isohybrid: create a C version

Some Linux distributions have complained about Perl as a prerequisite
for isohybrid, so create a C version.

[ hpa: modified the array generator to put it all in one script ]

4 files changed, 653 insertions, 2 deletions

diff --git a/utils/Makefile b/utils/Makefile
index 7fdf631d..5930b991 100644
--- a/utils/Makefile
+++ b/utils/Makefile
@@ -21,6 +21,7 @@ CFLAGS   = $(GCCWARN) -Os -fomit-frame-pointer -D_FILE_OFFSET_BITS=64
 LDFLAGS  = -O2 -s
 
 TARGETS	 = mkdiskimage isohybrid gethostip
+TARGETS += isohybrid.pl  # about to be obsoleted
 ASIS     = keytab-lilo lss16toppm md5pass ppmtolss16 sha1pass syslinux2ansi \
 	   pxelinux-options
 
@@ -36,16 +37,23 @@ mkdiskimage: mkdiskimage.in ../mbr/mbr.bin bin2hex.pl
 	$(PERL) bin2hex.pl < ../mbr/mbr.bin | cat mkdiskimage.in - > $@
 	chmod a+x $@
 
-isohybrid: isohybrid.in $(ISOHDPFX) bin2hex.pl
+# Works on anything with a Perl interpreter...
+isohybrid.pl: isohybrid.in $(ISOHDPFX) bin2hex.pl
 	cp -f isohybrid.in $@
 	for f in $(ISOHDPFX) ; do $(PERL) bin2hex.pl < $$f >> $@ ; done
 	chmod a+x $@
 
+isohdpfx.c: $(ISOHDPFX) isohdpfxarray.pl
+	$(PERL) isohdpfxarray.pl $(ISOHDPFX) > $@
+
+isohybrid: isohybrid.c isohdpfx.c isohybrid.h
+	$(CC) $(UMAKEDEPS) $(CFLGAS) -o $@ isohybrid.c isohdpfx.c
+
 gethostip: gethostip.o
 	$(CC) $(LDFLAGS) -o $@ $^
 
 tidy dist:
-	rm -f *.o .*.d
+	rm -f *.o .*.d isohdpfx.c
 
 clean: tidy
 	rm -f $(TARGETS)
diff --git a/utils/isohdpfxarray.pl b/utils/isohdpfxarray.pl
new file mode 100644
index 00000000..06c71bff
--- /dev/null
+++ b/utils/isohdpfxarray.pl
@@ -0,0 +1,57 @@
+#!/usr/bin/perl
+## -----------------------------------------------------------------------
+##
+##   Copyright (C) 2010 P J P <pj.pandit@yahoo.co.in>
+##
+##   Permission is hereby granted, free of charge, to any person
+##   obtaining a copy of this software and associated documentation
+##   files (the "Software"), to deal in the Software without
+##   restriction, including without limitation the rights to use,
+##   copy, modify, merge, publish, distribute, sublicense, and/or
+##   sell copies of the Software, and to permit persons to whom
+##   the Software is furnished to do so, subject to the following
+##   conditions:
+##
+##   The above copyright notice and this permission notice shall
+##   be included in all copies or substantial portions of the Software.
+##
+##   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+##   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+##   OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+##   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+##   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+##   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+##   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+##   OTHER DEALINGS IN THE SOFTWARE.
