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mirror of https://github.com/anestisb/android-unpackbootimg.git synced 2024-05-16 19:09:31 +00:00
android-unpackbootimg/unpackbootimg.c

339 lines
10 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <limits.h>
#include <libgen.h>
#include <sys/stat.h>
#include "mincrypt/sha.h"
#include "bootimg.h"
typedef unsigned char byte;
int read_padding(FILE* f, unsigned itemsize, int pagesize)
{
byte* buf = (byte*)malloc(sizeof(byte) * pagesize);
unsigned pagemask = pagesize - 1;
unsigned count;
if((itemsize & pagemask) == 0) {
free(buf);
return 0;
}
count = pagesize - (itemsize & pagemask);
if(fread(buf, count, 1, f)){};
free(buf);
return count;
}
int write_string_to_file(const char* file, const char* string)
{
// Try to create a directory first.
char* fcopy = strdup(file);
mkdir(dirname(fcopy), 0777);
free(fcopy);
FILE* f = fopen(file, "w");
if (!f) {
printf("File %s can't be opened.\n", file);
return 1;
}
fwrite(string, strlen(string), 1, f);
fwrite("\n", 1, 1, f);
fclose(f);
return 0;
}
const char *detect_hash_type(const struct boot_img_hdr *hdr)
{
/*
* This isn't a sophisticated or 100% reliable method to detect the hash
* type but it's probably good enough.
*
* sha256 is expected to have no zeroes in the id array
* sha1 is expected to have zeroes in id[5], id[6] and id[7]
* Zeroes anywhere else probably indicates neither.
*/
const uint32_t *id = hdr->id;
if (id[0] != 0 && id[1] != 0 && id[2] != 0 && id[3] != 0 &&
id[4] != 0 && id[5] != 0 && id[6] != 0 && id[7] != 0)
return "sha256";
else if (id[0] != 0 && id[1] != 0 && id[2] != 0 && id[3] != 0 &&
id[4] != 0 && id[5] == 0 && id[6] == 0 && id[7] == 0)
return "sha1";
else
return "unknown";
}
int usage() {
printf("usage: unpackbootimg\n");
printf("\t-i|--input boot.img\n");
printf("\t[ -o|--output output_directory]\n");
printf("\t[ -p|--pagesize <size-in-hexadecimal> ]\n");
return 0;
}
int main(int argc, char** argv)
{
char tmp[PATH_MAX];
char* directory = "./";
char* filename = NULL;
int pagesize = 0;
int base = 0;
argc--;
argv++;
while(argc > 0){
char *arg = argv[0];
char *val = argv[1];
argc -= 2;
argv += 2;
if(!strcmp(arg, "--input") || !strcmp(arg, "-i")) {
filename = val;
} else if(!strcmp(arg, "--output") || !strcmp(arg, "-o")) {
directory = val;
} else if(!strcmp(arg, "--pagesize") || !strcmp(arg, "-p")) {
pagesize = strtoul(val, 0, 16);
} else {
return usage();
}
}
if (filename == NULL) {
return usage();
}
int total_read = 0;
FILE* f = fopen(filename, "rb");
if (!f) {
printf("Input file not found.\n");
return 1;
}
boot_img_hdr header;
//printf("Reading header...\n");
int i;
int seeklimit = 65536;
for (i = 0; i <= seeklimit; i++) {
fseek(f, i, SEEK_SET);
if(fread(tmp, BOOT_MAGIC_SIZE, 1, f)){};
if (memcmp(tmp, BOOT_MAGIC, BOOT_MAGIC_SIZE) == 0)
break;
}
total_read = i;
if (i > seeklimit) {
printf("Android boot magic not found.\n");
return 1;
}
fseek(f, i, SEEK_SET);
if (i > 0) {
printf("Android magic found at: %d\n", i);
}
if(fread(&header, sizeof(header), 1, f)){};
base = header.kernel_addr - 0x00008000;
printf("BOARD_KERNEL_CMDLINE %s\n", header.cmdline);
printf("BOARD_KERNEL_BASE %08x\n", base);
printf("BOARD_NAME %s\n", header.name);
printf("BOARD_PAGE_SIZE %d\n", header.page_size);
printf("BOARD_HASH_TYPE %s\n", detect_hash_type(&header));
printf("BOARD_KERNEL_OFFSET %08x\n", header.kernel_addr - base);
printf("BOARD_RAMDISK_OFFSET %08x\n", header.ramdisk_addr - base);
printf("BOARD_SECOND_OFFSET %08x\n", header.second_addr - base);
printf("BOARD_TAGS_OFFSET %08x\n", header.tags_addr - base);
int a, b, c, y, m;
a = b = c = y = m = 0;
if (header.os_version != 0) {
int os_version,os_patch_level;
os_version = header.os_version >> 11;
os_patch_level = header.os_version&0x7ff;
a = (os_version >> 14)&0x7f;
b = (os_version >> 7)&0x7f;
c = os_version&0x7f;
y = (os_patch_level >> 4) + 2000;
m = os_patch_level&0xf;
if((a < 128) && (b < 128) && (c < 128) && (y >= 2000) && (y < 2128) && (m > 0) && (m <= 12)) {
printf("BOARD_OS_VERSION %d.%d.%d\n", a, b, c);
printf("BOARD_OS_PATCH_LEVEL %d-%02d\n", y, m);
} else {
header.os_version = 0;
}
}
if (header.dt_size != 0) {
printf("BOARD_DT_SIZE %d\n", header.dt_size);
}
if (pagesize == 0) {
pagesize = header.page_size;
}
//printf("cmdline...\n");
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-cmdline");
write_string_to_file(tmp, (char *)header.cmdline);
//printf("board...\n");
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-board");
