xref: /freebsd/sys/kern/uipc_ktls.c (revision e17f5b1d)
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 		zfree(tls->params.auth_key, M_KTLS);
686 		tls->params.auth_key = NULL;
687 		tls->params.auth_key_len = 0;
688 	}
689 	if (tls->params.cipher_key != NULL) {
690 		zfree(tls->params.cipher_key, M_KTLS);
691 		tls->params.cipher_key = NULL;
692 		tls->params.cipher_key_len = 0;
693 	}
694 	explicit_bzero(tls->params.iv, sizeof(tls->params.iv));
695 }
696 
697 #if defined(INET) || defined(INET6)
698 
699 #ifdef TCP_OFFLOAD
700 static int
701 ktls_try_toe(struct socket *so, struct ktls_session *tls, int direction)
702 {
703 	struct inpcb *inp;
704 	struct tcpcb *tp;
705 	int error;
706 
707 	inp = so->so_pcb;
708 	INP_WLOCK(inp);
709 	if (inp->inp_flags2 & INP_FREED) {
710 		INP_WUNLOCK(inp);
711 		return (ECONNRESET);
712 	}
713 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
714 		INP_WUNLOCK(inp);
715 		return (ECONNRESET);
716 	}
717 	if (inp->inp_socket == NULL) {
718 		INP_WUNLOCK(inp);
719 		return (ECONNRESET);
720 	}
721 	tp = intotcpcb(inp);
722 	if (tp->tod == NULL) {
723 		INP_WUNLOCK(inp);
724 		return (EOPNOTSUPP);
725 	}
726 
727 	error = tcp_offload_alloc_tls_session(tp, tls, direction);
728 	INP_WUNLOCK(inp);
729 	if (error == 0) {
730 		tls->mode = TCP_TLS_MODE_TOE;
731 		switch (tls->params.cipher_algorithm) {
732 		case CRYPTO_AES_CBC:
733 			counter_u64_add(ktls_toe_cbc, 1);
734 			break;
735 		case CRYPTO_AES_NIST_GCM_16:
736 			counter_u64_add(ktls_toe_gcm, 1);
737 			break;
738 		}
739 	}
740 	return (error);
741 }
742 #endif
743 
744 /*
745  * Common code used when first enabling ifnet TLS on a connection or
746  * when allocating a new ifnet TLS session due to a routing change.
747  * This function allocates a new TLS send tag on whatever interface
748  * the connection is currently routed over.
749  */
750 static int
751 ktls_alloc_snd_tag(struct inpcb *inp, struct ktls_session *tls, bool force,
752     struct m_snd_tag **mstp)
753 {
754 	union if_snd_tag_alloc_params params;
755 	struct ifnet *ifp;
756 	struct nhop_object *nh;
757 	struct tcpcb *tp;
758 	int error;
759 
760 	INP_RLOCK(inp);
761 	if (inp->inp_flags2 & INP_FREED) {
762 		INP_RUNLOCK(inp);
763 		return (ECONNRESET);
764 	}
765 	if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
766 		INP_RUNLOCK(inp);
767 		return (ECONNRESET);
768 	}
769 	if (inp->inp_socket == NULL) {
770 		INP_RUNLOCK(inp);
771 		return (ECONNRESET);
772 	}
773 	tp = intotcpcb(inp);
774 
775 	/*
776 	 * Check administrative controls on ifnet TLS to determine if
777 	 * ifnet TLS should be denied.
778 	 *
779 	 * - Always permit 'force' requests.
780 	 * - ktls_ifnet_permitted == 0: always deny.
781 	 */
782 	if (!force && ktls_ifnet_permitted == 0) {
783 		INP_RUNLOCK(inp);
784 		return (ENXIO);
785 	}
786 
787 	/*
788 	 * XXX: Use the cached route in the inpcb to find the
789 	 * interface.  This should perhaps instead use
790 	 * rtalloc1_fib(dst, 0, 0, fibnum).  Since KTLS is only
791 	 * enabled after a connection has completed key negotiation in
792 	 * userland, the cached route will be present in practice.
