diff options
Diffstat (limited to 'pfinet.old/linux-src/net/ipv4/ip_output.c~')
| -rw-r--r-- | pfinet.old/linux-src/net/ipv4/ip_output.c~ | 1000 |
1 files changed, 0 insertions, 1000 deletions
diff --git a/pfinet.old/linux-src/net/ipv4/ip_output.c~ b/pfinet.old/linux-src/net/ipv4/ip_output.c~ deleted file mode 100644 index 89272d6b..00000000 --- a/pfinet.old/linux-src/net/ipv4/ip_output.c~ +++ /dev/null @@ -1,1000 +0,0 @@ -/* - * INET An implementation of the TCP/IP protocol suite for the LINUX - * operating system. INET is implemented using the BSD Socket - * interface as the means of communication with the user level. - * - * The Internet Protocol (IP) output module. - * - * Version: $Id: ip_output.c,v 1.67.2.1 1999/09/07 02:25:23 davem Exp $ - * - * Authors: Ross Biro, <bir7@leland.Stanford.Edu> - * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> - * Donald Becker, <becker@super.org> - * Alan Cox, <Alan.Cox@linux.org> - * Richard Underwood - * Stefan Becker, <stefanb@yello.ping.de> - * Jorge Cwik, <jorge@laser.satlink.net> - * Arnt Gulbrandsen, <agulbra@nvg.unit.no> - * - * See ip_input.c for original log - * - * Fixes: - * Alan Cox : Missing nonblock feature in ip_build_xmit. - * Mike Kilburn : htons() missing in ip_build_xmit. - * Bradford Johnson: Fix faulty handling of some frames when - * no route is found. - * Alexander Demenshin: Missing sk/skb free in ip_queue_xmit - * (in case if packet not accepted by - * output firewall rules) - * Mike McLagan : Routing by source - * Alexey Kuznetsov: use new route cache - * Andi Kleen: Fix broken PMTU recovery and remove - * some redundant tests. - * Vitaly E. Lavrov : Transparent proxy revived after year coma. - * Andi Kleen : Replace ip_reply with ip_send_reply. - * Andi Kleen : Split fast and slow ip_build_xmit path - * for decreased register pressure on x86 - * and more readibility. - * Marc Boucher : When call_out_firewall returns FW_QUEUE, - * silently drop skb instead of failing with -EPERM. - */ - -#include <asm/uaccess.h> -#include <asm/system.h> -#include <linux/types.h> -#include <linux/kernel.h> -#include <linux/sched.h> -#include <linux/mm.h> -#include <linux/string.h> -#include <linux/errno.h> -#include <linux/config.h> - -#include <linux/socket.h> -#include <linux/sockios.h> -#include <linux/in.h> -#include <linux/inet.h> -#include <linux/netdevice.h> -#include <linux/etherdevice.h> -#include <linux/proc_fs.h> -#include <linux/stat.h> -#include <linux/init.h> - -#include <net/snmp.h> -#include <net/ip.h> -#include <net/protocol.h> -#include <net/route.h> -#include <net/tcp.h> -#include <net/udp.h> -#include <linux/skbuff.h> -#include <net/sock.h> -#include <net/arp.h> -#include <net/icmp.h> -#include <net/raw.h> -#include <net/checksum.h> -#include <linux/igmp.h> -#include <linux/ip_fw.h> -#include <linux/firewall.h> -#include <linux/mroute.h> -#include <linux/netlink.h> - -/* - * Shall we try to damage output packets if routing dev changes? - */ - -int sysctl_ip_dynaddr = 0; - - -int ip_id_count = 0; - -/* Generate a checksum for an outgoing IP datagram. */ -__inline__ void ip_send_check(struct iphdr *iph) -{ - iph->check = 0; - iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl); -} - -/* - * Add an ip header to a skbuff and send it out. - */ -void ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, - u32 saddr, u32 daddr, struct ip_options *opt) -{ - struct rtable *rt = (struct rtable *)skb->dst; - struct iphdr *iph; - struct device *dev; - - /* Build the IP header. */ - if (opt) - iph=(struct iphdr *)skb_push(skb,sizeof(struct iphdr) + opt->optlen); - else - iph=(struct iphdr *)skb_push(skb,sizeof(struct iphdr)); - - iph->version = 4; - iph->ihl = 5; - iph->tos = sk->ip_tos; - iph->frag_off = 0; - if (ip_dont_fragment(sk, &rt->u.dst)) - iph->frag_off |= htons(IP_DF); - iph->ttl = sk->ip_ttl; - iph->daddr = rt->rt_dst; - iph->saddr = rt->rt_src; - iph->protocol = sk->protocol; - iph->tot_len = htons(skb->len); - iph->id = htons(ip_id_count++); - skb->nh.iph = iph; - - if (opt && opt->optlen) { - iph->ihl += opt->optlen>>2; - ip_options_build(skb, opt, daddr, rt, 0); - } - - dev = rt->u.dst.dev; - -#ifdef CONFIG_FIREWALL - /* Now we have no better mechanism to notify about error. */ - switch (call_out_firewall(PF_INET, dev, iph, NULL, &skb)) { - case FW_REJECT: - icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); - /* Fall thru... */ - case FW_BLOCK: - case FW_QUEUE: - kfree_skb(skb); - return; - } -#endif - - ip_send_check(iph); - - /* Send it out. */ - skb->dst->output(skb); - return; -} - -int __ip_finish_output(struct sk_buff *skb) -{ - return ip_finish_output(skb); -} - -int ip_mc_output(struct sk_buff *skb) -{ - struct sock *sk = skb->sk; - struct rtable *rt = (struct rtable*)skb->dst; - struct device *dev = rt->u.dst.dev; - - /* - * If the indicated interface is up and running, send the packet. - */ - - ip_statistics.IpOutRequests++; -#ifdef CONFIG_IP_ROUTE_NAT - if (rt->rt_flags & RTCF_NAT) - ip_do_nat(skb); -#endif - - skb->dev = dev; - skb->protocol = __constant_htons(ETH_P_IP); - - /* - * Multicasts are looped back for other local users - */ - - if (rt->rt_flags&RTCF_MULTICAST && (!sk || sk->ip_mc_loop)) { -#ifdef CONFIG_IP_MROUTE - /* Small optimization: do not loopback not local frames, - which returned after forwarding; they will be dropped - by ip_mr_input in any case. - Note, that local frames are looped back to be delivered - to local recipients. - - This check is duplicated in ip_mr_input at the moment. - */ - if ((rt->rt_flags&RTCF_LOCAL) || !(IPCB(skb)->flags&IPSKB_FORWARDED)) -#endif - dev_loopback_xmit(skb); - - /* Multicasts with ttl 0 must not go beyond the host */ - - if (skb->nh.iph->ttl == 0) { - kfree_skb(skb); - return 0; - } - } - - if (rt->rt_flags&RTCF_BROADCAST) - dev_loopback_xmit(skb); - - return ip_finish_output(skb); -} - -int ip_output(struct sk_buff *skb) -{ - char *str1 = "pfinet ip_output check point 1\n"; - char *str2 = "pfinet ip_output check point 2\n"; - int stderr_fd = fileno (stderr); - int ret; - -#ifdef CONFIG_IP_ROUTE_NAT - struct rtable *rt = (struct rtable*)skb->dst; -#endif - - ip_statistics.IpOutRequests++; - -#ifdef CONFIG_IP_ROUTE_NAT - if (rt->rt_flags&RTCF_NAT) - ip_do_nat(skb); -#endif - - write (stderr_fd, str1, strlen (str1) + 1); - fflush (stderr); - ret = ip_finish_output(skb); - return ret; -} - -/* Queues a packet to be sent, and starts the transmitter if necessary. - * This routine also needs to put in the total length and compute the - * checksum. We use to do this in two stages, ip_build_header() then - * this, but that scheme created a mess when routes disappeared etc. - * So we do it all here, and the TCP send engine has been changed to - * match. (No more unroutable FIN disasters, etc. wheee...) This will - * most likely make other reliable