+##
+## -----------------------------------------------------------------------
+
+use strict;
+use warnings;
+
+binmode STDIN;
+
+print "#include <inttypes.h>\n";
+print "#include \"isohybrid.h\"\n";
+print "\n";
+print "uint8_t isohdpfx[][MBRSIZE] =\n";
+print "{\n";
+
+foreach my $file (@ARGV) {
+    my $len = 0;
+    my $ch;
+
+    open(IN, '<', $file) or die "$0: $file: $!\n";
+    printf("    {\n");
+    while (read(IN, $ch, 1))
+    {
+	printf("\t/* 0x%03x */ ", $len) if (!($len % 8));
+	printf("0x%02x,", ord($ch));
+	$len++;
+    
+	print("\n") if (!($len % 8));
+    }
+    print "    },\n";
+    close(IN);
+}
+print "};\n";
diff --git a/utils/isohybrid.c b/utils/isohybrid.c
new file mode 100644
index 00000000..5b63b0c6
--- /dev/null
+++ b/utils/isohybrid.c
@@ -0,0 +1,559 @@
+/*
+ * isohybrid.c: Post process an ISO 9660 image generated with mkisofs or
+ * genisoimage to allow - hybrid booting - as a CD-ROM or as a hard
+ * disk.
+ *
+ * This is based on the original Perl script written by H. Peter Anvin. The
+ * rewrite in C is to avoid dependency on Perl on a system under installation.
+ *
+ * Copyright (C) 2010 P J P <pj.pandit@yahoo.co.in>
+ *
+ * isohybrid is a free software; you can redistribute it and/or modify it
+ * under the terms of GNU General Public License as published by Free Software
+ * Foundation; either version 2 of the license, or (at your option) any later
+ * version.
+ *
+ * isohybrid is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with isohybrid; if not, see: <http://www.gnu.org/licenses>.
+ *
+ */
+
+#include <err.h>
+#include <time.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <alloca.h>
+#include <getopt.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <inttypes.h>
+
+#include "isohybrid.h"
+
+char *prog = NULL;
+extern int opterr, optind;
+
+uint8_t mode = 0;
+enum { VERBOSE = 1 };
+
+/* user options */
+uint16_t head = 64;             /* 1 <= head <= 256 */
+uint8_t sector = 32;            /* 1 <= sector <= 63  */
+
+uint8_t entry = 1;              /* partition number: 1 <= entry <= 4 */
+uint8_t offset = 0;             /* partition offset: 0 <= offset <= 64 */
+uint16_t type = 0x17;           /* partition type: 0 <= type <= 255 */
+uint32_t id = 0;                /* MBR: 0 <= id <= 0xFFFFFFFF(4294967296) */
+
+uint8_t hd0 = 0;                /* 0 <= hd0 <= 2 */
+uint8_t partok = 0;             /* 0 <= partok <= 1 */
+
+uint16_t ve[16];
+uint32_t catoffset = 0;
+uint32_t c = 0, cc = 0, cs = 0;
+
+/* boot catalogue parameters */
+uint32_t de_lba = 0;
+uint16_t de_seg = 0, de_count = 0, de_mbz2 = 0;
+uint8_t de_boot = 0, de_media = 0, de_sys = 0, de_mbz1 = 0;
+
+
+void
+usage(void)
+{
+    printf("Usage: %s [OPTIONS] <boot.iso>\n", prog);
+}
+
+
+void
+printh(void)
+{
+#define FMT "%-18s %s\n"
+
+    usage();
+
+    printf("\n");
+    printf("Options:\n");
+    printf(FMT, "   -h <X>", "Number of default geometry heads");
+    printf(FMT, "   -s <X>", "Number of default geometry sectors");
+    printf(FMT, "   -e --entry", "Specify partition entry number (1-4)");
+    printf(FMT, "   -o --offset", "Specify partition offset (default 0)");