793 	 */
794 	nh = inp->inp_route.ro_nh;
795 	if (nh == NULL) {
796 		INP_RUNLOCK(inp);
797 		return (ENXIO);
798 	}
799 	ifp = nh->nh_ifp;
800 	if_ref(ifp);
801 
802 	params.hdr.type = IF_SND_TAG_TYPE_TLS;
803 	params.hdr.flowid = inp->inp_flowid;
804 	params.hdr.flowtype = inp->inp_flowtype;
805 	params.hdr.numa_domain = inp->inp_numa_domain;
806 	params.tls.inp = inp;
807 	params.tls.tls = tls;
808 	INP_RUNLOCK(inp);
809 
810 	if (ifp->if_snd_tag_alloc == NULL) {
811 		error = EOPNOTSUPP;
812 		goto out;
813 	}
814 	if ((ifp->if_capenable & IFCAP_NOMAP) == 0) {
815 		error = EOPNOTSUPP;
816 		goto out;
817 	}
818 	if (inp->inp_vflag & INP_IPV6) {
819 		if ((ifp->if_capenable & IFCAP_TXTLS6) == 0) {
820 			error = EOPNOTSUPP;
821 			goto out;
822 		}
823 	} else {
824 		if ((ifp->if_capenable & IFCAP_TXTLS4) == 0) {
825 			error = EOPNOTSUPP;
826 			goto out;
827 		}
828 	}
829 	error = ifp->if_snd_tag_alloc(ifp, &params, mstp);
830 out:
831 	if_rele(ifp);
832 	return (error);
833 }
834 
835 static int
836 ktls_try_ifnet(struct socket *so, struct ktls_session *tls, bool force)
837 {
838 	struct m_snd_tag *mst;
839 	int error;
840 
841 	error = ktls_alloc_snd_tag(so->so_pcb, tls, force, &mst);
842 	if (error == 0) {
843 		tls->mode = TCP_TLS_MODE_IFNET;
844 		tls->snd_tag = mst;
845 		switch (tls->params.cipher_algorithm) {
846 		case CRYPTO_AES_CBC:
847 			counter_u64_add(ktls_ifnet_cbc, 1);
848 			break;
849 		case CRYPTO_AES_NIST_GCM_16:
850 			counter_u64_add(ktls_ifnet_gcm, 1);
851 			break;
852 		}
853 	}
854 	return (error);
855 }
856 
857 static int
858 ktls_try_sw(struct socket *so, struct ktls_session *tls)
859 {
860 	struct rm_priotracker prio;
861 	struct ktls_crypto_backend *be;
862 
863 	/*
864 	 * Choose the best software crypto backend.  Backends are
865 	 * stored in sorted priority order (larget value == most
866 	 * important at the head of the list), so this just stops on
867 	 * the first backend that claims the session by returning
868 	 * success.
869 	 */
870 	if (ktls_allow_unload)
871 		rm_rlock(&ktls_backends_lock, &prio);
872 	LIST_FOREACH(be, &ktls_backends, next) {
873 		if (be->try(so, tls) == 0)
874 			break;
875 		KASSERT(tls->cipher == NULL,
876 		    ("ktls backend leaked a cipher pointer"));
877 	}
878 	if (be != NULL) {
879 		if (ktls_allow_unload)
880 			be->use_count++;
881 		tls->be = be;
882 	}
883 	if (ktls_allow_unload)
884 		rm_runlock(&ktls_backends_lock, &prio);
885 	if (be == NULL)
886 		return (EOPNOTSUPP);
887 	tls->mode = TCP_TLS_MODE_SW;
888 	switch (tls->params.cipher_algorithm) {
889 	case CRYPTO_AES_CBC:
890 		counter_u64_add(ktls_sw_cbc, 1);
891 		break;
892 	case CRYPTO_AES_NIST_GCM_16:
893 		counter_u64_add(ktls_sw_gcm, 1);
894 		break;
895 	}
896 	return (0);
897 }
898 
899 int
900 ktls_enable_rx(struct socket *so, struct tls_enable *en)
901 {
902 	struct ktls_session *tls;
903 	int error;
904 
905 	if (!ktls_offload_enable)
906 		return (ENOTSUP);
907 
908 	counter_u64_add(ktls_offload_enable_calls, 1);
909 
910 	/*
911 	 * This should always be true since only the TCP socket option
912 	 * invokes this function.
913 	 */
914 	if (so->so_proto->pr_protocol != IPPROTO_TCP)
915 		return (EINVAL);
916 
917 	/*
918 	 * XXX: Don't overwrite existing sessions.  We should permit
919 	 * this to support rekeying in the future.
920 	 */
921 	if (so->so_rcv.sb_tls_info != NULL)
922 		return (EALREADY);
923 
924 	if (en->cipher_algorithm == CRYPTO_AES_CBC && !ktls_cbc_enable)
925 		return (ENOTSUP);
926 
927 	error = ktls_create_session(so, en, &tls);
928 	if (error)
929 		return (error);
930 
931 	/* TLS RX offload is only supported on TOE currently. */
932 #ifdef TCP_OFFLOAD
933 	error = ktls_try_toe(so, tls, KTLS_RX);
934 #else
935 	error = EOPNOTSUPP;
936 #endif
937 
938 	if (error) {
939 		ktls_cleanup(tls);
940 		return (error);
941 	}
942 
943 	/* Mark the socket as using TLS offload. */
944 	SOCKBUF_LOCK(&so->so_rcv);
945 	so->so_rcv.sb_tls_info = tls;
946 	SOCKBUF_UNLOCK(&so->so_rcv);
947 
948 	counter_u64_add(ktls_offload_total, 1);
949 
950 	return (0);
951 }
952 
953 int
954 ktls_enable_tx(struct socket *so, struct tls_enable *en)
955 {
956 	struct ktls_session *tls;
957 	int error;
958 
959 	if (!ktls_offload_enable)
960 		return (ENOTSUP);
961 
962 	counter_u64_add(ktls_offload_enable_calls, 1);
963 
964 	/*
965 	 * This should always be true since only the TCP socket option
966 	 * invokes this function.
