1 /* $NetBSD: cgd.c,v 1.52 2008/04/28 20:23:46 martin Exp $ */ 2 3 /*- 4 * Copyright (c) 2002 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Roland C. Dowdeswell. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: cgd.c,v 1.52 2008/04/28 20:23:46 martin Exp $"); 34 35 #include <sys/types.h> 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/proc.h> 39 #include <sys/errno.h> 40 #include <sys/buf.h> 41 #include <sys/bufq.h> 42 #include <sys/malloc.h> 43 #include <sys/pool.h> 44 #include <sys/ioctl.h> 45 #include <sys/device.h> 46 #include <sys/disk.h> 47 #include <sys/disklabel.h> 48 #include <sys/fcntl.h> 49 #include <sys/vnode.h> 50 #include <sys/conf.h> 51 52 #include <dev/dkvar.h> 53 #include <dev/cgdvar.h> 54 55 /* Entry Point Functions */ 56 57 void cgdattach(int); 58 59 static dev_type_open(cgdopen); 60 static dev_type_close(cgdclose); 61 static dev_type_read(cgdread); 62 static dev_type_write(cgdwrite); 63 static dev_type_ioctl(cgdioctl); 64 static dev_type_strategy(cgdstrategy); 65 static dev_type_dump(cgddump); 66 static dev_type_size(cgdsize); 67 68 const struct bdevsw cgd_bdevsw = { 69 cgdopen, cgdclose, cgdstrategy, cgdioctl, 70 cgddump, cgdsize, D_DISK 71 }; 72 73 const struct cdevsw cgd_cdevsw = { 74 cgdopen, cgdclose, cgdread, cgdwrite, cgdioctl, 75 nostop, notty, nopoll, nommap, nokqfilter, D_DISK 76 }; 77 78 /* Internal Functions */ 79 80 static int cgdstart(struct dk_softc *, struct buf *); 81 static void cgdiodone(struct buf *); 82 83 static int cgd_ioctl_set(struct cgd_softc *, void *, struct lwp *); 84 static int cgd_ioctl_clr(struct cgd_softc *, void *, struct lwp *); 85 static int cgdinit(struct cgd_softc *, const char *, struct vnode *, 86 struct lwp *); 87 static void cgd_cipher(struct cgd_softc *, void *, void *, 88 size_t, daddr_t, size_t, int); 89 90 /* Pseudo-disk Interface */ 91 92 static struct dk_intf the_dkintf = { 93 DTYPE_CGD, 94 "cgd", 95 cgdopen, 96 cgdclose, 97 cgdstrategy, 98 cgdstart, 99 }; 100 static struct dk_intf *di = &the_dkintf; 101 102 static struct dkdriver cgddkdriver = { 103 .d_strategy = cgdstrategy, 104 .d_minphys = minphys, 105 }; 106 107 /* DIAGNOSTIC and DEBUG definitions */ 108 109 #if defined(CGDDEBUG) && !defined(DEBUG) 110 #define DEBUG 111 #endif 112 113 #ifdef DEBUG 114 int cgddebug = 0; 115 116 #define CGDB_FOLLOW 0x1 117 #define CGDB_IO 0x2 118 #define CGDB_CRYPTO 0x4 119 120 #define IFDEBUG(x,y) if (cgddebug & (x)) y 121 #define DPRINTF(x,y) IFDEBUG(x, printf y) 122 #define DPRINTF_FOLLOW(y) DPRINTF(CGDB_FOLLOW, y) 123 124 static void hexprint(const char *, void *, int); 125 126 #else 127 #define IFDEBUG(x,y) 128 #define DPRINTF(x,y) 129 #define DPRINTF_FOLLOW(y) 130 #endif 131 132 #ifdef DIAGNOSTIC 133 #define DIAGPANIC(x) panic x 134 #define DIAGCONDPANIC(x,y) if (x) panic y 135 #else 136 #define DIAGPANIC(x) 137 #define DIAGCONDPANIC(x,y) 138 #endif 139 140 /* Global variables */ 141 142 struct cgd_softc *cgd_softc; 143 int numcgd = 0; 144 145 /* Utility Functions */ 146 147 #define CGDUNIT(x) DISKUNIT(x) 148 #define GETCGD_SOFTC(_cs, x) if (!