g_eli_privacy.c revision 220922
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: head/sys/geom/eli/g_eli_privacy.c 220922 2011-04-21 13:31:43Z pjd $"); 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/uio.h> 45#include <sys/vnode.h> 46 47#include <vm/uma.h> 48 49#include <geom/geom.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 61MALLOC_DECLARE(M_ELI); 62 63/* 64 * The function is called after we read and decrypt data. 65 * 66 * 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 67 */ 68static int 69g_eli_crypto_read_done(struct cryptop *crp) 70{ 71 struct g_eli_softc *sc; 72 struct bio *bp; 73 74 if (crp->crp_etype == EAGAIN) { 75 if (g_eli_crypto_rerun(crp) == 0) 76 return (0); 77 } 78 bp = (struct bio *)crp->crp_opaque; 79 bp->bio_inbed++; 80 if (crp->crp_etype == 0) { 81 G_ELI_DEBUG(3, "Crypto READ request done (%d/%d).", 82 bp->bio_inbed, bp->bio_children); 83 bp->bio_completed += crp->crp_olen; 84 } else { 85 G_ELI_DEBUG(1, "Crypto READ request failed (%d/%d) error=%d.", 86 bp->bio_inbed, bp->bio_children, crp->crp_etype); 87 if (bp->bio_error == 0) 88 bp->bio_error = crp->crp_etype; 89 } 90 sc = bp->bio_to->geom->softc; 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 atomic_subtract_int(&sc->sc_inflight, 1); 109 return (0); 110} 111 112/* 113 * The function is called after data encryption. 114 * 115 * g_eli_start -> g_eli_crypto_run -> G_ELI_CRYPTO_WRITE_DONE -> g_io_request -> g_eli_write_done -> g_io_deliver 116 */ 117static int 118g_eli_crypto_write_done(struct cryptop *crp) 119{ 120 struct g_eli_softc *sc; 121 struct g_geom *gp; 122 struct g_consumer *cp; 123 struct bio *bp, *cbp; 124 125 if (crp->crp_etype == EAGAIN) { 126 if (g_eli_crypto_rerun(crp) == 0) 127 return (0); 128 } 129 bp = (struct bio *)crp->crp_opaque; 130 bp->bio_inbed++; 131 if (crp->crp_etype == 0) { 132 G_ELI_DEBUG(3, "Crypto WRITE request done (%d/%d).", 133 bp->bio_inbed, bp->bio_children); 134 } else { 135 G_ELI_DEBUG(1, "Crypto WRITE request failed (%d/%d) error=%d.", 136 bp->bio_inbed, bp->bio_children, crp->crp_etype); 137 if (bp->bio_error == 0) 138 bp->bio_error = crp->crp_etype; 139 } 140 gp = bp->bio_to->geom; 141 sc = gp->softc; 142 g_eli_key_drop(sc, crp->crp_desc->crd_key); 143 /* 144 * All sectors are already encrypted? 145 */ 146 if (bp->bio_inbed < bp->bio_children) 147 return (0); 148 bp->bio_inbed = 0; 149 bp->bio_children = 1; 150 cbp = bp->bio_driver1; 151 bp->bio_driver1 = NULL; 152 if (bp->bio_error != 0) { 153 G_ELI_LOGREQ(0, bp, "Crypto WRITE request failed (error=%d).", 154 bp->bio_error); 155 free(bp->bio_driver2, M_ELI); 156 bp->bio_driver2 = NULL; 157 g_destroy_bio(cbp); 158 g_io_deliver(bp, bp->bio_error); 159 atomic_subtract_int(&sc->sc_inflight, 1); 160 return (0); 161 } 162 cbp->bio_data = bp->bio_driver2; 163 cbp->bio_done = g_eli_write_done; 164 cp = LIST_FIRST(&gp->consumer); 165 cbp->bio_to = cp->provider; 166 G_ELI_LOGREQ(2, cbp, "Sending request."); 167 /* 168 * Send encrypted data to the provider. 169 */ 170 g_io_request(cbp, cp); 171 return (0); 172} 173 174/* 175 * The function is called to read encrypted data. 176 * 177 * 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 178 */ 179void 180g_eli_crypto_read(struct g_eli_softc *sc, struct bio *bp, boolean_t fromworker) 181{ 182 struct g_consumer *cp; 183 struct bio *cbp; 184 185 if (!fromworker) { 186 /* 187 * We are not called from the worker thread, so check if 188 * device is suspended. 189 */ 190 mtx_lock(&sc->sc_queue_mtx); 191 if (sc->sc_flags & G_ELI_FLAG_SUSPEND) { 192 /* 193 * If device is suspended, we place the request onto 194 * the queue, so it can be handled after resume. 