1 /* tools/mkbootimg/mkbootimg.c
2 **
3 ** Copyright 2007, The Android Open Source Project
4 **
5 ** Licensed under the Apache License, Version 2.0 (the "License");
6 ** you may not use this file except in compliance with the License.
7 ** You may obtain a copy of the License at
8 **
9 ** http://www.apache.org/licenses/LICENSE-2.0
10 **
11 ** Unless required by applicable law or agreed to in writing, software
12 ** distributed under the License is distributed on an "AS IS" BASIS,
13 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 ** See the License for the specific language governing permissions and
15 ** limitations under the License.
16 */
17
18 #include <stdio.h>
19 #include <stdlib.h>
20 #include <string.h>
21 #include <unistd.h>
22 #include <fcntl.h>
23 #include <errno.h>
24
25 #include "mincrypt/sha.h"
26 #include "bootimg.h"
27
load_file(const char * fn,unsigned * _sz)28 static void *load_file(const char *fn, unsigned *_sz)
29 {
30 char *data;
31 int sz;
32 int fd;
33
34 data = 0;
35 fd = open(fn, O_RDONLY);
36 if(fd < 0) return 0;
37
38 sz = lseek(fd, 0, SEEK_END);
39 if(sz < 0) goto oops;
40
41 if(lseek(fd, 0, SEEK_SET) != 0) goto oops;
42
43 data = (char*) malloc(sz);
44 if(data == 0) goto oops;
45
46 if(read(fd, data, sz) != sz) goto oops;
47 close(fd);
48
49 if(_sz) *_sz = sz;
50 return data;
51
52 oops:
53 close(fd);
54 if(data != 0) free(data);
55 return 0;
56 }
57
usage(void)58 int usage(void)
59 {
60 fprintf(stderr,"usage: mkbootimg\n"
61 " --kernel <filename>\n"
62 " --ramdisk <filename>\n"
63 " [ --second <2ndbootloader-filename> ]\n"
64 " [ --cmdline <kernel-commandline> ]\n"
65 " [ --board <boardname> ]\n"
66 " [ --base <address> ]\n"
67 " -o|--output <filename>\n"
68 );
69 return 1;
70 }
71
72
73
74 static unsigned char padding[2048] = { 0, };
75
write_padding(int fd,unsigned pagesize,unsigned itemsize)76 int write_padding(int fd, unsigned pagesize, unsigned itemsize)
77 {
78 unsigned pagemask = pagesize - 1;
79 unsigned count;
80
81 if((itemsize & pagemask) == 0) {
82 return 0;
83 }
84
85 count = pagesize - (itemsize & pagemask);
86
87 if(write(fd, padding, count) != count) {
88 return -1;
89 } else {
90 return 0;
91 }
92 }
93
main(int argc,char ** argv)94 int main(int argc, char **argv)
95 {
96 boot_img_hdr hdr;
97
98 char *kernel_fn = 0;
99 void *kernel_data = 0;
100 char *ramdisk_fn = 0;
101 void *ramdisk_data = 0;
102 char *second_fn = 0;
103 void *second_data = 0;
104 char *cmdline = "";
105 char *bootimg = 0;
106 char *board = "";
107 unsigned pagesize = 2048;
108 int fd;
109 SHA_CTX ctx;
110 uint8_t* sha;
111
112 argc--;
113 argv++;
114
115 memset(&hdr, 0, sizeof(hdr));
116
117 /* default load addresses */
118 hdr.kernel_addr = 0x10008000;
119 hdr.ramdisk_addr = 0x11000000;
120 hdr.second_addr = 0x10F00000;
121 hdr.tags_addr = 0x10000100;
122
123 hdr.page_size = pagesize;
124
125 while(argc > 0){
126 char *arg = argv[0];
127 char *val = argv[1];
128 if(argc < 2) {
129 return usage();
130 }
131 argc -= 2;
132 argv += 2;
133 if(!strcmp(arg, "--output") || !strcmp(arg, "-o")) {
134 bootimg = val;
135 } else if(!strcmp(arg, "--kernel")) {
136 kernel_fn = val;
137 } else if(!strcmp(arg, "--ramdisk")) {
138 ramdisk_fn = val;
139 } else if(!strcmp(arg, "--second")) {
140 second_fn = val;
141 } else if(!strcmp(arg, "--cmdline")) {
142 cmdline = val;