967 	 */
968 	if (so->so_proto->pr_protocol != IPPROTO_TCP)
969 		return (EINVAL);
970 
971 	/*
972 	 * XXX: Don't overwrite existing sessions.  We should permit
973 	 * this to support rekeying in the future.
974 	 */
975 	if (so->so_snd.sb_tls_info != NULL)
976 		return (EALREADY);
977 
978 	if (en->cipher_algorithm == CRYPTO_AES_CBC && !ktls_cbc_enable)
979 		return (ENOTSUP);
980 
981 	/* TLS requires ext pgs */
982 	if (mb_use_ext_pgs == 0)
983 		return (ENXIO);
984 
985 	error = ktls_create_session(so, en, &tls);
986 	if (error)
987 		return (error);
988 
989 	/* Prefer TOE -> ifnet TLS -> software TLS. */
990 #ifdef TCP_OFFLOAD
991 	error = ktls_try_toe(so, tls, KTLS_TX);
992 	if (error)
993 #endif
994 		error = ktls_try_ifnet(so, tls, false);
995 	if (error)
996 		error = ktls_try_sw(so, tls);
997 
998 	if (error) {
999 		ktls_cleanup(tls);
1000 		return (error);
1001 	}
1002 
1003 	error = sblock(&so->so_snd, SBL_WAIT);
1004 	if (error) {
1005 		ktls_cleanup(tls);
1006 		return (error);
1007 	}
1008 
1009 	SOCKBUF_LOCK(&so->so_snd);
1010 	so->so_snd.sb_tls_seqno = be64dec(en->rec_seq);
1011 	so->so_snd.sb_tls_info = tls;
1012 	if (tls->mode != TCP_TLS_MODE_SW)
1013 		so->so_snd.sb_flags |= SB_TLS_IFNET;
1014 	SOCKBUF_UNLOCK(&so->so_snd);
1015 	sbunlock(&so->so_snd);
1016 
1017 	counter_u64_add(ktls_offload_total, 1);
1018 
1019 	return (0);
1020 }
1021 
1022 int
1023 ktls_get_rx_mode(struct socket *so)
1024 {
1025 	struct ktls_session *tls;
1026 	struct inpcb *inp;
1027 	int mode;
1028 
1029 	inp = so->so_pcb;
1030 	INP_WLOCK_ASSERT(inp);
1031 	SOCKBUF_LOCK(&so->so_rcv);
1032 	tls = so->so_rcv.sb_tls_info;
1033 	if (tls == NULL)
1034 		mode = TCP_TLS_MODE_NONE;
1035 	else
1036 		mode = tls->mode;
1037 	SOCKBUF_UNLOCK(&so->so_rcv);
1038 	return (mode);
1039 }
1040 
1041 int
1042 ktls_get_tx_mode(struct socket *so)
1043 {
1044 	struct ktls_session *tls;
1045 	struct inpcb *inp;
1046 	int mode;
1047 
1048 	inp = so->so_pcb;
1049 	INP_WLOCK_ASSERT(inp);
1050 	SOCKBUF_LOCK(&so->so_snd);
1051 	tls = so->so_snd.sb_tls_info;
1052 	if (tls == NULL)
1053 		mode = TCP_TLS_MODE_NONE;
1054 	else
1055 		mode = tls->mode;
1056 	SOCKBUF_UNLOCK(&so->so_snd);
1057 	return (mode);
1058 }
1059 
1060 /*
1061  * Switch between SW and ifnet TLS sessions as requested.
