xref: /freebsd/sys/opencrypto/ktls_ocf.c (revision e17f5b1d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2019 Netflix Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/counter.h>
35 #include <sys/endian.h>
36 #include <sys/kernel.h>
37 #include <sys/ktls.h>
38 #include <sys/lock.h>
39 #include <sys/malloc.h>
40 #include <sys/module.h>
41 #include <sys/mutex.h>
42 #include <sys/sysctl.h>
43 #include <sys/uio.h>
44 #include <opencrypto/cryptodev.h>
45 
46 struct ocf_session {
47 	crypto_session_t sid;
48 	struct mtx lock;
49 };
50 
51 struct ocf_operation {
52 	struct ocf_session *os;
53 	bool done;
54 	struct iovec iov[0];
55 };
56 
57 static MALLOC_DEFINE(M_KTLS_OCF, "ktls_ocf", "OCF KTLS");
58 
59 SYSCTL_DECL(_kern_ipc_tls);
60 SYSCTL_DECL(_kern_ipc_tls_stats);
61 
62 static SYSCTL_NODE(_kern_ipc_tls_stats, OID_AUTO, ocf,
63     CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
64     "Kernel TLS offload via OCF stats");
65 
66 static counter_u64_t ocf_tls12_gcm_crypts;
67 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls12_gcm_crypts,
68     CTLFLAG_RD, &ocf_tls12_gcm_crypts,
69     "Total number of OCF TLS 1.2 GCM encryption operations");
70 
71 static counter_u64_t ocf_tls13_gcm_crypts;
72 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, tls13_gcm_crypts,
73     CTLFLAG_RD, &ocf_tls13_gcm_crypts,
74     "Total number of OCF TLS 1.3 GCM encryption operations");
75 
76 static counter_u64_t ocf_inplace;
77 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, inplace,
78     CTLFLAG_RD, &ocf_inplace,
79     "Total number of OCF in-place operations");
80 
81 static counter_u64_t ocf_separate_output;
82 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, separate_output,
83     CTLFLAG_RD, &ocf_separate_output,
84     "Total number of OCF operations with a separate output buffer");
85 
86 static counter_u64_t ocf_retries;
87 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, retries, CTLFLAG_RD,
88     &ocf_retries,
89     "Number of OCF encryption operation retries");
90 
91 static int
92 ktls_ocf_callback(struct cryptop *crp)
93 {
94 	struct ocf_operation *oo;
95 
96 	oo = crp->crp_opaque;
97 	mtx_lock(&oo->os->lock);
98 	oo->done = true;
99 	mtx_unlock(&oo->os->lock);
100 	wakeup(oo);
101 	return (0);
102 }
103 
104 static int
105 ktls_ocf_tls12_gcm_encrypt(struct ktls_session *tls,
106     const struct tls_record_layer *hdr, uint8_t *trailer, struct iovec *iniov,
107     struct iovec *outiov, int iovcnt, uint64_t seqno,
108     uint8_t record_type __unused)
109 {
110 	struct uio uio, out_uio, *tag_uio;
111 	struct tls_aead_data ad;
112 	struct cryptop *crp;
113 	struct ocf_session *os;
114 	struct ocf_operation *oo;
115 	int i, error;
116 	uint16_t tls_comp_len;
117 	bool inplace;
118 
119 	os = tls->cipher;
120 
121 	oo = malloc(sizeof(*oo) + (iovcnt + 1) * sizeof(struct iovec),
122 	    M_KTLS_OCF, M_WAITOK | M_ZERO);
123 	oo->os = os;
124 
125 	uio.uio_iov = iniov;
126 	uio.uio_iovcnt = iovcnt;
127 	uio.uio_offset = 0;
128 	uio.uio_segflg = UIO_SYSSPACE;
129 	uio.uio_td = curthread;
130 
131 	out_uio.uio_iov = outiov;
