xref: /freebsd/sys/kern/uipc_ktls.c (revision 9a6e9d7799235d3e122bcc8065e865ae265a6ce2)
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_kern_tls.h"
32 #include "opt_ratelimit.h"
33 #include "opt_rss.h"
34 
35 #include <sys/param.h>
36 #include <sys/kernel.h>
37 #include <sys/domainset.h>
38 #include <sys/endian.h>
39 #include <sys/ktls.h>
40 #include <sys/lock.h>
41 #include <sys/mbuf.h>
42 #include <sys/mutex.h>
43 #include <sys/rmlock.h>
44 #include <sys/proc.h>
45 #include <sys/protosw.h>
46 #include <sys/refcount.h>
47 #include <sys/smp.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/sysctl.h>
51 #include <sys/taskqueue.h>
52 #include <sys/kthread.h>
53 #include <sys/uio.h>
54 #include <sys/vmmeter.h>
55 #if defined(__aarch64__) || defined(__amd64__) || defined(__i386__)
56 #include <machine/pcb.h>
57 #endif
58 #include <machine/vmparam.h>
59 #include <net/if.h>
60 #include <net/if_var.h>
61 #ifdef RSS
62 #include <net/netisr.h>
63 #include <net/rss_config.h>
64 #endif
65 #include <net/route.h>
66 #include <net/route/nhop.h>
67 #include <netinet/in.h>
68 #include <netinet/in_pcb.h>
69 #include <netinet/tcp_var.h>
70 #ifdef TCP_OFFLOAD
71 #include <netinet/tcp_offload.h>
72 #endif
73 #include <opencrypto/cryptodev.h>
74 #include <opencrypto/ktls.h>
75 #include <vm/vm.h>
76 #include <vm/vm_pageout.h>
77 #include <vm/vm_page.h>
78 #include <vm/vm_pagequeue.h>
79 
80 struct ktls_wq {
81 	struct mtx	mtx;
82 	STAILQ_HEAD(, mbuf) m_head;
83 	STAILQ_HEAD(, socket) so_head;
84 	bool		running;
85 	int		lastallocfail;
86 } __aligned(CACHE_LINE_SIZE);
87 
88 struct ktls_reclaim_thread {
89 	uint64_t wakeups;
90 	uint64_t reclaims;
91 	struct thread *td;
92 	int running;
93 };
94 
95 struct ktls_domain_info {
96 	int count;
97 	int cpu[MAXCPU];
98 	struct ktls_reclaim_thread reclaim_td;
99 };
100 
101 struct ktls_domain_info ktls_domains[MAXMEMDOM];
102 static struct ktls_wq *ktls_wq;
103 static struct proc *ktls_proc;
104 static uma_zone_t ktls_session_zone;
105 static uma_zone_t ktls_buffer_zone;
106 static uint16_t ktls_cpuid_lookup[MAXCPU];
107 static int ktls_init_state;
108 static struct sx ktls_init_lock;
109 SX_SYSINIT(ktls_init_lock, &ktls_init_lock, "ktls init");
110 
111 SYSCTL_NODE(_kern_ipc, OID_AUTO, tls, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
112     "Kernel TLS offload");
113 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, stats, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
114     "Kernel TLS offload stats");
115 
116 #ifdef RSS
117 static int ktls_bind_threads = 1;
118 #else
119 static int ktls_bind_threads;
120 #endif
121 SYSCTL_INT(_kern_ipc_tls, OID_AUTO, bind_threads, CTLFLAG_RDTUN,
122     &ktls_bind_threads, 0,
123     "Bind crypto threads to cores (1) or cores and domains (2) at boot");
124 
125 static u_int ktls_maxlen = 16384;
126 SYSCTL_UINT(_kern_ipc_tls, OID_AUTO, maxlen, CTLFLAG_RDTUN,
127     &ktls_maxlen, 0, "Maximum TLS record size");
128 
129 static int ktls_number_threads;
130 SYSCTL_INT(_kern_ipc_tls_stats, OID_AUTO, threads, CTLFLAG_RD,
131     &ktls_number_threads, 0,
132     "Number of TLS threads in thread-pool");
133 
134 unsigned int ktls_ifnet_max_rexmit_pct = 2;
135 SYSCTL_UINT(_kern_ipc_tls, OID_AUTO, ifnet_max_rexmit_pct, CTLFLAG_RWTUN,
136     &ktls_ifnet_max_rexmit_pct, 2,
137     "Max percent bytes retransmitted before ifnet TLS is disabled");
138 
139 static bool ktls_offload_enable = true;
140 SYSCTL_BOOL(_kern_ipc_tls, OID_AUTO, enable, CTLFLAG_RWTUN,
141     &ktls_offload_enable, 0,
142     "Enable support for kernel TLS offload");
143 
144 static bool ktls_cbc_enable = true;
145 SYSCTL_BOOL(_kern_ipc_tls, OID_AUTO, cbc_enable, CTLFLAG_RWTUN,
146     &ktls_cbc_enable, 1,
147     "Enable support of AES-CBC crypto for kernel TLS");
148 
149 static bool ktls_sw_buffer_cache = true;
150 SYSCTL_BOOL(_kern_ipc_tls, OID_AUTO, sw_buffer_cache, CTLFLAG_RDTUN,
151     &ktls_sw_buffer_cache, 1,
152     "Enable caching of output buffers for SW encryption");
153 
154 static int ktls_max_reclaim = 1024;
155 SYSCTL_INT(_kern_ipc_tls, OID_AUTO, max_reclaim, CTLFLAG_RWTUN,
156     &ktls_max_reclaim, 128,
157     "Max number of 16k buffers to reclaim in thread context");
158 
159 static COUNTER_U64_DEFINE_EARLY(ktls_tasks_active);
160 SYSCTL_COUNTER_U64(_kern_ipc_tls, OID_AUTO, tasks_active, CTLFLAG_RD,
161     &ktls_tasks_active, "Number of active tasks");
162 
163 static COUNTER_U64_DEFINE_EARLY(ktls_cnt_tx_pending);
164 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, sw_tx_pending, CTLFLAG_RD,
165     &ktls_cnt_tx_pending,
166     "Number of TLS 1.0 records waiting for earlier TLS records");
167 
168 static COUNTER_U64_DEFINE_EARLY(ktls_cnt_tx_queued);
169 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, sw_tx_inqueue, CTLFLAG_RD,
170     &ktls_cnt_tx_queued,
171     "Number of TLS records in queue to tasks for SW encryption");
172 
173 static COUNTER_U64_DEFINE_EARLY(ktls_cnt_rx_queued);
174 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, sw_rx_inqueue, CTLFLAG_RD,
175     &ktls_cnt_rx_queued,
176     "Number of TLS sockets in queue to tasks for SW decryption");
177 
178 static COUNTER_U64_DEFINE_EARLY(ktls_offload_total);
179 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, offload_total,
180     CTLFLAG_RD, &ktls_offload_total,
181     "Total successful TLS setups (parameters set)");
182 
183 static COUNTER_U64_DEFINE_EARLY(ktls_offload_enable_calls);
184 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, enable_calls,
185     CTLFLAG_RD, &ktls_offload_enable_calls,
186     "Total number of TLS enable calls made");
187 
188 static COUNTER_U64_DEFINE_EARLY(ktls_offload_active);
189 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, active, CTLFLAG_RD,
190     &ktls_offload_active, "Total Active TLS sessions");
191 
192 static COUNTER_U64_DEFINE_EARLY(ktls_offload_corrupted_records);
193 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, corrupted_records, CTLFLAG_RD,
194     &ktls_offload_corrupted_records, "Total corrupted TLS records received");
195 
196 static COUNTER_U64_DEFINE_EARLY(ktls_offload_failed_crypto);
197 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, failed_crypto, CTLFLAG_RD,
198     &ktls_offload_failed_crypto, "Total TLS crypto failures");
199 
200 static COUNTER_U64_DEFINE_EARLY(ktls_switch_to_ifnet);
201 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_to_ifnet, CTLFLAG_RD,
202     &ktls_switch_to_ifnet, "TLS sessions switched from SW to ifnet");
203 
204 static COUNTER_U64_DEFINE_EARLY(ktls_switch_to_sw);
205 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_to_sw, CTLFLAG_RD,
206     &ktls_switch_to_sw, "TLS sessions switched from ifnet to SW");
207 
208 static COUNTER_U64_DEFINE_EARLY(ktls_switch_failed);
209 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, switch_failed, CTLFLAG_RD,
210     &ktls_switch_failed, "TLS sessions unable to switch between SW and ifnet");
211 
212 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_disable_fail);
213 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, ifnet_disable_failed, CTLFLAG_RD,
214     &ktls_ifnet_disable_fail, "TLS sessions unable to switch to SW from ifnet");
215 
216 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_disable_ok);
217 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, ifnet_disable_ok, CTLFLAG_RD,
218     &ktls_ifnet_disable_ok, "TLS sessions able to switch to SW from ifnet");
219 
220 static COUNTER_U64_DEFINE_EARLY(ktls_destroy_task);
221 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats, OID_AUTO, destroy_task, CTLFLAG_RD,
222     &ktls_destroy_task,
223     "Number of times ktls session was destroyed via taskqueue");
224 
225 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, sw, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
226     "Software TLS session stats");
227 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, ifnet, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
228     "Hardware (ifnet) TLS session stats");
229 #ifdef TCP_OFFLOAD
230 SYSCTL_NODE(_kern_ipc_tls, OID_AUTO, toe, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
231     "TOE TLS session stats");
232 #endif
233 
234 static COUNTER_U64_DEFINE_EARLY(ktls_sw_cbc);
235 SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, cbc, CTLFLAG_RD, &ktls_sw_cbc,
236     "Active number of software TLS sessions using AES-CBC");
237 
238 static COUNTER_U64_DEFINE_EARLY(ktls_sw_gcm);
239 SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, gcm, CTLFLAG_RD, &ktls_sw_gcm,
240     "Active number of software TLS sessions using AES-GCM");
241 
242 static COUNTER_U64_DEFINE_EARLY(ktls_sw_chacha20);
243 SYSCTL_COUNTER_U64(_kern_ipc_tls_sw, OID_AUTO, chacha20, CTLFLAG_RD,
244     &ktls_sw_chacha20,
245     "Active number of software TLS sessions using Chacha20-Poly1305");
246 
247 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_cbc);
248 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, cbc, CTLFLAG_RD,
249     &ktls_ifnet_cbc,
250     "Active number of ifnet TLS sessions using AES-CBC");
251 
252 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_gcm);
253 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, gcm, CTLFLAG_RD,
254     &ktls_ifnet_gcm,
255     "Active number of ifnet TLS sessions using AES-GCM");
256 
257 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_chacha20);
258 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, chacha20, CTLFLAG_RD,
259     &ktls_ifnet_chacha20,
260     "Active number of ifnet TLS sessions using Chacha20-Poly1305");
261 
262 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_reset);
263 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset, CTLFLAG_RD,
264     &ktls_ifnet_reset, "TLS sessions updated to a new ifnet send tag");
265 
266 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_reset_dropped);
267 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset_dropped, CTLFLAG_RD,
268     &ktls_ifnet_reset_dropped,
269     "TLS sessions dropped after failing to update ifnet send tag");
270 
271 static COUNTER_U64_DEFINE_EARLY(ktls_ifnet_reset_failed);
272 SYSCTL_COUNTER_U64(_kern_ipc_tls_ifnet, OID_AUTO, reset_failed, CTLFLAG_RD,
273     &ktls_ifnet_reset_failed,
274     "TLS sessions that failed to allocate a new ifnet send tag");
275 
276 static int ktls_ifnet_permitted = 1;
277 SYSCTL_UINT(_kern_ipc_tls_ifnet, OID_AUTO, permitted, CTLFLAG_RWTUN,
278     &ktls_ifnet_permitted, 1,
279     "Whether to permit hardware (ifnet) TLS sessions");
280 
281 #ifdef TCP_OFFLOAD
282 static COUNTER_U64_DEFINE_EARLY(ktls_toe_cbc);
283 SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, cbc, CTLFLAG_RD,
284     &ktls_toe_cbc,
285     "Active number of TOE TLS sessions using AES-CBC");
286 
287 static COUNTER_U64_DEFINE_EARLY(ktls_toe_gcm);
288 SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, gcm, CTLFLAG_RD,
289     &ktls_toe_gcm,
290     "Active number of TOE TLS sessions using AES-GCM");
291 
292 static COUNTER_U64_DEFINE_EARLY(ktls_toe_chacha20);
293 SYSCTL_COUNTER_U64(_kern_ipc_tls_toe, OID_AUTO, chacha20, CTLFLAG_RD,
294     &ktls_toe_chacha20,
295     "Active number of TOE TLS sessions using Chacha20-Poly1305");
296 #endif
297 
298 static MALLOC_DEFINE(M_KTLS, "ktls", "Kernel TLS");
299 
300 static void ktls_reclaim_thread(void *ctx);
301 static void ktls_reset_receive_tag(void *context, int pending);
302 static void ktls_reset_send_tag(void *context, int pending);
303 static void ktls_work_thread(void *ctx);
304 
305 int
ktls_copyin_tls_enable(struct sockopt * sopt,struct tls_enable * tls)306 ktls_copyin_tls_enable(struct sockopt *sopt, struct tls_enable *tls)
307 {
308 	struct tls_enable_v0 tls_v0;
309 	int error;
310 	uint8_t *cipher_key = NULL, *iv = NULL, *auth_key = NULL;
311 
312 	if (sopt->sopt_valsize == sizeof(tls_v0)) {
313 		error = sooptcopyin(sopt, &tls_v0, sizeof(tls_v0), sizeof(tls_v0));
314 		if (error != 0)
315 			goto done;
316 		memset(tls, 0, sizeof(*tls));
317 		tls->cipher_key = tls_v0.cipher_key;
318 		tls->iv = tls_v0.iv;
319 		tls->auth_key = tls_v0.auth_key;
320 		tls->cipher_algorithm = tls_v0.cipher_algorithm;
321 		tls->cipher_key_len = tls_v0.cipher_key_len;
322 		tls->iv_len = tls_v0.iv_len;
323 		tls->auth_algorithm = tls_v0.auth_algorithm;
324 		tls->auth_key_len = tls_v0.auth_key_len;
325 		tls->flags = tls_v0.flags;
326 		tls->tls_vmajor = tls_v0.tls_vmajor;
327 		tls->tls_vminor = tls_v0.tls_vminor;
328 	} else
329 		error = sooptcopyin(sopt, tls, sizeof(*tls), sizeof(*tls));
330 
331 	if (error != 0)
332 		return (error);
333 
334 	if (tls->cipher_key_len < 0 || tls->cipher_key_len > TLS_MAX_PARAM_SIZE)
335 		return (EINVAL);
336 	if (tls->iv_len < 0 || tls->iv_len > sizeof(((struct ktls_session *)NULL)->params.iv))
337 		return (EINVAL);
338 	if (tls->auth_key_len < 0 || tls->auth_key_len > TLS_MAX_PARAM_SIZE)
339 		return (EINVAL);
340 
341 	/* All supported algorithms require a cipher key. */
342 	if (tls->cipher_key_len == 0)
343 		return (EINVAL);
344 
345 	/*
346 	 * Now do a deep copy of the variable-length arrays in the struct, so that
347 	 * subsequent consumers of it can reliably assume kernel memory. This
348 	 * requires doing our own allocations, which we will free in the
349 	 * error paths so that our caller need only worry about outstanding
350 	 * allocations existing on successful return.
351 	 */
352 	if (tls->cipher_key_len != 0) {
353 		cipher_key = malloc(tls->cipher_key_len, M_KTLS, M_WAITOK);
354 		if (sopt->sopt_td != NULL) {
355 			error = copyin(tls->cipher_key, cipher_key, tls->cipher_key_len);
356 			if (error != 0)
357 				goto done;
358 		} else {
359 			bcopy(tls->cipher_key, cipher_key, tls->cipher_key_len);
360 		}
361 	}
362 	if (tls->iv_len != 0) {
363 		iv = malloc(tls->iv_len, M_KTLS, M_WAITOK);
364 		if (sopt->sopt_td != NULL) {
365 			error = copyin(tls->iv, iv, tls->iv_len);
366 			if (error != 0)
367 				goto done;
368 		} else {
369 			bcopy(tls->iv, iv, tls->iv_len);
370 		}
371 	}
372 	if (tls->auth_key_len != 0) {
373 		auth_key = malloc(tls->auth_key_len, M_KTLS, M_WAITOK);
374 		if (sopt->sopt_td != NULL) {
375 			error = copyin(tls->auth_key, auth_key, tls->auth_key_len);
376 			if (error != 0)
377 				goto done;
378 		} else {
379 			bcopy(tls->auth_key, auth_key, tls->auth_key_len);
380 		}
381 	}
382 	tls->cipher_key = cipher_key;
383 	tls->iv = iv;
384 	tls->auth_key = auth_key;
385 
386 done:
387 	if (error != 0) {
388 		zfree(cipher_key, M_KTLS);
389 		zfree(iv, M_KTLS);
390 		zfree(auth_key, M_KTLS);
391 	}
392 
393 	return (error);
394 }
395 
396 void
ktls_cleanup_tls_enable(struct tls_enable * tls)397 ktls_cleanup_tls_enable(struct tls_enable *tls)
398 {
399 	zfree(__DECONST(void *, tls->cipher_key), M_KTLS);
400 	zfree(__DECONST(void *, tls->iv), M_KTLS);
401 	zfree(__DECONST(void *, tls->auth_key), M_KTLS);
402 }
403 
404 static u_int
ktls_get_cpu(struct socket * so)405 ktls_get_cpu(struct socket *so)
406 {
407 	struct inpcb *inp;
408 #ifdef NUMA
409 	struct ktls_domain_info *di;
410 #endif
411 	u_int cpuid;
412 
413 	inp = sotoinpcb(so);
414 #ifdef RSS
415 	cpuid = rss_hash2cpuid(inp->inp_flowid, inp->inp_flowtype);
416 	if (cpuid != NETISR_CPUID_NONE)
417 		return (cpuid);
418 #endif
419 	/*
420 	 * Just use the flowid to shard connections in a repeatable
421 	 * fashion.  Note that TLS 1.0 sessions rely on the
422 	 * serialization provided by having the same connection use
423 	 * the same queue.
