correctly set group and permissions on socket on startup

1 files changed, 39 insertions, 0 deletions

diff --git a/thing.c b/thing.c
index e7c0f53..b3854ae 100644
--- a/thing.c
+++ b/thing.c
@@ -19,10 +19,12 @@
 #define REALNAME ",flappy fly bird man?"
 #define CHANNEL "#a"
 
+#define SOCKETGROUP "apionet"
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <grp.h>
 #include <errno.h>
 #include <string.h>
 #include <sys/types.h>
@@ -183,6 +185,43 @@ int unix_setup() {
 		perror("(unix) bind");
 		return -1;
 	}
+
+	// set group and permissions on socket
+	long buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
+	buflen = (buflen == -1) ? 1024 : buflen;
+	char *buf = malloc(buflen);
+	struct group grp;
+	struct group *res;
+	errno = 0;
+	// get group gid from name
+	getgrnam_r(SOCKETGROUP,&grp,buf,buflen,&res);
+	if (res == NULL) {
+		if (errno != 0)
+			perror("getgrnam_r");
+		else
+			fprintf(stderr,"group %s does not exist",SOCKETGROUP);
+		free(buf);
+		return -1;
+	}
+	free(buf);
+
+	// set socket's group
+	if (chown(SOCKETNAME,-1,grp.gr_gid) == -1) {
+		perror("chown");
+		return -1;
+	}
+
+	struct stat sb;
+	if (stat(SOCKETNAME,&sb) == -1) {
+		perror("stat");
+		return -1;
+	}
+	if (chmod(SOCKETNAME,sb.st_mode|S_IWGRP) == -1) {
+		perror("chmod");
+		return -1;
+	}
+	
+	
 	return sock;
 }