif
63 #include <net/route.h>
64 #include <net/route/nhop.h>
65 #if defined(INET) || defined(INET6)
66 #include <netinet/in.h>
67 #include <netinet/in_pcb.h>
68 #endif
69 #include <netinet/tcp_var.h>
70 #ifdef TCP_OFFLOAD
71 #include <netinet/tcp_offload.h>
72 #endif
73 #include <opencrypto/xform.h>
74 #include <vm/uma_dbg.h>
75 #include <vm/vm.h>
76 #include <vm/vm_pageout.h>
77 #include <vm/vm_page.h>
78 
79 struct ktls_wq {
80 	struct mtx	mtx;
81 	STAILQ_HEAD(, mbuf) head;
82 	bool		running;
83 } __aligned(CACHE_LINE_SIZE);
84 
85 static struct ktls_wq *ktls_wq;
86 static struct proc *ktls_proc;
87 LIST_HEAD(, ktls_crypto_backend) ktls_backends;
88 static struct rmlock ktls_backends_lock;
89 static uma_zone_t ktls_session_zone;
90 static uint16_t ktls_cpuid_lookup[MAXCPU];
91 
92 SYSCTL_NODE(_kern_ipc, OID_AUTO, tls, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
93     "Kernel TLS offload");
94 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, stats, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
95     "Kernel TLS offload stats");
96 
97 static int ktls_allow_unload;
98 SYSCTL_INT(_kern_ipc_tls, OID_AUTO, allow_unload, CTLFLAG_RDTUN,
99     &ktls_allow_unload, 0, "Allow software crypto modules to unload");
100 
101 #ifdef RSS
102 static int ktls_bind_threads = 1;
103 #else
104 static int ktls_bind_threads;
105 #endif
106 SYSCTL_INT(_kern_ipc_tls, OID_AUTO, bind_threads, CTLFLAG_RDTUN,
107     &ktls_bind_threads, 0,
108     "Bind crypto threads to cores or domains at boot");
109 
110 static u_int ktls_maxlen = 16384;
111 SYSCTL_UINT(_kern_ipc_tls, OID_AUTO, maxlen, CTLFLAG_RWTUN,
112     &ktls_maxlen, 0, "Maximum TLS record size");
113 
114 static int ktls_number_threads;
115 SYSCTL_INT(_kern_ipc_tls_stats, OID_AUTO, threads, CTLFLAG_RD,
116     &ktls_number_threads, 0,
117     "Number of TLS threads in thread-pool");
118 
119 static bool ktls_offload_enable;
120 SYSCTL_BOOL(_kern_ipc_tls, OID_AUTO, enable, CTLFLAG_RW,
121     &ktls_offload_enable, 0,
122     "Enable support for kernel TLS offload");
123 
124 static bool ktls_cbc_enable = true;
125 SYSCTL_BOOL(_kern_ipc_tls, OID_AUTO, cbc_enable, CTLFLAG_RW,
126     &ktls_cbc_enable, 1,
127     "Enable Support of AES-CBC crypto for kernel TLS");
128 
129 static counter_u64_t ktls_tasks_active;
130 SYSCTL_COUNTER_U64(_kern_ipc_tls, OID_AUTO, tasks_active, CTLFLAG_RD,
131     &ktls_tasks_active, "Number of active tasks");
132 
133 static counter_u64_t ktls_cnt_on;
134 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, so_inqueue, CTLFLAG_RD,
135     &ktls_cnt_on, "Number of TLS records in queue to tasks for SW crypto");
136 
137 static counter_u64_t ktls_offload_total;
138 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, offload_total,
139     CTLFLAG_RD, &ktls_offload_total,
140     "Total successful TLS setups (parameters set)");
141 
142 static counter_u64_t ktls_offload_enable_calls;
143 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, enable_calls,
144     CTLFLAG_RD, &ktls_offload_enable_calls,
145     "Total number of TLS enable calls made");
146 
147 static counter_u64_t ktls_offload_active;
148 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, active, CTLFLAG_RD,
149     &ktls_offload_active, "Total Active TLS sessions");
150 
151 static counter_u64_t ktls_offload_failed_crypto;
152 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, failed_crypto, CTLFLAG_RD,
153     &ktls_offload_failed_crypto, "Total TLS crypto failures");
154 
155 static counter_u64_t ktls_switch_to_ifnet;
156 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_to_ifnet, CTLFLAG_RD,
157     &ktls_switch_to_ifnet, "TLS sessions switched from SW to ifnet");
158 
159 static counter_u64_t ktls_switch_to_sw;
160 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_to_sw, CTLFLAG_RD,
161     &ktls_switch_to_sw, "TLS sessions switched from ifnet to SW");
162 
163 static counter_u64_t ktls_switch_failed;
164 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_failed, CTLFLAG_RD,
165     &ktls_switch_failed, "TLS sessions unable to switch between SW and ifnet");
166 
167 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, sw, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
168     "Software TLS session stats");
169 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, ifnet, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
170     "Hardware (ifnet) TLS session stats");
171 #ifdef TCP_OFFLOAD
172 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, toe, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
173     "TOE TLS session stats");
174 #endif
175 
176 static counter_u64_t ktls_sw_cbc;
177 SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, cbc, CTLFLAG_RD, &ktls_sw_cbc,
178     "Active number of software TLS sessions using AES-CBC");
179 
180 static counter_u64_t ktls_sw_gcm;
181 SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, gcm, CTLFLAG_RD, &ktls_sw_gcm,
182     "Active number of software TLS sessions using AES-GCM");
183 
184 static counter_u64_t ktls_ifnet_cbc;
185 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, cbc, CTLFLAG_RD,
186     &ktls_ifnet_cbc,
187     "Active number of ifnet TLS sessions using AES-CBC");
188 
189 static counter_u64_t ktls_ifnet_gcm;
190 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, gcm, CTLFLAG_RD,
191     &ktls_ifnet_gcm,
192     "Active number of ifnet TLS sessions using AES-GCM");
193 
194 static counter_u64_t ktls_ifnet_reset;
195 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset, CTLFLAG_RD,
196     &ktls_ifnet_reset, "TLS sessions updated to a new ifnet send tag");
197 
198 static counter_u64_t ktls_ifnet_reset_dropped;
199 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset_dropped, CTLFLAG_RD,
200     &ktls_ifnet_reset_dropped,
201     "TLS sessions dropped after failing to update ifnet send tag");
202 
203 static counter_u64_t ktls_ifnet_reset_failed;
204 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset_failed, CTLFLAG_RD,
205     &ktls_ifnet_reset_failed,
206     "TLS sessions that failed to allocate a new ifnet send tag");
207 
208 static int ktls_ifnet_permitted;
209 SYSCTL_UINT(_kern_ipc_tls_ifnet, OID_AUTO, permitted, CTLFLAG_RWTUN,
210     &ktls_ifnet_permitted, 1,
211     "Whether to permit hardware (ifnet) TLS sessions");
212 
213 #ifdef TCP_OFFLOAD
214 static counter_u64_t ktls_toe_cbc;
215 SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, cbc, CTLFLAG_RD,
216     &ktls_toe_cbc,
217     "Active number of TOE TLS sessions using AES-CBC");
218 
219 static counter_u64_t ktls_toe_gcm;
220 SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, gcm, CTLFLAG_RD,
221     &ktls_toe_gcm,
222     "Active number of TOE TLS sessions using AES-GCM");
223 #endif
224 
225 static MALLOC_DEFINE(M_KTLS, "ktls", "Kernel TLS");
226 
227 static void ktls_cleanup(struct ktls_session *tls);
228 #if defined(INET) || defined(INET6)
229 static void ktls_reset_send_tag(void *context, int pending);
230 #endif
231 static void ktls_work_thread(void *ctx);
232 
233 int
234 ktls_crypto_backend_register(struct ktls_crypto_backend *be)
235 {
236 	struct ktls_crypto_backend *curr_be, *tmp;
237 
238 	if (be->api_version != KTLS_API_VERSION) {
239 		printf("KTLS: API version mismatch (%d vs %d) for %s\n",
240 		    be->api_version, KTLS_API_VERSION,
241 		    be->name);
242 		return (EINVAL);
243 	}
244 
245 	rm_wlock(&ktls_backends_lock);
246 	printf("KTLS: Registering crypto method %s with prio %d\n",
247 	       be->name, be->prio);
248 	if (LIST_EMPTY(&ktls_backends)) {
249 		LIST_INSERT_HEAD(&ktls_backends, be, next);
250 	} else {
251 		LIST_FOREACH_SAFE(curr_be, &ktls_backends, next, tmp) {
252 			if (curr_be->prio < be->prio) {
253 				LIST_INSERT_BEFORE(curr_be, be, next);
254 				break;
255 			}
256 			if (LIST_NEXT(curr_be, next) == NULL) {
257 				LIST_INSERT_AFTER(curr_be, be, next);
258 				break;
259 			}
260 		}
261 	}
262 	rm_wunlock(&ktls_backends_lock);
263 	return (0);
264 }
265 
266 int
267 ktls_crypto_backend_deregister(struct ktls_crypto_backend *be)
268 {
269 	struct ktls_crypto_backend *tmp;
270 
271 	/*
272 	 * Don't error if the backend isn't registered.  This permits
273 	 * MOD_UNLOAD handlers to use this function unconditionally.
