1 #include <u.h>
2 #include <libc.h>
3 #include <auth.h>
4 
5 /*
6  *  become the authenticated user
7  */
8 int
9 auth_chuid(AuthInfo *ai, char *ns)
10 {
11 	int rv, fd;
12 
13 	if(ai == nil || ai->cap == nil){
14 		werrstr("no capability");
15 		return -1;
16 	}
17 
18 	/* change uid */
19 	fd = open("#¤/capuse", OWRITE);
20 	if(fd < 0){
21 		werrstr("opening #¤/capuse: %r");
22 		return -1;
23 	}
24 	rv = write(fd, ai->cap, strlen(ai->cap));
25 	close(fd);
26 	if(rv < 0){
27 		werrstr("writing %s to #¤/capuse: %r", ai->cap);
28 		return -1;
29 	}
30 
31 	/* get a link to factotum as new user */
32 	fd = open("/srv/factotum", ORDWR);
33 	if(fd >= 0)
34 		mount(fd, -1, "/mnt", MREPL, "");
35 
36 	/* set up new namespace */
37 	return newns(ai->cuid, ns);
38 }