xref: /freebsd/sys/opencrypto/ktls_ocf.c (revision d65cd7a57bf0600b722afc770838a5d0c1c3a8e1)
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_retries;
77 SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, retries, CTLFLAG_RD,
78     &ocf_retries,
79     "Number of OCF encryption operation retries");
80 
81 static int
82 ktls_ocf_callback(struct cryptop *crp)
83 {
84 	struct ocf_operation *oo;
85 
86 	oo = crp->crp_opaque;
87 	mtx_lock(&oo->os->lock);
88 	oo->done = true;
89 	mtx_unlock(&oo->os->lock);
90 	wakeup(oo);
91 	return (0);
92 }
93 
94 static int
95 ktls_ocf_tls12_gcm_encrypt(struct ktls_session *tls,
96     const struct tls_record_layer *hdr, uint8_t *trailer, struct iovec *iniov,
97     struct iovec *outiov, int iovcnt, uint64_t seqno,
98     uint8_t record_type __unused)
99 {
100 	struct uio uio;
101 	struct tls_aead_data ad;
102 	struct cryptop *crp;
103 	struct ocf_session *os;
104 	struct ocf_operation *oo;
105 	struct iovec *iov;
106 	int i, error;
107 	uint16_t tls_comp_len;
108 
109 	os = tls->cipher;
110 
111 	oo = malloc(sizeof(*oo) + (iovcnt + 2) * sizeof(*iov), M_KTLS_OCF,
112 	    M_WAITOK | M_ZERO);
113 	oo->os = os;
114 	iov = oo->iov;
115 
116 	crp = crypto_getreq(os->sid, M_WAITOK);
117 
118 	/* Setup the IV. */
119 	memcpy(crp->crp_iv, tls->params.iv, TLS_AEAD_GCM_LEN);
120 	memcpy(crp->crp_iv + TLS_AEAD_GCM_LEN, hdr + 1, sizeof(uint64_t));
121 
122 	/* Setup the AAD. */
123 	tls_comp_len = ntohs(hdr->tls_length) -
124 	    (AES_GMAC_HASH_LEN + sizeof(uint64_t));
125 	ad.seq = htobe64(seqno);
126 	ad.type = hdr->tls_type;
127 	ad.tls_vmajor = hdr->tls_vmajor;
128 	ad.tls_vminor = hdr->tls_vminor;
129 	ad.tls_length = htons(tls_comp_len);
130 	iov[0].iov_base = &ad;
131 	iov[0].iov_len = sizeof(ad);
132 	uio.uio_resid = sizeof(ad);
133 
134 	/*
135 	 * OCF always does encryption in place, so copy the data if
136 	 * needed.  Ugh.
137 	 */
138 	for (i = 0; i < iovcnt; i++) {
139 		iov[i + 1] = outiov[i];
140 		if (iniov[i].iov_base != outiov[i].iov_base)
141 			memcpy(outiov[i].iov_base, iniov[i].iov_base,
142 			    outiov[i].iov_len);
143 		uio.uio_resid += outiov[i].iov_len;
144 	}
145 
146 	iov[iovcnt + 1].iov_base = trailer;
147 	iov[iovcnt + 1].iov_len = AES_GMAC_HASH_LEN;
148 	uio.uio_resid += AES_GMAC_HASH_LEN;
149 
150 	uio.uio_iov = iov;
151 	uio.uio_iovcnt = iovcnt + 2;
152 	uio.uio_offset = 0;
153 	uio.uio_segflg = UIO_SYSSPACE;
154 	uio.uio_td = curthread;
155 
156 	crp->crp_op = CRYPTO_OP_ENCRYPT | CRYPTO_OP_COMPUTE_DIGEST;
157 	crp->crp_flags = CRYPTO_F_CBIMM | CRYPTO_F_IV_SEPARATE;
158 	crp->crp_buf_type = CRYPTO_BUF_UIO;
159 	crp->crp_uio = &uio;
160 	crp->crp_ilen = uio.uio_resid;
161 	crp->crp_opaque = oo;
162 	crp->crp_callback = ktls_ocf_callback;
163 
164 	crp->crp_aad_start = 0;
165 	crp->crp_aad_length = sizeof(ad);
166 	crp->crp_payload_start = sizeof(ad);
167 	crp->crp_payload_length = crp->crp_ilen -
168 	    (sizeof(ad) + AES_GMAC_HASH_LEN);
169 	crp->crp_digest_start = crp->crp_ilen - AES_GMAC_HASH_LEN;
170 
171 	counter_u64_add(ocf_tls12_gcm_crypts, 1);
172 	for (;;) {
173 		error = crypto_dispatch(crp);
174 		if (error)
175 			break;
176 
