static int
rmnet_map_ipv6_dl_csum_trailer(struct sk_buff *skb,
struct rmnet_map_dl_csum_trailer *csum_trailer)
{
__sum16 *csum_field, ip6_payload_csum, pseudo_csum, csum_temp;
u16 csum_value, csum_value_final;
__be16 ip6_hdr_csum, addend;
struct ipv6hdr *ip6h;
void *txporthdr;
u32 length;
ip6h = (struct ipv6hdr *)(skb->data);
txporthdr = skb->data + sizeof(struct ipv6hdr);
csum_field = rmnet_map_get_csum_field(ip6h->nexthdr, txporthdr);
if (!csum_field)
return -EPROTONOSUPPORT;
csum_value = ~ntohs(csum_trailer->csum_value);
ip6_hdr_csum = (__force __be16)
~ntohs((__force __be16)ip_compute_csum(ip6h,
(int)(txporthdr - (void *)(skb->data))));
ip6_payload_csum = csum16_sub((__force __sum16)csum_value,
ip6_hdr_csum);
length = (ip6h->nexthdr == IPPROTO_UDP) ?
ntohs(((struct udphdr *)txporthdr)->len) :
ntohs(ip6h->payload_len);
pseudo_csum = ~(csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
length, ip6h->nexthdr, 0));
addend = (__force __be16)ntohs((__force __be16)pseudo_csum);
pseudo_csum = csum16_add(ip6_payload_csum, addend);
addend = (__force __be16)ntohs((__force __be16)*csum_field);
csum_temp = ~csum16_sub(pseudo_csum, addend);
csum_value_final = (__force u16)csum_temp;
if (unlikely(csum_value_final == 0)) {
switch (ip6h->nexthdr) {
case IPPROTO_UDP:
/* RFC 2460 section 8.1
* DL6 One's complement rule for UDP checksum 0
*/
csum_value_final = ~csum_value_final;
break;
case IPPROTO_TCP:
/* DL6 Non-RFC compliant TCP checksum found */
if (*csum_field == (__force __sum16)0xFFFF)
csum_value_final = ~csum_value_final;
break;
}
}
if (csum_value_final == ntohs((__force __be16)*csum_field))
return 0;
else
return -EINVAL;
}
static void igmp_send_report(struct device *dev, unsigned long address, int type)
{
struct sk_buff *skb=alloc_skb(MAX_IGMP_SIZE, GFP_ATOMIC);
int tmp;
struct igmphdr *ih;
if(skb==NULL)
return;
if (type != IGMP_HOST_LEAVE_MESSAGE)
tmp=ip_build_header(skb, dev->pa_addr, address, &dev, IPPROTO_IGMP, NULL,
28 , 0, 1, NULL);
else
tmp=ip_build_header(skb, dev->pa_addr, IGMP_ALL_ROUTER, &dev, IPPROTO_IGMP, NULL,
28, 0, 1, NULL);
if(tmp<0)
{
kfree_skb(skb, FREE_WRITE);
return;
}
ih=(struct igmphdr *)skb_put(skb,sizeof(struct igmphdr));
ih->type=type;
ih->code=0;
ih->csum=0;
ih->group=address;
ih->csum=ip_compute_csum((void *)ih,sizeof(struct igmphdr)); /* Checksum fill */
ip_queue_xmit(NULL,dev,skb,1);
}
static int igmp_send_report(struct device *dev, u32 group, int type)
{
struct sk_buff *skb;
struct iphdr *iph;
struct igmphdr *ih;
struct rtable *rt;
u32 dst;
/* According to IGMPv2 specs, LEAVE messages are
* sent to all-routers group.
*/
dst = group;
if (type == IGMP_HOST_LEAVE_MESSAGE)
dst = IGMP_ALL_ROUTER;
if (ip_route_output(&rt, dst, 0, 0, dev->ifindex))
return -1;
if (rt->rt_src == 0) {
ip_rt_put(rt);
return -1;
}
skb=alloc_skb(IGMP_SIZE+dev->hard_header_len+15, GFP_ATOMIC);
if (skb == NULL) {
ip_rt_put(rt);
return -1;
}
skb->dst = &rt->u.dst;
skb_reserve(skb, (dev->hard_header_len+15)&~15);
skb->nh.iph = iph = (struct iphdr *)skb_put(skb, sizeof(struct iphdr)+4);
iph->version = 4;
iph->ihl = (sizeof(struct iphdr)+4)>>2;
iph->tos = 0;
iph->frag_off = 0;
iph->ttl = 1;
iph->daddr = dst;
iph->saddr = rt->rt_src;
iph->protocol = IPPROTO_IGMP;
iph->tot_len = htons(IGMP_SIZE);
iph->id = htons(ip_id_count++);
((u8*)&iph[1])[0] = IPOPT_RA;
((u8*)&iph[1])[1] = 4;
((u8*)&iph[1])[2] = 0;
((u8*)&iph[1])[3] = 0;
ip_send_check(iph);
ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
ih->type=type;
ih->code=0;
ih->csum=0;
ih->group=group;
ih->csum=ip_compute_csum((void *)ih, sizeof(struct igmphdr));
return skb->dst->output(skb);
}
static int pim6_rcv(struct sk_buff *skb)
{
struct pimreghdr *pim;
struct ipv6hdr *encap;
struct net_device *reg_dev = NULL;
if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap)))
goto drop;
pim = (struct pimreghdr *)skb_transport_header(skb);
if (pim->type != ((PIM_VERSION << 4) | PIM_REGISTER) ||
(pim->flags & PIM_NULL_REGISTER) ||
(ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
csum_fold(skb_checksum(skb, 0, skb->len, 0))))
goto drop;
/* check if the inner packet is destined to mcast group */
encap = (struct ipv6hdr *)(skb_transport_header(skb) +
sizeof(*pim));
if (!ipv6_addr_is_multicast(&encap->daddr) ||
encap->payload_len == 0 ||
ntohs(encap->payload_len) + sizeof(*pim) > skb->len)
goto drop;
read_lock(&mrt_lock);
if (reg_vif_num >= 0)
reg_dev = vif6_table[reg_vif_num].dev;
if (reg_dev)
dev_hold(reg_dev);
read_unlock(&mrt_lock);
if (reg_dev == NULL)
goto drop;
skb->mac_header = skb->network_header;
skb_pull(skb, (u8 *)encap - skb->data);
skb_reset_network_header(skb);
skb->dev = reg_dev;
skb->protocol = htons(ETH_P_IP);
skb->ip_summed = 0;
skb->pkt_type = PACKET_HOST;
dst_release(skb->dst);
((struct net_device_stats *)netdev_priv(reg_dev))->rx_bytes += skb->len;
((struct net_device_stats *)netdev_priv(reg_dev))->rx_packets++;
skb->dst = NULL;
nf_reset(skb);
netif_rx(skb);
dev_put(reg_dev);
return 0;
drop:
kfree_skb(skb);
return 0;
}
int igmp_send_report_full(struct net_device *dev, u32 group, int type,
u8 respond, u32 dst)
{
struct sk_buff *skb;
struct iphdr *iph;
struct igmphdr *ih;
struct rtable *rt;
if (ip_route_output(&rt, dst, 0, 0, dev->ifindex))
return -1;
if (rt->rt_src == 0) {
ip_rt_put(rt);
return -1;
}
skb=alloc_skb(IGMP_SIZE+dev->hard_header_len+15, GFP_ATOMIC);
if (skb == NULL) {
ip_rt_put(rt);
return -1;
}
skb->dst = &rt->u.dst;
skb_reserve(skb, (dev->hard_header_len+15)&~15);
skb->nh.iph = iph = (struct iphdr *)skb_put(skb, sizeof(struct iphdr)+4);
iph->version = 4;
iph->ihl = (sizeof(struct iphdr)+4)>>2;
iph->tos = 0;
iph->frag_off = htons(IP_DF);
iph->ttl = 1;
iph->daddr = dst;
iph->saddr = rt->rt_src;
iph->protocol = IPPROTO_IGMP;
iph->tot_len = htons(IGMP_SIZE);
ip_select_ident(iph, &rt->u.dst, NULL);
((u8*)&iph[1])[0] = IPOPT_RA;
((u8*)&iph[1])[1] = 4;
((u8*)&iph[1])[2] = 0;
((u8*)&iph[1])[3] = 0;
ip_send_check(iph);
ih = (struct igmphdr *)skb_put(skb, sizeof(struct igmphdr));
ih->type=type;
ih->code=respond;
ih->csum=0;
ih->group=group;
ih->csum=ip_compute_csum((void *)ih, sizeof(struct igmphdr));
return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev,
output_maybe_reroute);
}
int icmp_rcv(struct sk_buff *skb, unsigned short len)
{
struct icmphdr *icmph = skb->h.icmph;
struct rtable *rt = (struct rtable*)skb->dst;
icmp_statistics.IcmpInMsgs++;
/*
* 18 is the highest 'known' ICMP type. Anything else is a mystery
*
* RFC 1122: 3.2.2 Unknown ICMP messages types MUST be silently discarded.