1062  */
1063 int
1064 ktls_set_tx_mode(struct socket *so, int mode)
1065 {
1066 	struct ktls_session *tls, *tls_new;
1067 	struct inpcb *inp;
1068 	int error;
1069 
1070 	switch (mode) {
1071 	case TCP_TLS_MODE_SW:
1072 	case TCP_TLS_MODE_IFNET:
1073 		break;
1074 	default:
1075 		return (EINVAL);
1076 	}
1077 
1078 	inp = so->so_pcb;
1079 	INP_WLOCK_ASSERT(inp);
1080 	SOCKBUF_LOCK(&so->so_snd);
1081 	tls = so->so_snd.sb_tls_info;
1082 	if (tls == NULL) {
1083 		SOCKBUF_UNLOCK(&so->so_snd);
1084 		return (0);
1085 	}
1086 
1087 	if (tls->mode == mode) {
1088 		SOCKBUF_UNLOCK(&so->so_snd);
1089 		return (0);
1090 	}
1091 
1092 	tls = ktls_hold(tls);
1093 	SOCKBUF_UNLOCK(&so->so_snd);
1094 	INP_WUNLOCK(inp);
1095 
1096 	tls_new = ktls_clone_session(tls);
1097 
1098 	if (mode == TCP_TLS_MODE_IFNET)
1099 		error = ktls_try_ifnet(so, tls_new, true);
1100 	else
1101 		error = ktls_try_sw(so, tls_new);
1102 	if (error) {
1103 		counter_u64_add(ktls_switch_failed, 1);
1104 		ktls_free(tls_new);
1105 		ktls_free(tls);
1106 		INP_WLOCK(inp);
1107 		return (error);
1108 	}
1109 
1110 	error = sblock(&so->so_snd, SBL_WAIT);
1111 	if (error) {
1112 		counter_u64_add(ktls_switch_failed, 1);
1113 		ktls_free(tls_new);
1114 		ktls_free(tls);
1115 		INP_WLOCK(inp);
1116 		return (error);
1117 	}
1118 
1119 	/*
1120 	 * If we raced with another session change, keep the existing
1121 	 * session.
1122 	 */
1123 	if (tls != so->so_snd.sb_tls_info) {
1124 		counter_u64_add(ktls_switch_failed, 1);
1125 		sbunlock(&so->so_snd);
1126 		ktls_free(tls_new);
1127 		ktls_free(tls);
1128 		INP_WLOCK(inp);
1129 		return (EBUSY);
1130 	}
1131 
1132 	SOCKBUF_LOCK(&so->so_snd);
1133 	so->so_snd.sb_tls_info = tls_new;
1134 	if (tls_new->mode != TCP_TLS_MODE_SW)
1135 		so->so_snd.sb_flags |= SB_TLS_IFNET;
1136 	SOCKBUF_UNLOCK(&so->so_snd);
1137 	sbunlock(&so->so_snd);
1138 
1139 	/*
1140 	 * Drop two references on 'tls'.  The first is for the
1141 	 * ktls_hold() above.  The second drops the reference from the
1142 	 * socket buffer.
1143 	 */
1144 	KASSERT(tls->refcount >= 2, ("too few references on old session"));
1145 	ktls_free(tls);
1146 	ktls_free(tls);
1147 
1148 	if (mode == TCP_TLS_MODE_IFNET)
1149 		counter_u64_add(ktls_switch_to_ifnet, 1);
1150 	else
1151 		counter_u64_add(ktls_switch_to_sw, 1);
1152 
1153 	INP_WLOCK(inp);
1154 	return (0);
1155 }
1156 
1157 /*
1158  * Try to allocate a new TLS send tag.  This task is scheduled when
1159  * ip_output detects a route change while trying to transmit a packet
1160  * holding a TLS record.  If a new tag is allocated, replace the tag
1161  * in the TLS session.  Subsequent packets on the connection will use
1162  * the new tag.  If a new tag cannot be allocated, drop the
1163  * connection.
1164  */
1165 static void
1166 ktls_reset_send_tag(void *context, int pending)
1167 {
1168 	struct epoch_tracker et;
1169 	struct ktls_session *tls;
1170 	struct m_snd_tag *old, *new;
1171 	struct inpcb *inp;
1172 	struct tcpcb *tp;
1173 	int error;
1174 
1175 	MPASS(pending == 1);
1176 
1177 	tls = context;
1178 	inp = tls->inp;
1179 
1180 	/*
1181 	 * Free the old tag first before allocating a new one.
1182 	 * ip[6]_output_send() will treat a NULL send tag the same as
1183 	 * an ifp mismatch and drop packets until a new tag is
1184 	 * allocated.
1185 	 *
1186 	 * Write-lock the INP when changing tls->snd_tag since
1187 	 * ip[6]_output_send() holds a read-lock when reading the
1188 	 * pointer.
1189 	 */
1190 	INP_WLOCK(inp);
1191 	old = tls->snd_tag;
1192 	tls->snd_tag = NULL;
1193 	INP_WUNLOCK(inp);
1194 	if (old != NULL)
1195 		m_snd_tag_rele(old);
1196 
1197 	error = ktls_alloc_snd_tag(inp, tls, true, &new);
1198 
1199 	if (error == 0) {
1200 		INP_WLOCK(inp);
1201 		tls->snd_tag = new;
1202 		mtx_pool_lock(mtxpool_sleep, tls);
1203 		tls->reset_pending = false;
1204 		mtx_pool_unlock(mtxpool_sleep, tls);
1205 		if (!in_pcbrele_wlocked(inp))
1206 			INP_WUNLOCK(inp);
1207 
1208 		counter_u64_add(ktls_ifnet_reset, 1);
1209 
1210 		/*
1211 		 * XXX: Should we kick tcp_output explicitly now that
1212 		 * the send tag is fixed or just rely on timers?
