1 /* 2 * Copyright (C) 1991, 1992 Linus Torvalds 3 * Copyright (C) 1997 Martin Mares 4 * Copyright (C) 2007 H. Peter Anvin 5 */ 6 7 /* 8 * This file builds a disk-image from two different files: 9 * 10 * - setup: 8086 machine code, sets up system parm 11 * - system: 80386 code for actual system 12 * 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. 16 */ 17 18 /* 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 24 */ 25 26 #include <stdio.h> 27 #include <string.h> 28 #include <stdlib.h> 29 #include <stdarg.h> 30 #include <sys/types.h> 31 #include <sys/stat.h> 32 #include <sys/sysmacros.h> 33 #include <unistd.h> 34 #include <fcntl.h> 35 #include <sys/mman.h> 36 #include <asm/boot.h> 37 38 typedef unsigned char u8; 39 typedef unsigned short u16; 40 typedef unsigned long u32; 41 42 #define DEFAULT_MAJOR_ROOT 0 43 #define DEFAULT_MINOR_ROOT 0 44 45 /* Minimal number of setup sectors */ 46 #define SETUP_SECT_MIN 5 47 #define SETUP_SECT_MAX 64 48 49 /* This must be large enough to hold the entire setup */ 50 u8 buf[SETUP_SECT_MAX*512]; 51 int is_big_kernel; 52 53 /*----------------------------------------------------------------------*/ 54 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, 107 0x2d02ef8d 108 }; 109 110 static u32 partial_crc32_one(u8 c, u32 crc) 111 { 112 return crctab32[(crc ^ c) & 0xff] ^ (crc >> 8); 113 } 114 115 static u32 partial_crc32(const u8 *s, int len, u32 crc) 116 { 117 while (len--) 118 crc = partial_crc32_one(*s++, crc); 119 return crc; 120 } 121 122 static void die(const char * str, ...) 123 { 124 va_list args; 125 va_start(args, str); 126 vfprintf(stderr, str, args); 127 fputc('\n', stderr); 128 exit(1); 129 } 130 131 static void usage(void) 132 { 133 die("Usage: build setup system [> image]"); 134 } 135 136 int main(int argc, char ** argv) 137 { 138 #ifdef CONFIG_EFI_STUB 139 unsigned int file_sz, pe_header; 140 #endif 141 unsigned int i, sz, setup_sectors; 142 int c; 143 u32 sys_size; 144 struct stat sb; 145 FILE *file; 146 int fd; 147 void *kernel; 148 u32 crc = 0xffffffffUL; 149 150 if (argc != 3) 151 usage(); 152 153 /* Copy the setup code */ 154 file = fopen(argv[1], "r"); 155 if (!file) 156 die("Unable to open `%s': %m", argv[1]); 157 c = fread(buf, 1, sizeof(buf), file); 158 if (ferror(file)) 159 die("read-error on `setup'"); 160 if (c < 1024) 161 die("The setup must be at least 1024 bytes"); 162 if (buf[510] != 0x55 || buf[511] != 0xaa) 163 die("Boot block hasn't got boot flag (0xAA55)"); 164 fclose(file); 165 166 /* 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); 172 173 /* Set the default root device */ 174 buf[508] = DEFAULT_MINOR_ROOT; 175 buf[509] = DEFAULT_MAJOR_ROOT; 176 177 fprintf(stderr, "Setup is %d bytes (padded to %d bytes).\n", c, i); 178 179 /* Open and stat the kernel file */ 180 fd = open(argv[2], O_RDONLY); 181 if (fd < 0) 182 die("Unable to open `%s': %m", argv[2]); 183 if (fstat(fd, &sb)) 184 die("Unable to stat `%s': %m", argv[2]); 185 sz = sb.st_size; 186 fprintf (stderr, "System is %d kB\n", (sz+1023)/1024); 187 kernel = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0); 188 if (kernel == MAP_FAILED) 189 die("Unable to mmap '%s': %m", argv[2]); 190 /* Number of 16-byte paragraphs, including space for a 4-byte CRC */ 191 sys_size = (sz + 15 + 4) / 16; 192 193 /* Patch the setup code with the appropriate size parameters */ 194 buf[0x1f1] = setup_sectors-1; 195 buf[0x1f4] = sys_size; 196 buf[0x1f5] = sys_size >> 8; 197 buf[0x1f6] = sys_size >> 16; 198 buf[0x1f7] = sys_size >> 24; 199 200 #ifdef CONFIG_EFI_STUB 201 file_sz = sz + i + ((sys_size * 16) - sz); 202 203 pe_header = *(unsigned int *)&buf[0x3c]; 204 205 /* Size of code */ 206 *(unsigned int *)&buf[pe_header + 0x1c] = file_sz; 207 208 /* Size of image */ 209 *(unsigned int *)&buf[pe_header + 0x50] = file_sz; 210 211 #ifdef CONFIG_X86_32 212 /* Address of entry point */ 213 *(unsigned int *)&buf[pe_header + 0x28] = i; 214 215 /* .text size */ 216 *(unsigned int *)&buf[pe_header + 0xb0] = file_sz; 217 218 /* .text size of initialised data */ 219 *(unsigned int *)&buf[pe_header + 0xb8] = file_sz; 220 #else 221 /* 222 * Address of entry point. startup_32 is at the beginning and 223 * the 64-bit entry point (startup_64) is always 512 bytes 224 * after. 225 */ 226 *(unsigned int *)&buf[pe_header + 0x28] = i + 512; 227 228 /* .text size */ 229 *(unsigned int *)&buf[pe_header + 0xc0] = file_sz; 230 231 /* .text size of initialised data */ 232 *(unsigned int *)&buf[pe_header + 0xc8] = file_sz; 233 #endif /* CONFIG_X86_32 */ 234 #endif /* CONFIG_EFI_STUB */ 235 236 crc = partial_crc32(buf, i, crc); 237 if (fwrite(buf, 1, i, stdout) != i) 238 die("Writing setup failed"); 239 240 /* Copy the kernel code */ 241 crc = partial_crc32(kernel, sz, crc); 242 if (fwrite(kernel, 1, sz, stdout) != sz) 243 die("Writing kernel failed"); 244 245 /* Add padding leaving 4 bytes for the checksum */ 246 while (sz++ < (sys_size*16) - 4) { 247 crc = partial_crc32_one('\0', crc); 248 if (fwrite("\0", 1, 1, stdout) != 1) 249 die("Writing padding failed"); 250 } 251 252 /* Write the CRC */ 253 fprintf(stderr, "CRC %lx\n", crc); 254 if (fwrite(&crc, 1, 4, stdout) != 4) 255 die("Writing CRC failed"); 256 257 close(fd); 258 259 /* Everything is OK */ 260 return 0; 261 } 262