143 } else if(!strcmp(arg, "--base")) {
144 unsigned base = strtoul(val, 0, 16);
145 hdr.kernel_addr = base + 0x00008000;
146 hdr.ramdisk_addr = base + 0x01000000;
147 hdr.second_addr = base + 0x00F00000;
148 hdr.tags_addr = base + 0x00000100;
149 } else if(!strcmp(arg, "--board")) {
150 board = val;
151 } else {
152 return usage();
153 }
154 }
155
156 if(bootimg == 0) {
157 fprintf(stderr,"error: no output filename specified\n");
158 return usage();
159 }
160
161 if(kernel_fn == 0) {
162 fprintf(stderr,"error: no kernel image specified\n");
163 return usage();
164 }
165
166 if(ramdisk_fn == 0) {
167 fprintf(stderr,"error: no ramdisk image specified\n");
168 return usage();
169 }
170
171 if(strlen(board) >= BOOT_NAME_SIZE) {
172 fprintf(stderr,"error: board name too large\n");
173 return usage();
174 }
175
176 strcpy(hdr.name, board);
177
178 memcpy(hdr.magic, BOOT_MAGIC, BOOT_MAGIC_SIZE);
179
180 if(strlen(cmdline) > (BOOT_ARGS_SIZE - 1)) {
181 fprintf(stderr,"error: kernel commandline too large\n");
182 return 1;
183 }
184 strcpy((char*)hdr.cmdline, cmdline);
185
186 kernel_data = load_file(kernel_fn, &hdr.kernel_size);
187 if(kernel_data == 0) {
188 fprintf(stderr,"error: could not load kernel '%s'\n", kernel_fn);
189 return 1;
190 }
191
192 if(!strcmp(ramdisk_fn,"NONE")) {
193 ramdisk_data = 0;
194 hdr.ramdisk_size = 0;
195 } else {
196 ramdisk_data = load_file(ramdisk_fn, &hdr.ramdisk_size);
197 if(ramdisk_data == 0) {
198 fprintf(stderr,"error: could not load ramdisk '%s'\n", ramdisk_fn);
199 return 1;
200 }
201 }
202
203 if(second_fn) {
204 second_data = load_file(second_fn, &hdr.second_size);
205 if(second_data == 0) {
206 fprintf(stderr,"error: could not load secondstage '%s'\n", second_fn);
207 return 1;
208 }
209 }
210
211 /* put a hash of the contents in the header so boot images can be
212 * differentiated based on their first 2k.
213 */
214 SHA_init(&ctx);
215 SHA_update(&ctx, kernel_data, hdr.kernel_size);
216 SHA_update(&ctx, &hdr.kernel_size, sizeof(hdr.kernel_size));
217 SHA_update(&ctx, ramdisk_data, hdr.ramdisk_size);
218 SHA_update(&ctx, &hdr.ramdisk_size, sizeof(hdr.ramdisk_size));
219 SHA_update(&ctx, second_data, hdr.second_size);
220 SHA_update(&ctx, &hdr.second_size, sizeof(hdr.second_size));
221 sha = SHA_final(&ctx);
222 memcpy(hdr.id, sha,
223 SHA_DIGEST_SIZE > sizeof(hdr.id) ? sizeof(hdr.id) : SHA_DIGEST_SIZE);
224
225 fd = open(bootimg, O_CREAT | O_TRUNC | O_WRONLY, 0644);
226 if(fd < 0) {
227 fprintf(stderr,"error: could not create '%s'\n", bootimg);
228 return 1;
229 }
230
231 if(write(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) goto fail;
232 if(write_padding(fd, pagesize, sizeof(hdr))) goto fail;
233
234 if(write(fd, kernel_data, hdr.kernel_size) != hdr.kernel_size) goto fail;
235 if(write_padding(fd, pagesize, hdr.kernel_size)) goto fail;
236
237 if(write(fd, ramdisk_data, hdr.ramdisk_size) != hdr.ramdisk_size) goto fail;
238 if(write_padding(fd, pagesize, hdr.ramdisk_size)) goto fail;
239
240 if(second_data) {
241 if(write(fd, second_data, hdr.second_size) != hdr.second_size) goto fail;
242 if(write_padding(fd, pagesize, hdr.ramdisk_size)) goto fail;
243 }
244
245 return 0;
246
247 fail:
248 unlink(bootimg);
249 close(fd);
250 fprintf(stderr,"error: failed writing '%s': %s\n", bootimg,
251 strerror(errno));
252 return 1;
253 }
254