g_eli_privacy.c revision 339023
1/*-
2 * Copyright (c) 2005-2011 Pawel Jakub Dawidek <pawel@dawidek.net>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: stable/11/sys/geom/eli/g_eli_privacy.c 339023 2018-09-30 12:25:38Z oshogbo $");
29
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/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
60MALLOC_DECLARE(M_ELI);
61
62/*
63 * The function is called after we read and decrypt data.
64 *
65 * 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
66 */
67static int
68g_eli_crypto_read_done(struct cryptop *crp)
69{
70	struct g_eli_softc *sc;
71	struct bio *bp;
72
73	if (crp->crp_etype == EAGAIN) {
74		if (g_eli_crypto_rerun(crp) == 0)
75			return (0);
76	}
77	bp = (struct bio *)crp->crp_opaque;
78	bp->bio_inbed++;
79	if (crp->crp_etype == 0) {
80		G_ELI_DEBUG(3, "Crypto READ request done (%d/%d).",
81		    bp->bio_inbed, bp->bio_children);
82		bp->bio_completed += crp->crp_olen;
83	} else {
84		G_ELI_DEBUG(1, "Crypto READ request failed (%d/%d) error=%d.",
85		    bp->bio_inbed, bp->bio_children, crp->crp_etype);
86		if (bp->bio_error == 0)
87			bp->bio_error = crp->crp_etype;
88	}
89	sc = bp->bio_to->geom->softc;
90	if (sc != NULL)
91		g_eli_key_drop(sc, crp->crp_desc->crd_key);
92	/*
93	 * Do we have all sectors already?
94	 */
95	if (bp->bio_inbed < bp->bio_children)
96		return (0);
97	free(bp->bio_driver2, M_ELI);
98	bp->bio_driver2 = NULL;
99	if (bp->bio_error != 0) {
100		G_ELI_LOGREQ(0, bp, "Crypto READ request failed (error=%d).",
101		    bp->bio_error);
102		bp->bio_completed = 0;
103	}
104	/*
105	 * Read is finished, send it up.
106	 */
107	g_io_deliver(bp, bp->bio_error);
108	if (sc != NULL)
109		atomic_subtract_int(&sc->sc_inflight, 1);
110	return (0);
111}
112
113/*
114 * The function is called after data encryption.
115 *
116 * g_eli_start -> g_eli_crypto_run -> G_ELI_CRYPTO_WRITE_DONE -> g_io_request -> g_eli_write_done -> g_io_deliver
117 */
118static int
119g_eli_crypto_write_done(struct cryptop *crp)
120{
121	struct g_eli_softc *sc;
122	struct g_geom *gp;
123	struct g_consumer *cp;
124	struct bio *bp, *cbp;
125
126	if (crp->crp_etype == EAGAIN) {
127		if (g_eli_crypto_rerun(crp) == 0)
128			return (0);
129	}
130	bp = (struct bio *)crp->crp_opaque;
131	bp->bio_inbed++;
132	if (crp->crp_etype == 0) {
133		G_ELI_DEBUG(3, "Crypto WRITE request done (%d/%d).",
134		    bp->bio_inbed, bp->bio_children);
135	} else {
136		G_ELI_DEBUG(1, "Crypto WRITE request failed (%d/%d) error=%d.",
137		    bp->bio_inbed, bp->bio_children, crp->crp_etype);
138		if (bp->bio_error == 0)
139			bp->bio_error = crp->crp_etype;
140	}
141	gp = bp->bio_to->geom;
142	sc = gp->softc;
143	g_eli_key_drop(sc, crp->crp_desc->crd_key);
144	/*
145	 * All sectors are already encrypted?
146	 */
147	if (bp->bio_inbed < bp->bio_children)
148		return (0);
149	bp->bio_inbed = 0;
150	bp->bio_children = 1;
151	cbp = bp->bio_driver1;
152	bp->bio_driver1 = NULL;
153	if (bp->bio_error != 0) {
154		G_ELI_LOGREQ(0, bp, "Crypto WRITE request failed (error=%d).",
155		    bp->bio_error);
156		free(bp->bio_driver2, M_ELI);
157		bp->bio_driver2 = NULL;
158		g_destroy_bio(cbp);
159		g_io_deliver(bp, bp->bio_error);
160		atomic_subtract_int(&sc->sc_inflight, 1);
161		return (0);
162	}
163	cbp->bio_data = bp->bio_driver2;
164	cbp->bio_done = g_eli_write_done;
165	cp = LIST_FIRST(&gp->consumer);
166	cbp->bio_to = cp->provider;
167	G_ELI_LOGREQ(2, cbp, "Sending request.");
168	/*
169	 * Send encrypted data to the provider.
170	 */
171	g_io_request(cbp, cp);
172	return (0);
173}
174
175/*
176 * The function is called to read encrypted data.
177 *
178 * 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
179 */
180void
181g_eli_crypto_read(struct g_eli_softc *sc, struct bio *bp, boolean_t fromworker)
182{
183	struct g_consumer *cp;
184	struct bio *cbp;
185
186	if (!fromworker) {
187		/*
188		 * We are not called from the worker thread, so check if
189		 * device is suspended.
