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#include <sys/capsicum.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <err.h>
#include <sys/ioccom.h>
#include <net/bpf.h>
int main(void)
{
u_int mode;
if (-1 == cap_getmode(&mode)) {
perror("cap_getmode() failed:");
exit(1);
} else {
assert(mode == 0U);
}
// example from man cap_rights_get
cap_rights_t setrights, getrights;
int fd;
memset(&setrights, 0, sizeof(setrights));
memset(&getrights, 0, sizeof(getrights));
fd = open("capsicum.c", O_RDONLY);
if (fd < 0)
err(1, "open() failed");
cap_rights_init(&setrights, CAP_IOCTL, CAP_FSTAT, CAP_READ);
if (cap_rights_limit(fd, &setrights) < 0 && errno != ENOSYS)
err(1, "cap_rights_limit() failed");
unsigned long cmds[] = { BIOCGSTATS, BIOCROTZBUF };
if (cap_ioctls_limit(fd, cmds, sizeof(cmds) / sizeof(cmds[0])) < 0 && errno != ENOSYS) {
err(1, "cap_ioctls_limit() filed");
}
uint32_t fcntlrights = CAP_FCNTL_GETFL | CAP_FCNTL_SETFL;
if (cap_fcntls_limit(STDIN_FILENO, fcntlrights) < 0 && errno != ENOSYS) {
err(1, "cap_fcnls_limit() filed");
}
if (cap_rights_get(fd, &getrights) < 0 && errno != ENOSYS)
err(1, "cap_rights_get() failed");
assert(memcmp(&setrights, &getrights, sizeof(setrights)) == 0);
unsigned long getcmds[2];
if (cap_ioctls_get(fd, getcmds, 2) < 0 && errno != ENOSYS)
err(1, "cap_ioctls_get() failed");
assert(memcmp(cmds, getcmds, sizeof(cmds)) == 0);
uint32_t getfcntlrights;
if (cap_fcntls_get(STDIN_FILENO, &getfcntlrights) < 0 && errno != ENOSYS) {
err(1, "cap_fcnls_limit() filed");
}
assert(fcntlrights == getfcntlrights);
//close(fd);
cap_enter();
if (-1 == cap_getmode(&mode)) {
perror("cap_getmode() failed:");
exit(1);
} else {
assert(mode != 0U);
}
// error section
int *px = malloc(sizeof(int));
int x = px[0];
cap_getmode(NULL);
cap_rights_get(0, NULL);
cap_rights_get(x, &getrights);
cap_rights_t* badrights = malloc(sizeof(cap_rights_t));
cap_rights_init(badrights, CAP_FSTAT, CAP_READ);
free(badrights);
cap_rights_get(0, badrights);
cap_rights_limit(x, &setrights);
cap_rights_limit(fd, badrights);
int fd2 = open("foo", O_RDWR);
if (fd2 >= 0)
err(1, "open in write mode should have failed");
}
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