datagram.c
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上传日期:2013-02-24
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文件大小:11k
- /*
- * common UDP/RAW code
- * Linux INET6 implementation
- *
- * Authors:
- * Pedro Roque <roque@di.fc.ul.pt>
- *
- * $Id: datagram.c,v 1.23 2001/09/01 00:31:50 davem Exp $
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
- #include <linux/errno.h>
- #include <linux/types.h>
- #include <linux/kernel.h>
- #include <linux/sched.h>
- #include <linux/interrupt.h>
- #include <linux/socket.h>
- #include <linux/sockios.h>
- #include <linux/in6.h>
- #include <linux/ipv6.h>
- #include <linux/route.h>
- #include <net/ipv6.h>
- #include <net/ndisc.h>
- #include <net/addrconf.h>
- #include <net/transp_v6.h>
- #include <linux/errqueue.h>
- #include <asm/uaccess.h>
- void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
- u16 port, u32 info, u8 *payload)
- {
- struct icmp6hdr *icmph = (struct icmp6hdr *)skb->h.raw;
- struct sock_exterr_skb *serr;
- if (!sk->net_pinfo.af_inet6.recverr)
- return;
- skb = skb_clone(skb, GFP_ATOMIC);
- if (!skb)
- return;
- serr = SKB_EXT_ERR(skb);
- serr->ee.ee_errno = err;
- serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
- serr->ee.ee_type = icmph->icmp6_type;
- serr->ee.ee_code = icmph->icmp6_code;
- serr->ee.ee_pad = 0;
- serr->ee.ee_info = info;
- serr->ee.ee_data = 0;
- serr->addr_offset = (u8*)&(((struct ipv6hdr*)(icmph+1))->daddr) - skb->nh.raw;
- serr->port = port;
- skb->h.raw = payload;
- __skb_pull(skb, payload - skb->data);
- if (sock_queue_err_skb(sk, skb))
- kfree_skb(skb);
- }
- void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info)
- {
- struct sock_exterr_skb *serr;
- struct ipv6hdr *iph;
- struct sk_buff *skb;
- if (!sk->net_pinfo.af_inet6.recverr)
- return;
- skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
- if (!skb)
- return;
- iph = (struct ipv6hdr*)skb_put(skb, sizeof(struct ipv6hdr));
- skb->nh.ipv6h = iph;
- memcpy(&iph->daddr, fl->fl6_dst, 16);
- serr = SKB_EXT_ERR(skb);
- serr->ee.ee_errno = err;
- serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
- serr->ee.ee_type = 0;
- serr->ee.ee_code = 0;
- serr->ee.ee_pad = 0;
- serr->ee.ee_info = info;
- serr->ee.ee_data = 0;
- serr->addr_offset = (u8*)&iph->daddr - skb->nh.raw;
- serr->port = fl->uli_u.ports.dport;
- skb->h.raw = skb->tail;
- __skb_pull(skb, skb->tail - skb->data);
- if (sock_queue_err_skb(sk, skb))
- kfree_skb(skb);
- }
- /*
- * Handle MSG_ERRQUEUE
- */
- int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
- {
- struct sock_exterr_skb *serr;
- struct sk_buff *skb, *skb2;
- struct sockaddr_in6 *sin;
- struct {
- struct sock_extended_err ee;
- struct sockaddr_in6 offender;
- } errhdr;
- int err;
- int copied;
- err = -EAGAIN;
- skb = skb_dequeue(&sk->error_queue);
- if (skb == NULL)
- goto out;
- copied = skb->len;
- if (copied > len) {
- msg->msg_flags |= MSG_TRUNC;
- copied = len;
- }
- err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
- if (err)
- goto out_free_skb;
- sock_recv_timestamp(msg, sk, skb);
- serr = SKB_EXT_ERR(skb);
- sin = (struct sockaddr_in6 *)msg->msg_name;
- if (sin) {
- sin->sin6_family = AF_INET6;
- sin->sin6_flowinfo = 0;
- sin->sin6_port = serr->port;
- sin->sin6_scope_id = 0;
- if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
- memcpy(&sin->sin6_addr, skb->nh.raw + serr->addr_offset, 16);
- if (sk->net_pinfo.af_inet6.sndflow)
- sin->sin6_flowinfo = *(u32*)(skb->nh.raw + serr->addr_offset - 24) & IPV6_FLOWINFO_MASK;
