/* * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2008 Luigi Rizzo * Copyright (c) 1999 Robert Nordier * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include <sys/cdefs.h> #include <sys/param.h> #include <sys/disklabel.h> #include <sys/diskmbr.h> #include <sys/stat.h> #include <err.h> #include <errno.h> #include <fcntl.h> #include <libgeom.h> #include <paths.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #define MBRSIZE 512 /* master boot record size */ #define OFF_VERSION 0x1b0 /* offset: version number, only boot0version */ #define OFF_SERIAL 0x1b8 /* offset: volume serial number */ #define OFF_PTBL 0x1be /* offset: partition table */ #define OFF_MAGIC 0x1fe /* offset: magic number */ /* * Offsets to the parameters of the 512-byte boot block. * For historical reasons they are set as macros */ struct opt_offsets { int opt; int drive; int flags; int ticks; }; static struct opt_offsets b0_ofs[] = { { 0x0, 0x0, 0x0, 0x0 }, /* no boot block */ { 0x1b9, 0x1ba, 0x1bb, 0x1bc }, /* original block */ { 0x1b5, 0x1b6, 0x1b7, 0x1bc }, /* NT_SERIAL block */ }; static int b0_ver; /* boot block version set by boot0bs */ #define OFF_OPT (b0_ofs[b0_ver].opt) /* default boot option */ #define OFF_DRIVE (b0_ofs[b0_ver].drive) /* setdrv drive */ #define OFF_FLAGS (b0_ofs[b0_ver].flags) /* option flags */ #define OFF_TICKS (b0_ofs[b0_ver].ticks) /* clock ticks */ #define cv2(p) ((p)[0] | (p)[1] << 010) #define mk2(p, x) \ (p)[0] = (u_int8_t)(x), \ (p)[1] = (u_int8_t)((x) >> 010) static const struct { const char *tok; int def; } opttbl[] = { {"packet", 0}, {"update", 1}, {"setdrv", 0} }; static const int nopt = nitems(opttbl); static const char fmt0[] = "# flag start chs type" " end chs offset size\n"; static const char fmt1[] = "%d 0x%02x %4u:%3u:%2u 0x%02x" " %4u:%3u:%2u %10u %10u\n"; static int geom_class_available(const char *); static int read_mbr(const char *, u_int8_t **, int); static void write_mbr(const char *, int, u_int8_t *, int, int); static void display_mbr(u_int8_t *); static int boot0version(const u_int8_t *); static int boot0bs(const u_int8_t *); static void stropt(const char *, int *, int *); static int argtoi(const char *, int, int, int); static int set_bell(u_int8_t *, int, int); static void usage(void) __dead2; static unsigned vol_id[5]; /* 4 plus 1 for flag */ static int v_flag; /* * Boot manager installation/configuration utility. */ int main(int argc, char *argv[]) { u_int8_t *mbr, *boot0; int boot0_size, mbr_size; const char *bpath, *fpath; char *disk; int B_flag, o_flag; int d_arg, m_arg, s_arg, t_arg; int o_and, o_or, o_e = -1; int up, c; bpath = "/boot/boot0"; fpath = NULL; B_flag = v_flag = o_flag = 0; d_arg = m_arg = s_arg = t_arg = -1; o_and = 0xff; o_or = 0; while ((c = getopt(argc, argv, "Bvb:d:e:f:i:m:o:s:t:")) != -1) switch (c) { case 'B': B_flag = 1; break; case 'v': v_flag = 1; break; case 'b': bpath = optarg; break; case 'd': d_arg = argtoi(optarg, 0, 0xff, 'd'); break; case 'e': if (optarg[0] == '0' && optarg[1] == 'x') sscanf(optarg, "0x%02x", &o_e); else o_e = optarg[0]; break; case 'f': fpath = optarg; break; case 'i': if (sscanf(optarg, "%02x%02x-%02x%02x", vol_id, vol_id+1, vol_id+2, vol_id+3) == 4) vol_id[4] = 1; else errx(1, "bad argument %s", optarg); break; case 'm': m_arg = argtoi(optarg, 