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