transport layers above IP easier - * to implement under Linux. - */ -void ip_queue_xmit(struct sk_buff *skb) -{ - struct sock *sk = skb->sk; - struct ip_options *opt = sk->opt; - struct rtable *rt; - struct device *dev; - struct iphdr *iph; - unsigned int tot_len; - - /* Make sure we can route this packet. */ - rt = (struct rtable *) sk->dst_cache; - if(rt == NULL || rt->u.dst.obsolete) { - u32 daddr; - - sk->dst_cache = NULL; - ip_rt_put(rt); - - /* Use correct destination address if we have options. */ - daddr = sk->daddr; - if(opt && opt->srr) - daddr = opt->faddr; - - /* If this fails, retransmit mechanism of transport layer will - * keep trying until route appears or the connection times itself - * out. - */ - if(ip_route_output(&rt, daddr, sk->saddr, - RT_TOS(sk->ip_tos) | RTO_CONN | sk->localroute, - sk->bound_dev_if)) - goto drop; - sk->dst_cache = &rt->u.dst; - } - if(opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway) - goto no_route; - - /* We have a route, so grab a reference. */ - skb->dst = dst_clone(sk->dst_cache); - - /* OK, we know where to send it, allocate and build IP header. */ - iph = (struct iphdr *) skb_push(skb, sizeof(struct iphdr) + (opt ? opt->optlen : 0)); - iph->version = 4; - iph->ihl = 5; - iph->tos = sk->ip_tos; - iph->frag_off = 0; - iph->ttl = sk->ip_ttl; - iph->daddr = rt->rt_dst; - iph->saddr = rt->rt_src; - iph->protocol = sk->protocol; - skb->nh.iph = iph; - /* Transport layer set skb->h.foo itself. */ - - if(opt && opt->optlen) { - iph->ihl += opt->optlen >> 2; - ip_options_build(skb, opt, sk->daddr, rt, 0); - } - - tot_len = skb->len; - iph->tot_len = htons(tot_len); - iph->id = htons(ip_id_count++); - - dev = rt->u.dst.dev; - -#ifdef CONFIG_FIREWALL - /* Now we have no better mechanism to notify about error. */ - switch (call_out_firewall(PF_INET, dev, iph, NULL, &skb)) { - case FW_REJECT: - start_bh_atomic(); - icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); - end_bh_atomic(); - /* Fall thru... */ - case FW_BLOCK: - case FW_QUEUE: - goto drop; - } -#endif - - /* This can happen when the transport layer has segments queued - * with a cached route, and by the time we get here things are - * re-routed to a device with a different MTU than the original - * device. Sick, but we must cover it. - */ - if (skb_headroom(skb) < dev->hard_header_len && dev->hard_header) { - struct sk_buff *skb2; - - skb2 = skb_realloc_headroom(skb, (dev->hard_header_len + 15) & ~15); - kfree_skb(skb); - if (skb2 == NULL) - return; - if (sk) - skb_set_owner_w(skb2, sk); - skb = skb2; - iph = skb->nh.iph; - } - - /* Do we need to fragment. Again this is inefficient. We - * need to somehow lock the original buffer and use bits of it. - */ - if (tot_len > rt->u.dst.pmtu) - goto fragment; - - if (ip_dont_fragment(sk, &rt->u.dst)) - iph->frag_off |= __constant_htons(IP_DF); - - /* Add an IP checksum. */ - ip_send_check(iph); - - skb->priority = sk->priority; - skb->dst->output(skb); - return; - -fragment: - if (ip_dont_fragment(sk, &rt->u.dst) && - tot_len > (iph->ihl<<2) + sizeof(struct tcphdr)+16) { - /* Reject packet ONLY if TCP might fragment - it itself, if were careful enough. - Test is not precise (f.e. it does not take sacks - into account). Actually, tcp should make it. --ANK (980801) - */ - iph->frag_off |= __constant_htons(IP_DF); - NETDEBUG(printk(KERN_DEBUG "sending pkt_too_big to self\n")); - - /* icmp_send is not