0, 0xf, 'm'); break; case 'o': stropt(optarg, &o_and, &o_or); o_flag = 1; break; case 's': if (strcasecmp(optarg, "pxe") == 0) s_arg = 6; else s_arg = argtoi(optarg, 1, 6, 's'); break; case 't': t_arg = argtoi(optarg, 1, 0xffff, 't'); break; default: usage(); } argc -= optind; argv += optind; if (argc != 1) usage(); disk = g_device_path(*argv); if (disk == NULL) errx(1, "Unable to get providername for %s\n", *argv); up = B_flag || d_arg != -1 || m_arg != -1 || o_flag || s_arg != -1 || t_arg != -1; /* open the disk and read in the existing mbr. Either here or * when reading the block from disk, we do check for the version * and abort if a suitable block is not found. */ mbr_size = read_mbr(disk, &mbr, !B_flag); /* save the existing MBR if we are asked to do so */ if (fpath) write_mbr(fpath, O_CREAT | O_TRUNC, mbr, mbr_size, 0); /* * If we are installing the boot loader, read it from disk and copy the * slice table over from the existing MBR. If not, then point boot0 * back at the MBR we just read in. After this, boot0 is the data to * write back to disk if we are going to do a write. */ if (B_flag) { boot0_size = read_mbr(bpath, &boot0, 1); memcpy(boot0 + OFF_PTBL, mbr + OFF_PTBL, sizeof(struct dos_partition) * NDOSPART); if (b0_ver == 2) /* volume serial number support */ memcpy(boot0 + OFF_SERIAL, mbr + OFF_SERIAL, 4); } else { boot0 = mbr; boot0_size = mbr_size; } /* set the drive */ if (d_arg != -1) boot0[OFF_DRIVE] = d_arg; /* set various flags */ if (m_arg != -1) { boot0[OFF_FLAGS] &= 0xf0; boot0[OFF_FLAGS] |= m_arg; } if (o_flag) { boot0[OFF_FLAGS] &= o_and; boot0[OFF_FLAGS] |= o_or; } /* set the default boot selection */ if (s_arg != -1) boot0[OFF_OPT] = s_arg - 1; /* set the timeout */ if (t_arg != -1) mk2(boot0 + OFF_TICKS, t_arg); /* set the bell char */ if (o_e != -1 && set_bell(boot0, o_e, 0) != -1) up = 1; if (vol_id[4]) { if (b0_ver != 2) errx(1, "incompatible boot block, cannot set volume ID"); boot0[OFF_SERIAL] = vol_id[0]; boot0[OFF_SERIAL+1] = vol_id[1]; boot0[OFF_SERIAL+2] = vol_id[2]; boot0[OFF_SERIAL+3] = vol_id[3]; up = 1; /* force update */ } /* write the MBR back to disk */ if (up) write_mbr(disk, 0, boot0, boot0_size, vol_id[4] || b0_ver == 1); /* display the MBR */ if (v_flag) display_mbr(boot0); /* clean up */ if (mbr != boot0) free(boot0); free(mbr); free(disk); return 0; } /* get or set the 'bell' character to be used in case of errors. * Lookup for a certain code sequence, return -1 if not found. */ static int set_bell(u_int8_t *mbr, int new_bell, int report) { /* lookup sequence: 0x100 means skip, 0x200 means done */ static unsigned seq[] = { 0xb0, 0x100, 0xe8, 0x100, 0x100, 0x30, 0xe4, 0x200 }; int ofs, i, c; for (ofs = 0x60; ofs < 0x180; ofs++) { /* search range */ if (mbr[ofs] != seq[0]) /* search initial pattern */ continue; for (i=0;; i++) { if (seq[i] == 0x200) { /* found */ c = mbr[ofs+1]; if (!report) mbr[ofs+1] = c = new_bell; else printf(" bell=%c (0x%x)", (c >= ' ' && c < 0x7f) ? c : ' ', c); return c; } if (seq[i] != 0x100 && seq[i] != mbr[ofs+i]) break; } } warn("bell not found"); return -1; } /* * Read in the MBR of the disk. If it is boot0, then use the version to * read in all of it if necessary. Use pointers to return a malloc'd * buffer containing the MBR and then return its