274 	 */
275 	rm_wlock(&ktls_backends_lock);
276 	LIST_FOREACH(tmp, &ktls_backends, next) {
277 		if (tmp == be)
278 			break;
279 	}
280 	if (tmp == NULL) {
281 		rm_wunlock(&ktls_backends_lock);
282 		return (0);
283 	}
284 
285 	if (!ktls_allow_unload) {
286 		rm_wunlock(&ktls_backends_lock);
287 		printf(
288 		    "KTLS: Deregistering crypto method %s is not supported\n",
289 		    be->name);
290 		return (EBUSY);
291 	}
292 
293 	if (be->use_count) {
294 		rm_wunlock(&ktls_backends_lock);
295 		return (EBUSY);
296 	}
297 
298 	LIST_REMOVE(be, next);
299 	rm_wunlock(&ktls_backends_lock);
300 	return (0);
301 }
302 
303 #if defined(INET) || defined(INET6)
304 static u_int
305 ktls_get_cpu(struct socket *so)
306 {
307 	struct inpcb *inp;
308 	u_int cpuid;
309 
310 	inp = sotoinpcb(so);
311 #ifdef RSS
312 	cpuid = rss_hash2cpuid(inp->inp_flowid, inp->inp_flowtype);
313 	if (cpuid != NETISR_CPUID_NONE)
314 		return (cpuid);
315 #endif
316 	/*
317 	 * Just use the flowid to shard connections in a repeatable
318 	 * fashion.  Note that some crypto backends rely on the
319 	 * serialization provided by having the same connection use
320 	 * the same queue.
321 	 */
322 	cpuid = ktls_cpuid_lookup[inp->inp_flowid % ktls_number_threads];
323 	return (cpuid);
324 }
325 #endif
326 
327 static void
328 ktls_init(void *dummy __unused)
329 {
330 	struct thread *td;
331 	struct pcpu *pc;
332 	cpuset_t mask;
333 	int error, i;
334 
335 	ktls_tasks_active = counter_u64_alloc(M_WAITOK);
336 	ktls_cnt_on = counter_u64_alloc(M_WAITOK);
337 	ktls_offload_total = counter_u64_alloc(M_WAITOK);
338 	ktls_offload_enable_calls = counter_u64_alloc(M_WAITOK);
339 	ktls_offload_active = counter_u64_alloc(M_WAITOK);
340 	ktls_offload_failed_crypto = counter_u64_alloc(M_WAITOK);
341 	ktls_switch_to_ifnet = counter_u64_alloc(M_WAITOK);
342 	ktls_switch_to_sw = counter_u64_alloc(M_WAITOK);
343 	ktls_switch_failed = counter_u64_alloc(M_WAITOK);
344 	ktls_sw_cbc = counter_u64_alloc(M_WAITOK);
345 	ktls_sw_gcm = counter_u64_alloc(M_WAITOK);
346 	ktls_ifnet_cbc = counter_u64_alloc(M_WAITOK);
347 	ktls_ifnet_gcm = counter_u64_alloc(M_WAITOK);
348 	ktls_ifnet_reset = counter_u64_alloc(M_WAITOK);
349 	ktls_ifnet_reset_dropped = counter_u64_alloc(M_WAITOK);
350 	ktls_ifnet_reset_failed = counter_u64_alloc(M_WAITOK);
351 #ifdef TCP_OFFLOAD
352 	ktls_toe_cbc = counter_u64_alloc(M_WAITOK);
353 	ktls_toe_gcm = counter_u64_alloc(M_WAITOK);
354 #endif
355 
356 	rm_init(&ktls_backends_lock, "ktls backends");
357 	LIST_INIT(&ktls_backends);
358 
359 	ktls_wq = malloc(sizeof(*ktls_wq) * (mp_maxid + 1), M_KTLS,
360 	    M_WAITOK | M_ZERO);
361 
362 	ktls_session_zone = uma_zcreate("ktls_session",
363 	    sizeof(struct ktls_session),
364 	    NULL, NULL, NULL, NULL,
365 	    UMA_ALIGN_CACHE, 0);
366 
367 	/*
368 	 * Initialize the workqueues to run the TLS work.  We create a
369 	 * work queue for each CPU.
370 	 */
371 	CPU_FOREACH(i) {
372 		STAILQ_INIT(&ktls_wq[i].head);
373 		mtx_init(&ktls_wq[i].mtx, "ktls work queue", NULL, MTX_DEF);
374 		error = kproc_kthread_add(ktls_work_thread, &ktls_wq[i],
375 		    &ktls_proc, &td, 0, 0, "KTLS", "thr_%d", i);
376 		if (error)
377 			panic("Can't add KTLS thread %d error %d", i, error);
378 
379 		/*
380 		 * Bind threads to cores.  If ktls_bind_threads is >
381 		 * 1, then we bind to the NUMA domain.
382 		 */
383 		if (ktls_bind_threads) {
384 			if (ktls_bind_threads > 1) {
385 				pc = pcpu_find(i);
386 				CPU_COPY(&cpuset_domain[pc->pc_domain], &mask);
387 			} else {
388 				CPU_SETOF(i, &mask);
389 			}
390 			error = cpuset_setthread(td->td_tid, &mask);
391 			if (error)
392 				panic(
393 			    "Unable to bind KTLS thread for CPU %d error %d",
394 				     i, error);
395 		}
396 		ktls_cpuid_lookup[ktls_number_threads] = i;
397 		ktls_number_threads++;
398 	}
399 	printf("KTLS: Initialized %d threads\n", ktls_number_threads);
400 }
401 SYSINIT(ktls, SI_SUB_SMP + 1, SI_ORDER_ANY, ktls_init, NULL);
402 
403 #if defined(INET) || defined(INET6)
404 static int
405 ktls_create_session(struct socket *so, struct tls_enable *en,
406     struct ktls_session **tlsp)
407 {
408 	struct ktls_session *tls;
409 	int error;
410 
411 	/* Only TLS 1.0 - 1.3 are supported. */
412 	if (en->tls_vmajor != TLS_MAJOR_VER_ONE)
413 		return (EINVAL);
414 	if (en->tls_vminor < TLS_MINOR_VER_ZERO ||
415 	    en->tls_vminor > TLS_MINOR_VER_THREE)
416 		return (EINVAL);
417 
418 	if (en->auth_key_len < 0 || en->auth_key_len > TLS_MAX_PARAM_SIZE)
419 		return (EINVAL);
420 	if (en->cipher_key_len < 0 || en->cipher_key_len > TLS_MAX_PARAM_SIZE)
421 		return (EINVAL);
422 	if (en->iv_len < 0 || en->iv_len > sizeof(tls->params.iv))
423 		return (EINVAL);
424 
425 	/* All supported algorithms require a cipher key. */
426 	if (en->cipher_key_len == 0)
427 		return (EINVAL);
428 
429 	/* No flags are currently supported. */
430 	if (en->flags != 0)
431 		return (EINVAL);
432 
433 	/* Common checks for supported algorithms. */
434 	switch (en->cipher_algorithm) {
435 	case CRYPTO_AES_NIST_GCM_16:
436 		/*
437 		 * auth_algorithm isn't used, but permit GMAC values
438 		 * for compatibility.
