blob: 7d41b0b71386c5ef760e5ad6c92e63408b6d996d [file] [log] [blame]
#include <assert.h>
#include <string.h>
#include <unistd.h>
#include <netinet/in.h>
#include <linux/netlink.h>
#include <linux/sock_diag.h>
#include <linux/inet_diag.h>
static int
send_query(const int fd, const int family, const int proto)
{
struct sockaddr_nl nladdr = {
.nl_family = AF_NETLINK
};
struct {
struct nlmsghdr nlh;
struct inet_diag_req_v2 idr;
} req = {
.nlh = {
.nlmsg_len = sizeof(req),
.nlmsg_type = SOCK_DIAG_BY_FAMILY,
.nlmsg_flags = NLM_F_DUMP | NLM_F_REQUEST
},
.idr = {
.sdiag_family = family,
.sdiag_protocol = proto,
.idiag_states = -1
}
};
struct iovec iov = {
.iov_base = &req,
.iov_len = sizeof(req)
};
struct msghdr msg = {
.msg_name = (void*)&nladdr,
.msg_namelen = sizeof(nladdr),
.msg_iov = &iov,
.msg_iovlen = 1
};
return sendmsg(fd, &msg, 0) > 0;
}
static int
check_responses(const int fd)
{
static char buf[8192];
struct sockaddr_nl nladdr = {
.nl_family = AF_NETLINK
};
struct iovec iov = {
.iov_base = buf,
.iov_len = sizeof(buf)
};
struct msghdr msg = {
.msg_name = (void*)&nladdr,
.msg_namelen = sizeof(nladdr),
.msg_iov = &iov,
.msg_iovlen = 1
};
ssize_t ret = recvmsg(fd, &msg, 0);
if (ret <= 0)
return 0;
struct nlmsghdr *h = (struct nlmsghdr*)buf;
return (NLMSG_OK(h, ret) &&
h->nlmsg_type != NLMSG_ERROR &&
h->nlmsg_type != NLMSG_DONE) ? 1 : 0;
}
int main(void)
{
struct sockaddr_in addr;
socklen_t len = sizeof(addr);
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
close(0);
close(1);
assert(socket(PF_INET, SOCK_STREAM, 0) == 0);
assert(bind(0, (struct sockaddr *) &addr, len) == 0);
assert(listen(0, 5) == 0);
if (socket(AF_NETLINK, SOCK_RAW, NETLINK_INET_DIAG) != 1)
return 77;
return (send_query(1, AF_INET, IPPROTO_TCP) &&
check_responses(1)) ? 0 : 77;
}