*/
if(len < sizeof(struct icmphdr) ||
ip_compute_csum((unsigned char *) icmph, len) ||
icmph->type > NR_ICMP_TYPES)
goto error;
/*
* Parse the ICMP message
*/
if (rt->rt_flags&(RTCF_BROADCAST|RTCF_MULTICAST)) {
/*
* RFC 1122: 3.2.2.6 An ICMP_ECHO to broadcast MAY be
* silently ignored (we let user decide with a sysctl).
* RFC 1122: 3.2.2.8 An ICMP_TIMESTAMP MAY be silently
* discarded if to broadcast/multicast.
*/
if (icmph->type == ICMP_ECHO &&
sysctl_icmp_echo_ignore_broadcasts) {
goto error;
}
if (icmph->type != ICMP_ECHO &&
icmph->type != ICMP_TIMESTAMP &&
icmph->type != ICMP_ADDRESS &&
icmph->type != ICMP_ADDRESSREPLY) {
goto error;
}
}
len -= sizeof(struct icmphdr);
(*icmp_pointers[icmph->type].input)++;
(icmp_pointers[icmph->type].handler)(icmph, skb, len);
drop:
kfree_skb(skb);
return 0;
error:
icmp_statistics.IcmpInErrors++;
goto drop;
}
int igmp_rcv(struct sk_buff *skb, struct device *dev, struct options *opt,
__u32 daddr, unsigned short len, __u32 saddr, int redo,
struct inet_protocol *protocol)
{
/* This basically follows the spec line by line -- see RFC1112 */
struct igmphdr *ih;
/*
* Mrouted needs to able to query local interfaces. So
* report for the device this was sent at. (Which can
* be the loopback this time)
*/
if(dev->flags&IFF_LOOPBACK)
{
dev=ip_dev_find(saddr);
if(dev==NULL)
dev=&loopback_dev;
}
ih=(struct igmphdr *)skb->h.raw;
if(len <sizeof(struct igmphdr) || skb->ip_hdr->ttl<1 || ip_compute_csum((void *)skb->h.raw,sizeof(struct igmphdr)))
{
kfree_skb(skb, FREE_READ);
return 0;
}
/*
* I have a report that someone does this!
*/
if(saddr==0)
{
printk(KERN_INFO "Broken multicast host using 0.0.0.0 heard on %s\n",
dev->name);
kfree_skb(skb, FREE_READ);
return 0;
}
if(ih->type==IGMP_HOST_MEMBERSHIP_QUERY && daddr==IGMP_ALL_HOSTS)
igmp_heard_query(dev,ih->code);
if(ih->type==IGMP_HOST_MEMBERSHIP_REPORT && daddr==ih->group)
igmp_heard_report(dev,ih->group, saddr);
if(ih->type==IGMP_HOST_NEW_MEMBERSHIP_REPORT && daddr==ih->group)
igmp_heard_report(dev,ih->group, saddr);
kfree_skb(skb, FREE_READ);
return 0;
}
int igmp_rcv(struct sk_buff *skb, struct device *dev, struct options *opt,
unsigned long daddr, unsigned short len, unsigned long saddr, int redo,
struct inet_protocol *protocol)
{
/* This basically follows the spec line by line -- see RFC1112 */
struct igmphdr *igh=(struct igmphdr *)skb->h.raw;
if(skb->ip_hdr->ttl!=1 || ip_compute_csum((void *)igh,sizeof(*igh)))
{
kfree_skb(skb, FREE_READ);
return 0;
}
if(igh->type==IGMP_HOST_MEMBERSHIP_QUERY && daddr==IGMP_ALL_HOSTS)
igmp_heard_query(dev);
if(igh->type==IGMP_HOST_MEMBERSHIP_REPORT && daddr==igh->group)
igmp_heard_report(dev,igh->group);
kfree_skb(skb, FREE_READ);
return 0;
}
int igmp_rcv(struct sk_buff *skb, unsigned short len)
{
/* This basically follows the spec line by line -- see RFC1112 */
struct igmphdr *ih = skb->h.igmph;
struct in_device *in_dev = skb->dev->ip_ptr;
if (len < sizeof(struct igmphdr) || ip_compute_csum((void *)ih, len)
|| in_dev==NULL) {
kfree_skb(skb);
return 0;
}
switch (ih->type) {
case IGMP_HOST_MEMBERSHIP_QUERY:
igmp_heard_query(in_dev, ih->code, ih->group);
break;
case IGMP_HOST_MEMBERSHIP_REPORT:
case IGMP_HOST_NEW_MEMBERSHIP_REPORT:
/* Is it our report looped back? */
if (((struct rtable*)skb->dst)->key.iif == 0)
break;
igmp_heard_report(in_dev, ih->group);
break;
case IGMP_PIM:
#ifdef CONFIG_IP_PIMSM_V1
return pim_rcv_v1(skb, len);
#endif
case IGMP_DVMRP:
case IGMP_TRACE:
case IGMP_HOST_LEAVE_MESSAGE:
case IGMP_MTRACE:
case IGMP_MTRACE_RESP:
break;
default:
NETDEBUG(printk(KERN_DEBUG "New IGMP type=%d, why we do not know about it?\n", ih->type));
}
kfree_skb(skb);
return 0;
}
static bool ipv4_validate_packet_len(struct sk_buff *skb_in, struct sk_buff *skb_out)
{
struct iphdr *ip4_hdr = ip_hdr(skb_out);
if (skb_out->len <= skb_out->dev->mtu)
return true;
if (ip4_hdr->protocol == IPPROTO_ICMP) {
struct icmphdr *icmp4_hdr = icmp_hdr(skb_out);
if (is_icmp4_error(icmp4_hdr->type)) {
int new_packet_len = skb_out->dev->mtu;
skb_trim(skb_out, new_packet_len);
ip4_hdr->tot_len = cpu_to_be16(new_packet_len);
ip4_hdr->check = 0;
ip4_hdr->check = ip_fast_csum(ip4_hdr, ip4_hdr->ihl);
icmp4_hdr->checksum = 0;
icmp4_hdr->checksum = ip_compute_csum(icmp4_hdr, new_packet_len - 4 * ip4_hdr->ihl);
return true;
}
}
if (is_dont_fragment_set(ip4_hdr)) {
unsigned int ipv6_mtu = skb_in->dev->mtu;
unsigned int ipv4_mtu = skb_out->dev->mtu;
log_debug("Packet is too large for the outgoing MTU and the DF flag is set. Dropping...");
icmpv6_send(skb_in, ICMPV6_PKT_TOOBIG, 0, cpu_to_be32(min_uint(ipv4_mtu, ipv6_mtu - 20)));
return false;
}
/* The kernel will fragment it. */
return true;
}
static void igmp_send_report(struct device *dev, unsigned long address, int type)
{
struct sk_buff *skb=alloc_skb(MAX_IGMP_SIZE, GFP_ATOMIC);
int tmp;
struct igmphdr *igh;
if(skb==NULL)
return;
tmp=ip_build_header(skb, INADDR_ANY, address, &dev, IPPROTO_IGMP, NULL,
skb->mem_len, 0, 1);
if(tmp<0)
{
kfree_skb(skb, FREE_WRITE);
return;
}
igh=(struct igmphdr *)(skb->data+tmp);
skb->len=tmp+sizeof(*igh);
igh->csum=0;
igh->unused=0;
igh->type=type;
igh->group=address;
igh->csum=ip_compute_csum((void *)igh,sizeof(*igh));
ip_queue_xmit(NULL,dev,skb,1);
}
__initfunc(int whitehole_init(struct device *dev))
{
dev->priv = kmalloc(sizeof(struct net_device_stats), GFP_KERNEL);
if (dev->priv == NULL)
return -ENOBUFS;
memset(dev->priv, 0, sizeof(struct net_device_stats));
