Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 | /*
* Makes a prep bootable image which can be dd'd onto
* a disk device to make a bootdisk. Will take
* as input a elf executable, strip off the header
* and write out a boot image as:
* 1) default - strips elf header
* suitable as a network boot image
* 2) -pbp - strips elf header and writes out prep boot partition image
* cat or dd onto disk for booting
* 3) -asm - strips elf header and writes out as asm data
* useful for generating data for a compressed image
* -- Cort
*
* Modified for x86 hosted builds by Matt Porter <porter@neta.com>
* Modified for Sparc hosted builds by Peter Wahl <PeterWahl@web.de>
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
/* size of read buffer */
#define SIZE 0x1000
/*
* Partition table entry
* - from the PReP spec
*/
typedef struct partition_entry {
unsigned char boot_indicator;
unsigned char starting_head;
unsigned char starting_sector;
unsigned char starting_cylinder;
unsigned char system_indicator;
unsigned char ending_head;
unsigned char ending_sector;
unsigned char ending_cylinder;
unsigned char beginning_sector[4];
unsigned char number_of_sectors[4];
} partition_entry_t;
#define BootActive 0x80
#define SystemPrep 0x41
void copy_image(FILE *, FILE *);
void write_prep_partition(FILE *, FILE *);
void write_asm_data(FILE *, FILE *);
unsigned int elfhdr_size = 65536;
int main(int argc, char *argv[])
{
FILE *in, *out;
int argptr = 1;
int prep = 0;
int asmoutput = 0;
if (argc < 3 || argc > 4) {
fprintf(stderr, "usage: %s [-pbp] [-asm] <boot-file> <image>\n",
argv[0]);
exit(-1);
}
/* needs to handle args more elegantly -- but this is a small/simple program */
/* check for -pbp */
if (!strcmp(argv[argptr], "-pbp")) {
prep = 1;
argptr++;
}
/* check for -asm */
if (!strcmp(argv[argptr], "-asm")) {
asmoutput = 1;
argptr++;
}
/* input file */
if (!strcmp(argv[argptr], "-"))
in = stdin;
else if (!(in = fopen(argv[argptr], "r")))
exit(-1);
argptr++;
/* output file */
if (!strcmp(argv[argptr], "-"))
out = stdout;
else if (!(out = fopen(argv[argptr], "w")))
exit(-1);
argptr++;
/* skip elf header in input file */
/*if ( !prep )*/
fseek(in, elfhdr_size, SEEK_SET);
/* write prep partition if necessary */
if (prep)
write_prep_partition(in, out);
/* write input image to bootimage */
if (asmoutput)
write_asm_data(in, out);
else
copy_image(in, out);
return 0;
}
void store_le32(unsigned int v, unsigned char *p)
{
p[0] = v;
p[1] = v >>= 8;
p[2] = v >>= 8;
p[3] = v >> 8;
}
void write_prep_partition(FILE *in, FILE *out)
{
unsigned char block[512];
partition_entry_t pe;
unsigned char *entry = block;
unsigned char *length = block + 4;
long pos = ftell(in), size;
if (fseek(in, 0, SEEK_END) < 0) {
fprintf(stderr,"info failed\n");
exit(-1);
}
size = ftell(in);
if (fseek(in, pos, SEEK_SET) < 0) {
fprintf(stderr,"info failed\n");
exit(-1);
}
memset(block, '\0', sizeof(block));
/* set entry point and boot image size skipping over elf header */
store_le32(0x400/*+65536*/, entry);
store_le32(size-elfhdr_size+0x400, length);
/* sets magic number for msdos partition (used by linux) */
block[510] = 0x55;
block[511] = 0xAA;
/*
* Build a "PReP" partition table entry in the boot record
* - "PReP" may only look at the system_indicator
*/
pe.boot_indicator = BootActive;
pe.system_indicator = SystemPrep;
/*
* The first block of the diskette is used by this "boot record" which
* actually contains the partition table. (The first block of the
* partition contains the boot image, but I digress...) We'll set up
* one partition on the diskette and it shall contain the rest of the
* diskette.
*/
pe.starting_head = 0; /* zero-based */
pe.starting_sector = 2; /* one-based */
pe.starting_cylinder = 0; /* zero-based */
pe.ending_head = 1; /* assumes two heads */
pe.ending_sector = 18; /* assumes 18 sectors/track */
pe.ending_cylinder = 79; /* assumes 80 cylinders/diskette */
/*
* The "PReP" software ignores the above fields and just looks at
* the next two.
* - size of the diskette is (assumed to be)
* (2 tracks/cylinder)(18 sectors/tracks)(80 cylinders/diskette)
* - unlike the above sector numbers, the beginning sector is zero-based!
*/
#if 0
store_le32(1, pe.beginning_sector);
#else
/* This has to be 0 on the PowerStack? */
store_le32(0, pe.beginning_sector);
#endif
store_le32(2*18*80-1, pe.number_of_sectors);
memcpy(&block[0x1BE], &pe, sizeof(pe));
fwrite(block, sizeof(block), 1, out);
fwrite(entry, 4, 1, out);
fwrite(length, 4, 1, out);
/* set file position to 2nd sector where image will be written */
fseek( out, 0x400, SEEK_SET );
}
void copy_image(FILE *in, FILE *out)
{
char buf[SIZE];
int n;
while ( (n = fread(buf, 1, SIZE, in)) > 0 )
fwrite(buf, 1, n, out);
}
void
write_asm_data(FILE *in, FILE *out)
{
int i, cnt, pos = 0;
unsigned int cksum = 0, val;
unsigned char *lp;
unsigned char buf[SIZE];
size_t len;
fputs("\t.data\n\t.globl input_data\ninput_data:\n", out);
while ((len = fread(buf, 1, sizeof(buf), in)) > 0) {
cnt = 0;
lp = buf;
/* Round up to longwords */
while (len & 3)
buf[len++] = '\0';
for (i = 0; i < len; i += 4) {
if (cnt == 0)
fputs("\t.long\t", out);
fprintf(out, "0x%02X%02X%02X%02X",
lp[0], lp[1], lp[2], lp[3]);
val = *(unsigned long *)lp;
cksum ^= val;
lp += 4;
if (++cnt == 4) {
cnt = 0;
fprintf(out, " # %x \n", pos+i-12);
} else {
fputs(",", out);
}
}
if (cnt)
fputs("0\n", out);
pos += len;
}
fprintf(out, "\t.globl input_len\ninput_len:\t.long\t0x%x\n", pos);
fprintf(stderr, "cksum = %x\n", cksum);
}
|