((_cs) = getcgd_softc(x))) return ENXIO 149 150 static struct cgd_softc * 151 getcgd_softc(dev_t dev) 152 { 153 int unit = CGDUNIT(dev); 154 155 DPRINTF_FOLLOW(("getcgd_softc(0x%x): unit = %d\n", dev, unit)); 156 if (unit >= numcgd) 157 return NULL; 158 return &cgd_softc[unit]; 159 } 160 161 /* The code */ 162 163 static void 164 cgdsoftc_init(struct cgd_softc *cs, int num) 165 { 166 char sbuf[DK_XNAME_SIZE]; 167 168 memset(cs, 0x0, sizeof(*cs)); 169 snprintf(sbuf, DK_XNAME_SIZE, "cgd%d", num); 170 simple_lock_init(&cs->sc_slock); 171 dk_sc_init(&cs->sc_dksc, cs, sbuf); 172 disk_init(&cs->sc_dksc.sc_dkdev, cs->sc_dksc.sc_xname, &cgddkdriver); 173 } 174 175 void 176 cgdattach(int num) 177 { 178 int i; 179 180 DPRINTF_FOLLOW(("cgdattach(%d)\n", num)); 181 if (num <= 0) { 182 DIAGPANIC(("cgdattach: count <= 0")); 183 return; 184 } 185 186 cgd_softc = (void *)malloc(num * sizeof(*cgd_softc), M_DEVBUF, M_NOWAIT); 187 if (!cgd_softc) { 188 printf("WARNING: unable to malloc(9) memory for crypt disks\n"); 189 DIAGPANIC(("cgdattach: cannot malloc(9) enough memory")); 190 return; 191 } 192 193 numcgd = num; 194 for (i=0; i<num; i++) 195 cgdsoftc_init(&cgd_softc[i], i); 196 } 197 198 static int 199 cgdopen(dev_t dev, int flags, int fmt, struct lwp *l) 200 { 201 struct cgd_softc *cs; 202 203 DPRINTF_FOLLOW(("cgdopen(%d, %d)\n", dev, flags)); 204 GETCGD_SOFTC(cs, dev); 205 return dk_open(di, &cs->sc_dksc, dev, flags, fmt, l); 206 } 207 208 static int 209 cgdclose(dev_t dev, int flags, int fmt, struct lwp *l) 210 { 211 struct cgd_softc *cs; 212 213 DPRINTF_FOLLOW(("cgdclose(%d, %d)\n", dev, flags)); 214 GETCGD_SOFTC(cs, dev); 215 return dk_close(di, &cs->sc_dksc, dev, flags, fmt, l); 216 } 217 218 static void 219 cgdstrategy(struct buf *bp) 220 { 221 struct cgd_softc *cs = getcgd_softc(bp->b_dev); 222 223 DPRINTF_FOLLOW(("cgdstrategy(%p): b_bcount = %ld\n", bp, 224 (long)bp->b_bcount)); 225 /* XXXrcd: Should we test for (cs != NULL)? */ 226 dk_strategy(di, &cs->sc_dksc, bp); 227 return; 228 } 229 230 static int 231 cgdsize(dev_t dev) 232 { 233 struct cgd_softc *cs = getcgd_softc(dev); 234 235 DPRINTF_FOLLOW(("cgdsize(%d)\n", dev)); 236 if (!cs) 237 return -1; 238 return dk_size(di, &cs->sc_dksc, dev); 239 } 240 241 /* 242 * cgd_{get,put}data are functions that deal with getting a buffer 243 * for the new encrypted data. We have a buffer per device so that 244 * we can ensure that we can always have a transaction in flight. 245 * We use this buffer first so that we have one less piece of 246 * malloc'ed data at any given point. 