dev->get_stats = whitehole_get_stats;
dev->hard_start_xmit = whitehole_xmit;
dev->open = whitehole_open;
dev->stop = whitehole_close;
ether_setup(dev);
dev->tx_queue_len = 0;
dev->flags |= IFF_NOARP;
dev->flags &= ~(IFF_BROADCAST|IFF_MULTICAST);
dev->iflink = 0;
whitehole_iph.ihl = 5;
whitehole_iph.version = 4;
whitehole_iph.ttl = 2;
whitehole_iph.saddr = in_aton("193.233.7.21");
whitehole_iph.daddr = in_aton("193.233.7.10");
whitehole_iph.tot_len = htons(20);
whitehole_iph.check = ip_compute_csum((void *)&whitehole_iph, 20);
return 0;
}
int icmp_rcv(struct sk_buff *skb, struct device *dev, struct options *opt,
__u32 daddr, unsigned short len,
__u32 saddr, int redo, struct inet_protocol *protocol)
{
struct icmphdr *icmph=(void *)skb->h.raw;
#ifdef CONFIG_IP_TRANSPARENT_PROXY
int r;
#endif
icmp_statistics.IcmpInMsgs++;
if(len < sizeof(struct icmphdr))
{
icmp_statistics.IcmpInErrors++;
NETDEBUG(printk(KERN_INFO "ICMP: runt packet\n"));
kfree_skb(skb, FREE_READ);
return 0;
}
/*
* Validate the packet
*/
if (ip_compute_csum((unsigned char *) icmph, len))
{
/* Failed checksum! */
icmp_statistics.IcmpInErrors++;
NETDEBUG(printk(KERN_INFO "ICMP: failed checksum from %s!\n", in_ntoa(saddr)));
kfree_skb(skb, FREE_READ);
return(0);
}
/*
* 18 is the highest 'known' ICMP type. Anything else is a mystery
*
* RFC 1122: 3.2.2 Unknown ICMP messages types MUST be silently discarded.
*/
if(icmph->type > 18)
{
icmp_statistics.IcmpInErrors++; /* Is this right - or do we ignore ? */
kfree_skb(skb,FREE_READ);
return(0);
}
/*
* Parse the ICMP message
*/
#ifdef CONFIG_IP_TRANSPARENT_PROXY
/*
* We may get non-local addresses and still want to handle them
* locally, due to transparent proxying.
* Thus, narrow down the test to what is really meant.
*/
if (daddr!=dev->pa_addr && ((r = ip_chk_addr(daddr)) == IS_BROADCAST || r == IS_MULTICAST))
#else
if (daddr && daddr!=dev->pa_addr && ip_chk_addr(daddr) != IS_MYADDR)
#endif
{
/*
* RFC 1122: 3.2.2.6 An ICMP_ECHO to broadcast MAY be silently ignored (we don't as it is used
* by some network mapping tools).
* RFC 1122: 3.2.2.8 An ICMP_TIMESTAMP MAY be silently discarded if to broadcast/multicast.
*/
if (icmph->type != ICMP_ECHO)
{
icmp_statistics.IcmpInErrors++;
kfree_skb(skb, FREE_READ);
return(0);
}
/*
* Reply the multicast/broadcast using a legal
* interface - in this case the device we got
* it from.
*/
daddr=dev->pa_addr;
}
len-=sizeof(struct icmphdr);
(*icmp_pointers[icmph->type].input)++;
(icmp_pointers[icmph->type].handler)(icmph,skb,skb->dev,saddr,daddr,len);
return 0;
}
int udp_user_read(int fd, void *buf, int len, struct udp_data *pri)
{
char buffer[BUF_SIZE], *udpStart = buffer + sizeof(struct iphdr);
CHECK_SOCKET(fd);
#ifdef INCLUDE_MAC
#error INCLUDE_MAC support does not work
#endif
const int invalidPacketLen = -1;
struct sockaddr_in srcAddr;
int srcAddrLen = sizeof(struct sockaddr_in);
int rcv_packet_len = invalidPacketLen;
__u32 srcIP;
if ((rcv_packet_len = recvfrom(fd, udpStart, BUF_SIZE, 0,
(struct sockaddr *) & srcAddr, &srcAddrLen)) <= 0) {
//DEBUG(1, "recvfrom");
return 0;
}
srcIP = srcAddr.sin_addr.s_addr;
if(rcv_packet_len > 0) {
DEBUG(2,"Packet recv'd(%d); need to perform unwrap operation\n",
rcv_packet_len);
/* XXX Copy unwrap code from kernel-level skbuff reorg stuff
* */
struct ipudp *iuh = (struct ipudp *)udpStart;
char *dataStart = (char*)(iuh + 1);
struct iphdr *iph = ((struct iphdr*)dataStart) - 1;
struct tcphdr *th = (struct tcphdr *)dataStart;
int cookedLen = rcv_packet_len - sizeof(struct ipudp) +
sizeof(struct iphdr);
if(cookedLen < sizeof(struct tcphdr)) {
printk("Cooked length is shorter than minimum tcp "
"header len\n");
return 0;
}
__u16 origCheck = th->check;
// This code does NOT respect the ipudp src and dest addresses
// Remove UDP header; push on IP header
if(iuh->saddr != srcIP) {
#ifndef SUPPORT_NAT
addrPrintComp("IPUDP header src did not match addr",
"!=",iuh->saddr, srcIP);
return 0;
#else
// th->check adjustment needed
th->check =
ip_nat_cheat_check(~iuh->saddr, srcIP,
th->check);
#endif
}
if(iuh->daddr != pri->local_addr) {
#ifndef SUPPORT_NAT
addrPrintComp("IPUDP header dest did not match addr",
"!=",iuh->daddr, pri->local_addr);
return 0;
#else
// th->check adjustment needed
th->check =
ip_nat_cheat_check(~iuh->daddr, pri->local_addr,
th->check);
#endif
}
int ihl = sizeof(*iph);
iph->version = 4;
iph->ihl = ihl / 4;
iph->tos = 0;
iph->tot_len = htons(cookedLen);
static int ip_id = 0;
iph->id = ip_id++;
iph->frag_off = 0;
iph->ttl = 255;
iph->protocol = IPPROTO_TCP;
iph->check = 0;
#ifdef SUPPORT_NAT
iph->saddr = srcIP;
iph->daddr = pri->local_addr;
#else
iph->saddr = iuh->saddr;
iph->daddr = iuh->daddr;
#endif
iph->check = ip_compute_csum((unsigned char *)iph, ihl);
// XXX should copy protocol from an ipudp field
DEBUG(2,"Returning cooked length %d, "
"origCheck = %d, newCheck = %d\n",
cookedLen, origCheck, th->check);
DEBUG_GUARD(2, printk("IPH: "); hexdump((char*)iph, ihl) );
memcpy(buf, (char*)iph, cookedLen);
return(cookedLen);
}
/* Compute an IPv4 header checksum, where 'data' points to the IPv4 header,
* and 'len' is the IPv4 header length. Return value is in network byte
* order.
*/
uint16_t nm_csum_ipv4(struct nm_iphdr *iph)
{
return ip_compute_csum((void*)iph, sizeof(struct nm_iphdr));
}
/*
* Handle ICMP messages in the outside-to-inside direction (incoming)
* and sometimes in outgoing direction from ip_vs_forward_icmp.