- if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
- struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
- sin->sin6_scope_id = opt->iif;
- }
- } else {
- ipv6_addr_set(&sin->sin6_addr, 0, 0,
- __constant_htonl(0xffff),
- *(u32*)(skb->nh.raw + serr->addr_offset));
- }
- }
- memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
- sin = &errhdr.offender;
- sin->sin6_family = AF_UNSPEC;
- if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
- sin->sin6_family = AF_INET6;
- sin->sin6_flowinfo = 0;
- if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
- memcpy(&sin->sin6_addr, &skb->nh.ipv6h->saddr, 16);
- if (sk->net_pinfo.af_inet6.rxopt.all)
- datagram_recv_ctl(sk, msg, skb);
- if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL) {
- struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
- sin->sin6_scope_id = opt->iif;
- }
- } else {
- ipv6_addr_set(&sin->sin6_addr, 0, 0,
- __constant_htonl(0xffff),
- skb->nh.iph->saddr);
- if (sk->protinfo.af_inet.cmsg_flags)
- ip_cmsg_recv(msg, skb);
- }
- }
- put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
- /* Now we could try to dump offended packet options */
- msg->msg_flags |= MSG_ERRQUEUE;
- err = copied;
- /* Reset and regenerate socket error */
- spin_lock_irq(&sk->error_queue.lock);
- sk->err = 0;
- if ((skb2 = skb_peek(&sk->error_queue)) != NULL) {
- sk->err = SKB_EXT_ERR(skb2)->ee.ee_errno;
- spin_unlock_irq(&sk->error_queue.lock);
- sk->error_report(sk);
- } else {
- spin_unlock_irq(&sk->error_queue.lock);
- }
- out_free_skb:
- kfree_skb(skb);
- out:
- return err;
- }
- int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
- {
- struct ipv6_pinfo *np = &sk->net_pinfo.af_inet6;
- struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb;
- if (np->rxopt.bits.rxinfo) {
- struct in6_pktinfo src_info;
- src_info.ipi6_ifindex = opt->iif;
- ipv6_addr_copy(&src_info.ipi6_addr, &skb->nh.ipv6h->daddr);
- put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
- }
- if (np->rxopt.bits.rxhlim) {
- int hlim = skb->nh.ipv6h->hop_limit;
- put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
- }
- if (np->rxopt.bits.rxflow && (*(u32*)skb->nh.raw & IPV6_FLOWINFO_MASK)) {
- u32 flowinfo = *(u32*)skb->nh.raw & IPV6_FLOWINFO_MASK;
- put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
- }
- if (np->rxopt.bits.hopopts && opt->hop) {
- u8 *ptr = skb->nh.raw + opt->hop;
- put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
- }
- if (np->rxopt.bits.dstopts && opt->dst0) {
- u8 *ptr = skb->nh.raw + opt->dst0;
- put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, (ptr[1]+1)<<3, ptr);
- }
- if (np->rxopt.bits.srcrt && opt->srcrt) {
- struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(skb->nh.raw + opt->srcrt);
- put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
- }
- if (np->rxopt.bits.authhdr && opt->auth) {
- u8 *ptr = skb->nh.raw + opt->auth;
- put_cmsg(msg, SOL_IPV6, IPV6_AUTHHDR, (ptr[1]+1)<<2, ptr);
- }
- if (np->rxopt.bits.dstopts && opt->dst1) {
- u8 *ptr = skb->nh.raw + opt->dst1;
- put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, (ptr[1]+1)<<3, ptr);
- }
- return 0;
- }
- int datagram_send_ctl(struct msghdr *msg, struct flowi *fl,
- struct ipv6_txoptions *opt,
- int *hlimit)
- {
- struct in6_pktinfo *src_info;
- struct cmsghdr *cmsg;
- struct ipv6_rt_hdr *rthdr;
- struct ipv6_opt_hdr *hdr;
- int len;
- int err = 0;