247 */ 248 249 static void * 250 cgd_getdata(struct dk_softc *dksc, unsigned long size) 251 { 252 struct cgd_softc *cs =dksc->sc_osc; 253 void * data = NULL; 254 255 simple_lock(&cs->sc_slock); 256 if (cs->sc_data_used == 0) { 257 cs->sc_data_used = 1; 258 data = cs->sc_data; 259 } 260 simple_unlock(&cs->sc_slock); 261 262 if (data) 263 return data; 264 265 return malloc(size, M_DEVBUF, M_NOWAIT); 266 } 267 268 static void 269 cgd_putdata(struct dk_softc *dksc, void *data) 270 { 271 struct cgd_softc *cs =dksc->sc_osc; 272 273 if (data == cs->sc_data) { 274 simple_lock(&cs->sc_slock); 275 cs->sc_data_used = 0; 276 simple_unlock(&cs->sc_slock); 277 } else { 278 free(data, M_DEVBUF); 279 } 280 } 281 282 static int 283 cgdstart(struct dk_softc *dksc, struct buf *bp) 284 { 285 struct cgd_softc *cs = dksc->sc_osc; 286 struct buf *nbp; 287 void * addr; 288 void * newaddr; 289 daddr_t bn; 290 struct vnode *vp; 291 292 DPRINTF_FOLLOW(("cgdstart(%p, %p)\n", dksc, bp)); 293 disk_busy(&dksc->sc_dkdev); /* XXX: put in dksubr.c */ 294 295 bn = bp->b_rawblkno; 296 297 /* 298 * We attempt to allocate all of our resources up front, so that 299 * we can fail quickly if they are unavailable. 300 */ 301 302 nbp = getiobuf(cs->sc_tvn, false); 303 if (nbp == NULL) { 304 disk_unbusy(&dksc->sc_dkdev, 0, (bp->b_flags & B_READ)); 305 return -1; 306 } 307 308 /* 309 * If we are writing, then we need to encrypt the outgoing 310 * block into a new block of memory. If we fail, then we 311 * return an error and let the dksubr framework deal with it. 312 */ 313 newaddr = addr = bp->b_data; 314 if ((bp->b_flags & B_READ) == 0) { 315 newaddr = cgd_getdata(dksc, bp->b_bcount); 316 if (!newaddr) { 317 putiobuf(nbp); 318 disk_unbusy(&dksc->sc_dkdev, 0, (bp->b_flags & B_READ)); 319 return -1; 320 } 321 cgd_cipher(cs, newaddr, addr, bp->b_bcount, bn, 322 DEV_BSIZE, CGD_CIPHER_ENCRYPT); 323 } 324 325 nbp->b_data = newaddr; 326 nbp->b_flags = bp->b_flags; 327 nbp->b_oflags = bp->b_oflags; 328 nbp->b_cflags = bp->b_cflags; 329 nbp->b_iodone = cgdiodone; 330 nbp->b_proc = bp->b_proc; 331 nbp->b_blkno = bn; 332 nbp->b_bcount = bp->b_bcount; 333 nbp->b_private = bp; 334 335 BIO_COPYPRIO(nbp, bp); 336 337 if ((nbp->b_flags & B_READ) == 0) { 338 vp = nbp->b_vp; 339 mutex_enter(&vp->v_interlock); 340 vp->v_numoutput++; 341 mutex_exit(&vp->v_interlock); 342 } 343 VOP_STRATEGY(cs->sc_tvn, nbp); 344 return 0; 345 } 346 347 /* expected to be called at splbio() */ 348 static void 349 cgdiodone(struct buf *nbp) 350 { 351 struct buf *obp = nbp->b_private; 352 struct cgd_softc *cs = getcgd_softc(obp->b_dev); 353 struct dk_softc *dksc = &cs->sc_dksc; 354 355 KDASSERT(cs); 356 357 DPRINTF_FOLLOW(("cgdiodone(%p)\n", nbp)); 358 DPRINTF(CGDB_IO, ("cgdiodone: bp %p bcount %d resid %d\n", 359 obp, obp->b_bcount, obp->b_resid)); 360 DPRINTF(CGDB_IO, (" dev 0x%x, nbp %p bn %" PRId64 " addr %p bcnt %d\n", 361 nbp->b_dev, nbp, nbp->b_blkno, nbp->b_data, 362 nbp->b_bcount)); 363 if (nbp->b_error != 0) { 364 obp->b_error = nbp->b_error; 365 printf("%s: error %d\n", dksc->sc_xname, obp->b_error); 366 } 367 368 /* Perform the decryption if we are reading. 