]> CyberLeo.Net >> Repos - FreeBSD/FreeBSD.git/blob - sys/kern/uipc_ktls.c
Fix LINT build #2 after r360292.
[FreeBSD/FreeBSD.git] / sys / kern / uipc_ktls.c
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/nhop.h>
62 #include <net/rss_config.h>
63 #endif
64 #include <net/route.h>
65 #include <net/route/nhop.h>
66 #if defined(INET) || defined(INET6)
67 #include <netinet/in.h>
68 #include <netinet/in_pcb.h>
69 #endif
70 #include <netinet/tcp_var.h>
71 #ifdef TCP_OFFLOAD
72 #include <netinet/tcp_offload.h>
73 #endif
74 #include <opencrypto/xform.h>
75 #include <vm/uma_dbg.h>
76 #include <vm/vm.h>
77 #include <vm/vm_pageout.h>
78 #include <vm/vm_page.h>
79
80 struct ktls_wq {
81         struct mtx      mtx;
82         STAILQ_HEAD(, mbuf_ext_pgs) head;
83         bool            running;
84 } __aligned(CACHE_LINE_SIZE);
85
86 static struct ktls_wq *ktls_wq;
87 static struct proc *ktls_proc;
88 LIST_HEAD(, ktls_crypto_backend) ktls_backends;
89 static struct rmlock ktls_backends_lock;
90 static uma_zone_t ktls_session_zone;
91 static uint16_t ktls_cpuid_lookup[MAXCPU];
92
93 SYSCTL_NODE(_kern_ipc, OID_AUTO, tls, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
94     "Kernel TLS offload");
95 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, stats, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
96     "Kernel TLS offload stats");
97
98 static int ktls_allow_unload;
99 SYSCTL_INT(_kern_ipc_tls, OID_AUTO, allow_unload, CTLFLAG_RDTUN,
100     &ktls_allow_unload, 0, "Allow software crypto modules to unload");
101
102 #ifdef RSS
103 static int ktls_bind_threads = 1;
104 #else
105 static int ktls_bind_threads;
106 #endif
107 SYSCTL_INT(_kern_ipc_tls, OID_AUTO, bind_threads, CTLFLAG_RDTUN,
108     &ktls_bind_threads, 0,
109     "Bind crypto threads to cores or domains at boot");
110
111 static u_int ktls_maxlen = 16384;
112 SYSCTL_UINT(_kern_ipc_tls, OID_AUTO, maxlen, CTLFLAG_RWTUN,
113     &ktls_maxlen, 0, "Maximum TLS record size");
114
115 static int ktls_number_threads;
116 SYSCTL_INT(_kern_ipc_tls_stats, OID_AUTO, threads, CTLFLAG_RD,
117     &ktls_number_threads, 0,
118     "Number of TLS threads in thread-pool");
119
120 static bool ktls_offload_enable;
121 SYSCTL_BOOL(_kern_ipc_tls, OID_AUTO, enable, CTLFLAG_RW,
122     &ktls_offload_enable, 0,
123     "Enable support for kernel TLS offload");
124
125 static bool ktls_cbc_enable = true;
126 SYSCTL_BOOL(_kern_ipc_tls, OID_AUTO, cbc_enable, CTLFLAG_RW,
127     &ktls_cbc_enable, 1,
128     "Enable Support of AES-CBC crypto for kernel TLS");
129
130 static counter_u64_t ktls_tasks_active;
131 SYSCTL_COUNTER_U64(_kern_ipc_tls, OID_AUTO, tasks_active, CTLFLAG_RD,
132     &ktls_tasks_active, "Number of active tasks");
133
134 static counter_u64_t ktls_cnt_on;
135 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, so_inqueue, CTLFLAG_RD,
136     &ktls_cnt_on, "Number of TLS records in queue to tasks for SW crypto");
137
138 static counter_u64_t ktls_offload_total;
139 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, offload_total,
140     CTLFLAG_RD, &ktls_offload_total,
141     "Total successful TLS setups (parameters set)");
142
143 static counter_u64_t ktls_offload_enable_calls;
144 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, enable_calls,
145     CTLFLAG_RD, &ktls_offload_enable_calls,
146     "Total number of TLS enable calls made");
147
148 static counter_u64_t ktls_offload_active;
149 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, active, CTLFLAG_RD,
150     &ktls_offload_active, "Total Active TLS sessions");
151
152 static counter_u64_t ktls_offload_failed_crypto;
153 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, failed_crypto, CTLFLAG_RD,
154     &ktls_offload_failed_crypto, "Total TLS crypto failures");
155
156 static counter_u64_t ktls_switch_to_ifnet;
157 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_to_ifnet, CTLFLAG_RD,
158     &ktls_switch_to_ifnet, "TLS sessions switched from SW to ifnet");
159
160 static counter_u64_t ktls_switch_to_sw;
161 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_to_sw, CTLFLAG_RD,
162     &ktls_switch_to_sw, "TLS sessions switched from ifnet to SW");
163
164 static counter_u64_t ktls_switch_failed;
165 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_failed, CTLFLAG_RD,
166     &ktls_switch_failed, "TLS sessions unable to switch between SW and ifnet");
167
168 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, sw, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
169     "Software TLS session stats");
170 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, ifnet, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
171     "Hardware (ifnet) TLS session stats");
172 #ifdef TCP_OFFLOAD
173 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, toe, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
174     "TOE TLS session stats");
175 #endif
176
177 static counter_u64_t ktls_sw_cbc;
178 SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, cbc, CTLFLAG_RD, &ktls_sw_cbc,
179     "Active number of software TLS sessions using AES-CBC");
180
181 static counter_u64_t ktls_sw_gcm;
182 SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, gcm, CTLFLAG_RD, &ktls_sw_gcm,
183     "Active number of software TLS sessions using AES-GCM");
184
185 static counter_u64_t ktls_ifnet_cbc;
186 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, cbc, CTLFLAG_RD,
187     &ktls_ifnet_cbc,
188     "Active number of ifnet TLS sessions using AES-CBC");
189
190 static counter_u64_t ktls_ifnet_gcm;
191 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, gcm, CTLFLAG_RD,
192     &ktls_ifnet_gcm,
193     "Active number of ifnet TLS sessions using AES-GCM");
194
195 static counter_u64_t ktls_ifnet_reset;
196 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset, CTLFLAG_RD,
197     &ktls_ifnet_reset, "TLS sessions updated to a new ifnet send tag");
198
199 static counter_u64_t ktls_ifnet_reset_dropped;
200 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset_dropped, CTLFLAG_RD,
201     &ktls_ifnet_reset_dropped,
202     "TLS sessions dropped after failing to update ifnet send tag");
203
204 static counter_u64_t ktls_ifnet_reset_failed;
205 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset_failed, CTLFLAG_RD,
206     &ktls_ifnet_reset_failed,
207     "TLS sessions that failed to allocate a new ifnet send tag");
208
209 static int ktls_ifnet_permitted;
210 SYSCTL_UINT(_kern_ipc_tls_ifnet, OID_AUTO, permitted, CTLFLAG_RWTUN,
211     &ktls_ifnet_permitted, 1,
212     "Whether to permit hardware (ifnet) TLS sessions");
213
214 #ifdef TCP_OFFLOAD
215 static counter_u64_t ktls_toe_cbc;
216 SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, cbc, CTLFLAG_RD,
217     &ktls_toe_cbc,
218     "Active number of TOE TLS sessions using AES-CBC");
219
220 static counter_u64_t ktls_toe_gcm;
221 SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, gcm, CTLFLAG_RD,
222     &ktls_toe_gcm,
223     "Active number of TOE TLS sessions using AES-GCM");
224 #endif
225
226 static MALLOC_DEFINE(M_KTLS, "ktls", "Kernel TLS");
227
228 static void ktls_cleanup(struct ktls_session *tls);
229 #if defined(INET) || defined(INET6)
230 static void ktls_reset_send_tag(void *context, int pending);
231 #endif
232 static void ktls_work_thread(void *ctx);
233
234 int
235 ktls_crypto_backend_register(struct ktls_crypto_backend *be)
236 {
237         struct ktls_crypto_backend *curr_be, *tmp;
238
239         if (be->api_version != KTLS_API_VERSION) {
240                 printf("KTLS: API version mismatch (%d vs %d) for %s\n",
241                     be->api_version, KTLS_API_VERSION,
242                     be->name);
243                 return (EINVAL);
244         }
245
246         rm_wlock(&ktls_backends_lock);
247         printf("KTLS: Registering crypto method %s with prio %d\n",
248                be->name, be->prio);
249         if (LIST_EMPTY(&ktls_backends)) {
250                 LIST_INSERT_HEAD(&ktls_backends, be, next);
251         } else {
252                 LIST_FOREACH_SAFE(curr_be, &ktls_backends, next, tmp) {
253                         if (curr_be->prio < be->prio) {
254                                 LIST_INSERT_BEFORE(curr_be, be, next);
255                                 break;
256                         }
257                         if (LIST_NEXT(curr_be, next) == NULL) {
258                                 LIST_INSERT_AFTER(curr_be, be, next);
259                                 break;
260                         }
261                 }
262         }
263         rm_wunlock(&ktls_backends_lock);
264         return (0);
265 }
266
267 int
268 ktls_crypto_backend_deregister(struct ktls_crypto_backend *be)
269 {
270         struct ktls_crypto_backend *tmp;
271
272         /*
273          * Don't error if the backend isn't registered.  This permits
274          * MOD_UNLOAD handlers to use this function unconditionally.