+    printf(FMT, "   -t --type", "Specify partition type (default 0x17)");
+    printf(FMT, "   -i --id", "Specify MBR ID (default random)");
+
+    printf("\n");
+    printf(FMT, "   --forcehd0", "Assume we are loaded as disk ID 0");
+    printf(FMT, "   --ctrlhd0", "Assume disk ID 0 if the Ctrl key is pressed");
+    printf(FMT, "   --partok", "Allow booting from within a partition");
+
+    printf("\n");
+    printf(FMT, "   -? --help", "Display this help");
+    printf(FMT, "   -v --verbose", "Display verbose output");
+    printf(FMT, "   -V --version", "Display version information");
+
+    printf("\n");
+    printf("Report bugs to <pj.pandit@yahoo.co.in>\n");
+}
+
+
+int
+check_option(int argc, char *argv[])
+{
+    int n = 0, ind = 0;
+
+    const char optstr[] = ":h:s:e:o:t:i:fcp?vV";
+    struct option lopt[] = \
+    {
+        { "entry", required_argument, NULL, 'e' },
+        { "offset", required_argument, NULL, 'o' },
+        { "type", required_argument, NULL, 't' },
+        { "id", required_argument, NULL, 'i' },
+
+        { "forcehd0", no_argument, NULL, 'f' },
+        { "ctrlhd0", no_argument, NULL, 'c' },
+        { "partok", no_argument, NULL, 'p'},
+
+        { "help", no_argument, NULL, '?' },
+        { "verbose", no_argument, NULL, 'v' },
+        { "version", no_argument, NULL, 'V' },
+
+        { 0, 0, 0, 0 }
+    };
+
+    opterr = mode = 0;
+    while ((n = getopt_long(argc, argv, optstr, lopt, &ind)) != -1)
+    {
+        switch (n)
+        {
+        case 'h':
+            if (!sscanf(optarg, "%hu", &head) || head < 1 || head > 256)
+                errx(1, "invalid head: `%s', 1 <= head <= 256", optarg);
+            break;
+
+        case 's':
+            if (!sscanf(optarg, "%hhu", &sector) || sector < 1 || sector > 63)
+                errx(1, "invalid sector: `%s', 1 <= sector <= 63", optarg);
+            break;
+
+        case 'e':
+            if (!sscanf(optarg, "%hhu", &entry) || entry < 1 || entry > 4)
+                errx(1, "invalid entry: `%s', 1 <= entry <= 4", optarg);
+            break;
+
+        case 'o':
+            if (!sscanf(optarg, "%hhu", &offset) || offset > 64)
+                errx(1, "invalid offset: `%s', 0 <= offset <= 64", optarg);
+            break;
+
+        case 't':
+            if (!sscanf(optarg, "%hu", &type) || type > 255)
+                errx(1, "invalid type: `%s', 0 <= type <= 255", optarg);
+            break;
+
+        case 'i':
+            if (!sscanf(optarg, "%u", &id))
+                errx(1, "invalid id: `%s'", optarg);
+            break;
+
+        case 'f':
+            hd0 = 1;
+            break;
+
+        case 'c':
+            hd0 = 2;
+            break;
+
+        case 'p':
+            partok = 1;
+            break;
+
+        case 'v':
+            mode |= VERBOSE;
+            break;
+
+        case 'V':
+            printf("%s version %s\n", prog, VERSION);
+            exit(0);
+
+        case ':':
+            errx(1, "option `-%c' takes an argument", optopt);
+
+        default:
+        case '?':
+            if (optopt)
+                errx(1, "invalid option `-%c', see --help", optopt);
+