369 * 370 * Note: use the blocknumber from nbp, since it is what 371 * we used to encrypt the blocks. 372 */ 373 374 if (nbp->b_flags & B_READ) 375 cgd_cipher(cs, obp->b_data, obp->b_data, obp->b_bcount, 376 nbp->b_blkno, DEV_BSIZE, CGD_CIPHER_DECRYPT); 377 378 /* If we allocated memory, free it now... */ 379 if (nbp->b_data != obp->b_data) 380 cgd_putdata(dksc, nbp->b_data); 381 382 putiobuf(nbp); 383 384 /* Request is complete for whatever reason */ 385 obp->b_resid = 0; 386 if (obp->b_error != 0) 387 obp->b_resid = obp->b_bcount; 388 disk_unbusy(&dksc->sc_dkdev, obp->b_bcount - obp->b_resid, 389 (obp->b_flags & B_READ)); 390 biodone(obp); 391 dk_iodone(di, dksc); 392 } 393 394 /* XXX: we should probably put these into dksubr.c, mostly */ 395 static int 396 cgdread(dev_t dev, struct uio *uio, int flags) 397 { 398 struct cgd_softc *cs; 399 struct dk_softc *dksc; 400 401 DPRINTF_FOLLOW(("cgdread(%d, %p, %d)\n", dev, uio, flags)); 402 GETCGD_SOFTC(cs, dev); 403 dksc = &cs->sc_dksc; 404 if ((dksc->sc_flags & DKF_INITED) == 0) 405 return ENXIO; 406 return physio(cgdstrategy, NULL, dev, B_READ, minphys, uio); 407 } 408 409 /* XXX: we should probably put these into dksubr.c, mostly */ 410 static int 411 cgdwrite(dev_t dev, struct uio *uio, int flags) 412 { 413 struct cgd_softc *cs; 414 struct dk_softc *dksc; 415 416 DPRINTF_FOLLOW(("cgdwrite(%d, %p, %d)\n", dev, uio, flags)); 417 GETCGD_SOFTC(cs, dev); 418 dksc = &cs->sc_dksc; 419 if ((dksc->sc_flags & DKF_INITED) == 0) 420 return ENXIO; 421 return physio(cgdstrategy, NULL, dev, B_WRITE, minphys, uio); 422 } 423 424 static int 425 cgdioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l) 426 { 427 struct cgd_softc *cs; 428 struct dk_softc *dksc; 429 struct disk *dk; 430 int ret; 431 int part = DISKPART(dev); 432 int pmask = 1 << part; 433 434 DPRINTF_FOLLOW(("cgdioctl(%d, %ld, %p, %d, %p)\n", 435 dev, cmd, data, flag, l)); 436 GETCGD_SOFTC(cs, dev); 437 dksc = &cs->sc_dksc; 438 dk = &dksc->sc_dkdev; 439 switch (cmd) { 440 case CGDIOCSET: 441 case CGDIOCCLR: 442 if ((flag & FWRITE) == 0) 443 return EBADF; 444 } 445 446 switch (cmd) { 447 case CGDIOCSET: 448 if (dksc->sc_flags & DKF_INITED) 449 ret = EBUSY; 450 else 451 ret = cgd_ioctl_set(cs, data, l); 452 break; 453 case CGDIOCCLR: 454 if (!(dksc->sc_flags & DKF_INITED)) { 455 ret = ENXIO; 456 break; 457 } 458 if (DK_BUSY(&cs->sc_dksc, pmask)) { 459 ret = EBUSY; 460 break; 461 } 462 ret = cgd_ioctl_clr(cs, data, l); 463 break; 464 default: 465 ret = dk_ioctl(di, dksc, dev, cmd, data, flag, l); 466 break; 467 } 468 469 return ret; 470 } 471 472 static int 473 cgddump(dev_t dev, daddr_t blkno, void *va, size_t size) 474 { 475 struct cgd_softc *cs; 476 477 DPRINTF_FOLLOW(("cgddump(%d, %" PRId64 ", %p, %lu)\n", dev, blkno, va, 478 (unsigned long)size)); 479 GETCGD_SOFTC(cs, dev); 480 return dk_dump(di, &cs->sc_dksc, dev, blkno, va, size); 481 } 482 483 /* 484 * XXXrcd: 485 * for now we hardcode the maximum key length. 