reenterable, so that bh_atomic... --ANK */ - start_bh_atomic(); - icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, - htonl(rt->u.dst.pmtu)); - end_bh_atomic(); - goto drop; - } - ip_fragment(skb, skb->dst->output); - return; - -no_route: - sk->dst_cache = NULL; - ip_rt_put(rt); - ip_statistics.IpOutNoRoutes++; - /* Fall through... */ -drop: - kfree_skb(skb); -} - -/* - * Build and send a packet, with as little as one copy - * - * Doesn't care much about ip options... option length can be - * different for fragment at 0 and other fragments. - * - * Note that the fragment at the highest offset is sent first, - * so the getfrag routine can fill in the TCP/UDP checksum header - * field in the last fragment it sends... actually it also helps - * the reassemblers, they can put most packets in at the head of - * the fragment queue, and they know the total size in advance. This - * last feature will measurably improve the Linux fragment handler one - * day. - * - * The callback has five args, an arbitrary pointer (copy of frag), - * the source IP address (may depend on the routing table), the - * destination address (char *), the offset to copy from, and the - * length to be copied. - */ - -int ip_build_xmit_slow(struct sock *sk, - int getfrag (const void *, - char *, - unsigned int, - unsigned int), - const void *frag, - unsigned length, - struct ipcm_cookie *ipc, - struct rtable *rt, - int flags) -{ - unsigned int fraglen, maxfraglen, fragheaderlen; - int err; - int offset, mf; - int mtu; - unsigned short id; - - int hh_len = (rt->u.dst.dev->hard_header_len + 15)&~15; - int nfrags=0; - struct ip_options *opt = ipc->opt; - int df = 0; - - mtu = rt->u.dst.pmtu; - if (ip_dont_fragment(sk, &rt->u.dst)) - df = htons(IP_DF); - - length -= sizeof(struct iphdr); - - if (opt) { - fragheaderlen = sizeof(struct iphdr) + opt->optlen; - maxfraglen = ((mtu-sizeof(struct iphdr)-opt->optlen) & ~7) + fragheaderlen; - } else { - fragheaderlen = sizeof(struct iphdr); - - /* - * Fragheaderlen is the size of 'overhead' on each buffer. Now work - * out the size of the frames to send. - */ - - maxfraglen = ((mtu-sizeof(struct iphdr)) & ~7) + fragheaderlen; - } - - if (length + fragheaderlen > 0xFFFF) { - ip_local_error(sk, EMSGSIZE, rt->rt_dst, sk->dport, mtu); - return -EMSGSIZE; - } - - /* - * Start at the end of the frame by handling the remainder. - */ - - offset = length - (length % (maxfraglen - fragheaderlen)); - - /* - * Amount of memory to allocate for final fragment. - */ - - fraglen = length - offset + fragheaderlen; - - if (length-offset==0) { - fraglen = maxfraglen; - offset -= maxfraglen-fragheaderlen; - } - - - /* - * The last fragment will not have MF (more fragments) set. - */ - - mf = 0; - - /* - * Don't fragment packets for path mtu discovery. - */ - - if (offset > 0 && df) { - ip_local_error(sk, EMSGSIZE, rt->rt_dst, sk->dport, mtu); - return(-EMSGSIZE); - } - - /* - * Lock the device lists. - */ - - dev_lock_list(); - - /* - * Get an identifier - */ - - id = htons(ip_id_count++); - - /* - * Begin outputting the bytes. - */ - - do { - char *data; - struct sk_buff * skb; - - /* - * Get the memory we require with some space left for alignment. - */ - - skb = sock_alloc_send_skb(sk, fraglen+hh_len+15, 0, flags&MSG_DONTWAIT, &err); - if (skb == NULL) - goto error; - - /* - * Fill in the control structures - */ - - skb->priority = sk->priority; - skb->dst = dst_clone(&rt->u.dst); - skb_reserve(skb, hh_len); - - /* - * Find where to start putting bytes. - */ - - data = skb_put(skb, fraglen); - skb->nh.iph = (struct iphdr *)data; - - /* - * Only write IP header onto non-raw packets - */ - - { - struct iphdr *iph = (struct iphdr *)data; - - iph->version = 4; - iph->ihl = 5; - if (opt) { - iph->ihl += opt->optlen>>2; - ip_options_build(skb, opt, - ipc->addr, rt, offset); - } - iph->tos = sk->ip_tos; - iph->tot_len = htons(fraglen - fragheaderlen + iph->ihl*4); - iph->id = id; - iph->frag_off = htons(offset>>3); - iph->frag_off |= mf|df; - if (rt->rt_type == RTN_MULTICAST) - iph->ttl = sk->ip_mc_ttl; - else - iph->ttl = sk->ip_ttl; - iph->protocol = sk->protocol; - iph->check = 0; - iph->saddr = rt->rt_src; - iph->daddr = rt->rt_dst; - iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl); - data += iph->ihl*4; - - /* - * Any further fragments will have MF set. - */ - - mf = htons(IP_MF); - } - - /* - * User data callback - */ - - if (getfrag(frag, data, offset, fraglen-fragheaderlen)) { - err = -EFAULT; - kfree_skb(skb); - goto error; - } - - offset -= (maxfraglen-fragheaderlen); - fraglen = maxfraglen; - - nfrags++; - -#ifdef CONFIG_FIREWALL - switch (call_out_firewall(PF_INET, rt->u.dst.dev, skb->nh.iph, NULL, &skb)) { - case FW_QUEUE: - kfree_skb(skb); - continue; - case FW_BLOCK: - case FW_REJECT: - kfree_skb(skb); - err = -EPERM; - goto error; - } -#endif - - err = -ENETDOWN; - if (rt->u.dst.output(skb)) - goto error; - } while (offset >= 0); - - if (nfrags>1) - ip_statistics.IpFragCreates += nfrags; - dev_unlock_list(); - return 0; - -error: - ip_statistics.IpOutDiscards++; - if (nfrags>1) - ip_statistics.IpFragCreates += nfrags; - dev_unlock_list(); - return err; -} - - -/* - * Fast path for unfragmented packets. - */ -int ip_build_xmit(struct sock *sk, - int getfrag (const void *, - char *, - unsigned int, - unsigned int), - const void *frag, - unsigned length, - struct ipcm_cookie *ipc, - struct rtable *rt, - int flags) -{ - int err; - struct sk_buff *skb; - int df; - struct iphdr *iph; - - /* - * Try the simple case first. This leaves fragmented frames, and by - * choice RAW frames within 20 bytes of maximum size(rare) to the long path - */ - - if (!sk->ip_hdrincl) { - length += sizeof(struct iphdr); - - /* - * Check for slow path. - */ - if (length > rt->u.dst.pmtu || ipc->opt != NULL) - return ip_build_xmit_slow(sk,getfrag,frag,length,ipc,rt,flags); - } else { - if (length > rt->u.dst.dev->mtu) { - ip_local_error(sk, EMSGSIZE, rt->rt_dst, sk->dport, rt->u.dst.dev->mtu); - return -EMSGSIZE; - } - } - - /* - * Do path mtu discovery if needed. - */ - df = 0; - if (ip_dont_fragment(sk, &rt->u.dst)) - df = htons(IP_DF); - - /* - * Fast path for unfragmented frames without options. - */ - { - int hh_len = (rt->u.dst.dev->hard_header_len + 15)&~15; - - skb = sock_alloc_send_skb(sk, length+hh_len+15, - 0, flags&MSG_DONTWAIT, &err); - if(skb==NULL) - goto error; - skb_reserve(skb, hh_len); - } - - skb->priority = sk->priority; - skb->dst = dst_clone(&rt->u.dst); - - skb->nh.iph = iph = (struct iphdr *)skb_put(skb, length); - - dev_lock_list(); - - if(!sk->ip_hdrincl) { - iph->version=4; - iph->ihl=5; - iph->tos=sk->ip_tos; - iph->tot_len = htons(length); - iph->id=htons(ip_id_count++); - iph->frag_off = df; - iph->ttl=sk->ip_mc_ttl; - if (rt->rt_type != RTN_MULTICAST) - iph->ttl=sk->ip_ttl; - iph->protocol=sk->protocol; - iph->saddr=rt->rt_src; - iph->daddr=rt->rt_dst; - iph->check=0; - iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl); - err = getfrag(frag, ((char *)iph)+iph->ihl*4,0, length-iph->ihl*4); - } - else - err = getfrag(frag, (void *)iph, 0, length); - - dev_unlock_list(); - - if (err) - goto error_fault; - -#ifdef CONFIG_FIREWALL - switch (call_out_firewall(PF_INET, rt->u.dst.dev, iph, NULL, &skb)) { - case FW_QUEUE: - kfree_skb(skb); - return 0; - case FW_BLOCK: - case FW_REJECT: - kfree_skb(skb); - err = -EPERM; - goto error; - } -#endif - - return rt->u.dst.output(skb); - -error_fault: - err = -EFAULT; - kfree_skb(skb); -error: - ip_statistics.IpOutDiscards++; - return err; -} - - - -/* - * This IP datagram is too large to be sent in one piece. Break it up into - * smaller pieces (each of size equal to IP header plus - * a block of the data of the original IP data part) that will yet fit in a - * single device frame, and queue such a frame for sending. - * - * Yes this is inefficient, feel free to submit a quicker one. - */ - -void ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff*)) -{ - struct iphdr *iph; - unsigned char *raw; - unsigned char *ptr; - struct device *dev; - struct sk_buff *skb2; - unsigned int mtu, hlen, left, len; - int offset; - int not_last_frag; - struct rtable *rt = (struct rtable*)skb->dst; - - dev = rt->u.dst.dev; - - /* - * Point into the IP datagram header. - */ - - raw = skb->nh.raw; - iph = (struct iphdr*)raw; - - /* - * Setup starting values. - */ - - hlen = iph->ihl * 4; - left = ntohs(iph->tot_len) - hlen; /* Space per frame */ - mtu = rt->u.dst.pmtu - hlen; /* Size of data space */ - ptr = raw + hlen; /* Where to start from */ - - /* - * The protocol doesn't seem to say what to do in the case that the - * frame + options doesn't fit the mtu. As it used to fall down dead - * in this case we were fortunate it didn't happen - * - * It is impossible, because mtu>=68. --ANK (980801) - */ - -#ifdef CONFIG_NET_PARANOIA - if (mtu<8) - goto fail; -#endif - - /* - * Fragment the datagram. - */ - - offset = (ntohs(iph->frag_off) & IP_OFFSET) << 3; - not_last_frag = iph->frag_off & htons(IP_MF); - - /* - * Keep copying data until we run out. - */ - - while(left > 0) { - len = left; - /* IF: it doesn't fit, use 'mtu' - the data space left */ - if (len > mtu) - len = mtu; - /* IF: we are not sending upto and including the packet end - then align the next start on an eight byte boundary */ - if (len < left) { - len &= ~7; - } - /* - * Allocate buffer. - */ - - if ((skb2 = alloc_skb(len+hlen+dev->hard_header_len+15,GFP_ATOMIC)) == NULL) { - NETDEBUG(printk(KERN_INFO "IP: frag: no memory for new fragment!\n")); - goto fail; - } - - /* - * Set up data on packet - */ - - skb2->pkt_type = skb->pkt_type; - skb2->priority = skb->priority; - skb_reserve(skb2, (dev->hard_header_len+15)&~15); - skb_put(skb2, len + hlen); - skb2->nh.raw = skb2->data; - skb2->h.raw = skb2->data + hlen; - - /* - * Charge the memory for the fragment to any owner - * it might possess - */ - - if (skb->sk) - skb_set_owner_w(skb2, skb->sk); - skb2->dst = dst_clone(skb->dst); - - /* - * Copy the packet header into the new buffer. - */ - - memcpy(skb2->nh.raw, raw, hlen); - - /* - * Copy a block of the IP datagram. - */ - memcpy(skb2->h.raw, ptr, len); - left -= len; - - /* - * Fill in the new header fields. - */ - iph = skb2->nh.iph; - iph->frag_off = htons((offset >> 3)); - - /* ANK: dirty, but effective trick. Upgrade options only if - * the segment to be fragmented was THE FIRST (otherwise, - * options are already fixed) and make it ONCE - * on the initial skb, so that all the following fragments - * will inherit fixed options. - */ - if (offset == 0) - ip_options_fragment(skb); - - /* - * Added AC : If we are fragmenting a fragment that's not the - * last fragment then keep MF on each bit - */ - if (left > 0 || not_last_frag) - iph->frag_off |= htons(IP_MF); - ptr += len; - offset += len; - - /* - * Put this fragment into the sending queue. - */ - - ip_statistics.IpFragCreates++; - - iph->tot_len = htons(len + hlen); - - ip_send_check(iph); - - output(skb2); - } - kfree_skb(skb); - ip_statistics.IpFragOKs++; - return; - -fail: - kfree_skb(skb); - ip_statistics.IpFragFails++; -} - -/* - * Fetch data from kernel space and fill in checksum if needed. - */ -static int ip_reply_glue_bits(const void *dptr, char *to, unsigned int offset, - unsigned int fraglen) -{ - struct ip_reply_arg *dp = (struct ip_reply_arg*)dptr; - u16 *pktp = (u16 *)to; - struct iovec *iov; - int len; - int hdrflag = 1; - - iov = &dp->iov[0]; - if (offset >= iov->iov_len) { - offset -= iov->iov_len; - iov++; - hdrflag = 0; - } - len = iov->iov_len - offset; - if (fraglen > len) { /* overlapping. */ - dp->csum = csum_partial_copy_nocheck(iov->iov_base+offset, to, len, - dp->csum); - offset = 0; - fraglen -= len; - to += len; - iov++; - } - - dp->csum = csum_partial_copy_nocheck(iov->iov_base+offset, to, fraglen, - dp->csum); - - if (hdrflag && dp->csumoffset) - *(pktp + dp->csumoffset) = csum_fold(dp->csum); /* fill in checksum */ - return 0; -} - -/* - * Generic function to send a packet as reply to another packet. - * Used to send TCP resets so far. ICMP should use this function too. - * - * Should run single threaded per socket because it uses the sock - * structure to pass arguments. - */ -void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *arg, - unsigned int len) -{ - struct { - struct ip_options opt; - char data[40]; - } replyopts; - struct ipcm_cookie ipc; - u32 daddr; - struct rtable *rt = (struct rtable*)skb->dst; - - if (ip_options_echo(&replyopts.opt, skb)) - return; - - sk->ip_tos = skb->nh.iph->tos; - sk->priority = skb->priority; - sk->protocol = skb->nh.iph->protocol; - - daddr = ipc.addr = rt->rt_src; - ipc.opt = &replyopts.opt; - - if (ipc.opt->srr) - daddr = replyopts.opt.faddr; - if (ip_route_output(&rt, daddr, rt->rt_spec_dst, RT_TOS(skb->nh.iph->tos), 0)) - return; - - /* And let IP do all the hard work. */ - ip_build_xmit(sk, ip_reply_glue_bits, arg, len, &ipc, rt, MSG_DONTWAIT); - ip_rt_put(rt); -} - -/* - * IP protocol layer initialiser - */ - -static struct packet_type ip_packet_type = -{ - __constant_htons(ETH_P_IP), - NULL, /* All devices */ - ip_rcv, - NULL, - NULL, -}; - - - -#ifdef CONFIG_PROC_FS -#ifdef CONFIG_IP_MULTICAST -static struct proc_dir_entry proc_net_igmp = { - PROC_NET_IGMP, 4, "igmp", - S_IFREG | S_IRUGO, 1, 0, 0, - 0, &proc_net_inode_operations, - ip_mc_procinfo -}; -#endif -#endif - -/* - * IP registers the packet type and then calls the subprotocol initialisers - */ - -__initfunc(void ip_init(void)) -{ - dev_add_pack(&ip_packet_type); - - ip_rt_init(); - -#ifdef CONFIG_PROC_FS -#ifdef CONFIG_IP_MULTICAST - proc_net_register(&proc_net_igmp); -#endif -#endif -} - |