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 <unistd.h> 33 #include <fcntl.h> 34 #include <sys/mman.h> 35 #include <tools/le_byteshift.h> 36 37 typedef unsigned char u8; 38 typedef unsigned short u16; 39 typedef unsigned int u32; 40 41 #define DEFAULT_MAJOR_ROOT 0 42 #define DEFAULT_MINOR_ROOT 0 43 #define DEFAULT_ROOT_DEV (DEFAULT_MAJOR_ROOT << 8 | DEFAULT_MINOR_ROOT) 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 #define PECOFF_RELOC_RESERVE 0x20 54 55 /*----------------------------------------------------------------------*/ 56 57 static const u32 crctab32[] = { 58 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 59 0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 60 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 61 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 62 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856, 63 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 64 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 65 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 66 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 67 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a, 68 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 69 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 70 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 71 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 72 0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e, 73 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, 74 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 75 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, 76 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 77 0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 78 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 79 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 80 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010, 81 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, 82 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 83 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 84 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 85 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 86 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344, 87 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 88 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 89 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 90 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 91 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c, 92 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 93 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 94 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 95 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 96 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c, 97 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, 98 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 99 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, 100 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 101 0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 102 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278, 103 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 104 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66, 105 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, 106 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 107 0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 108 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 109 0x2d02ef8d 110 }; 111 112 static u32 partial_crc32_one(u8 c, u32 crc) 113 { 114 return crctab32[(crc ^ c) & 0xff] ^ (crc >> 8); 115 } 116 117 static u32 partial_crc32(const u8 *s, int len, u32 crc) 118 { 119 while (len--) 120 crc = partial_crc32_one(*s++, crc); 121 return crc; 122 } 123 124 static void die(const char * str, ...) 125 { 126 va_list args; 127 va_start(args, str); 128 vfprintf(stderr, str, args); 129 fputc('\n', stderr); 130 exit(1); 131 } 132 133 static void usage(void) 134 { 135 die("Usage: build setup system [> image]"); 136 } 137 138 #ifdef CONFIG_EFI_STUB 139 140 static void update_pecoff_section_header(char *section_name, u32 offset, u32 size) 141 { 142 unsigned int pe_header; 143 unsigned short num_sections; 144 u8 *section; 145 146 pe_header = get_unaligned_le32(&buf[0x3c]); 147 num_sections = get_unaligned_le16(&buf[pe_header + 6]); 148 149 #ifdef CONFIG_X86_32 150 section = &buf[pe_header + 0xa8]; 151 #else 152 section = &buf[pe_header + 0xb8]; 153 #endif 154 155 while (num_sections > 0) { 156 if (strncmp((char*)section, section_name, 8) == 0) { 157 /* section header size field */ 158 put_unaligned_le32(size, section + 0x8); 159 160 /* section header vma field */ 161 put_unaligned_le32(offset, section + 0xc); 162 163 /* section header 'size of initialised data' field */ 164 put_unaligned_le32(size, section + 0x10); 165 166 /* section header 'file offset' field */ 167 put_unaligned_le32(offset, section + 0x14); 168 169 break; 170 } 171 section += 0x28; 172 num_sections--; 173 } 174 } 175 176 static void update_pecoff_setup_and_reloc(unsigned int size) 177 { 178 u32 setup_offset = 0x200; 179 u32 reloc_offset = size - PECOFF_RELOC_RESERVE; 180 u32 setup_size = reloc_offset - setup_offset; 181 182 update_pecoff_section_header(".setup", setup_offset, setup_size); 183 update_pecoff_section_header(".reloc", reloc_offset, PECOFF_RELOC_RESERVE); 184 185 /* 186 * Modify .reloc section contents with a single entry. The 187 * relocation is applied to offset 10 of the relocation section. 