extractedLnx/linux-2.6.14/net/ipv4/ip_sockglue.c_ip_setsockopt.c

int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval, int optlen)
{
	struct inet_sock *inet = inet_sk(sk);
	int val=0,err;

	if (level != SOL_IP)
		return -ENOPROTOOPT;

	if (((1<<optname) & ((1<<IP_PKTINFO) | (1<<IP_RECVTTL) | 
			    (1<<IP_RECVOPTS) | (1<<IP_RECVTOS) | 
			    (1<<IP_RETOPTS) | (1<<IP_TOS) | 
			    (1<<IP_TTL) | (1<<IP_HDRINCL) | 
			    (1<<IP_MTU_DISCOVER) | (1<<IP_RECVERR) | 
			    (1<<IP_ROUTER_ALERT) | (1<<IP_FREEBIND))) || 
				optname == IP_MULTICAST_TTL || 
				optname == IP_MULTICAST_LOOP) { 
		if (optlen >= sizeof(int)) {
			if (get_user(val, (int __user *) optval))
				return -EFAULT;
		} else if (optlen >= sizeof(char)) {
			unsigned char ucval;

			if (get_user(ucval, (unsigned char __user *) optval))
				return -EFAULT;
			val = (int) ucval;
		}
	}

	/* If optlen==0, it is equivalent to val == 0 */

#ifdef CONFIG_IP_MROUTE
	if (optname >= MRT_BASE && optname <= (MRT_BASE + 10))
		return ip_mroute_setsockopt(sk,optname,optval,optlen);
#endif

	err = 0;
	lock_sock(sk);

	switch (optname) {
		case IP_OPTIONS:
		{
			struct ip_options * opt = NULL;
			if (optlen > 40 || optlen < 0)
				goto e_inval;
			err = ip_options_get_from_user(&opt, optval, optlen);
			if (err)
				break;
			if (sk->sk_type == SOCK_STREAM) {
				struct tcp_sock *tp = tcp_sk(sk);
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
				if (sk->sk_family == PF_INET ||
				    (!((1 << sk->sk_state) &
				       (TCPF_LISTEN | TCPF_CLOSE)) &&
				     inet->daddr != LOOPBACK4_IPV6)) {
#endif
					if (inet->opt)
						tp->ext_header_len -= inet->opt->optlen;
					if (opt)
						tp->ext_header_len += opt->optlen;
					tcp_sync_mss(sk, tp->pmtu_cookie);
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
				}
#endif
			}
			opt = xchg(&inet->opt, opt);
			if (opt)
				kfree(opt);
			break;
		}
		case IP_PKTINFO:
			if (val)
				inet->cmsg_flags |= IP_CMSG_PKTINFO;
			else
				inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
			break;
		case IP_RECVTTL:
			if (val)
				inet->cmsg_flags |=  IP_CMSG_TTL;
			else
				inet->cmsg_flags &= ~IP_CMSG_TTL;
			break;
		case IP_RECVTOS:
			if (val)
				inet->cmsg_flags |=  IP_CMSG_TOS;
			else
				inet->cmsg_flags &= ~IP_CMSG_TOS;
			break;
		case IP_RECVOPTS:
			if (val)
				inet->cmsg_flags |=  IP_CMSG_RECVOPTS;
			else
				inet->cmsg_flags &= ~IP_CMSG_RECVOPTS;
			break;
		case IP_RETOPTS:
			if (val)
				inet->cmsg_flags |= IP_CMSG_RETOPTS;
			else
				inet->cmsg_flags &= ~IP_CMSG_RETOPTS;
			break;
		case IP_TOS:	/* This sets both TOS and Precedence */
			if (sk->sk_type == SOCK_STREAM) {
				val &= ~3;
				val |= inet->tos & 3;
			}
			if (IPTOS_PREC(val) >= IPTOS_PREC_CRITIC_ECP && 
			    !capable(CAP_NET_ADMIN)) {
				err = -EPERM;
				break;
			}
			if (inet->tos != val) {
				inet->tos = val;
				sk->sk_priority = rt_tos2priority(val);
				sk_dst_reset(sk); 
			}
			break;
		case IP_TTL:
			if (optlen<1)
				goto e_inval;
			if (val != -1 && (val < 1 || val>255))
				goto e_inval;
			inet->uc_ttl = val;
			break;
		case IP_HDRINCL:
			if (sk->sk_type != SOCK_RAW) {
				err = -ENOPROTOOPT;
				break;
			}
			inet->hdrincl = val ? 1 : 0;
			break;
		case IP_MTU_DISCOVER:
			if (val<0 || val>2)
				goto e_inval;
			inet->pmtudisc = val;
			break;
		case IP_RECVERR:
			inet->recverr = !!val;
			if (!val)
				skb_queue_purge(&sk->sk_error_queue);
			break;
		case IP_MULTICAST_TTL:
			if (sk->sk_type == SOCK_STREAM)
				goto e_inval;
			if (optlen<1)
				goto e_inval;
			if (val==-1)
				val = 1;
			if (val < 0 || val > 255)
				goto e_inval;
			inet->mc_ttl = val;
	                break;
		case IP_MULTICAST_LOOP: 
			if (optlen<1)
				goto e_inval;
			inet->mc_loop = !!val;
	                break;
		case IP_MULTICAST_IF: 
		{
			struct ip_mreqn mreq;
			struct net_device *dev = NULL;