177 		mtx_lock(&os->lock);
178 		while (!oo->done)
179 			mtx_sleep(oo, &os->lock, 0, "ocfktls", 0);
180 		mtx_unlock(&os->lock);
181 
182 		if (crp->crp_etype != EAGAIN) {
183 			error = crp->crp_etype;
184 			break;
185 		}
186 
187 		crp->crp_etype = 0;
188 		crp->crp_flags &= ~CRYPTO_F_DONE;
189 		oo->done = false;
190 		counter_u64_add(ocf_retries, 1);
191 	}
192 
193 	crypto_freereq(crp);
194 	free(oo, M_KTLS_OCF);
195 	return (error);
196 }
197 
198 static int
199 ktls_ocf_tls13_gcm_encrypt(struct ktls_session *tls,
200     const struct tls_record_layer *hdr, uint8_t *trailer, struct iovec *iniov,
201     struct iovec *outiov, int iovcnt, uint64_t seqno, uint8_t record_type)
202 {
203 	struct uio uio;
204 	struct tls_aead_data_13 ad;
205 	char nonce[12];
206 	struct cryptop *crp;
207 	struct ocf_session *os;
208 	struct ocf_operation *oo;
209 	struct iovec *iov;
210 	int i, error;
211 
212 	os = tls->cipher;
213 
214 	oo = malloc(sizeof(*oo) + (iovcnt + 2) * sizeof(*iov), M_KTLS_OCF,
215 	    M_WAITOK | M_ZERO);
216 	oo->os = os;
217 	iov = oo->iov;
218 
219 	crp = crypto_getreq(os->sid, M_WAITOK);
220 
221 	/* Setup the nonce. */
222 	memcpy(nonce, tls->params.iv, tls->params.iv_len);
223 	*(uint64_t *)(nonce + 4) ^= htobe64(seqno);
224 
225 	/* Setup the AAD. */
226 	ad.type = hdr->tls_type;
227 	ad.tls_vmajor = hdr->tls_vmajor;
228 	ad.tls_vminor = hdr->tls_vminor;
229 	ad.tls_length = hdr->tls_length;
230 	iov[0].iov_base = &ad;
231 	iov[0].iov_len = sizeof(ad);
232 	uio.uio_resid = sizeof(ad);
233 
234 	/*
235 	 * OCF always does encryption in place, so copy the data if
236 	 * needed.  Ugh.
237 	 */
238 	for (i = 0; i < iovcnt; i++) {
239 		iov[i + 1] = outiov[i];
240 		if (iniov[i].iov_base != outiov[i].iov_base)
241 			memcpy(outiov[i].iov_base, iniov[i].iov_base,
242 			    outiov[i].iov_len);
243 		uio.uio_resid += outiov[i].iov_len;
244 	}
245 
246 	trailer[0] = record_type;
247 	iov[iovcnt + 1].iov_base = trailer;
248 	iov[iovcnt + 1].iov_len = AES_GMAC_HASH_LEN + 1;
249 	uio.uio_resid += AES_GMAC_HASH_LEN + 1;
250 
251 	uio.uio_iov = iov;
252 	uio.uio_iovcnt = iovcnt + 2;
253 	uio.uio_offset = 0;
254 	uio.uio_segflg = UIO_SYSSPACE;
255 	uio.uio_td = curthread;
256 
257 	crp->crp_op = CRYPTO_OP_ENCRYPT | CRYPTO_OP_COMPUTE_DIGEST;
258 	crp->crp_flags = CRYPTO_F_CBIMM | CRYPTO_F_IV_SEPARATE;
259 	crp->crp_buf_type = CRYPTO_BUF_UIO;
260 	crp->crp_uio = &uio;
261 	crp->crp_ilen = uio.uio_resid;
262 	crp->crp_opaque = oo;
263 	crp->crp_callback = ktls_ocf_callback;
264 
265 	crp->crp_aad_start = 0;
266 	crp->crp_aad_length = sizeof(ad);
267 	crp->crp_payload_start = sizeof(ad);
268 	crp->crp_payload_length = crp->crp_ilen -
269 	    (sizeof(ad) + AES_GMAC_HASH_LEN);
270 	crp->crp_digest_start = crp->crp_ilen - AES_GMAC_HASH_LEN;
271 	memcpy(crp->crp_iv, nonce, sizeof(nonce));
272 
273 	counter_u64_add(ocf_tls13_gcm_crypts, 1);
274 	for (;;) {
275 		error = crypto_dispatch(crp);
276 		if (error)
277 			break;
278 
279 		mtx_lock(&os->lock);
280 		while (!oo->done)
281 			mtx_sleep(oo, &os->lock, 0, "ocfktls", 0);
282 		mtx_unlock(&os->lock);
283 
284 		if (crp->crp_etype != EAGAIN) {
285 			error = crp->crp_etype;