132 	out_uio.uio_iovcnt = iovcnt;
133 	out_uio.uio_offset = 0;
134 	out_uio.uio_segflg = UIO_SYSSPACE;
135 	out_uio.uio_td = curthread;
136 
137 	crp = crypto_getreq(os->sid, M_WAITOK);
138 
139 	/* Setup the IV. */
140 	memcpy(crp->crp_iv, tls->params.iv, TLS_AEAD_GCM_LEN);
141 	memcpy(crp->crp_iv + TLS_AEAD_GCM_LEN, hdr + 1, sizeof(uint64_t));
142 
143 	/* Setup the AAD. */
144 	tls_comp_len = ntohs(hdr->tls_length) -
145 	    (AES_GMAC_HASH_LEN + sizeof(uint64_t));
146 	ad.seq = htobe64(seqno);
147 	ad.type = hdr->tls_type;
148 	ad.tls_vmajor = hdr->tls_vmajor;
149 	ad.tls_vminor = hdr->tls_vminor;
150 	ad.tls_length = htons(tls_comp_len);
151 	crp->crp_aad = &ad;
152 	crp->crp_aad_length = sizeof(ad);
153 
154 	/* Compute payload length and determine if encryption is in place. */
155 	inplace = true;
156 	crp->crp_payload_start = 0;
157 	for (i = 0; i < iovcnt; i++) {
158 		if (iniov[i].iov_base != outiov[i].iov_base)
159 			inplace = false;
160 		crp->crp_payload_length += iniov[i].iov_len;
161 	}
162 	uio.uio_resid = crp->crp_payload_length;
163 	out_uio.uio_resid = crp->crp_payload_length;
164 
165 	if (inplace)
166 		tag_uio = &uio;
167 	else
168 		tag_uio = &out_uio;
169 
170 	/* Duplicate iovec and append vector for tag. */
171 	memcpy(oo->iov, tag_uio->uio_iov, iovcnt * sizeof(struct iovec));
172 	tag_uio->uio_iov = oo->iov;
173 	tag_uio->uio_iov[iovcnt].iov_base = trailer;
174 	tag_uio->uio_iov[iovcnt].iov_len = AES_GMAC_HASH_LEN;
175 	tag_uio->uio_iovcnt++;
176 	crp->crp_digest_start = tag_uio->uio_resid;
177 	tag_uio->uio_resid += AES_GMAC_HASH_LEN;
178 
179 	crp->crp_op = CRYPTO_OP_ENCRYPT | CRYPTO_OP_COMPUTE_DIGEST;
180 	crp->crp_flags = CRYPTO_F_CBIMM | CRYPTO_F_IV_SEPARATE;
181 	crypto_use_uio(crp, &uio);
182 	if (!inplace)
183 		crypto_use_output_uio(crp, &out_uio);
184 	crp->crp_opaque = oo;
185 	crp->crp_callback = ktls_ocf_callback;
186 
187 	counter_u64_add(ocf_tls12_gcm_crypts, 1);
188 	if (inplace)
189 		counter_u64_add(ocf_inplace, 1);
190 	else
191 		counter_u64_add(ocf_separate_output, 1);
192 	for (;;) {
193 		error = crypto_dispatch(crp);
194 		if (error)
195 			break;
196 
197 		mtx_lock(&os->lock);
198 		while (!oo->done)
199 			mtx_sleep(oo, &os->lock, 0, "ocfktls", 0);
200 		mtx_unlock(&os->lock);
201 
202 		if (crp->crp_etype != EAGAIN) {
203 			error = crp->crp_etype;
204 			break;
205 		}
206 
207 		crp->crp_etype = 0;
208 		crp->crp_flags &= ~CRYPTO_F_DONE;
209 		oo->done = false;
210 		counter_u64_add(ocf_retries, 1);
211 	}
212 
213 	crypto_freereq(crp);
214 	free(oo, M_KTLS_OCF);
215 	return (error);
216 }
217 
218 static int
219 ktls_ocf_tls13_gcm_encrypt(struct ktls_session *tls,
220     const struct tls_record_layer *hdr, uint8_t *trailer, struct iovec *iniov,
221     struct iovec *outiov, int iovcnt, uint64_t seqno, uint8_t record_type)
222 {
223 	struct uio uio, out_uio;
224 	struct tls_aead_data_13 ad;
225 	char nonce[12];
226 	struct cryptop *crp;
227 	struct ocf_session *os;
228 	struct ocf_operation *oo;
229 	struct iovec *iov, *out_iov;
230 	int i, error;
231 	bool inplace;
232 
233 	os = tls->cipher;
234 