* Find any that might be relevant, check against existing connections,
* forward to the right destination host if relevant.
* Currently handles error types - unreachable, quench, ttl exceeded.
*/
static int ip_vs_in_icmp(struct sk_buff **skb_p)
{
struct sk_buff *skb = *skb_p;
struct iphdr *iph;
struct icmphdr *icmph;
struct iphdr *ciph; /* The ip header contained within the ICMP */
__u16 *pptr; /* port numbers from TCP/UDP contained header */
unsigned short len;
unsigned short clen, csize;
struct ip_vs_conn *cp;
struct rtable *rt; /* Route to the other host */
int mtu;
if (skb_is_nonlinear(skb)) {
if (skb_linearize(skb, GFP_ATOMIC) != 0)
return NF_DROP;
}
iph = skb->nh.iph;
ip_send_check(iph);
icmph = (struct icmphdr *)((char *)iph + (iph->ihl << 2));
len = ntohs(iph->tot_len) - (iph->ihl<<2);
if (len < sizeof(struct icmphdr))
return NF_DROP;
IP_VS_DBG(12, "icmp in (%d,%d) %u.%u.%u.%u -> %u.%u.%u.%u\n",
icmph->type, ntohs(icmp_id(icmph)),
NIPQUAD(iph->saddr), NIPQUAD(iph->daddr));
if ((icmph->type != ICMP_DEST_UNREACH) &&
(icmph->type != ICMP_SOURCE_QUENCH) &&
(icmph->type != ICMP_TIME_EXCEEDED))
return NF_ACCEPT;
/*
* If we get here we have an ICMP error of one of the above 3 types
* Now find the contained IP header
*/
clen = len - sizeof(struct icmphdr);
if (clen < sizeof(struct iphdr))
return NF_DROP;
ciph = (struct iphdr *) (icmph + 1);
csize = ciph->ihl << 2;
if (clen < csize)
return NF_DROP;
/* We are only interested ICMPs generated from TCP or UDP packets */
if (ciph->protocol != IPPROTO_UDP && ciph->protocol != IPPROTO_TCP)
return NF_ACCEPT;
/* Skip non-first embedded TCP/UDP fragments */
if (ciph->frag_off & __constant_htons(IP_OFFSET))
return NF_ACCEPT;
/* We need at least TCP/UDP ports here */
if (clen < csize + sizeof(struct udphdr))
return NF_DROP;
/* Ensure the checksum is correct */
if (ip_compute_csum((unsigned char *) icmph, len)) {
/* Failed checksum! */
IP_VS_ERR_RL("incoming ICMP: failed checksum from "
"%d.%d.%d.%d!\n", NIPQUAD(iph->saddr));
return NF_DROP;
}
pptr = (__u16 *)&(((char *)ciph)[csize]);
IP_VS_DBG(11, "Handling incoming ICMP for "
"%u.%u.%u.%u:%d -> %u.%u.%u.%u:%d\n",
NIPQUAD(ciph->saddr), ntohs(pptr[0]),
NIPQUAD(ciph->daddr), ntohs(pptr[1]));
/* This is pretty much what ip_vs_conn_in_get() does,
except parameters are in the reverse order */
cp = ip_vs_conn_in_get(ciph->protocol,
ciph->daddr, pptr[1],
ciph->saddr, pptr[0]);
if (cp == NULL)
return NF_ACCEPT;
ip_vs_in_stats(cp, skb);
/* The ICMP packet for VS/TUN, VS/DR and LOCALNODE will be
forwarded directly here, because there is no need to
translate address/port back */
if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ) {
int ret;
if (cp->packet_xmit)
ret = cp->packet_xmit(skb, cp);
else
ret = NF_ACCEPT;
atomic_inc(&cp->in_pkts);
ip_vs_conn_put(cp);
return ret;
}
/*
* mangle and send the packet here
*/
if (!(rt = __ip_vs_get_out_rt(cp, RT_TOS(iph->tos))))
goto tx_error_icmp;
/* MTU checking */
mtu = rt->u.dst.pmtu;
if ((skb->len > mtu) && (iph->frag_off&__constant_htons(IP_DF))) {
ip_rt_put(rt);
icmp_send(skb, ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED, htonl(mtu));
IP_VS_DBG_RL("ip_vs_in_icmp(): frag needed\n");
goto tx_error;
}
/* drop old route */
dst_release(skb->dst);
skb->dst = &rt->u.dst;
/* copy-on-write the packet before mangling it */
if (ip_vs_skb_cow(skb, rt->u.dst.dev->hard_header_len,
&iph, (unsigned char**)&icmph)) {
ip_vs_conn_put(cp);
return NF_DROP;
}
ciph = (struct iphdr *) (icmph + 1);
pptr = (__u16 *)&(((char *)ciph)[csize]);
/* The ICMP packet for VS/NAT must be written to correct addresses
before being forwarded to the right server */
/* First change the dest IP address, and recalc checksum */
iph->daddr = cp->daddr;
ip_send_check(iph);
/* Now change the *source* address in the contained IP */
ciph->saddr = cp->daddr;
ip_send_check(ciph);
/* the TCP/UDP source port - cannot redo check */
pptr[0] = cp->dport;
/* And finally the ICMP checksum */
icmph->checksum = 0;
icmph->checksum = ip_compute_csum((unsigned char *) icmph, len);
skb->ip_summed = CHECKSUM_UNNECESSARY;
IP_VS_DBG(11, "Forwarding incoming ICMP to "
"%u.%u.%u.%u:%d -> %u.%u.%u.%u:%d\n",
NIPQUAD(ciph->saddr), ntohs(pptr[0]),
NIPQUAD(ciph->daddr), ntohs(pptr[1]));
#ifdef CONFIG_NETFILTER_DEBUG
skb->nf_debug = 1 << NF_IP_LOCAL_OUT;
#endif /* CONFIG_NETFILTER_DEBUG */
ip_send(skb);
ip_vs_conn_put(cp);
return NF_STOLEN;
tx_error_icmp:
dst_link_failure(skb);
tx_error:
dev_kfree_skb(skb);
ip_vs_conn_put(cp);
return NF_STOLEN;
}
/*
* Handle ICMP messages in the inside-to-outside direction (outgoing).
* Find any that might be relevant, check against existing connections,
* forward to the right destination host if relevant.
* Currently handles error types - unreachable, quench, ttl exceeded.
* (Only used in VS/NAT)
*/
static int ip_vs_out_icmp(struct sk_buff **skb_p)
{
struct sk_buff *skb = *skb_p;
struct iphdr *iph;
struct icmphdr *icmph;
struct iphdr *ciph; /* The ip header contained within the ICMP */
__u16 *pptr; /* port numbers from TCP/UDP contained header */
unsigned short ihl;
unsigned short len;
unsigned short clen, csize;
struct ip_vs_conn *cp;
/* reassemble IP fragments, but will it happen in ICMP packets?? */
if (skb->nh.iph->frag_off & __constant_htons(IP_MF|IP_OFFSET)) {
skb = ip_defrag(skb, IP_DEFRAG_VS_OUT);
if (!skb)
return NF_STOLEN;
*skb_p = skb;
}
if (skb_is_nonlinear(skb)) {
if (skb_linearize(skb, GFP_ATOMIC) != 0)
return NF_DROP;
ip_send_check(skb->nh.iph);
}
iph = skb->nh.iph;
ihl = iph->ihl << 2;
icmph = (struct icmphdr *)((char *)iph + ihl);
len = ntohs(iph->tot_len) - ihl;
if (len < sizeof(struct icmphdr))
return NF_DROP;
IP_VS_DBG(12, "outgoing ICMP (%d,%d) %u.%u.%u.%u->%u.%u.%u.%u\n",
icmph->type, ntohs(icmp_id(icmph)),
NIPQUAD(iph->saddr), NIPQUAD(iph->daddr));
/*
* Work through seeing if this is for us.
