xref: /freebsd/tests/sys/capsicum/smoketest.c (revision 3fdbd8a07a2dcb8fe3cec19fc59ef064453e4755)
1 /* Small standalone test program to check the existence of Capsicum syscalls */
2 #include <sys/types.h>
3 #include <sys/stat.h>
4 #include <sys/wait.h>
5 #include <fcntl.h>
6 #include <unistd.h>
7 #include <sys/syscall.h>
8 #include <stdio.h>
9 #include <string.h>
10 #include <errno.h>
11 #include <stdlib.h>
12 #include <signal.h>
13 
14 #include "capsicum.h"
15 
16 static int seen_sigchld = 0;
17 static void handle_signal(int x) {
18   fprintf(stderr, "[%d] received SIGCHLD\n", getpid());
19   seen_sigchld = 1;
20 }
21 
22 int main(int argc, char *argv[]) {
23   signal(SIGCHLD, handle_signal);
24   int lifetime = 4; /* seconds */
25   if (1 < argc) {
26     lifetime = atoi(argv[1]);
27   }
28 
29   /* cap_rights_limit() available? */
30   cap_rights_t r_rws;
31   cap_rights_init(&r_rws, CAP_READ, CAP_WRITE, CAP_SEEK);
32   int cap_fd = dup(STDOUT_FILENO);
33   int rc = cap_rights_limit(cap_fd, &r_rws);
34   fprintf(stderr, "[%d] cap_fd=%d\n", getpid(), cap_fd);
35   if (rc < 0) fprintf(stderr, "*** cap_rights_limit() failed: errno=%d %s\n", errno, strerror(errno));
36 
37   /* cap_rights_get() available? */
38   cap_rights_t rights;
39   cap_rights_init(&rights, 0);
40   rc = cap_rights_get(cap_fd, &rights);
41   char buffer[256];
42   cap_rights_describe(&rights, buffer);
43   fprintf(stderr, "[%d] cap_rights_get(cap_fd=%d) rc=%d rights=%s\n", getpid(), cap_fd, rc, buffer);
44   if (rc < 0) fprintf(stderr, "*** cap_rights_get() failed: errno=%d %s\n", errno, strerror(errno));
45 
46   /* fstat() policed? */
47   struct stat buf;
48   rc = fstat(cap_fd, &buf);
49   fprintf(stderr, "[%d] fstat(cap_fd=%d) rc=%d errno=%d\n", getpid(), cap_fd, rc, errno);
50   if (rc != -1) fprintf(stderr, "*** fstat() unexpectedly succeeded\n");
51 
52   /* pdfork() available? */
53   int pd = -1;
54   rc = pdfork(&pd, 0);
55   if (rc < 0) fprintf(stderr, "*** pdfork() failed: errno=%d %s\n", errno, strerror(errno));
56 
57   if (rc == 0) { /* child */
58     int count = 0;
59     while (count < 20) {
60       fprintf(stderr, "  [%d] child alive, parent is ppid=%d\n", getpid(), getppid());
61       sleep(1);
62     }
63     fprintf(stderr, "  [%d] child exit(0)\n", getpid());
64     exit(0);
65   }
66   fprintf(stderr, "[%d] pdfork() rc=%d pd=%d\n", getpid(), rc, pd);
67 
68   /* pdgetpid() available? */
69   pid_t actual_pid = rc;
70   pid_t got_pid = -1;
71   rc = pdgetpid(pd, &got_pid);
72   if (rc < 0) fprintf(stderr, "*** pdgetpid(pd=%d) failed: errno=%d %s\n", pd, errno, strerror(errno));
73   fprintf(stderr, "[%d] pdgetpid(pd=%d)=%d, pdfork returned %d\n", getpid(), pd, got_pid, actual_pid);
74 
75   sleep(lifetime);
76 
77   /* pdkill() available? */
78   rc = pdkill(pd, SIGKILL);
79   fprintf(stderr, "[%d] pdkill(pd=%d, SIGKILL) -> rc=%d\n", getpid(), pd, rc);
80   if (rc < 0) fprintf(stderr, "*** pdkill() failed: errno=%d %s\n", errno, strerror(errno));
81   usleep(50000);  /* Allow time for death and signals */
82 
83   /* Death of a pdforked child should be invisible */
84   if (seen_sigchld) fprintf(stderr, "*** SIGCHLD emitted\n");
85   int status;
86   rc = wait4(-1, &status, WNOHANG, NULL);
87   if (rc > 0) fprintf(stderr, "*** wait4(-1, ...) unexpectedly found child %d\n", rc);
88 
89   fprintf(stderr, "[%d] forking off a child process to check cap_enter()\n", getpid());
90   pid_t child = fork();
91   if (child == 0) { /* child */
92     /* cap_getmode() / cap_enter() available? */
93     unsigned int cap_mode = -1;
94     rc = cap_getmode(&cap_mode);
95     fprintf(stderr, "  [%d] cap_getmode() -> rc=%d, cap_mode=%d\n", getpid(), rc, cap_mode);
96     if (rc < 0) fprintf(stderr, "*** cap_getmode() failed: errno=%d %s\n", errno, strerror(errno));
97 
98     rc = cap_enter();
99     fprintf(stderr, "  [%d] cap_enter() -> rc=%d\n", getpid(), rc);
100     if (rc < 0) fprintf(stderr, "*** cap_enter() failed: errno=%d %s\n", errno, strerror(errno));
101 
102     rc = cap_getmode(&cap_mode);
103     fprintf(stderr, "  [%d] cap_getmode() -> rc=%d, cap_mode=%d\n", getpid(), rc, cap_mode);
104     if (rc < 0) fprintf(stderr, "*** cap_getmode() failed: errno=%d %s\n", errno, strerror(errno));
105 
106     /* open disallowed? */
107     rc = open("/etc/passwd", O_RDONLY);
108     fprintf(stderr, "  [%d] open('/etc/passwd') -> rc=%d, errno=%d\n", getpid(), rc, errno);
109     if (rc != -1) fprintf(stderr, "*** open() unexpectedly succeeded\n");
110     if (errno != ECAPMODE) fprintf(stderr, "*** open() failed with errno %d not ECAPMODE\n", errno);
111     exit(0);
112   }
113   rc = wait4(child, &status, 0, NULL);
114   fprintf(stderr, "[%d] child %d exited with status %x\n", getpid(), child, status);
115 
116   /* fexecve() available? */
117   char* argv_pass[] = {(char*)"/bin/ls", "-l", "smoketest", NULL};
118   char* null_envp[] = {NULL};
119   int ls_bin = open("/bin/ls", O_RDONLY);
120   fprintf(stderr, "[%d] about to fexecve('/bin/ls', '-l', 'smoketest')\n", getpid());
121   rc = fexecve(ls_bin, argv_pass, null_envp);
122   /* should never reach here */
123   fprintf(stderr, "*** fexecve(fd=%d) failed: rc=%d errno=%d %s\n", ls_bin, rc, errno, strerror(errno));
124 
125   return 0;
126 }
127