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 #include "opt_inet.h"
30 #include "opt_inet6.h"
31 #include "opt_rss.h"
32
33 #include <sys/param.h>
34 #include <sys/kernel.h>
35 #include <sys/domainset.h>
36 #include <sys/ktls.h>
37 #include <sys/lock.h>
38 #include <sys/mbuf.h>
39 #include <sys/mutex.h>
40 #include <sys/rmlock.h>
41 #include <sys/proc.h>
42 #include <sys/protosw.h>
43 #include <sys/refcount.h>
44 #include <sys/smp.h>
45 #include <sys/socket.h>
46 #include <sys/socketvar.h>
47 #include <sys/sysctl.h>
48 #include <sys/taskqueue.h>
49 #include <sys/kthread.h>
50 #include <sys/uio.h>
51 #include <sys/vmmeter.h>
52 #if defined(__aarch64__) || defined(__amd64__) || defined(__i386__)
53 #include <machine/pcb.h>
54 #endif
55 #include <machine/vmparam.h>
56 #include <net/if.h>
57 #include <net/if_var.h>
58 #ifdef RSS
59 #include <net/netisr.h>
60 #include <net/rss_config.h>
61 #endif
62 #include <net/route.h>
63 #include <net/route/nhop.h>
64 #if defined(INET) || defined(INET6)
65 #include <netinet/in.h>
66 #include <netinet/in_pcb.h>
67 #endif
68 #include <netinet/tcp_var.h>
69 #ifdef TCP_OFFLOAD
70 #include <netinet/tcp_offload.h>
71 #endif
72 #include <opencrypto/xform.h>
73 #include <vm/uma_dbg.h>
74 #include <vm/vm.h>
75 #include <vm/vm_pageout.h>
76 #include <vm/vm_page.h>
77
78 struct ktls_wq {
79 struct mtx mtx;
80 STAILQ_HEAD(, mbuf) m_head;
81 STAILQ_HEAD(, socket) so_head;
82 bool running;
83 } __aligned(CACHE_LINE_SIZE);
84
85 struct ktls_domain_info {
86 int count;
87 int cpu[MAXCPU];
88 };
89
90 struct ktls_domain_info ktls_domains[MAXMEMDOM];
91 static struct ktls_wq *ktls_wq;
92 static struct proc *ktls_proc;
93 LIST_HEAD(, ktls_crypto_backend) ktls_backends;
94 static struct rmlock ktls_backends_lock;
95 static uma_zone_t ktls_session_zone;
96 static uint16_t ktls_cpuid_lookup[MAXCPU];
97
98 SYSCTL_NODE(_kern_ipc, OID_AUTO, tls, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
99 "Kernel TLS offload");
100 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, stats, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
101 "Kernel TLS offload stats");
102
103 static int ktls_allow_unload;
104 SYSCTL_INT(_kern_ipc_tls, OID_AUTO, allow_unload, CTLFLAG_RDTUN,
105 &ktls_allow_unload, 0, "Allow software crypto modules to unload");
106
107 #ifdef RSS
108 static int ktls_bind_threads = 1;
109 #else
110 static int ktls_bind_threads;
111 #endif
112 SYSCTL_INT(_kern_ipc_tls, OID_AUTO, bind_threads, CTLFLAG_RDTUN,
113 &ktls_bind_threads, 0,
114 "Bind crypto threads to cores (1) or cores and domains (2) at boot");
115
116 static u_int ktls_maxlen = 16384;
117 SYSCTL_UINT(_kern_ipc_tls, OID_AUTO, maxlen, CTLFLAG_RWTUN,
118 &ktls_maxlen, 0, "Maximum TLS record size");
119
120 static int ktls_number_threads;
121 SYSCTL_INT(_kern_ipc_tls_stats, OID_AUTO, threads, CTLFLAG_RD,
122 &ktls_number_threads, 0,
123 "Number of TLS threads in thread-pool");
124
125 static bool ktls_offload_enable;
126 SYSCTL_BOOL(_kern_ipc_tls, OID_AUTO, enable, CTLFLAG_RWTUN,
127 &ktls_offload_enable, 0,
128 "Enable support for kernel TLS offload");
129
130 static bool ktls_cbc_enable = true;
131 SYSCTL_BOOL(_kern_ipc_tls, OID_AUTO, cbc_enable, CTLFLAG_RWTUN,
132 &ktls_cbc_enable, 1,
133 "Enable Support of AES-CBC crypto for kernel TLS");
134
135 static COUNTER_U64_DEFINE_EARLY(ktls_tasks_active);
136 SYSCTL_COUNTER_U64(_kern_ipc_tls, OID_AUTO, tasks_active, CTLFLAG_RD,
137 &ktls_tasks_active, "Number of active tasks");
138
139 static COUNTER_U64_DEFINE_EARLY(ktls_cnt_tx_pending);
140 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, sw_tx_pending, CTLFLAG_RD,
141 &ktls_cnt_tx_pending,
142 "Number of TLS 1.0 records waiting for earlier TLS records");
143
144 static COUNTER_U64_DEFINE_EARLY(ktls_cnt_tx_queued);
145 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, sw_tx_inqueue, CTLFLAG_RD,
146 &ktls_cnt_tx_queued,
147 "Number of TLS records in queue to tasks for SW encryption");
148
149 static COUNTER_U64_DEFINE_EARLY(ktls_cnt_rx_queued);
150 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, sw_rx_inqueue, CTLFLAG_RD,
151 &ktls_cnt_rx_queued,
152 "Number of TLS sockets in queue to tasks for SW decryption");
153
154 static COUNTER_U64_DEFINE_EARLY(ktls_offload_total);
155 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, offload_total,
156 CTLFLAG_RD, &ktls_offload_total,
157 "Total successful TLS setups (parameters set)");
158
159 static COUNTER_U64_DEFINE_EARLY(ktls_offload_enable_calls);
160 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, enable_calls,
161 CTLFLAG_RD, &ktls_offload_enable_calls,
162 "Total number of TLS enable calls made");
163
164 static COUNTER_U64_DEFINE_EARLY(ktls_offload_active);
165 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, active, CTLFLAG_RD,
166 &ktls_offload_active, "Total Active TLS sessions");
167
168 static COUNTER_U64_DEFINE_EARLY(ktls_offload_corrupted_records);
169 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, corrupted_records, CTLFLAG_RD,
170 &ktls_offload_corrupted_records, "Total corrupted TLS records received");
171
172 static COUNTER_U64_DEFINE_EARLY(ktls_offload_failed_crypto);
173 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, failed_crypto, CTLFLAG_RD,
174 &ktls_offload_failed_crypto, "Total TLS crypto failures");
175
176 static COUNTER_U64_DEFINE_EARLY(ktls_switch_to_ifnet);
177 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_to_ifnet, CTLFLAG_RD,
178 &ktls_switch_to_ifnet, "TLS sessions switched from SW to ifnet");
179
180 static COUNTER_U64_DEFINE_EARLY(ktls_switch_to_sw);
181 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_to_sw, CTLFLAG_RD,
182 &ktls_switch_to_sw, "TLS sessions switched from ifnet to SW");
183
184 static COUNTER_U64_DEFINE_EARLY(ktls_switch_failed);
185 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_failed, CTLFLAG_RD,
186 &ktls_switch_failed, "TLS sessions unable to switch between SW and ifnet");
187
188 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, sw, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
189 "Software TLS session stats");
190 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, ifnet, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
191 "Hardware (ifnet) TLS session stats");
192 #ifdef TCP_OFFLOAD
193 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, toe, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
194 "TOE TLS session stats");
195 #endif
196
197 static COUNTER_U64_DEFINE_EARLY(ktls_sw_cbc);
198 SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, cbc, CTLFLAG_RD, &ktls_sw_cbc,
199 "Active number of software TLS sessions using AES-CBC");
200
201 static COUNTER_U64_DEFINE_EARLY(ktls_sw_gcm);
202 SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, gcm, CTLFLAG_RD, &ktls_sw_gcm,
203 "Active number of software TLS sessions using AES-GCM");
204
205 static COUNTER_U64_DEFINE_EARLY(ktls_sw_chacha20);
206 SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, chacha20, CTLFLAG_RD,
207 &ktls_sw_chacha20,
208 "Active number of software TLS sessions using Chacha20-Poly1305");
209
210 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_cbc);
211 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, cbc, CTLFLAG_RD,
212 &ktls_ifnet_cbc,
213 "Active number of ifnet TLS sessions using AES-CBC");
214
215 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_gcm);
216 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, gcm, CTLFLAG_RD,
217 &ktls_ifnet_gcm,
218 "Active number of ifnet TLS sessions using AES-GCM");
219
220 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_chacha20);
221 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, chacha20, CTLFLAG_RD,
222 &ktls_ifnet_chacha20,
223 "Active number of ifnet TLS sessions using Chacha20-Poly1305");
224
225 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_reset);
226 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset, CTLFLAG_RD,
227 &ktls_ifnet_reset, "TLS sessions updated to a new ifnet send tag");
228
229 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_reset_dropped);
230 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset_dropped, CTLFLAG_RD,
231 &ktls_ifnet_reset_dropped,
232 "TLS sessions dropped after failing to update ifnet send tag");
233
234 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_reset_failed);
235 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset_failed, CTLFLAG_RD,
236 &ktls_ifnet_reset_failed,
237 "TLS sessions that failed to allocate a new ifnet send tag");
238
239 static int ktls_ifnet_permitted;
240 SYSCTL_UINT(_kern_ipc_tls_ifnet, OID_AUTO, permitted, CTLFLAG_RWTUN,
241 &ktls_ifnet_permitted, 1,
242 "Whether to permit hardware (ifnet) TLS sessions");
243
244 #ifdef TCP_OFFLOAD
245 static COUNTER_U64_DEFINE_EARLY(ktls_toe_cbc);
246 SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, cbc, CTLFLAG_RD,
247 &ktls_toe_cbc,
248 "Active number of TOE TLS sessions using AES-CBC");
249
250 static COUNTER_U64_DEFINE_EARLY(ktls_toe_gcm);
251 SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, gcm, CTLFLAG_RD,
252 &ktls_toe_gcm,
253 "Active number of TOE TLS sessions using AES-GCM");
254
255 static COUNTER_U64_DEFINE_EARLY(ktls_toe_chacha20);
256 SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, chacha20, CTLFLAG_RD,
257 &ktls_toe_chacha20,
258 "Active number of TOE TLS sessions using Chacha20-Poly1305");
259 #endif
260
261 static MALLOC_DEFINE(M_KTLS, "ktls", "Kernel TLS");
262
263 static void ktls_cleanup(struct ktls_session *tls);
264 #if defined(INET) || defined(INET6)
265 static void ktls_reset_send_tag(void *context, int pending);
266 #endif
267 static void ktls_work_thread(void *ctx);
268
269 int
ktls_crypto_backend_register(struct ktls_crypto_backend * be)270 ktls_crypto_backend_register(struct ktls_crypto_backend *be)
271 {
272 struct ktls_crypto_backend *curr_be, *tmp;
273
274 if (be->api_version != KTLS_API_VERSION) {
275 printf("KTLS: API version mismatch (%d vs %d) for %s\n",
276 be->api_version, KTLS_API_VERSION,
277 be->name);
278 return (EINVAL);
279 }
280
281 rm_wlock(&ktls_backends_lock);
282 printf("KTLS: Registering crypto method %s with prio %d\n",
283 be->name, be->prio);
284 if (LIST_EMPTY(&ktls_backends)) {
285 LIST_INSERT_HEAD(&ktls_backends, be, next);
286 } else {
287 LIST_FOREACH_SAFE(curr_be, &ktls_backends, next, tmp) {
288 if (curr_be->prio < be->prio) {
289 LIST_INSERT_BEFORE(curr_be, be, next);
290 break;
291 }
292 if (LIST_NEXT(curr_be, next) == NULL) {
293 LIST_INSERT_AFTER(curr_be, be, next);
294 break;
295 }
296 }
297 }
298 rm_wunlock(&ktls_backends_lock);
299 return (0);
300 }
301
302 int
ktls_crypto_backend_deregister(struct ktls_crypto_backend * be)303 ktls_crypto_backend_deregister(struct ktls_crypto_backend *be)
304 {
305 struct ktls_crypto_backend *tmp;
306
307 /*
308 * Don't error if the backend isn't registered. This permits
309 * MOD_UNLOAD handlers to use this function unconditionally.
