Add config for rdo

This is needed for #1.

Makefile

@@ -6,10 +6,11 @@ install: rdo
 	chown root:root /usr/bin/rdo
 	chmod 755 /usr/bin/rdo
 	chmod u+s /usr/bin/rdo
-	mkdir -p /etc/rdo
+	cp rdo_sample.conf /etc/rdo.conf
 
 uninstall:
 	rm /usr/bin/rdo
-	rm -rf /etc/rdo
+	rm /etc/rdo.conf
+
 clean:
 	rm rdo

README.md

@@ -12,9 +12,7 @@ sudo make install
 ```
 
 After that, you'll have to configure rdo to allow you to use it.
-```sh
+To do this, edit `/etc/rdo.conf`, and set the username variable to your own.
-echo "YourUsername" | sudo tee /etc/rdo/username
-```
 
 After that you're good to go!
 

rdo.c

@@ -7,13 +7,34 @@
 #include <string.h>
 #include <bsd/readpassphrase.h>
 
+int getconf(FILE* fp, const char* entry, char* result, size_t len_result) {
+	char* line = NULL;
+	size_t len = 0;
+
+	fseek(fp, 0, SEEK_SET);
+
+	while (getline(&line, &len, fp) != -1) {
+		if (strncmp(entry, line, strlen(entry)) == 0) {
+			strtok(line, "=");
+			char* token = strtok(NULL, "=");
+			if (token) {
+				strncpy(result, token, len_result);
+				result[strcspn(result, "\n")] = 0;
+				return 0;
+			}
+		}
+	}
+
+	return 1;
+}
+
 void runprog(int argc, char** argv) {
 	for(int i=0; i<argc; i++)
 		argv[i] = argv[i + 1];
 
 	setuid(0);
 	setgid(0);
-	
+
 	if (execvp(argv[0], argv) != 0) 
 		perror(argv[0]);
 }
@@ -22,10 +43,10 @@ int main(int argc, char** argv) {
 	if (argc < 2)
 		errx(1, "Please specify a program to run");
 
-	FILE* fp = fopen("/etc/rdo/username", "r");
+	FILE* fp = fopen("/etc/rdo.conf", "r");
 	
 	if (!fp)
-		err(1, "Could not open /etc/rdo/username");
+		err(1, "Could not open /etc/rdo.conf");
 
 	int ruid = getuid();
 	if (ruid == 0) {
@@ -35,9 +56,7 @@ int main(int argc, char** argv) {
 	}
 
 	char username[64];
-	fgets(username, 64, fp);
+	getconf(fp, "username", username, sizeof(username));
-	fclose(fp);
-	username[strcspn(username, "\n")] = 0;
 
 	struct passwd* p = getpwnam(username);
 	if (!p)

rdo_sample.conf

@@ -0,0 +1 @@
+username=sw1tchbl4d3