1213 		 */
1214 	} else {
1215 		NET_EPOCH_ENTER(et);
1216 		INP_WLOCK(inp);
1217 		if (!in_pcbrele_wlocked(inp)) {
1218 			if (!(inp->inp_flags & INP_TIMEWAIT) &&
1219 			    !(inp->inp_flags & INP_DROPPED)) {
1220 				tp = intotcpcb(inp);
1221 				CURVNET_SET(tp->t_vnet);
1222 				tp = tcp_drop(tp, ECONNABORTED);
1223 				CURVNET_RESTORE();
1224 				if (tp != NULL)
1225 					INP_WUNLOCK(inp);
1226 				counter_u64_add(ktls_ifnet_reset_dropped, 1);
1227 			} else
1228 				INP_WUNLOCK(inp);
1229 		}
1230 		NET_EPOCH_EXIT(et);
1231 
1232 		counter_u64_add(ktls_ifnet_reset_failed, 1);
1233 
1234 		/*
1235 		 * Leave reset_pending true to avoid future tasks while
1236 		 * the socket goes away.
1237 		 */
1238 	}
1239 
1240 	ktls_free(tls);
1241 }
1242 
1243 int
1244 ktls_output_eagain(struct inpcb *inp, struct ktls_session *tls)
1245 {
1246 
1247 	if (inp == NULL)
1248 		return (ENOBUFS);
1249 
1250 	INP_LOCK_ASSERT(inp);
1251 
1252 	/*
1253 	 * See if we should schedule a task to update the send tag for
1254 	 * this session.
1255 	 */
1256 	mtx_pool_lock(mtxpool_sleep, tls);
1257 	if (!tls->reset_pending) {
1258 		(void) ktls_hold(tls);
1259 		in_pcbref(inp);
1260 		tls->inp = inp;
1261 		tls->reset_pending = true;
1262 		taskqueue_enqueue(taskqueue_thread, &tls->reset_tag_task);
1263 	}
1264 	mtx_pool_unlock(mtxpool_sleep, tls);
1265 	return (ENOBUFS);
1266 }
1267 #endif
1268 
1269 void
1270 ktls_destroy(struct ktls_session *tls)
1271 {
1272 	struct rm_priotracker prio;
1273 
1274 	ktls_cleanup(tls);
1275 	if (tls->be != NULL && ktls_allow_unload) {
1276 		rm_rlock(&ktls_backends_lock, &prio);
1277 		tls->be->use_count--;
1278 		rm_runlock(&ktls_backends_lock, &prio);
1279 	}
1280 	uma_zfree(ktls_session_zone, tls);
1281 }
1282 
1283 void
1284 ktls_seq(struct sockbuf *sb, struct mbuf *m)
1285 {
1286 
1287 	for (; m != NULL; m = m->m_next) {
1288 		KASSERT((m->m_flags & M_EXTPG) != 0,
1289 		    ("ktls_seq: mapped mbuf %p", m));
1290 
1291 		m->m_epg_seqno = sb->sb_tls_seqno;
1292 		sb->sb_tls_seqno++;
1293 	}
1294 }
1295 
1296 /*
1297  * Add TLS framing (headers and trailers) to a chain of mbufs.  Each
1298  * mbuf in the chain must be an unmapped mbuf.  The payload of the
1299  * mbuf must be populated with the payload of each TLS record.
1300  *
1301  * The record_type argument specifies the TLS record type used when
1302  * populating the TLS header.
1303  *
1304  * The enq_count argument on return is set to the number of pages of
1305  * payload data for this entire chain that need to be encrypted via SW
1306  * encryption.  The returned value should be passed to ktls_enqueue
1307  * when scheduling encryption of this chain of mbufs.
1308  */
1309 void
1310 ktls_frame(struct mbuf *top, struct ktls_session *tls, int *enq_cnt,
1311     uint8_t record_type)
1312 {
1313 	struct tls_record_layer *tlshdr;
1314 	struct mbuf *m;
1315 	uint64_t *noncep;
1316 	uint16_t tls_len;
1317 	int maxlen;
1318 
1319 	maxlen = tls->params.max_frame_len;
1320 	*enq_cnt = 0;
1321 	for (m = top; m != NULL; m = m->m_next) {
1322 		/*
1323 		 * All mbufs in the chain should be non-empty TLS
1324 		 * records whose payload does not exceed the maximum
1325 		 * frame length.