310 */
311 rm_wlock(&ktls_backends_lock);
312 LIST_FOREACH(tmp, &ktls_backends, next) {
313 if (tmp == be)
314 break;
315 }
316 if (tmp == NULL) {
317 rm_wunlock(&ktls_backends_lock);
318 return (0);
319 }
320
321 if (!ktls_allow_unload) {
322 rm_wunlock(&ktls_backends_lock);
323 printf(
324 "KTLS: Deregistering crypto method %s is not supported\n",
325 be->name);
326 return (EBUSY);
327 }
328
329 if (be->use_count) {
330 rm_wunlock(&ktls_backends_lock);
331 return (EBUSY);
332 }
333
334 LIST_REMOVE(be, next);
335 rm_wunlock(&ktls_backends_lock);
336 return (0);
337 }
338
339 #if defined(INET) || defined(INET6)
340 static u_int
ktls_get_cpu(struct socket * so)341 ktls_get_cpu(struct socket *so)
342 {
343 struct inpcb *inp;
344 #ifdef NUMA
345 struct ktls_domain_info *di;
346 #endif
347 u_int cpuid;
348
349 inp = sotoinpcb(so);
350 #ifdef RSS
351 cpuid = rss_hash2cpuid(inp->inp_flowid, inp->inp_flowtype);
352 if (cpuid != NETISR_CPUID_NONE)
353 return (cpuid);
354 #endif
355 /*
356 * Just use the flowid to shard connections in a repeatable
357 * fashion. Note that some crypto backends rely on the
358 * serialization provided by having the same connection use
359 * the same queue.
360 */
361 #ifdef NUMA
362 if (ktls_bind_threads > 1 && inp->inp_numa_domain != M_NODOM) {
363 di = &ktls_domains[inp->inp_numa_domain];
364 cpuid = di->cpu[inp->inp_flowid % di->count];
365 } else
366 #endif
367 cpuid = ktls_cpuid_lookup[inp->inp_flowid % ktls_number_threads];
368 return (cpuid);
369 }
370 #endif
371
372 static void
ktls_init(void * dummy __unused)373 ktls_init(void *dummy __unused)
374 {
375 struct thread *td;
376 struct pcpu *pc;
377 cpuset_t mask;
378 int count, domain, error, i;
379
380 rm_init(&ktls_backends_lock, "ktls backends");
381 LIST_INIT(&ktls_backends);
382
383 ktls_wq = malloc(sizeof(*ktls_wq) * (mp_maxid + 1), M_KTLS,
384 M_WAITOK | M_ZERO);
385
386 ktls_session_zone = uma_zcreate("ktls_session",
387 sizeof(struct ktls_session),
388 NULL, NULL, NULL, NULL,
389 UMA_ALIGN_CACHE, 0);
390
391 /*
392 * Initialize the workqueues to run the TLS work. We create a
393 * work queue for each CPU.
394 */
395 CPU_FOREACH(i) {
396 STAILQ_INIT(&ktls_wq[i].m_head);
397 STAILQ_INIT(&ktls_wq[i].so_head);
398 mtx_init(&ktls_wq[i].mtx, "ktls work queue", NULL, MTX_DEF);
399 error = kproc_kthread_add(ktls_work_thread, &ktls_wq[i],
400 &ktls_proc, &td, 0, 0, "KTLS", "thr_%d", i);
401 if (error)
402 panic("Can't add KTLS thread %d error %d", i, error);
403
404 /*
405 * Bind threads to cores. If ktls_bind_threads is >
406 * 1, then we bind to the NUMA domain.
407 */
408 if (ktls_bind_threads) {
409 if (ktls_bind_threads > 1) {
410 pc = pcpu_find(i);
411 domain = pc->pc_domain;
412 CPU_COPY(&cpuset_domain[domain], &mask);
413 count = ktls_domains[domain].count;
414 ktls_domains[domain].cpu[count] = i;
415 ktls_domains[domain].count++;
416 } else {
417 CPU_SETOF(i, &mask);
418 }
419 error = cpuset_setthread(td->td_tid, &mask);
420 if (error)
421 panic(
422 "Unable to bind KTLS thread for CPU %d error %d",
423 i, error);
424 }
425 ktls_cpuid_lookup[ktls_number_threads] = i;
426 ktls_number_threads++;
427 }
428
429 /*
430 * If we somehow have an empty domain, fall back to choosing
431 * among all KTLS threads.
432 */
433 if (ktls_bind_threads > 1) {
434 for (i = 0; i < vm_ndomains; i++) {
435 if (ktls_domains[i].count == 0) {
436 ktls_bind_threads = 1;
437 break;
438 }
439 }
440 }
441
442 if (bootverbose)
443 printf("KTLS: Initialized %d threads\n", ktls_number_threads);
444 }
445 SYSINIT(ktls, SI_SUB_SMP + 1, SI_ORDER_ANY, ktls_init, NULL);
446
447 #if defined(INET) || defined(INET6)
448 static int
ktls_create_session(struct socket * so,struct tls_enable * en,struct ktls_session ** tlsp)449 ktls_create_session(struct socket *so, struct tls_enable *en,
450 struct ktls_session **tlsp)
451 {
452 struct ktls_session *tls;
453 int error;
454
455 /* Only TLS 1.0 - 1.3 are supported. */
456 if (en->tls_vmajor != TLS_MAJOR_VER_ONE)
457 return (EINVAL);
458 if (en->tls_vminor < TLS_MINOR_VER_ZERO ||
459 en->tls_vminor > TLS_MINOR_VER_THREE)
460 return (EINVAL);
461
462 if (en->auth_key_len < 0 || en->auth_key_len > TLS_MAX_PARAM_SIZE)
463 return (EINVAL);
464 if (en->cipher_key_len < 0 || en->cipher_key_len > TLS_MAX_PARAM_SIZE)
465 return (EINVAL);
466 if (en->iv_len < 0 || en->iv_len > sizeof(tls->params.iv))
467 return (EINVAL);
468
469 /* All supported algorithms require a cipher key. */
470 if (en->cipher_key_len == 0)
471 return (EINVAL);
472
473 /* No flags are currently supported. */
474 if (en->flags != 0)
475 return (EINVAL);
476
477 /* Common checks for supported algorithms. */
478 switch (en->cipher_algorithm) {
479 case CRYPTO_AES_NIST_GCM_16:
480 /*
481 * auth_algorithm isn't used, but permit GMAC values
482 * for compatibility.
483 */
484 switch (en->auth_algorithm) {
485 case 0:
486 #ifdef COMPAT_FREEBSD12
487 /* XXX: Really 13.0-current COMPAT. */
488 case CRYPTO_AES_128_NIST_GMAC:
489 case CRYPTO_AES_192_NIST_GMAC:
490 case CRYPTO_AES_256_NIST_GMAC:
491 #endif
492 break;
493 default:
494 return (EINVAL);
495 }
496 if (en->auth_key_len != 0)
497 return (EINVAL);
498 switch (en->tls_vminor) {
499 case TLS_MINOR_VER_TWO:
500 if (en->iv_len != TLS_AEAD_GCM_LEN)
501 return (EINVAL);
502 break;
503 case TLS_MINOR_VER_THREE:
504 if (en->iv_len != TLS_1_3_GCM_IV_LEN)
505 return (EINVAL);
506 break;
507 default:
508 return (EINVAL);
509 }
510 break;
511 case CRYPTO_AES_CBC:
512 switch (en->auth_algorithm) {
513 case CRYPTO_SHA1_HMAC:
514 break;
515 case CRYPTO_SHA2_256_HMAC:
516 case CRYPTO_SHA2_384_HMAC:
517 if (en->tls_vminor != TLS_MINOR_VER_TWO)
518 return (EINVAL);
519 break;
520 default:
521 return (EINVAL);
522 }
523 if (en->auth_key_len == 0)
524 return (EINVAL);
525
526 /*
527 * TLS 1.0 requires an implicit IV. TLS 1.1 and 1.2
528 * use explicit IVs.
529 */
530 switch (en->tls_vminor) {
531 case TLS_MINOR_VER_ZERO:
532 if (en->iv_len != TLS_CBC_IMPLICIT_IV_LEN)
533 return (EINVAL);
534 break;
535 case TLS_MINOR_VER_ONE:
536 case TLS_MINOR_VER_TWO:
537 /* Ignore any supplied IV. */
538 en->iv_len = 0;
539 break;
540 default:
541 return (EINVAL);
542 }
543 break;
544 case CRYPTO_CHACHA20_POLY1305:
545 if (en->auth_algorithm != 0 || en->auth_key_len != 0)
546 return (EINVAL);
547 if (en->tls_vminor != TLS_MINOR_VER_TWO &&
548 en->tls_vminor != TLS_MINOR_VER_THREE)
549 return (EINVAL);
550 if (en->iv_len != TLS_CHACHA20_IV_LEN)
551 return (EINVAL);
552 break;
553 default:
554 return (EINVAL);
555 }
556
557 tls = uma_zalloc(ktls_session_zone, M_WAITOK | M_ZERO);
558
559 counter_u64_add(ktls_offload_active, 1);
560
561 refcount_init(&tls->refcount, 1);
562 TASK_INIT(&tls->reset_tag_task, 0, ktls_reset_send_tag, tls);
563
564 tls->wq_index = ktls_get_cpu(so);
565
566 tls->params.cipher_algorithm = en->cipher_algorithm;
567 tls->params.auth_algorithm = en->auth_algorithm;
568 tls->params.tls_vmajor = en->tls_vmajor;
569 tls->params.tls_vminor = en->tls_vminor;
570 tls->params.flags = en->flags;
571 tls->params.max_frame_len = min(TLS_MAX_MSG_SIZE_V10_2, ktls_maxlen);
572
573 /* Set the header and trailer lengths. */
574 tls->params.tls_hlen = sizeof(struct tls_record_layer);
575 switch (en->cipher_algorithm) {
576 case CRYPTO_AES_NIST_GCM_16:
577 /*
578 * TLS 1.2 uses a 4 byte implicit IV with an explicit 8 byte
579 * nonce. TLS 1.3 uses a 12 byte implicit IV.
580 */
581 if (en->tls_vminor < TLS_MINOR_VER_THREE)
582 tls->params.tls_hlen += sizeof(uint64_t);
583 tls->params.tls_tlen = AES_GMAC_HASH_LEN;
584 tls->params.tls_bs = 1;
585 break;
586 case CRYPTO_AES_CBC:
587 switch (en->auth_algorithm) {
588 case CRYPTO_SHA1_HMAC:
589 if (en->tls_vminor == TLS_MINOR_VER_ZERO) {
590 /* Implicit IV, no nonce. */
591 tls->sequential_records = true;
592 tls->next_seqno = be64dec(en->rec_seq);
593 STAILQ_INIT(&tls->pending_records);
594 } else {
595 tls->params.tls_hlen += AES_BLOCK_LEN;
596 }
597 tls->params.tls_tlen = AES_BLOCK_LEN +
598 SHA1_HASH_LEN;
599 break;
600 case CRYPTO_SHA2_256_HMAC:
601 tls->params.tls_hlen += AES_BLOCK_LEN;
602 tls->params.tls_tlen = AES_BLOCK_LEN +
603 SHA2_256_HASH_LEN;
604 break;
605 case CRYPTO_SHA2_384_HMAC:
606 tls->params.tls_hlen += AES_BLOCK_LEN;
607 tls->params.tls_tlen = AES_BLOCK_LEN +
608 SHA2_384_HASH_LEN;
609 break;
610 default:
611 panic("invalid hmac");
612 }
613 tls->params.tls_bs = AES_BLOCK_LEN;
614 break;
615 case CRYPTO_CHACHA20_POLY1305:
616 /*
617 * Chacha20 uses a 12 byte implicit IV.