424 	 */
425 #ifdef NUMA
426 	if (ktls_bind_threads > 1 && inp->inp_numa_domain != M_NODOM) {
427 		di = &ktls_domains[inp->inp_numa_domain];
428 		cpuid = di->cpu[inp->inp_flowid % di->count];
429 	} else
430 #endif
431 		cpuid = ktls_cpuid_lookup[inp->inp_flowid % ktls_number_threads];
432 	return (cpuid);
433 }
434 
435 static int
ktls_buffer_import(void * arg,void ** store,int count,int domain,int flags)436 ktls_buffer_import(void *arg, void **store, int count, int domain, int flags)
437 {
438 	vm_page_t m;
439 	int i, req;
440 
441 	KASSERT((ktls_maxlen & PAGE_MASK) == 0,
442 	    ("%s: ktls max length %d is not page size-aligned",
443 	    __func__, ktls_maxlen));
444 
445 	req = VM_ALLOC_WIRED | VM_ALLOC_NODUMP | malloc2vm_flags(flags);
446 	for (i = 0; i < count; i++) {
447 		m = vm_page_alloc_noobj_contig_domain(domain, req,
448 		    atop(ktls_maxlen), 0, ~0ul, PAGE_SIZE, 0,
449 		    VM_MEMATTR_DEFAULT);
450 		if (m == NULL)
451 			break;
452 		store[i] = VM_PAGE_TO_DMAP(m);
453 	}
454 	return (i);
455 }
456 
457 static void
ktls_buffer_release(void * arg __unused,void ** store,int count)458 ktls_buffer_release(void *arg __unused, void **store, int count)
459 {
460 	vm_page_t m;
461 	int i, j;
462 
463 	for (i = 0; i < count; i++) {
464 		m = DMAP_TO_VM_PAGE(store[i]);
465 		for (j = 0; j < atop(ktls_maxlen); j++) {
466 			(void)vm_page_unwire_noq(m + j);
467 			vm_page_free(m + j);
468 		}
469 	}
470 }
471 
472 static void
ktls_free_mext_contig(struct mbuf * m)473 ktls_free_mext_contig(struct mbuf *m)
474 {
475 	M_ASSERTEXTPG(m);
476 	uma_zfree(ktls_buffer_zone, PHYS_TO_DMAP(m->m_epg_pa[0]));
477 }
478 
479 static int
ktls_init(void)480 ktls_init(void)
481 {
482 	struct thread *td;
483 	struct pcpu *pc;
484 	int count, domain, error, i;
485 
486 	ktls_wq = malloc(sizeof(*ktls_wq) * (mp_maxid + 1), M_KTLS,
487 	    M_WAITOK | M_ZERO);
488 
489 	ktls_session_zone = uma_zcreate("ktls_session",
490 	    sizeof(struct ktls_session),
491 	    NULL, NULL, NULL, NULL,
492 	    UMA_ALIGN_CACHE, 0);
493 
494 	if (ktls_sw_buffer_cache) {
495 		ktls_buffer_zone = uma_zcache_create("ktls_buffers",
496 		    roundup2(ktls_maxlen, PAGE_SIZE), NULL, NULL, NULL, NULL,
497 		    ktls_buffer_import, ktls_buffer_release, NULL,
498 		    UMA_ZONE_FIRSTTOUCH | UMA_ZONE_NOTRIM);
499 	}
500 
501 	/*
502 	 * Initialize the workqueues to run the TLS work.  We create a
503 	 * work queue for each CPU.
504 	 */
505 	CPU_FOREACH(i) {
506 		STAILQ_INIT(&ktls_wq[i].m_head);
507 		STAILQ_INIT(&ktls_wq[i].so_head);
508 		mtx_init(&ktls_wq[i].mtx, "ktls work queue", NULL, MTX_DEF);
509 		if (ktls_bind_threads > 1) {
510 			pc = pcpu_find(i);
511 			domain = pc->pc_domain;
512 			count = ktls_domains[domain].count;
513 			ktls_domains[domain].cpu[count] = i;
514 			ktls_domains[domain].count++;
515 		}
516 		ktls_cpuid_lookup[ktls_number_threads] = i;
517 		ktls_number_threads++;
518 	}
519 
520 	/*
521 	 * If we somehow have an empty domain, fall back to choosing
522 	 * among all KTLS threads.
523 	 */
524 	if (ktls_bind_threads > 1) {
525 		for (i = 0; i < vm_ndomains; i++) {
526 			if (ktls_domains[i].count == 0) {
527 				ktls_bind_threads = 1;
528 				break;
529 			}
530 		}
531 	}
532 
533 	/* Start kthreads for each workqueue. */
534 	CPU_FOREACH(i) {
535 		error = kproc_kthread_add(ktls_work_thread, &ktls_wq[i],
536 		    &ktls_proc, &td, 0, 0, "KTLS", "thr_%d", i);
537 		if (error) {
538 			printf("Can't add KTLS thread %d error %d\n", i, error);
539 			return (error);
540 		}
541 	}
542 
543 	/*
544 	 * Start an allocation thread per-domain to perform blocking allocations
545 	 * of 16k physically contiguous TLS crypto destination buffers.
546 	 */
547 	if (ktls_sw_buffer_cache) {
548 		for (domain = 0; domain < vm_ndomains; domain++) {
549 			if (VM_DOMAIN_EMPTY(domain))
550 				continue;
551 			if (CPU_EMPTY(&cpuset_domain[domain]))
552 				continue;
553 			error = kproc_kthread_add(ktls_reclaim_thread,
554 			    &ktls_domains[domain], &ktls_proc,
555 			    &ktls_domains[domain].reclaim_td.td,
556 			    0, 0, "KTLS", "reclaim_%d", domain);
557 			if (error) {
558 				printf("Can't add KTLS reclaim thread %d error %d\n",
559 				    domain, error);
560 				return (error);
561 			}
562 		}
563 	}
564 
565 	if (bootverbose)
566 		printf("KTLS: Initialized %d threads\n", ktls_number_threads);
567 	return (0);
568 }
569 
570 static int
ktls_start_kthreads(void)571 ktls_start_kthreads(void)
572 {
573 	int error, state;
574 
575 start:
576 	state = atomic_load_acq_int(&ktls_init_state);
577 	if (__predict_true(state > 0))
578 		return (0);
579 	if (state < 0)
580 		return (ENXIO);
581 
582 	sx_xlock(&ktls_init_lock);
583 	if (ktls_init_state != 0) {
584 		sx_xunlock(&ktls_init_lock);
585 		goto start;
586 	}
587 
588 	error = ktls_init();
589 	if (error == 0)
590 		state = 1;
591 	else
592 		state = -1;
593 	atomic_store_rel_int(&ktls_init_state, state);
594 	sx_xunlock(&ktls_init_lock);
595 	return (error);
596 }
597 
598 static int
ktls_create_session(struct socket * so,struct tls_enable * en,struct ktls_session ** tlsp,int direction)599 ktls_create_session(struct socket *so, struct tls_enable *en,
600     struct ktls_session **tlsp, int direction)
601 {
602 	struct ktls_session *tls;
603 	int error;
604 
605 	/* Only TLS 1.0 - 1.3 are supported. */
606 	if (en->tls_vmajor != TLS_MAJOR_VER_ONE)
607 		return (EINVAL);
608 	if (en->tls_vminor < TLS_MINOR_VER_ZERO ||
609 	    en->tls_vminor > TLS_MINOR_VER_THREE)
610 		return (EINVAL);
611 
612 
613 	/* No flags are currently supported. */
614 	if (en->flags != 0)
615 		return (EINVAL);
616 
617 	/* Common checks for supported algorithms. */
618 	switch (en->cipher_algorithm) {
619 	case CRYPTO_AES_NIST_GCM_16:
620 		/*
621 		 * auth_algorithm isn't used, but permit GMAC values
622 		 * for compatibility.
623 		 */
624 		switch (en->auth_algorithm) {
625 		case 0:
626 #ifdef COMPAT_FREEBSD12
627 		/* XXX: Really 13.0-current COMPAT. */
628 		case CRYPTO_AES_128_NIST_GMAC:
629 		case CRYPTO_AES_192_NIST_GMAC:
630 		case CRYPTO_AES_256_NIST_GMAC:
631 #endif
632 			break;
633 		default:
634 			return (EINVAL);
635 		}
636 		if (en->auth_key_len != 0)
637 			return (EINVAL);
638 		switch (en->tls_vminor) {
639 		case TLS_MINOR_VER_TWO:
640 			if (en->iv_len != TLS_AEAD_GCM_LEN)
641 				return (EINVAL);
642 			break;
643 		case TLS_MINOR_VER_THREE:
644 			if (en->iv_len != TLS_1_3_GCM_IV_LEN)
645 				return (EINVAL);
646 			break;
647 		default:
648 			return (EINVAL);
649 		}
650 		break;
651 	case CRYPTO_AES_CBC:
652 		switch (en->auth_algorithm) {
653 		case CRYPTO_SHA1_HMAC:
654 			break;
655 		case CRYPTO_SHA2_256_HMAC:
656 		case CRYPTO_SHA2_384_HMAC:
657 			if (en->tls_vminor != TLS_MINOR_VER_TWO)
658 				return (EINVAL);
659 			break;
660 		default:
661 			return (EINVAL);
662 		}
663 		if (en->auth_key_len == 0)
664 			return (EINVAL);
665 
666 		/*
667 		 * TLS 1.0 requires an implicit IV.  TLS 1.1 and 1.2
668 		 * use explicit IVs.
669 		 */
670 		switch (en->tls_vminor) {
671 		case TLS_MINOR_VER_ZERO:
672 			if (en->iv_len != TLS_CBC_IMPLICIT_IV_LEN)
673 				return (EINVAL);
674 			break;
675 		case TLS_MINOR_VER_ONE:
676 		case TLS_MINOR_VER_TWO:
677 			/* Ignore any supplied IV. */
678 			en->iv_len = 0;
679 			break;
680 		default:
681 			return (EINVAL);
682 		}
683 		break;
684 	case CRYPTO_CHACHA20_POLY1305:
685 		if (en->auth_algorithm != 0 || en->auth_key_len != 0)
686 			return (EINVAL);
687 		if (en->tls_vminor != TLS_MINOR_VER_TWO &&
688 		    en->tls_vminor != TLS_MINOR_VER_THREE)
689 			return (EINVAL);
690 		if (en->iv_len != TLS_CHACHA20_IV_LEN)
691 			return (EINVAL);
692 		break;
693 	default:
694 		return (EINVAL);
695 	}
696 
697 	error = ktls_start_kthreads();
698 	if (error != 0)
699 		return (error);
700 
701 	tls = uma_zalloc(ktls_session_zone, M_WAITOK | M_ZERO);
702 
703 	counter_u64_add(ktls_offload_active, 1);
704 
705 	refcount_init(&tls->refcount, 1);
706 	if (direction == KTLS_RX) {
707 		TASK_INIT(&tls->reset_tag_task, 0, ktls_reset_receive_tag, tls);
708 	} else {
709 		TASK_INIT(&tls->reset_tag_task, 0, ktls_reset_send_tag, tls);
710 		tls->inp = so->so_pcb;
711 		in_pcbref(tls->inp);
712 		tls->tx = true;
713 	}
714 
715 	tls->wq_index = ktls_get_cpu(so);
716 
717 	tls->params.cipher_algorithm = en->cipher_algorithm;
718 	tls->params.auth_algorithm = en->auth_algorithm;
719 	tls->params.tls_vmajor = en->tls_vmajor;
720 	tls->params.tls_vminor = en->tls_vminor;
721 	tls->params.flags = en->flags;
722 	tls->params.max_frame_len = min(TLS_MAX_MSG_SIZE_V10_2, ktls_maxlen);
723 
724 	/* Set the header and trailer lengths. */
725 	tls->params.tls_hlen = sizeof(struct tls_record_layer);
726 	switch (en->cipher_algorithm) {
727 	case CRYPTO_AES_NIST_GCM_16:
728 		/*
729 		 * TLS 1.2 uses a 4 byte implicit IV with an explicit 8 byte
730 		 * nonce.  TLS 1.3 uses a 12 byte implicit IV.
731 		 */
732 		if (en->tls_vminor < TLS_MINOR_VER_THREE)
733 			tls->params.tls_hlen += sizeof(uint64_t);
734 		tls->params.tls_tlen = AES_GMAC_HASH_LEN;
735 		tls->params.tls_bs = 1;
736 		break;
737 	case CRYPTO_AES_CBC:
738 		switch (en->auth_algorithm) {
739 		case CRYPTO_SHA1_HMAC:
740 			if (en->tls_vminor == TLS_MINOR_VER_ZERO) {
741 				/* Implicit IV, no nonce. */
742 				tls->sequential_records = true;
743 				tls->next_seqno = be64dec(en->rec_seq);
744 				STAILQ_INIT(&tls->pending_records);
745 			} else {
746 				tls->params.tls_hlen += AES_BLOCK_LEN;
747 			}
748 			tls->params.tls_tlen = AES_BLOCK_LEN +
749 			    SHA1_HASH_LEN;
750 			break;
751 		case CRYPTO_SHA2_256_HMAC:
752 			tls->params.tls_hlen += AES_BLOCK_LEN;
753 			tls->params.tls_tlen = AES_BLOCK_LEN +
754 			    SHA2_256_HASH_LEN;
755 			break;
756 		case CRYPTO_SHA2_384_HMAC:
757 			tls->params.tls_hlen += AES_BLOCK_LEN;
758 			tls->params.tls_tlen = AES_BLOCK_LEN +
759 			    SHA2_384_HASH_LEN;
760 			break;
761 		default:
762 			panic("invalid hmac");
763 		}
764 		tls->params.tls_bs = AES_BLOCK_LEN;
765 		break;
766 	case CRYPTO_CHACHA20_POLY1305:
767 		/*
768 		 * Chacha20 uses a 12 byte implicit IV.
769 		 */
770 		tls->params.tls_tlen = POLY1305_HASH_LEN;
771 		tls->params.tls_bs = 1;
772 		break;
773 	default:
774 		panic("invalid cipher");
775 	}
776 
777 	/*
778 	 * TLS 1.3 includes optional padding which we do not support,
779 	 * and also puts the "real" record type at the end of the
780 	 * encrypted data.
781 	 */
782 	if (en->tls_vminor == TLS_MINOR_VER_THREE)
783 		tls->params.tls_tlen += sizeof(uint8_t);
784 
785 	KASSERT(tls->params.tls_hlen <= MBUF_PEXT_HDR_LEN,
786 	    ("TLS header length too long: %d", tls->params.tls_hlen));
787 	KASSERT(tls->params.tls_tlen <= MBUF_PEXT_TRAIL_LEN,
788 	    ("TLS trailer length too long: %d", tls->params.tls_tlen));
789 
790 	if (en->auth_key_len != 0) {
791 		tls->params.auth_key_len = en->auth_key_len;
792 		tls->params.auth_key = malloc(en->auth_key_len, M_KTLS,
793 		    M_WAITOK);
794 		bcopy(en->auth_key, tls->params.auth_key, en->auth_key_len);
795 	}
796 
797 	tls->params.cipher_key_len = en->cipher_key_len;
798 	tls->params.cipher_key = malloc(en->cipher_key_len, M_KTLS, M_WAITOK);
799 	bcopy(en->cipher_key, tls->params.cipher_key, en->cipher_key_len);
800 
801 	/*
802 	 * This holds the implicit portion of the nonce for AEAD
803 	 * ciphers and the initial implicit IV for TLS 1.0.  The
804 	 * explicit portions of the IV are generated in ktls_frame().
805 	 */
806 	if (en->iv_len != 0) {
807 		tls->params.iv_len = en->iv_len;
808 		bcopy(en->iv, tls->params.iv, en->iv_len);
809 
810 		/*
811 		 * For TLS 1.2 with GCM, generate an 8-byte nonce as a
812 		 * counter to generate unique explicit IVs.
813 		 *
814 		 * Store this counter in the last 8 bytes of the IV
815 		 * array so that it is 8-byte aligned.
816 		 */
817 		if (en->cipher_algorithm == CRYPTO_AES_NIST_GCM_16 &&
818 		    en->tls_vminor == TLS_MINOR_VER_TWO)
819 			arc4rand(tls->params.iv + 8, sizeof(uint64_t), 0);
820 	}
821 
822 	tls->gen = 0;
823 	*tlsp = tls;
824 	return (0);
825 }
826 
827 static struct ktls_session *
ktls_clone_session(struct ktls_session * tls,int direction)828 ktls_clone_session(struct ktls_session *tls, int direction)
829 {
830 	struct ktls_session *tls_new;
831 
832 	tls_new = uma_zalloc(ktls_session_zone, M_WAITOK | M_ZERO);
833 
834 	counter_u64_add(ktls_offload_active, 1);
835 
836 	refcount_init(&tls_new->refcount, 1);
837 	if (direction == KTLS_RX) {
838 		TASK_INIT(&tls_new->reset_tag_task, 0, ktls_reset_receive_tag,
839 		    tls_new);
840 	} else {
841 		TASK_INIT(&tls_new->reset_tag_task, 0, ktls_reset_send_tag,
842 		    tls_new);
843 		tls_new->inp = tls->inp;
844 		tls_new->tx = true;
845 		in_pcbref(tls_new->inp);
846 	}
847 
848 	/* Copy fields from existing session. */
849 	tls_new->params = tls->params;
850 	tls_new->wq_index = tls->wq_index;
851 
852 	/* Deep copy keys. */
853 	if (tls_new->params.auth_key != NULL) {
854 		tls_new->params.auth_key = malloc(tls->params.auth_key_len,
855 		    M_KTLS, M_WAITOK);
856 		memcpy(tls_new->params.auth_key, tls->params.auth_key,
857 		    tls->params.auth_key_len);
858 	}
859 
860 	tls_new->params.cipher_key = malloc(tls->params.cipher_key_len, M_KTLS,
861 	    M_WAITOK);
862 	memcpy(tls_new->params.cipher_key, tls->params.cipher_key,
863 	    tls->params.cipher_key_len);
864 
865 	tls_new->gen = 0;
866 	return (tls_new);
867 }
868 
869 #ifdef TCP_OFFLOAD
870 static int
ktls_try_toe(struct socket * so,struct ktls_session * tls,int direction)871 ktls_try_toe(struct socket *so, struct ktls_session *tls, int direction)
872 {
873 	struct inpcb *inp = sotoinpcb(so);
874 	struct tcpcb *tp = intotcpcb(inp);
875 	int error;
876 
877 	INP_WLOCK(inp);
878 	if (tp->t_flags & TF_DISCONNECTED) {
879 		INP_WUNLOCK(inp);
880 		return (ECONNRESET);
881 	}
882 	if (!(tp->t_flags & TF_TOE)) {
883 		INP_WUNLOCK(inp);
884 		return (EOPNOTSUPP);
885 	}
886 
887 	error = tcp_offload_alloc_tls_session(tp, tls, direction);
888 	INP_WUNLOCK(inp);
889 	if (error == 0) {
890 		tls->mode = TCP_TLS_MODE_TOE;
891 		switch (tls->params.cipher_algorithm) {
892 		case CRYPTO_AES_CBC:
893 			counter_u64_add(ktls_toe_cbc, 1);
894 			break;
895 		case CRYPTO_AES_NIST_GCM_16:
896 			counter_u64_add(ktls_toe_gcm, 1);
897 			break;
898 		case CRYPTO_CHACHA20_POLY1305:
899 			counter_u64_add(ktls_toe_chacha20, 1);
900 			break;
901 		}
902 	}
903 	return (error);
904 }
905 #endif
906 
907 /*
908  * Common code used when first enabling ifnet TLS on a connection or
909  * when allocating a new ifnet TLS session due to a routing change.
