mkbootimg.c revision 8ac3a138168f79b47356fb5aea2f6d95fc3147c6 
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
28static 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
52oops:
53    close(fd);
54    if(data != 0) free(data);
55    return 0;
56}
57
58int 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            "       -o|--output <filename>\n"
67            );
68    return 1;
69}
70
71
72
73static unsigned char padding[2048] = { 0, };
74
75int write_padding(int fd, unsigned pagesize, unsigned itemsize)
76{
77    unsigned pagemask = pagesize - 1;
78    unsigned count;
79
80    if((itemsize & pagemask) == 0) {
81        return 0;
82    }
83
84    count = pagesize - (itemsize & pagemask);
85
86    if(write(fd, padding, count) != count) {
87        return -1;
88    } else {
89        return 0;
90    }
91}
92
93int main(int argc, char **argv)
94{
95    boot_img_hdr hdr;
96
97    char *kernel_fn = 0;
98    void *kernel_data = 0;
99    char *ramdisk_fn = 0;
100    void *ramdisk_data = 0;
101    char *second_fn = 0;
102    void *second_data = 0;
103    char *cmdline = "";
104    char *bootimg = 0;
105    char *board = "";
106    unsigned pagesize = 2048;
107    unsigned saddr = 0;
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    while(argc > 0){
118        char *arg = argv[0];
119        char *val = argv[1];
120        if(argc < 2) {
121            return usage();
122        }
123        argc -= 2;
124        argv += 2;
125        if(!strcmp(arg, "--output") || !strcmp(arg, "-o")) {
126            bootimg = val;
127        } else if(!strcmp(arg, "--kernel")) {
128            kernel_fn = val;
129        } else if(!strcmp(arg, "--ramdisk")) {
130            ramdisk_fn = val;
131        } else if(!strcmp(arg, "--second")) {
132            second_fn = val;
133        } else if(!strcmp(arg, "--cmdline")) {
134            cmdline = val;
135        } else if(!strcmp(arg, "--saddr")) {
136            saddr = strtoul(val, 0, 16);
137        } else if(!strcmp(arg, "--board")) {
138            board = val;
139        } else {
140            return usage();
141        }
142    }
143
144    if(bootimg == 0) {
145        fprintf(stderr,"error: no output filename specified\n");
146        return usage();
147    }
148
149    if(kernel_fn == 0) {
150        fprintf(stderr,"error: no kernel image specified\n");
151        return usage();
152    }
153
154    if(ramdisk_fn == 0) {
155        fprintf(stderr,"error: no ramdisk image specified\n");
156        return usage();
157    }
158
159    if(strlen(board) >= BOOT_NAME_SIZE) {
160        fprintf(stderr,"error: board name too large\n");
161        return usage();
162    }
163
164    strcpy(hdr.name, board);
165
166    hdr.kernel_addr =  0x10008000;
167    hdr.ramdisk_addr = 0x11000000;
168    if(saddr) {
169        hdr.second_addr =  0x00300000;
170    } else {
171        hdr.second_addr =  0x10F00000;
172    }
173    hdr.tags_addr   =  0x10000100;
174    hdr.page_size = pagesize;
175
176    memcpy(hdr.magic, BOOT_MAGIC, BOOT_MAGIC_SIZE);
177
178    if(strlen(cmdline) > (BOOT_ARGS_SIZE - 1)) {
179        fprintf(stderr,"error: kernel commandline too large\n");
180        return 1;
181    }
182    strcpy((char*)hdr.cmdline, cmdline);
183
184    kernel_data = load_file(kernel_fn, &hdr.kernel_size);
185    if(kernel_data == 0) {
186        fprintf(stderr,"error: could not load kernel '%s'\n", kernel_fn);
187        return 1;
188    }
189
190    if(!strcmp(ramdisk_fn,"NONE")) {
191        ramdisk_data = 0;
192        hdr.ramdisk_size = 0;
193    } else {
194        ramdisk_data = load_file(ramdisk_fn, &hdr.ramdisk_size);
195        if(ramdisk_data == 0) {
196            fprintf(stderr,"error: could not load ramdisk '%s'\n", ramdisk_fn);
197            return 1;
198        }
199    }
200
201    if(second_fn) {
202        second_data = load_file(second_fn, &hdr.second_size);
203        if(second_data == 0) {
204            fprintf(stderr,"error: could not load secondstage '%s'\n", second_fn);
205            return 1;
206        }
207    }
208
209    /* put a hash of the contents in the header so boot images can be
210     * differentiated based on their first 2k.
211     */
212    SHA_init(&ctx);
213    SHA_update(&ctx, kernel_data, hdr.kernel_size);
214    SHA_update(&ctx, &hdr.kernel_size, sizeof(hdr.kernel_size));
215    SHA_update(&ctx, ramdisk_data, hdr.ramdisk_size);
216    SHA_update(&ctx, &hdr.ramdisk_size, sizeof(hdr.ramdisk_size));
217    SHA_update(&ctx, second_data, hdr.second_size);
218    SHA_update(&ctx, &hdr.second_size, sizeof(hdr.second_size));
219    sha = SHA_final(&ctx);
220    memcpy(hdr.id, sha,
221           SHA_DIGEST_SIZE > sizeof(hdr.id) ? sizeof(hdr.id) : SHA_DIGEST_SIZE);
222
223    fd = open(bootimg, O_CREAT | O_TRUNC | O_WRONLY, 0644);
224    if(fd < 0) {
225        fprintf(stderr,"error: could not create '%s'\n", bootimg);
226        return 1;
227    }
228
229    if(write(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) goto fail;
230    if(write_padding(fd, pagesize, sizeof(hdr))) goto fail;
231
232    if(write(fd, kernel_data, hdr.kernel_size) != hdr.kernel_size) goto fail;
233    if(write_padding(fd, pagesize, hdr.kernel_size)) goto fail;
234
235    if(write(fd, ramdisk_data, hdr.ramdisk_size) != hdr.ramdisk_size) goto fail;
236    if(write_padding(fd, pagesize, hdr.ramdisk_size)) goto fail;
237
238    if(second_data) {
239        if(write(fd, second_data, hdr.second_size) != hdr.second_size) goto fail;
240        if(write_padding(fd, pagesize, hdr.ramdisk_size)) goto fail;
241    }
242
243    return 0;
244
245fail:
246    unlink(bootimg);
247    close(fd);
248    fprintf(stderr,"error: failed writing '%s': %s\n", bootimg,
249            strerror(errno));
250    return 1;
251}
252