1326 		 */
1327 		KASSERT(m->m_len <= maxlen && m->m_len > 0,
1328 		    ("ktls_frame: m %p len %d\n", m, m->m_len));
1329 		/*
1330 		 * TLS frames require unmapped mbufs to store session
1331 		 * info.
1332 		 */
1333 		KASSERT((m->m_flags & M_EXTPG) != 0,
1334 		    ("ktls_frame: mapped mbuf %p (top = %p)\n", m, top));
1335 
1336 		tls_len = m->m_len;
1337 
1338 		/* Save a reference to the session. */
1339 		m->m_epg_tls = ktls_hold(tls);
1340 
1341 		m->m_epg_hdrlen = tls->params.tls_hlen;
1342 		m->m_epg_trllen = tls->params.tls_tlen;
1343 		if (tls->params.cipher_algorithm == CRYPTO_AES_CBC) {
1344 			int bs, delta;
1345 
1346 			/*
1347 			 * AES-CBC pads messages to a multiple of the
1348 			 * block size.  Note that the padding is
1349 			 * applied after the digest and the encryption
1350 			 * is done on the "plaintext || mac || padding".
1351 			 * At least one byte of padding is always
1352 			 * present.
1353 			 *
1354 			 * Compute the final trailer length assuming
1355 			 * at most one block of padding.
1356 			 * tls->params.sb_tls_tlen is the maximum
1357 			 * possible trailer length (padding + digest).
1358 			 * delta holds the number of excess padding
1359 			 * bytes if the maximum were used.  Those
1360 			 * extra bytes are removed.
1361 			 */
1362 			bs = tls->params.tls_bs;
1363 			delta = (tls_len + tls->params.tls_tlen) & (bs - 1);
1364 			m->m_epg_trllen -= delta;
1365 		}
1366 		m->m_len += m->m_epg_hdrlen + m->m_epg_trllen;
1367 
1368 		/* Populate the TLS header. */
1369 		tlshdr = (void *)m->m_epg_hdr;
1370 		tlshdr->tls_vmajor = tls->params.tls_vmajor;
1371 
1372 		/*
1373 		 * TLS 1.3 masquarades as TLS 1.2 with a record type
1374 		 * of TLS_RLTYPE_APP.
1375 		 */
1376 		if (tls->params.tls_vminor == TLS_MINOR_VER_THREE &&
1377 		    tls->params.tls_vmajor == TLS_MAJOR_VER_ONE) {
1378 			tlshdr->tls_vminor = TLS_MINOR_VER_TWO;
1379 			tlshdr->tls_type = TLS_RLTYPE_APP;
1380 			/* save the real record type for later */
1381 			m->m_epg_record_type = record_type;
1382 			m->m_epg_trail[0] = record_type;
1383 		} else {
1384 			tlshdr->tls_vminor = tls->params.tls_vminor;
1385 			tlshdr->tls_type = record_type;
1386 		}
1387 		tlshdr->tls_length = htons(m->m_len - sizeof(*tlshdr));
1388 
1389 		/*
1390 		 * Store nonces / explicit IVs after the end of the
1391 		 * TLS header.
1392 		 *
1393 		 * For GCM with TLS 1.2, an 8 byte nonce is copied
1394 		 * from the end of the IV.  The nonce is then
1395 		 * incremented for use by the next record.
1396 		 *
1397 		 * For CBC, a random nonce is inserted for TLS 1.1+.
1398 		 */
1399 		if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16 &&
1400 		    tls->params.tls_vminor == TLS_MINOR_VER_TWO) {
1401 			noncep = (uint64_t *)(tls->params.iv + 8);
1402 			be64enc(tlshdr + 1, *noncep);
1403 			(*noncep)++;
1404 		} else if (tls->params.cipher_algorithm == CRYPTO_AES_CBC &&
1405 		    tls->params.tls_vminor >= TLS_MINOR_VER_ONE)
1406 			arc4rand(tlshdr + 1, AES_BLOCK_LEN, 0);
1407 
1408 		/*
1409 		 * When using SW encryption, mark the mbuf not ready.
1410 		 * It will be marked ready via sbready() after the
1411 		 * record has been encrypted.
1412 		 *
1413 		 * When using ifnet TLS, unencrypted TLS records are
1414 		 * sent down the stack to the NIC.
