First netlink functions.

Signed-off-by: Benjamin Cama <benoar@dolka.fr>
This commit is contained in:
Benjamin Cama 2011-08-14 22:56:35 +02:00
parent e57e8c3825
commit c7b02a0927

View file

@ -39,6 +39,7 @@ char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.176 2011/01/20 12:48:40 bodea Exp
#include <sched.h> #include <sched.h>
#include <sys/sysinfo.h> #include <sys/sysinfo.h>
#include <libcli.h> #include <libcli.h>
#include <linux/netlink.h>
#include "md5.h" #include "md5.h"
#include "l2tpns.h" #include "l2tpns.h"
@ -56,6 +57,7 @@ char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.176 2011/01/20 12:48:40 bodea Exp
// Globals // Globals
configt *config = NULL; // all configuration configt *config = NULL; // all configuration
int nlfd = -1; // netlink socket
int tunfd = -1; // tun interface file handle. (network device) int tunfd = -1; // tun interface file handle. (network device)
int udpfd = -1; // UDP file handle int udpfd = -1; // UDP file handle
int controlfd = -1; // Control signal handle int controlfd = -1; // Control signal handle
@ -71,6 +73,7 @@ int epollfd = -1; // event polling
time_t basetime = 0; // base clock time_t basetime = 0; // base clock
char hostname[1000] = ""; // us. char hostname[1000] = ""; // us.
static int tunidx; // ifr_ifindex of tun device static int tunidx; // ifr_ifindex of tun device
int nlseqnum = 0; // netlink sequence number
static int syslog_log = 0; // are we logging to syslog static int syslog_log = 0; // are we logging to syslog
static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog). static FILE *log_stream = 0; // file handle for direct logging (i.e. direct into file, not via syslog).
uint32_t last_id = 0; // Unique ID for radius accounting uint32_t last_id = 0; // Unique ID for radius accounting
@ -514,6 +517,79 @@ void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
return; return;
} }
//
// Set up netlink socket
static void initnetlink(void)
{
struct sockaddr_nl nladdr;
nlfd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
if (nlfd < 0)
return; // don't use netlink
memset(&nladdr, 0, sizeof(nladdr));
nladdr.nl_family = AF_NETLINK;
nladdr.nl_pid = getpid();
if (bind(fd, (struct sockaddr *)&nladdr, sizeof(nladdr)) < 0)
{
close(fd);
fd = -1;
return; // don't use netlink
}
}
static ssize_t netlink_send(struct nlmsghdr *nh)
{
struct sockaddr_nl nladdr;
struct iovec iov;
struct msghdr msg;
ssize_t len;
char buf[4096];
struct nlmsghdr *ack_nh;
nh->nlmsg_pid = getpid();
nh->nlmsg_seq = ++nlseqnum;
nh->nlmsg_flags |= NLM_F_ACK;
iov = { (void *)nh, nh->msg_len };
// set kernel address
memset(nladdr, 0, sizeof(nladdr));
nladdr.nl_family = AF_NETLINK;
msg = { (void *)&nladdr, sizeof(nladdr), &iov, 1, NULL, 0, 0 };
if ((len = sendmsg(nlfd, &msg, 0)) < 0)
return len; // return error code
// expect ack
iov = { buf, sizeof(buf) };
msg = { (void *)&nladdr, sizeof(nladdr), &iov, 1, NULL, 0, 0 };
if ((len = recvmsg(nlfd, &msg, 0)) < 0)
return len; // return error code
for (ack_nh = (struct nlmsghdr *)buf; NLMSG_OK (ack_nh, len);
ack_nh = NLMSG_NEXT (ack_nh, len))
{
if (ack_nh->nlmsg_type == NLMSG_DONE)
return 1; // didn't get the ack
if (ack_nh->nlmsg_type == NLMSG_ERROR)
{
struct nlmsgerr *errmsg = NLMSG_DATA(ack_nh);
if (errmsg->error)
return errmsg->error; // got an error back
if (errmsg->msg.nlmsg_seq == nh->nlmsg_seq)
return 0; // ack received
else
return 2; // wrong seq number?!
}
// unknown message
LOG(3, 0, 0, "Got an unknown netlink message: type %d\n", ack_nh->nlmsg_type);
}
return 3; // no end message?!
}
// defined in linux/ipv6.h, but tricky to include from user-space // defined in linux/ipv6.h, but tricky to include from user-space
// TODO: move routing to use netlink rather than ioctl // TODO: move routing to use netlink rather than ioctl
struct in6_ifreq { struct in6_ifreq {
@ -549,6 +625,14 @@ static void inittun(void)
} }
assert(strlen(ifr.ifr_name) < sizeof(config->tundevice)); assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1); strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
{
struct nlmsghdr nlh;
{
LOG(0, 0, 0, "Error setting up tun device: %s", strerror(errno));
exit(1);
}
}
ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP); ifrfd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
sin.sin_family = AF_INET; sin.sin_family = AF_INET;