275          */
276         rm_wlock(&ktls_backends_lock);
277         LIST_FOREACH(tmp, &ktls_backends, next) {
278                 if (tmp == be)
279                         break;
280         }
281         if (tmp == NULL) {
282                 rm_wunlock(&ktls_backends_lock);
283                 return (0);
284         }
285
286         if (!ktls_allow_unload) {
287                 rm_wunlock(&ktls_backends_lock);
288                 printf(
289                     "KTLS: Deregistering crypto method %s is not supported\n",
290                     be->name);
291                 return (EBUSY);
292         }
293
294         if (be->use_count) {
295                 rm_wunlock(&ktls_backends_lock);
296                 return (EBUSY);
297         }
298
299         LIST_REMOVE(be, next);
300         rm_wunlock(&ktls_backends_lock);
301         return (0);
302 }
303
304 #if defined(INET) || defined(INET6)
305 static u_int
306 ktls_get_cpu(struct socket *so)
307 {
308         struct inpcb *inp;
309         u_int cpuid;
310
311         inp = sotoinpcb(so);
312 #ifdef RSS
313         cpuid = rss_hash2cpuid(inp->inp_flowid, inp->inp_flowtype);
314         if (cpuid != NETISR_CPUID_NONE)
315                 return (cpuid);
316 #endif
317         /*
318          * Just use the flowid to shard connections in a repeatable
319          * fashion.  Note that some crypto backends rely on the
320          * serialization provided by having the same connection use
321          * the same queue.
322          */
323         cpuid = ktls_cpuid_lookup[inp->inp_flowid % ktls_number_threads];
324         return (cpuid);
325 }
326 #endif
327
328 static void
329 ktls_init(void *dummy __unused)
330 {
331         struct thread *td;
332         struct pcpu *pc;
333         cpuset_t mask;
334         int error, i;
335
336         ktls_tasks_active = counter_u64_alloc(M_WAITOK);
337         ktls_cnt_on = counter_u64_alloc(M_WAITOK);
338         ktls_offload_total = counter_u64_alloc(M_WAITOK);
339         ktls_offload_enable_calls = counter_u64_alloc(M_WAITOK);
340         ktls_offload_active = counter_u64_alloc(M_WAITOK);
341         ktls_offload_failed_crypto = counter_u64_alloc(M_WAITOK);
342         ktls_switch_to_ifnet = counter_u64_alloc(M_WAITOK);
343         ktls_switch_to_sw = counter_u64_alloc(M_WAITOK);
344         ktls_switch_failed = counter_u64_alloc(M_WAITOK);
345         ktls_sw_cbc = counter_u64_alloc(M_WAITOK);
346         ktls_sw_gcm = counter_u64_alloc(M_WAITOK);
347         ktls_ifnet_cbc = counter_u64_alloc(M_WAITOK);
348         ktls_ifnet_gcm = counter_u64_alloc(M_WAITOK);
349         ktls_ifnet_reset = counter_u64_alloc(M_WAITOK);
350         ktls_ifnet_reset_dropped = counter_u64_alloc(M_WAITOK);
351         ktls_ifnet_reset_failed = counter_u64_alloc(M_WAITOK);
352 #ifdef TCP_OFFLOAD
353         ktls_toe_cbc = counter_u64_alloc(M_WAITOK);
354         ktls_toe_gcm = counter_u64_alloc(M_WAITOK);
355 #endif
356
357         rm_init(&ktls_backends_lock, "ktls backends");
358         LIST_INIT(&ktls_backends);
359
360         ktls_wq = malloc(sizeof(*ktls_wq) * (mp_maxid + 1), M_KTLS,
361             M_WAITOK | M_ZERO);
362
363         ktls_session_zone = uma_zcreate("ktls_session",
364             sizeof(struct ktls_session),
365             NULL, NULL, NULL, NULL,
366             UMA_ALIGN_CACHE, 0);
367
368         /*
369          * Initialize the workqueues to run the TLS work.  We create a
370          * work queue for each CPU.
371          */
372         CPU_FOREACH(i) {
373                 STAILQ_INIT(&ktls_wq[i].head);
374                 mtx_init(&ktls_wq[i].mtx, "ktls work queue", NULL, MTX_DEF);
375                 error = kproc_kthread_add(ktls_work_thread, &ktls_wq[i],
376                     &ktls_proc, &td, 0, 0, "KTLS", "thr_%d", i);
377                 if (error)
378                         panic("Can't add KTLS thread %d error %d", i, error);
379
380                 /*
381                  * Bind threads to cores.  If ktls_bind_threads is >
382                  * 1, then we bind to the NUMA domain.