910  * This function allocates a new TLS send tag on whatever interface
911  * the connection is currently routed over.
912  */
913 static int
ktls_alloc_snd_tag(struct inpcb * inp,struct ktls_session * tls,bool force,struct m_snd_tag ** mstp)914 ktls_alloc_snd_tag(struct inpcb *inp, struct ktls_session *tls, bool force,
915     struct m_snd_tag **mstp)
916 {
917 	union if_snd_tag_alloc_params params;
918 	struct ifnet *ifp;
919 	struct nhop_object *nh;
920 	struct tcpcb *tp = intotcpcb(inp);
921 	int error;
922 
923 	INP_RLOCK(inp);
924 	if (tp->t_flags & TF_DISCONNECTED) {
925 		INP_RUNLOCK(inp);
926 		return (ECONNRESET);
927 	}
928 
929 	/*
930 	 * Check administrative controls on ifnet TLS to determine if
931 	 * ifnet TLS should be denied.
932 	 *
933 	 * - Always permit 'force' requests.
934 	 * - ktls_ifnet_permitted == 0: always deny.
935 	 */
936 	if (!force && ktls_ifnet_permitted == 0) {
937 		INP_RUNLOCK(inp);
938 		return (ENXIO);
939 	}
940 
941 	/*
942 	 * XXX: Use the cached route in the inpcb to find the
943 	 * interface.  This should perhaps instead use
944 	 * rtalloc1_fib(dst, 0, 0, fibnum).  Since KTLS is only
945 	 * enabled after a connection has completed key negotiation in
946 	 * userland, the cached route will be present in practice.
947 	 */
948 	nh = inp->inp_route.ro_nh;
949 	if (nh == NULL) {
950 		INP_RUNLOCK(inp);
951 		return (ENXIO);
952 	}
953 	ifp = nh->nh_ifp;
954 	if_ref(ifp);
955 
956 	/*
957 	 * Allocate a TLS + ratelimit tag if the connection has an
958 	 * existing pacing rate.
959 	 */
960 	if (tp->t_pacing_rate != -1 &&
961 	    (if_getcapenable(ifp) & IFCAP_TXTLS_RTLMT) != 0) {
962 		params.hdr.type = IF_SND_TAG_TYPE_TLS_RATE_LIMIT;
963 		params.tls_rate_limit.inp = inp;
964 		params.tls_rate_limit.tls = tls;
965 		params.tls_rate_limit.max_rate = tp->t_pacing_rate;
966 	} else {
967 		params.hdr.type = IF_SND_TAG_TYPE_TLS;
968 		params.tls.inp = inp;
969 		params.tls.tls = tls;
970 	}
971 	params.hdr.flowid = inp->inp_flowid;
972 	params.hdr.flowtype = inp->inp_flowtype;
973 	params.hdr.numa_domain = inp->inp_numa_domain;
974 	INP_RUNLOCK(inp);
975 
976 	if ((if_getcapenable(ifp) & IFCAP_MEXTPG) == 0) {
977 		error = EOPNOTSUPP;
978 		goto out;
979 	}
980 	if (inp->inp_vflag & INP_IPV6) {
981 		if ((if_getcapenable(ifp) & IFCAP_TXTLS6) == 0) {
982 			error = EOPNOTSUPP;
983 			goto out;
984 		}
985 	} else {
986 		if ((if_getcapenable(ifp) & IFCAP_TXTLS4) == 0) {
987 			error = EOPNOTSUPP;
988 			goto out;
989 		}
990 	}
991 	error = m_snd_tag_alloc(ifp, &params, mstp);
992 out:
993 	if_rele(ifp);
994 	return (error);
995 }
996 
997 /*
998  * Allocate an initial TLS receive tag for doing HW decryption of TLS
999  * data.
1000  *
1001  * This function allocates a new TLS receive tag on whatever interface
1002  * the connection is currently routed over.  If the connection ends up
1003  * using a different interface for receive this will get fixed up via
1004  * ktls_input_ifp_mismatch as future packets arrive.
1005  */
1006 static int
ktls_alloc_rcv_tag(struct inpcb * inp,struct ktls_session * tls,struct m_snd_tag ** mstp)1007 ktls_alloc_rcv_tag(struct inpcb *inp, struct ktls_session *tls,
1008     struct m_snd_tag **mstp)
1009 {
1010 	union if_snd_tag_alloc_params params;
1011 	struct ifnet *ifp;
1012 	struct nhop_object *nh;
1013 	int error;
1014 
1015 	if (!ktls_ocf_recrypt_supported(tls))
1016 		return (ENXIO);
1017 
1018 	INP_RLOCK(inp);
1019 	if (intotcpcb(inp)->t_flags & TF_DISCONNECTED) {
1020 		INP_RUNLOCK(inp);
1021 		return (ECONNRESET);
1022 	}
1023 
1024 	/*
1025 	 * Check administrative controls on ifnet TLS to determine if
1026 	 * ifnet TLS should be denied.
1027 	 */
1028 	if (ktls_ifnet_permitted == 0) {
1029 		INP_RUNLOCK(inp);
1030 		return (ENXIO);
1031 	}
1032 
1033 	/*
1034 	 * XXX: As with ktls_alloc_snd_tag, use the cached route in
1035 	 * the inpcb to find the interface.
1036 	 */
1037 	nh = inp->inp_route.ro_nh;
1038 	if (nh == NULL) {
1039 		INP_RUNLOCK(inp);
1040 		return (ENXIO);
1041 	}
1042 	ifp = nh->nh_ifp;
1043 	if_ref(ifp);
1044 	tls->rx_ifp = ifp;
1045 
1046 	params.hdr.type = IF_SND_TAG_TYPE_TLS_RX;
1047 	params.hdr.flowid = inp->inp_flowid;
1048 	params.hdr.flowtype = inp->inp_flowtype;
1049 	params.hdr.numa_domain = inp->inp_numa_domain;
1050 	params.tls_rx.inp = inp;
1051 	params.tls_rx.tls = tls;
1052 	params.tls_rx.vlan_id = 0;
1053 
1054 	INP_RUNLOCK(inp);
1055 
1056 	if (inp->inp_vflag & INP_IPV6) {
1057 		if ((if_getcapenable2(ifp) & IFCAP2_BIT(IFCAP2_RXTLS6)) == 0) {
1058 			error = EOPNOTSUPP;
1059 			goto out;
1060 		}
1061 	} else {
1062 		if ((if_getcapenable2(ifp) & IFCAP2_BIT(IFCAP2_RXTLS4)) == 0) {
1063 			error = EOPNOTSUPP;
1064 			goto out;
1065 		}
1066 	}
1067 	error = m_snd_tag_alloc(ifp, &params, mstp);
1068 
1069 	/*
1070 	 * If this connection is over a vlan, vlan_snd_tag_alloc
1071 	 * rewrites vlan_id with the saved interface.  Save the VLAN
1072 	 * ID for use in ktls_reset_receive_tag which allocates new
1073 	 * receive tags directly from the leaf interface bypassing
1074 	 * if_vlan.
1075 	 */
1076 	if (error == 0)
1077 		tls->rx_vlan_id = params.tls_rx.vlan_id;
1078 out:
1079 	return (error);
1080 }
1081 
1082 static int
ktls_try_ifnet(struct socket * so,struct ktls_session * tls,int direction,bool force)1083 ktls_try_ifnet(struct socket *so, struct ktls_session *tls, int direction,
1084     bool force)
1085 {
1086 	struct m_snd_tag *mst;
1087 	int error;
1088 
1089 	switch (direction) {
1090 	case KTLS_TX:
1091 		error = ktls_alloc_snd_tag(so->so_pcb, tls, force, &mst);
1092 		if (__predict_false(error != 0))
1093 			goto done;
1094 		break;
1095 	case KTLS_RX:
1096 		KASSERT(!force, ("%s: forced receive tag", __func__));
1097 		error = ktls_alloc_rcv_tag(so->so_pcb, tls, &mst);
1098 		if (__predict_false(error != 0))
1099 			goto done;
1100 		break;
1101 	default:
1102 		__assert_unreachable();
1103 	}
1104 
1105 	tls->mode = TCP_TLS_MODE_IFNET;
1106 	tls->snd_tag = mst;
1107 
1108 	switch (tls->params.cipher_algorithm) {
1109 	case CRYPTO_AES_CBC:
1110 		counter_u64_add(ktls_ifnet_cbc, 1);
1111 		break;
1112 	case CRYPTO_AES_NIST_GCM_16:
1113 		counter_u64_add(ktls_ifnet_gcm, 1);
1114 		break;
1115 	case CRYPTO_CHACHA20_POLY1305:
1116 		counter_u64_add(ktls_ifnet_chacha20, 1);
1117 		break;
1118 	default:
1119 		break;
1120 	}
1121 done:
1122 	return (error);
1123 }
1124 
1125 static void
ktls_use_sw(struct ktls_session * tls)1126 ktls_use_sw(struct ktls_session *tls)
1127 {
1128 	tls->mode = TCP_TLS_MODE_SW;
1129 	switch (tls->params.cipher_algorithm) {
1130 	case CRYPTO_AES_CBC:
1131 		counter_u64_add(ktls_sw_cbc, 1);
1132 		break;
1133 	case CRYPTO_AES_NIST_GCM_16:
1134 		counter_u64_add(ktls_sw_gcm, 1);
1135 		break;
1136 	case CRYPTO_CHACHA20_POLY1305:
1137 		counter_u64_add(ktls_sw_chacha20, 1);
1138 		break;
1139 	}
1140 }
1141 
1142 static int
ktls_try_sw(struct ktls_session * tls,int direction)1143 ktls_try_sw(struct ktls_session *tls, int direction)
1144 {
1145 	int error;
1146 
1147 	error = ktls_ocf_try(tls, direction);
1148 	if (error)
1149 		return (error);
1150 	ktls_use_sw(tls);
1151 	return (0);
1152 }
1153 
1154 /*
1155  * KTLS RX stores data in the socket buffer as a list of TLS records,
1156  * where each record is stored as a control message containg the TLS
1157  * header followed by data mbufs containing the decrypted data.  This
1158  * is different from KTLS TX which always uses an mb_ext_pgs mbuf for
1159  * both encrypted and decrypted data.  TLS records decrypted by a NIC
1160  * should be queued to the socket buffer as records, but encrypted
1161  * data which needs to be decrypted by software arrives as a stream of
1162  * regular mbufs which need to be converted.  In addition, there may
1163  * already be pending encrypted data in the socket buffer when KTLS RX
1164  * is enabled.
1165  *
1166  * To manage not-yet-decrypted data for KTLS RX, the following scheme
1167  * is used:
1168  *
1169  * - A single chain of NOTREADY mbufs is hung off of sb_mtls.
1170  *
1171  * - ktls_check_rx checks this chain of mbufs reading the TLS header
1172  *   from the first mbuf.  Once all of the data for that TLS record is
1173  *   queued, the socket is queued to a worker thread.
1174  *
1175  * - The worker thread calls ktls_decrypt to decrypt TLS records in
1176  *   the TLS chain.  Each TLS record is detached from the TLS chain,
1177  *   decrypted, and inserted into the regular socket buffer chain as
1178  *   record starting with a control message holding the TLS header and
1179  *   a chain of mbufs holding the encrypted data.
1180  */
1181 
1182 static void
sb_mark_notready(struct sockbuf * sb)1183 sb_mark_notready(struct sockbuf *sb)
1184 {
1185 	struct mbuf *m;
1186 
1187 	m = sb->sb_mb;
1188 	sb->sb_mtls = m;
1189 	sb->sb_mb = NULL;
1190 	sb->sb_mbtail = NULL;
1191 	sb->sb_lastrecord = NULL;
1192 	for (; m != NULL; m = m->m_next) {
1193 		KASSERT(m->m_nextpkt == NULL, ("%s: m_nextpkt != NULL",
1194 		    __func__));
1195 		KASSERT((m->m_flags & M_NOTREADY) == 0, ("%s: mbuf not ready",
1196 		    __func__));
1197 		KASSERT(sb->sb_acc >= m->m_len, ("%s: sb_acc < m->m_len",
1198 		    __func__));
1199 		m->m_flags |= M_NOTREADY;
1200 		sb->sb_acc -= m->m_len;
1201 		sb->sb_tlscc += m->m_len;
1202 		sb->sb_mtlstail = m;
1203 	}
1204 	KASSERT(sb->sb_acc == 0 && sb->sb_tlscc == sb->sb_ccc,
1205 	    ("%s: acc %u tlscc %u ccc %u", __func__, sb->sb_acc, sb->sb_tlscc,
1206 	    sb->sb_ccc));
1207 }
1208 
1209 /*
1210  * Return information about the pending TLS data in a socket
1211  * buffer.  On return, 'seqno' is set to the sequence number
1212  * of the next TLS record to be received, 'resid' is set to
1213  * the amount of bytes still needed for the last pending
1214  * record.  The function returns 'false' if the last pending
1215  * record contains a partial TLS header.  In that case, 'resid'
1216  * is the number of bytes needed to complete the TLS header.
1217  */
1218 bool
ktls_pending_rx_info(struct sockbuf * sb,uint64_t * seqnop,size_t * residp)1219 ktls_pending_rx_info(struct sockbuf *sb, uint64_t *seqnop, size_t *residp)
1220 {
1221 	struct tls_record_layer hdr;
1222 	struct mbuf *m;
1223 	uint64_t seqno;
1224 	size_t resid;
1225 	u_int offset, record_len;
1226 
1227 	SOCKBUF_LOCK_ASSERT(sb);
1228 	MPASS(sb->sb_flags & SB_TLS_RX);
1229 	seqno = sb->sb_tls_seqno;
1230 	resid = sb->sb_tlscc;
1231 	m = sb->sb_mtls;
1232 	offset = 0;
1233 
1234 	if (resid == 0) {
1235 		*seqnop = seqno;
1236 		*residp = 0;
1237 		return (true);
1238 	}
1239 
1240 	for (;;) {
1241 		seqno++;
1242 
1243 		if (resid < sizeof(hdr)) {
1244 			*seqnop = seqno;
1245 			*residp = sizeof(hdr) - resid;
1246 			return (false);
1247 		}
1248 
1249 		m_copydata(m, offset, sizeof(hdr), (void *)&hdr);
1250 
1251 		record_len = sizeof(hdr) + ntohs(hdr.tls_length);
1252 		if (resid <= record_len) {
1253 			*seqnop = seqno;
1254 			*residp = record_len - resid;
1255 			return (true);
1256 		}
1257 		resid -= record_len;
1258 
1259 		while (record_len != 0) {
1260 			if (m->m_len - offset > record_len) {
1261 				offset += record_len;
1262 				break;
1263 			}
1264 
1265 			record_len -= (m->m_len - offset);
1266 			offset = 0;
1267 			m = m->m_next;
1268 		}
1269 	}
1270 }
1271 
1272 int
ktls_enable_rx(struct socket * so,struct tls_enable * en)1273 ktls_enable_rx(struct socket *so, struct tls_enable *en)
1274 {
1275 	struct ktls_session *tls;
1276 	int error;
1277 
1278 	if (!ktls_offload_enable)
1279 		return (ENOTSUP);
1280 
1281 	counter_u64_add(ktls_offload_enable_calls, 1);
1282 
1283 	/*
1284 	 * This should always be true since only the TCP socket option
1285 	 * invokes this function.
1286 	 */
1287 	if (so->so_proto->pr_protocol != IPPROTO_TCP)
1288 		return (EINVAL);
1289 
1290 	/*
1291 	 * XXX: Don't overwrite existing sessions.  We should permit
1292 	 * this to support rekeying in the future.
1293 	 */
1294 	if (so->so_rcv.sb_tls_info != NULL)
1295 		return (EALREADY);
1296 
1297 	if (en->cipher_algorithm == CRYPTO_AES_CBC && !ktls_cbc_enable)
1298 		return (ENOTSUP);
1299 
1300 	error = ktls_create_session(so, en, &tls, KTLS_RX);
1301 	if (error)
1302 		return (error);
1303 
1304 	error = ktls_ocf_try(tls, KTLS_RX);
1305 	if (error) {
1306 		ktls_free(tls);
1307 		return (error);
1308 	}
1309 
1310 	/*
1311 	 * Serialize with soreceive_generic() and make sure that we're not
1312 	 * operating on a listening socket.
