Cleanup hexpatch

This commit is contained in:
topjohnwu 2017-02-25 03:50:26 +08:00
parent 7ef0746c52
commit 2ccd8b8838

View File

@ -6,6 +6,7 @@
#include <fcntl.h> #include <fcntl.h>
#include <stdlib.h> #include <stdlib.h>
#include <string.h> #include <string.h>
#include <sys/mman.h>
#include "bootimg.h" #include "bootimg.h"
@ -17,13 +18,13 @@ static int hex2int(char c) {
return result; return result;
} }
static int hex2ascii(char c, char d) { static unsigned hex2ascii(char c, char d) {
int high = hex2int(c) * 16; int high = hex2int(c) * 16;
int low = hex2int(d); int low = hex2int(d);
return high+low; return high + low;
} }
static void hexstr2str(char *hex, char *str) { static void hexstr2str(char *hex, unsigned char *str) {
char buf = 0; char buf = 0;
for(int i = 0, length = strlen(hex); i < length; ++i){ for(int i = 0, length = strlen(hex); i < length; ++i){
if(i % 2){ if(i % 2){
@ -36,29 +37,23 @@ static void hexstr2str(char *hex, char *str) {
int hexpatch(char * image, char *from, char *to) { int hexpatch(char * image, char *from, char *to) {
int fd = open(image, O_RDWR), patternsize = strlen(from) / 2, patchsize = strlen(to) / 2; int fd = open(image, O_RDWR), patternsize = strlen(from) / 2, patchsize = strlen(to) / 2;
off_t filesize = lseek(fd, 0, SEEK_END); size_t filesize = lseek(fd, 0, SEEK_END);
char *file, *pattern, *patch, *start;
file = malloc(sizeof (char) * filesize);
pattern = malloc(sizeof (char) * patternsize);
patch = malloc(sizeof (char) * patchsize);
lseek(fd, 0, SEEK_SET); lseek(fd, 0, SEEK_SET);
read(fd, file, filesize); unsigned char *file, *pattern, *patch;
file = mmap(NULL, filesize, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
pattern = malloc(patternsize);
patch = malloc(patchsize);
hexstr2str(from, pattern); hexstr2str(from, pattern);
hexstr2str(to, patch); hexstr2str(to, patch);
for (off_t i = 0; i < filesize;) { for (size_t i = 0; i < filesize - patternsize; ++i) {
int j; if (memcmp(file + i, pattern, patternsize) == 0) {
for (j = 0; j < patternsize; ++j) { printf("Pattern %s found!\nPatching to %s\n", from, to);
if(file[i + j] != pattern[j]) break; memset(file + i, 0, patternsize);
memcpy(file + i, patch, patchsize);
i += patternsize - 1;
} }
if (j == patternsize) {
fprintf(stderr, "Pattern %s found!\nPatching to %s\n", from, to);
lseek(fd, i, SEEK_SET);
write(fd, patch, patchsize);
}
if(j == 0) j = 1;
i += j;
} }
free(file); munmap(file, filesize);
free(pattern); free(pattern);
free(patch); free(patch);
close(fd); close(fd);