- for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
- if (cmsg->cmsg_len < sizeof(struct cmsghdr) ||
- (unsigned long)(((char*)cmsg - (char*)msg->msg_control)
- + cmsg->cmsg_len) > msg->msg_controllen) {
- err = -EINVAL;
- goto exit_f;
- }
- if (cmsg->cmsg_level != SOL_IPV6)
- continue;
- switch (cmsg->cmsg_type) {
- case IPV6_PKTINFO:
- if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
- err = -EINVAL;
- goto exit_f;
- }
- src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
-
- if (src_info->ipi6_ifindex) {
- if (fl->oif && src_info->ipi6_ifindex != fl->oif)
- return -EINVAL;
- fl->oif = src_info->ipi6_ifindex;
- }
- if (!ipv6_addr_any(&src_info->ipi6_addr)) {
- if (!ipv6_chk_addr(&src_info->ipi6_addr, NULL)) {
- err = -EINVAL;
- goto exit_f;
- }
- fl->fl6_src = &src_info->ipi6_addr;
- }
- break;
- case IPV6_FLOWINFO:
- if (cmsg->cmsg_len < CMSG_LEN(4)) {
- err = -EINVAL;
- goto exit_f;
- }
- if (fl->fl6_flowlabel&IPV6_FLOWINFO_MASK) {
- if ((fl->fl6_flowlabel^*(u32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
- err = -EINVAL;
- goto exit_f;
- }
- }
- fl->fl6_flowlabel = IPV6_FLOWINFO_MASK & *(u32 *)CMSG_DATA(cmsg);
- break;
- case IPV6_HOPOPTS:
- if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
- err = -EINVAL;
- goto exit_f;
- }
- hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
- len = ((hdr->hdrlen + 1) << 3);
- if (cmsg->cmsg_len < CMSG_LEN(len)) {
- err = -EINVAL;
- goto exit_f;
- }
- if (!capable(CAP_NET_RAW)) {
- err = -EPERM;
- goto exit_f;
- }
- opt->opt_nflen += len;
- opt->hopopt = hdr;
- break;
- case IPV6_DSTOPTS:
- if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
- err = -EINVAL;
- goto exit_f;
- }
- hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
- len = ((hdr->hdrlen + 1) << 3);
- if (cmsg->cmsg_len < CMSG_LEN(len)) {
- err = -EINVAL;
- goto exit_f;
- }
- if (!capable(CAP_NET_RAW)) {
- err = -EPERM;
- goto exit_f;
- }
- if (opt->dst1opt) {
- err = -EINVAL;
- goto exit_f;
- }
- opt->opt_flen += len;
- opt->dst1opt = hdr;
- break;
- case IPV6_AUTHHDR:
- if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
- err = -EINVAL;
- goto exit_f;
- }
- hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
- len = ((hdr->hdrlen + 2) << 2);
- if (cmsg->cmsg_len < CMSG_LEN(len)) {
- err = -EINVAL;
- goto exit_f;
- }
- if (len & ~7) {
- err = -EINVAL;
- goto exit_f;
- }
- opt->opt_flen += len;
- opt->auth = hdr;
- break;
- case IPV6_RTHDR:
- if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
- err = -EINVAL;
- goto exit_f;
- }
- rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
- /*
- * TYPE 0
- */
- if (rthdr->type) {
- err = -EINVAL;
- goto exit_f;
- }
- len = ((rthdr->hdrlen + 1) << 3);
- if (cmsg->cmsg_len < CMSG_LEN(len)) {
- err = -EINVAL;
- goto exit_f;
- }
- /* segments left must also match */
- if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
- err = -EINVAL;
- goto exit_f;
- }
- opt->opt_nflen += len;
- opt->srcrt = rthdr;
- if (opt->dst1opt) {
- int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
- opt->opt_nflen += dsthdrlen;
- opt->dst0opt = opt->dst1opt;
- opt->dst1opt = NULL;
- opt->opt_flen -= dsthdrlen;
- }
- break;
- case IPV6_HOPLIMIT:
- if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
- err = -EINVAL;
- goto exit_f;
- }
- *hlimit = *(int *)CMSG_DATA(cmsg);
- break;
- default:
- if (net_ratelimit())
- printk(KERN_DEBUG "invalid cmsg type: %dn", cmsg->cmsg_type);
- err = -EINVAL;
- break;
- };
- }
- exit_f:
- return err;
- }