+            printh();
+            exit(0);
+        }
+    }
+
+    return optind;
+}
+
+
+uint16_t
+lendian_short(const uint16_t s)
+{
+    uint16_t r = 1;
+
+    if (*(uint8_t *)&r)
+        return s;
+
+    r = (s & 0x00FF) << 8 | (s & 0xFF00) >> 8;
+
+    return r;
+}
+
+
+uint32_t
+lendian_int(const uint32_t s)
+{
+    uint32_t r = 1;
+
+    if (*(uint8_t *)&r)
+        return s;
+
+    r = (s & 0x000000FF) << 24 | (s & 0xFF000000) >> 24
+        | (s & 0x0000FF00) << 8 | (s & 0x00FF0000) >> 8;
+
+    return r;
+}
+
+
+int
+check_banner(const uint8_t *buf)
+{
+    static const char banner[] = "\0CD001\1EL TORITO SPECIFICATION\0\0\0\0" \
+        "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" \
+        "\0\0\0\0\0";
+
+    if (!buf || memcmp(buf, banner, sizeof(banner) - 1))
+        return 1;
+
+    buf += sizeof(banner) - 1;
+    memcpy(&catoffset, buf, sizeof(catoffset));
+
+    catoffset = lendian_int(catoffset);
+
+    return 0;
+}
+
+
+int
+check_catalogue(const uint8_t *buf)
+{
+    int i = 0;
+
+    for (i = 0, cs = 0; i < 16; i++)
+    {
+        ve[i] = 0;
+        memcpy(&ve[i], buf, sizeof(ve[i]));
+
+        ve[i] = lendian_short(ve[i]);
+
+        buf += 2;
+        cs += ve[i];
+
+        if (mode & VERBOSE)
+            printf("ve[%d]: %d, cs: %d\n", i, ve[i], cs);
+    }
+    if ((ve[0] != 0x0001) || (ve[15] != 0xAA55) || (cs & 0xFFFF))
+        return 1;
+
+    return 0;
+}
+
+
+int
+read_catalogue(const uint8_t *buf)
+{
+    memcpy(&de_boot, buf++, 1);
+    memcpy(&de_media, buf++, 1);
+
+    memcpy(&de_seg, buf, 2);
+    de_seg = lendian_short(de_seg);
+    buf += 2;
+
+    memcpy(&de_sys, buf++, 1);
+    memcpy(&de_mbz1, buf++, 1);
+
+    memcpy(&de_count, buf, 2);
+    de_count = lendian_short(de_count);
+    buf += 2;
+
+    memcpy(&de_lba, buf, 4);
+    de_lba = lendian_int(de_lba);
+    buf += 4;
+
+    memcpy(&de_mbz2, buf, 2);
+    de_mbz2 = lendian_short(de_mbz2);
+    buf += 2;
+
+    if (de_boot != 0x88 || de_media != 0
+        || (de_seg != 0 && de_seg != 0x7C0) || de_count != 4)
+        return 1;
+
+    return 0;
+}
+
+
+void
+display_catalogue(void)
+{
+    printf("de_boot: %hhu\n", de_boot);
+    printf("de_media: %hhu\n", de_media);
+    printf("de_seg: %hu\n", de_seg);
+    printf("de_sys: %hhu\n", de_sys);
+    printf("de_mbz1: %hhu\n", de_mbz1);
+    printf("de_count: %hu\n", de_count);
+    printf("de_lba: %u\n", de_lba);
+    printf("de_mbz2: %hu\n", de_mbz2);
+}
+
+
+int
+initialise_mbr(uint8_t *mbr)
+{
+    int i = 0;
+    uint32_t psize = 0, tmp = 0;
+    uint8_t ptype = 0, *rbm = mbr;
+    uint8_t bhead = 0, bsect = 0, bcyle = 0;
+    uint8_t ehead = 0, esect = 0, ecyle = 0;
+
+    extern unsigned char isohdpfx[][MBRSIZE];
+
+    memcpy(mbr, &isohdpfx[hd0 + 3 * partok], MBRSIZE);
+    mbr += MBRSIZE;                                 /* offset 432 */
+
+    tmp = lendian_int(de_lba * 4);
+    memcpy(mbr, &tmp, sizeof(tmp));
+    mbr += sizeof(tmp);                             /* offset 436 */
+
+    tmp = 0;
+    memcpy(mbr, &tmp, sizeof(tmp));
+    mbr += sizeof(tmp);                             /* offset 440 */
+
+    tmp = lendian_int(id);