618 */
619 tls->params.tls_tlen = POLY1305_HASH_LEN;
620 tls->params.tls_bs = 1;
621 break;
622 default:
623 panic("invalid cipher");
624 }
625
626 /*
627 * TLS 1.3 includes optional padding which we do not support,
628 * and also puts the "real" record type at the end of the
629 * encrypted data.
630 */
631 if (en->tls_vminor == TLS_MINOR_VER_THREE)
632 tls->params.tls_tlen += sizeof(uint8_t);
633
634 KASSERT(tls->params.tls_hlen <= MBUF_PEXT_HDR_LEN,
635 ("TLS header length too long: %d", tls->params.tls_hlen));
636 KASSERT(tls->params.tls_tlen <= MBUF_PEXT_TRAIL_LEN,
637 ("TLS trailer length too long: %d", tls->params.tls_tlen));
638
639 if (en->auth_key_len != 0) {
640 tls->params.auth_key_len = en->auth_key_len;
641 tls->params.auth_key = malloc(en->auth_key_len, M_KTLS,
642 M_WAITOK);
643 error = copyin(en->auth_key, tls->params.auth_key,
644 en->auth_key_len);
645 if (error)
646 goto out;
647 }
648
649 tls->params.cipher_key_len = en->cipher_key_len;
650 tls->params.cipher_key = malloc(en->cipher_key_len, M_KTLS, M_WAITOK);
651 error = copyin(en->cipher_key, tls->params.cipher_key,
652 en->cipher_key_len);
653 if (error)
654 goto out;
655
656 /*
657 * This holds the implicit portion of the nonce for AEAD
658 * ciphers and the initial implicit IV for TLS 1.0. The
659 * explicit portions of the IV are generated in ktls_frame().
660 */
661 if (en->iv_len != 0) {
662 tls->params.iv_len = en->iv_len;
663 error = copyin(en->iv, tls->params.iv, en->iv_len);
664 if (error)
665 goto out;
666
667 /*
668 * For TLS 1.2 with GCM, generate an 8-byte nonce as a
669 * counter to generate unique explicit IVs.
670 *
671 * Store this counter in the last 8 bytes of the IV
672 * array so that it is 8-byte aligned.
673 */
674 if (en->cipher_algorithm == CRYPTO_AES_NIST_GCM_16 &&
675 en->tls_vminor == TLS_MINOR_VER_TWO)
676 arc4rand(tls->params.iv + 8, sizeof(uint64_t), 0);
677 }
678
679 *tlsp = tls;
680 return (0);
681
682 out:
683 ktls_free(tls);
684 return (error);
685 }
686
687 static struct ktls_session *
ktls_clone_session(struct ktls_session * tls)688 ktls_clone_session(struct ktls_session *tls)
689 {
690 struct ktls_session *tls_new;
691
692 tls_new = uma_zalloc(ktls_session_zone, M_WAITOK | M_ZERO);
693
694 counter_u64_add(ktls_offload_active, 1);
695
696 refcount_init(&tls_new->refcount, 1);
697 TASK_INIT(&tls_new->reset_tag_task, 0, ktls_reset_send_tag, tls_new);
698
699 /* Copy fields from existing session. */
700 tls_new->params = tls->params;
701 tls_new->wq_index = tls->wq_index;
702
703 /* Deep copy keys. */
704 if (tls_new->params.auth_key != NULL) {
705 tls_new->params.auth_key = malloc(tls->params.auth_key_len,
706 M_KTLS, M_WAITOK);
707 memcpy(tls_new->params.auth_key, tls->params.auth_key,
708 tls->params.auth_key_len);
709 }
710
711 tls_new->params.cipher_key = malloc(tls->params.cipher_key_len, M_KTLS,
712 M_WAITOK);
713 memcpy(tls_new->params.cipher_key, tls->params.cipher_key,
714 tls->params.cipher_key_len);
715
716 return (tls_new);
717 }
718 #endif
719
720 static void
ktls_cleanup(struct ktls_session * tls)721 ktls_cleanup(struct ktls_session *tls)
722 {
723
724 counter_u64_add(ktls_offload_active, -1);
725 switch (tls->mode) {
726 case TCP_TLS_MODE_SW:
727 MPASS(tls->be != NULL);
728 switch (tls->params.cipher_algorithm) {
729 case CRYPTO_AES_CBC:
730 counter_u64_add(ktls_sw_cbc, -1);
731 break;
732 case CRYPTO_AES_NIST_GCM_16:
733 counter_u64_add(ktls_sw_gcm, -1);
734 break;
735 case CRYPTO_CHACHA20_POLY1305:
736 counter_u64_add(ktls_sw_chacha20, -1);
737 break;
738 }
739 tls->free(tls);
740 break;
741 case TCP_TLS_MODE_IFNET:
742 switch (tls->params.cipher_algorithm) {
743 case CRYPTO_AES_CBC:
744 counter_u64_add(ktls_ifnet_cbc, -1);
745 break;
746 case CRYPTO_AES_NIST_GCM_16:
747 counter_u64_add(ktls_ifnet_gcm, -1);
748 break;
749 case CRYPTO_CHACHA20_POLY1305:
750 counter_u64_add(ktls_ifnet_chacha20, -1);
751 break;
752 }
753 if (tls->snd_tag != NULL)
754 m_snd_tag_rele(tls->snd_tag);
755 break;
756 #ifdef TCP_OFFLOAD
757 case TCP_TLS_MODE_TOE:
758 switch (tls->params.cipher_algorithm) {
759 case CRYPTO_AES_CBC:
760 counter_u64_add(ktls_toe_cbc, -1);
761 break;
762 case CRYPTO_AES_NIST_GCM_16:
763 counter_u64_add(ktls_toe_gcm, -1);
764 break;
765 case CRYPTO_CHACHA20_POLY1305:
766 counter_u64_add(ktls_toe_chacha20, -1);
767 break;
768 }
769 break;
770 #endif
771 }
772 if (tls->params.auth_key != NULL) {
773 zfree(tls->params.auth_key, M_KTLS);
774 tls->params.auth_key = NULL;
775 tls->params.auth_key_len = 0;
776 }
777 if (tls->params.cipher_key != NULL) {
778 zfree(tls->params.cipher_key, M_KTLS);
779 tls->params.cipher_key = NULL;
780 tls->params.cipher_key_len = 0;
781 }
782 explicit_bzero(tls->params.iv, sizeof(tls->params.iv));
783 }
784
785 #if defined(INET) || defined(INET6)
786
787 #ifdef TCP_OFFLOAD
788 static int
ktls_try_toe(struct socket * so,struct ktls_session * tls,int direction)789 ktls_try_toe(struct socket *so, struct ktls_session *tls, int direction)
790 {
791 struct inpcb *inp;
792 struct tcpcb *tp;
793 int error;
794
795 inp = so->so_pcb;
796 INP_WLOCK(inp);
797 if (inp->inp_flags2 & INP_FREED) {
798 INP_WUNLOCK(inp);
799 return (ECONNRESET);
800 }
801 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
802 INP_WUNLOCK(inp);
803 return (ECONNRESET);
804 }
805 if (inp->inp_socket == NULL) {
806 INP_WUNLOCK(inp);
807 return (ECONNRESET);
808 }
809 tp = intotcpcb(inp);
810 if (!(tp->t_flags & TF_TOE)) {
811 INP_WUNLOCK(inp);
812 return (EOPNOTSUPP);
813 }
814
815 error = tcp_offload_alloc_tls_session(tp, tls, direction);
816 INP_WUNLOCK(inp);
817 if (error == 0) {
818 tls->mode = TCP_TLS_MODE_TOE;
819 switch (tls->params.cipher_algorithm) {
820 case CRYPTO_AES_CBC:
821 counter_u64_add(ktls_toe_cbc, 1);
822 break;
823 case CRYPTO_AES_NIST_GCM_16:
824 counter_u64_add(ktls_toe_gcm, 1);
825 break;
826 case CRYPTO_CHACHA20_POLY1305:
827 counter_u64_add(ktls_toe_chacha20, 1);
828 break;
829 }
830 }
831 return (error);
832 }
833 #endif
834
835 /*
836 * Common code used when first enabling ifnet TLS on a connection or
837 * when allocating a new ifnet TLS session due to a routing change.
838 * This function allocates a new TLS send tag on whatever interface
839 * the connection is currently routed over.
840 */
841 static int
ktls_alloc_snd_tag(struct inpcb * inp,struct ktls_session * tls,bool force,struct m_snd_tag ** mstp)842 ktls_alloc_snd_tag(struct inpcb *inp, struct ktls_session *tls, bool force,
843 struct m_snd_tag **mstp)
844 {
845 union if_snd_tag_alloc_params params;
846 struct ifnet *ifp;
847 struct nhop_object *nh;
848 struct tcpcb *tp;
849 int error;
850
851 INP_RLOCK(inp);
852 if (inp->inp_flags2 & INP_FREED) {
853 INP_RUNLOCK(inp);
854 return (ECONNRESET);
855 }
856 if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
857 INP_RUNLOCK(inp);
858 return (ECONNRESET);
859 }
860 if (inp->inp_socket == NULL) {
861 INP_RUNLOCK(inp);
862 return (ECONNRESET);
863 }
864 tp = intotcpcb(inp);
865
866 /*
867 * Check administrative controls on ifnet TLS to determine if
868 * ifnet TLS should be denied.
869 *
870 * - Always permit 'force' requests.
871 * - ktls_ifnet_permitted == 0: always deny.
872 */
873 if (!force && ktls_ifnet_permitted == 0) {
874 INP_RUNLOCK(inp);
875 return (ENXIO);
876 }
877
878 /*
879 * XXX: Use the cached route in the inpcb to find the
880 * interface. This should perhaps instead use
881 * rtalloc1_fib(dst, 0, 0, fibnum). Since KTLS is only
882 * enabled after a connection has completed key negotiation in
883 * userland, the cached route will be present in practice.
884 */
885 nh = inp->inp_route.ro_nh;
886 if (nh == NULL) {
887 INP_RUNLOCK(inp);
888 return (ENXIO);
889 }
890 ifp = nh->nh_ifp;
891 if_ref(ifp);
892
893 /*
894 * Allocate a TLS + ratelimit tag if the connection has an
895 * existing pacing rate.