			if (sk->sk_type == SOCK_STREAM)
				goto e_inval;
			/*
			 *	Check the arguments are allowable
			 */

			err = -EFAULT;
			if (optlen >= sizeof(struct ip_mreqn)) {
				if (copy_from_user(&mreq,optval,sizeof(mreq)))
					break;
			} else {
				memset(&mreq, 0, sizeof(mreq));
				if (optlen >= sizeof(struct in_addr) &&
				    copy_from_user(&mreq.imr_address,optval,sizeof(struct in_addr)))
					break;
			}

			if (!mreq.imr_ifindex) {
				if (mreq.imr_address.s_addr == INADDR_ANY) {
					inet->mc_index = 0;
					inet->mc_addr  = 0;
					err = 0;
					break;
				}
				dev = ip_dev_find(mreq.imr_address.s_addr);
				if (dev) {
					mreq.imr_ifindex = dev->ifindex;
					dev_put(dev);
				}
			} else
				dev = __dev_get_by_index(mreq.imr_ifindex);


			err = -EADDRNOTAVAIL;
			if (!dev)
				break;

			err = -EINVAL;
			if (sk->sk_bound_dev_if &&
			    mreq.imr_ifindex != sk->sk_bound_dev_if)
				break;

			inet->mc_index = mreq.imr_ifindex;
			inet->mc_addr  = mreq.imr_address.s_addr;
			err = 0;
			break;
		}

		case IP_ADD_MEMBERSHIP:
		case IP_DROP_MEMBERSHIP: 
		{
			struct ip_mreqn mreq;

			if (optlen < sizeof(struct ip_mreq))
				goto e_inval;
			err = -EFAULT;
			if (optlen >= sizeof(struct ip_mreqn)) {
				if(copy_from_user(&mreq,optval,sizeof(mreq)))
					break;
			} else {
				memset(&mreq, 0, sizeof(mreq));
				if (copy_from_user(&mreq,optval,sizeof(struct ip_mreq)))
					break; 
			}

			if (optname == IP_ADD_MEMBERSHIP)
				err = ip_mc_join_group(sk, &mreq);
			else
				err = ip_mc_leave_group(sk, &mreq);
			break;
		}
		case IP_MSFILTER:
		{
			extern int sysctl_igmp_max_msf;
			struct ip_msfilter *msf;