383                  */
384                 if (ktls_bind_threads) {
385                         if (ktls_bind_threads > 1) {
386                                 pc = pcpu_find(i);
387                                 CPU_COPY(&cpuset_domain[pc->pc_domain], &mask);
388                         } else {
389                                 CPU_SETOF(i, &mask);
390                         }
391                         error = cpuset_setthread(td->td_tid, &mask);
392                         if (error)
393                                 panic(
394                             "Unable to bind KTLS thread for CPU %d error %d",
395                                      i, error);
396                 }
397                 ktls_cpuid_lookup[ktls_number_threads] = i;
398                 ktls_number_threads++;
399         }
400         printf("KTLS: Initialized %d threads\n", ktls_number_threads);
401 }
402 SYSINIT(ktls, SI_SUB_SMP + 1, SI_ORDER_ANY, ktls_init, NULL);
403
404 #if defined(INET) || defined(INET6)
405 static int
406 ktls_create_session(struct socket *so, struct tls_enable *en,
407     struct ktls_session **tlsp)
408 {
409         struct ktls_session *tls;
410         int error;
411
412         /* Only TLS 1.0 - 1.3 are supported. */
413         if (en->tls_vmajor != TLS_MAJOR_VER_ONE)
414                 return (EINVAL);
415         if (en->tls_vminor < TLS_MINOR_VER_ZERO ||
416             en->tls_vminor > TLS_MINOR_VER_THREE)
417                 return (EINVAL);
418
419         if (en->auth_key_len < 0 || en->auth_key_len > TLS_MAX_PARAM_SIZE)
420                 return (EINVAL);
421         if (en->cipher_key_len < 0 || en->cipher_key_len > TLS_MAX_PARAM_SIZE)
422                 return (EINVAL);
423         if (en->iv_len < 0 || en->iv_len > sizeof(tls->params.iv))
424                 return (EINVAL);
425
426         /* All supported algorithms require a cipher key. */
427         if (en->cipher_key_len == 0)
428                 return (EINVAL);
429
430         /* No flags are currently supported. */
431         if (en->flags != 0)
432                 return (EINVAL);
433
434         /* Common checks for supported algorithms. */
435         switch (en->cipher_algorithm) {
436         case CRYPTO_AES_NIST_GCM_16:
437                 /*
438                  * auth_algorithm isn't used, but permit GMAC values
439                  * for compatibility.
440                  */
441                 switch (en->auth_algorithm) {
442                 case 0:
443 #ifdef COMPAT_FREEBSD12
444                 /* XXX: Really 13.0-current COMPAT. */
445                 case CRYPTO_AES_128_NIST_GMAC:
446                 case CRYPTO_AES_192_NIST_GMAC:
447                 case CRYPTO_AES_256_NIST_GMAC:
448 #endif
449                         break;
450                 default:
451                         return (EINVAL);
452                 }
453                 if (en->auth_key_len != 0)
454                         return (EINVAL);
455                 if ((en->tls_vminor == TLS_MINOR_VER_TWO &&
456                         en->iv_len != TLS_AEAD_GCM_LEN) ||
457                     (en->tls_vminor == TLS_MINOR_VER_THREE &&
458                         en->iv_len != TLS_1_3_GCM_IV_LEN))
459                         return (EINVAL);
460                 break;
461         case CRYPTO_AES_CBC:
462                 switch (en->auth_algorithm) {
463                 case CRYPTO_SHA1_HMAC:
464                         /*
465                          * TLS 1.0 requires an implicit IV.  TLS 1.1+
466                          * all use explicit IVs.
467                          */
468                         if (en->tls_vminor == TLS_MINOR_VER_ZERO) {
469                                 if (en->iv_len != TLS_CBC_IMPLICIT_IV_LEN)
470                                         return (EINVAL);
471                                 break;
472                         }
473
474                         /* FALLTHROUGH */
475                 case CRYPTO_SHA2_256_HMAC:
476                 case CRYPTO_SHA2_384_HMAC:
477                         /* Ignore any supplied IV. */
478                         en->iv_len = 0;
479                         break;
480                 default:
481                         return (EINVAL);
482                 }
483                 if (en->auth_key_len == 0)
484                         return (EINVAL);
485                 break;
486         default:
487                 return (EINVAL);
488         }
489
490         tls = uma_zalloc(ktls_session_zone, M_WAITOK | M_ZERO);
491
492         counter_u64_add(ktls_offload_active, 1);
493
494         refcount_init(&tls->refcount, 1);
495         TASK_INIT(&tls->reset_tag_task, 0, ktls_reset_send_tag, tls);
496
497         tls->wq_index = ktls_get_cpu(so);
498
499         tls->params.cipher_algorithm = en->cipher_algorithm;
500         tls->params.auth_algorithm = en->auth_algorithm;
501         tls->params.tls_vmajor = en->tls_vmajor;
502         tls->params.tls_vminor = en->tls_vminor;
503         tls->params.flags = en->flags;
504         tls->params.max_frame_len = min(TLS_MAX_MSG_SIZE_V10_2, ktls_maxlen);
505
506         /* Set the header and trailer lengths. */
507         tls->params.tls_hlen = sizeof(struct tls_record_layer);
508         switch (en->cipher_algorithm) {
509         case CRYPTO_AES_NIST_GCM_16:
510                 /*
511                  * TLS 1.2 uses a 4 byte implicit IV with an explicit 8 byte
512                  * nonce.  TLS 1.3 uses a 12 byte implicit IV.
513                  */
514                 if (en->tls_vminor < TLS_MINOR_VER_THREE)
515                         tls->params.tls_hlen += sizeof(uint64_t);
516                 tls->params.tls_tlen = AES_GMAC_HASH_LEN;
517
518                 /*
519                  * TLS 1.3 includes optional padding which we
520                  * do not support, and also puts the "real" record
521                  * type at the end of the encrypted data.
522                  */
523                 if (en->tls_vminor == TLS_MINOR_VER_THREE)
524                         tls->params.tls_tlen += sizeof(uint8_t);
525
526                 tls->params.tls_bs = 1;
527                 break;
528         case CRYPTO_AES_CBC:
529                 switch (en->auth_algorithm) {
530                 case CRYPTO_SHA1_HMAC:
531                         if (en->tls_vminor == TLS_MINOR_VER_ZERO) {
532                                 /* Implicit IV, no nonce. */
533                         } else {
534                                 tls->params.tls_hlen += AES_BLOCK_LEN;
535                         }
536                         tls->params.tls_tlen = AES_BLOCK_LEN +
537                             SHA1_HASH_LEN;
538                         break;
539                 case CRYPTO_SHA2_256_HMAC:
540                         tls->params.tls_hlen += AES_BLOCK_LEN;
541                         tls->params.tls_tlen = AES_BLOCK_LEN +
542                             SHA2_256_HASH_LEN;
543                         break;
544                 case CRYPTO_SHA2_384_HMAC:
545                         tls->params.tls_hlen += AES_BLOCK_LEN;
546                         tls->params.tls_tlen = AES_BLOCK_LEN +
547                             SHA2_384_HASH_LEN;
548                         break;
549                 default:
550                         panic("invalid hmac");
551                 }
552                 tls->params.tls_bs = AES_BLOCK_LEN;
553                 break;
554         default:
555                 panic("invalid cipher");
556         }
557
558         KASSERT(tls->params.tls_hlen <= MBUF_PEXT_HDR_LEN,
559             ("TLS header length too long: %d", tls->params.tls_hlen));
560         KASSERT(tls->params.tls_tlen <= MBUF_PEXT_TRAIL_LEN,
561             ("TLS trailer length too long: %d", tls->params.tls_tlen));
562
563         if (en->auth_key_len != 0) {
564                 tls->params.auth_key_len = en->auth_key_len;
565                 tls->params.auth_key = malloc(en->auth_key_len, M_KTLS,
566                     M_WAITOK);
567                 error = copyin(en->auth_key, tls->params.auth_key,
568                     en->auth_key_len);
569                 if (error)
570                         goto out;
571         }
572
573         tls->params.cipher_key_len = en->cipher_key_len;
574         tls->params.cipher_key = malloc(en->cipher_key_len, M_KTLS, M_WAITOK);
575         error = copyin(en->cipher_key, tls->params.cipher_key,
576             en->cipher_key_len);
577         if (error)
578                 goto out;
579
580         /*
581          * This holds the implicit portion of the nonce for GCM and
582          * the initial implicit IV for TLS 1.0.  The explicit portions
583          * of the IV are generated in ktls_frame().
584          */
585         if (en->iv_len != 0) {
586                 tls->params.iv_len = en->iv_len;
587                 error = copyin(en->iv, tls->params.iv, en->iv_len);
588                 if (error)
589                         goto out;
590
591                 /*
592                  * For TLS 1.2, generate an 8-byte nonce as a counter
593                  * to generate unique explicit IVs.
