Add extract, repack, hexpatch, sepolicy-injection

jni/hexpatch.c

@@ -0,0 +1,66 @@
+#include <getopt.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "bootimgtools.h"
+
+int hex2int(char c) {
+	int first = c / 16 - 3;
+	int second = c % 16;
+	int result = first * 10 + second;
+	if(result > 9) result--;
+	return result;
+}
+
+int hex2ascii(char c, char d) {
+	int high = hex2int(c) * 16;
+	int low = hex2int(d);
+	return high+low;
+}
+
+void hexstr2str(char *hex, char *str) {
+	char buf = 0;
+	for(int i = 0, length = strlen(hex); i < length; ++i){
+		if(i % 2){
+			str[i / 2] = hex2ascii(buf, hex[i]);
+		} else{
+			buf = hex[i];
+		}
+	}
+}
+
+int hexpatch(char * image, char *from, char *to) {
+	int fd = open(image, O_RDWR), patternsize = strlen(from) / 2, patchsize = strlen(to) / 2;
+	off_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);
+	read(fd, file, filesize);
+	hexstr2str(from, pattern);
+	hexstr2str(to, patch);
+	for (off_t i = 0; i < filesize;) {
+		int j;
+		for (j = 0; j < patternsize; ++j) {
+			if(file[i + j] != pattern[j]) break;
+		}
+		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);
+	free(pattern);
+	free(patch);
+	close(fd);
+	return 0;
+}