g_eli_privacy.c revision 214118
1/*- 2 * Copyright (c) 2005-2010 Pawel Jakub Dawidek <pjd@FreeBSD.org> 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 214118 2010-10-20 20:50:55Z 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 /* 91 * Do we have all sectors already? 92 */ 93 if (bp->bio_inbed < bp->bio_children) 94 return (0); 95 free(bp->bio_driver2, M_ELI); 96 bp->bio_driver2 = NULL; 97 if (bp->bio_error != 0) { 98 G_ELI_LOGREQ(0, bp, "Crypto READ request failed (error=%d).", 99 bp->bio_error); 100 bp->bio_completed = 0; 101 } 102 /* 103 * Read is finished, send it up. 104 */ 105 sc = bp->bio_to->geom->softc; 106 g_io_deliver(bp, bp->bio_error); 107 atomic_subtract_int(&sc->sc_inflight, 1); 108 return (0); 109} 110 111/* 112 * The function is called after data encryption. 113 * 114 * g_eli_start -> g_eli_crypto_run -> G_ELI_CRYPTO_WRITE_DONE -> g_io_request -> g_eli_write_done -> g_io_deliver 115 */ 116static int 117g_eli_crypto_write_done(struct cryptop *crp) 118{ 119 struct g_eli_softc *sc; 120 struct g_geom *gp; 121 struct g_consumer *cp; 122 struct bio *bp, *cbp; 123 124 if (crp->crp_etype == EAGAIN) { 125 if (g_eli_crypto_rerun(crp) == 0) 126 return (0); 127 } 128 bp = (struct bio *)crp->crp_opaque; 129 bp->bio_inbed++; 130 if (crp->crp_etype == 0) { 131 G_ELI_DEBUG(3, "Crypto WRITE request done (%d/%d).", 132 bp->bio_inbed, bp->bio_children); 133 } else { 134 G_ELI_DEBUG(1, "Crypto WRITE request failed (%d/%d) error=%d.", 135 bp->bio_inbed, bp->bio_children, crp->crp_etype); 136 if (bp->bio_error == 0) 137 bp->bio_error = crp->crp_etype; 138 } 139 /* 140 * All sectors are already encrypted? 141 */ 142 if (bp->bio_inbed < bp->bio_children) 143 return (0); 144 bp->bio_inbed = 0; 145 bp->bio_children = 1; 146 cbp = bp->bio_driver1; 147 bp->bio_driver1 = NULL; 148 gp = bp->bio_to->geom; 149 if (bp->bio_error != 0) { 150 G_ELI_LOGREQ(0, bp, "Crypto WRITE request failed (error=%d).", 151 bp->bio_error); 152 free(bp->bio_driver2, M_ELI); 153 bp->bio_driver2 = NULL; 154 g_destroy_bio(cbp); 155 sc = gp->softc; 156 g_io_deliver(bp, bp->bio_error); 157 atomic_subtract_int(&sc->sc_inflight, 1); 158 return (0); 159 } 160 cbp->bio_data = bp->bio_driver2; 161 cbp->bio_done = g_eli_write_done; 162 cp = LIST_FIRST(&gp->consumer); 163 cbp->bio_to = cp->provider; 164 G_ELI_LOGREQ(2, cbp, "Sending request."); 165 /* 166 * Send encrypted data to the provider. 167 */ 168 g_io_request(cbp, cp); 169 return (0); 170} 171 172/* 173 * The function is called to read encrypted data. 174 * 175 * 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 176 */ 177void 178g_eli_crypto_read(struct g_eli_softc *sc, struct bio *bp, boolean_t fromworker) 179{ 180 struct g_consumer *cp; 181 struct bio *cbp; 182 183 if (!fromworker) { 184 /* 185 * We are not called from the worker thread, so check if 186 * device is suspended. 187 */ 188 mtx_lock(&sc->sc_queue_mtx); 189 if (sc->sc_flags & G_ELI_FLAG_SUSPEND) { 190 /* 191 * If device is suspended, we place the request onto 192 * the queue, so it can be handled after resume. 193 */ 194 G_ELI_DEBUG(0, "device suspended, move onto queue"); 195 bioq_insert_tail(&sc->sc_queue, bp); 196 mtx_unlock(&sc->sc_queue_mtx); 197 wakeup(sc); 198 return; 199 } 200 atomic_add_int(&sc->sc_inflight, 1); 201 mtx_unlock(&sc->sc_queue_mtx); 202 } 203 bp->bio_pflags = 0; 204 bp->bio_driver2 = NULL; 205 cbp = bp->bio_driver1; 206 cbp->bio_done = g_eli_read_done; 207 cp = LIST_FIRST(&sc->sc_geom->consumer); 208 cbp->bio_to = cp->provider; 209 G_ELI_LOGREQ(2, cbp, "Sending request."); 210 /* 211 * Read encrypted data from provider. 