1415 		 */
1416 		if (tls->mode == TCP_TLS_MODE_SW) {
1417 			m->m_flags |= M_NOTREADY;
1418 			m->m_epg_nrdy = m->m_epg_npgs;
1419 			*enq_cnt += m->m_epg_npgs;
1420 		}
1421 	}
1422 }
1423 
1424 void
1425 ktls_enqueue_to_free(struct mbuf *m)
1426 {
1427 	struct ktls_wq *wq;
1428 	bool running;
1429 
1430 	/* Mark it for freeing. */
1431 	m->m_epg_flags |= EPG_FLAG_2FREE;
1432 	wq = &ktls_wq[m->m_epg_tls->wq_index];
1433 	mtx_lock(&wq->mtx);
1434 	STAILQ_INSERT_TAIL(&wq->head, m, m_epg_stailq);
1435 	running = wq->running;
1436 	mtx_unlock(&wq->mtx);
1437 	if (!running)
1438 		wakeup(wq);
1439 }
1440 
1441 void
1442 ktls_enqueue(struct mbuf *m, struct socket *so, int page_count)
1443 {
1444 	struct ktls_wq *wq;
1445 	bool running;
1446 
1447 	KASSERT(((m->m_flags & (M_EXTPG | M_NOTREADY)) ==
1448 	    (M_EXTPG | M_NOTREADY)),
1449 	    ("ktls_enqueue: %p not unready & nomap mbuf\n", m));
1450 	KASSERT(page_count != 0, ("enqueueing TLS mbuf with zero page count"));
1451 
1452 	KASSERT(m->m_epg_tls->mode == TCP_TLS_MODE_SW, ("!SW TLS mbuf"));
1453 
1454 	m->m_epg_enc_cnt = page_count;
1455 
1456 	/*
1457 	 * Save a pointer to the socket.  The caller is responsible
1458 	 * for taking an additional reference via soref().
1459 	 */
1460 	m->m_epg_so = so;
1461 
1462 	wq = &ktls_wq[m->m_epg_tls->wq_index];
1463 	mtx_lock(&wq->mtx);
1464 	STAILQ_INSERT_TAIL(&wq->head, m, m_epg_stailq);
1465 	running = wq->running;
1466 	mtx_unlock(&wq->mtx);
1467 	if (!running)
1468 		wakeup(wq);
1469 	counter_u64_add(ktls_cnt_on, 1);
1470 }
1471 
1472 static __noinline void
1473 ktls_encrypt(struct mbuf *top)
1474 {
1475 	struct ktls_session *tls;
1476 	struct socket *so;
1477 	struct mbuf *m;
1478 	vm_paddr_t parray[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
1479 	struct iovec src_iov[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
1480 	struct iovec dst_iov[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
1481 	vm_page_t pg;
1482 	int error, i, len, npages, off, total_pages;
1483 	bool is_anon;
1484 
1485 	so = top->m_epg_so;
1486 	tls = top->m_epg_tls;
1487 	KASSERT(tls != NULL, ("tls = NULL, top = %p\n", top));
1488 	KASSERT(so != NULL, ("so = NULL, top = %p\n", top));
1489 #ifdef INVARIANTS
1490 	top->m_epg_so = NULL;
1491 #endif
1492 	total_pages = top->m_epg_enc_cnt;
1493 	npages = 0;
1494 
1495 	/*
1496 	 * Encrypt the TLS records in the chain of mbufs starting with
1497 	 * 'top'.  'total_pages' gives us a total count of pages and is
1498 	 * used to know when we have finished encrypting the TLS
1499 	 * records originally queued with 'top'.
1500 	 *
1501 	 * NB: These mbufs are queued in the socket buffer and
1502 	 * 'm_next' is traversing the mbufs in the socket buffer.  The
1503 	 * socket buffer lock is not held while traversing this chain.
1504 	 * Since the mbufs are all marked M_NOTREADY their 'm_next'
1505 	 * pointers should be stable.  However, the 'm_next' of the
1506 	 * last mbuf encrypted is not necessarily NULL.  It can point
1507 	 * to other mbufs appended while 'top' was on the TLS work
1508 	 * queue.
1509 	 *
1510 	 * Each mbuf holds an entire TLS record.
1511 	 */
1512 	error = 0;
1513 	for (m = top; npages != total_pages; m = m->m_next) {
1514 		KASSERT(m->m_epg_tls == tls,
1515 		    ("different TLS sessions in a single mbuf chain: %p vs %p",
1516 		    tls, m->m_epg_tls));
1517 		KASSERT((m->m_flags & (M_EXTPG | M_NOTREADY)) ==
1518 		    (M_EXTPG | M_NOTREADY),
1519 		    ("%p not unready & nomap mbuf (top = %p)\n", m, top));
1520 		KASSERT(npages + m->m_epg_npgs <= total_pages,
1521 		    ("page count mismatch: top %p, total_pages %d, m %p", top,
1522 		    total_pages, m));
1523 
1524 		/*
1525 		 * Generate source and destination ivoecs to pass to
1526 		 * the SW encryption backend.  For writable mbufs, the
1527 		 * destination iovec is a copy of the source and
1528 		 * encryption is done in place.  For file-backed mbufs
1529 		 * (from sendfile), anonymous wired pages are
1530 		 * allocated and assigned to the destination iovec.