439 		 */
440 		switch (en->auth_algorithm) {
441 		case 0:
442 #ifdef COMPAT_FREEBSD12
443 		/* XXX: Really 13.0-current COMPAT. */
444 		case CRYPTO_AES_128_NIST_GMAC:
445 		case CRYPTO_AES_192_NIST_GMAC:
446 		case CRYPTO_AES_256_NIST_GMAC:
447 #endif
448 			break;
449 		default:
450 			return (EINVAL);
451 		}
452 		if (en->auth_key_len != 0)
453 			return (EINVAL);
454 		if ((en->tls_vminor == TLS_MINOR_VER_TWO &&
455 			en->iv_len != TLS_AEAD_GCM_LEN) ||
456 		    (en->tls_vminor == TLS_MINOR_VER_THREE &&
457 			en->iv_len != TLS_1_3_GCM_IV_LEN))
458 			return (EINVAL);
459 		break;
460 	case CRYPTO_AES_CBC:
461 		switch (en->auth_algorithm) {
462 		case CRYPTO_SHA1_HMAC:
463 			/*
464 			 * TLS 1.0 requires an implicit IV.  TLS 1.1+
465 			 * all use explicit IVs.
466 			 */
467 			if (en->tls_vminor == TLS_MINOR_VER_ZERO) {
468 				if (en->iv_len != TLS_CBC_IMPLICIT_IV_LEN)
469 					return (EINVAL);
470 				break;
471 			}
472 
473 			/* FALLTHROUGH */
474 		case CRYPTO_SHA2_256_HMAC:
475 		case CRYPTO_SHA2_384_HMAC:
476 			/* Ignore any supplied IV. */
477 			en->iv_len = 0;
478 			break;
479 		default:
480 			return (EINVAL);
481 		}
482 		if (en->auth_key_len == 0)
483 			return (EINVAL);
484 		break;
485 	default:
486 		return (EINVAL);
487 	}
488 
489 	tls = uma_zalloc(ktls_session_zone, M_WAITOK | M_ZERO);
490 
491 	counter_u64_add(ktls_offload_active, 1);
492 
493 	refcount_init(&tls->refcount, 1);
494 	TASK_INIT(&tls->reset_tag_task, 0, ktls_reset_send_tag, tls);
495 
496 	tls->wq_index = ktls_get_cpu(so);
497 
498 	tls->params.cipher_algorithm = en->cipher_algorithm;
499 	tls->params.auth_algorithm = en->auth_algorithm;
500 	tls->params.tls_vmajor = en->tls_vmajor;
501 	tls->params.tls_vminor = en->tls_vminor;
502 	tls->params.flags = en->flags;
503 	tls->params.max_frame_len = min(TLS_MAX_MSG_SIZE_V10_2, ktls_maxlen);
504 
505 	/* Set the header and trailer lengths. */
506 	tls->params.tls_hlen = sizeof(struct tls_record_layer);
507 	switch (en->cipher_algorithm) {
508 	case CRYPTO_AES_NIST_GCM_16:
509 		/*
510 		 * TLS 1.2 uses a 4 byte implicit IV with an explicit 8 byte
511 		 * nonce.  TLS 1.3 uses a 12 byte implicit IV.
512 		 */
513 		if (en->tls_vminor < TLS_MINOR_VER_THREE)
514 			tls->params.tls_hlen += sizeof(uint64_t);
515 		tls->params.tls_tlen = AES_GMAC_HASH_LEN;
516 
517 		/*
518 		 * TLS 1.3 includes optional padding which we
519 		 * do not support, and also puts the "real" record
520 		 * type at the end of the encrypted data.
521 		 */
522 		if (en->tls_vminor == TLS_MINOR_VER_THREE)
523 			tls->params.tls_tlen += sizeof(uint8_t);
524 
525 		tls->params.tls_bs = 1;
526 		break;
527 	case CRYPTO_AES_CBC:
528 		switch (en->auth_algorithm) {
529 		case CRYPTO_SHA1_HMAC:
530 			if (en->tls_vminor == TLS_MINOR_VER_ZERO) {
531 				/* Implicit IV, no nonce. */
532 			} else {
533 				tls->params.tls_hlen += AES_BLOCK_LEN;
534 			}
535 			tls->params.tls_tlen = AES_BLOCK_LEN +
536 			    SHA1_HASH_LEN;
537 			break;
538 		case CRYPTO_SHA2_256_HMAC:
539 			tls->params.tls_hlen += AES_BLOCK_LEN;
540 			tls->params.tls_tlen = AES_BLOCK_LEN +
541 			    SHA2_256_HASH_LEN;
542 			break;
543 		case CRYPTO_SHA2_384_HMAC:
544 			tls->params.tls_hlen += AES_BLOCK_LEN;
545 			tls->params.tls_tlen = AES_BLOCK_LEN +
546 			    SHA2_384_HASH_LEN;
547 			break;
548 		default:
549 			panic("invalid hmac");
550 		}
551 		tls->params.tls_bs = AES_BLOCK_LEN;
552 		break;
553 	default:
554 		panic("invalid cipher");
555 	}
556 
557 	KASSERT(tls->params.tls_hlen <= MBUF_PEXT_HDR_LEN,
558 	    ("TLS header length too long: %d", tls->params.tls_hlen));
559 	KASSERT(tls->params.tls_tlen <= MBUF_PEXT_TRAIL_LEN,
560 	    ("TLS trailer length too long: %d", tls->params.tls_tlen));
561 
562 	if (en->auth_key_len != 0) {
563 		tls->params.auth_key_len = en->auth_key_len;
564 		tls->params.auth_key = malloc(en->auth_key_len, M_KTLS,
565 		    M_WAITOK);
566 		error = copyin(en->auth_key, tls->params.auth_key,
567 		    en->auth_key_len);
568 		if (error)
569 			goto out;
570 	}
571 
572 	tls->params.cipher_key_len = en->cipher_key_len;
573 	tls->params.cipher_key = malloc(en->cipher_key_len, M_KTLS, M_WAITOK);
574 	error = copyin(en->cipher_key, tls->params.cipher_key,
575 	    en->cipher_key_len);
576 	if (error)
577 		goto out;
578 
579 	/*
580 	 * This holds the implicit portion of the nonce for GCM and
581 	 * the initial implicit IV for TLS 1.0.  The explicit portions
582 	 * of the IV are generated in ktls_frame().
583 	 */
584 	if (en->iv_len != 0) {
585 		tls->params.iv_len = en->iv_len;
586 		error = copyin(en->iv, tls->params.iv, en->iv_len);
587 		if (error)
588 			goto out;
589 
590 		/*
591 		 * For TLS 1.2, generate an 8-byte nonce as a counter
592 		 * to generate unique explicit IVs.
593 		 *
594 		 * Store this counter in the last 8 bytes of the IV
595 		 * array so that it is 8-byte aligned.