235 	oo = malloc(sizeof(*oo) + (iovcnt + 1) * sizeof(*iov) * 2, M_KTLS_OCF,
236 	    M_WAITOK | M_ZERO);
237 	oo->os = os;
238 	iov = oo->iov;
239 	out_iov = iov + iovcnt + 2;
240 
241 	crp = crypto_getreq(os->sid, M_WAITOK);
242 
243 	/* Setup the nonce. */
244 	memcpy(nonce, tls->params.iv, tls->params.iv_len);
245 	*(uint64_t *)(nonce + 4) ^= htobe64(seqno);
246 
247 	/* Setup the AAD. */
248 	ad.type = hdr->tls_type;
249 	ad.tls_vmajor = hdr->tls_vmajor;
250 	ad.tls_vminor = hdr->tls_vminor;
251 	ad.tls_length = hdr->tls_length;
252 	crp->crp_aad = &ad;
253 	crp->crp_aad_length = sizeof(ad);
254 
255 	/* Compute payload length and determine if encryption is in place. */
256 	inplace = true;
257 	crp->crp_payload_start = 0;
258 	for (i = 0; i < iovcnt; i++) {
259 		if (iniov[i].iov_base != outiov[i].iov_base)
260 			inplace = false;
261 		crp->crp_payload_length += iniov[i].iov_len;
262 	}
263 
264 	/* Store the record type as the first byte of the trailer. */
265 	trailer[0] = record_type;
266 	crp->crp_payload_length++;
267 	crp->crp_digest_start = crp->crp_payload_length;
268 
269 	/*
270 	 * Duplicate the input iov to append the trailer.  Always
271 	 * include the full trailer as input to get the record_type
272 	 * even if only the first byte is used.
273 	 */
274 	memcpy(iov, iniov, iovcnt * sizeof(*iov));
275 	iov[iovcnt].iov_base = trailer;
276 	iov[iovcnt].iov_len = AES_GMAC_HASH_LEN + 1;
277 	uio.uio_iov = iov;
278 	uio.uio_iovcnt = iovcnt + 1;
279 	uio.uio_offset = 0;
280 	uio.uio_resid = crp->crp_payload_length + AES_GMAC_HASH_LEN;
281 	uio.uio_segflg = UIO_SYSSPACE;
282 	uio.uio_td = curthread;
283 	crypto_use_uio(crp, &uio);
284 
285 	if (!inplace) {
286 		/* Duplicate the output iov to append the trailer. */
287 		memcpy(out_iov, outiov, iovcnt * sizeof(*out_iov));
288 		out_iov[iovcnt] = iov[iovcnt];
289 
290 		out_uio.uio_iov = out_iov;
291 		out_uio.uio_iovcnt = iovcnt + 1;
292 		out_uio.uio_offset = 0;
293 		out_uio.uio_resid = crp->crp_payload_length +
294 		    AES_GMAC_HASH_LEN;
295 		out_uio.uio_segflg = UIO_SYSSPACE;
296 		out_uio.uio_td = curthread;
297 		crypto_use_output_uio(crp, &out_uio);
298 	}
299 
300 	crp->crp_op = CRYPTO_OP_ENCRYPT | CRYPTO_OP_COMPUTE_DIGEST;
301 	crp->crp_flags = CRYPTO_F_CBIMM | CRYPTO_F_IV_SEPARATE;
302 	crp->crp_opaque = oo;
303 	crp->crp_callback = ktls_ocf_callback;
304 
305 	memcpy(crp->crp_iv, nonce, sizeof(nonce));
306 
307 	counter_u64_add(ocf_tls13_gcm_crypts, 1);
308 	if (inplace)
309 		counter_u64_add(ocf_inplace, 1);
310 	else
311 		counter_u64_add(ocf_separate_output, 1);
312 	for (;;) {
313 		error = crypto_dispatch(crp);
314 		if (error)
315 			break;
316 
317 		mtx_lock(&os->lock);
318 		while (!oo->done)
319 			mtx_sleep(oo, &os->lock, 0, "ocfktls", 0);
320 		mtx_unlock(&os->lock);
321 
322 		if (crp->crp_etype != EAGAIN) {
323 			error = crp->crp_etype;
324 			break;
325 		}
326 
327 		crp->crp_etype = 0;
328 		crp->crp_flags &= ~CRYPTO_F_DONE;
329 		oo->done = false;
330 		counter_u64_add(ocf_retries, 1);
331 	}
332 
333 	crypto_freereq(crp);
334 	free(oo, M_KTLS_OCF);
335 	return (error);
336 }
