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