* These checks are supposed to be in an order that means easy
* things are checked first to speed up processing.... however
* this means that some packets will manage to get a long way
* down this stack and then be rejected, but that's life.
*/
if ((icmph->type != ICMP_DEST_UNREACH) &&
(icmph->type != ICMP_SOURCE_QUENCH) &&
(icmph->type != ICMP_TIME_EXCEEDED))
return NF_ACCEPT;
/* Now find the contained IP header */
clen = len - sizeof(struct icmphdr);
if (clen < sizeof(struct iphdr))
return NF_DROP;
ciph = (struct iphdr *) (icmph + 1);
csize = ciph->ihl << 2;
if (clen < csize)
return NF_DROP;
/* We are only interested ICMPs generated from TCP or UDP packets */
if (ciph->protocol != IPPROTO_UDP && ciph->protocol != IPPROTO_TCP)
return NF_ACCEPT;
/* Skip non-first embedded TCP/UDP fragments */
if (ciph->frag_off & __constant_htons(IP_OFFSET))
return NF_ACCEPT;
/* We need at least TCP/UDP ports here */
if (clen < csize + sizeof(struct udphdr))
return NF_DROP;
/*
* Find the ports involved - this packet was
* incoming so the ports are right way round
* (but reversed relative to outer IP header!)
*/
pptr = (__u16 *)&(((char *)ciph)[csize]);
/* Ensure the checksum is correct */
if (ip_compute_csum((unsigned char *) icmph, len)) {
/* Failed checksum! */
IP_VS_DBG(1, "forward ICMP: failed checksum from %d.%d.%d.%d!\n",
NIPQUAD(iph->saddr));
return NF_DROP;
}
IP_VS_DBG(11, "Handling outgoing ICMP for "
"%u.%u.%u.%u:%d -> %u.%u.%u.%u:%d\n",
NIPQUAD(ciph->saddr), ntohs(pptr[0]),
NIPQUAD(ciph->daddr), ntohs(pptr[1]));
/* ciph content is actually <protocol, caddr, cport, daddr, dport> */
cp = ip_vs_conn_out_get(ciph->protocol, ciph->daddr, pptr[1],
ciph->saddr, pptr[0]);
if (!cp)
return NF_ACCEPT;
if (IP_VS_FWD_METHOD(cp) != 0) {
IP_VS_ERR("shouldn't reach here, because the box is on the"
"half connection in the tun/dr module.\n");
}
/* Now we do real damage to this packet...! */
/* First change the source IP address, and recalc checksum */
iph->saddr = cp->vaddr;
ip_send_check(iph);
/* Now change the *dest* address in the contained IP */
ciph->daddr = cp->vaddr;
ip_send_check(ciph);
/* the TCP/UDP dest port - cannot redo check */
pptr[1] = cp->vport;
/* And finally the ICMP checksum */
icmph->checksum = 0;
icmph->checksum = ip_compute_csum((unsigned char *) icmph, len);
skb->ip_summed = CHECKSUM_UNNECESSARY;
/* do the statistics and put it back */
ip_vs_out_stats(cp, skb);
ip_vs_conn_put(cp);
IP_VS_DBG(11, "Forwarding correct outgoing ICMP to "
"%u.%u.%u.%u:%d -> %u.%u.%u.%u:%d\n",
NIPQUAD(ciph->saddr), ntohs(pptr[0]),
NIPQUAD(ciph->daddr), ntohs(pptr[1]));
skb->nfcache |= NFC_IPVS_PROPERTY;
return NF_ACCEPT;
}
struct iphdr *diph = template->iph;
int ihl = template->ihl;
BUG_TRAP(ihl == 20);
int tot_len = ntohs(diph->tot_len) + adjPacketLen;
#if 0
printk("new tot_len = %d\n", tot_len);
#endif
diph->saddr = newSrc;
diph->daddr = newDest;
diph->tot_len = htons(tot_len);
diph->protocol = newProto;
diph->check = 0;
// Compute checksum
diph->check = ip_compute_csum((unsigned char *)diph, ihl);
skb->nh.iph = (struct iphdr*)skb_push(skb, ihl);
memcpy((char*)skb->nh.iph, diph, ihl);
if(updateFlags & INCLUDE_LL) {
// push on link layer header
BUG_TRAP(template->ll_len == 14);
skb->mac.raw = skb_push(skb, template->ll_len);
memcpy(skb->mac.raw, template->ll_rawh, template->ll_len);
}
#if 0
printk("dumping final iph: \n");
hexdump(skb->nh.iph, ihl);
#endif
}
int ip_fw_masq_icmp(struct sk_buff **skb_p, struct device *dev)
{
struct sk_buff *skb = *skb_p;
struct iphdr *iph = skb->h.iph;
struct icmphdr *icmph = (struct icmphdr *)((char *)iph + (iph->ihl<<2));
struct iphdr *ciph; /* The ip header contained within the ICMP */
__u16 *pptr; /* port numbers from TCP/UDP contained header */
struct ip_masq *ms;
unsigned short len = ntohs(iph->tot_len) - (iph->ihl * 4);
#ifdef DEBUG_CONFIG_IP_MASQUERADE_ICMP
printk("Incoming forward ICMP (%d,%d) %lX -> %lX\n",
icmph->type, ntohs(icmp_id(icmph)),
ntohl(iph->saddr), ntohl(iph->daddr));
#endif
#ifdef CONFIG_IP_MASQUERADE_ICMP
if ((icmph->type == ICMP_ECHO ) ||
(icmph->type == ICMP_TIMESTAMP ) ||
(icmph->type == ICMP_INFO_REQUEST ) ||
(icmph->type == ICMP_ADDRESS )) {
#ifdef DEBUG_CONFIG_IP_MASQUERADE_ICMP
printk("MASQ: icmp request rcv %lX->%lX id %d type %d\n",
ntohl(iph->saddr),
ntohl(iph->daddr),
ntohs(icmp_id(icmph)),
icmph->type);
#endif
ms = ip_masq_out_get_2(iph->protocol,
iph->saddr,
icmp_id(icmph),
iph->daddr,
icmp_hv_req(icmph));
if (ms == NULL) {
ms = ip_masq_new(dev,
iph->protocol,
iph->saddr,
icmp_id(icmph),
iph->daddr,
icmp_hv_req(icmph),
0);
if (ms == NULL)
return (-1);
#ifdef DEBUG_CONFIG_IP_MASQUERADE_ICMP
printk("MASQ: Create new icmp entry\n");
#endif
}
ip_masq_set_expire(ms, 0);
/* Rewrite source address */
/*
* If sysctl !=0 and no pkt has been received yet
* in this tunnel and routing iface address has changed...
* "You are welcome, diald".
*/
if ( sysctl_ip_dynaddr && ms->flags & IP_MASQ_F_NO_REPLY && dev->pa_addr != ms->maddr) {
unsigned long flags;
#ifdef DEBUG_CONFIG_IP_MASQUERADE
printk(KERN_INFO "ip_fw_masq_icmp(): change masq.addr %s",
in_ntoa(ms->maddr));
printk("-> %s\n", in_ntoa(dev->pa_addr));
#endif
save_flags(flags);
cli();
ip_masq_unhash(ms);
ms->maddr = dev->pa_addr;
ip_masq_hash(ms);
restore_flags(flags);
}
iph->saddr = ms->maddr;
ip_send_check(iph);
/* Rewrite port (id) */
(icmph->un).echo.id = ms->mport;
icmph->checksum = 0;
icmph->checksum = ip_compute_csum((unsigned char *)icmph, len);
ip_masq_set_expire(ms, MASQUERADE_EXPIRE_ICMP);
#ifdef DEBUG_CONFIG_IP_MASQUERADE_ICMP
printk("MASQ: icmp request rwt %lX->%lX id %d type %d\n",
ntohl(iph->saddr),
ntohl(iph->daddr),
ntohs(icmp_id(icmph)),
icmph->type);
#endif
return (1);
}
#endif
/*
* Work through seeing if this is for us.
