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1/*
2 * Makes a prep bootable image which can be dd'd onto
3 * a disk device to make a bootdisk. Will take
4 * as input a elf executable, strip off the header
5 * and write out a boot image as:
6 * 1) default - strips elf header
7 * suitable as a network boot image
8 * 2) -pbp - strips elf header and writes out prep boot partition image
9 * cat or dd onto disk for booting
10 * 3) -asm - strips elf header and writes out as asm data
11 * useful for generating data for a compressed image
12 * -- Cort
13 *
14 * Modified for x86 hosted builds by Matt Porter <porter@neta.com>
15 * Modified for Sparc hosted builds by Peter Wahl <PeterWahl@web.de>
16 */
17
18#include <fcntl.h>
19#include <stdio.h>
20#include <stdlib.h>
21#include <string.h>
22#include <strings.h>
23#include <sys/stat.h>
24#include <unistd.h>
25
26#define cpu_to_le32(x) le32_to_cpu((x))
27unsigned long le32_to_cpu(unsigned long x)
28{
29 return (((x & 0x000000ffU) << 24) |
30 ((x & 0x0000ff00U) << 8) |
31 ((x & 0x00ff0000U) >> 8) |
32 ((x & 0xff000000U) >> 24));
33}
34
35
36#define cpu_to_le16(x) le16_to_cpu((x))
37unsigned short le16_to_cpu(unsigned short x)
38{
39 return (((x & 0x00ff) << 8) |
40 ((x & 0xff00) >> 8));
41}
42
43#define cpu_to_be32(x) (x)
44#define be32_to_cpu(x) (x)
45#define cpu_to_be16(x) (x)
46#define be16_to_cpu(x) (x)
47
48/* size of read buffer */
49#define SIZE 0x1000
50
51
52typedef unsigned long dword_t;
53typedef unsigned short word_t;
54typedef unsigned char byte_t;
55typedef byte_t block_t[512];
56typedef byte_t page_t[4096];
57
58
59/*
60 * Partition table entry
61 * - from the PReP spec
62 */
63typedef struct partition_entry {
64 byte_t boot_indicator;
65 byte_t starting_head;
66 byte_t starting_sector;
67 byte_t starting_cylinder;
68
69 byte_t system_indicator;
70 byte_t ending_head;
71 byte_t ending_sector;
72 byte_t ending_cylinder;
73
74 dword_t beginning_sector;
75 dword_t number_of_sectors;
76} partition_entry_t;
77
78#define BootActive 0x80
79#define SystemPrep 0x41
80
81void copy_image(int , int);
82void write_prep_partition(int , int );
83void write_asm_data( int in, int out );
84
85unsigned int elfhdr_size = 65536;
86
87int main(int argc, char *argv[])
88{
89 int in_fd, out_fd;
90 int argptr = 1;
91 unsigned int prep = 0;
92 unsigned int asmoutput = 0;
93
94 if ( (argc < 3) || (argc > 4) )
95 {
96 fprintf(stderr, "usage: %s [-pbp] [-asm] <boot-file> <image>\n",argv[0]);
97 exit(-1);
98 }
99
100 /* needs to handle args more elegantly -- but this is a small/simple program */
101
102 /* check for -pbp */
103 if ( !strcmp( argv[argptr], "-pbp" ) )
104 {
105 prep = 1;
106 argptr++;
107 }
108
109 /* check for -asm */
110 if ( !strcmp( argv[argptr], "-asm" ) )
111 {
112 asmoutput = 1;
113 argptr++;
114 }
115
116 /* input file */
117 if ( !strcmp( argv[argptr], "-" ) )
118 in_fd = 0; /* stdin */
119 else
120 if ((in_fd = open( argv[argptr] , 0)) < 0)
121 exit(-1);
122 argptr++;
123
124 /* output file */
125 if ( !strcmp( argv[argptr], "-" ) )
126 out_fd = 1; /* stdout */
127 else
128 if ((out_fd = creat( argv[argptr] , 0755)) < 0)
129 exit(-1);
130 argptr++;
131
132 /* skip elf header in input file */
133 /*if ( !prep )*/
134 lseek(in_fd, elfhdr_size, SEEK_SET);
135
136 /* write prep partition if necessary */
137 if ( prep )
138 write_prep_partition( in_fd, out_fd );
139
140 /* write input image to bootimage */
141 if ( asmoutput )
142 write_asm_data( in_fd, out_fd );
143 else
144 copy_image(in_fd, out_fd);
145
146 return 0;
147}
148
149void write_prep_partition(int in, int out)
150{
151 unsigned char block[512];
152 partition_entry_t pe;
153 dword_t *entry = (dword_t *)&block[0];
154 dword_t *length = (dword_t *)&block[sizeof(long)];
155 struct stat info;
156
157 if (fstat(in, &info) < 0)
158 {
159 fprintf(stderr,"info failed\n");
160 exit(-1);
161 }
162
163 bzero( block, sizeof block );
164
165 /* set entry point and boot image size skipping over elf header */
166#ifdef __i386__
167 *entry = 0x400/*+65536*/;
168 *length = info.st_size-elfhdr_size+0x400;
169#else
170 *entry = cpu_to_le32(0x400/*+65536*/);
171 *length = cpu_to_le32(info.st_size-elfhdr_size+0x400);
172#endif /* __i386__ */
173
174 /* sets magic number for msdos partition (used by linux) */
175 block[510] = 0x55;
176 block[511] = 0xAA;
177
178 /*
179 * Build a "PReP" partition table entry in the boot record
180 * - "PReP" may only look at the system_indicator
181 */
182 pe.boot_indicator = BootActive;
183 pe.system_indicator = SystemPrep;
184 /*
185 * The first block of the diskette is used by this "boot record" which
186 * actually contains the partition table. (The first block of the
187 * partition contains the boot image, but I digress...) We'll set up
188 * one partition on the diskette and it shall contain the rest of the
189 * diskette.
