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/* $OpenBSD: getpeereid_test.c,v 1.4 2017/03/08 19:28:47 deraadt Exp $ */
/* Written by Marc Espie in 2006 */
/* Public domain */
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/un.h>
#include <sys/wait.h>
#include <err.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
char path[1024];
char *dir;
char *
check_id(int fd)
{
uid_t sockuid, myuid;
gid_t sockgid, mygid;
static char problem[1024];
if (getpeereid(fd, &sockuid, &sockgid) == -1) {
snprintf(problem, sizeof problem, "getpeereid: %s",
strerror(errno));
return problem;
}
myuid = geteuid();
mygid = getgid();
if (myuid != sockuid) {
snprintf(problem, sizeof problem, "uid discrepancy %ld vs %ld",
(long)myuid, (long)sockuid);
return problem;
}
if (mygid != sockgid) {
snprintf(problem, sizeof problem, "gid discrepancy %ld vs %ld",
(long)mygid, (long)sockgid);
return problem;
}
return NULL;
}
void
client(struct sockaddr_un *sun)
{
int s;
int i;
int r;
char *problem;
s = socket(AF_UNIX, SOCK_STREAM, 0);
if (s == -1)
err(1, "Bad socket");
/* XXX make sure the server started alright */
for (i = 0; i < 10; i++) {
r = connect(s, (struct sockaddr *)sun, sizeof(*sun));
if (r == 0) {
problem = check_id(s);
if (problem)
errx(1, "%s", problem);
exit(0);
}
sleep(5);
}
errx(1, "Could not connect after 10 tries");
}
void
server(struct sockaddr_un *sun)
{
int s, fd;
struct sockaddr_storage client_addr;
socklen_t client_len;
char *problem;
s = socket(AF_UNIX, SOCK_STREAM, 0);
if (s == -1)
err(1, "Bad socket");
if (bind(s, (struct sockaddr *)sun, sizeof(*sun)) != 0)
err(1, "bind");
if (listen(s, 5) != 0) {
int saved_errno = errno;
unlink(path);
rmdir(dir);
errc(1, saved_errno, "listen");
}
fd = accept(s, (struct sockaddr *)&client_addr, &client_len);
if (fd == -1) {
int saved_errno = errno;
unlink(path);
rmdir(dir);
errc(1, saved_errno, "accept");
}
problem = check_id(fd);
if (problem) {
unlink(path);
rmdir(dir);
errx(1, "%s", problem);
}
unlink(path);
rmdir(dir);
}
int
main()
{
pid_t pid;
struct sockaddr_un sun;
char dir_template[] = "/tmp/peer.XXXXXX";
dir = mkdtemp(dir_template);
if (!dir)
err(1, "mkdtemp");
snprintf(path, sizeof path, "%s/%s", dir, "socket");
memset(&sun, 0, sizeof(struct sockaddr_un));
if (strlcpy(sun.sun_path, path, sizeof(sun.sun_path)) >=
sizeof(sun.sun_path))
errx(1, "Memory error");
sun.sun_family = AF_UNIX;
/* let's make those two rendez-vous, a bit artificial */
pid = fork();
if (pid == -1)
err(1, "can't fork");
if (pid == 0) {
client(&sun);
exit(0);
} else {
int status;
server(&sun);
waitpid(pid, &status, 0);
if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
printf("getpeereid test okay\n");
exit(0);
} else
errx(1, "Problem with child\n");
}
}
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