195 */ 196 G_ELI_DEBUG(0, "device suspended, move onto queue"); 197 bioq_insert_tail(&sc->sc_queue, bp); 198 mtx_unlock(&sc->sc_queue_mtx); 199 wakeup(sc); 200 return; 201 } 202 atomic_add_int(&sc->sc_inflight, 1); 203 mtx_unlock(&sc->sc_queue_mtx); 204 } 205 bp->bio_pflags = 0; 206 bp->bio_driver2 = NULL; 207 cbp = bp->bio_driver1; 208 cbp->bio_done = g_eli_read_done; 209 cp = LIST_FIRST(&sc->sc_geom->consumer); 210 cbp->bio_to = cp->provider; 211 G_ELI_LOGREQ(2, cbp, "Sending request."); 212 /* 213 * Read encrypted data from provider. 214 */ 215 g_io_request(cbp, cp); 216} 217 218/* 219 * This is the main function responsible for cryptography (ie. communication 220 * with crypto(9) subsystem). 221 * 222 * BIO_READ: 223 * 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 224 * BIO_WRITE: 225 * g_eli_start -> G_ELI_CRYPTO_RUN -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver 226 */ 227void 228g_eli_crypto_run(struct g_eli_worker *wr, struct bio *bp) 229{ 230 struct g_eli_softc *sc; 231 struct cryptop *crp; 232 struct cryptodesc *crd; 233 struct uio *uio; 234 struct iovec *iov; 235 u_int i, nsec, secsize; 236 int err, error; 237 off_t dstoff; 238 size_t size; 239 u_char *p, *data; 240 241 G_ELI_LOGREQ(3, bp, "%s", __func__); 242 243 bp->bio_pflags = wr->w_number; 244 sc = wr->w_softc; 245 secsize = LIST_FIRST(&sc->sc_geom->provider)->sectorsize; 246 nsec = bp->bio_length / secsize; 247 248 /* 249 * Calculate how much memory do we need. 250 * We need separate crypto operation for every single sector. 251 * It is much faster to calculate total amount of needed memory here and 252 * do the allocation once instead of allocating memory in pieces (many, 253 * many pieces). 254 */ 255 size = sizeof(*crp) * nsec; 256 size += sizeof(*crd) * nsec; 257 size += sizeof(*uio) * nsec; 258 size += sizeof(*iov) * nsec; 259 /* 260 * If we write the data we cannot destroy current bio_data content, 261 * so we need to allocate more memory for encrypted data. 262 */ 263 if (bp->bio_cmd == BIO_WRITE) 264 size += bp->bio_length; 265 p = malloc(size, M_ELI, M_WAITOK); 266 267 bp->bio_inbed = 0; 268 bp->bio_children = nsec; 269 bp->bio_driver2 = p; 270 271 if (bp->bio_cmd == BIO_READ) 272 data = bp->bio_data; 273 else { 274 data = p; 275 p += bp->bio_length; 276 bcopy(bp->bio_data, data, bp->bio_length); 277 } 278 279 error = 0; 280 for (i = 0, dstoff = bp->bio_offset; i < nsec; i++, dstoff += secsize) { 281 crp = (struct cryptop *)p; p += sizeof(*crp); 282 crd = (struct cryptodesc *)p; p += sizeof(*crd); 283 uio = (struct uio *)p; p += sizeof(*uio); 284 iov = (struct iovec *)p; p += sizeof(*iov); 285 286 iov->iov_len = secsize; 287 iov->iov_base = data; 288 data += secsize; 289 290 uio->uio_iov = iov; 291 uio->uio_iovcnt = 1; 292 uio->uio_segflg = UIO_SYSSPACE; 293 uio->uio_resid = secsize; 294 295 crp->crp_sid = wr->w_sid; 296 crp->crp_ilen = secsize; 297 crp->crp_olen = secsize; 298 crp->crp_opaque = (void *)bp; 299 crp->crp_buf = (void *)uio; 300 if (bp->bio_cmd == BIO_WRITE) 301 crp->crp_callback = g_eli_crypto_write_done; 302 else /* if (bp->bio_cmd == BIO_READ) */ 303 crp->crp_callback = g_eli_crypto_read_done; 304 crp->crp_flags = CRYPTO_F_IOV | CRYPTO_F_CBIFSYNC | CRYPTO_F_REL; 305 if (g_eli_batch) 306 crp->crp_flags |= CRYPTO_F_BATCH; 307 crp->crp_desc = crd; 308 309 crd->crd_skip = 0; 310 crd->crd_len = secsize; 311 crd->crd_flags = CRD_F_IV_EXPLICIT | CRD_F_IV_PRESENT; 312 if ((sc->sc_flags & G_ELI_FLAG_SINGLE_KEY) == 0) 313 crd->crd_flags |= CRD_F_KEY_EXPLICIT; 314 if (bp->bio_cmd == BIO_WRITE) 315 crd->crd_flags |= CRD_F_ENCRYPT; 316 crd->crd_alg = sc->sc_ealgo; 317 crd->crd_key = g_eli_key_hold(sc, dstoff, secsize); 318 crd->crd_klen = sc->sc_ekeylen; 319 if (sc->sc_ealgo == CRYPTO_AES_XTS) 320 crd->crd_klen <<= 1; 321 g_eli_crypto_ivgen(sc, dstoff, crd->crd_iv, 322 sizeof(crd->crd_iv)); 323 crd->crd_next = NULL; 324 325 crp->crp_etype = 0; 326 err = crypto_dispatch(crp); 327 if (error == 0) 328 error = err; 329 } 330 if (bp->bio_error == 0) 331 bp->bio_error = error; 332} 333