896 */
897 if (tp->t_pacing_rate != -1 &&
898 (ifp->if_capenable & IFCAP_TXTLS_RTLMT) != 0) {
899 params.hdr.type = IF_SND_TAG_TYPE_TLS_RATE_LIMIT;
900 params.tls_rate_limit.inp = inp;
901 params.tls_rate_limit.tls = tls;
902 params.tls_rate_limit.max_rate = tp->t_pacing_rate;
903 } else {
904 params.hdr.type = IF_SND_TAG_TYPE_TLS;
905 params.tls.inp = inp;
906 params.tls.tls = tls;
907 }
908 params.hdr.flowid = inp->inp_flowid;
909 params.hdr.flowtype = inp->inp_flowtype;
910 params.hdr.numa_domain = inp->inp_numa_domain;
911 INP_RUNLOCK(inp);
912
913 if ((ifp->if_capenable & IFCAP_MEXTPG) == 0) {
914 error = EOPNOTSUPP;
915 goto out;
916 }
917 if (inp->inp_vflag & INP_IPV6) {
918 if ((ifp->if_capenable & IFCAP_TXTLS6) == 0) {
919 error = EOPNOTSUPP;
920 goto out;
921 }
922 } else {
923 if ((ifp->if_capenable & IFCAP_TXTLS4) == 0) {
924 error = EOPNOTSUPP;
925 goto out;
926 }
927 }
928 error = m_snd_tag_alloc(ifp, ¶ms, mstp);
929 out:
930 if_rele(ifp);
931 return (error);
932 }
933
934 static int
ktls_try_ifnet(struct socket * so,struct ktls_session * tls,bool force)935 ktls_try_ifnet(struct socket *so, struct ktls_session *tls, bool force)
936 {
937 struct m_snd_tag *mst;
938 int error;
939
940 error = ktls_alloc_snd_tag(so->so_pcb, tls, force, &mst);
941 if (error == 0) {
942 tls->mode = TCP_TLS_MODE_IFNET;
943 tls->snd_tag = mst;
944 switch (tls->params.cipher_algorithm) {
945 case CRYPTO_AES_CBC:
946 counter_u64_add(ktls_ifnet_cbc, 1);
947 break;
948 case CRYPTO_AES_NIST_GCM_16:
949 counter_u64_add(ktls_ifnet_gcm, 1);
950 break;
951 case CRYPTO_CHACHA20_POLY1305:
952 counter_u64_add(ktls_ifnet_chacha20, 1);
953 break;
954 }
955 }
956 return (error);
957 }
958
959 static int
ktls_try_sw(struct socket * so,struct ktls_session * tls,int direction)960 ktls_try_sw(struct socket *so, struct ktls_session *tls, int direction)
961 {
962 struct rm_priotracker prio;
963 struct ktls_crypto_backend *be;
964
965 /*
966 * Choose the best software crypto backend. Backends are
967 * stored in sorted priority order (larget value == most
968 * important at the head of the list), so this just stops on
969 * the first backend that claims the session by returning
970 * success.
971 */
972 if (ktls_allow_unload)
973 rm_rlock(&ktls_backends_lock, &prio);
974 LIST_FOREACH(be, &ktls_backends, next) {
975 if (be->try(so, tls, direction) == 0)
976 break;
977 KASSERT(tls->cipher == NULL,
978 ("ktls backend leaked a cipher pointer"));
979 }
980 if (be != NULL) {
981 if (ktls_allow_unload)
982 be->use_count++;
983 tls->be = be;
984 }
985 if (ktls_allow_unload)
986 rm_runlock(&ktls_backends_lock, &prio);
987 if (be == NULL)
988 return (EOPNOTSUPP);
989 tls->mode = TCP_TLS_MODE_SW;
990 switch (tls->params.cipher_algorithm) {
991 case CRYPTO_AES_CBC:
992 counter_u64_add(ktls_sw_cbc, 1);
993 break;
994 case CRYPTO_AES_NIST_GCM_16:
995 counter_u64_add(ktls_sw_gcm, 1);
996 break;
997 case CRYPTO_CHACHA20_POLY1305:
998 counter_u64_add(ktls_sw_chacha20, 1);
999 break;
1000 }
1001 return (0);
1002 }
1003
1004 /*
1005 * KTLS RX stores data in the socket buffer as a list of TLS records,
1006 * where each record is stored as a control message containg the TLS
1007 * header followed by data mbufs containing the decrypted data. This
1008 * is different from KTLS TX which always uses an mb_ext_pgs mbuf for
1009 * both encrypted and decrypted data. TLS records decrypted by a NIC
1010 * should be queued to the socket buffer as records, but encrypted
1011 * data which needs to be decrypted by software arrives as a stream of
1012 * regular mbufs which need to be converted. In addition, there may
1013 * already be pending encrypted data in the socket buffer when KTLS RX
1014 * is enabled.
1015 *
1016 * To manage not-yet-decrypted data for KTLS RX, the following scheme
1017 * is used:
1018 *
1019 * - A single chain of NOTREADY mbufs is hung off of sb_mtls.
1020 *
1021 * - ktls_check_rx checks this chain of mbufs reading the TLS header
1022 * from the first mbuf. Once all of the data for that TLS record is
1023 * queued, the socket is queued to a worker thread.
1024 *
1025 * - The worker thread calls ktls_decrypt to decrypt TLS records in
1026 * the TLS chain. Each TLS record is detached from the TLS chain,
1027 * decrypted, and inserted into the regular socket buffer chain as
1028 * record starting with a control message holding the TLS header and
1029 * a chain of mbufs holding the encrypted data.
1030 */
1031
1032 static void
sb_mark_notready(struct sockbuf * sb)1033 sb_mark_notready(struct sockbuf *sb)
1034 {
1035 struct mbuf *m;
1036
1037 m = sb->sb_mb;
1038 sb->sb_mtls = m;
1039 sb->sb_mb = NULL;
1040 sb->sb_mbtail = NULL;
1041 sb->sb_lastrecord = NULL;
1042 for (; m != NULL; m = m->m_next) {
1043 KASSERT(m->m_nextpkt == NULL, ("%s: m_nextpkt != NULL",
1044 __func__));
1045 KASSERT((m->m_flags & M_NOTAVAIL) == 0, ("%s: mbuf not avail",
1046 __func__));
1047 KASSERT(sb->sb_acc >= m->m_len, ("%s: sb_acc < m->m_len",
1048 __func__));
1049 m->m_flags |= M_NOTREADY;
1050 sb->sb_acc -= m->m_len;
1051 sb->sb_tlscc += m->m_len;
1052 sb->sb_mtlstail = m;
1053 }
1054 KASSERT(sb->sb_acc == 0 && sb->sb_tlscc == sb->sb_ccc,
1055 ("%s: acc %u tlscc %u ccc %u", __func__, sb->sb_acc, sb->sb_tlscc,
1056 sb->sb_ccc));
1057 }
1058
1059 int
ktls_enable_rx(struct socket * so,struct tls_enable * en)1060 ktls_enable_rx(struct socket *so, struct tls_enable *en)
1061 {
1062 struct ktls_session *tls;
1063 int error;
1064
1065 if (!ktls_offload_enable)
1066 return (ENOTSUP);
1067 if (SOLISTENING(so))
1068 return (EINVAL);
1069
1070 counter_u64_add(ktls_offload_enable_calls, 1);
1071
1072 /*
1073 * This should always be true since only the TCP socket option
1074 * invokes this function.
1075 */
1076 if (so->so_proto->pr_protocol != IPPROTO_TCP)
1077 return (EINVAL);
1078
1079 /*
1080 * XXX: Don't overwrite existing sessions. We should permit
1081 * this to support rekeying in the future.
1082 */
1083 if (so->so_rcv.sb_tls_info != NULL)
1084 return (EALREADY);
1085
1086 if (en->cipher_algorithm == CRYPTO_AES_CBC && !ktls_cbc_enable)
1087 return (ENOTSUP);
1088
1089 error = ktls_create_session(so, en, &tls);
1090 if (error)
1091 return (error);
1092
1093 #ifdef TCP_OFFLOAD
1094 error = ktls_try_toe(so, tls, KTLS_RX);
1095 if (error)
1096 #endif
1097 error = ktls_try_sw(so, tls, KTLS_RX);
1098
1099 if (error) {
1100 ktls_free(tls);
1101 return (error);
1102 }
1103
1104 /* Mark the socket as using TLS offload. */
1105 SOCKBUF_LOCK(&so->so_rcv);
1106 so->so_rcv.sb_tls_seqno = be64dec(en->rec_seq);
1107 so->so_rcv.sb_tls_info = tls;
1108 so->so_rcv.sb_flags |= SB_TLS_RX;
1109
1110 /* Mark existing data as not ready until it can be decrypted. */
1111 if (tls->mode != TCP_TLS_MODE_TOE) {
1112 sb_mark_notready(&so->so_rcv);
1113 ktls_check_rx(&so->so_rcv);
1114 }
1115 SOCKBUF_UNLOCK(&so->so_rcv);
1116
1117 counter_u64_add(ktls_offload_total, 1);
1118
1119 return (0);
1120 }
1121
1122 int
ktls_enable_tx(struct socket * so,struct tls_enable * en)1123 ktls_enable_tx(struct socket *so, struct tls_enable *en)
1124 {
1125 struct ktls_session *tls;
1126 struct inpcb *inp;
1127 int error;
1128
1129 if (!ktls_offload_enable)
1130 return (ENOTSUP);
1131 if (SOLISTENING(so))
1132 return (EINVAL);
1133
1134 counter_u64_add(ktls_offload_enable_calls, 1);
1135
1136 /*
1137 * This should always be true since only the TCP socket option
1138 * invokes this function.
1139 */
1140 if (so->so_proto->pr_protocol != IPPROTO_TCP)
1141 return (EINVAL);
1142
1143 /*
1144 * XXX: Don't overwrite existing sessions. We should permit
1145 * this to support rekeying in the future.
1146 */
1147 if (so->so_snd.sb_tls_info != NULL)
1148 return (EALREADY);
1149
1150 if (en->cipher_algorithm == CRYPTO_AES_CBC && !ktls_cbc_enable)
1151 return (ENOTSUP);
1152
1153 /* TLS requires ext pgs */
1154 if (mb_use_ext_pgs == 0)
1155 return (ENXIO);
1156
1157 error = ktls_create_session(so, en, &tls);
1158 if (error)
1159 return (error);
1160
1161 /* Prefer TOE -> ifnet TLS -> software TLS. */
1162 #ifdef TCP_OFFLOAD
1163 error = ktls_try_toe(so, tls, KTLS_TX);
1164 if (error)
1165 #endif
1166 error = ktls_try_ifnet(so, tls, false);
1167 if (error)
1168 error = ktls_try_sw(so, tls, KTLS_TX);
1169
1170 if (error) {
1171 ktls_free(tls);
1172 return (error);
1173 }
1174
1175 error = SOCK_IO_SEND_LOCK(so, SBL_WAIT);
1176 if (error) {
1177 ktls_free(tls);
1178 return (error);
1179 }
1180
1181 /*
1182 * Write lock the INP when setting sb_tls_info so that
1183 * routines in tcp_ratelimit.c can read sb_tls_info while
1184 * holding the INP lock.