337 
338 static void
339 ktls_ocf_free(struct ktls_session *tls)
340 {
341 	struct ocf_session *os;
342 
343 	os = tls->cipher;
344 	crypto_freesession(os->sid);
345 	mtx_destroy(&os->lock);
346 	zfree(os, M_KTLS_OCF);
347 }
348 
349 static int
350 ktls_ocf_try(struct socket *so, struct ktls_session *tls)
351 {
352 	struct crypto_session_params csp;
353 	struct ocf_session *os;
354 	int error;
355 
356 	memset(&csp, 0, sizeof(csp));
357 	csp.csp_flags |= CSP_F_SEPARATE_OUTPUT | CSP_F_SEPARATE_AAD;
358 
359 	switch (tls->params.cipher_algorithm) {
360 	case CRYPTO_AES_NIST_GCM_16:
361 		switch (tls->params.cipher_key_len) {
362 		case 128 / 8:
363 		case 256 / 8:
364 			break;
365 		default:
366 			return (EINVAL);
367 		}
368 		csp.csp_mode = CSP_MODE_AEAD;
369 		csp.csp_cipher_alg = CRYPTO_AES_NIST_GCM_16;
370 		csp.csp_cipher_key = tls->params.cipher_key;
371 		csp.csp_cipher_klen = tls->params.cipher_key_len;
372 		csp.csp_ivlen = AES_GCM_IV_LEN;
373 		break;
374 	default:
375 		return (EPROTONOSUPPORT);
376 	}
377 
378 	/* Only TLS 1.2 and 1.3 are supported. */
379 	if (tls->params.tls_vmajor != TLS_MAJOR_VER_ONE ||
380 	    tls->params.tls_vminor < TLS_MINOR_VER_TWO ||
381 	    tls->params.tls_vminor > TLS_MINOR_VER_THREE)
382 		return (EPROTONOSUPPORT);
383 
384 	os = malloc(sizeof(*os), M_KTLS_OCF, M_NOWAIT | M_ZERO);
385 	if (os == NULL)
386 		return (ENOMEM);
387 
388 	error = crypto_newsession(&os->sid, &csp,
389 	    CRYPTO_FLAG_HARDWARE | CRYPTO_FLAG_SOFTWARE);
390 	if (error) {
391 		free(os, M_KTLS_OCF);
392 		return (error);
393 	}
394 
395 	mtx_init(&os->lock, "ktls_ocf", NULL, MTX_DEF);
396 	tls->cipher = os;
397 	if (tls->params.tls_vminor == TLS_MINOR_VER_THREE)
398 		tls->sw_encrypt = ktls_ocf_tls13_gcm_encrypt;
399 	else
400 		tls->sw_encrypt = ktls_ocf_tls12_gcm_encrypt;
401 	tls->free = ktls_ocf_free;
402 	return (0);
403 }
404 
405 struct ktls_crypto_backend ocf_backend = {
406 	.name = "OCF",
407 	.prio = 5,
408 	.api_version = KTLS_API_VERSION,
409 	.try = ktls_ocf_try,
410 };
411 
412 static int
413 ktls_ocf_modevent(module_t mod, int what, void *arg)
414 {
415 	int error;
416 
417 	switch (what) {
418 	case MOD_LOAD:
419 		ocf_tls12_gcm_crypts = counter_u64_alloc(M_WAITOK);
420 		ocf_tls13_gcm_crypts = counter_u64_alloc(M_WAITOK);
421 		ocf_inplace = counter_u64_alloc(M_WAITOK);
422 		ocf_separate_output = counter_u64_alloc(M_WAITOK);
423 		ocf_retries = counter_u64_alloc(M_WAITOK);
424 		return (ktls_crypto_backend_register(&ocf_backend));
425 	case MOD_UNLOAD:
426 		error = ktls_crypto_backend_deregister(&ocf_backend);
427 		if (error)
428 			return (error);
429 		counter_u64_free(ocf_tls12_gcm_crypts);
430 		counter_u64_free(ocf_tls13_gcm_crypts);
431 		counter_u64_free(ocf_inplace);
432 		counter_u64_free(ocf_separate_output);
433 		counter_u64_free(ocf_retries);
434 		return (0);
435 	default:
436 		return (EOPNOTSUPP);
437 	}
438 }
439 
440 static moduledata_t ktls_ocf_moduledata = {
441 	"ktls_ocf",
442 	ktls_ocf_modevent,
443 	NULL
444 };
445 
446 DECLARE_MODULE(ktls_ocf, ktls_ocf_moduledata, SI_SUB_PROTO_END, SI_ORDER_ANY);
447