+    memcpy(mbr, &tmp, sizeof(tmp));
+    mbr += sizeof(tmp);                             /* offset 444 */
+
+    mbr[0] = '\0';
+    mbr[1] = '\0';
+    mbr += 2;                                       /* offset 446 */
+
+    ptype = type;
+    psize = c * head * sector - offset;
+
+    bhead = (offset / sector) % head;
+    bsect = (offset % sector) + 1;
+    bcyle = offset / (head * sector);
+
+    bsect += (bcyle & 0x300) >> 2;
+    bcyle  &= 0xFF;
+
+    ehead = head - 1;
+    esect = sector + (((cc - 1) & 0x300) >> 2);
+    ecyle = (cc - 1) & 0xFF;
+
+    for (i = 1; i <= 4; i++)
+    {
+        memset(mbr, 0, 16);
+        if (i == entry)
+        {
+            mbr[0] = 0x80;
+            mbr[1] = bhead;
+            mbr[2] = bsect;
+            mbr[3] = bcyle;
+            mbr[4] = ptype;
+            mbr[5] = ehead;
+            mbr[6] = esect;
+            mbr[7] = ecyle;
+
+            tmp = lendian_int(offset);
+            memcpy(&mbr[8], &tmp, sizeof(tmp));
+
+            tmp = lendian_int(psize);
+            memcpy(&mbr[12], &tmp, sizeof(tmp));
+        }
+        mbr += 16;
+    }
+    mbr[0] = 0x55;
+    mbr[1] = 0xAA;
+    mbr += 2;
+
+    return mbr - rbm;
+}
+
+
+void
+display_mbr(const uint8_t *mbr, size_t len)
+{
+    unsigned char c = 0;
+    unsigned int i = 0, j = 0;
+
+    printf("sizeof(MBR): %d bytes\n", len);
+    for (i = 0; i < len; i++)
+    {
+        if (!(i % 16))
+            printf("%04d ", i);
+
+        if (!(i % 8))
+            printf(" ");
+
+        c = mbr[i];
+        printf("%02x ", c);
+
+        if (!((i + 1) % 16))
+        {
+            printf(" |");
+            for (; j <= i; j++)
+                printf("%c", isprint(mbr[j]) ? mbr[j] : '.');
+            printf("|\n");
+        }
+    }
+}
+
+
+int
+main(int argc, char *argv[])
+{
+    int i = 0;
+    FILE *fp = NULL;
+    struct stat isostat;
+    uint8_t *buf = NULL, *bufz = NULL;
+    int cylsize = 0, frac = 0, padding = 0;
+
+    prog = strcpy(alloca(strlen(argv[0]) + 1), argv[0]);
+    i = check_option(argc, argv);
+    argc -= i;
+    argv += i;
+
+    if (!argc)
+    {
+        usage();
+        return 1;
+    }
+    srand(time(NULL) << (getppid() << getpid()));
+
+    if (!(fp = fopen(argv[0], "r+")))
+        err(1, "could not open file `%s'", argv[0]);
+    if (fseek(fp, 17 * 2048, SEEK_SET))
+        err(1, "%s: seek error - 1", argv[0]);
+
+    bufz = buf = calloc(BUFSIZE, sizeof(char));
+    if (fread(buf, sizeof(char), BUFSIZE, fp) != BUFSIZE)
+        err(1, "%s", argv[0]);
+
+    if (check_banner(buf))
+        errx(1, "%s: could not find boot record", argv[0]);
+
+    if (mode & VERBOSE)
+        printf("catalogue offset: %d\n", catoffset);
+
+    if (fseek(fp, catoffset * 2048, SEEK_SET))
+        err(1, "%s: seek error - 2", argv[0]);
+
+    buf = bufz;
+    memset(buf, 0, BUFSIZE);
+    if (fread(buf, sizeof(char), BUFSIZE, fp) != BUFSIZE)
+        err(1, "%s", argv[0]);
+
+    if (check_catalogue(buf))
+        errx(1, "%s: invalid boot catalogue", argv[0]);
+
+    buf += sizeof(ve);
+    if (read_catalogue(buf))
+        errx(1, "%s: unexpected boot catalogue parameters", argv[0]);