1185 */
1186 inp = so->so_pcb;
1187 INP_WLOCK(inp);
1188 SOCKBUF_LOCK(&so->so_snd);
1189 so->so_snd.sb_tls_seqno = be64dec(en->rec_seq);
1190 so->so_snd.sb_tls_info = tls;
1191 if (tls->mode != TCP_TLS_MODE_SW)
1192 so->so_snd.sb_flags |= SB_TLS_IFNET;
1193 SOCKBUF_UNLOCK(&so->so_snd);
1194 INP_WUNLOCK(inp);
1195 SOCK_IO_SEND_UNLOCK(so);
1196
1197 counter_u64_add(ktls_offload_total, 1);
1198
1199 return (0);
1200 }
1201
1202 int
ktls_get_rx_mode(struct socket * so)1203 ktls_get_rx_mode(struct socket *so)
1204 {
1205 struct ktls_session *tls;
1206 struct inpcb *inp;
1207 int mode;
1208
1209 if (SOLISTENING(so))
1210 return (EINVAL);
1211 inp = so->so_pcb;
1212 INP_WLOCK_ASSERT(inp);
1213 SOCKBUF_LOCK(&so->so_rcv);
1214 tls = so->so_rcv.sb_tls_info;
1215 if (tls == NULL)
1216 mode = TCP_TLS_MODE_NONE;
1217 else
1218 mode = tls->mode;
1219 SOCKBUF_UNLOCK(&so->so_rcv);
1220 return (mode);
1221 }
1222
1223 int
ktls_get_tx_mode(struct socket * so)1224 ktls_get_tx_mode(struct socket *so)
1225 {
1226 struct ktls_session *tls;
1227 struct inpcb *inp;
1228 int mode;
1229
1230 if (SOLISTENING(so))
1231 return (EINVAL);
1232 inp = so->so_pcb;
1233 INP_WLOCK_ASSERT(inp);
1234 SOCKBUF_LOCK(&so->so_snd);
1235 tls = so->so_snd.sb_tls_info;
1236 if (tls == NULL)
1237 mode = TCP_TLS_MODE_NONE;
1238 else
1239 mode = tls->mode;
1240 SOCKBUF_UNLOCK(&so->so_snd);
1241 return (mode);
1242 }
1243
1244 /*
1245 * Switch between SW and ifnet TLS sessions as requested.
1246 */
1247 int
ktls_set_tx_mode(struct socket * so,int mode)1248 ktls_set_tx_mode(struct socket *so, int mode)
1249 {
1250 struct ktls_session *tls, *tls_new;
1251 struct inpcb *inp;
1252 int error;
1253
1254 if (SOLISTENING(so))
1255 return (EINVAL);
1256 switch (mode) {
1257 case TCP_TLS_MODE_SW:
1258 case TCP_TLS_MODE_IFNET:
1259 break;
1260 default:
1261 return (EINVAL);
1262 }
1263
1264 inp = so->so_pcb;
1265 INP_WLOCK_ASSERT(inp);
1266 SOCKBUF_LOCK(&so->so_snd);
1267 tls = so->so_snd.sb_tls_info;
1268 if (tls == NULL) {
1269 SOCKBUF_UNLOCK(&so->so_snd);
1270 return (0);
1271 }
1272
1273 if (tls->mode == mode) {
1274 SOCKBUF_UNLOCK(&so->so_snd);
1275 return (0);
1276 }
1277
1278 tls = ktls_hold(tls);
1279 SOCKBUF_UNLOCK(&so->so_snd);
1280 INP_WUNLOCK(inp);
1281
1282 tls_new = ktls_clone_session(tls);
1283
1284 if (mode == TCP_TLS_MODE_IFNET)
1285 error = ktls_try_ifnet(so, tls_new, true);
1286 else
1287 error = ktls_try_sw(so, tls_new, KTLS_TX);
1288 if (error) {
1289 counter_u64_add(ktls_switch_failed, 1);
1290 ktls_free(tls_new);
1291 ktls_free(tls);
1292 INP_WLOCK(inp);
1293 return (error);
1294 }
1295
1296 error = SOCK_IO_SEND_LOCK(so, SBL_WAIT);
1297 if (error) {
1298 counter_u64_add(ktls_switch_failed, 1);
1299 ktls_free(tls_new);
1300 ktls_free(tls);
1301 INP_WLOCK(inp);
1302 return (error);
1303 }
1304
1305 /*
1306 * If we raced with another session change, keep the existing
1307 * session.
1308 */
1309 if (tls != so->so_snd.sb_tls_info) {
1310 counter_u64_add(ktls_switch_failed, 1);
1311 SOCK_IO_SEND_UNLOCK(so);
1312 ktls_free(tls_new);
1313 ktls_free(tls);
1314 INP_WLOCK(inp);
1315 return (EBUSY);
1316 }
1317
1318 INP_WLOCK(inp);
1319 SOCKBUF_LOCK(&so->so_snd);
1320 so->so_snd.sb_tls_info = tls_new;
1321 if (tls_new->mode != TCP_TLS_MODE_SW)
1322 so->so_snd.sb_flags |= SB_TLS_IFNET;
1323 SOCKBUF_UNLOCK(&so->so_snd);
1324 SOCK_IO_SEND_UNLOCK(so);
1325
1326 /*
1327 * Drop two references on 'tls'. The first is for the
1328 * ktls_hold() above. The second drops the reference from the
1329 * socket buffer.
1330 */
1331 KASSERT(tls->refcount >= 2, ("too few references on old session"));
1332 ktls_free(tls);
1333 ktls_free(tls);
1334
1335 if (mode == TCP_TLS_MODE_IFNET)
1336 counter_u64_add(ktls_switch_to_ifnet, 1);
1337 else
1338 counter_u64_add(ktls_switch_to_sw, 1);
1339
1340 return (0);
1341 }
1342
1343 /*
1344 * Try to allocate a new TLS send tag. This task is scheduled when
1345 * ip_output detects a route change while trying to transmit a packet
1346 * holding a TLS record. If a new tag is allocated, replace the tag
1347 * in the TLS session. Subsequent packets on the connection will use
1348 * the new tag. If a new tag cannot be allocated, drop the
1349 * connection.
1350 */
1351 static void
ktls_reset_send_tag(void * context,int pending)1352 ktls_reset_send_tag(void *context, int pending)
1353 {
1354 struct epoch_tracker et;
1355 struct ktls_session *tls;
1356 struct m_snd_tag *old, *new;
1357 struct inpcb *inp;
1358 struct tcpcb *tp;
1359 int error;
1360
1361 MPASS(pending == 1);
1362
1363 tls = context;
1364 inp = tls->inp;
1365
1366 /*
1367 * Free the old tag first before allocating a new one.
1368 * ip[6]_output_send() will treat a NULL send tag the same as
1369 * an ifp mismatch and drop packets until a new tag is
1370 * allocated.
1371 *
1372 * Write-lock the INP when changing tls->snd_tag since
1373 * ip[6]_output_send() holds a read-lock when reading the
1374 * pointer.
1375 */
1376 INP_WLOCK(inp);
1377 old = tls->snd_tag;
1378 tls->snd_tag = NULL;
1379 INP_WUNLOCK(inp);
1380 if (old != NULL)
1381 m_snd_tag_rele(old);
1382
1383 error = ktls_alloc_snd_tag(inp, tls, true, &new);
1384
1385 if (error == 0) {
1386 INP_WLOCK(inp);
1387 tls->snd_tag = new;
1388 mtx_pool_lock(mtxpool_sleep, tls);
1389 tls->reset_pending = false;
1390 mtx_pool_unlock(mtxpool_sleep, tls);
1391 if (!in_pcbrele_wlocked(inp))
1392 INP_WUNLOCK(inp);
1393
1394 counter_u64_add(ktls_ifnet_reset, 1);
1395
1396 /*
1397 * XXX: Should we kick tcp_output explicitly now that
1398 * the send tag is fixed or just rely on timers?
1399 */
1400 } else {
1401 NET_EPOCH_ENTER(et);
1402 INP_WLOCK(inp);
1403 if (!in_pcbrele_wlocked(inp)) {
1404 if (!(inp->inp_flags & INP_TIMEWAIT) &&
1405 !(inp->inp_flags & INP_DROPPED)) {
1406 tp = intotcpcb(inp);
1407 CURVNET_SET(tp->t_vnet);
1408 tp = tcp_drop(tp, ECONNABORTED);
1409 CURVNET_RESTORE();
1410 if (tp != NULL)
1411 INP_WUNLOCK(inp);
1412 counter_u64_add(ktls_ifnet_reset_dropped, 1);
1413 } else
1414 INP_WUNLOCK(inp);
1415 }
1416 NET_EPOCH_EXIT(et);
1417
1418 counter_u64_add(ktls_ifnet_reset_failed, 1);
1419
1420 /*
1421 * Leave reset_pending true to avoid future tasks while
1422 * the socket goes away.
1423 */
1424 }
1425
1426 ktls_free(tls);
1427 }
1428
1429 int
ktls_output_eagain(struct inpcb * inp,struct ktls_session * tls)1430 ktls_output_eagain(struct inpcb *inp, struct ktls_session *tls)
1431 {
1432
1433 if (inp == NULL)
1434 return (ENOBUFS);
1435
1436 INP_LOCK_ASSERT(inp);
1437
1438 /*
1439 * See if we should schedule a task to update the send tag for
1440 * this session.
1441 */
1442 mtx_pool_lock(mtxpool_sleep, tls);
1443 if (!tls->reset_pending) {
1444 (void) ktls_hold(tls);
1445 in_pcbref(inp);
1446 tls->inp = inp;
1447 tls->reset_pending = true;
1448 taskqueue_enqueue(taskqueue_thread, &tls->reset_tag_task);
1449 }
1450 mtx_pool_unlock(mtxpool_sleep, tls);
1451 return (ENOBUFS);
1452 }
1453
1454 #ifdef RATELIMIT
1455 int
ktls_modify_txrtlmt(struct ktls_session * tls,uint64_t max_pacing_rate)1456 ktls_modify_txrtlmt(struct ktls_session *tls, uint64_t max_pacing_rate)
1457 {
1458 union if_snd_tag_modify_params params = {
1459 .rate_limit.max_rate = max_pacing_rate,
1460 .rate_limit.flags = M_NOWAIT,
1461 };
1462 struct m_snd_tag *mst;
1463 struct ifnet *ifp;
1464 int error;
1465
1466 /* Can't get to the inp, but it should be locked. */
1467 /* INP_LOCK_ASSERT(inp); */
1468
1469 MPASS(tls->mode == TCP_TLS_MODE_IFNET);
1470
1471 if (tls->snd_tag == NULL) {
1472 /*
1473 * Resetting send tag, ignore this change. The
1474 * pending reset may or may not see this updated rate
1475 * in the tcpcb. If it doesn't, we will just lose
1476 * this rate change.
1477 */
1478 return (0);
1479 }
1480
1481 mst = tls->snd_tag;
1482
1483 MPASS(mst != NULL);
1484 MPASS(mst->type == IF_SND_TAG_TYPE_TLS_RATE_LIMIT);
1485
1486 ifp = mst->ifp;
1487 return (ifp->if_snd_tag_modify(mst, ¶ms));
1488 }
1489 #endif
1490 #endif
1491
1492 void
ktls_destroy(struct ktls_session * tls)1493 ktls_destroy(struct ktls_session *tls)
1494 {
1495 struct rm_priotracker prio;
1496
1497 if (tls->sequential_records) {
1498 struct mbuf *m, *n;
1499 int page_count;
1500
1501 STAILQ_FOREACH_SAFE(m, &tls->pending_records, m_epg_stailq, n) {
1502 page_count = m->m_epg_enc_cnt;
1503 while (page_count > 0) {
1504 KASSERT(page_count >= m->m_epg_nrdy,
1505 ("%s: too few pages", __func__));
1506 page_count -= m->m_epg_nrdy;
1507 m = m_free(m);
1508 }
1509 }
1510 }
1511 ktls_cleanup(tls);
1512 if (tls->be != NULL && ktls_allow_unload) {
1513 rm_rlock(&ktls_backends_lock, &prio);
1514 tls->be->use_count--;
1515 rm_runlock(&ktls_backends_lock, &prio);
1516 }
1517 uma_zfree(ktls_session_zone, tls);
1518 }
1519
1520 void
ktls_seq(struct sockbuf * sb,struct mbuf * m)1521 ktls_seq(struct sockbuf *sb, struct mbuf *m)
1522 {
1523
1524 for (; m != NULL; m = m->m_next) {
1525 KASSERT((m->m_flags & M_EXTPG) != 0,
1526 ("ktls_seq: mapped mbuf %p", m));
1527
1528 m->m_epg_seqno = sb->sb_tls_seqno;
1529 sb->sb_tls_seqno++;
1530 }
1531 }
1532
1533 /*
1534 * Add TLS framing (headers and trailers) to a chain of mbufs. Each
1535 * mbuf in the chain must be an unmapped mbuf. The payload of the
1536 * mbuf must be populated with the payload of each TLS record.