486 */ 487 #define MAX_KEYSIZE 1024 488 489 /* ARGSUSED */ 490 static int 491 cgd_ioctl_set(struct cgd_softc *cs, void *data, struct lwp *l) 492 { 493 struct cgd_ioctl *ci = data; 494 struct vnode *vp; 495 int ret; 496 size_t keybytes; /* key length in bytes */ 497 const char *cp; 498 char *inbuf; 499 500 cp = ci->ci_disk; 501 if ((ret = dk_lookup(cp, l, &vp, UIO_USERSPACE)) != 0) 502 return ret; 503 504 inbuf = malloc(MAX_KEYSIZE, M_TEMP, M_WAITOK); 505 506 if ((ret = cgdinit(cs, cp, vp, l)) != 0) 507 goto bail; 508 509 (void)memset(inbuf, 0, MAX_KEYSIZE); 510 ret = copyinstr(ci->ci_alg, inbuf, 256, NULL); 511 if (ret) 512 goto bail; 513 cs->sc_cfuncs = cryptfuncs_find(inbuf); 514 if (!cs->sc_cfuncs) { 515 ret = EINVAL; 516 goto bail; 517 } 518 519 /* right now we only support encblkno, so hard-code it */ 520 (void)memset(inbuf, 0, MAX_KEYSIZE); 521 ret = copyinstr(ci->ci_ivmethod, inbuf, MAX_KEYSIZE, NULL); 522 if (ret) 523 goto bail; 524 if (strcmp("encblkno", inbuf)) { 525 ret = EINVAL; 526 goto bail; 527 } 528 529 keybytes = ci->ci_keylen / 8 + 1; 530 if (keybytes > MAX_KEYSIZE) { 531 ret = EINVAL; 532 goto bail; 533 } 534 (void)memset(inbuf, 0, MAX_KEYSIZE); 535 ret = copyin(ci->ci_key, inbuf, keybytes); 536 if (ret) 537 goto bail; 538 539 cs->sc_cdata.cf_blocksize = ci->ci_blocksize; 540 cs->sc_cdata.cf_mode = CGD_CIPHER_CBC_ENCBLKNO; 541 cs->sc_cdata.cf_priv = cs->sc_cfuncs->cf_init(ci->ci_keylen, inbuf, 542 &cs->sc_cdata.cf_blocksize); 543 (void)memset(inbuf, 0, MAX_KEYSIZE); 544 if (!cs->sc_cdata.cf_priv) { 545 printf("cgd: unable to initialize cipher\n"); 546 ret = EINVAL; /* XXX is this the right error? */ 547 goto bail; 548 } 549 free(inbuf, M_TEMP); 550 551 bufq_alloc(&cs->sc_dksc.sc_bufq, "fcfs", 0); 552 553 cs->sc_data = malloc(MAXPHYS, M_DEVBUF, M_WAITOK); 554 cs->sc_data_used = 0; 555 556 cs->sc_dksc.sc_flags |= DKF_INITED; 557 558 /* Attach the disk. */ 559 disk_attach(&cs->sc_dksc.sc_dkdev); 560 561 /* Try and read the disklabel. */ 562 dk_getdisklabel(di, &cs->sc_dksc, 0 /* XXX ? */); 563 564 /* Discover wedges on this disk. */ 565 dkwedge_discover(&cs->sc_dksc.sc_dkdev); 566 567 return 0; 568 569 bail: 570 free(inbuf, M_TEMP); 571 (void)vn_close(vp, FREAD|FWRITE, l->l_cred); 572 return ret; 573 } 574 575 /* ARGSUSED */ 576 static int 577 cgd_ioctl_clr(struct cgd_softc *cs, void *data, struct lwp *l) 578 { 579 int s; 580 581 /* Delete all of our wedges. */ 582 dkwedge_delall(&cs->sc_dksc.sc_dkdev); 583 584 /* Kill off any queued buffers. */ 585 s = splbio(); 586 bufq_drain(cs->sc_dksc.sc_bufq); 587 splx(s); 588 bufq_free(cs->sc_dksc.sc_bufq); 589 590 (void)vn_close(cs->sc_tvn, FREAD|FWRITE, l->l_cred); 591 cs->sc_cfuncs->cf_destroy(cs->sc_cdata.cf_priv); 592 free(cs->sc_tpath, M_DEVBUF); 593 free(cs->sc_data, M_DEVBUF); 594 cs->sc_data_used = 0; 595 cs->sc_dksc.sc_flags &= ~DKF_INITED; 596 disk_detach(&cs->sc_dksc.sc_dkdev); 597 598 return 0; 599 } 600 601 static int 602 cgdinit(struct cgd_softc *cs, const char *cpath, struct vnode *vp, 603 struct lwp *l) 604 { 605 struct dk_geom *pdg; 606 struct partinfo dpart; 607 struct vattr va; 608 size_t size; 609 int maxsecsize = 0; 610 int ret; 611 char *tmppath; 612 613 cs->sc_dksc.sc_size = 0; 614 cs->sc_tvn = vp; 615 cs->sc_tpath = NULL; 616 617 tmppath = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 618 ret = copyinstr(cpath, tmppath, MAXPATHLEN, &cs->sc_tpathlen); 619 if (ret) 620 goto bail; 621 cs->sc_tpath = malloc(cs->sc_tpathlen, M_DEVBUF, M_WAITOK); 622 memcpy(cs->sc_tpath, tmppath, cs->sc_tpathlen); 623 624 if ((ret = VOP_GETATTR(vp, &va, l->l_cred)) != 0) 625 goto bail; 626 627 cs->sc_tdev = va.va_rdev; 628 629 ret = VOP_IOCTL(vp, DIOCGPART, &dpart, FREAD, l->l_cred); 630 if (ret) 631 goto bail; 632 633 maxsecsize = 634 ((dpart.disklab->d_secsize > maxsecsize) ? 635 dpart.disklab->d_secsize : maxsecsize); 636 size = dpart.part->p_size; 637 638 if (!size) { 639 ret = ENODEV; 640 goto bail; 641 } 642 643 cs->sc_dksc.sc_size = size; 644 645 /* 646 * XXX here we should probe the underlying device. If we 647 * are accessing a partition of type RAW_PART, then 648 * we should populate our initial geometry with the 649 * geometry that we discover from the device. 650 */ 651 pdg = &cs->sc_dksc.sc_geom; 652 pdg->pdg_secsize = DEV_BSIZE; 653 pdg->pdg_ntracks = 1; 654 pdg->pdg_nsectors = 1024 * (1024 / pdg->pdg_secsize); 655 pdg->pdg_ncylinders = cs->sc_dksc.sc_size / pdg->pdg_nsectors; 656 657 bail: 658 free(tmppath, M_TEMP); 659 if (ret && cs->sc_tpath) 660 free(cs->sc_tpath, M_DEVBUF); 661 return ret; 662 } 663 664 /* 665 * Our generic cipher entry point. This takes care of the 666 * IV mode and passes off the work to the specific cipher. 667 * We implement here the IV method ``encrypted block 668 * number''. 669 * 670 * For the encryption case, we accomplish this by setting 671 * up a struct uio where the first iovec of the source is 672 * the blocknumber and the first iovec of the dest is a 673 * sink. We then call the cipher with an IV of zero, and 674 * the right thing happens. 675 * 676 * For the decryption case, we use the same basic mechanism 677 * for symmetry, but we encrypt the block number in the 678 * first iovec. 679 * 680 * We mainly do this to avoid requiring the definition of 681 * an ECB mode. 682 * 683 * XXXrcd: for now we rely on our own crypto framework defined 684 * in dev/cgd_crypto.c. This will change when we 685 * get a generic kernel crypto framework. 686 */ 687 688 static void 689 blkno2blkno_buf(char *sbuf, daddr_t blkno) 690 { 691 int i; 692 693 /* Set up the blkno in blkno_buf, here we do not care much 694 * about the final layout of the information as long as we 695 * can guarantee that each sector will have a different IV 696 * and that the endianness of the machine will not affect 697 * the representation that we have chosen. 