190		 */
191		mtx_lock(&sc->sc_queue_mtx);
192		if (sc->sc_flags & G_ELI_FLAG_SUSPEND) {
193			/*
194			 * If device is suspended, we place the request onto
195			 * the queue, so it can be handled after resume.
196			 */
197			G_ELI_DEBUG(0, "device suspended, move onto queue");
198			bioq_insert_tail(&sc->sc_queue, bp);
199			mtx_unlock(&sc->sc_queue_mtx);
200			wakeup(sc);
201			return;
202		}
203		atomic_add_int(&sc->sc_inflight, 1);
204		mtx_unlock(&sc->sc_queue_mtx);
205	}
206	bp->bio_pflags = 0;
207	bp->bio_driver2 = NULL;
208	cbp = bp->bio_driver1;
209	cbp->bio_done = g_eli_read_done;
210	cp = LIST_FIRST(&sc->sc_geom->consumer);
211	cbp->bio_to = cp->provider;
212	G_ELI_LOGREQ(2, cbp, "Sending request.");
213	/*
214	 * Read encrypted data from provider.
215	 */
216	g_io_request(cbp, cp);
217}
218
219/*
220 * This is the main function responsible for cryptography (ie. communication
221 * with crypto(9) subsystem).
222 *
223 * BIO_READ:
224 *	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
225 * BIO_WRITE:
226 *	g_eli_start -> G_ELI_CRYPTO_RUN -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver
227 */
228void
229g_eli_crypto_run(struct g_eli_worker *wr, struct bio *bp)
230{
231	struct g_eli_softc *sc;
232	struct cryptop *crp;
233	struct cryptodesc *crd;
234	u_int i, nsec, secsize;
235	off_t dstoff;
236	size_t size;
237	u_char *p, *data;
238	int error;
239
240	G_ELI_LOGREQ(3, bp, "%s", __func__);
241
242	bp->bio_pflags = wr->w_number;
243	sc = wr->w_softc;
244	secsize = LIST_FIRST(&sc->sc_geom->provider)->sectorsize;
245	nsec = bp->bio_length / secsize;
246
247	/*
248	 * Calculate how much memory do we need.
249	 * We need separate crypto operation for every single sector.
250	 * It is much faster to calculate total amount of needed memory here and
251	 * do the allocation once instead of allocating memory in pieces (many,
252	 * many pieces).
253	 */
254	size = sizeof(*crp) * nsec;
255	size += sizeof(*crd) * nsec;
256	/*
257	 * If we write the data we cannot destroy current bio_data content,
258	 * so we need to allocate more memory for encrypted data.
259	 */
260	if (bp->bio_cmd == BIO_WRITE)
261		size += bp->bio_length;
262	p = malloc(size, M_ELI, M_WAITOK);
263
264	bp->bio_inbed = 0;
265	bp->bio_children = nsec;
266	bp->bio_driver2 = p;
267
268	if (bp->bio_cmd == BIO_READ)
269		data = bp->bio_data;
270	else {
271		data = p;
272		p += bp->bio_length;
273		bcopy(bp->bio_data, data, bp->bio_length);
274	}
275
276	for (i = 0, dstoff = bp->bio_offset; i < nsec; i++, dstoff += secsize) {
277		crp = (struct cryptop *)p;	p += sizeof(*crp);
278		crd = (struct cryptodesc *)p;	p += sizeof(*crd);
279
280		crp->crp_sid = wr->w_sid;
281		crp->crp_ilen = secsize;
282		crp->crp_olen = secsize;
283		crp->crp_opaque = (void *)bp;
284		crp->crp_buf = (void *)data;
285		data += secsize;
286		if (bp->bio_cmd == BIO_WRITE)
287			crp->crp_callback = g_eli_crypto_write_done;
288		else /* if (bp->bio_cmd == BIO_READ) */
289			crp->crp_callback = g_eli_crypto_read_done;
290		crp->crp_flags = CRYPTO_F_CBIFSYNC;
291		if (g_eli_batch)
292			crp->crp_flags |= CRYPTO_F_BATCH;
293		crp->crp_desc = crd;
294
295		crd->crd_skip = 0;
296		crd->crd_len = secsize;
297		crd->crd_flags = CRD_F_IV_EXPLICIT | CRD_F_IV_PRESENT;
298		if ((sc->sc_flags & G_ELI_FLAG_SINGLE_KEY) == 0)
299			crd->crd_flags |= CRD_F_KEY_EXPLICIT;
300		if (bp->bio_cmd == BIO_WRITE)
301			crd->crd_flags |= CRD_F_ENCRYPT;
302		crd->crd_alg = sc->sc_ealgo;
303		crd->crd_key = g_eli_key_hold(sc, dstoff, secsize);
304		crd->crd_klen = sc->sc_ekeylen;
305		if (sc->sc_ealgo == CRYPTO_AES_XTS)
306			crd->crd_klen <<= 1;
307		g_eli_crypto_ivgen(sc, dstoff, crd->crd_iv,
308		    sizeof(crd->crd_iv));
309		crd->crd_next = NULL;
310
311		crp->crp_etype = 0;
312		error = crypto_dispatch(crp);
313		KASSERT(error == 0, ("crypto_dispatch() failed (error=%d)",
314		    error));
315	}
316}
317