- Change all strcpy() calls to strncpy() to avoid buffer overflow potential - Add ICMP host unreachable support - Logging to syslog if log_file = "syslog:facility" - Now requires libcli 1.5 - All configuration moves to a config structure - Ability to modify and write config on the fly through command-line interface - Config file support is removed, and now handled by the cli - Show hostname in cli prompt - Keep current state type for tunnels - Add uptime command do CLI, which also shows real-time bandwidth utilisation - Add goodbye command to cluster master, which forces droppping a slave - Cache IP address allocation, so that reconnecting users get the same address - Fix tunnel resend timeouts, so that dead tunnels will be cleaned up - Allocate tunnels and radius without using a linked list which had issues - Fix some off-by-one errors in tunnel and session and radius arrays - Save and reload ip address pool when dieing - Check version and size of reloaded data when restarting - Remove plugin_config support - Remove old support for TBF which didn't work anyway. HTB is required to do throttling now. - Add COPYING and Changes files
86 lines
2 KiB
C
86 lines
2 KiB
C
#include <arpa/inet.h>
|
|
#include <netdb.h>
|
|
#include <netinet/in.h>
|
|
#include <linux/ip.h>
|
|
#include <linux/icmp.h>
|
|
#include <stdio.h>
|
|
#include <sys/socket.h>
|
|
#include <unistd.h>
|
|
#include <sys/types.h>
|
|
#include <sys/wait.h>
|
|
#include <memory.h>
|
|
#include "l2tpns.h"
|
|
|
|
extern ipt myip;
|
|
|
|
__u16 _checksum(unsigned char *addr, int count);
|
|
|
|
void host_unreachable(ipt destination, u16 id, ipt source, char *packet, int packet_len)
|
|
{
|
|
char buf[128] = {0};
|
|
struct iphdr *iph;
|
|
struct icmphdr *icmp;
|
|
char *data;
|
|
int len = 0, on = 1, icmp_socket;
|
|
struct sockaddr_in whereto = {0};
|
|
|
|
if (!(icmp_socket = socket(AF_INET, SOCK_RAW, IPPROTO_RAW)))
|
|
return;
|
|
setsockopt(icmp_socket, IPPROTO_IP, IP_HDRINCL, (char *)&on, sizeof(on));
|
|
|
|
whereto.sin_addr.s_addr = destination;
|
|
whereto.sin_family = AF_INET;
|
|
|
|
iph = (struct iphdr *)(buf);
|
|
len = sizeof(struct iphdr);
|
|
icmp = (struct icmphdr *)(buf + len);
|
|
len += sizeof(struct icmphdr);
|
|
data = (char *)(buf + len);
|
|
len += (packet_len < 64) ? packet_len : 64;
|
|
memcpy(data, packet, (packet_len < 64) ? packet_len : 64);
|
|
|
|
iph->tos = 0;
|
|
iph->id = id;
|
|
iph->frag_off = 0;
|
|
iph->ttl = 30;
|
|
iph->check = 0;
|
|
iph->version = 4;
|
|
iph->ihl = 5;
|
|
iph->protocol = 1;
|
|
iph->check = 0;
|
|
iph->daddr = destination;
|
|
iph->saddr = source;
|
|
|
|
iph->tot_len = ntohs(len);
|
|
|
|
icmp->type = ICMP_DEST_UNREACH;
|
|
icmp->code = ICMP_HOST_UNREACH;
|
|
icmp->checksum = _checksum((char *)icmp, sizeof(struct icmphdr) + ((packet_len < 64) ? packet_len : 64));
|
|
|
|
iph->check = _checksum((char *)iph, sizeof(struct iphdr));
|
|
|
|
sendto(icmp_socket, (char *)buf, len, 0, (struct sockaddr *)&whereto, sizeof(struct sockaddr));
|
|
close(icmp_socket);
|
|
}
|
|
|
|
__u16 _checksum(unsigned char *addr, int count)
|
|
{
|
|
register long sum = 0;
|
|
|
|
for (; count > 1; count -= 2)
|
|
{
|
|
sum += ntohs(*(u32 *)addr);
|
|
addr += 2;
|
|
}
|
|
|
|
if (count > 1) sum += *(unsigned char *)addr;
|
|
|
|
// take only 16 bits out of the 32 bit sum and add up the carries
|
|
while (sum >> 16)
|
|
sum = (sum & 0xFFFF) + (sum >> 16);
|
|
|
|
// one's complement the result
|
|
sum = ~sum;
|
|
|
|
return htons((u16) sum);
|
|
}
|