1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2005-2011 Pawel Jakub Dawidek <pawel@dawidek.net>
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 AUTHORS 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 AUTHORS 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 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/linker.h>
34 #include <sys/module.h>
35 #include <sys/lock.h>
36 #include <sys/mutex.h>
37 #include <sys/bio.h>
38 #include <sys/sysctl.h>
39 #include <sys/kthread.h>
40 #include <sys/proc.h>
41 #include <sys/sched.h>
42 #include <sys/smp.h>
43 #include <sys/vnode.h>
44
45 #include <vm/uma.h>
46
47 #include <geom/geom.h>
48 #include <geom/geom_dbg.h>
49 #include <geom/eli/g_eli.h>
50 #include <geom/eli/pkcs5v2.h>
51
52 /*
53 * Code paths:
54 * BIO_READ:
55 * g_eli_start -> g_eli_crypto_read -> g_io_request -> g_eli_read_done -> g_eli_crypto_run -> g_eli_crypto_read_done -> g_io_deliver
56 * BIO_WRITE:
57 * g_eli_start -> g_eli_crypto_run -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
58 */
59
60 /*
61 * Copy data from a (potentially unmapped) bio to a kernelspace buffer.
62 *
63 * The buffer must have at least as much room as bp->bio_length.
64 */
65 static void
g_eli_bio_copyin(struct bio * bp,void * kaddr)66 g_eli_bio_copyin(struct bio *bp, void *kaddr)
67 {
68 struct uio uio;
69 struct iovec iov[1];
70
71 iov[0].iov_base = kaddr;
72 iov[0].iov_len = bp->bio_length;
73 uio.uio_iov = iov;
74 uio.uio_iovcnt = 1;
75 uio.uio_offset = 0;
76 uio.uio_resid = bp->bio_length;
77 uio.uio_segflg = UIO_SYSSPACE;
78 uio.uio_rw = UIO_READ;
79 uiomove_fromphys(bp->bio_ma, bp->bio_ma_offset, bp->bio_length, &uio);
80 }
81
82 /*
83 * The function is called after we read and decrypt data.
84 *
85 * g_eli_start -> g_eli_crypto_read -> g_io_request -> g_eli_read_done -> g_eli_crypto_run -> G_ELI_CRYPTO_READ_DONE -> g_io_deliver
86 */
87 static int
g_eli_crypto_read_done(struct cryptop * crp)88 g_eli_crypto_read_done(struct cryptop *crp)
89 {
90 struct g_eli_softc *sc;
91 struct bio *bp;
92
93 if (crp->crp_etype == EAGAIN) {
94 if (g_eli_crypto_rerun(crp) == 0)
95 return (0);
96 }
97 bp = (struct bio *)crp->crp_opaque;
98 bp->bio_inbed++;
99 if (crp->crp_etype == 0) {
100 G_ELI_DEBUG(3, "Crypto READ request done (%d/%d).",
101 bp->bio_inbed, bp->bio_children);
102 bp->bio_completed += crp->crp_payload_length;
103 } else {
104 G_ELI_DEBUG(1, "Crypto READ request failed (%d/%d) error=%d.",
105 bp->bio_inbed, bp->bio_children, crp->crp_etype);
106 if (bp->bio_error == 0)
107 bp->bio_error = crp->crp_etype;
108 }
109 sc = bp->bio_to->geom->softc;
110 if (sc != NULL && crp->crp_cipher_key != NULL)
111 g_eli_key_drop(sc, __DECONST(void *, crp->crp_cipher_key));
112 crypto_freereq(crp);
113 /*
114 * Do we have all sectors already?
115 */
116 if (bp->bio_inbed < bp->bio_children)
117 return (0);
118
119 if (bp->bio_error != 0) {
120 G_ELI_LOGREQ(0, bp, "Crypto READ request failed (error=%d).",
121 bp->bio_error);
122 bp->bio_completed = 0;
123 }
124 /*
125 * Read is finished, send it up.
126 */
127 g_io_deliver(bp, bp->bio_error);
128 if (sc != NULL)
129 atomic_subtract_int(&sc->sc_inflight, 1);
130 return (0);
131 }
132
133 /*
134 * The function is called after data encryption.