size. */ static int read_mbr(const char *disk, u_int8_t **mbr, int check_version) { u_int8_t buf[MBRSIZE]; int mbr_size, fd; int ver; ssize_t n; if ((fd = open(disk, O_RDONLY)) == -1) err(1, "open %s", disk); if ((n = read(fd, buf, MBRSIZE)) == -1) err(1, "read %s", disk); if (n != MBRSIZE) errx(1, "%s: short read", disk); if (cv2(buf + OFF_MAGIC) != 0xaa55) errx(1, "%s: bad magic", disk); if (! (ver = boot0bs(buf))) { if (check_version) errx(1, "%s: unknown or incompatible boot code", disk); } else if (boot0version(buf) == 0x101) { mbr_size = 1024; if ((*mbr = malloc(mbr_size)) == NULL) errx(1, "%s: unable to allocate read buffer", disk); if (lseek(fd, 0, SEEK_SET) == -1 || (n = read(fd, *mbr, mbr_size)) == -1) err(1, "%s", disk); if (n != mbr_size) errx(1, "%s: short read", disk); close(fd); return (mbr_size); } if ((*mbr = malloc(sizeof(buf))) == NULL) errx(1, "%s: unable to allocate MBR buffer", disk); memcpy(*mbr, buf, sizeof(buf)); close(fd); return sizeof(buf); } static int geom_class_available(const char *name) { struct gclass *class; struct gmesh mesh; int error; error = geom_gettree(&mesh); if (error != 0) errc(1, error, "Cannot get GEOM tree"); LIST_FOREACH(class, &mesh.lg_class, lg_class) { if (strcmp(class->lg_name, name) == 0) { geom_deletetree(&mesh); return (1); } } geom_deletetree(&mesh); return (0); } /* * Write out the mbr to the specified file. */ static void write_mbr(const char *fname, int flags, u_int8_t *mbr, int mbr_size, int disable_dsn) { struct gctl_req *grq; const char *errmsg; char *pname; ssize_t n; int fd; fd = open(fname, O_WRONLY | flags, 0666); if (fd != -1) { n = write(fd, mbr, mbr_size); close(fd); if (n != mbr_size) errx(1, "%s: short write", fname); return; } /* * If we're called to write to a backup file, don't try to * write through GEOM. */ if (flags != 0) err(1, "can't open file %s to write backup", fname); /* Try open it read only. */ fd = open(fname, O_RDONLY); if (fd == -1) { warn("error opening %s", fname); return; } pname = g_providername(fd); if (pname == NULL) { warn("error getting providername for %s", fname); return; } /* First check that GEOM_PART is available */ if (geom_class_available("PART") != 0) { grq = gctl_get_handle(); gctl_ro_param(grq, "class", -1, "PART"); gctl_ro_param(grq, "arg0", -1, pname); gctl_ro_param(grq, "verb", -1, "bootcode"); gctl_ro_param(grq, "bootcode", mbr_size, mbr); gctl_ro_param(grq, "flags", -1, "C"); if (disable_dsn) gctl_ro_param(grq, "skip_dsn", sizeof(int), &disable_dsn); errmsg = gctl_issue(grq); if (errmsg != NULL && errmsg[0] != '\0') errx(1, "GEOM_PART: write bootcode to %s failed: %s", fname, errmsg); gctl_free(grq); } else errx(1, "can't write MBR to %s", fname); free(pname); } /* * Outputs an informative dump of the data in the MBR to stdout. */ static void display_mbr(u_int8_t *mbr) { struct dos_partition *part; int i, version; part = (struct dos_partition *)(mbr + DOSPARTOFF); printf(fmt0); for (i = 0; i < NDOSPART; i++) if (part[i].dp_typ) printf(fmt1, 1 + i, part[i].dp_flag, part[i].dp_scyl + ((part[i].dp_ssect & 0xc0) << 2), part[i].dp_shd, part[i].dp_ssect & 0x3f, part[i].dp_typ, part[i].dp_ecyl + ((part[i].dp_esect & 0xc0) << 2), part[i].dp_ehd, part[i].dp_esect & 0x3f, part[i].dp_start, part[i].dp_size); printf("\n"); version = boot0version(mbr); printf("version=%d.