aindump: add decrypt mode

Add -d,--decrypt option to dump decrypted ain file (for reverse
engineering).

include/system4/ain.h

@@ -237,6 +237,7 @@ struct ain {
 
 const char *ain_strerror(int error);
 const char *ain_strtype(struct ain *ain, enum ain_data_type type, int struct_type);
+uint8_t *ain_read(const char *path, long *len, int *error);
 struct ain *ain_open(const char *path, int *error);
 void ain_free(struct ain *ain);
 

src/ain.c

@@ -594,12 +594,10 @@ static bool ain_is_encrypted(uint8_t *buf)
 	return !strncmp((char*)magic, "VERS", 4) && !magic[5] && !magic[6] && !magic[7];
 }
 
-struct ain *ain_open(const char *path, int *error)
+uint8_t *ain_read(const char *path, long *len, int *error)
 {
 	FILE *fp;
-	long len;
 	uint8_t *buf = NULL;
-	struct ain *ain = NULL;
 
 	if (!(fp = fopen(path, "rb"))) {
 		*error = AIN_FILE_ERROR;
@@ -608,17 +606,17 @@ struct ain *ain_open(const char *path, int *error)
 
 	// get size of AIN file
 	fseek(fp, 0, SEEK_END);
-	len = ftell(fp);
+	*len = ftell(fp);
 	fseek(fp, 0, SEEK_SET);
 
 	// read AIN file into memory
-	buf = xmalloc(len + 4); // why +4?
-	fread(buf, 1, len, fp);
+	buf = xmalloc(*len + 4); // why +4?
+	fread(buf, 1, *len, fp);
 	fclose(fp);
 
 	// check magic
 	if (!strncmp((char*)buf, "AI2\0\0\0\0", 8)) {
-		uint8_t *uc = decompress_ain(buf, &len);
+		uint8_t *uc = decompress_ain(buf, len);
 		if (!uc) {
 			*error = AIN_INVALID;
 			goto err;
@@ -626,13 +624,25 @@ struct ain *ain_open(const char *path, int *error)
 		free(buf);
 		buf = uc;
 	} else if (ain_is_encrypted(buf)) {
-		decrypt_ain(buf, len);
+		decrypt_ain(buf, *len);
 	} else {
 		printf("%.4s\n", buf);
 		*error = AIN_UNRECOGNIZED_FORMAT;
 		goto err;
 	}
 
+	return buf;
+err:
+	free(buf);
+	return NULL;
+}
+
+struct ain *ain_open(const char *path, int *error)
+{
+	long len;
+	struct ain *ain = NULL;
+	uint8_t *buf = ain_read(path, &len, error);
+
 	// read data into ain struct
 	struct ain_reader r = {
 		.buf = buf,

src/aindump/aindump.c

@@ -92,6 +92,7 @@ static void print_function(FILE *out, struct ain *ain, struct ain_function *f)
 static void ain_dump_functions(FILE *f, struct ain *ain)
 {
 	for (int i = 0; i < ain->nr_functions; i++) {
+		fprintf(f, "0x%x:\t", i);
 		print_function(f, ain, &ain->functions[i]);
 	}
 }
@@ -244,6 +245,21 @@ static void ain_audit(FILE *f, struct ain *ain)
 	fflush(f);
 }
 
+static void ain_decrypt(FILE *f, const char *path)
+{
+	int err;
+	long len;
+	uint8_t *ain;
+
+	if (!(ain = ain_read(path, &len, &err))) {
+		ERROR("Failed to open ain file: %s\n", ain_strerror(err));
+	}
+
+	fwrite(ain, len, 1, f);
+	fflush(f);
+	free(ain);
+}
+
 int main(int argc, char *argv[])
 {
 	bool dump_version = false;
@@ -260,6 +276,7 @@ int main(int argc, char *argv[])
 	bool dump_global_group_names = false;
 	bool dump_enums = false;
 	bool audit = false;
+	bool decrypt = false;
 	char *output_file = NULL;
 	FILE *output = stdout;
 	int err = AIN_SUCCESS;
@@ -282,12 +299,13 @@ int main(int argc, char *argv[])
 			{ "global-group-names", no_argument,       0, 'r' },
 			{ "enums",              no_argument,       0, 'e' },
 			{ "audit",              no_argument,       0, 'A' },
+			{ "decrypt",            no_argument,       0, 'd' },
 			{ "output",             required_argument, 0, 'o' },
 		};
 		int option_index = 0;
 		int c;
 
-		c = getopt_long(argc, argv, "hVcCfgSmlsFeAo:", long_options, &option_index);
+		c = getopt_long(argc, argv, "hVcCfgSmlsFeAdo:", long_options, &option_index);
 		if (c == -1)
 			break;
 
@@ -337,6 +355,9 @@ int main(int argc, char *argv[])
 		case 'A':
 			audit = true;
 			break;
+		case 'd':
+			decrypt = true;
+			break;
 		case 'o':
 			output_file = xstrdup(optarg);
 			break;
@@ -360,6 +381,11 @@ int main(int argc, char *argv[])
 		free(output_file);
 	}
 
+	if (decrypt) {
+		ain_decrypt(output, argv[0]);
+		return 0;
+	}
+
 	if (!(ain = ain_open(argv[0], &err))) {
 		ERROR("Failed to open ain file: %s\n", ain_strerror(err));
 		return 1;
@@ -395,4 +421,5 @@ int main(int argc, char *argv[])
 		ain_audit(output, ain);
 
 	ain_free(ain);
+	return 0;
 }