#ifndef __APPLE__
#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <unistd.h>
#include "debug.h"
#include "seccomp.h"
union cmsg {
char buf[CMSG_SPACE(sizeof(int))];
struct cmsghdr hdr;
};
void seccomp_socket_create(int *sock) {
int tmp_sock[2] = {-1, -1};
if (socketpair(AF_UNIX, SOCK_STREAM, 0, tmp_sock) < 0) {
FATAL("socketpair");
}
if (dup2(tmp_sock[STDIN_FILENO], SECCOMP_SOCKET_RECV_FD) < 0) {
FATAL("seccomp_socket_create - dup2 (1)");
}
if (dup2(tmp_sock[STDOUT_FILENO], SECCOMP_SOCKET_SEND_FD) < 0) {
FATAL("seccomp_socket_create - dup2 (1)");
}
if (close(tmp_sock[STDIN_FILENO]) < 0) {
FATAL("seccomp_socket_create - close (1)");
}
if (close(tmp_sock[STDOUT_FILENO]) < 0) {
FATAL("seccomp_socket_create - close (2)");
}
sock[STDIN_FILENO] = SECCOMP_SOCKET_RECV_FD;
sock[STDOUT_FILENO] = SECCOMP_SOCKET_SEND_FD;
}
void seccomp_socket_send(int sockfd, int fd) {
int data = 12345;
struct iovec iov = {.iov_base = &data, .iov_len = sizeof(data)};
union cmsg control_msg = {.hdr = {
.cmsg_len = CMSG_LEN(sizeof(int)),
.cmsg_level = SOL_SOCKET,
.cmsg_type = SCM_RIGHTS,
}};
struct msghdr message = {.msg_control = control_msg.buf,
.msg_controllen = sizeof(control_msg.buf),
.msg_flags = 0,
.msg_iov = &iov,
.msg_iovlen = 1,
.msg_name = NULL,
.msg_namelen = 0};
memcpy(CMSG_DATA(&control_msg.hdr), &fd, sizeof(int));
if (sendmsg(sockfd, &message, 0) == -1) { FATAL("sendmsg"); }
}
int seccomp_socket_recv(int sockfd) {
int data;
struct iovec iov = {.iov_base = &data, .iov_len = sizeof(data)};
union cmsg control_msg = {0};
struct msghdr message = {.msg_control = control_msg.buf,
.msg_controllen = sizeof(control_msg.buf),
.msg_flags = 0,
.msg_iov = &iov,
.msg_iovlen = 1,
.msg_name = NULL,
.msg_namelen = 0};
int fd;
if (recvmsg(sockfd, &message, 0) < 0) { FATAL("recvmsg"); }
if (control_msg.hdr.cmsg_len != CMSG_LEN(sizeof(int))) {
FATAL("control_msg.hdr.cmsg_len");
}
if (control_msg.hdr.cmsg_level != SOL_SOCKET) {
FATAL("control_msg.hdr.cmsg_level");
}
if (control_msg.hdr.cmsg_type != SCM_RIGHTS) {
FATAL("control_msg.hdr.cmsg_type");
}
memcpy(&fd, CMSG_DATA(&control_msg.hdr), sizeof(int));
return fd;
}
#endif
