mkbootimg.c revision 8417d698cff733f3c5de08f2fa96b67bf4a9f795 
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            "       [ --base <address> ]\n"
67            "       -o|--output <filename>\n"
68            );
69    return 1;
70}
71
72
73
74static unsigned char padding[4096] = { 0, };
75
76int 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
94int 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 if(!strcmp(arg,"--pagesize")) {
152            pagesize = strtoul(val, 0, 10);
153            if ((pagesize != 2048) && (pagesize != 4096)) {
154                fprintf(stderr,"error: unsupported page size %d\n", pagesize);
155                return -1;
156            }
157        } else {
158            return usage();
159        }
160    }
161
162    if(bootimg == 0) {
163        fprintf(stderr,"error: no output filename specified\n");
164        return usage();
165    }
166
167    if(kernel_fn == 0) {
168        fprintf(stderr,"error: no kernel image specified\n");
169        return usage();
170    }
171
172    if(ramdisk_fn == 0) {
173        fprintf(stderr,"error: no ramdisk image specified\n");
174        return usage();
175    }
176
177    if(strlen(board) >= BOOT_NAME_SIZE) {
178        fprintf(stderr,"error: board name too large\n");
179        return usage();
180    }
181
182    strcpy(hdr.name, board);
183
184    memcpy(hdr.magic, BOOT_MAGIC, BOOT_MAGIC_SIZE);
185
186    if(strlen(cmdline) > (BOOT_ARGS_SIZE - 1)) {
187        fprintf(stderr,"error: kernel commandline too large\n");
188        return 1;
189    }
190    strcpy((char*)hdr.cmdline, cmdline);
191
192    kernel_data = load_file(kernel_fn, &hdr.kernel_size);
193    if(kernel_data == 0) {
194        fprintf(stderr,"error: could not load kernel '%s'\n", kernel_fn);
195        return 1;
196    }
197
198    if(!strcmp(ramdisk_fn,"NONE")) {
199        ramdisk_data = 0;
200        hdr.ramdisk_size = 0;
201    } else {
202        ramdisk_data = load_file(ramdisk_fn, &hdr.ramdisk_size);
203        if(ramdisk_data == 0) {
204            fprintf(stderr,"error: could not load ramdisk '%s'\n", ramdisk_fn);
205            return 1;
206        }
207    }
208
209    if(second_fn) {
210        second_data = load_file(second_fn, &hdr.second_size);
211        if(second_data == 0) {
212            fprintf(stderr,"error: could not load secondstage '%s'\n", second_fn);
213            return 1;
214        }
215    }
216
217    /* put a hash of the contents in the header so boot images can be
218     * differentiated based on their first 2k.
219     */
220    SHA_init(&ctx);
221    SHA_update(&ctx, kernel_data, hdr.kernel_size);
222    SHA_update(&ctx, &hdr.kernel_size, sizeof(hdr.kernel_size));
223    SHA_update(&ctx, ramdisk_data, hdr.ramdisk_size);
224    SHA_update(&ctx, &hdr.ramdisk_size, sizeof(hdr.ramdisk_size));
225    SHA_update(&ctx, second_data, hdr.second_size);
226    SHA_update(&ctx, &hdr.second_size, sizeof(hdr.second_size));
227    sha = SHA_final(&ctx);
228    memcpy(hdr.id, sha,
229           SHA_DIGEST_SIZE > sizeof(hdr.id) ? sizeof(hdr.id) : SHA_DIGEST_SIZE);
230
231    fd = open(bootimg, O_CREAT | O_TRUNC | O_WRONLY, 0644);
232    if(fd < 0) {
233        fprintf(stderr,"error: could not create '%s'\n", bootimg);
234        return 1;
235    }
236
237    if(write(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) goto fail;
238    if(write_padding(fd, pagesize, sizeof(hdr))) goto fail;
239
240    if(write(fd, kernel_data, hdr.kernel_size) != hdr.kernel_size) goto fail;
241    if(write_padding(fd, pagesize, hdr.kernel_size)) goto fail;
242
243    if(write(fd, ramdisk_data, hdr.ramdisk_size) != hdr.ramdisk_size) goto fail;
244    if(write_padding(fd, pagesize, hdr.ramdisk_size)) goto fail;
245
246    if(second_data) {
247        if(write(fd, second_data, hdr.second_size) != hdr.second_size) goto fail;
248        if(write_padding(fd, pagesize, hdr.ramdisk_size)) goto fail;
249    }
250
251    return 0;
252
253fail:
254    unlink(bootimg);
255    close(fd);
256    fprintf(stderr,"error: failed writing '%s': %s\n", bootimg,
257            strerror(errno));
258    return 1;
259}
260