* These checks are supposed to be in an order that
* means easy things are checked first to speed up
* processing.... however this means that some
* packets will manage to get a long way down this
* stack and then be rejected, but thats life
*/
if ((icmph->type != ICMP_DEST_UNREACH) &&
(icmph->type != ICMP_SOURCE_QUENCH) &&
(icmph->type != ICMP_TIME_EXCEEDED))
return 0;
/* Now find the contained IP header */
ciph = (struct iphdr *) (icmph + 1);
#ifdef CONFIG_IP_MASQUERADE_ICMP
if (ciph->protocol == IPPROTO_ICMP) {
/*
* This section handles ICMP errors for ICMP packets
*/
struct icmphdr *cicmph = (struct icmphdr *)((char *)ciph +
(ciph->ihl<<2));
#ifdef DEBUG_CONFIG_IP_MASQUERADE_ICMP
printk("MASQ: fw icmp/icmp rcv %lX->%lX id %d type %d\n",
ntohl(ciph->saddr),
ntohl(ciph->daddr),
ntohs(icmp_id(cicmph)),
cicmph->type);
#endif
ms = ip_masq_out_get_2(ciph->protocol,
ciph->daddr,
icmp_id(cicmph),
ciph->saddr,
icmp_hv_rep(cicmph));
if (ms == NULL)
return 0;
/* Now we do real damage to this packet...! */
/* First change the source IP address, and recalc checksum */
iph->saddr = ms->maddr;
ip_send_check(iph);
/* Now change the *dest* address in the contained IP */
ciph->daddr = ms->maddr;
ip_send_check(ciph);
/* Change the ID to the masqed one! */
(cicmph->un).echo.id = ms->mport;
/* And finally the ICMP checksum */
icmph->checksum = 0;
icmph->checksum = ip_compute_csum((unsigned char *) icmph, len);
#ifdef DEBUG_CONFIG_IP_MASQUERADE_ICMP
printk("MASQ: fw icmp/icmp rwt %lX->%lX id %d type %d\n",
ntohl(ciph->saddr),
ntohl(ciph->daddr),
ntohs(icmp_id(cicmph)),
cicmph->type);
#endif
return 1;
}
#endif /* CONFIG_IP_MASQUERADE_ICMP */
/* We are only interested ICMPs generated from TCP or UDP packets */
if ((ciph->protocol != IPPROTO_UDP) && (ciph->protocol != IPPROTO_TCP))
return 0;
/*
* Find the ports involved - this packet was
* incoming so the ports are right way round
* (but reversed relative to outer IP header!)
*/
pptr = (__u16 *)&(((char *)ciph)[ciph->ihl*4]);
/* Ensure the checksum is correct */
if (ip_compute_csum((unsigned char *) icmph, len))
{
/* Failed checksum! */
printk(KERN_DEBUG "MASQ: forward ICMP: failed checksum from %s!\n",
in_ntoa(iph->saddr));
return(-1);
}
#ifdef DEBUG_CONFIG_IP_MASQUERADE
printk("Handling forward ICMP for %lX:%X -> %lX:%X\n",
ntohl(ciph->saddr), ntohs(pptr[0]),
ntohl(ciph->daddr), ntohs(pptr[1]));
#endif
/* This is pretty much what ip_masq_out_get() does */
ms = ip_masq_out_get_2(ciph->protocol,
ciph->daddr,
pptr[1],
ciph->saddr,
pptr[0]);
if (ms == NULL)
return 0;
/* Now we do real damage to this packet...! */
/* First change the source IP address, and recalc checksum */
iph->saddr = ms->maddr;
ip_send_check(iph);
/* Now change the *dest* address in the contained IP */
ciph->daddr = ms->maddr;
ip_send_check(ciph);
/* the TCP/UDP dest port - cannot redo check */
pptr[1] = ms->mport;
/* And finally the ICMP checksum */
icmph->checksum = 0;
icmph->checksum = ip_compute_csum((unsigned char *) icmph, len);
#ifdef DEBUG_CONFIG_IP_MASQUERADE
printk("Rewrote forward ICMP to %lX:%X -> %lX:%X\n",
ntohl(ciph->saddr), ntohs(pptr[0]),
ntohl(ciph->daddr), ntohs(pptr[1]));
#endif
return 1;
}
int ip_fw_demasq_icmp(struct sk_buff **skb_p, struct device *dev)
{
struct sk_buff *skb = *skb_p;
struct iphdr *iph = skb->h.iph;
struct icmphdr *icmph = (struct icmphdr *)((char *)iph + (iph->ihl<<2));
struct iphdr *ciph; /* The ip header contained within the ICMP */
__u16 *pptr; /* port numbers from TCP/UDP contained header */
struct ip_masq *ms;
unsigned short len = ntohs(iph->tot_len) - (iph->ihl * 4);
#ifdef DEBUG_CONFIG_IP_MASQUERADE_ICMP
printk("MASQ: icmp in/rev (%d,%d) %lX -> %lX\n",
icmph->type, ntohs(icmp_id(icmph)),
ntohl(iph->saddr), ntohl(iph->daddr));
#endif
#ifdef CONFIG_IP_MASQUERADE_ICMP
if ((icmph->type == ICMP_ECHOREPLY) ||
(icmph->type == ICMP_TIMESTAMPREPLY) ||
(icmph->type == ICMP_INFO_REPLY) ||
(icmph->type == ICMP_ADDRESSREPLY)) {
#ifdef DEBUG_CONFIG_IP_MASQUERADE_ICMP
printk("MASQ: icmp reply rcv %lX->%lX id %d type %d, req %d\n",
ntohl(iph->saddr),
ntohl(iph->daddr),
ntohs(icmp_id(icmph)),
icmph->type,
icmp_type_request(icmph->type));
#endif
ms = ip_masq_in_get_2(iph->protocol,
iph->saddr,
icmp_hv_rep(icmph),
iph->daddr,
icmp_id(icmph));
if (ms == NULL)
return 0;
ip_masq_set_expire(ms,0);
/*
* got reply, so clear flag
*/
ms->flags &= ~IP_MASQ_F_NO_REPLY;
/* Reset source address */
iph->daddr = ms->saddr;
/* Redo IP header checksum */
ip_send_check(iph);
/* Set ID to fake port number */
(icmph->un).echo.id = ms->sport;
/* Reset ICMP checksum and set expiry */
icmph->checksum=0;
icmph->checksum=ip_compute_csum((unsigned char *)icmph,len);
ip_masq_set_expire(ms, MASQUERADE_EXPIRE_ICMP);
#ifdef DEBUG_CONFIG_IP_MASQUERADE_ICMP
printk("MASQ: icmp reply rwt %lX->%lX id %d type %d\n",
ntohl(iph->saddr),
ntohl(iph->daddr),
ntohs(icmp_id(icmph)),
icmph->type);
#endif
return 1;
} else {
#endif
if ((icmph->type != ICMP_DEST_UNREACH) &&
(icmph->type != ICMP_SOURCE_QUENCH) &&
(icmph->type != ICMP_TIME_EXCEEDED))
return 0;
#ifdef CONFIG_IP_MASQUERADE_ICMP
}
#endif
/*
* If we get here we have an ICMP error of one of the above 3 types
* Now find the contained IP header
*/
ciph = (struct iphdr *) (icmph + 1);
#ifdef CONFIG_IP_MASQUERADE_ICMP
if (ciph->protocol == IPPROTO_ICMP) {
/*
* This section handles ICMP errors for ICMP packets
*