596 		 */
597 		if (en->cipher_algorithm == CRYPTO_AES_NIST_GCM_16 &&
598 		    en->tls_vminor == TLS_MINOR_VER_TWO)
599 			arc4rand(tls->params.iv + 8, sizeof(uint64_t), 0);
600 	}
601 
602 	*tlsp = tls;
603 	return (0);
604 
605 out:
606 	ktls_cleanup(tls);
607 	return (error);
608 }
609 
610 static struct ktls_session *
611 ktls_clone_session(struct ktls_session *tls)
612 {
613 	struct ktls_session *tls_new;
614 
615 	tls_new = uma_zalloc(ktls_session_zone, M_WAITOK | M_ZERO);
616 
617 	counter_u64_add(ktls_offload_active, 1);
618 
619 	refcount_init(&tls_new->refcount, 1);
620 
621 	/* Copy fields from existing session. */
622 	tls_new->params = tls->params;
623 	tls_new->wq_index = tls->wq_index;
624 
625 	/* Deep copy keys. */
626 	if (tls_new->params.auth_key != NULL) {
627 		tls_new->params.auth_key = malloc(tls->params.auth_key_len,
628 		    M_KTLS, M_WAITOK);
629 		memcpy(tls_new->params.auth_key, tls->params.auth_key,
630 		    tls->params.auth_key_len);
631 	}
632 
633 	tls_new->params.cipher_key = malloc(tls->params.cipher_key_len, M_KTLS,
634 	    M_WAITOK);
635 	memcpy(tls_new->params.cipher_key, tls->params.cipher_key,
636 	    tls->params.cipher_key_len);
637 
638 	return (tls_new);
639 }
640 #endif
641 
642 static void
643 ktls_cleanup(struct ktls_session *tls)
644 {
645 
646 	counter_u64_add(ktls_offload_active, -1);
647 	switch (tls->mode) {
648 	case TCP_TLS_MODE_SW:
649 		MPASS(tls->be != NULL);
650 		switch (tls->params.cipher_algorithm) {
651 		case CRYPTO_AES_CBC:
652 			counter_u64_add(ktls_sw_cbc, -1);
653 			break;
654 		case CRYPTO_AES_NIST_GCM_16:
655 			counter_u64_add(ktls_sw_gcm, -1);
656 			break;
657 		}
658 		tls->free(tls);
659 		break;
660 	case TCP_TLS_MODE_IFNET:
661 		switch (tls->params.cipher_algorithm) {
662 		case CRYPTO_AES_CBC:
663 			counter_u64_add(ktls_ifnet_cbc, -1);
664 			break;
665 		case CRYPTO_AES_NIST_GCM_16:
666 			counter_u64_add(ktls_ifnet_gcm, -1);
667 			break;
668 		}
669 		m_snd_tag_rele(tls->snd_tag);
670 		break;
671 #ifdef TCP_OFFLOAD
672 	case TCP_TLS_MODE_TOE:
673 		switch (tls->params.cipher_algorithm) {
674 		case CRYPTO_AES_CBC:
675 			counter_u64_add(ktls_toe_cbc, -1);
676 			break;
677 		case CRYPTO_AES_NIST_GCM_16:
678 			counter_u64_add(ktls_toe_gcm, -1);
679 			break;
680 		}
681 		break;
682 #endif
683 	}
684 	if (tls->params.auth_key != NULL) {
685 		explicit_bzero(tls->params.auth_key, tls->params.auth_key_len);
686 		free(tls->params.auth_key, M_KTLS);
687 		tls->params.auth_key = NULL;
688 		tls->params.auth_key_len = 0;
689 	}
690 	if (tls->params.cipher_key != NULL) {
691 		explicit_bzero(tls->params.cipher_key,
692 		    tls->params.cipher_key_len);
693 		free(tls->params.cipher_key, M_KTLS);
694 		tls->params.cipher_key = NULL;
695 		tls->params.cipher_key_len = 0;
696 	}
697 	explicit_bzero(tls->params.iv, sizeof(tls->params.iv));
698 }
699 
700 #if defined(INET) || defined(INET6)
701 
702 #ifdef TCP_OFFLOAD
703 static int
704 ktls_try_toe(struct socket *so, struct ktls_session *tls, int direction)
705 {
706 	struct inpcb *inp;
707 	struct tcpcb *tp;
708 	int error;
709 
710 	inp = so->so_pcb;
711 	INP_WLOCK(inp);
712 	if (inp->inp_flags2 & INP_FREED) {
713 		INP_WUNLOCK(inp);
714 		return (ECONNRESET);
715 	}
716 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
717 		INP_WUNLOCK(inp);
718 		return (ECONNRESET);
719 	}
720 	if (inp->inp_socket == NULL) {
721 		INP_WUNLOCK(inp);
722 		return (ECONNRESET);
723 	}
724 	tp = intotcpcb(inp);
725 	if (tp->tod == NULL) {
726 		INP_WUNLOCK(inp);
727 		return (EOPNOTSUPP);
728 	}
729 
730 	error = tcp_offload_alloc_tls_session(tp, tls, direction);
731 	INP_WUNLOCK(inp);
732 	if (error == 0) {
733 		tls->mode = TCP_TLS_MODE_TOE;
734 		switch (tls->params.cipher_algorithm) {
735 		case CRYPTO_AES_CBC:
736 			counter_u64_add(ktls_toe_cbc, 1);
737 			break;
738 		case CRYPTO_AES_NIST_GCM_16:
739 			counter_u64_add(ktls_toe_gcm, 1);
740 			break;
741 		}
742 	}
743 	return (error);
744 }
745 #endif
746 
747 /*
748  * Common code used when first enabling ifnet TLS on a connection or
749  * when allocating a new ifnet TLS session due to a routing change.
750  * This function allocates a new TLS send tag on whatever interface
751  * the connection is currently routed over.
752  */
753 static int
754 ktls_alloc_snd_tag(struct inpcb *inp, struct ktls_session *tls, bool force,
755     struct m_snd_tag **mstp)
756 {
757 	union if_snd_tag_alloc_params params;
758 	struct ifnet *ifp;
759 	struct nhop_object *nh;
760 	struct tcpcb *tp;
761 	int error;
762 
763 	INP_RLOCK(inp);
764 	if (inp->inp_flags2 & INP_FREED) {
765 		INP_RUNLOCK(inp);
766 		return (ECONNRESET);
767 	}
768 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
769 		INP_RUNLOCK(inp);
770 		return (ECONNRESET);
771 	}
772 	if (inp->inp_socket == NULL) {
773 		INP_RUNLOCK(inp);
774 		return (ECONNRESET);
775 	}
776 	tp = intotcpcb(inp);
777 
778 	/*
779 	 * Check administrative controls on ifnet TLS to determine if
780 	 * ifnet TLS should be denied.
781 	 *
782 	 * - Always permit 'force' requests.
783 	 * - ktls_ifnet_permitted == 0: always deny.
784 	 */
785 	if (!force && ktls_ifnet_permitted == 0) {
786 		INP_RUNLOCK(inp);
787 		return (ENXIO);
788 	}
789 
790 	/*
791 	 * XXX: Use the cached route in the inpcb to find the
792 	 * interface.  This should perhaps instead use
793 	 * rtalloc1_fib(dst, 0, 0, fibnum).  Since KTLS is only
794 	 * enabled after a connection has completed key negotiation in
795 	 * userland, the cached route will be present in practice.
796 	 */
797 	nh = inp->inp_route.ro_nh;
798 	if (nh == NULL) {
799 		INP_RUNLOCK(inp);
800 		return (ENXIO);
801 	}
802 	ifp = nh->nh_ifp;
803 	if_ref(ifp);
804 
805 	params.hdr.type = IF_SND_TAG_TYPE_TLS;
806 	params.hdr.flowid = inp->inp_flowid;
807 	params.hdr.flowtype = inp->inp_flowtype;
808 	params.hdr.numa_domain = inp->inp_numa_domain;
809 	params.tls.inp = inp;
810 	params.tls.tls = tls;
811 	INP_RUNLOCK(inp);
812 
813 	if (ifp->if_snd_tag_alloc == NULL) {
814 		error = EOPNOTSUPP;
815 		goto out;
816 	}
817 	if ((ifp->if_capenable & IFCAP_NOMAP) == 0) {
818 		error = EOPNOTSUPP;
819 		goto out;
820 	}
821 	if (inp->inp_vflag & INP_IPV6) {
822 		if ((ifp->if_capenable & IFCAP_TXTLS6) == 0) {
823 			error = EOPNOTSUPP;
824 			goto out;
825 		}
826 	} else {
827 		if ((ifp->if_capenable & IFCAP_TXTLS4) == 0) {
828 			error = EOPNOTSUPP;
829 			goto out;
830 		}
831 	}
832 	error = ifp->if_snd_tag_alloc(ifp, &params, mstp);
833 out:
834 	if_rele(ifp);
835 	return (error);
836 }
837 
838 static int
839 ktls_try_ifnet(struct socket *so, struct ktls_session *tls, bool force)
840 {
841 	struct m_snd_tag *mst;
842 	int error;
843 
844 	error = ktls_alloc_snd_tag(so->so_pcb, tls, force, &mst);
845 	if (error == 0) {
846 		tls->mode = TCP_TLS_MODE_IFNET;
847 		tls->snd_tag = mst;
848 		switch (tls->params.cipher_algorithm) {
849 		case CRYPTO_AES_CBC:
850 			counter_u64_add(ktls_ifnet_cbc, 1);
851 			break;
852 		case CRYPTO_AES_NIST_GCM_16:
853 			counter_u64_add(ktls_ifnet_gcm, 1);
854 			break;
855 		}
856 	}
857 	return (error);
858 }
859 
860 static int
861 ktls_try_sw(struct socket *so, struct ktls_session *tls)
862 {
863 	struct rm_priotracker prio;
864 	struct ktls_crypto_backend *be;
865 
866 	/*
867 	 * Choose the best software crypto backend.  Backends are
868 	 * stored in sorted priority order (larget value == most
869 	 * important at the head of the list), so this just stops on
870 	 * the first backend that claims the session by returning
871 	 * success.