1537 *
1538 * The record_type argument specifies the TLS record type used when
1539 * populating the TLS header.
1540 *
1541 * The enq_count argument on return is set to the number of pages of
1542 * payload data for this entire chain that need to be encrypted via SW
1543 * encryption. The returned value should be passed to ktls_enqueue
1544 * when scheduling encryption of this chain of mbufs. To handle the
1545 * special case of empty fragments for TLS 1.0 sessions, an empty
1546 * fragment counts as one page.
1547 */
1548 void
ktls_frame(struct mbuf * top,struct ktls_session * tls,int * enq_cnt,uint8_t record_type)1549 ktls_frame(struct mbuf *top, struct ktls_session *tls, int *enq_cnt,
1550 uint8_t record_type)
1551 {
1552 struct tls_record_layer *tlshdr;
1553 struct mbuf *m;
1554 uint64_t *noncep;
1555 uint16_t tls_len;
1556 int maxlen;
1557
1558 maxlen = tls->params.max_frame_len;
1559 *enq_cnt = 0;
1560 for (m = top; m != NULL; m = m->m_next) {
1561 /*
1562 * All mbufs in the chain should be TLS records whose
1563 * payload does not exceed the maximum frame length.
1564 *
1565 * Empty TLS 1.0 records are permitted when using CBC.
1566 */
1567 KASSERT(m->m_len <= maxlen && m->m_len >= 0 &&
1568 (m->m_len > 0 || ktls_permit_empty_frames(tls)),
1569 ("ktls_frame: m %p len %d", m, m->m_len));
1570
1571 /*
1572 * TLS frames require unmapped mbufs to store session
1573 * info.
1574 */
1575 KASSERT((m->m_flags & M_EXTPG) != 0,
1576 ("ktls_frame: mapped mbuf %p (top = %p)", m, top));
1577
1578 tls_len = m->m_len;
1579
1580 /* Save a reference to the session. */
1581 m->m_epg_tls = ktls_hold(tls);
1582
1583 m->m_epg_hdrlen = tls->params.tls_hlen;
1584 m->m_epg_trllen = tls->params.tls_tlen;
1585 if (tls->params.cipher_algorithm == CRYPTO_AES_CBC) {
1586 int bs, delta;
1587
1588 /*
1589 * AES-CBC pads messages to a multiple of the
1590 * block size. Note that the padding is
1591 * applied after the digest and the encryption
1592 * is done on the "plaintext || mac || padding".
1593 * At least one byte of padding is always
1594 * present.
1595 *
1596 * Compute the final trailer length assuming
1597 * at most one block of padding.
1598 * tls->params.sb_tls_tlen is the maximum
1599 * possible trailer length (padding + digest).
1600 * delta holds the number of excess padding
1601 * bytes if the maximum were used. Those
1602 * extra bytes are removed.
1603 */
1604 bs = tls->params.tls_bs;
1605 delta = (tls_len + tls->params.tls_tlen) & (bs - 1);
1606 m->m_epg_trllen -= delta;
1607 }
1608 m->m_len += m->m_epg_hdrlen + m->m_epg_trllen;
1609
1610 /* Populate the TLS header. */
1611 tlshdr = (void *)m->m_epg_hdr;
1612 tlshdr->tls_vmajor = tls->params.tls_vmajor;
1613
1614 /*
1615 * TLS 1.3 masquarades as TLS 1.2 with a record type
1616 * of TLS_RLTYPE_APP.
1617 */
1618 if (tls->params.tls_vminor == TLS_MINOR_VER_THREE &&
1619 tls->params.tls_vmajor == TLS_MAJOR_VER_ONE) {
1620 tlshdr->tls_vminor = TLS_MINOR_VER_TWO;
1621 tlshdr->tls_type = TLS_RLTYPE_APP;
1622 /* save the real record type for later */
1623 m->m_epg_record_type = record_type;
1624 m->m_epg_trail[0] = record_type;
1625 } else {
1626 tlshdr->tls_vminor = tls->params.tls_vminor;
1627 tlshdr->tls_type = record_type;
1628 }
1629 tlshdr->tls_length = htons(m->m_len - sizeof(*tlshdr));
1630
1631 /*
1632 * Store nonces / explicit IVs after the end of the
1633 * TLS header.
1634 *
1635 * For GCM with TLS 1.2, an 8 byte nonce is copied
1636 * from the end of the IV. The nonce is then
1637 * incremented for use by the next record.
1638 *
1639 * For CBC, a random nonce is inserted for TLS 1.1+.
1640 */
1641 if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16 &&
1642 tls->params.tls_vminor == TLS_MINOR_VER_TWO) {
1643 noncep = (uint64_t *)(tls->params.iv + 8);
1644 be64enc(tlshdr + 1, *noncep);
1645 (*noncep)++;
1646 } else if (tls->params.cipher_algorithm == CRYPTO_AES_CBC &&
1647 tls->params.tls_vminor >= TLS_MINOR_VER_ONE)
1648 arc4rand(tlshdr + 1, AES_BLOCK_LEN, 0);
1649
1650 /*
1651 * When using SW encryption, mark the mbuf not ready.
1652 * It will be marked ready via sbready() after the
1653 * record has been encrypted.
1654 *
1655 * When using ifnet TLS, unencrypted TLS records are
1656 * sent down the stack to the NIC.
1657 */
1658 if (tls->mode == TCP_TLS_MODE_SW) {
1659 m->m_flags |= M_NOTREADY;
1660 if (__predict_false(tls_len == 0)) {
1661 /* TLS 1.0 empty fragment. */
1662 m->m_epg_nrdy = 1;
1663 } else
1664 m->m_epg_nrdy = m->m_epg_npgs;
1665 *enq_cnt += m->m_epg_nrdy;
1666 }
1667 }
1668 }
1669
1670 bool
ktls_permit_empty_frames(struct ktls_session * tls)1671 ktls_permit_empty_frames(struct ktls_session *tls)
1672 {
1673 return (tls->params.cipher_algorithm == CRYPTO_AES_CBC &&
1674 tls->params.tls_vminor == TLS_MINOR_VER_ZERO);
1675 }
1676
1677 void
ktls_check_rx(struct sockbuf * sb)1678 ktls_check_rx(struct sockbuf *sb)
1679 {
1680 struct tls_record_layer hdr;
1681 struct ktls_wq *wq;
1682 struct socket *so;
1683 bool running;
1684
1685 SOCKBUF_LOCK_ASSERT(sb);
1686 KASSERT(sb->sb_flags & SB_TLS_RX, ("%s: sockbuf %p isn't TLS RX",
1687 __func__, sb));
1688 so = __containerof(sb, struct socket, so_rcv);
1689
1690 if (sb->sb_flags & SB_TLS_RX_RUNNING)
1691 return;
1692
1693 /* Is there enough queued for a TLS header? */
1694 if (sb->sb_tlscc < sizeof(hdr)) {
1695 if ((sb->sb_state & SBS_CANTRCVMORE) != 0 && sb->sb_tlscc != 0)
1696 so->so_error = EMSGSIZE;
1697 return;
1698 }
1699
1700 m_copydata(sb->sb_mtls, 0, sizeof(hdr), (void *)&hdr);
1701
1702 /* Is the entire record queued? */
1703 if (sb->sb_tlscc < sizeof(hdr) + ntohs(hdr.tls_length)) {
1704 if ((sb->sb_state & SBS_CANTRCVMORE) != 0)
1705 so->so_error = EMSGSIZE;
1706 return;
1707 }
1708
1709 sb->sb_flags |= SB_TLS_RX_RUNNING;
1710
1711 soref(so);
1712 wq = &ktls_wq[so->so_rcv.sb_tls_info->wq_index];
1713 mtx_lock(&wq->mtx);
1714 STAILQ_INSERT_TAIL(&wq->so_head, so, so_ktls_rx_list);
1715 running = wq->running;
1716 mtx_unlock(&wq->mtx);
1717 if (!running)
1718 wakeup(wq);
1719 counter_u64_add(ktls_cnt_rx_queued, 1);
1720 }
1721
1722 static struct mbuf *
ktls_detach_record(struct sockbuf * sb,int len)1723 ktls_detach_record(struct sockbuf *sb, int len)
1724 {
1725 struct mbuf *m, *n, *top;
1726 int remain;
1727
1728 SOCKBUF_LOCK_ASSERT(sb);
1729 MPASS(len <= sb->sb_tlscc);
1730
1731 /*
1732 * If TLS chain is the exact size of the record,
1733 * just grab the whole record.
1734 */
1735 top = sb->sb_mtls;
1736 if (sb->sb_tlscc == len) {
1737 sb->sb_mtls = NULL;
1738 sb->sb_mtlstail = NULL;
1739 goto out;
1740 }
1741
1742 /*
1743 * While it would be nice to use m_split() here, we need
1744 * to know exactly what m_split() allocates to update the
1745 * accounting, so do it inline instead.
1746 */
1747 remain = len;
1748 for (m = top; remain > m->m_len; m = m->m_next)
1749 remain -= m->m_len;
1750
1751 /* Easy case: don't have to split 'm'. */
1752 if (remain == m->m_len) {
1753 sb->sb_mtls = m->m_next;
1754 if (sb->sb_mtls == NULL)
1755 sb->sb_mtlstail = NULL;
1756 m->m_next = NULL;
1757 goto out;
1758 }
1759
1760 /*
1761 * Need to allocate an mbuf to hold the remainder of 'm'. Try
1762 * with M_NOWAIT first.
1763 */
1764 n = m_get(M_NOWAIT, MT_DATA);
1765 if (n == NULL) {
1766 /*
1767 * Use M_WAITOK with socket buffer unlocked. If
1768 * 'sb_mtls' changes while the lock is dropped, return
1769 * NULL to force the caller to retry.
1770 */
1771 SOCKBUF_UNLOCK(sb);
1772
1773 n = m_get(M_WAITOK, MT_DATA);
1774
1775 SOCKBUF_LOCK(sb);
1776 if (sb->sb_mtls != top) {
1777 m_free(n);
1778 return (NULL);
1779 }
1780 }
1781 n->m_flags |= M_NOTREADY;
1782
1783 /* Store remainder in 'n'. */
1784 n->m_len = m->m_len - remain;
1785 if (m->m_flags & M_EXT) {
1786 n->m_data = m->m_data + remain;
1787 mb_dupcl(n, m);
1788 } else {
1789 bcopy(mtod(m, caddr_t) + remain, mtod(n, caddr_t), n->m_len);
1790 }
1791
1792 /* Trim 'm' and update accounting. */
1793 m->m_len -= n->m_len;
1794 sb->sb_tlscc -= n->m_len;
1795 sb->sb_ccc -= n->m_len;
1796
1797 /* Account for 'n'. */
1798 sballoc_ktls_rx(sb, n);
1799
1800 /* Insert 'n' into the TLS chain. */
1801 sb->sb_mtls = n;
1802 n->m_next = m->m_next;
1803 if (sb->sb_mtlstail == m)
1804 sb->sb_mtlstail = n;
1805
1806 /* Detach the record from the TLS chain. */
1807 m->m_next = NULL;
1808
1809 out:
1810 MPASS(m_length(top, NULL) == len);
1811 for (m = top; m != NULL; m = m->m_next)
1812 sbfree_ktls_rx(sb, m);
1813 sb->sb_tlsdcc = len;
1814 sb->sb_ccc += len;
1815 SBCHECK(sb);
1816 return (top);
1817 }
1818
1819 /*
1820 * Determine the length of the trailing zero padding and find the real
1821 * record type in the byte before the padding.