135 *
136 * g_eli_start -> g_eli_crypto_run -> G_ELI_CRYPTO_WRITE_DONE -> g_io_request -> g_eli_write_done -> g_io_deliver
137 */
138 static int
g_eli_crypto_write_done(struct cryptop * crp)139 g_eli_crypto_write_done(struct cryptop *crp)
140 {
141 struct g_eli_softc *sc;
142 struct g_geom *gp;
143 struct g_consumer *cp;
144 struct bio *bp, *cbp;
145
146 if (crp->crp_etype == EAGAIN) {
147 if (g_eli_crypto_rerun(crp) == 0)
148 return (0);
149 }
150 bp = (struct bio *)crp->crp_opaque;
151 bp->bio_inbed++;
152 if (crp->crp_etype == 0) {
153 G_ELI_DEBUG(3, "Crypto WRITE request done (%d/%d).",
154 bp->bio_inbed, bp->bio_children);
155 } else {
156 G_ELI_DEBUG(1, "Crypto WRITE request failed (%d/%d) error=%d.",
157 bp->bio_inbed, bp->bio_children, crp->crp_etype);
158 if (bp->bio_error == 0)
159 bp->bio_error = crp->crp_etype;
160 }
161 gp = bp->bio_to->geom;
162 sc = gp->softc;
163 if (crp->crp_cipher_key != NULL)
164 g_eli_key_drop(sc, __DECONST(void *, crp->crp_cipher_key));
165 crypto_freereq(crp);
166 /*
167 * All sectors are already encrypted?
168 */
169 if (bp->bio_inbed < bp->bio_children)
170 return (0);
171 bp->bio_inbed = 0;
172 bp->bio_children = 1;
173 cbp = bp->bio_driver1;
174 bp->bio_driver1 = NULL;
175 if (bp->bio_error != 0) {
176 G_ELI_LOGREQ(0, bp, "Crypto WRITE request failed (error=%d).",
177 bp->bio_error);
178 g_eli_free_data(bp);
179 g_destroy_bio(cbp);
180 g_io_deliver(bp, bp->bio_error);
181 atomic_subtract_int(&sc->sc_inflight, 1);
182 return (0);
183 }
184 cbp->bio_data = bp->bio_driver2;
185 /*
186 * Clear BIO_UNMAPPED, which was inherited from where we cloned the bio
187 * in g_eli_start, because we manually set bio_data
188 */
189 cbp->bio_flags &= ~BIO_UNMAPPED;
190 cbp->bio_done = g_eli_write_done;
191 cp = LIST_FIRST(&gp->consumer);
192 cbp->bio_to = cp->provider;
193 G_ELI_LOGREQ(2, cbp, "Sending request.");
194 /*
195 * Send encrypted data to the provider.
196 */
197 g_io_request(cbp, cp);
198 return (0);
199 }
200
201 /*
202 * The function is called to read encrypted data.
203 *
204 * g_eli_start -> G_ELI_CRYPTO_READ -> g_io_request -> g_eli_read_done -> g_eli_crypto_run -> g_eli_crypto_read_done -> g_io_deliver
205 */
206 void
g_eli_crypto_read(struct g_eli_softc * sc,struct bio * bp,boolean_t fromworker)207 g_eli_crypto_read(struct g_eli_softc *sc, struct bio *bp, boolean_t fromworker)
208 {
209 struct g_consumer *cp;
210 struct bio *cbp;
211
212 if (!fromworker) {
213 /*
214 * We are not called from the worker thread, so check if
215 * device is suspended.
216 */
217 mtx_lock(&sc->sc_queue_mtx);
218 if (sc->sc_flags & G_ELI_FLAG_SUSPEND) {
219 /*
220 * If device is suspended, we place the request onto
221 * the queue, so it can be handled after resume.
222 */
223 G_ELI_DEBUG(0, "device suspended, move onto queue");
224 bioq_insert_tail(&sc->sc_queue, bp);
225 mtx_unlock(&sc->sc_queue_mtx);
226 wakeup(sc);
227 return;
228 }
229 atomic_add_int(&sc->sc_inflight, 1);
230 mtx_unlock(&sc->sc_queue_mtx);
231 }
232 G_ELI_SETWORKER(bp->bio_pflags, 0);
233 bp->bio_driver2 = NULL;
234 cbp = bp->bio_driver1;
235 cbp->bio_done = g_eli_read_done;
236 cp = LIST_FIRST(&sc->sc_geom->consumer);
237 cbp->bio_to = cp->provider;
238 G_ELI_LOGREQ(2, cbp, "Sending request.");
239 /*
240 * Read encrypted data from provider.
241 */
242 g_io_request(cbp, cp);
243 }
244
245 /*
246 * This is the main function responsible for cryptography (ie. communication
247 * with crypto(9) subsystem).