872 	 */
873 	if (ktls_allow_unload)
874 		rm_rlock(&ktls_backends_lock, &prio);
875 	LIST_FOREACH(be, &ktls_backends, next) {
876 		if (be->try(so, tls) == 0)
877 			break;
878 		KASSERT(tls->cipher == NULL,
879 		    ("ktls backend leaked a cipher pointer"));
880 	}
881 	if (be != NULL) {
882 		if (ktls_allow_unload)
883 			be->use_count++;
884 		tls->be = be;
885 	}
886 	if (ktls_allow_unload)
887 		rm_runlock(&ktls_backends_lock, &prio);
888 	if (be == NULL)
889 		return (EOPNOTSUPP);
890 	tls->mode = TCP_TLS_MODE_SW;
891 	switch (tls->params.cipher_algorithm) {
892 	case CRYPTO_AES_CBC:
893 		counter_u64_add(ktls_sw_cbc, 1);
894 		break;
895 	case CRYPTO_AES_NIST_GCM_16:
896 		counter_u64_add(ktls_sw_gcm, 1);
897 		break;
898 	}
899 	return (0);
900 }
901 
902 int
903 ktls_enable_rx(struct socket *so, struct tls_enable *en)
904 {
905 	struct ktls_session *tls;
906 	int error;
907 
908 	if (!ktls_offload_enable)
909 		return (ENOTSUP);
910 
911 	counter_u64_add(ktls_offload_enable_calls, 1);
912 
913 	/*
914 	 * This should always be true since only the TCP socket option
915 	 * invokes this function.
916 	 */
917 	if (so->so_proto->pr_protocol != IPPROTO_TCP)
918 		return (EINVAL);
919 
920 	/*
921 	 * XXX: Don't overwrite existing sessions.  We should permit
922 	 * this to support rekeying in the future.
923 	 */
924 	if (so->so_rcv.sb_tls_info != NULL)
925 		return (EALREADY);
926 
927 	if (en->cipher_algorithm == CRYPTO_AES_CBC && !ktls_cbc_enable)
928 		return (ENOTSUP);
929 
930 	error = ktls_create_session(so, en, &tls);
931 	if (error)
932 		return (error);
933 
934 	/* TLS RX offload is only supported on TOE currently. */
935 #ifdef TCP_OFFLOAD
936 	error = ktls_try_toe(so, tls, KTLS_RX);
937 #else
938 	error = EOPNOTSUPP;
939 #endif
940 
941 	if (error) {
942 		ktls_cleanup(tls);
943 		return (error);
944 	}
945 
946 	/* Mark the socket as using TLS offload. */
947 	SOCKBUF_LOCK(&so->so_rcv);
948 	so->so_rcv.sb_tls_info = tls;
949 	SOCKBUF_UNLOCK(&so->so_rcv);
950 
951 	counter_u64_add(ktls_offload_total, 1);
952 
953 	return (0);
954 }
955 
956 int
957 ktls_enable_tx(struct socket *so, struct tls_enable *en)
958 {
959 	struct ktls_session *tls;
960 	int error;
961 
962 	if (!ktls_offload_enable)
963 		return (ENOTSUP);
964 
965 	counter_u64_add(ktls_offload_enable_calls, 1);
966 
967 	/*
968 	 * This should always be true since only the TCP socket option
969 	 * invokes this function.
970 	 */
971 	if (so->so_proto->pr_protocol != IPPROTO_TCP)
972 		return (EINVAL);
973 
974 	/*
975 	 * XXX: Don't overwrite existing sessions.  We should permit
976 	 * this to support rekeying in the future.
977 	 */
978 	if (so->so_snd.sb_tls_info != NULL)
979 		return (EALREADY);
980 
981 	if (en->cipher_algorithm == CRYPTO_AES_CBC && !ktls_cbc_enable)
982 		return (ENOTSUP);
983 
984 	/* TLS requires ext pgs */
985 	if (mb_use_ext_pgs == 0)
986 		return (ENXIO);
987 
988 	error = ktls_create_session(so, en, &tls);
989 	if (error)
990 		return (error);
991 
992 	/* Prefer TOE -> ifnet TLS -> software TLS. */
993 #ifdef TCP_OFFLOAD
994 	error = ktls_try_toe(so, tls, KTLS_TX);
995 	if (error)
996 #endif
997 		error = ktls_try_ifnet(so, tls, false);
998 	if (error)
999 		error = ktls_try_sw(so, tls);
1000 
1001 	if (error) {
1002 		ktls_cleanup(tls);
1003 		return (error);
1004 	}
1005 
1006 	error = sblock(&so->so_snd, SBL_WAIT);
1007 	if (error) {
1008 		ktls_cleanup(tls);
1009 		return (error);
1010 	}
1011 
1012 	SOCKBUF_LOCK(&so->so_snd);
1013 	so->so_snd.sb_tls_seqno = be64dec(en->rec_seq);
1014 	so->so_snd.sb_tls_info = tls;
1015 	if (tls->mode != TCP_TLS_MODE_SW)
1016 		so->so_snd.sb_flags |= SB_TLS_IFNET;
1017 	SOCKBUF_UNLOCK(&so->so_snd);
1018 	sbunlock(&so->so_snd);
1019 
1020 	counter_u64_add(ktls_offload_total, 1);
1021 
1022 	return (0);
1023 }
1024 
1025 int
1026 ktls_get_rx_mode(struct socket *so)
1027 {
1028 	struct ktls_session *tls;
1029 	struct inpcb *inp;
1030 	int mode;
1031 
1032 	inp = so->so_pcb;
1033 	INP_WLOCK_ASSERT(inp);
1034 	SOCKBUF_LOCK(&so->so_rcv);
1035 	tls = so->so_rcv.sb_tls_info;
1036 	if (tls == NULL)
1037 		mode = TCP_TLS_MODE_NONE;
1038 	else
1039 		mode = tls->mode;
1040 	SOCKBUF_UNLOCK(&so->so_rcv);
1041 	return (mode);
1042 }
1043 
1044 int
1045 ktls_get_tx_mode(struct socket *so)
1046 {
1047 	struct ktls_session *tls;
1048 	struct inpcb *inp;
1049 	int mode;
1050 
1051 	inp = so->so_pcb;
1052 	INP_WLOCK_ASSERT(inp);
1053 	SOCKBUF_LOCK(&so->so_snd);
1054 	tls = so->so_snd.sb_tls_info;
1055 	if (tls == NULL)
1056 		mode = TCP_TLS_MODE_NONE;
1057 	else
1058 		mode = tls->mode;
1059 	SOCKBUF_UNLOCK(&so->so_snd);
1060 	return (mode);
1061 }
1062 
1063 /*
1064  * Switch between SW and ifnet TLS sessions as requested.
