2 * Copyright (C) 1991, 1992 Linus Torvalds
3 * Copyright (C) 1997 Martin Mares
4 * Copyright (C) 2007 H. Peter Anvin
8 * This file builds a disk-image from two different files:
10 * - setup: 8086 machine code, sets up system parm
11 * - system: 80386 code for actual system
13 * It does some checking that all files are of the correct type, and
14 * just writes the result to stdout, removing headers and padding to
15 * the right amount. It also writes some system data to stderr.
19 * Changes by tytso to allow root device specification
20 * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
21 * Cross compiling fixes by Gertjan van Wingerde, July 1996
22 * Rewritten by Martin Mares, April 1997
23 * Substantially overhauled by H. Peter Anvin, April 2007
30 #include <sys/types.h>
35 #include <tools/le_byteshift.h>
37 typedef unsigned char u8;
38 typedef unsigned short u16;
39 typedef unsigned int u32;
41 #define DEFAULT_MAJOR_ROOT 0
42 #define DEFAULT_MINOR_ROOT 0
43 #define DEFAULT_ROOT_DEV (DEFAULT_MAJOR_ROOT << 8 | DEFAULT_MINOR_ROOT)
45 /* Minimal number of setup sectors */
46 #define SETUP_SECT_MIN 5
47 #define SETUP_SECT_MAX 64
49 /* This must be large enough to hold the entire setup */
50 u8 buf[SETUP_SECT_MAX*512];
53 /*----------------------------------------------------------------------*/
55 static const u32 crctab32[] = {
56 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419,
57 0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4,
58 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07,
59 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
60 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856,
61 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
62 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4,
63 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
64 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3,
65 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a,
66 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599,
67 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
68 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190,
69 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f,
70 0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e,
71 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
72 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed,
73 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
74 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3,
75 0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
76 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a,
77 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5,
78 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010,
79 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
80 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17,
81 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6,
82 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615,
83 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
84 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344,
85 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
86 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a,
87 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
88 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1,
89 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c,
90 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef,
91 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
92 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe,
93 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31,
94 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c,
95 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
96 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b,
97 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
98 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1,
99 0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
100 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278,
101 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7,
102 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66,
103 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
104 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605,
105 0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8,
106 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b,
110 static u32 partial_crc32_one(u8 c, u32 crc)
112 return crctab32[(crc ^ c) & 0xff] ^ (crc >> 8);
115 static u32 partial_crc32(const u8 *s, int len, u32 crc)
118 crc = partial_crc32_one(*s++, crc);
122 static void die(const char * str, ...)
126 vfprintf(stderr, str, args);
131 static void usage(void)
133 die("Usage: build setup system [> image]");
136 int main(int argc, char ** argv)
138 #ifdef CONFIG_EFI_STUB
139 unsigned int file_sz, pe_header;
141 unsigned int i, sz, setup_sectors;
148 u32 crc = 0xffffffffUL;
153 /* Copy the setup code */
154 file = fopen(argv[1], "r");
156 die("Unable to open `%s': %m", argv[1]);
157 c = fread(buf, 1, sizeof(buf), file);
159 die("read-error on `setup'");
161 die("The setup must be at least 1024 bytes");
162 if (get_unaligned_le16(&buf[510]) != 0xAA55)
163 die("Boot block hasn't got boot flag (0xAA55)");
166 /* Pad unused space with zeros */
167 setup_sectors = (c + 511) / 512;
168 if (setup_sectors < SETUP_SECT_MIN)
169 setup_sectors = SETUP_SECT_MIN;
170 i = setup_sectors*512;
171 memset(buf+c, 0, i-c);
173 /* Set the default root device */
174 put_unaligned_le16(DEFAULT_ROOT_DEV, &buf[508]);
176 fprintf(stderr, "Setup is %d bytes (padded to %d bytes).\n", c, i);
178 /* Open and stat the kernel file */
179 fd = open(argv[2], O_RDONLY);
181 die("Unable to open `%s': %m", argv[2]);
183 die("Unable to stat `%s': %m", argv[2]);
185 fprintf (stderr, "System is %d kB\n", (sz+1023)/1024);
186 kernel = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0);
187 if (kernel == MAP_FAILED)
188 die("Unable to mmap '%s': %m", argv[2]);
189 /* Number of 16-byte paragraphs, including space for a 4-byte CRC */
190 sys_size = (sz + 15 + 4) / 16;
192 /* Patch the setup code with the appropriate size parameters */
193 buf[0x1f1] = setup_sectors-1;
194 put_unaligned_le32(sys_size, &buf[0x1f4]);
196 #ifdef CONFIG_EFI_STUB
197 file_sz = sz + i + ((sys_size * 16) - sz);
199 pe_header = get_unaligned_le32(&buf[0x3c]);
202 put_unaligned_le32(file_sz, &buf[pe_header + 0x50]);
205 * Subtract the size of the first section (512 bytes) which
206 * includes the header and .reloc section. The remaining size
207 * is that of the .text section.
212 put_unaligned_le32(file_sz, &buf[pe_header + 0x1c]);
216 * Address of entry point.
218 * The EFI stub entry point is +16 bytes from the start of
221 put_unaligned_le32(i + 16, &buf[pe_header + 0x28]);
224 put_unaligned_le32(file_sz, &buf[pe_header + 0xb0]);
227 put_unaligned_le32(0x200, &buf[pe_header + 0xb4]);
229 /* .text size of initialised data */
230 put_unaligned_le32(file_sz, &buf[pe_header + 0xb8]);
232 /* .text file offset */
233 put_unaligned_le32(0x200, &buf[pe_header + 0xbc]);
236 * Address of entry point. startup_32 is at the beginning and
237 * the 64-bit entry point (startup_64) is always 512 bytes
238 * after. The EFI stub entry point is 16 bytes after that, as
239 * the first instruction allows legacy loaders to jump over
240 * the EFI stub initialisation
242 put_unaligned_le32(i + 528, &buf[pe_header + 0x28]);
245 put_unaligned_le32(file_sz, &buf[pe_header + 0xc0]);
248 put_unaligned_le32(0x200, &buf[pe_header + 0xc4]);
250 /* .text size of initialised data */
251 put_unaligned_le32(file_sz, &buf[pe_header + 0xc8]);
253 /* .text file offset */
254 put_unaligned_le32(0x200, &buf[pe_header + 0xcc]);
255 #endif /* CONFIG_X86_32 */
256 #endif /* CONFIG_EFI_STUB */
258 crc = partial_crc32(buf, i, crc);
259 if (fwrite(buf, 1, i, stdout) != i)
260 die("Writing setup failed");
262 /* Copy the kernel code */
263 crc = partial_crc32(kernel, sz, crc);
264 if (fwrite(kernel, 1, sz, stdout) != sz)
265 die("Writing kernel failed");
267 /* Add padding leaving 4 bytes for the checksum */
268 while (sz++ < (sys_size*16) - 4) {
269 crc = partial_crc32_one('\0', crc);
270 if (fwrite("\0", 1, 1, stdout) != 1)
271 die("Writing padding failed");
275 fprintf(stderr, "CRC %x\n", crc);
276 put_unaligned_le32(crc, buf);
277 if (fwrite(buf, 1, 4, stdout) != 4)
278 die("Writing CRC failed");
282 /* Everything is OK */