1313 	 */
1314 	error = SOCK_IO_RECV_LOCK(so, SBL_WAIT);
1315 	if (error) {
1316 		ktls_free(tls);
1317 		return (error);
1318 	}
1319 
1320 	/* Mark the socket as using TLS offload. */
1321 	SOCK_RECVBUF_LOCK(so);
1322 	if (__predict_false(so->so_rcv.sb_tls_info != NULL))
1323 		error = EALREADY;
1324 	else if ((so->so_rcv.sb_flags & SB_SPLICED) != 0)
1325 		error = EINVAL;
1326 	if (error != 0) {
1327 		SOCK_RECVBUF_UNLOCK(so);
1328 		SOCK_IO_RECV_UNLOCK(so);
1329 		ktls_free(tls);
1330 		return (EALREADY);
1331 	}
1332 	so->so_rcv.sb_tls_seqno = be64dec(en->rec_seq);
1333 	so->so_rcv.sb_tls_info = tls;
1334 	so->so_rcv.sb_flags |= SB_TLS_RX;
1335 
1336 	/* Mark existing data as not ready until it can be decrypted. */
1337 	sb_mark_notready(&so->so_rcv);
1338 	ktls_check_rx(&so->so_rcv);
1339 	SOCK_RECVBUF_UNLOCK(so);
1340 	SOCK_IO_RECV_UNLOCK(so);
1341 
1342 	/* Prefer TOE -> ifnet TLS -> software TLS. */
1343 #ifdef TCP_OFFLOAD
1344 	error = ktls_try_toe(so, tls, KTLS_RX);
1345 	if (error)
1346 #endif
1347 		error = ktls_try_ifnet(so, tls, KTLS_RX, false);
1348 	if (error)
1349 		ktls_use_sw(tls);
1350 
1351 	counter_u64_add(ktls_offload_total, 1);
1352 
1353 	return (0);
1354 }
1355 
1356 int
ktls_enable_tx(struct socket * so,struct tls_enable * en)1357 ktls_enable_tx(struct socket *so, struct tls_enable *en)
1358 {
1359 	struct ktls_session *tls;
1360 	struct inpcb *inp;
1361 	struct tcpcb *tp;
1362 	int error;
1363 
1364 	if (!ktls_offload_enable)
1365 		return (ENOTSUP);
1366 
1367 	counter_u64_add(ktls_offload_enable_calls, 1);
1368 
1369 	/*
1370 	 * This should always be true since only the TCP socket option
1371 	 * invokes this function.
1372 	 */
1373 	if (so->so_proto->pr_protocol != IPPROTO_TCP)
1374 		return (EINVAL);
1375 
1376 	/*
1377 	 * XXX: Don't overwrite existing sessions.  We should permit
1378 	 * this to support rekeying in the future.
1379 	 */
1380 	if (so->so_snd.sb_tls_info != NULL)
1381 		return (EALREADY);
1382 
1383 	if (en->cipher_algorithm == CRYPTO_AES_CBC && !ktls_cbc_enable)
1384 		return (ENOTSUP);
1385 
1386 	/* TLS requires ext pgs */
1387 	if (mb_use_ext_pgs == 0)
1388 		return (ENXIO);
1389 
1390 	error = ktls_create_session(so, en, &tls, KTLS_TX);
1391 	if (error)
1392 		return (error);
1393 
1394 	/* some ktls offload NICs require initial seqno to start offload */
1395 	tls->initial_offload_seqno = be64dec(en->rec_seq);
1396 
1397 	/* Prefer TOE -> ifnet TLS -> software TLS. */
1398 #ifdef TCP_OFFLOAD
1399 	error = ktls_try_toe(so, tls, KTLS_TX);
1400 	if (error)
1401 #endif
1402 		error = ktls_try_ifnet(so, tls, KTLS_TX, false);
1403 	if (error)
1404 		error = ktls_try_sw(tls, KTLS_TX);
1405 
1406 	if (error) {
1407 		ktls_free(tls);
1408 		return (error);
1409 	}
1410 
1411 	/*
1412 	 * Serialize with sosend_generic() and make sure that we're not
1413 	 * operating on a listening socket.
1414 	 */
1415 	error = SOCK_IO_SEND_LOCK(so, SBL_WAIT);
1416 	if (error) {
1417 		ktls_free(tls);
1418 		return (error);
1419 	}
1420 
1421 	/*
1422 	 * Write lock the INP when setting sb_tls_info so that
1423 	 * routines in tcp_ratelimit.c can read sb_tls_info while
1424 	 * holding the INP lock.
1425 	 */
1426 	inp = so->so_pcb;
1427 	INP_WLOCK(inp);
1428 	SOCK_SENDBUF_LOCK(so);
1429 	if (__predict_false(so->so_snd.sb_tls_info != NULL))
1430 		error = EALREADY;
1431 	else if ((so->so_snd.sb_flags & SB_SPLICED) != 0)
1432 		error = EINVAL;
1433 	if (error != 0) {
1434 		SOCK_SENDBUF_UNLOCK(so);
1435 		INP_WUNLOCK(inp);
1436 		SOCK_IO_SEND_UNLOCK(so);
1437 		ktls_free(tls);
1438 		return (error);
1439 	}
1440 	so->so_snd.sb_tls_seqno = be64dec(en->rec_seq);
1441 	so->so_snd.sb_tls_info = tls;
1442 	if (tls->mode != TCP_TLS_MODE_SW) {
1443 		tp = intotcpcb(inp);
1444 		MPASS(tp->t_nic_ktls_xmit == 0);
1445 		tp->t_nic_ktls_xmit = 1;
1446 		if (tp->t_fb->tfb_hwtls_change != NULL)
1447 			(*tp->t_fb->tfb_hwtls_change)(tp, 1);
1448 	}
1449 	SOCK_SENDBUF_UNLOCK(so);
1450 	INP_WUNLOCK(inp);
1451 	SOCK_IO_SEND_UNLOCK(so);
1452 
1453 	counter_u64_add(ktls_offload_total, 1);
1454 
1455 	return (0);
1456 }
1457 
1458 int
ktls_get_rx_mode(struct socket * so,int * modep)1459 ktls_get_rx_mode(struct socket *so, int *modep)
1460 {
1461 	struct ktls_session *tls;
1462 	struct inpcb *inp __diagused;
1463 
1464 	if (SOLISTENING(so))
1465 		return (EINVAL);
1466 	inp = so->so_pcb;
1467 	INP_WLOCK_ASSERT(inp);
1468 	SOCK_RECVBUF_LOCK(so);
1469 	tls = so->so_rcv.sb_tls_info;
1470 	if (tls == NULL)
1471 		*modep = TCP_TLS_MODE_NONE;
1472 	else
1473 		*modep = tls->mode;
1474 	SOCK_RECVBUF_UNLOCK(so);
1475 	return (0);
1476 }
1477 
1478 /*
1479  * ktls_get_rx_sequence - get the next TCP- and TLS- sequence number.
1480  *
1481  * This function gets information about the next TCP- and TLS-
1482  * sequence number to be processed by the TLS receive worker
1483  * thread. The information is extracted from the given "inpcb"
1484  * structure. The values are stored in host endian format at the two
1485  * given output pointer locations. The TCP sequence number points to
1486  * the beginning of the TLS header.
1487  *
1488  * This function returns zero on success, else a non-zero error code
1489  * is returned.
1490  */
1491 int
ktls_get_rx_sequence(struct inpcb * inp,uint32_t * tcpseq,uint64_t * tlsseq)1492 ktls_get_rx_sequence(struct inpcb *inp, uint32_t *tcpseq, uint64_t *tlsseq)
1493 {
1494 	struct socket *so = inp->inp_socket;
1495 	struct tcpcb *tp = intotcpcb(inp);
1496 
1497 	INP_RLOCK(inp);
1498 	if (tp->t_flags & TF_DISCONNECTED) {
1499 		INP_RUNLOCK(inp);
1500 		return (ECONNRESET);
1501 	}
1502 
1503 	SOCKBUF_LOCK(&so->so_rcv);
1504 	*tcpseq = tp->rcv_nxt - so->so_rcv.sb_tlscc;
1505 	*tlsseq = so->so_rcv.sb_tls_seqno;
1506 	SOCKBUF_UNLOCK(&so->so_rcv);
1507 
1508 	INP_RUNLOCK(inp);
1509 
1510 	return (0);
1511 }
1512 
1513 int
ktls_get_tx_mode(struct socket * so,int * modep)1514 ktls_get_tx_mode(struct socket *so, int *modep)
1515 {
1516 	struct ktls_session *tls;
1517 	struct inpcb *inp __diagused;
1518 
1519 	if (SOLISTENING(so))
1520 		return (EINVAL);
1521 	inp = so->so_pcb;
1522 	INP_WLOCK_ASSERT(inp);
1523 	SOCK_SENDBUF_LOCK(so);
1524 	tls = so->so_snd.sb_tls_info;
1525 	if (tls == NULL)
1526 		*modep = TCP_TLS_MODE_NONE;
1527 	else
1528 		*modep = tls->mode;
1529 	SOCK_SENDBUF_UNLOCK(so);
1530 	return (0);
1531 }
1532 
1533 /*
1534  * Switch between SW and ifnet TLS sessions as requested.
1535  */
1536 int
ktls_set_tx_mode(struct socket * so,int mode)1537 ktls_set_tx_mode(struct socket *so, int mode)
1538 {
1539 	struct ktls_session *tls, *tls_new;
1540 	struct inpcb *inp;
1541 	struct tcpcb *tp;
1542 	int error;
1543 
1544 	if (SOLISTENING(so))
1545 		return (EINVAL);
1546 	switch (mode) {
1547 	case TCP_TLS_MODE_SW:
1548 	case TCP_TLS_MODE_IFNET:
1549 		break;
1550 	default:
1551 		return (EINVAL);
1552 	}
1553 
1554 	inp = so->so_pcb;
1555 	INP_WLOCK_ASSERT(inp);
1556 	tp = intotcpcb(inp);
1557 
1558 	if (mode == TCP_TLS_MODE_IFNET) {
1559 		/* Don't allow enabling ifnet ktls multiple times */
1560 		if (tp->t_nic_ktls_xmit)
1561 			return (EALREADY);
1562 
1563 		/*
1564 		 * Don't enable ifnet ktls if we disabled it due to an
1565 		 * excessive retransmission rate
1566 		 */
1567 		if (tp->t_nic_ktls_xmit_dis)
1568 			return (ENXIO);
1569 	}
1570 
1571 	SOCKBUF_LOCK(&so->so_snd);
1572 	tls = so->so_snd.sb_tls_info;
1573 	if (tls == NULL) {
1574 		SOCKBUF_UNLOCK(&so->so_snd);
1575 		return (0);
1576 	}
1577 
1578 	if (tls->mode == mode) {
1579 		SOCKBUF_UNLOCK(&so->so_snd);
1580 		return (0);
1581 	}
1582 
1583 	tls = ktls_hold(tls);
1584 	SOCKBUF_UNLOCK(&so->so_snd);
1585 	INP_WUNLOCK(inp);
1586 
1587 	tls_new = ktls_clone_session(tls, KTLS_TX);
1588 
1589 	if (mode == TCP_TLS_MODE_IFNET)
1590 		error = ktls_try_ifnet(so, tls_new, KTLS_TX, true);
1591 	else
1592 		error = ktls_try_sw(tls_new, KTLS_TX);
1593 	if (error) {
1594 		counter_u64_add(ktls_switch_failed, 1);
1595 		ktls_free(tls_new);
1596 		ktls_free(tls);
1597 		INP_WLOCK(inp);
1598 		return (error);
1599 	}
1600 
1601 	error = SOCK_IO_SEND_LOCK(so, SBL_WAIT);
1602 	if (error) {
1603 		counter_u64_add(ktls_switch_failed, 1);
1604 		ktls_free(tls_new);
1605 		ktls_free(tls);
1606 		INP_WLOCK(inp);
1607 		return (error);
1608 	}
1609 
1610 	/*
1611 	 * If we raced with another session change, keep the existing
1612 	 * session.
1613 	 */
1614 	if (tls != so->so_snd.sb_tls_info) {
1615 		counter_u64_add(ktls_switch_failed, 1);
1616 		SOCK_IO_SEND_UNLOCK(so);
1617 		ktls_free(tls_new);
1618 		ktls_free(tls);
1619 		INP_WLOCK(inp);
1620 		return (EBUSY);
1621 	}
1622 
1623 	INP_WLOCK(inp);
1624 	SOCKBUF_LOCK(&so->so_snd);
1625 	so->so_snd.sb_tls_info = tls_new;
1626 	if (tls_new->mode != TCP_TLS_MODE_SW) {
1627 		MPASS(tp->t_nic_ktls_xmit == 0);
1628 		tp->t_nic_ktls_xmit = 1;
1629 		if (tp->t_fb->tfb_hwtls_change != NULL)
1630 			(*tp->t_fb->tfb_hwtls_change)(tp, 1);
1631 	}
1632 	SOCKBUF_UNLOCK(&so->so_snd);
1633 	SOCK_IO_SEND_UNLOCK(so);
1634 
1635 	/*
1636 	 * Drop two references on 'tls'.  The first is for the
1637 	 * ktls_hold() above.  The second drops the reference from the
1638 	 * socket buffer.
1639 	 */
1640 	KASSERT(tls->refcount >= 2, ("too few references on old session"));
1641 	ktls_free(tls);
1642 	ktls_free(tls);
1643 
1644 	if (mode == TCP_TLS_MODE_IFNET)
1645 		counter_u64_add(ktls_switch_to_ifnet, 1);
1646 	else
1647 		counter_u64_add(ktls_switch_to_sw, 1);
1648 
1649 	return (0);
1650 }
1651 
1652 /*
1653  * Try to allocate a new TLS receive tag.  This task is scheduled when
1654  * sbappend_ktls_rx detects an input path change.  If a new tag is
1655  * allocated, replace the tag in the TLS session.  If a new tag cannot
1656  * be allocated, let the session fall back to software decryption.
1657  */
1658 static void
ktls_reset_receive_tag(void * context,int pending)1659 ktls_reset_receive_tag(void *context, int pending)
1660 {
1661 	union if_snd_tag_alloc_params params;
1662 	struct ktls_session *tls;
1663 	struct m_snd_tag *mst;
1664 	struct inpcb *inp;
1665 	struct ifnet *ifp;
1666 	struct socket *so;
1667 	int error;
1668 
1669 	MPASS(pending == 1);
1670 
1671 	tls = context;
1672 	so = tls->so;
1673 	inp = so->so_pcb;
1674 	ifp = NULL;
1675 
1676 	INP_RLOCK(inp);
1677 	if (intotcpcb(inp)->t_flags & TF_DISCONNECTED) {
1678 		INP_RUNLOCK(inp);
1679 		goto out;
1680 	}
1681 
1682 	SOCKBUF_LOCK(&so->so_rcv);
1683 	mst = tls->snd_tag;
1684 	tls->snd_tag = NULL;
1685 	if (mst != NULL)
1686 		m_snd_tag_rele(mst);
1687 
1688 	ifp = tls->rx_ifp;
1689 	if_ref(ifp);
1690 	SOCKBUF_UNLOCK(&so->so_rcv);
1691 
1692 	params.hdr.type = IF_SND_TAG_TYPE_TLS_RX;
1693 	params.hdr.flowid = inp->inp_flowid;
1694 	params.hdr.flowtype = inp->inp_flowtype;
1695 	params.hdr.numa_domain = inp->inp_numa_domain;
1696 	params.tls_rx.inp = inp;
1697 	params.tls_rx.tls = tls;
1698 	params.tls_rx.vlan_id = tls->rx_vlan_id;
1699 	INP_RUNLOCK(inp);
1700 
1701 	if (inp->inp_vflag & INP_IPV6) {
1702 		if ((if_getcapenable2(ifp) & IFCAP2_RXTLS6) == 0)
1703 			goto out;
1704 	} else {
1705 		if ((if_getcapenable2(ifp) & IFCAP2_RXTLS4) == 0)
1706 			goto out;
1707 	}
1708 
1709 	error = m_snd_tag_alloc(ifp, &params, &mst);
1710 	if (error == 0) {
1711 		SOCKBUF_LOCK(&so->so_rcv);
1712 		tls->snd_tag = mst;
1713 		SOCKBUF_UNLOCK(&so->so_rcv);
1714 
1715 		counter_u64_add(ktls_ifnet_reset, 1);
1716 	} else {
1717 		/*
1718 		 * Just fall back to software decryption if a tag
1719 		 * cannot be allocated leaving the connection intact.
1720 		 * If a future input path change switches to another
1721 		 * interface this connection will resume ifnet TLS.
1722 		 */
1723 		counter_u64_add(ktls_ifnet_reset_failed, 1);
1724 	}
1725 
1726 out:
1727 	mtx_pool_lock(mtxpool_sleep, tls);
1728 	tls->reset_pending = false;
1729 	mtx_pool_unlock(mtxpool_sleep, tls);
1730 
1731 	if (ifp != NULL)
1732 		if_rele(ifp);
1733 	CURVNET_SET(so->so_vnet);
1734 	sorele(so);
1735 	CURVNET_RESTORE();
1736 	ktls_free(tls);
1737 }
1738 
1739 /*
1740  * Try to allocate a new TLS send tag.  This task is scheduled when
1741  * ip_output detects a route change while trying to transmit a packet
1742  * holding a TLS record.  If a new tag is allocated, replace the tag
1743  * in the TLS session.  Subsequent packets on the connection will use
1744  * the new tag.  If a new tag cannot be allocated, drop the
1745  * connection.
1746  */
1747 static void
ktls_reset_send_tag(void * context,int pending)1748 ktls_reset_send_tag(void *context, int pending)
1749 {
1750 	struct epoch_tracker et;
1751 	struct ktls_session *tls;
1752 	struct m_snd_tag *old, *new;
1753 	struct inpcb *inp;
1754 	struct tcpcb *tp;
1755 	int error;
1756 
1757 	MPASS(pending == 1);
1758 
1759 	tls = context;
1760 	inp = tls->inp;
1761 
1762 	/*
1763 	 * Free the old tag first before allocating a new one.
1764 	 * ip[6]_output_send() will treat a NULL send tag the same as
1765 	 * an ifp mismatch and drop packets until a new tag is
1766 	 * allocated.