+
+    if (mode & VERBOSE)
+        display_catalogue();
+
+    if (fseek(fp, (de_lba * 2048 + 0x40), SEEK_SET))
+        err(1, "%s: seek error - 3", argv[0]);
+
+    buf = bufz;
+    memset(buf, 0, BUFSIZE);
+    if (fread(buf, sizeof(char), 4, fp) != 4)
+        err(1, "%s", argv[0]);
+
+    if (memcmp(buf, "\xFB\xC0\x78\x70", 4))
+        errx(1, "%s: boot loader does not have an isolinux.bin hybrid " \
+                 "signature. Note that isolinux-debug.bin does not support " \
+                 "hybrid booting", argv[0]);
+
+    if (stat(argv[0], &isostat))
+        err(1, "%s", argv[0]);
+
+    cylsize = head * sector * 512;
+    frac = isostat.st_size % cylsize;
+    padding = (frac > 0) ? cylsize - frac : 0;
+
+    if (mode & VERBOSE)
+        printf("imgsize: %lu, padding: %d\n", isostat.st_size, padding);
+
+    cc = c = (isostat.st_size + padding) / cylsize;
+    if (c > 1024)
+    {
+        warnx("Warning: more than 1024 cylinders: %d", c);
+        warnx("Not all BIOSes will be able to boot this device");
+        cc = 1024;
+    }
+
+    if (!id)
+    {
+        if (fseek(fp, 440, SEEK_SET))
+            err(1, "%s: seek error - 4", argv[0]);
+
+        fscanf(fp, "%4c", &id);
+        id = lendian_int(id);
+        if (!id)
+        {
+            if (mode & VERBOSE)
+                printf("random ");
+            id = rand();
+        }
+    }
+    if (mode & VERBOSE)
+        printf("id: %u\n", id);
+
+    buf = bufz;
+    memset(buf, 0, BUFSIZE);
+    i = initialise_mbr(buf);
+
+    if (mode & VERBOSE)
+        display_mbr(buf, i);
+
+    if (fseek(fp, 0, SEEK_SET))
+        err(1, "%s: seek error - 5", argv[0]);
+
+    if (fwrite(buf, sizeof(char), i, fp) != (size_t)i)
+        err(1, "%s: write error - 1", argv[0]);
+
+    if (padding)
+    {
+        if (!(buf = realloc(buf, padding)))
+            err(1, "%s: could not re-size buffer", argv[0]);
+
+        if (fseek(fp, isostat.st_size, SEEK_SET))
+            err(1, "%s: seek error - 6", argv[0]);
+
+        memset(buf, 0, padding);
+        if (fwrite(buf, sizeof(char), padding, fp) != (size_t)padding)
+            err(1, "%s: write error - 2", argv[0]);
+    }
+
+    free(buf);
+    fclose(fp);
+
+    return 0;
+}
diff --git a/utils/isohybrid.h b/utils/isohybrid.h
new file mode 100644
index 00000000..826e90c5
--- /dev/null
+++ b/utils/isohybrid.h
@@ -0,0 +1,27 @@
+/*
+ * isohybrid.h: header file for isohybrid.c: Post process an ISO 9660 image
+ * generated with mkisofs or genisoimage to allow - hybrid booting - as a
+ * CD-ROM or as a hard disk.
+ *
+ * Copyright (C) 2010 Geert Stappers <stappers@stappers.nl>
+ *
+ * isohybrid is a free software; you can redistribute it and/or modify it
+ * under the terms of GNU General Public License as published by Free Software
+ * Foundation; either version 2 of the license, or (at your option) any later
+ * version.
+ *
+ * isohybrid is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with isohybrid; if not, see: <http://www.gnu.org/licenses>.
+ *
+ */
+
+#define VERSION     "0.11"
+#define BUFSIZE     2048
+#define MBRSIZE      432
+
+/* End of header file */