* First get a new ICMP header structure out of the IP packet
*/
struct icmphdr *cicmph = (struct icmphdr *)((char *)ciph +
(ciph->ihl<<2));
#ifdef DEBUG_CONFIG_IP_MASQUERADE_ICMP
printk("MASQ: rv icmp/icmp rcv %lX->%lX id %d type %d\n",
ntohl(ciph->saddr),
ntohl(ciph->daddr),
ntohs(icmp_id(cicmph)),
cicmph->type);
#endif
ms = ip_masq_in_get_2(ciph->protocol,
ciph->daddr,
icmp_hv_req(cicmph),
ciph->saddr,
icmp_id(cicmph));
if (ms == NULL)
return 0;
/* Now we do real damage to this packet...! */
/* First change the dest IP address, and recalc checksum */
iph->daddr = ms->saddr;
ip_send_check(iph);
/* Now change the *source* address in the contained IP */
ciph->saddr = ms->saddr;
ip_send_check(ciph);
/* Change the ID to the original one! */
(cicmph->un).echo.id = ms->sport;
/* And finally the ICMP checksum */
icmph->checksum = 0;
icmph->checksum = ip_compute_csum((unsigned char *) icmph, len);
#ifdef DEBUG_CONFIG_IP_MASQUERADE_ICMP
printk("MASQ: rv icmp/icmp rwt %lX->%lX id %d type %d\n",
ntohl(ciph->saddr),
ntohl(ciph->daddr),
ntohs(icmp_id(cicmph)),
cicmph->type);
#endif
return 1;
}
#endif /* CONFIG_IP_MASQUERADE_ICMP */
/* We are only interested ICMPs generated from TCP or UDP packets */
if ((ciph->protocol != IPPROTO_UDP) &&
(ciph->protocol != IPPROTO_TCP))
return 0;
/*
* Find the ports involved - remember this packet was
* *outgoing* so the ports are reversed (and addresses)
*/
pptr = (__u16 *)&(((char *)ciph)[ciph->ihl*4]);
if (ntohs(pptr[0]) < PORT_MASQ_BEGIN ||
ntohs(pptr[0]) > PORT_MASQ_END)
return 0;
/* Ensure the checksum is correct */
if (ip_compute_csum((unsigned char *) icmph, len))
{
/* Failed checksum! */
printk(KERN_DEBUG "MASQ: reverse ICMP: failed checksum from %s!\n",
in_ntoa(iph->saddr));
return(-1);
}
#ifdef DEBUG_CONFIG_IP_MASQUERADE
printk("Handling reverse ICMP for %lX:%X -> %lX:%X\n",
ntohl(ciph->saddr), ntohs(pptr[0]),
ntohl(ciph->daddr), ntohs(pptr[1]));
#endif
/* This is pretty much what ip_masq_in_get() does, except params are wrong way round */
ms = ip_masq_in_get_2(ciph->protocol,
ciph->daddr,
pptr[1],
ciph->saddr,
pptr[0]);
if (ms == NULL)
return 0;
/* Now we do real damage to this packet...! */
/* First change the dest IP address, and recalc checksum */
iph->daddr = ms->saddr;
ip_send_check(iph);
/* Now change the *source* address in the contained IP */
ciph->saddr = ms->saddr;
ip_send_check(ciph);
/* the TCP/UDP source port - cannot redo check */
pptr[0] = ms->sport;
/* And finally the ICMP checksum */
icmph->checksum = 0;
icmph->checksum = ip_compute_csum((unsigned char *) icmph, len);
#ifdef DEBUG_CONFIG_IP_MASQUERADE
printk("Rewrote reverse ICMP to %lX:%X -> %lX:%X\n",
ntohl(ciph->saddr), ntohs(pptr[0]),
ntohl(ciph->daddr), ntohs(pptr[1]));
#endif
return 1;
}
int igmp_rcv(struct sk_buff *skb)
{
/* This basically follows the spec line by line -- see RFC1112 */
struct igmphdr *ih = skb->h.igmph;
struct in_device *in_dev = in_dev_get(skb->dev);
int len = skb->len;
if (in_dev==NULL) {
kfree_skb(skb);
return 0;
}
if (skb_is_nonlinear(skb)) {
if (skb_linearize(skb, GFP_ATOMIC) != 0) {
kfree_skb(skb);
return -ENOMEM;
}
ih = skb->h.igmph;
}
if (len < sizeof(struct igmphdr) || ip_compute_csum((void *)ih, len)) {
in_dev_put(in_dev);
kfree_skb(skb);
return 0;
}
#ifdef CONFIG_RG_IGMP_PROXY
igmprx_recv(skb);
#endif
#ifdef CONFIG_RG_IGMP_PROXY_MODULE
if (igmp_proxy_recv)
igmp_proxy_recv(skb);
#endif
switch (ih->type) {
case IGMP_HOST_MEMBERSHIP_QUERY:
igmp_heard_query(in_dev, ih->code, ih->group);
break;
case IGMP_HOST_MEMBERSHIP_REPORT:
case IGMP_HOST_NEW_MEMBERSHIP_REPORT:
/* Is it our report looped back? */
if (((struct rtable*)skb->dst)->key.iif == 0)
break;
igmp_heard_report(in_dev, ih->group);
break;
case IGMP_PIM:
#ifdef CONFIG_IP_PIMSM_V1
in_dev_put(in_dev);
return pim_rcv_v1(skb);
#endif
case IGMP_DVMRP:
case IGMP_TRACE:
case IGMP_HOST_LEAVE_MESSAGE:
case IGMP_MTRACE:
case IGMP_MTRACE_RESP:
break;
default:
// NETDEBUG(printk(KERN_DEBUG "New IGMP type=%d, why we do not know about it?\n", ih->type));
;
}
in_dev_put(in_dev);
kfree_skb(skb);
return 0;
}
static void send_unreach(struct sk_buff *skb_in, int code)
{
struct iphdr *iph;
struct udphdr *udph;
struct icmphdr *icmph;
struct sk_buff *nskb;
u32 saddr;
u8 tos;
int hh_len, length;
struct rtable *rt = (struct rtable*)skb_in->dst;
unsigned char *data;
if (!rt)
return;
/* FIXME: Use sysctl number. --RR */
if (!xrlim_allow(&rt->u.dst, 1*HZ))
return;
iph = skb_in->nh.iph;
/* No replies to physical multicast/broadcast */
if (skb_in->pkt_type!=PACKET_HOST)
return;
/* Now check at the protocol level */
if (rt->rt_flags&(RTCF_BROADCAST|RTCF_MULTICAST))
return;
/* Only reply to fragment 0. */
if (iph->frag_off&htons(IP_OFFSET))
return;
/* if UDP checksum is set, verify it's correct */
if (iph->protocol == IPPROTO_UDP
&& skb_in->tail-(u8*)iph >= sizeof(struct udphdr)) {
int datalen = skb_in->len - (iph->ihl<<2);
udph = (struct udphdr *)((char *)iph + (iph->ihl<<2));
if (udph->check
&& csum_tcpudp_magic(iph->saddr, iph->daddr,
datalen, IPPROTO_UDP,
csum_partial((char *)udph, datalen,
0)) != 0)
return;
}
/* If we send an ICMP error to an ICMP error a mess would result.. */
if (iph->protocol == IPPROTO_ICMP
&& skb_in->tail-(u8*)iph >= sizeof(struct icmphdr)) {
icmph = (struct icmphdr *)((char *)iph + (iph->ihl<<2));
/* Between echo-reply (0) and timestamp (13),
everything except echo-request (8) is an error.