188 */ 189 put_unaligned_le32(reloc_offset + 10, &buf[reloc_offset]); 190 put_unaligned_le32(10, &buf[reloc_offset + 4]); 191 } 192 193 static void update_pecoff_text(unsigned int text_start, unsigned int file_sz) 194 { 195 unsigned int pe_header; 196 unsigned int text_sz = file_sz - text_start; 197 198 pe_header = get_unaligned_le32(&buf[0x3c]); 199 200 /* Size of image */ 201 put_unaligned_le32(file_sz, &buf[pe_header + 0x50]); 202 203 /* 204 * Size of code: Subtract the size of the first sector (512 bytes) 205 * which includes the header. 206 */ 207 put_unaligned_le32(file_sz - 512, &buf[pe_header + 0x1c]); 208 209 #ifdef CONFIG_X86_32 210 /* 211 * Address of entry point. 212 * 213 * The EFI stub entry point is +16 bytes from the start of 214 * the .text section. 215 */ 216 put_unaligned_le32(text_start + 16, &buf[pe_header + 0x28]); 217 #else 218 /* 219 * Address of entry point. startup_32 is at the beginning and 220 * the 64-bit entry point (startup_64) is always 512 bytes 221 * after. The EFI stub entry point is 16 bytes after that, as 222 * the first instruction allows legacy loaders to jump over 223 * the EFI stub initialisation 224 */ 225 put_unaligned_le32(text_start + 528, &buf[pe_header + 0x28]); 226 #endif /* CONFIG_X86_32 */ 227 228 update_pecoff_section_header(".text", text_start, text_sz); 229 } 230 231 #endif /* CONFIG_EFI_STUB */ 232 233 int main(int argc, char ** argv) 234 { 235 unsigned int i, sz, setup_sectors; 236 int c; 237 u32 sys_size; 238 struct stat sb; 239 FILE *file; 240 int fd; 241 void *kernel; 242 u32 crc = 0xffffffffUL; 243 244 if (argc != 3) 245 usage(); 246 247 /* Copy the setup code */ 248 file = fopen(argv[1], "r"); 249 if (!file) 250 die("Unable to open `%s': %m", argv[1]); 251 c = fread(buf, 1, sizeof(buf), file); 252 if (ferror(file)) 253 die("read-error on `setup'"); 254 if (c < 1024) 255 die("The setup must be at least 1024 bytes"); 256 if (get_unaligned_le16(&buf[510]) != 0xAA55) 257 die("Boot block hasn't got boot flag (0xAA55)"); 258 fclose(file); 259 260 #ifdef CONFIG_EFI_STUB 261 /* Reserve 0x20 bytes for .reloc section */ 262 memset(buf+c, 0, PECOFF_RELOC_RESERVE); 263 c += PECOFF_RELOC_RESERVE; 264 #endif 265 266 /* Pad unused space with zeros */ 267 setup_sectors = (c + 511) / 512; 268 if (setup_sectors < SETUP_SECT_MIN) 269 setup_sectors = SETUP_SECT_MIN; 270 i = setup_sectors*512; 271 memset(buf+c, 0, i-c); 272 273 #ifdef CONFIG_EFI_STUB 274 update_pecoff_setup_and_reloc(i); 275 #endif 276 277 /* Set the default root device */ 278 put_unaligned_le16(DEFAULT_ROOT_DEV, &buf[508]); 279 280 fprintf(stderr, "Setup is %d bytes (padded to %d bytes).\n", c, i); 281 282 /* Open and stat the kernel file */ 283 fd = open(argv[2], O_RDONLY); 284 if (fd < 0) 285 die("Unable to open `%s': %m", argv[2]); 286 if (fstat(fd, &sb)) 287 die("Unable to stat `%s': %m", argv[2]); 288 sz = sb.st_size; 289 fprintf (stderr, "System is %d kB\n", (sz+1023)/1024); 290 kernel = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0); 291 if (kernel == MAP_FAILED) 292 die("Unable to mmap '%s': %m", argv[2]); 293 /* Number of 16-byte paragraphs, including space for a 4-byte CRC */ 294 sys_size = (sz + 15 + 4) / 16; 295 296 /* Patch the setup code with the appropriate size parameters */ 297 buf[0x1f1] = setup_sectors-1; 298 put_unaligned_le32(sys_size, &buf[0x1f4]); 299 300 #ifdef CONFIG_EFI_STUB 301 update_pecoff_text(setup_sectors * 512, sz + i + ((sys_size * 16) - sz)); 302 #endif 303 304 crc = partial_crc32(buf, i, crc); 305 if (fwrite(buf, 1, i, stdout) != i) 306 die("Writing setup failed"); 307 308 /* Copy the kernel code */ 309 crc = partial_crc32(kernel, sz, crc); 310 if (fwrite(kernel, 1, sz, stdout) != sz) 311 die("Writing kernel failed"); 312 313 /* Add padding leaving 4 bytes for the checksum */ 314 while (sz++ < (sys_size*16) - 4) { 315 crc = partial_crc32_one('\0', crc); 316 if (fwrite("\0", 1, 1, stdout) != 1) 317 die("Writing padding failed"); 318 } 319 320 /* Write the CRC */ 321 fprintf(stderr, "CRC %x\n", crc); 322 put_unaligned_le32(crc, buf); 323 if (fwrite(buf, 1, 4, stdout) != 4) 324 die("Writing CRC failed"); 325 326 close(fd); 327 328 /* Everything is OK */ 329 return 0; 330 } 331