write_string_to_file(tmp, (char *)header.name);
//printf("base...\n");
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-base");
char basetmp[200];
sprintf(basetmp, "%08x", base);
write_string_to_file(tmp, basetmp);
//printf("pagesize...\n");
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-pagesize");
char pagesizetmp[200];
sprintf(pagesizetmp, "%d", header.page_size);
write_string_to_file(tmp, pagesizetmp);
//printf("kerneloff...\n");
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-kerneloff");
char kernelofftmp[200];
sprintf(kernelofftmp, "%08x", header.kernel_addr - base);
write_string_to_file(tmp, kernelofftmp);
//printf("ramdiskoff...\n");
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-ramdiskoff");
char ramdiskofftmp[200];
sprintf(ramdiskofftmp, "%08x", header.ramdisk_addr - base);
write_string_to_file(tmp, ramdiskofftmp);
//printf("secondoff...\n");
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-secondoff");
char secondofftmp[200];
sprintf(secondofftmp, "%08x", header.second_addr - base);
write_string_to_file(tmp, secondofftmp);
//printf("tagsoff...\n");
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-tagsoff");
char tagsofftmp[200];
sprintf(tagsofftmp, "%08x", header.tags_addr - base);
write_string_to_file(tmp, tagsofftmp);
if (header.os_version != 0) {
//printf("os_version...\n");
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-osversion");
char osvertmp[200];
sprintf(osvertmp, "%d.%d.%d", a, b, c);
write_string_to_file(tmp, osvertmp);
//printf("os_patch_level...\n");
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-oslevel");
char oslvltmp[200];
sprintf(oslvltmp, "%d-%02d", y, m);
write_string_to_file(tmp, oslvltmp);
}
//printf("hash...\n");
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-hash");
const char *hashtype = detect_hash_type(&header);
write_string_to_file(tmp, hashtype);
total_read += sizeof(header);
//printf("total read: %d\n", total_read);
total_read += read_padding(f, sizeof(header), pagesize);
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-zImage");
FILE *k = fopen(tmp, "wb");
byte* kernel = (byte*)malloc(header.kernel_size);
//printf("Reading kernel...\n");
if(fread(kernel, header.kernel_size, 1, f)){};
total_read += header.kernel_size;
fwrite(kernel, header.kernel_size, 1, k);
fclose(k);
//printf("total read: %d\n", header.kernel_size);
total_read += read_padding(f, header.kernel_size, pagesize);
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-ramdisk.gz");
FILE *r = fopen(tmp, "wb");
byte* ramdisk = (byte*)malloc(header.ramdisk_size);
//printf("Reading ramdisk...\n");
if(fread(ramdisk, header.ramdisk_size, 1, f)){};
total_read += header.ramdisk_size;
fwrite(ramdisk, header.ramdisk_size, 1, r);
fclose(r);
//printf("total read: %d\n", header.ramdisk_size);
total_read += read_padding(f, header.ramdisk_size, pagesize);
/*
* Even though the second_size is 0, some vendors may place a signature
* image there. In such a case read to EOF and try to calculate the
* size based on termination with a null, then fix it in header.
*/
if (header.second_size == 0) {
struct stat st;
stat(filename, &st);
int second_test_size = st.st_size - total_read;
if (second_test_size > header.dt_size) {
byte* second_test = (byte*)malloc(second_test_size);
if(fread(second_test, second_test_size, 1, f)){};
u_int16_t *sbuf = (u_int16_t*)second_test;
if (sbuf[0]) {
int second_size = 0;
while (sbuf[0]) {
second_size += 2;
sbuf++;
}
if ((second_size >= 1024) && (second_size < 2048))
header.second_size = second_size;
}
fseek(f, total_read, SEEK_SET);
}
}
if (header.second_size != 0) {
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-second");
FILE *s = fopen(tmp, "wb");
byte* second = (byte*)malloc(header.second_size);
//printf("Reading second...\n");
if(fread(second, header.second_size, 1, f)){};
total_read += header.second_size;
fwrite(second, header.second_size, 1, s);
fclose(s);
}
//printf("total read: %d\n", header.second_size);
total_read += read_padding(f, header.second_size, pagesize);
if (header.dt_size != 0) {
sprintf(tmp, "%s/%s", directory, basename(filename));
strcat(tmp, "-dtb");
FILE *d = fopen(tmp, "wb");
byte* dtb = (byte*)malloc(header.dt_size);
//printf("Reading dtb...\n");
if(fread(dtb, header.dt_size, 1, f)){};
total_read += header.dt_size;
fwrite(dtb, header.dt_size, 1, d);
fclose(d);
}
fclose(f);
//printf("Total Read: %d\n", total_read);
return 0;
}