mkbootimg.c revision 65e461c478b000246ef81c3ca5fdd2dbb819d7ad 
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            "       [ --pagesize <pagesize> ]\n"
68            "       -o|--output <filename>\n"
69            );
70    return 1;
71}
72
73
74
75static unsigned char padding[4096] = { 0, };
76
77int write_padding(int fd, unsigned pagesize, unsigned itemsize)
78{
79    unsigned pagemask = pagesize - 1;
80    unsigned count;
81
82    if((itemsize & pagemask) == 0) {
83        return 0;
84    }
85
86    count = pagesize - (itemsize & pagemask);
87
88    if(write(fd, padding, count) != count) {
89        return -1;
90    } else {
91        return 0;
92    }
93}
94
95int main(int argc, char **argv)
96{
97    boot_img_hdr hdr;
98
99    char *kernel_fn = 0;
100    void *kernel_data = 0;
101    char *ramdisk_fn = 0;
102    void *ramdisk_data = 0;
103    char *second_fn = 0;
104    void *second_data = 0;
105    char *cmdline = "";
106    char *bootimg = 0;
107    char *board = "";
108    unsigned pagesize = 2048;
109    int fd;
110    SHA_CTX ctx;
111    uint8_t* sha;
112
113    argc--;
114    argv++;
115
116    memset(&hdr, 0, sizeof(hdr));
117
118        /* default load addresses */
119    hdr.kernel_addr =  0x10008000;
120    hdr.ramdisk_addr = 0x11000000;
121    hdr.second_addr =  0x10F00000;
122    hdr.tags_addr =    0x10000100;
123
124    while(argc > 0){
125        char *arg = argv[0];
126        char *val = argv[1];
127        if(argc < 2) {
128            return usage();
129        }
130        argc -= 2;
131        argv += 2;
132        if(!strcmp(arg, "--output") || !strcmp(arg, "-o")) {
133            bootimg = val;
134        } else if(!strcmp(arg, "--kernel")) {
135            kernel_fn = val;
136        } else if(!strcmp(arg, "--ramdisk")) {
137            ramdisk_fn = val;
138        } else if(!strcmp(arg, "--second")) {
139            second_fn = val;
140        } else if(!strcmp(arg, "--cmdline")) {
141            cmdline = val;
142        } else if(!strcmp(arg, "--base")) {
143            unsigned base = strtoul(val, 0, 16);
144            hdr.kernel_addr =  base + 0x00008000;
145            hdr.ramdisk_addr = base + 0x01000000;
146            hdr.second_addr =  base + 0x00F00000;
147            hdr.tags_addr =    base + 0x00000100;
148        } else if(!strcmp(arg, "--board")) {
149            board = val;
150        } else if(!strcmp(arg,"--pagesize")) {
151            pagesize = strtoul(val, 0, 10);
152            if ((pagesize != 2048) && (pagesize != 4096)) {
153                fprintf(stderr,"error: unsupported page size %d\n", pagesize);
154                return -1;
155            }
156        } else {
157            return usage();
158        }
159    }
160    hdr.page_size = pagesize;
161
162
163    if(bootimg == 0) {
164        fprintf(stderr,"error: no output filename specified\n");
165        return usage();
166    }
167
168    if(kernel_fn == 0) {
169        fprintf(stderr,"error: no kernel image specified\n");
170        return usage();
171    }
172
173    if(ramdisk_fn == 0) {
174        fprintf(stderr,"error: no ramdisk image specified\n");
175        return usage();
176    }
177
178    if(strlen(board) >= BOOT_NAME_SIZE) {
179        fprintf(stderr,"error: board name too large\n");
180        return usage();
181    }
182
183    strcpy(hdr.name, board);
184
185    memcpy(hdr.magic, BOOT_MAGIC, BOOT_MAGIC_SIZE);
186
187    if(strlen(cmdline) > (BOOT_ARGS_SIZE - 1)) {
188        fprintf(stderr,"error: kernel commandline too large\n");
189        return 1;
190    }
191    strcpy((char*)hdr.cmdline, cmdline);
192
193    kernel_data = load_file(kernel_fn, &hdr.kernel_size);
194    if(kernel_data == 0) {
195        fprintf(stderr,"error: could not load kernel '%s'\n", kernel_fn);
196        return 1;
197    }
198
199    if(!strcmp(ramdisk_fn,"NONE")) {
200        ramdisk_data = 0;
201        hdr.ramdisk_size = 0;
202    } else {
203        ramdisk_data = load_file(ramdisk_fn, &hdr.ramdisk_size);
204        if(ramdisk_data == 0) {
205            fprintf(stderr,"error: could not load ramdisk '%s'\n", ramdisk_fn);
206            return 1;
207        }
208    }
209
210    if(second_fn) {
211        second_data = load_file(second_fn, &hdr.second_size);
212        if(second_data == 0) {
213            fprintf(stderr,"error: could not load secondstage '%s'\n", second_fn);
214            return 1;
215        }
216    }
217
218    /* put a hash of the contents in the header so boot images can be
219     * differentiated based on their first 2k.
220     */
221    SHA_init(&ctx);
222    SHA_update(&ctx, kernel_data, hdr.kernel_size);
223    SHA_update(&ctx, &hdr.kernel_size, sizeof(hdr.kernel_size));
224    SHA_update(&ctx, ramdisk_data, hdr.ramdisk_size);
225    SHA_update(&ctx, &hdr.ramdisk_size, sizeof(hdr.ramdisk_size));
226    SHA_update(&ctx, second_data, hdr.second_size);
227    SHA_update(&ctx, &hdr.second_size, sizeof(hdr.second_size));
228    sha = SHA_final(&ctx);
229    memcpy(hdr.id, sha,
230           SHA_DIGEST_SIZE > sizeof(hdr.id) ? sizeof(hdr.id) : SHA_DIGEST_SIZE);
231
232    fd = open(bootimg, O_CREAT | O_TRUNC | O_WRONLY, 0644);
233    if(fd < 0) {
234        fprintf(stderr,"error: could not create '%s'\n", bootimg);
235        return 1;
236    }
237
238    if(write(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) goto fail;
239    if(write_padding(fd, pagesize, sizeof(hdr))) goto fail;
240
241    if(write(fd, kernel_data, hdr.kernel_size) != hdr.kernel_size) goto fail;
242    if(write_padding(fd, pagesize, hdr.kernel_size)) goto fail;
243
244    if(write(fd, ramdisk_data, hdr.ramdisk_size) != hdr.ramdisk_size) goto fail;
245    if(write_padding(fd, pagesize, hdr.ramdisk_size)) goto fail;
246
247    if(second_data) {
248        if(write(fd, second_data, hdr.second_size) != hdr.second_size) goto fail;
249        if(write_padding(fd, pagesize, hdr.ramdisk_size)) goto fail;
250    }
251
252    return 0;
253
254fail:
255    unlink(bootimg);
256    close(fd);
257    fprintf(stderr,"error: failed writing '%s': %s\n", bootimg,
258            strerror(errno));
259    return 1;
260}
261