1822 *
1823 * Walking the mbuf chain backwards is clumsy, so another option would
1824 * be to scan forwards remembering the last non-zero byte before the
1825 * trailer. However, it would be expensive to scan the entire record.
1826 * Instead, find the last non-zero byte of each mbuf in the chain
1827 * keeping track of the relative offset of that nonzero byte.
1828 *
1829 * trail_len is the size of the MAC/tag on input and is set to the
1830 * size of the full trailer including padding and the record type on
1831 * return.
1832 */
1833 static int
tls13_find_record_type(struct ktls_session * tls,struct mbuf * m,int tls_len,int * trailer_len,uint8_t * record_typep)1834 tls13_find_record_type(struct ktls_session *tls, struct mbuf *m, int tls_len,
1835 int *trailer_len, uint8_t *record_typep)
1836 {
1837 char *cp;
1838 u_int digest_start, last_offset, m_len, offset;
1839 uint8_t record_type;
1840
1841 digest_start = tls_len - *trailer_len;
1842 last_offset = 0;
1843 offset = 0;
1844 for (; m != NULL && offset < digest_start;
1845 offset += m->m_len, m = m->m_next) {
1846 /* Don't look for padding in the tag. */
1847 m_len = min(digest_start - offset, m->m_len);
1848 cp = mtod(m, char *);
1849
1850 /* Find last non-zero byte in this mbuf. */
1851 while (m_len > 0 && cp[m_len - 1] == 0)
1852 m_len--;
1853 if (m_len > 0) {
1854 record_type = cp[m_len - 1];
1855 last_offset = offset + m_len;
1856 }
1857 }
1858 if (last_offset < tls->params.tls_hlen)
1859 return (EBADMSG);
1860
1861 *record_typep = record_type;
1862 *trailer_len = tls_len - last_offset + 1;
1863 return (0);
1864 }
1865
1866 static void
ktls_drop(struct socket * so,int error)1867 ktls_drop(struct socket *so, int error)
1868 {
1869 struct epoch_tracker et;
1870 struct inpcb *inp = sotoinpcb(so);
1871 struct tcpcb *tp;
1872
1873 NET_EPOCH_ENTER(et);
1874 INP_WLOCK(inp);
1875 if (!(inp->inp_flags & INP_DROPPED)) {
1876 tp = intotcpcb(inp);
1877 CURVNET_SET(inp->inp_vnet);
1878 tp = tcp_drop(tp, error);
1879 CURVNET_RESTORE();
1880 if (tp != NULL)
1881 INP_WUNLOCK(inp);
1882 } else {
1883 so->so_error = error;
1884 SOCKBUF_LOCK(&so->so_rcv);
1885 sorwakeup_locked(so);
1886 INP_WUNLOCK(inp);
1887 }
1888 NET_EPOCH_EXIT(et);
1889 }
1890
1891 static void
ktls_decrypt(struct socket * so)1892 ktls_decrypt(struct socket *so)
1893 {
1894 char tls_header[MBUF_PEXT_HDR_LEN];
1895 struct ktls_session *tls;
1896 struct sockbuf *sb;
1897 struct tls_record_layer *hdr;
1898 struct tls_get_record tgr;
1899 struct mbuf *control, *data, *m;
1900 uint64_t seqno;
1901 int error, remain, tls_len, trail_len;
1902 bool tls13;
1903 uint8_t vminor, record_type;
1904
1905 hdr = (struct tls_record_layer *)tls_header;
1906 sb = &so->so_rcv;
1907 SOCKBUF_LOCK(sb);
1908 KASSERT(sb->sb_flags & SB_TLS_RX_RUNNING,
1909 ("%s: socket %p not running", __func__, so));
1910
1911 tls = sb->sb_tls_info;
1912 MPASS(tls != NULL);
1913
1914 tls13 = (tls->params.tls_vminor == TLS_MINOR_VER_THREE);
1915 if (tls13)
1916 vminor = TLS_MINOR_VER_TWO;
1917 else
1918 vminor = tls->params.tls_vminor;
1919 for (;;) {
1920 /* Is there enough queued for a TLS header? */
1921 if (sb->sb_tlscc < tls->params.tls_hlen)
1922 break;
1923
1924 m_copydata(sb->sb_mtls, 0, tls->params.tls_hlen, tls_header);
1925 tls_len = sizeof(*hdr) + ntohs(hdr->tls_length);
1926
1927 if (hdr->tls_vmajor != tls->params.tls_vmajor ||
1928 hdr->tls_vminor != vminor)
1929 error = EINVAL;
1930 else if (tls13 && hdr->tls_type != TLS_RLTYPE_APP)
1931 error = EINVAL;
1932 else if (tls_len < tls->params.tls_hlen || tls_len >
1933 tls->params.tls_hlen + TLS_MAX_MSG_SIZE_V10_2 +
1934 tls->params.tls_tlen)
1935 error = EMSGSIZE;
1936 else
1937 error = 0;
1938 if (__predict_false(error != 0)) {
1939 /*
1940 * We have a corrupted record and are likely
1941 * out of sync. The connection isn't
1942 * recoverable at this point, so abort it.
1943 */
1944 SOCKBUF_UNLOCK(sb);
1945 counter_u64_add(ktls_offload_corrupted_records, 1);
1946
1947 ktls_drop(so, error);
1948 goto deref;
1949 }
1950
1951 /* Is the entire record queued? */
1952 if (sb->sb_tlscc < tls_len)
1953 break;
1954
1955 /*
1956 * Split out the portion of the mbuf chain containing
1957 * this TLS record.
1958 */
1959 data = ktls_detach_record(sb, tls_len);
1960 if (data == NULL)
1961 continue;
1962 MPASS(sb->sb_tlsdcc == tls_len);
1963
1964 seqno = sb->sb_tls_seqno;
1965 sb->sb_tls_seqno++;
1966 SBCHECK(sb);
1967 SOCKBUF_UNLOCK(sb);
1968
1969 error = tls->sw_decrypt(tls, hdr, data, seqno, &trail_len);
1970 if (error == 0) {
1971 if (tls13)
1972 error = tls13_find_record_type(tls, data,
1973 tls_len, &trail_len, &record_type);
1974 else
1975 record_type = hdr->tls_type;
1976 }
1977 if (error) {
1978 counter_u64_add(ktls_offload_failed_crypto, 1);
1979
1980 SOCKBUF_LOCK(sb);
1981 if (sb->sb_tlsdcc == 0) {
1982 /*
1983 * sbcut/drop/flush discarded these
1984 * mbufs.
1985 */
1986 m_freem(data);
1987 break;
1988 }
1989
1990 /*
1991 * Drop this TLS record's data, but keep
1992 * decrypting subsequent records.
1993 */
1994 sb->sb_ccc -= tls_len;
1995 sb->sb_tlsdcc = 0;
1996
1997 CURVNET_SET(so->so_vnet);
1998 so->so_error = EBADMSG;
1999 sorwakeup_locked(so);
2000 CURVNET_RESTORE();
2001
2002 m_freem(data);
2003
2004 SOCKBUF_LOCK(sb);
2005 continue;
2006 }
2007
2008 /* Allocate the control mbuf. */
2009 memset(&tgr, 0, sizeof(tgr));
2010 tgr.tls_type = record_type;
2011 tgr.tls_vmajor = hdr->tls_vmajor;
2012 tgr.tls_vminor = hdr->tls_vminor;
2013 tgr.tls_length = htobe16(tls_len - tls->params.tls_hlen -
2014 trail_len);
2015 control = sbcreatecontrol_how(&tgr, sizeof(tgr),
2016 TLS_GET_RECORD, IPPROTO_TCP, M_WAITOK);
2017
2018 SOCKBUF_LOCK(sb);
2019 if (sb->sb_tlsdcc == 0) {
2020 /* sbcut/drop/flush discarded these mbufs. */
2021 MPASS(sb->sb_tlscc == 0);
2022 m_freem(data);
2023 m_freem(control);
2024 break;
2025 }
2026
2027 /*
2028 * Clear the 'dcc' accounting in preparation for
2029 * adding the decrypted record.
2030 */
2031 sb->sb_ccc -= tls_len;
2032 sb->sb_tlsdcc = 0;
2033 SBCHECK(sb);
2034
2035 /* If there is no payload, drop all of the data. */
2036 if (tgr.tls_length == htobe16(0)) {
2037 m_freem(data);
2038 data = NULL;
2039 } else {
2040 /* Trim header. */
2041 remain = tls->params.tls_hlen;
2042 while (remain > 0) {
2043 if (data->m_len > remain) {
2044 data->m_data += remain;
2045 data->m_len -= remain;
2046 break;
2047 }
2048 remain -= data->m_len;
2049 data = m_free(data);
2050 }
2051
2052 /* Trim trailer and clear M_NOTREADY. */
2053 remain = be16toh(tgr.tls_length);
2054 m = data;
2055 for (m = data; remain > m->m_len; m = m->m_next) {
2056 m->m_flags &= ~M_NOTREADY;
2057 remain -= m->m_len;
2058 }
2059 m->m_len = remain;
2060 m_freem(m->m_next);
2061 m->m_next = NULL;
2062 m->m_flags &= ~M_NOTREADY;
2063
2064 /* Set EOR on the final mbuf. */
2065 m->m_flags |= M_EOR;
2066 }
2067
2068 sbappendcontrol_locked(sb, data, control, 0);
2069 }
2070
2071 sb->sb_flags &= ~SB_TLS_RX_RUNNING;
2072
2073 if ((sb->sb_state & SBS_CANTRCVMORE) != 0 && sb->sb_tlscc > 0)
2074 so->so_error = EMSGSIZE;
2075
2076 sorwakeup_locked(so);
2077
2078 deref:
2079 SOCKBUF_UNLOCK_ASSERT(sb);
2080
2081 CURVNET_SET(so->so_vnet);
2082 SOCK_LOCK(so);
2083 sorele(so);
2084 CURVNET_RESTORE();
2085 }
2086
2087 void
ktls_enqueue_to_free(struct mbuf * m)2088 ktls_enqueue_to_free(struct mbuf *m)
2089 {
2090 struct ktls_wq *wq;
2091 bool running;
2092
2093 /* Mark it for freeing. */
2094 m->m_epg_flags |= EPG_FLAG_2FREE;
2095 wq = &ktls_wq[m->m_epg_tls->wq_index];
2096 mtx_lock(&wq->mtx);
2097 STAILQ_INSERT_TAIL(&wq->m_head, m, m_epg_stailq);
2098 running = wq->running;
2099 mtx_unlock(&wq->mtx);
2100 if (!running)
2101 wakeup(wq);
2102 }
2103
2104 /* Number of TLS records in a batch passed to ktls_enqueue(). */
2105 static u_int
ktls_batched_records(struct mbuf * m)2106 ktls_batched_records(struct mbuf *m)
2107 {
2108 int page_count, records;
2109
2110 records = 0;
2111 page_count = m->m_epg_enc_cnt;
2112 while (page_count > 0) {
2113 records++;
2114 page_count -= m->m_epg_nrdy;
2115 m = m->m_next;
2116 }
2117 KASSERT(page_count == 0, ("%s: mismatched page count", __func__));
2118 return (records);
2119 }
2120
2121 void
ktls_enqueue(struct mbuf * m,struct socket * so,int page_count)2122 ktls_enqueue(struct mbuf *m, struct socket *so, int page_count)
2123 {
2124 struct ktls_session *tls;
2125 struct ktls_wq *wq;
2126 int queued;
2127 bool running;
2128
2129 KASSERT(((m->m_flags & (M_EXTPG | M_NOTREADY)) ==
2130 (M_EXTPG | M_NOTREADY)),
2131 ("ktls_enqueue: %p not unready & nomap mbuf\n", m));
2132 KASSERT(page_count != 0, ("enqueueing TLS mbuf with zero page count"));
2133
2134 KASSERT(m->m_epg_tls->mode == TCP_TLS_MODE_SW, ("!SW TLS mbuf"));
2135
2136 m->m_epg_enc_cnt = page_count;
2137
2138 /*
2139 * Save a pointer to the socket. The caller is responsible
2140 * for taking an additional reference via soref().