594                  *
595                  * Store this counter in the last 8 bytes of the IV
596                  * array so that it is 8-byte aligned.
597                  */
598                 if (en->cipher_algorithm == CRYPTO_AES_NIST_GCM_16 &&
599                     en->tls_vminor == TLS_MINOR_VER_TWO)
600                         arc4rand(tls->params.iv + 8, sizeof(uint64_t), 0);
601         }
602
603         *tlsp = tls;
604         return (0);
605
606 out:
607         ktls_cleanup(tls);
608         return (error);
609 }
610
611 static struct ktls_session *
612 ktls_clone_session(struct ktls_session *tls)
613 {
614         struct ktls_session *tls_new;
615
616         tls_new = uma_zalloc(ktls_session_zone, M_WAITOK | M_ZERO);
617
618         counter_u64_add(ktls_offload_active, 1);
619
620         refcount_init(&tls_new->refcount, 1);
621
622         /* Copy fields from existing session. */
623         tls_new->params = tls->params;
624         tls_new->wq_index = tls->wq_index;
625
626         /* Deep copy keys. */
627         if (tls_new->params.auth_key != NULL) {
628                 tls_new->params.auth_key = malloc(tls->params.auth_key_len,
629                     M_KTLS, M_WAITOK);
630                 memcpy(tls_new->params.auth_key, tls->params.auth_key,
631                     tls->params.auth_key_len);
632         }
633
634         tls_new->params.cipher_key = malloc(tls->params.cipher_key_len, M_KTLS,
635             M_WAITOK);
636         memcpy(tls_new->params.cipher_key, tls->params.cipher_key,
637             tls->params.cipher_key_len);
638
639         return (tls_new);
640 }
641 #endif
642
643 static void
644 ktls_cleanup(struct ktls_session *tls)
645 {
646
647         counter_u64_add(ktls_offload_active, -1);
648         switch (tls->mode) {
649         case TCP_TLS_MODE_SW:
650                 MPASS(tls->be != NULL);
651                 switch (tls->params.cipher_algorithm) {
652                 case CRYPTO_AES_CBC:
653                         counter_u64_add(ktls_sw_cbc, -1);
654                         break;
655                 case CRYPTO_AES_NIST_GCM_16:
656                         counter_u64_add(ktls_sw_gcm, -1);
657                         break;
658                 }
659                 tls->free(tls);
660                 break;
661         case TCP_TLS_MODE_IFNET:
662                 switch (tls->params.cipher_algorithm) {
663                 case CRYPTO_AES_CBC:
664                         counter_u64_add(ktls_ifnet_cbc, -1);
665                         break;
666                 case CRYPTO_AES_NIST_GCM_16:
667                         counter_u64_add(ktls_ifnet_gcm, -1);
668                         break;
669                 }
670                 m_snd_tag_rele(tls->snd_tag);
671                 break;
672 #ifdef TCP_OFFLOAD
673         case TCP_TLS_MODE_TOE:
674                 switch (tls->params.cipher_algorithm) {
675                 case CRYPTO_AES_CBC:
676                         counter_u64_add(ktls_toe_cbc, -1);
677                         break;
678                 case CRYPTO_AES_NIST_GCM_16:
679                         counter_u64_add(ktls_toe_gcm, -1);
680                         break;
681                 }
682                 break;
683 #endif
684         }
685         if (tls->params.auth_key != NULL) {
686                 explicit_bzero(tls->params.auth_key, tls->params.auth_key_len);
687                 free(tls->params.auth_key, M_KTLS);
688                 tls->params.auth_key = NULL;
689                 tls->params.auth_key_len = 0;
690         }
691         if (tls->params.cipher_key != NULL) {
692                 explicit_bzero(tls->params.cipher_key,
693                     tls->params.cipher_key_len);
694                 free(tls->params.cipher_key, M_KTLS);
695                 tls->params.cipher_key = NULL;
696                 tls->params.cipher_key_len = 0;
697         }
698         explicit_bzero(tls->params.iv, sizeof(tls->params.iv));
699 }
700
701 #if defined(INET) || defined(INET6)
702
703 #ifdef TCP_OFFLOAD
704 static int
705 ktls_try_toe(struct socket *so, struct ktls_session *tls)
706 {
707         struct inpcb *inp;
708         struct tcpcb *tp;
709         int error;
710
711         inp = so->so_pcb;
712         INP_WLOCK(inp);
713         if (inp->inp_flags2 & INP_FREED) {
714                 INP_WUNLOCK(inp);
715                 return (ECONNRESET);
716         }
717         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
718                 INP_WUNLOCK(inp);
719                 return (ECONNRESET);
720         }
721         if (inp->inp_socket == NULL) {
722                 INP_WUNLOCK(inp);
723                 return (ECONNRESET);
724         }
725         tp = intotcpcb(inp);
726         if (tp->tod == NULL) {
727                 INP_WUNLOCK(inp);
728                 return (EOPNOTSUPP);
729         }
730
731         error = tcp_offload_alloc_tls_session(tp, tls);
732         INP_WUNLOCK(inp);
733         if (error == 0) {
734                 tls->mode = TCP_TLS_MODE_TOE;
735                 switch (tls->params.cipher_algorithm) {
736                 case CRYPTO_AES_CBC:
737                         counter_u64_add(ktls_toe_cbc, 1);
738                         break;
739                 case CRYPTO_AES_NIST_GCM_16:
740                         counter_u64_add(ktls_toe_gcm, 1);
741                         break;
742                 }
743         }
744         return (error);
745 }
746 #endif
747
748 /*
749  * Common code used when first enabling ifnet TLS on a connection or
750  * when allocating a new ifnet TLS session due to a routing change.
751  * This function allocates a new TLS send tag on whatever interface
752  * the connection is currently routed over.
753  */
754 static int
755 ktls_alloc_snd_tag(struct inpcb *inp, struct ktls_session *tls, bool force,
756     struct m_snd_tag **mstp)
757 {
758         union if_snd_tag_alloc_params params;
759         struct ifnet *ifp;
760         struct nhop_object *nh;
761         struct tcpcb *tp;
762         int error;
763
764         INP_RLOCK(inp);
765         if (inp->inp_flags2 & INP_FREED) {
766                 INP_RUNLOCK(inp);
767                 return (ECONNRESET);
768         }
769         if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
770                 INP_RUNLOCK(inp);
771                 return (ECONNRESET);
772         }
773         if (inp->inp_socket == NULL) {
774                 INP_RUNLOCK(inp);
775                 return (ECONNRESET);
776         }
777         tp = intotcpcb(inp);
778
779         /*
780          * Check administrative controls on ifnet TLS to determine if
781          * ifnet TLS should be denied.
782          *
783          * - Always permit 'force' requests.
784          * - ktls_ifnet_permitted == 0: always deny.
785          */
786         if (!force && ktls_ifnet_permitted == 0) {
787                 INP_RUNLOCK(inp);
788                 return (ENXIO);
789         }
790
791         /*
792          * XXX: Use the cached route in the inpcb to find the
793          * interface.  This should perhaps instead use
794          * rtalloc1_fib(dst, 0, 0, fibnum).  Since KTLS is only
795          * enabled after a connection has completed key negotiation in
796          * userland, the cached route will be present in practice.