1767 	 *
1768 	 * Write-lock the INP when changing tls->snd_tag since
1769 	 * ip[6]_output_send() holds a read-lock when reading the
1770 	 * pointer.
1771 	 */
1772 	INP_WLOCK(inp);
1773 	old = tls->snd_tag;
1774 	tls->snd_tag = NULL;
1775 	INP_WUNLOCK(inp);
1776 	if (old != NULL)
1777 		m_snd_tag_rele(old);
1778 
1779 	error = ktls_alloc_snd_tag(inp, tls, true, &new);
1780 
1781 	if (error == 0) {
1782 		INP_WLOCK(inp);
1783 		tls->snd_tag = new;
1784 		mtx_pool_lock(mtxpool_sleep, tls);
1785 		tls->reset_pending = false;
1786 		mtx_pool_unlock(mtxpool_sleep, tls);
1787 		INP_WUNLOCK(inp);
1788 
1789 		counter_u64_add(ktls_ifnet_reset, 1);
1790 
1791 		/*
1792 		 * XXX: Should we kick tcp_output explicitly now that
1793 		 * the send tag is fixed or just rely on timers?
1794 		 */
1795 	} else {
1796 		NET_EPOCH_ENTER(et);
1797 		INP_WLOCK(inp);
1798 		tp = intotcpcb(inp);
1799 		if (!(tp->t_flags & TF_DISCONNECTED)) {
1800 			CURVNET_SET(inp->inp_socket->so_vnet);
1801 			tp = tcp_drop(tp, ECONNABORTED);
1802 			CURVNET_RESTORE();
1803 			if (tp != NULL) {
1804 				counter_u64_add(ktls_ifnet_reset_dropped, 1);
1805 				INP_WUNLOCK(inp);
1806 			}
1807 		} else
1808 			INP_WUNLOCK(inp);
1809 		NET_EPOCH_EXIT(et);
1810 
1811 		counter_u64_add(ktls_ifnet_reset_failed, 1);
1812 
1813 		/*
1814 		 * Leave reset_pending true to avoid future tasks while
1815 		 * the socket goes away.
1816 		 */
1817 	}
1818 
1819 	ktls_free(tls);
1820 }
1821 
1822 void
ktls_input_ifp_mismatch(struct sockbuf * sb,struct ifnet * ifp)1823 ktls_input_ifp_mismatch(struct sockbuf *sb, struct ifnet *ifp)
1824 {
1825 	struct ktls_session *tls;
1826 	struct socket *so;
1827 
1828 	SOCKBUF_LOCK_ASSERT(sb);
1829 	KASSERT(sb->sb_flags & SB_TLS_RX, ("%s: sockbuf %p isn't TLS RX",
1830 	    __func__, sb));
1831 	so = __containerof(sb, struct socket, so_rcv);
1832 
1833 	tls = sb->sb_tls_info;
1834 	if_rele(tls->rx_ifp);
1835 	if_ref(ifp);
1836 	tls->rx_ifp = ifp;
1837 
1838 	/*
1839 	 * See if we should schedule a task to update the receive tag for
1840 	 * this session.
1841 	 */
1842 	mtx_pool_lock(mtxpool_sleep, tls);
1843 	if (!tls->reset_pending) {
1844 		(void) ktls_hold(tls);
1845 		soref(so);
1846 		tls->so = so;
1847 		tls->reset_pending = true;
1848 		taskqueue_enqueue(taskqueue_thread, &tls->reset_tag_task);
1849 	}
1850 	mtx_pool_unlock(mtxpool_sleep, tls);
1851 }
1852 
1853 int
ktls_output_eagain(struct inpcb * inp,struct ktls_session * tls)1854 ktls_output_eagain(struct inpcb *inp, struct ktls_session *tls)
1855 {
1856 
1857 	if (inp == NULL)
1858 		return (ENOBUFS);
1859 
1860 	INP_LOCK_ASSERT(inp);
1861 
1862 	/*
1863 	 * See if we should schedule a task to update the send tag for
1864 	 * this session.
1865 	 */
1866 	mtx_pool_lock(mtxpool_sleep, tls);
1867 	if (!tls->reset_pending) {
1868 		(void) ktls_hold(tls);
1869 		tls->reset_pending = true;
1870 		taskqueue_enqueue(taskqueue_thread, &tls->reset_tag_task);
1871 	}
1872 	mtx_pool_unlock(mtxpool_sleep, tls);
1873 	return (ENOBUFS);
1874 }
1875 
1876 #ifdef RATELIMIT
1877 int
ktls_modify_txrtlmt(struct ktls_session * tls,uint64_t max_pacing_rate)1878 ktls_modify_txrtlmt(struct ktls_session *tls, uint64_t max_pacing_rate)
1879 {
1880 	union if_snd_tag_modify_params params = {
1881 		.rate_limit.max_rate = max_pacing_rate,
1882 		.rate_limit.flags = M_NOWAIT,
1883 	};
1884 	struct m_snd_tag *mst;
1885 
1886 	/* Can't get to the inp, but it should be locked. */
1887 	/* INP_LOCK_ASSERT(inp); */
1888 
1889 	MPASS(tls->mode == TCP_TLS_MODE_IFNET);
1890 
1891 	if (tls->snd_tag == NULL) {
1892 		/*
1893 		 * Resetting send tag, ignore this change.  The
1894 		 * pending reset may or may not see this updated rate
1895 		 * in the tcpcb.  If it doesn't, we will just lose
1896 		 * this rate change.
1897 		 */
1898 		return (0);
1899 	}
1900 
1901 	mst = tls->snd_tag;
1902 
1903 	MPASS(mst != NULL);
1904 	MPASS(mst->sw->type == IF_SND_TAG_TYPE_TLS_RATE_LIMIT);
1905 
1906 	return (mst->sw->snd_tag_modify(mst, &params));
1907 }
1908 #endif
1909 
1910 static void
ktls_destroy_help(void * context,int pending __unused)1911 ktls_destroy_help(void *context, int pending __unused)
1912 {
1913 	ktls_destroy(context);
1914 }
1915 
1916 void
ktls_destroy(struct ktls_session * tls)1917 ktls_destroy(struct ktls_session *tls)
1918 {
1919 	struct inpcb *inp;
1920 	struct tcpcb *tp;
1921 	bool wlocked;
1922 
1923 	MPASS(tls->refcount == 0);
1924 
1925 	inp = tls->inp;
1926 	if (tls->tx) {
1927 		wlocked = INP_WLOCKED(inp);
1928 		if (!wlocked && !INP_TRY_WLOCK(inp)) {
1929 			/*
1930 			 * rwlocks read locks are anonymous, and there
1931 			 * is no way to know if our current thread
1932 			 * holds an rlock on the inp.  As a rough
1933 			 * estimate, check to see if the thread holds
1934 			 * *any* rlocks at all.  If it does not, then we
1935 			 * know that we don't hold the inp rlock, and
1936 			 * can safely take the wlock
1937 			 */
1938 			if (curthread->td_rw_rlocks == 0) {
1939 				INP_WLOCK(inp);
1940 			} else {
1941 				/*
1942 				 * We might hold the rlock, so let's
1943 				 * do the destroy in a taskqueue
1944 				 * context to avoid a potential
1945 				 * deadlock.  This should be very
1946 				 * rare.
1947 				 */
1948 				counter_u64_add(ktls_destroy_task, 1);
1949 				TASK_INIT(&tls->destroy_task, 0,
1950 				    ktls_destroy_help, tls);
1951 				(void)taskqueue_enqueue(taskqueue_thread,
1952 				    &tls->destroy_task);
1953 				return;
1954 			}
1955 		}
1956 	}
1957 
1958 	if (tls->sequential_records) {
1959 		struct mbuf *m, *n;
1960 		int page_count;
1961 
1962 		STAILQ_FOREACH_SAFE(m, &tls->pending_records, m_epg_stailq, n) {
1963 			page_count = m->m_epg_enc_cnt;
1964 			while (page_count > 0) {
1965 				KASSERT(page_count >= m->m_epg_nrdy,
1966 				    ("%s: too few pages", __func__));
1967 				page_count -= m->m_epg_nrdy;
1968 				m = m_free(m);
1969 			}
1970 		}
1971 	}
1972 
1973 	counter_u64_add(ktls_offload_active, -1);
1974 	switch (tls->mode) {
1975 	case TCP_TLS_MODE_SW:
1976 		switch (tls->params.cipher_algorithm) {
1977 		case CRYPTO_AES_CBC:
1978 			counter_u64_add(ktls_sw_cbc, -1);
1979 			break;
1980 		case CRYPTO_AES_NIST_GCM_16:
1981 			counter_u64_add(ktls_sw_gcm, -1);
1982 			break;
1983 		case CRYPTO_CHACHA20_POLY1305:
1984 			counter_u64_add(ktls_sw_chacha20, -1);
1985 			break;
1986 		}
1987 		break;
1988 	case TCP_TLS_MODE_IFNET:
1989 		switch (tls->params.cipher_algorithm) {
1990 		case CRYPTO_AES_CBC:
1991 			counter_u64_add(ktls_ifnet_cbc, -1);
1992 			break;
1993 		case CRYPTO_AES_NIST_GCM_16:
1994 			counter_u64_add(ktls_ifnet_gcm, -1);
1995 			break;
1996 		case CRYPTO_CHACHA20_POLY1305:
1997 			counter_u64_add(ktls_ifnet_chacha20, -1);
1998 			break;
1999 		}
2000 		if (tls->snd_tag != NULL)
2001 			m_snd_tag_rele(tls->snd_tag);
2002 		if (tls->rx_ifp != NULL)
2003 			if_rele(tls->rx_ifp);
2004 		if (tls->tx) {
2005 			INP_WLOCK_ASSERT(inp);
2006 			tp = intotcpcb(inp);
2007 			MPASS(tp->t_nic_ktls_xmit == 1);
2008 			tp->t_nic_ktls_xmit = 0;
2009 		}
2010 		break;
2011 #ifdef TCP_OFFLOAD
2012 	case TCP_TLS_MODE_TOE:
2013 		switch (tls->params.cipher_algorithm) {
2014 		case CRYPTO_AES_CBC:
2015 			counter_u64_add(ktls_toe_cbc, -1);
2016 			break;
2017 		case CRYPTO_AES_NIST_GCM_16:
2018 			counter_u64_add(ktls_toe_gcm, -1);
2019 			break;
2020 		case CRYPTO_CHACHA20_POLY1305:
2021 			counter_u64_add(ktls_toe_chacha20, -1);
2022 			break;
2023 		}
2024 		break;
2025 #endif
2026 	}
2027 	if (tls->ocf_session != NULL)
2028 		ktls_ocf_free(tls);
2029 	if (tls->params.auth_key != NULL) {
2030 		zfree(tls->params.auth_key, M_KTLS);
2031 		tls->params.auth_key = NULL;
2032 		tls->params.auth_key_len = 0;
2033 	}
2034 	if (tls->params.cipher_key != NULL) {
2035 		zfree(tls->params.cipher_key, M_KTLS);
2036 		tls->params.cipher_key = NULL;
2037 		tls->params.cipher_key_len = 0;
2038 	}
2039 	if (tls->tx) {
2040 		INP_WLOCK_ASSERT(inp);
2041 		if (!in_pcbrele_wlocked(inp) && !wlocked)
2042 			INP_WUNLOCK(inp);
2043 	}
2044 	explicit_bzero(tls->params.iv, sizeof(tls->params.iv));
2045 
2046 	uma_zfree(ktls_session_zone, tls);
2047 }
2048 
2049 void
ktls_seq(struct sockbuf * sb,struct mbuf * m)2050 ktls_seq(struct sockbuf *sb, struct mbuf *m)
2051 {
2052 
2053 	for (; m != NULL; m = m->m_next) {
2054 		KASSERT((m->m_flags & M_EXTPG) != 0,
2055 		    ("ktls_seq: mapped mbuf %p", m));
2056 
2057 		m->m_epg_seqno = sb->sb_tls_seqno;
2058 		sb->sb_tls_seqno++;
2059 	}
2060 }
2061 
2062 /*
2063  * Add TLS framing (headers and trailers) to a chain of mbufs.  Each
2064  * mbuf in the chain must be an unmapped mbuf.  The payload of the
2065  * mbuf must be populated with the payload of each TLS record.
2066  *
2067  * The record_type argument specifies the TLS record type used when
2068  * populating the TLS header.
2069  *
2070  * The enq_count argument on return is set to the number of pages of
2071  * payload data for this entire chain that need to be encrypted via SW
2072  * encryption.  The returned value should be passed to ktls_enqueue
2073  * when scheduling encryption of this chain of mbufs.  To handle the
2074  * special case of empty fragments for TLS 1.0 sessions, an empty
2075  * fragment counts as one page.
2076  */
2077 void
ktls_frame(struct mbuf * top,struct ktls_session * tls,int * enq_cnt,uint8_t record_type)2078 ktls_frame(struct mbuf *top, struct ktls_session *tls, int *enq_cnt,
2079     uint8_t record_type)
2080 {
2081 	struct tls_record_layer *tlshdr;
2082 	struct mbuf *m;
2083 	uint64_t *noncep;
2084 	uint16_t tls_len;
2085 	int maxlen __diagused;
2086 
2087 	maxlen = tls->params.max_frame_len;
2088 	*enq_cnt = 0;
2089 	for (m = top; m != NULL; m = m->m_next) {
2090 		/*
2091 		 * All mbufs in the chain should be TLS records whose
2092 		 * payload does not exceed the maximum frame length.
2093 		 *
2094 		 * Empty TLS 1.0 records are permitted when using CBC.
2095 		 */
2096 		KASSERT(m->m_len <= maxlen && m->m_len >= 0 &&
2097 		    (m->m_len > 0 || ktls_permit_empty_frames(tls)),
2098 		    ("ktls_frame: m %p len %d", m, m->m_len));
2099 
2100 		/*
2101 		 * TLS frames require unmapped mbufs to store session
2102 		 * info.
2103 		 */
2104 		KASSERT((m->m_flags & M_EXTPG) != 0,
2105 		    ("ktls_frame: mapped mbuf %p (top = %p)", m, top));
2106 
2107 		tls_len = m->m_len;
2108 
2109 		/* Save a reference to the session. */
2110 		m->m_epg_tls = ktls_hold(tls);
2111 
2112 		m->m_epg_hdrlen = tls->params.tls_hlen;
2113 		m->m_epg_trllen = tls->params.tls_tlen;
2114 		if (tls->params.cipher_algorithm == CRYPTO_AES_CBC) {
2115 			int bs, delta;
2116 
2117 			/*
2118 			 * AES-CBC pads messages to a multiple of the
2119 			 * block size.  Note that the padding is
2120 			 * applied after the digest and the encryption
2121 			 * is done on the "plaintext || mac || padding".
2122 			 * At least one byte of padding is always
2123 			 * present.
2124 			 *
2125 			 * Compute the final trailer length assuming
2126 			 * at most one block of padding.
2127 			 * tls->params.tls_tlen is the maximum
2128 			 * possible trailer length (padding + digest).
2129 			 * delta holds the number of excess padding
2130 			 * bytes if the maximum were used.  Those
2131 			 * extra bytes are removed.
2132 			 */
2133 			bs = tls->params.tls_bs;
2134 			delta = (tls_len + tls->params.tls_tlen) & (bs - 1);
2135 			m->m_epg_trllen -= delta;
2136 		}
2137 		m->m_len += m->m_epg_hdrlen + m->m_epg_trllen;
2138 
2139 		/* Populate the TLS header. */
2140 		tlshdr = (void *)m->m_epg_hdr;
2141 		tlshdr->tls_vmajor = tls->params.tls_vmajor;
2142 
2143 		/*
2144 		 * TLS 1.3 masquarades as TLS 1.2 with a record type
2145 		 * of TLS_RLTYPE_APP.
2146 		 */
2147 		if (tls->params.tls_vminor == TLS_MINOR_VER_THREE &&
2148 		    tls->params.tls_vmajor == TLS_MAJOR_VER_ONE) {
2149 			tlshdr->tls_vminor = TLS_MINOR_VER_TWO;
2150 			tlshdr->tls_type = TLS_RLTYPE_APP;
2151 			/* save the real record type for later */
2152 			m->m_epg_record_type = record_type;
2153 			m->m_epg_trail[0] = record_type;
2154 		} else {
2155 			tlshdr->tls_vminor = tls->params.tls_vminor;
2156 			tlshdr->tls_type = record_type;
2157 		}
2158 		tlshdr->tls_length = htons(m->m_len - sizeof(*tlshdr));
2159 
2160 		/*
2161 		 * Store nonces / explicit IVs after the end of the
2162 		 * TLS header.
2163 		 *
2164 		 * For GCM with TLS 1.2, an 8 byte nonce is copied
2165 		 * from the end of the IV.  The nonce is then
2166 		 * incremented for use by the next record.
2167 		 *
2168 		 * For CBC, a random nonce is inserted for TLS 1.1+.
2169 		 */
2170 		if (tls->params.cipher_algorithm == CRYPTO_AES_NIST_GCM_16 &&
2171 		    tls->params.tls_vminor == TLS_MINOR_VER_TWO) {
2172 			noncep = (uint64_t *)(tls->params.iv + 8);
2173 			be64enc(tlshdr + 1, *noncep);
2174 			(*noncep)++;
2175 		} else if (tls->params.cipher_algorithm == CRYPTO_AES_CBC &&
2176 		    tls->params.tls_vminor >= TLS_MINOR_VER_ONE)
2177 			arc4rand(tlshdr + 1, AES_BLOCK_LEN, 0);
2178 
2179 		/*
2180 		 * When using SW encryption, mark the mbuf not ready.
2181 		 * It will be marked ready via sbready() after the
2182 		 * record has been encrypted.
2183 		 *
2184 		 * When using ifnet TLS, unencrypted TLS records are
2185 		 * sent down the stack to the NIC.