Also, anything greater than NR_ICMP_TYPES is
unknown, and hence should be treated as an error... */
if ((icmph->type < ICMP_TIMESTAMP
&& icmph->type != ICMP_ECHOREPLY
&& icmph->type != ICMP_ECHO)
|| icmph->type > NR_ICMP_TYPES)
return;
}
saddr = iph->daddr;
if (!(rt->rt_flags & RTCF_LOCAL))
saddr = 0;
tos = (iph->tos & IPTOS_TOS_MASK) | IPTOS_PREC_INTERNETCONTROL;
if (ip_route_output(&rt, iph->saddr, saddr, RT_TOS(tos), 0))
return;
/* RFC says return as much as we can without exceeding 576 bytes. */
length = skb_in->len + sizeof(struct iphdr) + sizeof(struct icmphdr);
if (length > rt->u.dst.pmtu)
length = rt->u.dst.pmtu;
if (length > 576)
length = 576;
hh_len = (rt->u.dst.dev->hard_header_len + 15)&~15;
nskb = alloc_skb(hh_len+15+length, GFP_ATOMIC);
if (!nskb) {
ip_rt_put(rt);
return;
}
nskb->priority = 0;
nskb->dst = &rt->u.dst;
skb_reserve(nskb, hh_len);
/* Set up IP header */
iph = nskb->nh.iph
= (struct iphdr *)skb_put(nskb, sizeof(struct iphdr));
iph->version=4;
iph->ihl=5;
iph->tos=tos;
iph->tot_len = htons(length);
/* PMTU discovery never applies to ICMP packets. */
iph->frag_off = 0;
iph->ttl = MAXTTL;
ip_select_ident(iph, &rt->u.dst, NULL);
iph->protocol=IPPROTO_ICMP;
iph->saddr=rt->rt_src;
iph->daddr=rt->rt_dst;
iph->check=0;
iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
/* Set up ICMP header. */
icmph = nskb->h.icmph
= (struct icmphdr *)skb_put(nskb, sizeof(struct icmphdr));
icmph->type = ICMP_DEST_UNREACH;
icmph->code = code;
icmph->un.gateway = 0;
icmph->checksum = 0;
/* Copy as much of original packet as will fit */
data = skb_put(nskb,
length - sizeof(struct iphdr) - sizeof(struct icmphdr));
/* FIXME: won't work with nonlinear skbs --RR */
memcpy(data, skb_in->nh.iph,
length - sizeof(struct iphdr) - sizeof(struct icmphdr));
icmph->checksum = ip_compute_csum((unsigned char *)icmph,
length - sizeof(struct iphdr));
nf_ct_attach(nskb, skb_in);
NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, nskb, NULL, nskb->dst->dev,
ip_finish_output);
}
int
icmp_rcv(struct sk_buff *skb1, struct device *dev, struct options *opt,
unsigned long daddr, unsigned short len,
unsigned long saddr, int redo, struct ip_protocol *protocol )
{
int size, offset;
struct icmp_header *icmph, *icmphr;
struct sk_buff *skb;
unsigned char *buff;
/* drop broadcast packets. */
if ((daddr & 0xff000000) == 0 || (daddr & 0xff000000) == 0xff000000)
{
skb1->sk = NULL;
free_skb (skb1, FREE_READ);
return (0);
}
buff = skb1->h.raw;
icmph = (struct icmp_header *)buff;
/* Validate the packet first */
if( icmph->checksum )
{ /* Checksums Enabled? */
if( ip_compute_csum( (unsigned char *)icmph, len ) )
{
/* Failed checksum! */
PRINTK("\nICMP ECHO failed checksum!");
skb1->sk = NULL;
free_skb (skb1, FREE_READ);
return (0);
}
}
print_icmph(icmph);
/* Parse the ICMP message */
switch( icmph->type )
{
case ICMP_DEST_UNREACH:
case ICMP_SOURCE_QUENCH:
{
struct ip_header *iph;
struct ip_protocol *ipprot;
unsigned char hash;
int err;
err = icmph->type << 8 | icmph->code;
/* we need to cause the socket to be closed and the error message
to be set appropriately. */
iph = (struct ip_header *)(icmph+1);
/* get the protocol(s) */
hash = iph->protocol & (MAX_IP_PROTOS -1 );
for (ipprot = ip_protos[hash]; ipprot != NULL; ipprot=ipprot->next)
{
/* pass it off to everyone who wants it. */
ipprot->err_handler (err, (unsigned char *)iph+4*iph->ihl,
iph->daddr, iph->saddr, ipprot);
}
skb1->sk = NULL;
free_skb (skb1, FREE_READ);
return (0);
}
case ICMP_REDIRECT:
{
/* we need to put a new route in the routing table. */
struct rtable *rt; /* we will add a new route. */
struct ip_header *iph;
iph = (struct ip_header *)(icmph+1);
rt = malloc (sizeof (*rt));
if (rt != NULL)
{
rt->net = iph->daddr;
/* assume class C network. Technically this is incorrect,
but will give it a try. */
if ((icmph->code & 1) == 0) rt->net &= 0x00ffffff;
rt->dev = dev;
rt->router = icmph->un.gateway;
add_route (rt);
}
skb1->sk = NULL;
free_skb (skb1, FREE_READ);
return (0);
}
case ICMP_ECHO:
/* Allocate an sk_buff response buffer (assume 64 byte IP header) */
size = sizeof( struct sk_buff ) + dev->hard_header_len + 64 + len;
skb = malloc( size );
if (skb == NULL)
{
skb1->sk = NULL;
free_skb (skb1, FREE_READ);
return (0);
}
skb->sk = NULL;
skb->mem_addr = skb;
skb->mem_len = size;
/* Build Layer 2-3 headers for message back to source */
offset = ip_build_header( skb, daddr, saddr, &dev, IP_ICMP, opt, len );
if (offset < 0)
{
/* Problems building header */
PRINTK("\nCould not build IP Header for ICMP ECHO Response");
free_s (skb->mem_addr, skb->mem_len);
skb1->sk = NULL;
free_skb (skb1, FREE_READ);
return( 0 ); /* just toss the received packet */
}
/* Readjust length according to actual IP header size */
skb->len = offset + len;
/* Build ICMP_ECHO Response message */
icmphr = (struct icmp_header *)( (char *)( skb + 1 ) + offset );
memcpy( (char *)icmphr, (char *)icmph, len );
icmphr->type = ICMP_ECHOREPLY;
icmphr->code = 0;
icmphr->checksum = 0;
if( icmph->checksum )
{ /* Calculate Checksum */
icmphr->checksum = ip_compute_csum( (void *)icmphr, len );
}
/* Ship it out - free it when done */
ip_queue_xmit( (volatile struct sock *)NULL, dev, skb, 1 );
skb1->sk = NULL;
free_skb (skb1, FREE_READ);
return( 0 );
default:
PRINTK("\nUnsupported ICMP type = x%x", icmph->type );
skb1->sk = NULL;
free_skb (skb1, FREE_READ);
return( 0 ); /* just toss the packet */
}
/* should be unecessary, but just in case. */
skb1->sk = NULL;
free_skb (skb1, FREE_READ);
return( 0 ); /* just toss the packet */
}
static int ipv4_icmp_post(void *l4_hdr, u16 datagram_len, struct tuple *tuple4)
{
struct icmphdr *hdr = l4_hdr;
hdr->checksum = ip_compute_csum(hdr, datagram_len);
return 0;
}
static unsigned char *kexec_bn2cl(void *pg)
{
struct Elf32_Bhdr *bhdrp;
Elf32_Nhdr *nhdrp;
unsigned char *desc;
unsigned char *command_line;
__sum16 csum;
bhdrp = (struct Elf32_Bhdr *) pg;
/*
* This routine is invoked for every source page, so make
* sure to quietly ignore every impossible page.
*/
if (bhdrp->b_signature != ELF_BOOT_MAGIC ||
bhdrp->b_size > PAGE_SIZE)
return 0;
/*
* If we get a checksum mismatch, warn with the checksum
* so we can diagnose better.
*/
csum = ip_compute_csum(pg, bhdrp->b_size);
if (csum != 0) {
pr_warning("%s: bad checksum %#x (size %d)\n",
__func__, csum, bhdrp->b_size);
return 0;
}
nhdrp = (Elf32_Nhdr *) (bhdrp + 1);
while (nhdrp->n_type != EBN_COMMAND_LINE) {
desc = (unsigned char *) (nhdrp + 1);
desc += roundupsz(nhdrp->n_descsz);
nhdrp = (Elf32_Nhdr *) desc;
/* still in bounds? */
if ((unsigned char *) (nhdrp + 1) >
((unsigned char *) pg) + bhdrp->b_size) {
pr_info("%s: out of bounds\n", __func__);
return 0;
}
}
command_line = (unsigned char *) (nhdrp + 1);
desc = command_line;
while (*desc != '\0') {
desc++;
if (((unsigned long)desc & PAGE_MASK) != (unsigned long)pg) {
pr_info("%s: ran off end of page\n",
__func__);
return 0;
}
}
return command_line;
}
static __u16 sd_dif_ip_fn(void *data, unsigned int len)
{
return ip_compute_csum(data, len);
}