286 			break;
287 		}
288 
289 		crp->crp_etype = 0;
290 		crp->crp_flags &= ~CRYPTO_F_DONE;
291 		oo->done = false;
292 		counter_u64_add(ocf_retries, 1);
293 	}
294 
295 	crypto_freereq(crp);
296 	free(oo, M_KTLS_OCF);
297 	return (error);
298 }
299 
300 static void
301 ktls_ocf_free(struct ktls_session *tls)
302 {
303 	struct ocf_session *os;
304 
305 	os = tls->cipher;
306 	crypto_freesession(os->sid);
307 	mtx_destroy(&os->lock);
308 	explicit_bzero(os, sizeof(*os));
309 	free(os, M_KTLS_OCF);
310 }
311 
312 static int
313 ktls_ocf_try(struct socket *so, struct ktls_session *tls)
314 {
315 	struct crypto_session_params csp;
316 	struct ocf_session *os;
317 	int error;
318 
319 	memset(&csp, 0, sizeof(csp));
320 
321 	switch (tls->params.cipher_algorithm) {
322 	case CRYPTO_AES_NIST_GCM_16:
323 		switch (tls->params.cipher_key_len) {
324 		case 128 / 8:
325 		case 256 / 8:
326 			break;
327 		default:
328 			return (EINVAL);
329 		}
330 		csp.csp_mode = CSP_MODE_AEAD;
331 		csp.csp_cipher_alg = CRYPTO_AES_NIST_GCM_16;
332 		csp.csp_cipher_key = tls->params.cipher_key;
333 		csp.csp_cipher_klen = tls->params.cipher_key_len;
334 		csp.csp_ivlen = AES_GCM_IV_LEN;
335 		break;
336 	default:
337 		return (EPROTONOSUPPORT);
338 	}
339 
340 	/* Only TLS 1.2 and 1.3 are supported. */
341 	if (tls->params.tls_vmajor != TLS_MAJOR_VER_ONE ||
342 	    tls->params.tls_vminor < TLS_MINOR_VER_TWO ||
343 	    tls->params.tls_vminor > TLS_MINOR_VER_THREE)
344 		return (EPROTONOSUPPORT);
345 
346 	os = malloc(sizeof(*os), M_KTLS_OCF, M_NOWAIT | M_ZERO);
347 	if (os == NULL)
348 		return (ENOMEM);
349 
350 	error = crypto_newsession(&os->sid, &csp,
351 	    CRYPTO_FLAG_HARDWARE | CRYPTO_FLAG_SOFTWARE);
352 	if (error) {
353 		free(os, M_KTLS_OCF);
354 		return (error);
355 	}
356 
357 	mtx_init(&os->lock, "ktls_ocf", NULL, MTX_DEF);
358 	tls->cipher = os;
359 	if (tls->params.tls_vminor == TLS_MINOR_VER_THREE)
360 		tls->sw_encrypt = ktls_ocf_tls13_gcm_encrypt;
361 	else
362 		tls->sw_encrypt = ktls_ocf_tls12_gcm_encrypt;
363 	tls->free = ktls_ocf_free;
364 	return (0);
365 }
366 
367 struct ktls_crypto_backend ocf_backend = {
368 	.name = "OCF",
369 	.prio = 5,
370 	.api_version = KTLS_API_VERSION,
371 	.try = ktls_ocf_try,
372 };
373 
374 static int
375 ktls_ocf_modevent(module_t mod, int what, void *arg)
376 {
377 	int error;
378 
379 	switch (what) {
380 	case MOD_LOAD:
381 		ocf_tls12_gcm_crypts = counter_u64_alloc(M_WAITOK);
382 		ocf_tls13_gcm_crypts = counter_u64_alloc(M_WAITOK);
383 		ocf_retries = counter_u64_alloc(M_WAITOK);
384 		return (ktls_crypto_backend_register(&ocf_backend));
385 	case MOD_UNLOAD:
386 		error = ktls_crypto_backend_deregister(&ocf_backend);
387 		if (error)
388 			return (error);
389 		counter_u64_free(ocf_tls12_gcm_crypts);
390 		counter_u64_free(ocf_tls13_gcm_crypts);
391 		counter_u64_free(ocf_retries);
392 		return (0);
393 	default:
394 		return (EOPNOTSUPP);
395 	}
396 }
397 
398 static moduledata_t ktls_ocf_moduledata = {
399 	"ktls_ocf",
400 	ktls_ocf_modevent,
401 	NULL
402 };
403 
404 DECLARE_MODULE(ktls_ocf, ktls_ocf_moduledata, SI_SUB_PROTO_END, SI_ORDER_ANY);
405