2186 		 */
2187 		if (tls->mode == TCP_TLS_MODE_SW) {
2188 			m->m_flags |= M_NOTREADY;
2189 			if (__predict_false(tls_len == 0)) {
2190 				/* TLS 1.0 empty fragment. */
2191 				m->m_epg_nrdy = 1;
2192 			} else
2193 				m->m_epg_nrdy = m->m_epg_npgs;
2194 			*enq_cnt += m->m_epg_nrdy;
2195 		}
2196 	}
2197 }
2198 
2199 bool
ktls_permit_empty_frames(struct ktls_session * tls)2200 ktls_permit_empty_frames(struct ktls_session *tls)
2201 {
2202 	return (tls->params.cipher_algorithm == CRYPTO_AES_CBC &&
2203 	    tls->params.tls_vminor == TLS_MINOR_VER_ZERO);
2204 }
2205 
2206 void
ktls_check_rx(struct sockbuf * sb)2207 ktls_check_rx(struct sockbuf *sb)
2208 {
2209 	struct tls_record_layer hdr;
2210 	struct ktls_wq *wq;
2211 	struct socket *so;
2212 	bool running;
2213 
2214 	SOCKBUF_LOCK_ASSERT(sb);
2215 	KASSERT(sb->sb_flags & SB_TLS_RX, ("%s: sockbuf %p isn't TLS RX",
2216 	    __func__, sb));
2217 	so = __containerof(sb, struct socket, so_rcv);
2218 
2219 	if (sb->sb_flags & SB_TLS_RX_RUNNING)
2220 		return;
2221 
2222 	/* Is there enough queued for a TLS header? */
2223 	if (sb->sb_tlscc < sizeof(hdr)) {
2224 		if ((sb->sb_state & SBS_CANTRCVMORE) != 0 && sb->sb_tlscc != 0)
2225 			so->so_error = EMSGSIZE;
2226 		return;
2227 	}
2228 
2229 	m_copydata(sb->sb_mtls, 0, sizeof(hdr), (void *)&hdr);
2230 
2231 	/* Is the entire record queued? */
2232 	if (sb->sb_tlscc < sizeof(hdr) + ntohs(hdr.tls_length)) {
2233 		if ((sb->sb_state & SBS_CANTRCVMORE) != 0)
2234 			so->so_error = EMSGSIZE;
2235 		return;
2236 	}
2237 
2238 	sb->sb_flags |= SB_TLS_RX_RUNNING;
2239 
2240 	soref(so);
2241 	wq = &ktls_wq[so->so_rcv.sb_tls_info->wq_index];
2242 	mtx_lock(&wq->mtx);
2243 	STAILQ_INSERT_TAIL(&wq->so_head, so, so_ktls_rx_list);
2244 	running = wq->running;
2245 	mtx_unlock(&wq->mtx);
2246 	if (!running)
2247 		wakeup(wq);
2248 	counter_u64_add(ktls_cnt_rx_queued, 1);
2249 }
2250 
2251 static struct mbuf *
ktls_detach_record(struct sockbuf * sb,int len)2252 ktls_detach_record(struct sockbuf *sb, int len)
2253 {
2254 	struct mbuf *m, *n, *top;
2255 	int remain;
2256 
2257 	SOCKBUF_LOCK_ASSERT(sb);
2258 	MPASS(len <= sb->sb_tlscc);
2259 
2260 	/*
2261 	 * If TLS chain is the exact size of the record,
2262 	 * just grab the whole record.
2263 	 */
2264 	top = sb->sb_mtls;
2265 	if (sb->sb_tlscc == len) {
2266 		sb->sb_mtls = NULL;
2267 		sb->sb_mtlstail = NULL;
2268 		goto out;
2269 	}
2270 
2271 	/*
2272 	 * While it would be nice to use m_split() here, we need
2273 	 * to know exactly what m_split() allocates to update the
2274 	 * accounting, so do it inline instead.
2275 	 */
2276 	remain = len;
2277 	for (m = top; remain > m->m_len; m = m->m_next)
2278 		remain -= m->m_len;
2279 
2280 	/* Easy case: don't have to split 'm'. */
2281 	if (remain == m->m_len) {
2282 		sb->sb_mtls = m->m_next;
2283 		if (sb->sb_mtls == NULL)
2284 			sb->sb_mtlstail = NULL;
2285 		m->m_next = NULL;
2286 		goto out;
2287 	}
2288 
2289 	/*
2290 	 * Need to allocate an mbuf to hold the remainder of 'm'.  Try
2291 	 * with M_NOWAIT first.
2292 	 */
2293 	n = m_get(M_NOWAIT, MT_DATA);
2294 	if (n == NULL) {
2295 		/*
2296 		 * Use M_WAITOK with socket buffer unlocked.  If
2297 		 * 'sb_mtls' changes while the lock is dropped, return
2298 		 * NULL to force the caller to retry.
2299 		 */
2300 		SOCKBUF_UNLOCK(sb);
2301 
2302 		n = m_get(M_WAITOK, MT_DATA);
2303 
2304 		SOCKBUF_LOCK(sb);
2305 		if (sb->sb_mtls != top) {
2306 			m_free(n);
2307 			return (NULL);
2308 		}
2309 	}
2310 	n->m_flags |= (m->m_flags & (M_NOTREADY | M_DECRYPTED));
2311 
2312 	/* Store remainder in 'n'. */
2313 	n->m_len = m->m_len - remain;
2314 	if (m->m_flags & M_EXT) {
2315 		n->m_data = m->m_data + remain;
2316 		mb_dupcl(n, m);
2317 	} else {
2318 		bcopy(mtod(m, caddr_t) + remain, mtod(n, caddr_t), n->m_len);
2319 	}
2320 
2321 	/* Trim 'm' and update accounting. */
2322 	m->m_len -= n->m_len;
2323 	sb->sb_tlscc -= n->m_len;
2324 	sb->sb_ccc -= n->m_len;
2325 
2326 	/* Account for 'n'. */
2327 	sballoc_ktls_rx(sb, n);
2328 
2329 	/* Insert 'n' into the TLS chain. */
2330 	sb->sb_mtls = n;
2331 	n->m_next = m->m_next;
2332 	if (sb->sb_mtlstail == m)
2333 		sb->sb_mtlstail = n;
2334 
2335 	/* Detach the record from the TLS chain. */
2336 	m->m_next = NULL;
2337 
2338 out:
2339 	MPASS(m_length(top, NULL) == len);
2340 	for (m = top; m != NULL; m = m->m_next)
2341 		sbfree_ktls_rx(sb, m);
2342 	sb->sb_tlsdcc = len;
2343 	sb->sb_ccc += len;
2344 	SBCHECK(sb);
2345 	return (top);
2346 }
2347 
2348 /*
2349  * Determine the length of the trailing zero padding and find the real
2350  * record type in the byte before the padding.
2351  *
2352  * Walking the mbuf chain backwards is clumsy, so another option would
2353  * be to scan forwards remembering the last non-zero byte before the
2354  * trailer.  However, it would be expensive to scan the entire record.
2355  * Instead, find the last non-zero byte of each mbuf in the chain
2356  * keeping track of the relative offset of that nonzero byte.
2357  *
2358  * trail_len is the size of the MAC/tag on input and is set to the
2359  * size of the full trailer including padding and the record type on
2360  * return.
2361  */
2362 static int
tls13_find_record_type(struct ktls_session * tls,struct mbuf * m,int tls_len,int * trailer_len,uint8_t * record_typep)2363 tls13_find_record_type(struct ktls_session *tls, struct mbuf *m, int tls_len,
2364     int *trailer_len, uint8_t *record_typep)
2365 {
2366 	char *cp;
2367 	u_int digest_start, last_offset, m_len, offset;
2368 	uint8_t record_type;
2369 
2370 	digest_start = tls_len - *trailer_len;
2371 	last_offset = 0;
2372 	offset = 0;
2373 	for (; m != NULL && offset < digest_start;
2374 	     offset += m->m_len, m = m->m_next) {
2375 		/* Don't look for padding in the tag. */
2376 		m_len = min(digest_start - offset, m->m_len);
2377 		cp = mtod(m, char *);
2378 
2379 		/* Find last non-zero byte in this mbuf. */
2380 		while (m_len > 0 && cp[m_len - 1] == 0)
2381 			m_len--;
2382 		if (m_len > 0) {
2383 			record_type = cp[m_len - 1];
2384 			last_offset = offset + m_len;
2385 		}
2386 	}
2387 	if (last_offset < tls->params.tls_hlen)
2388 		return (EBADMSG);
2389 
2390 	*record_typep = record_type;
2391 	*trailer_len = tls_len - last_offset + 1;
2392 	return (0);
2393 }
2394 
2395 /*
2396  * Check if a mbuf chain is fully decrypted at the given offset and
2397  * length. Returns KTLS_MBUF_CRYPTO_ST_DECRYPTED if all data is
2398  * decrypted. KTLS_MBUF_CRYPTO_ST_MIXED if there is a mix of encrypted
2399  * and decrypted data. Else KTLS_MBUF_CRYPTO_ST_ENCRYPTED if all data
2400  * is encrypted.
2401  */
2402 ktls_mbuf_crypto_st_t
ktls_mbuf_crypto_state(struct mbuf * mb,int offset,int len)2403 ktls_mbuf_crypto_state(struct mbuf *mb, int offset, int len)
2404 {
2405 	int m_flags_ored = 0;
2406 	int m_flags_anded = -1;
2407 
2408 	for (; mb != NULL; mb = mb->m_next) {
2409 		if (offset < mb->m_len)
2410 			break;
2411 		offset -= mb->m_len;
2412 	}
2413 	offset += len;
2414 
2415 	for (; mb != NULL; mb = mb->m_next) {
2416 		m_flags_ored |= mb->m_flags;
2417 		m_flags_anded &= mb->m_flags;
2418 
2419 		if (offset <= mb->m_len)
2420 			break;
2421 		offset -= mb->m_len;
2422 	}
2423 	MPASS(mb != NULL || offset == 0);
2424 
2425 	if ((m_flags_ored ^ m_flags_anded) & M_DECRYPTED)
2426 		return (KTLS_MBUF_CRYPTO_ST_MIXED);
2427 	else
2428 		return ((m_flags_ored & M_DECRYPTED) ?
2429 		    KTLS_MBUF_CRYPTO_ST_DECRYPTED :
2430 		    KTLS_MBUF_CRYPTO_ST_ENCRYPTED);
2431 }
2432 
2433 /*
2434  * ktls_resync_ifnet - get HW TLS RX back on track after packet loss
2435  */
2436 static int
ktls_resync_ifnet(struct socket * so,uint32_t tls_len,uint64_t tls_rcd_num)2437 ktls_resync_ifnet(struct socket *so, uint32_t tls_len, uint64_t tls_rcd_num)
2438 {
2439 	union if_snd_tag_modify_params params;
2440 	struct m_snd_tag *mst;
2441 	struct inpcb *inp = sotoinpcb(so);
2442 	struct tcpcb *tp = intotcpcb(inp);
2443 
2444 	mst = so->so_rcv.sb_tls_info->snd_tag;
2445 	if (__predict_false(mst == NULL))
2446 		return (EINVAL);
2447 
2448 	INP_RLOCK(inp);
2449 	if (tp->t_flags & TF_DISCONNECTED) {
2450 		INP_RUNLOCK(inp);
2451 		return (ECONNRESET);
2452 	}
2453 
2454 	/* Get the TCP sequence number of the next valid TLS header. */
2455 	SOCKBUF_LOCK(&so->so_rcv);
2456 	params.tls_rx.tls_hdr_tcp_sn =
2457 	    tp->rcv_nxt - so->so_rcv.sb_tlscc - tls_len;
2458 	params.tls_rx.tls_rec_length = tls_len;
2459 	params.tls_rx.tls_seq_number = tls_rcd_num;
2460 	SOCKBUF_UNLOCK(&so->so_rcv);
2461 
2462 	INP_RUNLOCK(inp);
2463 
2464 	MPASS(mst->sw->type == IF_SND_TAG_TYPE_TLS_RX);
2465 	return (mst->sw->snd_tag_modify(mst, &params));
2466 }
2467 
2468 static void
ktls_drop(struct socket * so,int error)2469 ktls_drop(struct socket *so, int error)
2470 {
2471 	struct epoch_tracker et;
2472 	struct inpcb *inp = sotoinpcb(so);
2473 	struct tcpcb *tp = intotcpcb(inp);
2474 
2475 	NET_EPOCH_ENTER(et);
2476 	INP_WLOCK(inp);
2477 	if (!(tp->t_flags & TF_DISCONNECTED)) {
2478 		CURVNET_SET(inp->inp_socket->so_vnet);
2479 		tp = tcp_drop(tp, error);
2480 		CURVNET_RESTORE();
2481 		if (tp != NULL)
2482 			INP_WUNLOCK(inp);
2483 	} else {
2484 		so->so_error = error;
2485 		SOCK_RECVBUF_LOCK(so);
2486 		sorwakeup_locked(so);
2487 		INP_WUNLOCK(inp);
2488 	}
2489 	NET_EPOCH_EXIT(et);
2490 }
2491 
2492 static void
ktls_decrypt(struct socket * so)2493 ktls_decrypt(struct socket *so)
2494 {
2495 	char tls_header[MBUF_PEXT_HDR_LEN];
2496 	struct ktls_session *tls;
2497 	struct sockbuf *sb;
2498 	struct tls_record_layer *hdr;
2499 	struct tls_get_record tgr;
2500 	struct mbuf *control, *data, *m;
2501 	ktls_mbuf_crypto_st_t state;
2502 	uint64_t seqno;
2503 	int error, remain, tls_len, trail_len;
2504 	bool tls13;
2505 	uint8_t vminor, record_type;
2506 
2507 	hdr = (struct tls_record_layer *)tls_header;
2508 	sb = &so->so_rcv;
2509 	SOCKBUF_LOCK(sb);
2510 	KASSERT(sb->sb_flags & SB_TLS_RX_RUNNING,
2511 	    ("%s: socket %p not running", __func__, so));
2512 
2513 	tls = sb->sb_tls_info;
2514 	MPASS(tls != NULL);
2515 
2516 	tls13 = (tls->params.tls_vminor == TLS_MINOR_VER_THREE);
2517 	if (tls13)
2518 		vminor = TLS_MINOR_VER_TWO;
2519 	else
2520 		vminor = tls->params.tls_vminor;
2521 	for (;;) {
2522 		/* Is there enough queued for a TLS header? */
2523 		if (sb->sb_tlscc < tls->params.tls_hlen)
2524 			break;
2525 
2526 		m_copydata(sb->sb_mtls, 0, tls->params.tls_hlen, tls_header);
2527 		tls_len = sizeof(*hdr) + ntohs(hdr->tls_length);
2528 
2529 		if (hdr->tls_vmajor != tls->params.tls_vmajor ||
2530 		    hdr->tls_vminor != vminor)
2531 			error = EINVAL;
2532 		else if (tls13 && hdr->tls_type != TLS_RLTYPE_APP)
2533 			error = EINVAL;
2534 		else if (tls_len < tls->params.tls_hlen || tls_len >
2535 		    tls->params.tls_hlen + TLS_MAX_MSG_SIZE_V10_2 +
2536 		    tls->params.tls_tlen)
2537 			error = EMSGSIZE;
2538 		else
2539 			error = 0;
2540 		if (__predict_false(error != 0)) {
2541 			/*
2542 			 * We have a corrupted record and are likely
2543 			 * out of sync.  The connection isn't
2544 			 * recoverable at this point, so abort it.
2545 			 */
2546 			SOCKBUF_UNLOCK(sb);
2547 			counter_u64_add(ktls_offload_corrupted_records, 1);
2548 
2549 			ktls_drop(so, error);
2550 			goto deref;
2551 		}
2552 
2553 		/* Is the entire record queued? */
2554 		if (sb->sb_tlscc < tls_len)
2555 			break;
2556 
2557 		/*
2558 		 * Split out the portion of the mbuf chain containing
2559 		 * this TLS record.
2560 		 */
2561 		data = ktls_detach_record(sb, tls_len);
2562 		if (data == NULL)
2563 			continue;
2564 		MPASS(sb->sb_tlsdcc == tls_len);
2565 
2566 		seqno = sb->sb_tls_seqno;
2567 		sb->sb_tls_seqno++;
2568 		SBCHECK(sb);
2569 		SOCKBUF_UNLOCK(sb);
2570 
2571 		/* get crypto state for this TLS record */
2572 		state = ktls_mbuf_crypto_state(data, 0, tls_len);
2573 
2574 		switch (state) {
2575 		case KTLS_MBUF_CRYPTO_ST_MIXED:
2576 			error = ktls_ocf_recrypt(tls, hdr, data, seqno);
2577 			if (error)
2578 				break;
2579 			/* FALLTHROUGH */
2580 		case KTLS_MBUF_CRYPTO_ST_ENCRYPTED:
2581 			error = ktls_ocf_decrypt(tls, hdr, data, seqno,
2582 			    &trail_len);
2583 			if (__predict_true(error == 0)) {
2584 				if (tls13) {
2585 					error = tls13_find_record_type(tls, data,
2586 					    tls_len, &trail_len, &record_type);
2587 				} else {
2588 					record_type = hdr->tls_type;
2589 				}
2590 			}
2591 			break;
2592 		case KTLS_MBUF_CRYPTO_ST_DECRYPTED:
2593 			/*
2594 			 * NIC TLS is only supported for AEAD
2595 			 * ciphersuites which used a fixed sized
2596 			 * trailer.
2597 			 */
2598 			if (tls13) {
2599 				trail_len = tls->params.tls_tlen - 1;
2600 				error = tls13_find_record_type(tls, data,
2601 				    tls_len, &trail_len, &record_type);
2602 			} else {
2603 				trail_len = tls->params.tls_tlen;
2604 				error = 0;
2605 				record_type = hdr->tls_type;
2606 			}
2607 			break;
2608 		default:
2609 			error = EINVAL;
2610 			break;
2611 		}
2612 		if (error) {
2613 			counter_u64_add(ktls_offload_failed_crypto, 1);
2614 
2615 			SOCKBUF_LOCK(sb);
2616 			if (sb->sb_tlsdcc == 0) {
2617 				/*
2618 				 * sbcut/drop/flush discarded these
2619 				 * mbufs.
