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 /*----------------------------------------------------------------------*/
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
partial_crc32_one(u8 c,u32 crc)110 static u32 partial_crc32_one(u8 c, u32 crc)
111 {
112 return crctab32[(crc ^ c) & 0xff] ^ (crc >> 8);
113 }
114
partial_crc32(const u8 * s,int len,u32 crc)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
die(const char * str,...)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
usage(void)131 static void usage(void)
132 {
133 die("Usage: build setup system [> image]");
134 }
135
main(int argc,char ** argv)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 (get_unaligned_le16(&buf[510]) != 0xAA55)
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 put_unaligned_le16(DEFAULT_ROOT_DEV, &buf[508]);
175
176 fprintf(stderr, "Setup is %d bytes (padded to %d bytes).\n", c, i);
177
178 /* Open and stat the kernel file */
179 fd = open(argv[2], O_RDONLY);
180 if (fd < 0)
181 die("Unable to open `%s': %m", argv[2]);
182 if (fstat(fd, &sb))
183 die("Unable to stat `%s': %m", argv[2]);
184 sz = sb.st_size;
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;
191
192 /* Patch the setup code with the appropriate size parameters */
193 buf[0x1f1] = setup_sectors-1;
194 put_unaligned_le32(sys_size, &buf[0x1f4]);
195
196 #ifdef CONFIG_EFI_STUB
197 file_sz = sz + i + ((sys_size * 16) - sz);
198
199 pe_header = get_unaligned_le32(&buf[0x3c]);
200
201 /* Size of code */
202 put_unaligned_le32(file_sz, &buf[pe_header + 0x1c]);
203
204 /* Size of image */
205 put_unaligned_le32(file_sz, &buf[pe_header + 0x50]);
206
207 #ifdef CONFIG_X86_32
208 /*
209 * Address of entry point.
210 *
211 * The EFI stub entry point is +16 bytes from the start of
212 * the .text section.
213 */
214 put_unaligned_le32(i + 16, &buf[pe_header + 0x28]);
215
216 /* .text size */
217 put_unaligned_le32(file_sz, &buf[pe_header + 0xb0]);
218
219 /* .text size of initialised data */
220 put_unaligned_le32(file_sz, &buf[pe_header + 0xb8]);
221 #else
222 /*
223 * Address of entry point. startup_32 is at the beginning and
224 * the 64-bit entry point (startup_64) is always 512 bytes
225 * after. The EFI stub entry point is 16 bytes after that, as
226 * the first instruction allows legacy loaders to jump over
227 * the EFI stub initialisation
228 */
229 put_unaligned_le32(i + 528, &buf[pe_header + 0x28]);
230
231 /* .text size */
232 put_unaligned_le32(file_sz, &buf[pe_header + 0xc0]);
233
234 /* .text size of initialised data */
235 put_unaligned_le32(file_sz, &buf[pe_header + 0xc8]);
236
237 #endif /* CONFIG_X86_32 */
238 #endif /* CONFIG_EFI_STUB */
239
240 crc = partial_crc32(buf, i, crc);
241 if (fwrite(buf, 1, i, stdout) != i)
242 die("Writing setup failed");
243
244 /* Copy the kernel code */
245 crc = partial_crc32(kernel, sz, crc);
246 if (fwrite(kernel, 1, sz, stdout) != sz)
247 die("Writing kernel failed");
248
249 /* Add padding leaving 4 bytes for the checksum */
250 while (sz++ < (sys_size*16) - 4) {
251 crc = partial_crc32_one('\0', crc);
252 if (fwrite("\0", 1, 1, stdout) != 1)
253 die("Writing padding failed");
254 }
255
256 /* Write the CRC */
257 fprintf(stderr, "CRC %x\n", crc);
258 put_unaligned_le32(crc, buf);
259 if (fwrite(buf, 1, 4, stdout) != 4)
260 die("Writing CRC failed");
261
262 close(fd);
263
264 /* Everything is OK */
265 return 0;
266 }
267