diff options
Diffstat (limited to 'usr.sbin/boot0cfg/boot0cfg.c')
-rw-r--r-- | usr.sbin/boot0cfg/boot0cfg.c | 607 |
1 files changed, 607 insertions, 0 deletions
diff --git a/usr.sbin/boot0cfg/boot0cfg.c b/usr.sbin/boot0cfg/boot0cfg.c new file mode 100644 index 0000000..f2cbf67 --- /dev/null +++ b/usr.sbin/boot0cfg/boot0cfg.c @@ -0,0 +1,607 @@ +/* + * 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> +__FBSDID("$FreeBSD$"); + +#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 = sizeof(opttbl) / sizeof(opttbl[0]); + +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); +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); + +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); + + /* + * 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); + + /* 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); + } + *mbr = malloc(sizeof(buf)); + if (*mbr == 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) +{ + 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"); + 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 if (geom_class_available("MBR") != 0) { + grq = gctl_get_handle(); + gctl_ro_param(grq, "verb", -1, "write MBR"); + gctl_ro_param(grq, "class", -1, "MBR"); + gctl_ro_param(grq, "geom", -1, pname); + gctl_ro_param(grq, "data", mbr_size, mbr); + errmsg = gctl_issue(grq); + if (errmsg != NULL) + err(1, "GEOM_MBR: write MBR to %s failed", fname); + 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); +} |