212 */ 213 g_io_request(cbp, cp); 214} 215 216/* 217 * This is the main function responsible for cryptography (ie. communication 218 * with crypto(9) subsystem). 219 * 220 * BIO_READ: 221 * 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 222 * BIO_WRITE: 223 * g_eli_start -> G_ELI_CRYPTO_RUN -> g_eli_crypto_write_done -> g_io_request -> g_eli_write_done -> g_io_deliver 224 */ 225void 226g_eli_crypto_run(struct g_eli_worker *wr, struct bio *bp) 227{ 228 struct g_eli_softc *sc; 229 struct cryptop *crp; 230 struct cryptodesc *crd; 231 struct uio *uio; 232 struct iovec *iov; 233 u_int i, nsec, secsize; 234 int err, error; 235 off_t dstoff; 236 size_t size; 237 u_char *p, *data; 238 239 G_ELI_LOGREQ(3, bp, "%s", __func__); 240 241 bp->bio_pflags = wr->w_number; 242 sc = wr->w_softc; 243 secsize = LIST_FIRST(&sc->sc_geom->provider)->sectorsize; 244 nsec = bp->bio_length / secsize; 245 246 /* 247 * Calculate how much memory do we need. 248 * We need separate crypto operation for every single sector. 249 * It is much faster to calculate total amount of needed memory here and 250 * do the allocation once instead of allocating memory in pieces (many, 251 * many pieces). 252 */ 253 size = sizeof(*crp) * nsec; 254 size += sizeof(*crd) * nsec; 255 size += sizeof(*uio) * nsec; 256 size += sizeof(*iov) * nsec; 257 /* 258 * If we write the data we cannot destroy current bio_data content, 259 * so we need to allocate more memory for encrypted data. 260 */ 261 if (bp->bio_cmd == BIO_WRITE) 262 size += bp->bio_length; 263 p = malloc(size, M_ELI, M_WAITOK); 264 265 bp->bio_inbed = 0; 266 bp->bio_children = nsec; 267 bp->bio_driver2 = p; 268 269 if (bp->bio_cmd == BIO_READ) 270 data = bp->bio_data; 271 else { 272 data = p; 273 p += bp->bio_length; 274 bcopy(bp->bio_data, data, bp->bio_length); 275 } 276 277 error = 0; 278 for (i = 0, dstoff = bp->bio_offset; i < nsec; i++, dstoff += secsize) { 279 crp = (struct cryptop *)p; p += sizeof(*crp); 280 crd = (struct cryptodesc *)p; p += sizeof(*crd); 281 uio = (struct uio *)p; p += sizeof(*uio); 282 iov = (struct iovec *)p; p += sizeof(*iov); 283 284 iov->iov_len = secsize; 285 iov->iov_base = data; 286 data += secsize; 287 288 uio->uio_iov = iov; 289 uio->uio_iovcnt = 1; 290 uio->uio_segflg = UIO_SYSSPACE; 291 uio->uio_resid = secsize; 292 293 crp->crp_sid = wr->w_sid; 294 crp->crp_ilen = secsize; 295 crp->crp_olen = secsize; 296 crp->crp_opaque = (void *)bp; 297 crp->crp_buf = (void *)uio; 298 if (bp->bio_cmd == BIO_WRITE) 299 crp->crp_callback = g_eli_crypto_write_done; 300 else /* if (bp->bio_cmd == BIO_READ) */ 301 crp->crp_callback = g_eli_crypto_read_done; 302 crp->crp_flags = CRYPTO_F_IOV | CRYPTO_F_CBIFSYNC | CRYPTO_F_REL; 303 if (g_eli_batch) 304 crp->crp_flags |= CRYPTO_F_BATCH; 305 crp->crp_desc = crd; 306 307 crd->crd_skip = 0; 308 crd->crd_len = secsize; 309 crd->crd_flags = CRD_F_IV_EXPLICIT | CRD_F_IV_PRESENT; 310 if (sc->sc_nekeys > 1) 311 crd->crd_flags |= CRD_F_KEY_EXPLICIT; 312 if (bp->bio_cmd == BIO_WRITE) 313 crd->crd_flags |= CRD_F_ENCRYPT; 314 crd->crd_alg = sc->sc_ealgo; 315 crd->crd_key = g_eli_crypto_key(sc, dstoff, secsize); 316 crd->crd_klen = sc->sc_ekeylen; 317 if (sc->sc_ealgo == CRYPTO_AES_XTS) 318 crd->crd_klen <<= 1; 319 g_eli_crypto_ivgen(sc, dstoff, crd->crd_iv, 320 sizeof(crd->crd_iv)); 321 crd->crd_next = NULL; 322 323 crp->crp_etype = 0; 324 err = crypto_dispatch(crp); 325 if (error == 0) 326 error = err; 327 } 328 if (bp->bio_error == 0) 329 bp->bio_error = error; 330} 331