190 */
191 pe.starting_head = 0; /* zero-based */
192 pe.starting_sector = 2; /* one-based */
193 pe.starting_cylinder = 0; /* zero-based */
194 pe.ending_head = 1; /* assumes two heads */
195 pe.ending_sector = 18; /* assumes 18 sectors/track */
196 pe.ending_cylinder = 79; /* assumes 80 cylinders/diskette */
197
198 /*
199 * The "PReP" software ignores the above fields and just looks at
200 * the next two.
201 * - size of the diskette is (assumed to be)
202 * (2 tracks/cylinder)(18 sectors/tracks)(80 cylinders/diskette)
203 * - unlike the above sector numbers, the beginning sector is zero-based!
204 */
205#if 0
206 pe.beginning_sector = cpu_to_le32(1);
207#else
208 /* This has to be 0 on the PowerStack? */
209#ifdef __i386__
210 pe.beginning_sector = 0;
211#else
212 pe.beginning_sector = cpu_to_le32(0);
213#endif /* __i386__ */
214#endif
215
216#ifdef __i386__
217 pe.number_of_sectors = 2*18*80-1;
218#else
219 pe.number_of_sectors = cpu_to_le32(2*18*80-1);
220#endif /* __i386__ */
221
222 memcpy(&block[0x1BE], &pe, sizeof(pe));
223
224 write( out, block, sizeof(block) );
225 write( out, entry, sizeof(*entry) );
226 write( out, length, sizeof(*length) );
227 /* set file position to 2nd sector where image will be written */
228 lseek( out, 0x400, SEEK_SET );
229}
230
231
232
233void
234copy_image(int in, int out)
235{
236 char buf[SIZE];
237 int n;
238
239 while ( (n = read(in, buf, SIZE)) > 0 )
240 write(out, buf, n);
241}
242
243
244void
245write_asm_data( int in, int out )
246{
247 int i, cnt, pos, len;
248 unsigned int cksum, val;
249 unsigned char *lp;
250 unsigned char buf[SIZE];
251 unsigned char str[256];
252
253 write( out, "\t.data\n\t.globl input_data\ninput_data:\n",
254 strlen( "\t.data\n\t.globl input_data\ninput_data:\n" ) );
255 pos = 0;
256 cksum = 0;
257 while ((len = read(in, buf, sizeof(buf))) > 0)
258 {
259 cnt = 0;
260 lp = (unsigned char *)buf;
261 len = (len + 3) & ~3; /* Round up to longwords */
262 for (i = 0; i < len; i += 4)
263 {
264 if (cnt == 0)
265 {
266 write( out, "\t.long\t", strlen( "\t.long\t" ) );
267 }
268 sprintf( str, "0x%02X%02X%02X%02X", lp[0], lp[1], lp[2], lp[3]);
269 write( out, str, strlen(str) );
270 val = *(unsigned long *)lp;
271 cksum ^= val;
272 lp += 4;
273 if (++cnt == 4)
274 {
275 cnt = 0;
276 sprintf( str, " # %x \n", pos+i-12);
277 write( out, str, strlen(str) );
278 } else
279 {
280 write( out, ",", 1 );
281 }
282 }
283 if (cnt)
284 {
285 write( out, "0\n", 2 );
286 }
287 pos += len;
288 }
289 sprintf(str, "\t.globl input_len\ninput_len:\t.long\t0x%x\n", pos);
290 write( out, str, strlen(str) );
291
292 fprintf(stderr, "cksum = %x\n", cksum);
293}