2141 */
2142 m->m_epg_so = so;
2143
2144 queued = 1;
2145 tls = m->m_epg_tls;
2146 wq = &ktls_wq[tls->wq_index];
2147 mtx_lock(&wq->mtx);
2148 if (__predict_false(tls->sequential_records)) {
2149 /*
2150 * For TLS 1.0, records must be encrypted
2151 * sequentially. For a given connection, all records
2152 * queued to the associated work queue are processed
2153 * sequentially. However, sendfile(2) might complete
2154 * I/O requests spanning multiple TLS records out of
2155 * order. Here we ensure TLS records are enqueued to
2156 * the work queue in FIFO order.
2157 *
2158 * tls->next_seqno holds the sequence number of the
2159 * next TLS record that should be enqueued to the work
2160 * queue. If this next record is not tls->next_seqno,
2161 * it must be a future record, so insert it, sorted by
2162 * TLS sequence number, into tls->pending_records and
2163 * return.
2164 *
2165 * If this TLS record matches tls->next_seqno, place
2166 * it in the work queue and then check
2167 * tls->pending_records to see if any
2168 * previously-queued records are now ready for
2169 * encryption.
2170 */
2171 if (m->m_epg_seqno != tls->next_seqno) {
2172 struct mbuf *n, *p;
2173
2174 p = NULL;
2175 STAILQ_FOREACH(n, &tls->pending_records, m_epg_stailq) {
2176 if (n->m_epg_seqno > m->m_epg_seqno)
2177 break;
2178 p = n;
2179 }
2180 if (n == NULL)
2181 STAILQ_INSERT_TAIL(&tls->pending_records, m,
2182 m_epg_stailq);
2183 else if (p == NULL)
2184 STAILQ_INSERT_HEAD(&tls->pending_records, m,
2185 m_epg_stailq);
2186 else
2187 STAILQ_INSERT_AFTER(&tls->pending_records, p, m,
2188 m_epg_stailq);
2189 mtx_unlock(&wq->mtx);
2190 counter_u64_add(ktls_cnt_tx_pending, 1);
2191 return;
2192 }
2193
2194 tls->next_seqno += ktls_batched_records(m);
2195 STAILQ_INSERT_TAIL(&wq->m_head, m, m_epg_stailq);
2196
2197 while (!STAILQ_EMPTY(&tls->pending_records)) {
2198 struct mbuf *n;
2199
2200 n = STAILQ_FIRST(&tls->pending_records);
2201 if (n->m_epg_seqno != tls->next_seqno)
2202 break;
2203
2204 queued++;
2205 STAILQ_REMOVE_HEAD(&tls->pending_records, m_epg_stailq);
2206 tls->next_seqno += ktls_batched_records(n);
2207 STAILQ_INSERT_TAIL(&wq->m_head, n, m_epg_stailq);
2208 }
2209 counter_u64_add(ktls_cnt_tx_pending, -(queued - 1));
2210 } else
2211 STAILQ_INSERT_TAIL(&wq->m_head, m, m_epg_stailq);
2212
2213 running = wq->running;
2214 mtx_unlock(&wq->mtx);
2215 if (!running)
2216 wakeup(wq);
2217 counter_u64_add(ktls_cnt_tx_queued, queued);
2218 }
2219
2220 static __noinline void
ktls_encrypt(struct mbuf * top)2221 ktls_encrypt(struct mbuf *top)
2222 {
2223 struct ktls_session *tls;
2224 struct socket *so;
2225 struct mbuf *m;
2226 vm_paddr_t parray[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
2227 struct iovec src_iov[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
2228 struct iovec dst_iov[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
2229 vm_page_t pg;
2230 int error, i, len, npages, off, total_pages;
2231 bool is_anon;
2232
2233 so = top->m_epg_so;
2234 tls = top->m_epg_tls;
2235 KASSERT(tls != NULL, ("tls = NULL, top = %p\n", top));
2236 KASSERT(so != NULL, ("so = NULL, top = %p\n", top));
2237 #ifdef INVARIANTS
2238 top->m_epg_so = NULL;
2239 #endif
2240 total_pages = top->m_epg_enc_cnt;
2241 npages = 0;
2242
2243 /*
2244 * Encrypt the TLS records in the chain of mbufs starting with
2245 * 'top'. 'total_pages' gives us a total count of pages and is
2246 * used to know when we have finished encrypting the TLS
2247 * records originally queued with 'top'.
2248 *
2249 * NB: These mbufs are queued in the socket buffer and
2250 * 'm_next' is traversing the mbufs in the socket buffer. The
2251 * socket buffer lock is not held while traversing this chain.
2252 * Since the mbufs are all marked M_NOTREADY their 'm_next'
2253 * pointers should be stable. However, the 'm_next' of the
2254 * last mbuf encrypted is not necessarily NULL. It can point
2255 * to other mbufs appended while 'top' was on the TLS work
2256 * queue.
2257 *
2258 * Each mbuf holds an entire TLS record.
2259 */
2260 error = 0;
2261 for (m = top; npages != total_pages; m = m->m_next) {
2262 KASSERT(m->m_epg_tls == tls,
2263 ("different TLS sessions in a single mbuf chain: %p vs %p",
2264 tls, m->m_epg_tls));
2265 KASSERT((m->m_flags & (M_EXTPG | M_NOTREADY)) ==
2266 (M_EXTPG | M_NOTREADY),
2267 ("%p not unready & nomap mbuf (top = %p)\n", m, top));
2268 KASSERT(npages + m->m_epg_npgs <= total_pages,
2269 ("page count mismatch: top %p, total_pages %d, m %p", top,
2270 total_pages, m));
2271
2272 /*
2273 * Generate source and destination ivoecs to pass to
2274 * the SW encryption backend. For writable mbufs, the
2275 * destination iovec is a copy of the source and
2276 * encryption is done in place. For file-backed mbufs
2277 * (from sendfile), anonymous wired pages are
2278 * allocated and assigned to the destination iovec.
2279 */
2280 is_anon = (m->m_epg_flags & EPG_FLAG_ANON) != 0;
2281
2282 off = m->m_epg_1st_off;
2283 for (i = 0; i < m->m_epg_npgs; i++, off = 0) {
2284 len = m_epg_pagelen(m, i, off);
2285 src_iov[i].iov_len = len;
2286 src_iov[i].iov_base =
2287 (char *)(void *)PHYS_TO_DMAP(m->m_epg_pa[i]) +
2288 off;
2289
2290 if (is_anon) {
2291 dst_iov[i].iov_base = src_iov[i].iov_base;
2292 dst_iov[i].iov_len = src_iov[i].iov_len;
2293 continue;
2294 }
2295 retry_page:
2296 pg = vm_page_alloc_noobj(VM_ALLOC_NODUMP |
2297 VM_ALLOC_WIRED);
2298 if (pg == NULL) {
2299 vm_wait(NULL);
2300 goto retry_page;
2301 }
2302 parray[i] = VM_PAGE_TO_PHYS(pg);
2303 dst_iov[i].iov_base =
2304 (char *)(void *)PHYS_TO_DMAP(parray[i]) + off;
2305 dst_iov[i].iov_len = len;
2306 }
2307
2308 npages += m->m_epg_nrdy;
2309
2310 error = (*tls->sw_encrypt)(tls,
2311 (const struct tls_record_layer *)m->m_epg_hdr,
2312 m->m_epg_trail, src_iov, dst_iov, i, m->m_epg_seqno,
2313 m->m_epg_record_type);
2314 if (error) {
2315 counter_u64_add(ktls_offload_failed_crypto, 1);
2316 break;
2317 }
2318
2319 /*
2320 * For file-backed mbufs, release the file-backed
2321 * pages and replace them in the ext_pgs array with
2322 * the anonymous wired pages allocated above.
2323 */
2324 if (!is_anon) {
2325 /* Free the old pages. */
2326 m->m_ext.ext_free(m);
2327
2328 /* Replace them with the new pages. */
2329 for (i = 0; i < m->m_epg_npgs; i++)
2330 m->m_epg_pa[i] = parray[i];
2331
2332 /* Use the basic free routine. */
2333 m->m_ext.ext_free = mb_free_mext_pgs;
2334
2335 /* Pages are now writable. */
2336 m->m_epg_flags |= EPG_FLAG_ANON;
2337 }
2338
2339 /*
2340 * Drop a reference to the session now that it is no
2341 * longer needed. Existing code depends on encrypted
2342 * records having no associated session vs
2343 * yet-to-be-encrypted records having an associated
2344 * session.
2345 */
2346 m->m_epg_tls = NULL;
2347 ktls_free(tls);
2348 }
2349
2350 CURVNET_SET(so->so_vnet);
2351 if (error == 0) {
2352 (void)(*so->so_proto->pr_usrreqs->pru_ready)(so, top, npages);
2353 } else {
2354 ktls_drop(so, EIO);
2355 mb_free_notready(top, total_pages);
2356 }
2357
2358 SOCK_LOCK(so);
2359 sorele(so);
2360 CURVNET_RESTORE();
2361 }
2362
2363 static void
ktls_work_thread(void * ctx)2364 ktls_work_thread(void *ctx)
2365 {
2366 struct ktls_wq *wq = ctx;
2367 struct mbuf *m, *n;
2368 struct socket *so, *son;
2369 STAILQ_HEAD(, mbuf) local_m_head;
2370 STAILQ_HEAD(, socket) local_so_head;
2371
2372 if (ktls_bind_threads > 1) {
2373 curthread->td_domain.dr_policy =
2374 DOMAINSET_PREF(PCPU_GET(domain));
2375 }
2376 #if defined(__aarch64__) || defined(__amd64__) || defined(__i386__)
2377 fpu_kern_thread(0);
2378 #endif
2379 for (;;) {
2380 mtx_lock(&wq->mtx);
2381 while (STAILQ_EMPTY(&wq->m_head) &&
2382 STAILQ_EMPTY(&wq->so_head)) {
2383 wq->running = false;
2384 mtx_sleep(wq, &wq->mtx, 0, "-", 0);
2385 wq->running = true;
2386 }
2387
2388 STAILQ_INIT(&local_m_head);
2389 STAILQ_CONCAT(&local_m_head, &wq->m_head);
2390 STAILQ_INIT(&local_so_head);
2391 STAILQ_CONCAT(&local_so_head, &wq->so_head);
2392 mtx_unlock(&wq->mtx);
2393
2394 STAILQ_FOREACH_SAFE(m, &local_m_head, m_epg_stailq, n) {
2395 if (m->m_epg_flags & EPG_FLAG_2FREE) {
2396 ktls_free(m->m_epg_tls);
2397 m_free_raw(m);
2398 } else {
2399 ktls_encrypt(m);
2400 counter_u64_add(ktls_cnt_tx_queued, -1);
2401 }
2402 }
2403
2404 STAILQ_FOREACH_SAFE(so, &local_so_head, so_ktls_rx_list, son) {
2405 ktls_decrypt(so);
2406 counter_u64_add(ktls_cnt_rx_queued, -1);
2407 }
2408 }
2409 }
2410