1065  */
1066 int
1067 ktls_set_tx_mode(struct socket *so, int mode)
1068 {
1069 	struct ktls_session *tls, *tls_new;
1070 	struct inpcb *inp;
1071 	int error;
1072 
1073 	switch (mode) {
1074 	case TCP_TLS_MODE_SW:
1075 	case TCP_TLS_MODE_IFNET:
1076 		break;
1077 	default:
1078 		return (EINVAL);
1079 	}
1080 
1081 	inp = so->so_pcb;
1082 	INP_WLOCK_ASSERT(inp);
1083 	SOCKBUF_LOCK(&so->so_snd);
1084 	tls = so->so_snd.sb_tls_info;
1085 	if (tls == NULL) {
1086 		SOCKBUF_UNLOCK(&so->so_snd);
1087 		return (0);
1088 	}
1089 
1090 	if (tls->mode == mode) {
1091 		SOCKBUF_UNLOCK(&so->so_snd);
1092 		return (0);
1093 	}
1094 
1095 	tls = ktls_hold(tls);
1096 	SOCKBUF_UNLOCK(&so->so_snd);
1097 	INP_WUNLOCK(inp);
1098 
1099 	tls_new = ktls_clone_session(tls);
1100 
1101 	if (mode == TCP_TLS_MODE_IFNET)
1102 		error = ktls_try_ifnet(so, tls_new, true);
1103 	else
1104 		error = ktls_try_sw(so, tls_new);
1105 	if (error) {
1106 		counter_u64_add(ktls_switch_failed, 1);
1107 		ktls_free(tls_new);
1108 		ktls_free(tls);
1109 		INP_WLOCK(inp);
1110 		return (error);
1111 	}
1112 
1113 	error = sblock(&so->so_snd, SBL_WAIT);
1114 	if (error) {
1115 		counter_u64_add(ktls_switch_failed, 1);
1116 		ktls_free(tls_new);
1117 		ktls_free(tls);
1118 		INP_WLOCK(inp);
1119 		return (error);
1120 	}
1121 
1122 	/*
1123 	 * If we raced with another session change, keep the existing
1124 	 * session.
1125 	 */
1126 	if (tls != so->so_snd.sb_tls_info) {
1127 		counter_u64_add(ktls_switch_failed, 1);
1128 		sbunlock(&so->so_snd);
1129 		ktls_free(tls_new);
1130 		ktls_free(tls);
1131 		INP_WLOCK(inp);
1132 		return (EBUSY);
1133 	}
1134 
1135 	SOCKBUF_LOCK(&so->so_snd);
1136 	so->so_snd.sb_tls_info = tls_new;
1137 	if (tls_new->mode != TCP_TLS_MODE_SW)
1138 		so->so_snd.sb_flags |= SB_TLS_IFNET;
1139 	SOCKBUF_UNLOCK(&so->so_snd);
1140 	sbunlock(&so->so_snd);
1141 
1142 	/*
1143 	 * Drop two references on 'tls'.  The first is for the
1144 	 * ktls_hold() above.  The second drops the reference from the
1145 	 * socket buffer.
1146 	 */
1147 	KASSERT(tls->refcount >= 2, ("too few references on old session"));
1148 	ktls_free(tls);
1149 	ktls_free(tls);
1150 
1151 	if (mode == TCP_TLS_MODE_IFNET)
1152 		counter_u64_add(ktls_switch_to_ifnet, 1);
1153 	else
1154 		counter_u64_add(ktls_switch_to_sw, 1);
1155 
1156 	INP_WLOCK(inp);
1157 	return (0);
1158 }
1159 
1160 /*
1161  * Try to allocate a new TLS send tag.  This task is scheduled when
1162  * ip_output detects a route change while trying to transmit a packet
1163  * holding a TLS record.  If a new tag is allocated, replace the tag
1164  * in the TLS session.  Subsequent packets on the connection will use
1165  * the new tag.  If a new tag cannot be allocated, drop the
1166  * connection.
1167  */
1168 static void
1169 ktls_reset_send_tag(void *context, int pending)
1170 {
1171 	struct epoch_tracker et;
1172 	struct ktls_session *tls;
1173 	struct m_snd_tag *old, *new;
1174 	struct inpcb *inp;
1175 	struct tcpcb *tp;
1176 	int error;
1177 
1178 	MPASS(pending == 1);
1179 
1180 	tls = context;
1181 	inp = tls->inp;
1182 
1183 	/*
1184 	 * Free the old tag first before allocating a new one.
1185 	 * ip[6]_output_send() will treat a NULL send tag the same as
1186 	 * an ifp mismatch and drop packets until a new tag is
1187 	 * allocated.
1188 	 *
1189 	 * Write-lock the INP when changing tls->snd_tag since
1190 	 * ip[6]_output_send() holds a read-lock when reading the
1191 	 * pointer.
1192 	 */
1193 	INP_WLOCK(inp);
1194 	old = tls->snd_tag;
1195 	tls->snd_tag = NULL;
1196 	INP_WUNLOCK(inp);
1197 	if (old != NULL)
1198 		m_snd_tag_rele(old);
1199 
1200 	error = ktls_alloc_snd_tag(inp, tls, true, &new);
1201 
1202 	if (error == 0) {
1203 		INP_WLOCK(inp);
1204 		tls->snd_tag = new;
1205 		mtx_pool_lock(mtxpool_sleep, tls);
1206 		tls->reset_pending = false;
1207 		mtx_pool_unlock(mtxpool_sleep, tls);
1208 		if (!in_pcbrele_wlocked(inp))
1209 			INP_WUNLOCK(inp);
1210 
1211 		counter_u64_add(ktls_ifnet_reset, 1);
1212 
1213 		/*
1214 		 * XXX: Should we kick tcp_output explicitly now that
1215 		 * the send tag is fixed or just rely on timers?
1216 		 */
1217 	} else {
1218 		NET_EPOCH_ENTER(et);
1219 		INP_WLOCK(inp);
1220 		if (!in_pcbrele_wlocked(inp)) {
1221 			if (!(inp->inp_flags & INP_TIMEWAIT) &&
1222 			    !(inp->inp_flags & INP_DROPPED)) {
1223 				tp = intotcpcb(inp);
1224 				CURVNET_SET(tp->t_vnet);
1225 				tp = tcp_drop(tp, ECONNABORTED);
1226 				CURVNET_RESTORE();
1227 				if (tp != NULL)
1228 					INP_WUNLOCK(inp);
1229 				counter_u64_add(ktls_ifnet_reset_dropped, 1);
1230 			} else
1231 				INP_WUNLOCK(inp);
1232 		}
1233 		NET_EPOCH_EXIT(et);
1234 
1235 		counter_u64_add(ktls_ifnet_reset_failed, 1);
1236 
1237 		/*
1238 		 * Leave reset_pending true to avoid future tasks while
1239 		 * the socket goes away.
1240 		 */
1241 	}
1242 
1243 	ktls_free(tls);
1244 }
1245 
1246 int
1247 ktls_output_eagain(struct inpcb *inp, struct ktls_session *tls)
1248 {
1249 
1250 	if (inp == NULL)
1251 		return (ENOBUFS);
1252 
1253 	INP_LOCK_ASSERT(inp);
1254 
1255 	/*
1256 	 * See if we should schedule a task to update the send tag for
1257 	 * this session.
1258 	 */
1259 	mtx_pool_lock(mtxpool_sleep, tls);
1260 	if (!tls->reset_pending) {
1261 		(void) ktls_hold(tls);
1262 		in_pcbref(inp);
1263 		tls->inp = inp;
1264 		tls->reset_pending = true;
1265 		taskqueue_enqueue(taskqueue_thread, &tls->reset_tag_task);
1266 	}
1267 	mtx_pool_unlock(mtxpool_sleep, tls);
1268 	return (ENOBUFS);
1269 }
1270 #endif
1271 
1272 void
1273 ktls_destroy(struct ktls_session *tls)
1274 {
1275 	struct rm_priotracker prio;
1276 
1277 	ktls_cleanup(tls);
1278 	if (tls->be != NULL && ktls_allow_unload) {
1279 		rm_rlock(&ktls_backends_lock, &prio);
1280 		tls->be->use_count--;
1281 		rm_runlock(&ktls_backends_lock, &prio);
1282 	}
1283 	uma_zfree(ktls_session_zone, tls);
1284 }
1285 
1286 void
1287 ktls_seq(struct sockbuf *sb, struct mbuf *m)
1288 {
1289 
1290 	for (; m != NULL; m = m->m_next) {
1291 		KASSERT((m->m_flags & M_EXTPG) != 0,
1292 		    ("ktls_seq: mapped mbuf %p", m));
1293 
1294 		m->m_epg_seqno = sb->sb_tls_seqno;
1295 		sb->sb_tls_seqno++;
1296 	}
1297 }
1298 
1299 /*
1300  * Add TLS framing (headers and trailers) to a chain of mbufs.  Each
1301  * mbuf in the chain must be an unmapped mbuf.  The payload of the
1302  * mbuf must be populated with the payload of each TLS record.