2620 				 */
2621 				m_freem(data);
2622 				break;
2623 			}
2624 
2625 			/*
2626 			 * Drop this TLS record's data, but keep
2627 			 * decrypting subsequent records.
2628 			 */
2629 			sb->sb_ccc -= tls_len;
2630 			sb->sb_tlsdcc = 0;
2631 
2632 			if (error != EMSGSIZE)
2633 				error = EBADMSG;
2634 			CURVNET_SET(so->so_vnet);
2635 			so->so_error = error;
2636 			sorwakeup_locked(so);
2637 			CURVNET_RESTORE();
2638 
2639 			m_freem(data);
2640 
2641 			SOCKBUF_LOCK(sb);
2642 			continue;
2643 		}
2644 
2645 		/* Allocate the control mbuf. */
2646 		memset(&tgr, 0, sizeof(tgr));
2647 		tgr.tls_type = record_type;
2648 		tgr.tls_vmajor = hdr->tls_vmajor;
2649 		tgr.tls_vminor = hdr->tls_vminor;
2650 		tgr.tls_length = htobe16(tls_len - tls->params.tls_hlen -
2651 		    trail_len);
2652 		control = sbcreatecontrol(&tgr, sizeof(tgr),
2653 		    TLS_GET_RECORD, IPPROTO_TCP, M_WAITOK);
2654 
2655 		SOCKBUF_LOCK(sb);
2656 		if (sb->sb_tlsdcc == 0) {
2657 			/* sbcut/drop/flush discarded these mbufs. */
2658 			MPASS(sb->sb_tlscc == 0);
2659 			m_freem(data);
2660 			m_freem(control);
2661 			break;
2662 		}
2663 
2664 		/*
2665 		 * Clear the 'dcc' accounting in preparation for
2666 		 * adding the decrypted record.
2667 		 */
2668 		sb->sb_ccc -= tls_len;
2669 		sb->sb_tlsdcc = 0;
2670 		SBCHECK(sb);
2671 
2672 		/* If there is no payload, drop all of the data. */
2673 		if (tgr.tls_length == htobe16(0)) {
2674 			m_freem(data);
2675 			data = NULL;
2676 		} else {
2677 			/* Trim header. */
2678 			remain = tls->params.tls_hlen;
2679 			while (remain > 0) {
2680 				if (data->m_len > remain) {
2681 					data->m_data += remain;
2682 					data->m_len -= remain;
2683 					break;
2684 				}
2685 				remain -= data->m_len;
2686 				data = m_free(data);
2687 			}
2688 
2689 			/* Trim trailer and clear M_NOTREADY. */
2690 			remain = be16toh(tgr.tls_length);
2691 			m = data;
2692 			for (m = data; remain > m->m_len; m = m->m_next) {
2693 				m->m_flags &= ~(M_NOTREADY | M_DECRYPTED);
2694 				remain -= m->m_len;
2695 			}
2696 			m->m_len = remain;
2697 			m_freem(m->m_next);
2698 			m->m_next = NULL;
2699 			m->m_flags &= ~(M_NOTREADY | M_DECRYPTED);
2700 
2701 			/* Set EOR on the final mbuf. */
2702 			m->m_flags |= M_EOR;
2703 		}
2704 
2705 		sbappendcontrol_locked(sb, data, control, 0);
2706 
2707 		if (__predict_false(state != KTLS_MBUF_CRYPTO_ST_DECRYPTED)) {
2708 			sb->sb_flags |= SB_TLS_RX_RESYNC;
2709 			SOCKBUF_UNLOCK(sb);
2710 			ktls_resync_ifnet(so, tls_len, seqno);
2711 			SOCKBUF_LOCK(sb);
2712 		} else if (__predict_false(sb->sb_flags & SB_TLS_RX_RESYNC)) {
2713 			sb->sb_flags &= ~SB_TLS_RX_RESYNC;
2714 			SOCKBUF_UNLOCK(sb);
2715 			ktls_resync_ifnet(so, 0, seqno);
2716 			SOCKBUF_LOCK(sb);
2717 		}
2718 	}
2719 
2720 	sb->sb_flags &= ~SB_TLS_RX_RUNNING;
2721 
2722 	if ((sb->sb_state & SBS_CANTRCVMORE) != 0 && sb->sb_tlscc > 0)
2723 		so->so_error = EMSGSIZE;
2724 
2725 	sorwakeup_locked(so);
2726 
2727 deref:
2728 	SOCKBUF_UNLOCK_ASSERT(sb);
2729 
2730 	CURVNET_SET(so->so_vnet);
2731 	sorele(so);
2732 	CURVNET_RESTORE();
2733 }
2734 
2735 void
ktls_enqueue_to_free(struct mbuf * m)2736 ktls_enqueue_to_free(struct mbuf *m)
2737 {
2738 	struct ktls_wq *wq;
2739 	bool running;
2740 
2741 	/* Mark it for freeing. */
2742 	m->m_epg_flags |= EPG_FLAG_2FREE;
2743 	wq = &ktls_wq[m->m_epg_tls->wq_index];
2744 	mtx_lock(&wq->mtx);
2745 	STAILQ_INSERT_TAIL(&wq->m_head, m, m_epg_stailq);
2746 	running = wq->running;
2747 	mtx_unlock(&wq->mtx);
2748 	if (!running)
2749 		wakeup(wq);
2750 }
2751 
2752 static void *
ktls_buffer_alloc(struct ktls_wq * wq,struct mbuf * m)2753 ktls_buffer_alloc(struct ktls_wq *wq, struct mbuf *m)
2754 {
2755 	void *buf;
2756 	int domain, running;
2757 
2758 	if (m->m_epg_npgs <= 2)
2759 		return (NULL);
2760 	if (ktls_buffer_zone == NULL)
2761 		return (NULL);
2762 	if ((u_int)(ticks - wq->lastallocfail) < hz) {
2763 		/*
2764 		 * Rate-limit allocation attempts after a failure.
2765 		 * ktls_buffer_import() will acquire a per-domain mutex to check
2766 		 * the free page queues and may fail consistently if memory is
2767 		 * fragmented.
2768 		 */
2769 		return (NULL);
2770 	}
2771 	buf = uma_zalloc(ktls_buffer_zone, M_NOWAIT | M_NORECLAIM);
2772 	if (buf == NULL) {
2773 		domain = PCPU_GET(domain);
2774 		wq->lastallocfail = ticks;
2775 
2776 		/*
2777 		 * Note that this check is "racy", but the races are
2778 		 * harmless, and are either a spurious wakeup if
2779 		 * multiple threads fail allocations before the alloc
2780 		 * thread wakes, or waiting an extra second in case we
2781 		 * see an old value of running == true.
2782 		 */
2783 		if (!VM_DOMAIN_EMPTY(domain)) {
2784 			running = atomic_load_int(&ktls_domains[domain].reclaim_td.running);
2785 			if (!running)
2786 				wakeup(&ktls_domains[domain].reclaim_td);
2787 		}
2788 	}
2789 	return (buf);
2790 }
2791 
2792 static int
ktls_encrypt_record(struct ktls_wq * wq,struct mbuf * m,struct ktls_session * tls,struct ktls_ocf_encrypt_state * state)2793 ktls_encrypt_record(struct ktls_wq *wq, struct mbuf *m,
2794     struct ktls_session *tls, struct ktls_ocf_encrypt_state *state)
2795 {
2796 	vm_page_t pg;
2797 	int error, i, len, off;
2798 
2799 	KASSERT((m->m_flags & (M_EXTPG | M_NOTREADY)) == (M_EXTPG | M_NOTREADY),
2800 	    ("%p not unready & nomap mbuf\n", m));
2801 	KASSERT(ptoa(m->m_epg_npgs) <= ktls_maxlen,
2802 	    ("page count %d larger than maximum frame length %d", m->m_epg_npgs,
2803 	    ktls_maxlen));
2804 
2805 	/* Anonymous mbufs are encrypted in place. */
2806 	if ((m->m_epg_flags & EPG_FLAG_ANON) != 0)
2807 		return (ktls_ocf_encrypt(state, tls, m, NULL, 0));
2808 
2809 	/*
2810 	 * For file-backed mbufs (from sendfile), anonymous wired
2811 	 * pages are allocated and used as the encryption destination.
2812 	 */
2813 	if ((state->cbuf = ktls_buffer_alloc(wq, m)) != NULL) {
2814 		len = ptoa(m->m_epg_npgs - 1) + m->m_epg_last_len -
2815 		    m->m_epg_1st_off;
2816 		state->dst_iov[0].iov_base = (char *)state->cbuf +
2817 		    m->m_epg_1st_off;
2818 		state->dst_iov[0].iov_len = len;
2819 		state->parray[0] = DMAP_TO_PHYS(state->cbuf);
2820 		i = 1;
2821 	} else {
2822 		off = m->m_epg_1st_off;
2823 		for (i = 0; i < m->m_epg_npgs; i++, off = 0) {
2824 			pg = vm_page_alloc_noobj(VM_ALLOC_NODUMP |
2825 			    VM_ALLOC_WIRED | VM_ALLOC_WAITOK);
2826 			len = m_epg_pagelen(m, i, off);
2827 			state->parray[i] = VM_PAGE_TO_PHYS(pg);
2828 			state->dst_iov[i].iov_base =
2829 			    (char *)PHYS_TO_DMAP(state->parray[i]) + off;
2830 			state->dst_iov[i].iov_len = len;
2831 		}
2832 	}
2833 	KASSERT(i + 1 <= nitems(state->dst_iov), ("dst_iov is too small"));
2834 	state->dst_iov[i].iov_base = m->m_epg_trail;
2835 	state->dst_iov[i].iov_len = m->m_epg_trllen;
2836 
2837 	error = ktls_ocf_encrypt(state, tls, m, state->dst_iov, i + 1);
2838 
2839 	if (__predict_false(error != 0)) {
2840 		/* Free the anonymous pages. */
2841 		if (state->cbuf != NULL)
2842 			uma_zfree(ktls_buffer_zone, state->cbuf);
2843 		else {
2844 			for (i = 0; i < m->m_epg_npgs; i++) {
2845 				pg = PHYS_TO_VM_PAGE(state->parray[i]);
2846 				(void)vm_page_unwire_noq(pg);
2847 				vm_page_free(pg);
2848 			}
2849 		}
2850 	}
2851 	return (error);
2852 }
2853 
2854 /* Number of TLS records in a batch passed to ktls_enqueue(). */
2855 static u_int
ktls_batched_records(struct mbuf * m)2856 ktls_batched_records(struct mbuf *m)
2857 {
2858 	int page_count, records;
2859 
2860 	records = 0;
2861 	page_count = m->m_epg_enc_cnt;
2862 	while (page_count > 0) {
2863 		records++;
2864 		page_count -= m->m_epg_nrdy;
2865 		m = m->m_next;
2866 	}
2867 	KASSERT(page_count == 0, ("%s: mismatched page count", __func__));
2868 	return (records);
2869 }
2870 
2871 void
ktls_enqueue(struct mbuf * m,struct socket * so,int page_count)2872 ktls_enqueue(struct mbuf *m, struct socket *so, int page_count)
2873 {
2874 	struct ktls_session *tls;
2875 	struct ktls_wq *wq;
2876 	int queued;
2877 	bool running;
2878 
2879 	KASSERT(((m->m_flags & (M_EXTPG | M_NOTREADY)) ==
2880 	    (M_EXTPG | M_NOTREADY)),
2881 	    ("ktls_enqueue: %p not unready & nomap mbuf\n", m));
2882 	KASSERT(page_count != 0, ("enqueueing TLS mbuf with zero page count"));
2883 
2884 	KASSERT(m->m_epg_tls->mode == TCP_TLS_MODE_SW, ("!SW TLS mbuf"));
2885 
2886 	m->m_epg_enc_cnt = page_count;
2887 
2888 	/*
2889 	 * Save a pointer to the socket.  The caller is responsible
2890 	 * for taking an additional reference via soref().
2891 	 */
2892 	m->m_epg_so = so;
2893 
2894 	queued = 1;
2895 	tls = m->m_epg_tls;
2896 	wq = &ktls_wq[tls->wq_index];
2897 	mtx_lock(&wq->mtx);
2898 	if (__predict_false(tls->sequential_records)) {
2899 		/*
2900 		 * For TLS 1.0, records must be encrypted
2901 		 * sequentially.  For a given connection, all records
2902 		 * queued to the associated work queue are processed
2903 		 * sequentially.  However, sendfile(2) might complete
2904 		 * I/O requests spanning multiple TLS records out of
2905 		 * order.  Here we ensure TLS records are enqueued to
2906 		 * the work queue in FIFO order.
2907 		 *
2908 		 * tls->next_seqno holds the sequence number of the
2909 		 * next TLS record that should be enqueued to the work
2910 		 * queue.  If this next record is not tls->next_seqno,
2911 		 * it must be a future record, so insert it, sorted by
2912 		 * TLS sequence number, into tls->pending_records and
2913 		 * return.
2914 		 *
2915 		 * If this TLS record matches tls->next_seqno, place
2916 		 * it in the work queue and then check
2917 		 * tls->pending_records to see if any
2918 		 * previously-queued records are now ready for
2919 		 * encryption.
2920 		 */
2921 		if (m->m_epg_seqno != tls->next_seqno) {
2922 			struct mbuf *n, *p;
2923 
2924 			p = NULL;
2925 			STAILQ_FOREACH(n, &tls->pending_records, m_epg_stailq) {
2926 				if (n->m_epg_seqno > m->m_epg_seqno)
2927 					break;
2928 				p = n;
2929 			}
2930 			if (n == NULL)
2931 				STAILQ_INSERT_TAIL(&tls->pending_records, m,
2932 				    m_epg_stailq);
2933 			else if (p == NULL)
2934 				STAILQ_INSERT_HEAD(&tls->pending_records, m,
2935 				    m_epg_stailq);
2936 			else
2937 				STAILQ_INSERT_AFTER(&tls->pending_records, p, m,
2938 				    m_epg_stailq);
2939 			mtx_unlock(&wq->mtx);
2940 			counter_u64_add(ktls_cnt_tx_pending, 1);
2941 			return;
2942 		}
2943 
2944 		tls->next_seqno += ktls_batched_records(m);
2945 		STAILQ_INSERT_TAIL(&wq->m_head, m, m_epg_stailq);
2946 
2947 		while (!STAILQ_EMPTY(&tls->pending_records)) {
2948 			struct mbuf *n;
2949 
2950 			n = STAILQ_FIRST(&tls->pending_records);
2951 			if (n->m_epg_seqno != tls->next_seqno)
2952 				break;
2953 
2954 			queued++;
2955 			STAILQ_REMOVE_HEAD(&tls->pending_records, m_epg_stailq);
2956 			tls->next_seqno += ktls_batched_records(n);
2957 			STAILQ_INSERT_TAIL(&wq->m_head, n, m_epg_stailq);
2958 		}
2959 		counter_u64_add(ktls_cnt_tx_pending, -(queued - 1));
2960 	} else
2961 		STAILQ_INSERT_TAIL(&wq->m_head, m, m_epg_stailq);
2962 
2963 	running = wq->running;
2964 	mtx_unlock(&wq->mtx);
2965 	if (!running)
2966 		wakeup(wq);
2967 	counter_u64_add(ktls_cnt_tx_queued, queued);
2968 }
2969 
2970 /*
2971  * Once a file-backed mbuf (from sendfile) has been encrypted, free
2972  * the pages from the file and replace them with the anonymous pages
2973  * allocated in ktls_encrypt_record().
2974  */
2975 static void
ktls_finish_nonanon(struct mbuf * m,struct ktls_ocf_encrypt_state * state)2976 ktls_finish_nonanon(struct mbuf *m, struct ktls_ocf_encrypt_state *state)
2977 {
2978 	int i;
2979 
2980 	MPASS((m->m_epg_flags & EPG_FLAG_ANON) == 0);
2981 
2982 	/* Free the old pages. */
2983 	m->m_ext.ext_free(m);
2984 
2985 	/* Replace them with the new pages. */
2986 	if (state->cbuf != NULL) {
2987 		for (i = 0; i < m->m_epg_npgs; i++)
2988 			m->m_epg_pa[i] = state->parray[0] + ptoa(i);
2989 
2990 		/* Contig pages should go back to the cache. */
2991 		m->m_ext.ext_free = ktls_free_mext_contig;
2992 	} else {
2993 		for (i = 0; i < m->m_epg_npgs; i++)
2994 			m->m_epg_pa[i] = state->parray[i];
2995 
2996 		/* Use the basic free routine. */
2997 		m->m_ext.ext_free = mb_free_mext_pgs;
2998 	}
2999 
3000 	/* Pages are now writable. */
3001 	m->m_epg_flags |= EPG_FLAG_ANON;
3002 }
3003 
3004 static __noinline void
ktls_encrypt(struct ktls_wq * wq,struct mbuf * top)3005 ktls_encrypt(struct ktls_wq *wq, struct mbuf *top)
3006 {
3007 	struct ktls_ocf_encrypt_state state;
3008 	struct ktls_session *tls;
3009 	struct socket *so;
3010 	struct mbuf *m;
3011 	int error, npages, total_pages;
3012 
3013 	so = top->m_epg_so;
3014 	tls = top->m_epg_tls;
3015 	KASSERT(tls != NULL, ("tls = NULL, top = %p\n", top));
3016 	KASSERT(so != NULL, ("so = NULL, top = %p\n", top));
3017 #ifdef INVARIANTS
3018 	top->m_epg_so = NULL;
3019 #endif
3020 	total_pages = top->m_epg_enc_cnt;
3021 	npages = 0;
3022 
3023 	/*
3024 	 * Encrypt the TLS records in the chain of mbufs starting with
3025 	 * 'top'.  'total_pages' gives us a total count of pages and is
3026 	 * used to know when we have finished encrypting the TLS
3027 	 * records originally queued with 'top'.
3028 	 *
3029 	 * NB: These mbufs are queued in the socket buffer and
3030 	 * 'm_next' is traversing the mbufs in the socket buffer.  The
3031 	 * socket buffer lock is not held while traversing this chain.