797          */
798         nh = inp->inp_route.ro_nh;
799         if (nh == NULL) {
800                 INP_RUNLOCK(inp);
801                 return (ENXIO);
802         }
803         ifp = nh->nh_ifp;
804         if_ref(ifp);
805
806         params.hdr.type = IF_SND_TAG_TYPE_TLS;
807         params.hdr.flowid = inp->inp_flowid;
808         params.hdr.flowtype = inp->inp_flowtype;
809         params.hdr.numa_domain = inp->inp_numa_domain;
810         params.tls.inp = inp;
811         params.tls.tls = tls;
812         INP_RUNLOCK(inp);
813
814         if (ifp->if_snd_tag_alloc == NULL) {
815                 error = EOPNOTSUPP;
816                 goto out;
817         }
818         if ((ifp->if_capenable & IFCAP_NOMAP) == 0) {   
819                 error = EOPNOTSUPP;
820                 goto out;
821         }
822         if (inp->inp_vflag & INP_IPV6) {
823                 if ((ifp->if_capenable & IFCAP_TXTLS6) == 0) {
824                         error = EOPNOTSUPP;
825                         goto out;
826                 }
827         } else {
828                 if ((ifp->if_capenable & IFCAP_TXTLS4) == 0) {
829                         error = EOPNOTSUPP;
830                         goto out;
831                 }
832         }
833         error = ifp->if_snd_tag_alloc(ifp, &params, mstp);
834 out:
835         if_rele(ifp);
836         return (error);
837 }
838
839 static int
840 ktls_try_ifnet(struct socket *so, struct ktls_session *tls, bool force)
841 {
842         struct m_snd_tag *mst;
843         int error;
844
845         error = ktls_alloc_snd_tag(so->so_pcb, tls, force, &mst);
846         if (error == 0) {
847                 tls->mode = TCP_TLS_MODE_IFNET;
848                 tls->snd_tag = mst;
849                 switch (tls->params.cipher_algorithm) {
850                 case CRYPTO_AES_CBC:
851                         counter_u64_add(ktls_ifnet_cbc, 1);
852                         break;
853                 case CRYPTO_AES_NIST_GCM_16:
854                         counter_u64_add(ktls_ifnet_gcm, 1);
855                         break;
856                 }
857         }
858         return (error);
859 }
860
861 static int
862 ktls_try_sw(struct socket *so, struct ktls_session *tls)
863 {
864         struct rm_priotracker prio;
865         struct ktls_crypto_backend *be;
866
867         /*
868          * Choose the best software crypto backend.  Backends are
869          * stored in sorted priority order (larget value == most
870          * important at the head of the list), so this just stops on
871          * the first backend that claims the session by returning
872          * success.
873          */
874         if (ktls_allow_unload)
875                 rm_rlock(&ktls_backends_lock, &prio);
876         LIST_FOREACH(be, &ktls_backends, next) {
877                 if (be->try(so, tls) == 0)
878                         break;
879                 KASSERT(tls->cipher == NULL,
880                     ("ktls backend leaked a cipher pointer"));
881         }
882         if (be != NULL) {
883                 if (ktls_allow_unload)
884                         be->use_count++;
885                 tls->be = be;
886         }
887         if (ktls_allow_unload)
888                 rm_runlock(&ktls_backends_lock, &prio);
889         if (be == NULL)
890                 return (EOPNOTSUPP);
891         tls->mode = TCP_TLS_MODE_SW;
892         switch (tls->params.cipher_algorithm) {
893         case CRYPTO_AES_CBC:
894                 counter_u64_add(ktls_sw_cbc, 1);
895                 break;
896         case CRYPTO_AES_NIST_GCM_16:
897                 counter_u64_add(ktls_sw_gcm, 1);
898                 break;
899         }
900         return (0);
901 }
902
903 int
904 ktls_enable_tx(struct socket *so, struct tls_enable *en)
905 {
906         struct ktls_session *tls;
907         int error;
908
909         if (!ktls_offload_enable)
910                 return (ENOTSUP);
911
912         counter_u64_add(ktls_offload_enable_calls, 1);
913
914         /*
915          * This should always be true since only the TCP socket option
916          * invokes this function.
917          */
918         if (so->so_proto->pr_protocol != IPPROTO_TCP)
919                 return (EINVAL);
920
921         /*
922          * XXX: Don't overwrite existing sessions.  We should permit
923          * this to support rekeying in the future.
924          */
925         if (so->so_snd.sb_tls_info != NULL)
926                 return (EALREADY);
927
928         if (en->cipher_algorithm == CRYPTO_AES_CBC && !ktls_cbc_enable)
929                 return (ENOTSUP);
930
931         /* TLS requires ext pgs */
932         if (mb_use_ext_pgs == 0)
933                 return (ENXIO);
934
935         error = ktls_create_session(so, en, &tls);
936         if (error)
937                 return (error);
938
939         /* Prefer TOE -> ifnet TLS -> software TLS. */
940 #ifdef TCP_OFFLOAD
941         error = ktls_try_toe(so, tls);
942         if (error)
943 #endif
944                 error = ktls_try_ifnet(so, tls, false);
945         if (error)
946                 error = ktls_try_sw(so, tls);
947
948         if (error) {
949                 ktls_cleanup(tls);
950                 return (error);
951         }
952
953         error = sblock(&so->so_snd, SBL_WAIT);
954         if (error) {
955                 ktls_cleanup(tls);
956                 return (error);
957         }
958
959         SOCKBUF_LOCK(&so->so_snd);
960         so->so_snd.sb_tls_info = tls;
961         if (tls->mode != TCP_TLS_MODE_SW)
962                 so->so_snd.sb_flags |= SB_TLS_IFNET;
963         SOCKBUF_UNLOCK(&so->so_snd);
964         sbunlock(&so->so_snd);
965
966         counter_u64_add(ktls_offload_total, 1);
967
968         return (0);
969 }
970
971 int
972 ktls_get_tx_mode(struct socket *so)
973 {
974         struct ktls_session *tls;
975         struct inpcb *inp;
976         int mode;
977
978         inp = so->so_pcb;
979         INP_WLOCK_ASSERT(inp);
980         SOCKBUF_LOCK(&so->so_snd);
981         tls = so->so_snd.sb_tls_info;
982         if (tls == NULL)
983                 mode = TCP_TLS_MODE_NONE;
984         else
985                 mode = tls->mode;
986         SOCKBUF_UNLOCK(&so->so_snd);
987         return (mode);
988 }
989
990 /*
991  * Switch between SW and ifnet TLS sessions as requested.
992  */
993 int
994 ktls_set_tx_mode(struct socket *so, int mode)
995 {
996         struct ktls_session *tls, *tls_new;
997         struct inpcb *inp;
998         int error;
999
1000         switch (mode) {
1001         case TCP_TLS_MODE_SW:
1002         case TCP_TLS_MODE_IFNET:
1003                 break;
1004         default:
1005                 return (EINVAL);
1006         }
1007
1008         inp = so->so_pcb;
1009         INP_WLOCK_ASSERT(inp);
1010         SOCKBUF_LOCK(&so->so_snd);
1011         tls = so->so_snd.sb_tls_info;
1012         if (tls == NULL) {
1013                 SOCKBUF_UNLOCK(&so->so_snd);
1014                 return (0);
1015         }
1016
1017         if (tls->mode == mode) {
1018                 SOCKBUF_UNLOCK(&so->so_snd);
1019                 return (0);
1020         }
1021
1022         tls = ktls_hold(tls);
1023         SOCKBUF_UNLOCK(&so->so_snd);
1024         INP_WUNLOCK(inp);
1025
1026         tls_new = ktls_clone_session(tls);
1027
1028         if (mode == TCP_TLS_MODE_IFNET)
1029                 error = ktls_try_ifnet(so, tls_new, true);
1030         else
1031                 error = ktls_try_sw(so, tls_new);
1032         if (error) {
1033                 counter_u64_add(ktls_switch_failed, 1);
1034                 ktls_free(tls_new);
1035                 ktls_free(tls);
1036                 INP_WLOCK(inp);
1037                 return (error);
1038         }
1039
1040         error = sblock(&so->so_snd, SBL_WAIT);
1041         if (error) {
1042                 counter_u64_add(ktls_switch_failed, 1);
1043                 ktls_free(tls_new);
1044                 ktls_free(tls);
1045                 INP_WLOCK(inp);
1046                 return (error);
1047         }
1048
1049         /*
1050          * If we raced with another session change, keep the existing
1051          * session.