1303  *
1304  * The record_type argument specifies the TLS record type used when
1305  * populating the TLS header.
1306  *
1307  * The enq_count argument on return is set to the number of pages of
1308  * payload data for this entire chain that need to be encrypted via SW
1309  * encryption.  The returned value should be passed to ktls_enqueue
1310  * when scheduling encryption of this chain of mbufs.
1311  */
1312 void
1313 ktls_frame(struct mbuf *top, struct ktls_session *tls, int *enq_cnt,
1314     uint8_t record_type)
1315 {
1316 	struct tls_record_layer *tlshdr;
1317 	struct mbuf *m;
1318 	uint64_t *noncep;
1319 	uint16_t tls_len;
1320 	int maxlen;
1321 
1322 	maxlen = tls->params.max_frame_len;
1323 	*enq_cnt = 0;
1324 	for (m = top; m != NULL; m = m->m_next) {
1325 		/*
1326 		 * All mbufs in the chain should be non-empty TLS
1327 		 * records whose payload does not exceed the maximum
1328 		 * frame length.
1329 		 */
1330 		KASSERT(m->m_len <= maxlen && m->m_len > 0,
1331 		    ("ktls_frame: m %p len %d\n", m, m->m_len));
1332 		/*
1333 		 * TLS frames require unmapped mbufs to store session
1334 		 * info.
1335 		 */
1336 		KASSERT((m->m_flags & M_EXTPG) != 0,
1337 		    ("ktls_frame: mapped mbuf %p (top = %p)\n", m, top));
1338 
1339 		tls_len = m->m_len;
1340 
1341 		/* Save a reference to the session. */
1342 		m->m_epg_tls = ktls_hold(tls);
1343 
1344 		m->m_epg_hdrlen = tls->params.tls_hlen;
1345 		m->m_epg_trllen = tls->params.tls_tlen;
1346 		if (tls->params.cipher_algorithm == CRYPTO_AES_CBC) {
1347 			int bs, delta;
1348 
1349 			/*
1350 			 * AES-CBC pads messages to a multiple of the
1351 			 * block size.  Note that the padding is
1352 			 * applied after the digest and the encryption
1353 			 * is done on the "plaintext || mac || padding".
1354 			 * At least one byte of padding is always
1355 			 * present.
1356 			 *
1357 			 * Compute the final trailer length assuming
1358 			 * at most one block of padding.
1359 			 * tls->params.sb_tls_tlen is the maximum
1360 			 * possible trailer length (padding + digest).
1361 			 * delta holds the number of excess padding
1362 			 * bytes if the maximum were used.  Those
1363 			 * extra bytes are removed.
1364 			 */
1365 			bs = tls->params.tls_bs;
1366 			delta = (tls_len + tls->params.tls_tlen) & (bs - 1);
1367 			m->m_epg_trllen -= delta;
1368 		}
1369 		m->m_len += m->m_epg_hdrlen + m->m_epg_trllen;
1370 
1371 		/* Populate the TLS header. */
1372 		tlshdr = (void *)m->m_epg_hdr;
1373 		tlshdr->tls_vmajor = tls->params.tls_vmajor;
1374 
1375 		/*
1376 		 * TLS 1.3 masquarades as TLS 1.2 with a record type
1377 		 * of TLS_RLTYPE_APP.
1378 		 */
1379 		if (tls->params.tls_vminor == TLS_MINOR_VER_THREE &&
1380 		    tls->params.tls_vmajor == TLS_MAJOR_VER_ONE) {
1381 			tlshdr->tls_vminor = TLS_MINOR_VER_TWO;
1382 			tlshdr->tls_type = TLS_RLTYPE_APP;
1383 			/* save the real record type for later */
1384 			m->m_epg_record_type = record_type;
1385 			m->m_epg_trail[0] = record_type;
1386 		} else {
1387 			tlshdr->tls_vminor = tls->params.tls_vminor;
1388 			tlshdr->tls_type = record_type;
1389 		}
1390 		tlshdr->tls_length = htons(m->m_len - sizeof(*tlshdr));
1391 
1392 		/*
1393 		 * Store nonces / explicit IVs after the end of the
1394 		 * TLS header.
1395 		 *
1396 		 * For GCM with TLS 1.2, an 8 byte nonce is copied
1397 		 * from the end of the IV.  The nonce is then
1398 		 * incremented for use by the next record.
1399 		 *
1400 		 * For CBC, a random nonce is inserted for TLS 1.1+.
1401 		 */
1402 		if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16 &&
1403 		    tls->params.tls_vminor == TLS_MINOR_VER_TWO) {
1404 			noncep = (uint64_t *)(tls->params.iv + 8);
1405 			be64enc(tlshdr + 1, *noncep);
1406 			(*noncep)++;
1407 		} else if (tls->params.cipher_algorithm == CRYPTO_AES_CBC &&
1408 		    tls->params.tls_vminor >= TLS_MINOR_VER_ONE)
1409 			arc4rand(tlshdr + 1, AES_BLOCK_LEN, 0);
1410 
1411 		/*
1412 		 * When using SW encryption, mark the mbuf not ready.
1413 		 * It will be marked ready via sbready() after the
1414 		 * record has been encrypted.
1415 		 *
1416 		 * When using ifnet TLS, unencrypted TLS records are
1417 		 * sent down the stack to the NIC.
1418 		 */
1419 		if (tls->mode == TCP_TLS_MODE_SW) {
1420 			m->m_flags |= M_NOTREADY;
1421 			m->m_epg_nrdy = m->m_epg_npgs;
1422 			*enq_cnt += m->m_epg_npgs;
1423 		}
1424 	}
1425 }
1426 
1427 void
1428 ktls_enqueue_to_free(struct mbuf *m)
1429 {
1430 	struct ktls_wq *wq;
1431 	bool running;
1432 
1433 	/* Mark it for freeing. */
1434 	m->m_epg_flags |= EPG_FLAG_2FREE;
1435 	wq = &ktls_wq[m->m_epg_tls->wq_index];
1436 	mtx_lock(&wq->mtx);
1437 	STAILQ_INSERT_TAIL(&wq->head, m, m_epg_stailq);
1438 	running = wq->running;
1439 	mtx_unlock(&wq->mtx);
1440 	if (!running)
1441 		wakeup(wq);
1442 }
1443 
1444 void
1445 ktls_enqueue(struct mbuf *m, struct socket *so, int page_count)
1446 {
1447 	struct ktls_wq *wq;
1448 	bool running;
1449 
1450 	KASSERT(((m->m_flags & (M_EXTPG | M_NOTREADY)) ==
1451 	    (M_EXTPG | M_NOTREADY)),
1452 	    ("ktls_enqueue: %p not unready & nomap mbuf\n", m));
1453 	KASSERT(page_count != 0, ("enqueueing TLS mbuf with zero page count"));
1454 
1455 	KASSERT(m->m_epg_tls->mode == TCP_TLS_MODE_SW, ("!SW TLS mbuf"));
1456 
1457 	m->m_epg_enc_cnt = page_count;
1458 
1459 	/*
1460 	 * Save a pointer to the socket.  The caller is responsible
1461 	 * for taking an additional reference via soref().