1531 		 */
1532 		is_anon = (m->m_epg_flags & EPG_FLAG_ANON) != 0;
1533 
1534 		off = m->m_epg_1st_off;
1535 		for (i = 0; i < m->m_epg_npgs; i++, off = 0) {
1536 			len = m_epg_pagelen(m, i, off);
1537 			src_iov[i].iov_len = len;
1538 			src_iov[i].iov_base =
1539 			    (char *)(void *)PHYS_TO_DMAP(m->m_epg_pa[i]) +
1540 				off;
1541 
1542 			if (is_anon) {
1543 				dst_iov[i].iov_base = src_iov[i].iov_base;
1544 				dst_iov[i].iov_len = src_iov[i].iov_len;
1545 				continue;
1546 			}
1547 retry_page:
1548 			pg = vm_page_alloc(NULL, 0, VM_ALLOC_NORMAL |
1549 			    VM_ALLOC_NOOBJ | VM_ALLOC_NODUMP | VM_ALLOC_WIRED);
1550 			if (pg == NULL) {
1551 				vm_wait(NULL);
1552 				goto retry_page;
1553 			}
1554 			parray[i] = VM_PAGE_TO_PHYS(pg);
1555 			dst_iov[i].iov_base =
1556 			    (char *)(void *)PHYS_TO_DMAP(parray[i]) + off;
1557 			dst_iov[i].iov_len = len;
1558 		}
1559 
1560 		npages += i;
1561 
1562 		error = (*tls->sw_encrypt)(tls,
1563 		    (const struct tls_record_layer *)m->m_epg_hdr,
1564 		    m->m_epg_trail, src_iov, dst_iov, i, m->m_epg_seqno,
1565 		    m->m_epg_record_type);
1566 		if (error) {
1567 			counter_u64_add(ktls_offload_failed_crypto, 1);
1568 			break;
1569 		}
1570 
1571 		/*
1572 		 * For file-backed mbufs, release the file-backed
1573 		 * pages and replace them in the ext_pgs array with
1574 		 * the anonymous wired pages allocated above.
1575 		 */
1576 		if (!is_anon) {
1577 			/* Free the old pages. */
1578 			m->m_ext.ext_free(m);
1579 
1580 			/* Replace them with the new pages. */
1581 			for (i = 0; i < m->m_epg_npgs; i++)
1582 				m->m_epg_pa[i] = parray[i];
1583 
1584 			/* Use the basic free routine. */
1585 			m->m_ext.ext_free = mb_free_mext_pgs;
1586 
1587 			/* Pages are now writable. */
1588 			m->m_epg_flags |= EPG_FLAG_ANON;
1589 		}
1590 
1591 		/*
1592 		 * Drop a reference to the session now that it is no
1593 		 * longer needed.  Existing code depends on encrypted
1594 		 * records having no associated session vs
1595 		 * yet-to-be-encrypted records having an associated
1596 		 * session.
1597 		 */
1598 		m->m_epg_tls = NULL;
1599 		ktls_free(tls);
1600 	}
1601 
1602 	CURVNET_SET(so->so_vnet);
1603 	if (error == 0) {
1604 		(void)(*so->so_proto->pr_usrreqs->pru_ready)(so, top, npages);
1605 	} else {
1606 		so->so_proto->pr_usrreqs->pru_abort(so);
1607 		so->so_error = EIO;
1608 		mb_free_notready(top, total_pages);
1609 	}
1610 
1611 	SOCK_LOCK(so);
1612 	sorele(so);
1613 	CURVNET_RESTORE();
1614 }
1615 
1616 static void
1617 ktls_work_thread(void *ctx)
1618 {
1619 	struct ktls_wq *wq = ctx;
1620 	struct mbuf *m, *n;
1621 	STAILQ_HEAD(, mbuf) local_head;
1622 
1623 #if defined(__aarch64__) || defined(__amd64__) || defined(__i386__)
1624 	fpu_kern_thread(0);
1625 #endif
1626 	for (;;) {
1627 		mtx_lock(&wq->mtx);
1628 		while (STAILQ_EMPTY(&wq->head)) {
1629 			wq->running = false;
1630 			mtx_sleep(wq, &wq->mtx, 0, "-", 0);
1631 			wq->running = true;
1632 		}
1633 
1634 		STAILQ_INIT(&local_head);
1635 		STAILQ_CONCAT(&local_head, &wq->head);
1636 		mtx_unlock(&wq->mtx);
1637 
1638 		STAILQ_FOREACH_SAFE(m, &local_head, m_epg_stailq, n) {
1639 			if (m->m_epg_flags & EPG_FLAG_2FREE) {
1640 				ktls_free(m->m_epg_tls);
1641 				uma_zfree(zone_mbuf, m);
1642 			} else {
1643 				ktls_encrypt(m);
1644 				counter_u64_add(ktls_cnt_on, -1);
1645 			}
1646 		}
1647 	}
1648 }
1649