248 *
249 * BIO_READ:
250 * g_eli_start -> g_eli_crypto_read -> g_io_request -> g_eli_read_done -> G_ELI_CRYPTO_RUN -> g_eli_crypto_read_done -> g_io_deliver
251 * BIO_WRITE:
252 * g_eli_start -> G_ELI_CRYPTO_RUN -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
253 */
254 void
g_eli_crypto_run(struct g_eli_worker * wr,struct bio * bp)255 g_eli_crypto_run(struct g_eli_worker *wr, struct bio *bp)
256 {
257 struct g_eli_softc *sc;
258 struct cryptopq crpq;
259 struct cryptop *crp;
260 vm_page_t *pages;
261 u_int i, nsec, secsize;
262 off_t dstoff;
263 u_char *data = NULL;
264 int error __diagused, pages_offset;
265 bool batch;
266
267 G_ELI_LOGREQ(3, bp, "%s", __func__);
268
269 G_ELI_SETWORKER(bp->bio_pflags, wr->w_number);
270 sc = wr->w_softc;
271 secsize = LIST_FIRST(&sc->sc_geom->provider)->sectorsize;
272 nsec = bp->bio_length / secsize;
273
274 bp->bio_inbed = 0;
275 bp->bio_children = nsec;
276
277 /*
278 * If we write the data we cannot destroy current bio_data content,
279 * so we need to allocate more memory for encrypted data.
280 */
281 if (bp->bio_cmd == BIO_WRITE) {
282 if (!g_eli_alloc_data(bp, bp->bio_length)) {
283 G_ELI_LOGREQ(0, bp, "Crypto request failed (ENOMEM).");
284 if (bp->bio_driver1 != NULL) {
285 g_destroy_bio(bp->bio_driver1);
286 bp->bio_driver1 = NULL;
287 }
288 bp->bio_error = ENOMEM;
289 g_io_deliver(bp, bp->bio_error);
290 if (sc != NULL)
291 atomic_subtract_int(&sc->sc_inflight, 1);
292 return;
293 }
294 data = bp->bio_driver2;
295 /*
296 * This copy could be eliminated by using crypto's output
297 * buffer, instead of using a single overwriting buffer.
298 */
299 if ((bp->bio_flags & BIO_UNMAPPED) != 0)
300 g_eli_bio_copyin(bp, data);
301 else
302 bcopy(bp->bio_data, data, bp->bio_length);
303 } else {
304 if ((bp->bio_flags & BIO_UNMAPPED) != 0) {
305 pages = bp->bio_ma;
306 pages_offset = bp->bio_ma_offset;
307 } else {
308 data = bp->bio_data;
309 }
310 }
311
312 TAILQ_INIT(&crpq);
313 batch = atomic_load_int(&g_eli_batch) != 0;
314
315 for (i = 0, dstoff = bp->bio_offset; i < nsec; i++, dstoff += secsize) {
316 crp = crypto_getreq(wr->w_sid, M_WAITOK);
317
318 if (data) {
319 crypto_use_buf(crp, data, secsize);
320 data += secsize;
321 } else {
322 MPASS(pages != NULL);
323 crypto_use_vmpage(crp, pages, secsize, pages_offset);
324 pages_offset += secsize;
325 pages += pages_offset >> PAGE_SHIFT;
326 pages_offset &= PAGE_MASK;
327 }
328 crp->crp_opaque = (void *)bp;
329 if (bp->bio_cmd == BIO_WRITE) {
330 crp->crp_op = CRYPTO_OP_ENCRYPT;
331 crp->crp_callback = g_eli_crypto_write_done;
332 } else /* if (bp->bio_cmd == BIO_READ) */ {
333 crp->crp_op = CRYPTO_OP_DECRYPT;
334 crp->crp_callback = g_eli_crypto_read_done;
335 }
336 crp->crp_flags = CRYPTO_F_CBIFSYNC;
337 crp->crp_payload_start = 0;
338 crp->crp_payload_length = secsize;
339 if ((sc->sc_flags & G_ELI_FLAG_SINGLE_KEY) == 0) {
340 crp->crp_cipher_key = g_eli_key_hold(sc, dstoff,
341 secsize);
342 }
343 if (g_eli_ivlen(sc->sc_ealgo) != 0) {
344 crp->crp_flags |= CRYPTO_F_IV_SEPARATE;
345 g_eli_crypto_ivgen(sc, dstoff, crp->crp_iv,
346 sizeof(crp->crp_iv));
347 }
348
349 if (batch) {
350 TAILQ_INSERT_TAIL(&crpq, crp, crp_next);
351 } else {
352 error = crypto_dispatch(crp);
353 KASSERT(error == 0,
354 ("crypto_dispatch() failed (error=%d)", error));
355 }
356 }
357
358 if (batch)
359 crypto_dispatch_batch(&crpq, 0);
360 }
361