1462 	 */
1463 	m->m_epg_so = so;
1464 
1465 	wq = &ktls_wq[m->m_epg_tls->wq_index];
1466 	mtx_lock(&wq->mtx);
1467 	STAILQ_INSERT_TAIL(&wq->head, m, m_epg_stailq);
1468 	running = wq->running;
1469 	mtx_unlock(&wq->mtx);
1470 	if (!running)
1471 		wakeup(wq);
1472 	counter_u64_add(ktls_cnt_on, 1);
1473 }
1474 
1475 static __noinline void
1476 ktls_encrypt(struct mbuf *top)
1477 {
1478 	struct ktls_session *tls;
1479 	struct socket *so;
1480 	struct mbuf *m;
1481 	vm_paddr_t parray[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
1482 	struct iovec src_iov[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
1483 	struct iovec dst_iov[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
1484 	vm_page_t pg;
1485 	int error, i, len, npages, off, total_pages;
1486 	bool is_anon;
1487 
1488 	so = top->m_epg_so;
1489 	tls = top->m_epg_tls;
1490 	KASSERT(tls != NULL, ("tls = NULL, top = %p\n", top));
1491 	KASSERT(so != NULL, ("so = NULL, top = %p\n", top));
1492 #ifdef INVARIANTS
1493 	top->m_epg_so = NULL;
1494 #endif
1495 	total_pages = top->m_epg_enc_cnt;
1496 	npages = 0;
1497 
1498 	/*
1499 	 * Encrypt the TLS records in the chain of mbufs starting with
1500 	 * 'top'.  'total_pages' gives us a total count of pages and is
1501 	 * used to know when we have finished encrypting the TLS
1502 	 * records originally queued with 'top'.
1503 	 *
1504 	 * NB: These mbufs are queued in the socket buffer and
1505 	 * 'm_next' is traversing the mbufs in the socket buffer.  The
1506 	 * socket buffer lock is not held while traversing this chain.
1507 	 * Since the mbufs are all marked M_NOTREADY their 'm_next'
1508 	 * pointers should be stable.  However, the 'm_next' of the
1509 	 * last mbuf encrypted is not necessarily NULL.  It can point
1510 	 * to other mbufs appended while 'top' was on the TLS work
1511 	 * queue.
1512 	 *
1513 	 * Each mbuf holds an entire TLS record.
1514 	 */
1515 	error = 0;
1516 	for (m = top; npages != total_pages; m = m->m_next) {
1517 		KASSERT(m->m_epg_tls == tls,
1518 		    ("different TLS sessions in a single mbuf chain: %p vs %p",
1519 		    tls, m->m_epg_tls));
1520 		KASSERT((m->m_flags & (M_EXTPG | M_NOTREADY)) ==
1521 		    (M_EXTPG | M_NOTREADY),
1522 		    ("%p not unready & nomap mbuf (top = %p)\n", m, top));
1523 		KASSERT(npages + m->m_epg_npgs <= total_pages,
1524 		    ("page count mismatch: top %p, total_pages %d, m %p", top,
1525 		    total_pages, m));
1526 
1527 		/*
1528 		 * Generate source and destination ivoecs to pass to
1529 		 * the SW encryption backend.  For writable mbufs, the
1530 		 * destination iovec is a copy of the source and
1531 		 * encryption is done in place.  For file-backed mbufs
1532 		 * (from sendfile), anonymous wired pages are
1533 		 * allocated and assigned to the destination iovec.
1534 		 */
1535 		is_anon = (m->m_epg_flags & EPG_FLAG_ANON) != 0;
1536 
1537 		off = m->m_epg_1st_off;
1538 		for (i = 0; i < m->m_epg_npgs; i++, off = 0) {
1539 			len = m_epg_pagelen(m, i, off);
1540 			src_iov[i].iov_len = len;
1541 			src_iov[i].iov_base =
1542 			    (char *)(void *)PHYS_TO_DMAP(m->m_epg_pa[i]) +
1543 				off;
1544 
1545 			if (is_anon) {
1546 				dst_iov[i].iov_base = src_iov[i].iov_base;
1547 				dst_iov[i].iov_len = src_iov[i].iov_len;
1548 				continue;
1549 			}
1550 retry_page:
1551 			pg = vm_page_alloc(NULL, 0, VM_ALLOC_NORMAL |
1552 			    VM_ALLOC_NOOBJ | VM_ALLOC_NODUMP | VM_ALLOC_WIRED);
1553 			if (pg == NULL) {
1554 				vm_wait(NULL);
1555 				goto retry_page;
1556 			}
1557 			parray[i] = VM_PAGE_TO_PHYS(pg);
1558 			dst_iov[i].iov_base =
1559 			    (char *)(void *)PHYS_TO_DMAP(parray[i]) + off;
1560 			dst_iov[i].iov_len = len;
1561 		}
1562 
1563 		npages += i;
1564 
1565 		error = (*tls->sw_encrypt)(tls,
1566 		    (const struct tls_record_layer *)m->m_epg_hdr,
1567 		    m->m_epg_trail, src_iov, dst_iov, i, m->m_epg_seqno,
1568 		    m->m_epg_record_type);
1569 		if (error) {
1570 			counter_u64_add(ktls_offload_failed_crypto, 1);
1571 			break;
1572 		}
1573 
1574 		/*
1575 		 * For file-backed mbufs, release the file-backed
1576 		 * pages and replace them in the ext_pgs array with
1577 		 * the anonymous wired pages allocated above.
1578 		 */
1579 		if (!is_anon) {
1580 			/* Free the old pages. */
1581 			m->m_ext.ext_free(m);
1582 
1583 			/* Replace them with the new pages. */
1584 			for (i = 0; i < m->m_epg_npgs; i++)
1585 				m->m_epg_pa[i] = parray[i];
1586 
1587 			/* Use the basic free routine. */
1588 			m->m_ext.ext_free = mb_free_mext_pgs;
1589 
1590 			/* Pages are now writable. */
1591 			m->m_epg_flags |= EPG_FLAG_ANON;
1592 		}
1593 
1594 		/*
1595 		 * Drop a reference to the session now that it is no
1596 		 * longer needed.  Existing code depends on encrypted
1597 		 * records having no associated session vs
1598 		 * yet-to-be-encrypted records having an associated
1599 		 * session.
1600 		 */
1601 		m->m_epg_tls = NULL;
1602 		ktls_free(tls);
1603 	}
1604 
1605 	CURVNET_SET(so->so_vnet);
1606 	if (error == 0) {
1607 		(void)(*so->so_proto->pr_usrreqs->pru_ready)(so, top, npages);
1608 	} else {
1609 		so->so_proto->pr_usrreqs->pru_abort(so);
1610 		so->so_error = EIO;
1611 		mb_free_notready(top, total_pages);
1612 	}
1613 
1614 	SOCK_LOCK(so);
1615 	sorele(so);
1616 	CURVNET_RESTORE();
1617 }
1618 
1619 static void
1620 ktls_work_thread(void *ctx)
1621 {
1622 	struct ktls_wq *wq = ctx;
1623 	struct mbuf *m, *n;
1624 	STAILQ_HEAD(, mbuf) local_head;
1625 
1626 #if defined(__aarch64__) || defined(__amd64__) || defined(__i386__)
1627 	fpu_kern_thread(0);
1628 #endif
1629 	for (;;) {
1630 		mtx_lock(&wq->mtx);
1631 		while (STAILQ_EMPTY(&wq->head)) {
1632 			wq->running = false;
1633 			mtx_sleep(wq, &wq->mtx, 0, "-", 0);
1634 			wq->running = true;
1635 		}
1636 
1637 		STAILQ_INIT(&local_head);
1638 		STAILQ_CONCAT(&local_head, &wq->head);
1639 		mtx_unlock(&wq->mtx);
1640 
1641 		STAILQ_FOREACH_SAFE(m, &local_head, m_epg_stailq, n) {
1642 			if (m->m_epg_flags & EPG_FLAG_2FREE) {
1643 				ktls_free(m->m_epg_tls);
1644 				uma_zfree(zone_mbuf, m);
1645 			} else {
1646 				ktls_encrypt(m);
1647 				counter_u64_add(ktls_cnt_on, -1);
1648 			}
1649 		}
1650 	}
1651 }
1652