1052          */
1053         if (tls != so->so_snd.sb_tls_info) {
1054                 counter_u64_add(ktls_switch_failed, 1);
1055                 sbunlock(&so->so_snd);
1056                 ktls_free(tls_new);
1057                 ktls_free(tls);
1058                 INP_WLOCK(inp);
1059                 return (EBUSY);
1060         }
1061
1062         SOCKBUF_LOCK(&so->so_snd);
1063         so->so_snd.sb_tls_info = tls_new;
1064         if (tls_new->mode != TCP_TLS_MODE_SW)
1065                 so->so_snd.sb_flags |= SB_TLS_IFNET;
1066         SOCKBUF_UNLOCK(&so->so_snd);
1067         sbunlock(&so->so_snd);
1068
1069         /*
1070          * Drop two references on 'tls'.  The first is for the
1071          * ktls_hold() above.  The second drops the reference from the
1072          * socket buffer.
1073          */
1074         KASSERT(tls->refcount >= 2, ("too few references on old session"));
1075         ktls_free(tls);
1076         ktls_free(tls);
1077
1078         if (mode == TCP_TLS_MODE_IFNET)
1079                 counter_u64_add(ktls_switch_to_ifnet, 1);
1080         else
1081                 counter_u64_add(ktls_switch_to_sw, 1);
1082
1083         INP_WLOCK(inp);
1084         return (0);
1085 }
1086
1087 /*
1088  * Try to allocate a new TLS send tag.  This task is scheduled when
1089  * ip_output detects a route change while trying to transmit a packet
1090  * holding a TLS record.  If a new tag is allocated, replace the tag
1091  * in the TLS session.  Subsequent packets on the connection will use
1092  * the new tag.  If a new tag cannot be allocated, drop the
1093  * connection.
1094  */
1095 static void
1096 ktls_reset_send_tag(void *context, int pending)
1097 {
1098         struct epoch_tracker et;
1099         struct ktls_session *tls;
1100         struct m_snd_tag *old, *new;
1101         struct inpcb *inp;
1102         struct tcpcb *tp;
1103         int error;
1104
1105         MPASS(pending == 1);
1106
1107         tls = context;
1108         inp = tls->inp;
1109
1110         /*
1111          * Free the old tag first before allocating a new one.
1112          * ip[6]_output_send() will treat a NULL send tag the same as
1113          * an ifp mismatch and drop packets until a new tag is
1114          * allocated.
1115          *
1116          * Write-lock the INP when changing tls->snd_tag since
1117          * ip[6]_output_send() holds a read-lock when reading the
1118          * pointer.
1119          */
1120         INP_WLOCK(inp);
1121         old = tls->snd_tag;
1122         tls->snd_tag = NULL;
1123         INP_WUNLOCK(inp);
1124         if (old != NULL)
1125                 m_snd_tag_rele(old);
1126
1127         error = ktls_alloc_snd_tag(inp, tls, true, &new);
1128
1129         if (error == 0) {
1130                 INP_WLOCK(inp);
1131                 tls->snd_tag = new;
1132                 mtx_pool_lock(mtxpool_sleep, tls);
1133                 tls->reset_pending = false;
1134                 mtx_pool_unlock(mtxpool_sleep, tls);
1135                 if (!in_pcbrele_wlocked(inp))
1136                         INP_WUNLOCK(inp);
1137
1138                 counter_u64_add(ktls_ifnet_reset, 1);
1139
1140                 /*
1141                  * XXX: Should we kick tcp_output explicitly now that
1142                  * the send tag is fixed or just rely on timers?
1143                  */
1144         } else {
1145                 NET_EPOCH_ENTER(et);
1146                 INP_WLOCK(inp);
1147                 if (!in_pcbrele_wlocked(inp)) {
1148                         if (!(inp->inp_flags & INP_TIMEWAIT) &&
1149                             !(inp->inp_flags & INP_DROPPED)) {
1150                                 tp = intotcpcb(inp);
1151                                 CURVNET_SET(tp->t_vnet);
1152                                 tp = tcp_drop(tp, ECONNABORTED);
1153                                 CURVNET_RESTORE();
1154                                 if (tp != NULL)
1155                                         INP_WUNLOCK(inp);
1156                                 counter_u64_add(ktls_ifnet_reset_dropped, 1);
1157                         } else
1158                                 INP_WUNLOCK(inp);
1159                 }
1160                 NET_EPOCH_EXIT(et);
1161
1162                 counter_u64_add(ktls_ifnet_reset_failed, 1);
1163
1164                 /*
1165                  * Leave reset_pending true to avoid future tasks while
1166                  * the socket goes away.
1167                  */
1168         }
1169
1170         ktls_free(tls);
1171 }
1172
1173 int
1174 ktls_output_eagain(struct inpcb *inp, struct ktls_session *tls)
1175 {
1176
1177         if (inp == NULL)
1178                 return (ENOBUFS);
1179
1180         INP_LOCK_ASSERT(inp);
1181
1182         /*
1183          * See if we should schedule a task to update the send tag for
1184          * this session.
1185          */
1186         mtx_pool_lock(mtxpool_sleep, tls);
1187         if (!tls->reset_pending) {
1188                 (void) ktls_hold(tls);
1189                 in_pcbref(inp);
1190                 tls->inp = inp;
1191                 tls->reset_pending = true;
1192                 taskqueue_enqueue(taskqueue_thread, &tls->reset_tag_task);
1193         }
1194         mtx_pool_unlock(mtxpool_sleep, tls);
1195         return (ENOBUFS);
1196 }
1197 #endif
1198
1199 void
1200 ktls_destroy(struct ktls_session *tls)
1201 {
1202         struct rm_priotracker prio;
1203
1204         ktls_cleanup(tls);
1205         if (tls->be != NULL && ktls_allow_unload) {
1206                 rm_rlock(&ktls_backends_lock, &prio);
1207                 tls->be->use_count--;
1208                 rm_runlock(&ktls_backends_lock, &prio);
1209         }
1210         uma_zfree(ktls_session_zone, tls);
1211 }
1212
1213 void
1214 ktls_seq(struct sockbuf *sb, struct mbuf *m)
1215 {
1216         struct mbuf_ext_pgs *pgs;
1217
1218         for (; m != NULL; m = m->m_next) {
1219                 KASSERT((m->m_flags & M_NOMAP) != 0,
1220                     ("ktls_seq: mapped mbuf %p", m));
1221
1222                 pgs = &m->m_ext_pgs;
1223                 pgs->seqno = sb->sb_tls_seqno;
1224                 sb->sb_tls_seqno++;
1225         }
1226 }
1227
1228 /*
1229  * Add TLS framing (headers and trailers) to a chain of mbufs.  Each
1230  * mbuf in the chain must be an unmapped mbuf.  The payload of the
1231  * mbuf must be populated with the payload of each TLS record.
1232  *
1233  * The record_type argument specifies the TLS record type used when
1234  * populating the TLS header.