3032 	 * Since the mbufs are all marked M_NOTREADY their 'm_next'
3033 	 * pointers should be stable.  However, the 'm_next' of the
3034 	 * last mbuf encrypted is not necessarily NULL.  It can point
3035 	 * to other mbufs appended while 'top' was on the TLS work
3036 	 * queue.
3037 	 *
3038 	 * Each mbuf holds an entire TLS record.
3039 	 */
3040 	error = 0;
3041 	for (m = top; npages != total_pages; m = m->m_next) {
3042 		KASSERT(m->m_epg_tls == tls,
3043 		    ("different TLS sessions in a single mbuf chain: %p vs %p",
3044 		    tls, m->m_epg_tls));
3045 		KASSERT(npages + m->m_epg_npgs <= total_pages,
3046 		    ("page count mismatch: top %p, total_pages %d, m %p", top,
3047 		    total_pages, m));
3048 
3049 		error = ktls_encrypt_record(wq, m, tls, &state);
3050 		if (error) {
3051 			counter_u64_add(ktls_offload_failed_crypto, 1);
3052 			break;
3053 		}
3054 
3055 		if ((m->m_epg_flags & EPG_FLAG_ANON) == 0)
3056 			ktls_finish_nonanon(m, &state);
3057 		m->m_flags |= M_RDONLY;
3058 
3059 		npages += m->m_epg_nrdy;
3060 
3061 		/*
3062 		 * Drop a reference to the session now that it is no
3063 		 * longer needed.  Existing code depends on encrypted
3064 		 * records having no associated session vs
3065 		 * yet-to-be-encrypted records having an associated
3066 		 * session.
3067 		 */
3068 		m->m_epg_tls = NULL;
3069 		ktls_free(tls);
3070 	}
3071 
3072 	CURVNET_SET(so->so_vnet);
3073 	if (error == 0) {
3074 		(void)so->so_proto->pr_ready(so, top, npages);
3075 	} else {
3076 		ktls_drop(so, EIO);
3077 		mb_free_notready(top, total_pages);
3078 	}
3079 
3080 	sorele(so);
3081 	CURVNET_RESTORE();
3082 }
3083 
3084 void
ktls_encrypt_cb(struct ktls_ocf_encrypt_state * state,int error)3085 ktls_encrypt_cb(struct ktls_ocf_encrypt_state *state, int error)
3086 {
3087 	struct ktls_session *tls;
3088 	struct socket *so;
3089 	struct mbuf *m;
3090 	int npages;
3091 
3092 	m = state->m;
3093 
3094 	if ((m->m_epg_flags & EPG_FLAG_ANON) == 0)
3095 		ktls_finish_nonanon(m, state);
3096 	m->m_flags |= M_RDONLY;
3097 
3098 	so = state->so;
3099 	free(state, M_KTLS);
3100 
3101 	/*
3102 	 * Drop a reference to the session now that it is no longer
3103 	 * needed.  Existing code depends on encrypted records having
3104 	 * no associated session vs yet-to-be-encrypted records having
3105 	 * an associated session.
3106 	 */
3107 	tls = m->m_epg_tls;
3108 	m->m_epg_tls = NULL;
3109 	ktls_free(tls);
3110 
3111 	if (error != 0)
3112 		counter_u64_add(ktls_offload_failed_crypto, 1);
3113 
3114 	CURVNET_SET(so->so_vnet);
3115 	npages = m->m_epg_nrdy;
3116 
3117 	if (error == 0) {
3118 		(void)so->so_proto->pr_ready(so, m, npages);
3119 	} else {
3120 		ktls_drop(so, EIO);
3121 		mb_free_notready(m, npages);
3122 	}
3123 
3124 	sorele(so);
3125 	CURVNET_RESTORE();
3126 }
3127 
3128 /*
3129  * Similar to ktls_encrypt, but used with asynchronous OCF backends
3130  * (coprocessors) where encryption does not use host CPU resources and
3131  * it can be beneficial to queue more requests than CPUs.
3132  */
3133 static __noinline void
ktls_encrypt_async(struct ktls_wq * wq,struct mbuf * top)3134 ktls_encrypt_async(struct ktls_wq *wq, struct mbuf *top)
3135 {
3136 	struct ktls_ocf_encrypt_state *state;
3137 	struct ktls_session *tls;
3138 	struct socket *so;
3139 	struct mbuf *m, *n;
3140 	int error, mpages, npages, total_pages;
3141 
3142 	so = top->m_epg_so;
3143 	tls = top->m_epg_tls;
3144 	KASSERT(tls != NULL, ("tls = NULL, top = %p\n", top));
3145 	KASSERT(so != NULL, ("so = NULL, top = %p\n", top));
3146 #ifdef INVARIANTS
3147 	top->m_epg_so = NULL;
3148 #endif
3149 	total_pages = top->m_epg_enc_cnt;
3150 	npages = 0;
3151 
3152 	error = 0;
3153 	for (m = top; npages != total_pages; m = n) {
3154 		KASSERT(m->m_epg_tls == tls,
3155 		    ("different TLS sessions in a single mbuf chain: %p vs %p",
3156 		    tls, m->m_epg_tls));
3157 		KASSERT(npages + m->m_epg_npgs <= total_pages,
3158 		    ("page count mismatch: top %p, total_pages %d, m %p", top,
3159 		    total_pages, m));
3160 
3161 		state = malloc(sizeof(*state), M_KTLS, M_WAITOK | M_ZERO);
3162 		soref(so);
3163 		state->so = so;
3164 		state->m = m;
3165 
3166 		mpages = m->m_epg_nrdy;
3167 		n = m->m_next;
3168 
3169 		error = ktls_encrypt_record(wq, m, tls, state);
3170 		if (error) {
3171 			counter_u64_add(ktls_offload_failed_crypto, 1);
3172 			free(state, M_KTLS);
3173 			CURVNET_SET(so->so_vnet);
3174 			sorele(so);
3175 			CURVNET_RESTORE();
3176 			break;
3177 		}
3178 
3179 		npages += mpages;
3180 	}
3181 
3182 	CURVNET_SET(so->so_vnet);
3183 	if (error != 0) {
3184 		ktls_drop(so, EIO);
3185 		mb_free_notready(m, total_pages - npages);
3186 	}
3187 
3188 	sorele(so);
3189 	CURVNET_RESTORE();
3190 }
3191 
3192 static int
ktls_bind_domain(int domain)3193 ktls_bind_domain(int domain)
3194 {
3195 	int error;
3196 
3197 	error = cpuset_setthread(curthread->td_tid, &cpuset_domain[domain]);
3198 	if (error != 0)
3199 		return (error);
3200 	curthread->td_domain.dr_policy = DOMAINSET_PREF(domain);
3201 	return (0);
3202 }
3203 
3204 static void
ktls_reclaim_thread(void * ctx)3205 ktls_reclaim_thread(void *ctx)
3206 {
3207 	struct ktls_domain_info *ktls_domain = ctx;
3208 	struct ktls_reclaim_thread *sc = &ktls_domain->reclaim_td;
3209 	struct sysctl_oid *oid;
3210 	char name[80];
3211 	int error, domain;
3212 
3213 	domain = ktls_domain - ktls_domains;
3214 	if (bootverbose)
3215 		printf("Starting KTLS reclaim thread for domain %d\n", domain);
3216 	error = ktls_bind_domain(domain);
3217 	if (error)
3218 		printf("Unable to bind KTLS reclaim thread for domain %d: error %d\n",
3219 		    domain, error);
3220 	snprintf(name, sizeof(name), "domain%d", domain);
3221 	oid = SYSCTL_ADD_NODE(NULL, SYSCTL_STATIC_CHILDREN(_kern_ipc_tls), OID_AUTO,
3222 	    name, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "");
3223 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "reclaims",
3224 	    CTLFLAG_RD,  &sc->reclaims, 0, "buffers reclaimed");
3225 	SYSCTL_ADD_U64(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "wakeups",
3226 	    CTLFLAG_RD,  &sc->wakeups, 0, "thread wakeups");
3227 	SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(oid), OID_AUTO, "running",
3228 	    CTLFLAG_RD,  &sc->running, 0, "thread running");
3229 
3230 	for (;;) {
3231 		atomic_store_int(&sc->running, 0);
3232 		tsleep(sc, PZERO | PNOLOCK, "-",  0);
3233 		atomic_store_int(&sc->running, 1);
3234 		sc->wakeups++;
3235 		/*
3236 		 * Below we attempt to reclaim ktls_max_reclaim
3237 		 * buffers using vm_page_reclaim_contig_domain_ext().
3238 		 * We do this here, as this function can take several
3239 		 * seconds to scan all of memory and it does not
3240 		 * matter if this thread pauses for a while.  If we
3241 		 * block a ktls worker thread, we risk developing
3242 		 * backlogs of buffers to be encrypted, leading to
3243 		 * surges of traffic and potential NIC output drops.
3244 		 */
3245 		if (vm_page_reclaim_contig_domain_ext(domain, VM_ALLOC_NORMAL,
3246 		    atop(ktls_maxlen), 0, ~0ul, PAGE_SIZE, 0,
3247 		    ktls_max_reclaim) != 0) {
3248 			vm_wait_domain(domain);
3249 		} else {
3250 			sc->reclaims += ktls_max_reclaim;
3251 		}
3252 	}
3253 }
3254 
3255 static void
ktls_work_thread(void * ctx)3256 ktls_work_thread(void *ctx)
3257 {
3258 	struct ktls_wq *wq = ctx;
3259 	struct mbuf *m, *n;
3260 	struct socket *so, *son;
3261 	STAILQ_HEAD(, mbuf) local_m_head;
3262 	STAILQ_HEAD(, socket) local_so_head;
3263 	int cpu;
3264 
3265 	cpu = wq - ktls_wq;
3266 	if (bootverbose)
3267 		printf("Starting KTLS worker thread for CPU %d\n", cpu);
3268 
3269 	/*
3270 	 * Bind to a core.  If ktls_bind_threads is > 1, then
3271 	 * we bind to the NUMA domain instead.
3272 	 */
3273 	if (ktls_bind_threads) {
3274 		int error;
3275 
3276 		if (ktls_bind_threads > 1) {
3277 			struct pcpu *pc = pcpu_find(cpu);
3278 
3279 			error = ktls_bind_domain(pc->pc_domain);
3280 		} else {
3281 			cpuset_t mask;
3282 
3283 			CPU_SETOF(cpu, &mask);
3284 			error = cpuset_setthread(curthread->td_tid, &mask);
3285 		}
3286 		if (error)
3287 			printf("Unable to bind KTLS worker thread for CPU %d: error %d\n",
3288 				cpu, error);
3289 	}
3290 #if defined(__aarch64__) || defined(__amd64__) || defined(__i386__)
3291 	fpu_kern_thread(0);
3292 #endif
3293 	for (;;) {
3294 		mtx_lock(&wq->mtx);
3295 		while (STAILQ_EMPTY(&wq->m_head) &&
3296 		    STAILQ_EMPTY(&wq->so_head)) {
3297 			wq->running = false;
3298 			mtx_sleep(wq, &wq->mtx, 0, "-", 0);
3299 			wq->running = true;
3300 		}
3301 
3302 		STAILQ_INIT(&local_m_head);
3303 		STAILQ_CONCAT(&local_m_head, &wq->m_head);
3304 		STAILQ_INIT(&local_so_head);
3305 		STAILQ_CONCAT(&local_so_head, &wq->so_head);
3306 		mtx_unlock(&wq->mtx);
3307 
3308 		STAILQ_FOREACH_SAFE(m, &local_m_head, m_epg_stailq, n) {
3309 			if (m->m_epg_flags & EPG_FLAG_2FREE) {
3310 				ktls_free(m->m_epg_tls);
3311 				m_free_raw(m);
3312 			} else {
3313 				if (m->m_epg_tls->sync_dispatch)
3314 					ktls_encrypt(wq, m);
3315 				else
3316 					ktls_encrypt_async(wq, m);
3317 				counter_u64_add(ktls_cnt_tx_queued, -1);
3318 			}
3319 		}
3320 
3321 		STAILQ_FOREACH_SAFE(so, &local_so_head, so_ktls_rx_list, son) {
3322 			ktls_decrypt(so);
3323 			counter_u64_add(ktls_cnt_rx_queued, -1);
3324 		}
3325 	}
3326 }
3327 
3328 static void
ktls_disable_ifnet_help(void * context,int pending __unused)3329 ktls_disable_ifnet_help(void *context, int pending __unused)
3330 {
3331 	struct ktls_session *tls;
3332 	struct inpcb *inp;
3333 	struct tcpcb *tp;
3334 	struct socket *so;
3335 	int err;
3336 
3337 	tls = context;
3338 	inp = tls->inp;
3339 	if (inp == NULL)
3340 		return;
3341 	INP_WLOCK(inp);
3342 	so = inp->inp_socket;
3343 	MPASS(so != NULL);
3344 	tp = intotcpcb(inp);
3345 	if (tp->t_flags & TF_DISCONNECTED) {
3346 		goto out;
3347 	}
3348 
3349 	if (so->so_snd.sb_tls_info != NULL)
3350 		err = ktls_set_tx_mode(so, TCP_TLS_MODE_SW);
3351 	else
3352 		err = ENXIO;
3353 	if (err == 0) {
3354 		counter_u64_add(ktls_ifnet_disable_ok, 1);
3355 		/* ktls_set_tx_mode() drops inp wlock, so recheck flags */
3356 		if ((tp->t_flags & TF_DISCONNECTED) == 0 &&
3357 		    tp->t_fb->tfb_hwtls_change != NULL)
3358 			(*tp->t_fb->tfb_hwtls_change)(tp, 0);
3359 	} else {
3360 		counter_u64_add(ktls_ifnet_disable_fail, 1);
3361 	}
3362 
3363 out:
3364 	CURVNET_SET(so->so_vnet);
3365 	sorele(so);
3366 	CURVNET_RESTORE();
3367 	INP_WUNLOCK(inp);
3368 	ktls_free(tls);
3369 }
3370 
3371 /*
3372  * Called when re-transmits are becoming a substantial portion of the
3373  * sends on this connection.  When this happens, we transition the
3374  * connection to software TLS.  This is needed because most inline TLS
3375  * NICs keep crypto state only for in-order transmits.  This means
3376  * that to handle a TCP rexmit (which is out-of-order), the NIC must
3377  * re-DMA the entire TLS record up to and including the current
3378  * segment.  This means that when re-transmitting the last ~1448 byte
3379  * segment of a 16KB TLS record, we could wind up re-DMA'ing an order
3380  * of magnitude more data than we are sending.  This can cause the
3381  * PCIe link to saturate well before the network, which can cause
3382  * output drops, and a general loss of capacity.
3383  */
3384 void
ktls_disable_ifnet(void * arg)3385 ktls_disable_ifnet(void *arg)
3386 {
3387 	struct tcpcb *tp;
3388 	struct inpcb *inp;
3389 	struct socket *so;
3390 	struct ktls_session *tls;
3391 
3392 	tp = arg;
3393 	inp = tptoinpcb(tp);
3394 	INP_WLOCK_ASSERT(inp);
3395 	so = inp->inp_socket;
3396 	SOCK_LOCK(so);
3397 	tls = so->so_snd.sb_tls_info;
3398 	if (tp->t_nic_ktls_xmit_dis == 1) {
3399 		SOCK_UNLOCK(so);
3400 		return;
3401 	}
3402 
3403 	/*
3404 	 * note that t_nic_ktls_xmit_dis is never cleared; disabling
3405 	 * ifnet can only be done once per connection, so we never want
3406 	 * to do it again
3407 	 */
3408 
3409 	(void)ktls_hold(tls);
3410 	soref(so);
3411 	tp->t_nic_ktls_xmit_dis = 1;
3412 	SOCK_UNLOCK(so);
3413 	TASK_INIT(&tls->disable_ifnet_task, 0, ktls_disable_ifnet_help, tls);
3414 	(void)taskqueue_enqueue(taskqueue_thread, &tls->disable_ifnet_task);
3415 }
3416 
3417 void
ktls_session_to_xktls_onedir(const struct ktls_session * ktls,bool export_keys,struct xktls_session_onedir * xk)3418 ktls_session_to_xktls_onedir(const struct ktls_session *ktls, bool export_keys,
3419     struct xktls_session_onedir *xk)
3420 {
3421 	if_t ifp;
3422 	struct m_snd_tag *st;
3423 
3424 	xk->gen = ktls->gen;
3425 #define	A(m) xk->m = ktls->params.m
3426 	A(cipher_algorithm);
3427 	A(auth_algorithm);
3428 	A(cipher_key_len);
3429 	A(auth_key_len);
3430 	A(max_frame_len);
3431 	A(tls_vmajor);
3432 	A(tls_vminor);
3433 	A(tls_hlen);
3434 	A(tls_tlen);
3435 	A(tls_bs);
3436 	A(flags);
3437 	if (export_keys) {
3438 		memcpy(&xk->iv, &ktls->params.iv, XKTLS_SESSION_IV_BUF_LEN);
3439 		A(iv_len);
3440 	} else {
3441 		memset(&xk->iv, 0, XKTLS_SESSION_IV_BUF_LEN);
3442 		xk->iv_len = 0;
3443 	}
3444 #undef A
3445 	if ((st = ktls->snd_tag) != NULL &&
3446 	    (ifp = ktls->snd_tag->ifp) != NULL)
3447 		strncpy(xk->ifnet, if_name(ifp), sizeof(xk->ifnet));
3448 }
3449 
3450 void
ktls_session_copy_keys(const struct ktls_session * ktls,uint8_t * data,size_t * sz)3451 ktls_session_copy_keys(const struct ktls_session *ktls,
3452     uint8_t *data, size_t *sz)
3453 {
3454 	size_t t, ta, tc;
3455 
3456 	if (ktls == NULL) {
3457 		*sz = 0;
3458 		return;
3459 	}
3460 	t = *sz;
3461 	tc = MIN(t, ktls->params.cipher_key_len);
3462 	if (data != NULL)
3463 		memcpy(data, ktls->params.cipher_key, tc);
3464 	ta = MIN(t - tc, ktls->params.auth_key_len);
3465 	if (data != NULL)
3466 		memcpy(data + tc, ktls->params.auth_key, ta);
3467 	*sz = ta + tc;
3468 }
3469