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/* Small standalone test program to check the existence of Capsicum syscalls */
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <signal.h>
#include "capsicum.h"
static int seen_sigchld = 0;
static void handle_signal(int x) {
fprintf(stderr, "[%d] received SIGCHLD\n", getpid());
seen_sigchld = 1;
}
int main(int argc, char *argv[]) {
signal(SIGCHLD, handle_signal);
int lifetime = 4; /* seconds */
if (1 < argc) {
lifetime = atoi(argv[1]);
}
/* cap_rights_limit() available? */
cap_rights_t r_rws;
cap_rights_init(&r_rws, CAP_READ, CAP_WRITE, CAP_SEEK);
int cap_fd = dup(STDOUT_FILENO);
int rc = cap_rights_limit(cap_fd, &r_rws);
fprintf(stderr, "[%d] cap_fd=%d\n", getpid(), cap_fd);
if (rc < 0) fprintf(stderr, "*** cap_rights_limit() failed: errno=%d %s\n", errno, strerror(errno));
/* cap_rights_get() available? */
cap_rights_t rights;
cap_rights_init(&rights, 0);
rc = cap_rights_get(cap_fd, &rights);
char buffer[256];
cap_rights_describe(&rights, buffer);
fprintf(stderr, "[%d] cap_rights_get(cap_fd=%d) rc=%d rights=%s\n", getpid(), cap_fd, rc, buffer);
if (rc < 0) fprintf(stderr, "*** cap_rights_get() failed: errno=%d %s\n", errno, strerror(errno));
/* fstat() policed? */
struct stat buf;
rc = fstat(cap_fd, &buf);
fprintf(stderr, "[%d] fstat(cap_fd=%d) rc=%d errno=%d\n", getpid(), cap_fd, rc, errno);
if (rc != -1) fprintf(stderr, "*** fstat() unexpectedly succeeded\n");
/* pdfork() available? */
int pd = -1;
rc = pdfork(&pd, 0);
if (rc < 0) fprintf(stderr, "*** pdfork() failed: errno=%d %s\n", errno, strerror(errno));
if (rc == 0) { /* child */
int count = 0;
while (count < 20) {
fprintf(stderr, " [%d] child alive, parent is ppid=%d\n", getpid(), getppid());
sleep(1);
}
fprintf(stderr, " [%d] child exit(0)\n", getpid());
exit(0);
}
fprintf(stderr, "[%d] pdfork() rc=%d pd=%d\n", getpid(), rc, pd);
/* pdgetpid() available? */
pid_t actual_pid = rc;
pid_t got_pid = -1;
rc = pdgetpid(pd, &got_pid);
if (rc < 0) fprintf(stderr, "*** pdgetpid(pd=%d) failed: errno=%d %s\n", pd, errno, strerror(errno));
fprintf(stderr, "[%d] pdgetpid(pd=%d)=%d, pdfork returned %d\n", getpid(), pd, got_pid, actual_pid);
sleep(lifetime);
/* pdkill() available? */
rc = pdkill(pd, SIGKILL);
fprintf(stderr, "[%d] pdkill(pd=%d, SIGKILL) -> rc=%d\n", getpid(), pd, rc);
if (rc < 0) fprintf(stderr, "*** pdkill() failed: errno=%d %s\n", errno, strerror(errno));
usleep(50000); /* Allow time for death and signals */
/* Death of a pdforked child should be invisible */
if (seen_sigchld) fprintf(stderr, "*** SIGCHLD emitted\n");
int status;
rc = wait4(-1, &status, WNOHANG, NULL);
if (rc > 0) fprintf(stderr, "*** wait4(-1, ...) unexpectedly found child %d\n", rc);
fprintf(stderr, "[%d] forking off a child process to check cap_enter()\n", getpid());
pid_t child = fork();
if (child == 0) { /* child */
/* cap_getmode() / cap_enter() available? */
unsigned int cap_mode = -1;
rc = cap_getmode(&cap_mode);
fprintf(stderr, " [%d] cap_getmode() -> rc=%d, cap_mode=%d\n", getpid(), rc, cap_mode);
if (rc < 0) fprintf(stderr, "*** cap_getmode() failed: errno=%d %s\n", errno, strerror(errno));
rc = cap_enter();
fprintf(stderr, " [%d] cap_enter() -> rc=%d\n", getpid(), rc);
if (rc < 0) fprintf(stderr, "*** cap_enter() failed: errno=%d %s\n", errno, strerror(errno));
rc = cap_getmode(&cap_mode);
fprintf(stderr, " [%d] cap_getmode() -> rc=%d, cap_mode=%d\n", getpid(), rc, cap_mode);
if (rc < 0) fprintf(stderr, "*** cap_getmode() failed: errno=%d %s\n", errno, strerror(errno));
/* open disallowed? */
rc = open("/etc/passwd", O_RDONLY);
fprintf(stderr, " [%d] open('/etc/passwd') -> rc=%d, errno=%d\n", getpid(), rc, errno);
if (rc != -1) fprintf(stderr, "*** open() unexpectedly succeeded\n");
if (errno != ECAPMODE) fprintf(stderr, "*** open() failed with errno %d not ECAPMODE\n", errno);
exit(0);
}
rc = wait4(child, &status, 0, NULL);
fprintf(stderr, "[%d] child %d exited with status %x\n", getpid(), child, status);
/* fexecve() available? */
char* argv_pass[] = {(char*)"/bin/ls", "-l", "smoketest", NULL};
char* null_envp[] = {NULL};
int ls_bin = open("/bin/ls", O_RDONLY);
fprintf(stderr, "[%d] about to fexecve('/bin/ls', '-l', 'smoketest')\n", getpid());
rc = fexecve(ls_bin, argv_pass, null_envp);
/* should never reach here */
fprintf(stderr, "*** fexecve(fd=%d) failed: rc=%d errno=%d %s\n", ls_bin, rc, errno, strerror(errno));
return 0;
}
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