1235  *
1236  * The enq_count argument on return is set to the number of pages of
1237  * payload data for this entire chain that need to be encrypted via SW
1238  * encryption.  The returned value should be passed to ktls_enqueue
1239  * when scheduling encryption of this chain of mbufs.
1240  */
1241 void
1242 ktls_frame(struct mbuf *top, struct ktls_session *tls, int *enq_cnt,
1243     uint8_t record_type)
1244 {
1245         struct tls_record_layer *tlshdr;
1246         struct mbuf *m;
1247         struct mbuf_ext_pgs *pgs;
1248         uint64_t *noncep;
1249         uint16_t tls_len;
1250         int maxlen;
1251
1252         maxlen = tls->params.max_frame_len;
1253         *enq_cnt = 0;
1254         for (m = top; m != NULL; m = m->m_next) {
1255                 /*
1256                  * All mbufs in the chain should be non-empty TLS
1257                  * records whose payload does not exceed the maximum
1258                  * frame length.
1259                  */
1260                 KASSERT(m->m_len <= maxlen && m->m_len > 0,
1261                     ("ktls_frame: m %p len %d\n", m, m->m_len));
1262                 /*
1263                  * TLS frames require unmapped mbufs to store session
1264                  * info.
1265                  */
1266                 KASSERT((m->m_flags & M_NOMAP) != 0,
1267                     ("ktls_frame: mapped mbuf %p (top = %p)\n", m, top));
1268
1269                 tls_len = m->m_len;
1270                 pgs = &m->m_ext_pgs;
1271
1272                 /* Save a reference to the session. */
1273                 pgs->tls = ktls_hold(tls);
1274
1275                 pgs->hdr_len = tls->params.tls_hlen;
1276                 pgs->trail_len = tls->params.tls_tlen;
1277                 if (tls->params.cipher_algorithm == CRYPTO_AES_CBC) {
1278                         int bs, delta;
1279
1280                         /*
1281                          * AES-CBC pads messages to a multiple of the
1282                          * block size.  Note that the padding is
1283                          * applied after the digest and the encryption
1284                          * is done on the "plaintext || mac || padding".
1285                          * At least one byte of padding is always
1286                          * present.
1287                          *
1288                          * Compute the final trailer length assuming
1289                          * at most one block of padding.
1290                          * tls->params.sb_tls_tlen is the maximum
1291                          * possible trailer length (padding + digest).
1292                          * delta holds the number of excess padding
1293                          * bytes if the maximum were used.  Those
1294                          * extra bytes are removed.
1295                          */
1296                         bs = tls->params.tls_bs;
1297                         delta = (tls_len + tls->params.tls_tlen) & (bs - 1);
1298                         pgs->trail_len -= delta;
1299                 }
1300                 m->m_len += pgs->hdr_len + pgs->trail_len;
1301
1302                 /* Populate the TLS header. */
1303                 tlshdr = (void *)pgs->m_epg_hdr;
1304                 tlshdr->tls_vmajor = tls->params.tls_vmajor;
1305
1306                 /*
1307                  * TLS 1.3 masquarades as TLS 1.2 with a record type
1308                  * of TLS_RLTYPE_APP.
1309                  */
1310                 if (tls->params.tls_vminor == TLS_MINOR_VER_THREE &&
1311                     tls->params.tls_vmajor == TLS_MAJOR_VER_ONE) {
1312                         tlshdr->tls_vminor = TLS_MINOR_VER_TWO;
1313                         tlshdr->tls_type = TLS_RLTYPE_APP;
1314                         /* save the real record type for later */
1315                         pgs->record_type = record_type;
1316                         pgs->m_epg_trail[0] = record_type;
1317                 } else {
1318                         tlshdr->tls_vminor = tls->params.tls_vminor;
1319                         tlshdr->tls_type = record_type;
1320                 }
1321                 tlshdr->tls_length = htons(m->m_len - sizeof(*tlshdr));
1322
1323                 /*
1324                  * Store nonces / explicit IVs after the end of the
1325                  * TLS header.
1326                  *
1327                  * For GCM with TLS 1.2, an 8 byte nonce is copied
1328                  * from the end of the IV.  The nonce is then
1329                  * incremented for use by the next record.
1330                  *
1331                  * For CBC, a random nonce is inserted for TLS 1.1+.
1332                  */
1333                 if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16 &&
1334                     tls->params.tls_vminor == TLS_MINOR_VER_TWO) {
1335                         noncep = (uint64_t *)(tls->params.iv + 8);
1336                         be64enc(tlshdr + 1, *noncep);
1337                         (*noncep)++;
1338                 } else if (tls->params.cipher_algorithm == CRYPTO_AES_CBC &&
1339                     tls->params.tls_vminor >= TLS_MINOR_VER_ONE)
1340                         arc4rand(tlshdr + 1, AES_BLOCK_LEN, 0);
1341
1342                 /*
1343                  * When using SW encryption, mark the mbuf not ready.
1344                  * It will be marked ready via sbready() after the
1345                  * record has been encrypted.
1346                  *
1347                  * When using ifnet TLS, unencrypted TLS records are
1348                  * sent down the stack to the NIC.
1349                  */
1350                 if (tls->mode == TCP_TLS_MODE_SW) {
1351                         m->m_flags |= M_NOTREADY;
1352                         pgs->nrdy = pgs->npgs;
1353                         *enq_cnt += pgs->npgs;
1354                 }
1355         }
1356 }
1357
1358 void
1359 ktls_enqueue_to_free(struct mbuf_ext_pgs *pgs)
1360 {
1361         struct ktls_wq *wq;
1362         bool running;
1363
1364         /* Mark it for freeing. */
1365         pgs->mbuf = NULL;
1366         wq = &ktls_wq[pgs->tls->wq_index];
1367         mtx_lock(&wq->mtx);
1368         STAILQ_INSERT_TAIL(&wq->head, pgs, stailq);
1369         running = wq->running;
1370         mtx_unlock(&wq->mtx);
1371         if (!running)
1372                 wakeup(wq);
1373 }
1374
1375 void
1376 ktls_enqueue(struct mbuf *m, struct socket *so, int page_count)
1377 {
1378         struct mbuf_ext_pgs *pgs;
1379         struct ktls_wq *wq;
1380         bool running;
1381
1382         KASSERT(((m->m_flags & (M_NOMAP | M_NOTREADY)) ==
1383             (M_NOMAP | M_NOTREADY)),
1384             ("ktls_enqueue: %p not unready & nomap mbuf\n", m));
1385         KASSERT(page_count != 0, ("enqueueing TLS mbuf with zero page count"));
1386
1387         pgs = &m->m_ext_pgs;
1388
1389         KASSERT(pgs->tls->mode == TCP_TLS_MODE_SW, ("!SW TLS mbuf"));
1390
1391         pgs->enc_cnt = page_count;
1392         pgs->mbuf = m;
1393
1394         /*
1395          * Save a pointer to the socket.  The caller is responsible
1396          * for taking an additional reference via soref().