%d drive=0x%x mask=0x%x ticks=%u", version >> 8, version & 0xff, mbr[OFF_DRIVE], mbr[OFF_FLAGS] & 0xf, cv2(mbr + OFF_TICKS)); set_bell(mbr, 0, 1); printf("\noptions="); for (i = 0; i < nopt; i++) { if (i) printf(","); if (!(mbr[OFF_FLAGS] & 1 << (7 - i)) ^ opttbl[i].def) printf("no"); printf("%s", opttbl[i].tok); } printf("\n"); if (b0_ver == 2) printf("volume serial ID %02x%02x-%02x%02x\n", mbr[OFF_SERIAL], mbr[OFF_SERIAL+1], mbr[OFF_SERIAL+2], mbr[OFF_SERIAL+3]); printf("default_selection=F%d (", mbr[OFF_OPT] + 1); if (mbr[OFF_OPT] < 4) printf("Slice %d", mbr[OFF_OPT] + 1); else if (mbr[OFF_OPT] == 4) printf("Drive 1"); else printf("PXE"); printf(")\n"); } /* * Return the boot0 version with the minor revision in the low byte, and * the major revision in the next higher byte. */ static int boot0version(const u_int8_t *bs) { /* Check for old version, and return 0x100 if found. */ int v = boot0bs(bs); if (v != 0) return v << 8; /* We have a newer boot0, so extract the version number and return it. */ return *(const int *)(bs + OFF_VERSION) & 0xffff; } /* descriptor of a pattern to match. * Start from the first entry trying to match the chunk of bytes, * if you hit an entry with len=0 terminate the search and report * off as the version. Otherwise skip to the next block after len=0 * An entry with len=0, off=0 is the end marker. */ struct byte_pattern { unsigned off; unsigned len; u_int8_t *key; }; /* * Decide if we have valid boot0 boot code by looking for * characteristic byte sequences at fixed offsets. */ static int boot0bs(const u_int8_t *bs) { /* the initial code sequence */ static u_int8_t id0[] = {0xfc, 0x31, 0xc0, 0x8e, 0xc0, 0x8e, 0xd8, 0x8e, 0xd0, 0xbc, 0x00, 0x7c }; /* the drive id */ static u_int8_t id1[] = {'D', 'r', 'i', 'v', 'e', ' '}; static struct byte_pattern patterns[] = { {0x0, sizeof(id0), id0}, {0x1b2, sizeof(id1), id1}, {1, 0, NULL}, {0x0, sizeof(id0), id0}, /* version with NT support */ {0x1ae, sizeof(id1), id1}, {2, 0, NULL}, {0, 0, NULL}, }; struct byte_pattern *p = patterns; for (; p->off || p->len; p++) { if (p->len == 0) break; if (!memcmp(bs + p->off, p->key, p->len)) /* match */ continue; while (p->len) /* skip to next block */ p++; } b0_ver = p->off; /* XXX ugly side effect */ return p->off; } /* * Adjust "and" and "or" masks for a -o option argument. */ static void stropt(const char *arg, int *xa, int *xo) { const char *q; char *s, *s1; int inv, i, x; if (!(s = strdup(arg))) err(1, NULL); for (s1 = s; (q = strtok(s1, ",")); s1 = NULL) { if ((inv = !strncmp(q, "no", 2))) q += 2; for (i = 0; i < nopt; i++) if (!strcmp(q, opttbl[i].tok)) break; if (i == nopt) errx(1, "%s: Unknown -o option", q); if (opttbl[i].def) inv ^= 1; x = 1 << (7 - i); if (inv) *xa &= ~x; else *xo |= x; } free(s); } /* * Convert and check an option argument. */ static int argtoi(const char *arg, int lo, int hi, int opt) { char *s; long x; errno = 0; x = strtol(arg, &s, 0); if (errno || !*arg || *s || x < lo || x > hi) errx(1, "%s: Bad argument to -%c option", arg, opt); return x; } /* * Display usage information. */ static void usage(void) { fprintf(stderr, "%s\n%s\n", "usage: boot0cfg [-Bv] [-b boot0] [-d drive] [-f file] [-m mask]", " [-o options] [-s slice] [-t ticks] disk"); exit(1); }