698 * 699 * We choose this representation, because it does not rely 700 * on the size of buf (which is the blocksize of the cipher), 701 * but allows daddr_t to grow without breaking existing 702 * disks. 703 * 704 * Note that blkno2blkno_buf does not take a size as input, 705 * and hence must be called on a pre-zeroed buffer of length 706 * greater than or equal to sizeof(daddr_t). 707 */ 708 for (i=0; i < sizeof(daddr_t); i++) { 709 *sbuf++ = blkno & 0xff; 710 blkno >>= 8; 711 } 712 } 713 714 static void 715 cgd_cipher(struct cgd_softc *cs, void *dstv, void *srcv, 716 size_t len, daddr_t blkno, size_t secsize, int dir) 717 { 718 char *dst = dstv; 719 char *src = srcv; 720 cfunc_cipher *cipher = cs->sc_cfuncs->cf_cipher; 721 struct uio dstuio; 722 struct uio srcuio; 723 struct iovec dstiov[2]; 724 struct iovec srciov[2]; 725 size_t blocksize = cs->sc_cdata.cf_blocksize; 726 char sink[blocksize]; 727 char zero_iv[blocksize]; 728 char blkno_buf[blocksize]; 729 730 DPRINTF_FOLLOW(("cgd_cipher() dir=%d\n", dir)); 731 732 DIAGCONDPANIC(len % blocksize != 0, 733 ("cgd_cipher: len %% blocksize != 0")); 734 735 /* ensure that sizeof(daddr_t) <= blocksize (for encblkno IVing) */ 736 DIAGCONDPANIC(sizeof(daddr_t) > blocksize, 737 ("cgd_cipher: sizeof(daddr_t) > blocksize")); 738 739 memset(zero_iv, 0x0, sizeof(zero_iv)); 740 741 dstuio.uio_iov = dstiov; 742 dstuio.uio_iovcnt = 2; 743 744 srcuio.uio_iov = srciov; 745 srcuio.uio_iovcnt = 2; 746 747 dstiov[0].iov_base = sink; 748 dstiov[0].iov_len = blocksize; 749 srciov[0].iov_base = blkno_buf; 750 srciov[0].iov_len = blocksize; 751 dstiov[1].iov_len = secsize; 752 srciov[1].iov_len = secsize; 753 754 for (; len > 0; len -= secsize) { 755 dstiov[1].iov_base = dst; 756 srciov[1].iov_base = src; 757 758 memset(blkno_buf, 0x0, sizeof(blkno_buf)); 759 blkno2blkno_buf(blkno_buf, blkno); 760 if (dir == CGD_CIPHER_DECRYPT) { 761 dstuio.uio_iovcnt = 1; 762 srcuio.uio_iovcnt = 1; 763 IFDEBUG(CGDB_CRYPTO, hexprint("step 0: blkno_buf", 764 blkno_buf, sizeof(blkno_buf))); 765 cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio, 766 zero_iv, CGD_CIPHER_ENCRYPT); 767 memcpy(blkno_buf, sink, blocksize); 768 dstuio.uio_iovcnt = 2; 769 srcuio.uio_iovcnt = 2; 770 } 771 772 IFDEBUG(CGDB_CRYPTO, hexprint("step 1: blkno_buf", 773 blkno_buf, sizeof(blkno_buf))); 774 cipher(cs->sc_cdata.cf_priv, &dstuio, &srcuio, zero_iv, dir); 775 IFDEBUG(CGDB_CRYPTO, hexprint("step 2: sink", 776 sink, sizeof(sink))); 777 778 dst += secsize; 779 src += secsize; 780 blkno++; 781 } 782 } 783 784 #ifdef DEBUG 785 static void 786 hexprint(const char *start, void *buf, int len) 787 { 788 char *c = buf; 789 790 DIAGCONDPANIC(len < 0, ("hexprint: called with len < 0")); 791 printf("%s: len=%06d 0x", start, len); 792 while (len--) 793 printf("%02x", (unsigned char) *c++); 794 } 795 #endif 796