1397          */
1398         pgs->so = so;
1399
1400         wq = &ktls_wq[pgs->tls->wq_index];
1401         mtx_lock(&wq->mtx);
1402         STAILQ_INSERT_TAIL(&wq->head, pgs, stailq);
1403         running = wq->running;
1404         mtx_unlock(&wq->mtx);
1405         if (!running)
1406                 wakeup(wq);
1407         counter_u64_add(ktls_cnt_on, 1);
1408 }
1409
1410 static __noinline void
1411 ktls_encrypt(struct mbuf_ext_pgs *pgs)
1412 {
1413         struct ktls_session *tls;
1414         struct socket *so;
1415         struct mbuf *m, *top;
1416         vm_paddr_t parray[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
1417         struct iovec src_iov[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
1418         struct iovec dst_iov[1 + btoc(TLS_MAX_MSG_SIZE_V10_2)];
1419         vm_page_t pg;
1420         int error, i, len, npages, off, total_pages;
1421         bool is_anon;
1422
1423         so = pgs->so;
1424         tls = pgs->tls;
1425         top = pgs->mbuf;
1426         KASSERT(tls != NULL, ("tls = NULL, top = %p, pgs = %p\n", top, pgs));
1427         KASSERT(so != NULL, ("so = NULL, top = %p, pgs = %p\n", top, pgs));
1428 #ifdef INVARIANTS
1429         pgs->so = NULL;
1430         pgs->mbuf = NULL;
1431 #endif
1432         total_pages = pgs->enc_cnt;
1433         npages = 0;
1434
1435         /*
1436          * Encrypt the TLS records in the chain of mbufs starting with
1437          * 'top'.  'total_pages' gives us a total count of pages and is
1438          * used to know when we have finished encrypting the TLS
1439          * records originally queued with 'top'.
1440          *
1441          * NB: These mbufs are queued in the socket buffer and
1442          * 'm_next' is traversing the mbufs in the socket buffer.  The
1443          * socket buffer lock is not held while traversing this chain.
1444          * Since the mbufs are all marked M_NOTREADY their 'm_next'
1445          * pointers should be stable.  However, the 'm_next' of the
1446          * last mbuf encrypted is not necessarily NULL.  It can point
1447          * to other mbufs appended while 'top' was on the TLS work
1448          * queue.
1449          *
1450          * Each mbuf holds an entire TLS record.
1451          */
1452         error = 0;
1453         for (m = top; npages != total_pages; m = m->m_next) {
1454                 pgs = &m->m_ext_pgs;
1455
1456                 KASSERT(pgs->tls == tls,
1457                     ("different TLS sessions in a single mbuf chain: %p vs %p",
1458                     tls, pgs->tls));
1459                 KASSERT((m->m_flags & (M_NOMAP | M_NOTREADY)) ==
1460                     (M_NOMAP | M_NOTREADY),
1461                     ("%p not unready & nomap mbuf (top = %p)\n", m, top));
1462                 KASSERT(npages + pgs->npgs <= total_pages,
1463                     ("page count mismatch: top %p, total_pages %d, m %p", top,
1464                     total_pages, m));
1465
1466                 /*
1467                  * Generate source and destination ivoecs to pass to
1468                  * the SW encryption backend.  For writable mbufs, the
1469                  * destination iovec is a copy of the source and
1470                  * encryption is done in place.  For file-backed mbufs
1471                  * (from sendfile), anonymous wired pages are
1472                  * allocated and assigned to the destination iovec.
1473                  */
1474                 is_anon = (pgs->flags & MBUF_PEXT_FLAG_ANON) != 0;
1475
1476                 off = pgs->first_pg_off;
1477                 for (i = 0; i < pgs->npgs; i++, off = 0) {
1478                         len = mbuf_ext_pg_len(pgs, i, off);
1479                         src_iov[i].iov_len = len;
1480                         src_iov[i].iov_base =
1481                             (char *)(void *)PHYS_TO_DMAP(pgs->m_epg_pa[i]) +
1482                                 off;
1483
1484                         if (is_anon) {
1485                                 dst_iov[i].iov_base = src_iov[i].iov_base;
1486                                 dst_iov[i].iov_len = src_iov[i].iov_len;
1487                                 continue;
1488                         }
1489 retry_page:
1490                         pg = vm_page_alloc(NULL, 0, VM_ALLOC_NORMAL |
1491                             VM_ALLOC_NOOBJ | VM_ALLOC_NODUMP | VM_ALLOC_WIRED);
1492                         if (pg == NULL) {
1493                                 vm_wait(NULL);
1494                                 goto retry_page;
1495                         }
1496                         parray[i] = VM_PAGE_TO_PHYS(pg);
1497                         dst_iov[i].iov_base =
1498                             (char *)(void *)PHYS_TO_DMAP(parray[i]) + off;
1499                         dst_iov[i].iov_len = len;
1500                 }
1501
1502                 npages += i;
1503
1504                 error = (*tls->sw_encrypt)(tls,
1505                     (const struct tls_record_layer *)pgs->m_epg_hdr,
1506                     pgs->m_epg_trail, src_iov, dst_iov, i, pgs->seqno,
1507                     pgs->record_type);
1508                 if (error) {
1509                         counter_u64_add(ktls_offload_failed_crypto, 1);
1510                         break;
1511                 }
1512
1513                 /*
1514                  * For file-backed mbufs, release the file-backed
1515                  * pages and replace them in the ext_pgs array with
1516                  * the anonymous wired pages allocated above.
1517                  */
1518                 if (!is_anon) {
1519                         /* Free the old pages. */
1520                         m->m_ext.ext_free(m);
1521
1522                         /* Replace them with the new pages. */
1523                         for (i = 0; i < pgs->npgs; i++)
1524                                 pgs->m_epg_pa[i] = parray[i];
1525
1526                         /* Use the basic free routine. */
1527                         m->m_ext.ext_free = mb_free_mext_pgs;
1528
1529                         /* Pages are now writable. */
1530                         pgs->flags |= MBUF_PEXT_FLAG_ANON;
1531                 }
1532
1533                 /*
1534                  * Drop a reference to the session now that it is no
1535                  * longer needed.  Existing code depends on encrypted
1536                  * records having no associated session vs
1537                  * yet-to-be-encrypted records having an associated
1538                  * session.
1539                  */
1540                 pgs->tls = NULL;
1541                 ktls_free(tls);
1542         }
1543
1544         CURVNET_SET(so->so_vnet);
1545         if (error == 0) {
1546                 (void)(*so->so_proto->pr_usrreqs->pru_ready)(so, top, npages);
1547         } else {
1548                 so->so_proto->pr_usrreqs->pru_abort(so);
1549                 so->so_error = EIO;
1550                 mb_free_notready(top, total_pages);
1551         }
1552
1553         SOCK_LOCK(so);
1554         sorele(so);
1555         CURVNET_RESTORE();
1556 }
1557
1558 static void
1559 ktls_work_thread(void *ctx)
1560 {
1561         struct ktls_wq *wq = ctx;
1562         struct mbuf_ext_pgs *p, *n;
1563         struct ktls_session *tls;
1564         struct mbuf *m;
1565         STAILQ_HEAD(, mbuf_ext_pgs) local_head;
1566
1567 #if defined(__aarch64__) || defined(__amd64__) || defined(__i386__)
1568         fpu_kern_thread(0);
1569 #endif
1570         for (;;) {
1571                 mtx_lock(&wq->mtx);
1572                 while (STAILQ_EMPTY(&wq->head)) {
1573                         wq->running = false;
1574                         mtx_sleep(wq, &wq->mtx, 0, "-", 0);
1575                         wq->running = true;
1576                 }
1577
1578                 STAILQ_INIT(&local_head);
1579                 STAILQ_CONCAT(&local_head, &wq->head);
1580                 mtx_unlock(&wq->mtx);
1581
1582                 STAILQ_FOREACH_SAFE(p, &local_head, stailq, n) {
1583                         if (p->mbuf != NULL) {
1584                                 ktls_encrypt(p);
1585                                 counter_u64_add(ktls_cnt_on, -1);
1586                         } else {
1587                                 tls = p->tls;
1588                                 ktls_free(tls);
1589                                 m = __containerof(p, struct mbuf, m_ext_pgs);
1590                                 uma_zfree(zone_mbuf, m);
1591                         }
1592                 }
1593         }
1594 }