			if (optlen < IP_MSFILTER_SIZE(0))
				goto e_inval;
			if (optlen > sysctl_optmem_max) {
				err = -ENOBUFS;
				break;
			}
			msf = (struct ip_msfilter *)kmalloc(optlen, GFP_KERNEL);
			if (msf == 0) {
				err = -ENOBUFS;
				break;
			}
			err = -EFAULT;
			if (copy_from_user(msf, optval, optlen)) {
				kfree(msf);
				break;
			}
			/* numsrc >= (1G-4) overflow in 32 bits */
			if (msf->imsf_numsrc >= 0x3ffffffcU ||
			    msf->imsf_numsrc > sysctl_igmp_max_msf) {
				kfree(msf);
				err = -ENOBUFS;
				break;
			}
			if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {
				kfree(msf);
				err = -EINVAL;
				break;
			}
			err = ip_mc_msfilter(sk, msf, 0);
			kfree(msf);
			break;
		}
		case IP_BLOCK_SOURCE:
		case IP_UNBLOCK_SOURCE:
		case IP_ADD_SOURCE_MEMBERSHIP:
		case IP_DROP_SOURCE_MEMBERSHIP:
		{
			struct ip_mreq_source mreqs;
			int omode, add;

			if (optlen != sizeof(struct ip_mreq_source))
				goto e_inval;
			if (copy_from_user(&mreqs, optval, sizeof(mreqs))) {
				err = -EFAULT;
				break;
			}
			if (optname == IP_BLOCK_SOURCE) {
				omode = MCAST_EXCLUDE;
				add = 1;
			} else if (optname == IP_UNBLOCK_SOURCE) {
				omode = MCAST_EXCLUDE;
				add = 0;
			} else if (optname == IP_ADD_SOURCE_MEMBERSHIP) {
				struct ip_mreqn mreq;

				mreq.imr_multiaddr.s_addr = mreqs.imr_multiaddr;
				mreq.imr_address.s_addr = mreqs.imr_interface;
				mreq.imr_ifindex = 0;
				err = ip_mc_join_group(sk, &mreq);
				if (err && err != -EADDRINUSE)
					break;
				omode = MCAST_INCLUDE;
				add = 1;
			} else /* IP_DROP_SOURCE_MEMBERSHIP */ {
				omode = MCAST_INCLUDE;
				add = 0;
			}
			err = ip_mc_source(add, omode, sk, &mreqs, 0);
			break;
		}
		case MCAST_JOIN_GROUP:
		case MCAST_LEAVE_GROUP: 
		{
			struct group_req greq;
			struct sockaddr_in *psin;
			struct ip_mreqn mreq;

			if (optlen < sizeof(struct group_req))
				goto e_inval;
			err = -EFAULT;
			if(copy_from_user(&greq, optval, sizeof(greq)))
				break;
			psin = (struct sockaddr_in *)&greq.gr_group;
			if (psin->sin_family != AF_INET)
				goto e_inval;
			memset(&mreq, 0, sizeof(mreq));
			mreq.imr_multiaddr = psin->sin_addr;
			mreq.imr_ifindex = greq.gr_interface;

			if (optname == MCAST_JOIN_GROUP)
				err = ip_mc_join_group(sk, &mreq);
			else
				err = ip_mc_leave_group(sk, &mreq);
			break;
		}
		case MCAST_JOIN_SOURCE_GROUP:
		case MCAST_LEAVE_SOURCE_GROUP:
		case MCAST_BLOCK_SOURCE:
		case MCAST_UNBLOCK_SOURCE:
		{
			struct group_source_req greqs;
			struct ip_mreq_source mreqs;
			struct sockaddr_in *psin;
			int omode, add;

			if (optlen != sizeof(struct group_source_req))
				goto e_inval;
			if (copy_from_user(&greqs, optval, sizeof(greqs))) {
				err = -EFAULT;
				break;
			}
			if (greqs.gsr_group.ss_family != AF_INET ||
			    greqs.gsr_source.ss_family != AF_INET) {
				err = -EADDRNOTAVAIL;
				break;
			}
			psin = (struct sockaddr_in *)&greqs.gsr_group;
			mreqs.imr_multiaddr = psin->sin_addr.s_addr;
			psin = (struct sockaddr_in *)&greqs.gsr_source;
			mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
			mreqs.imr_interface = 0; /* use index for mc_source */

			if (optname == MCAST_BLOCK_SOURCE) {
				omode = MCAST_EXCLUDE;
				add = 1;
			} else if (optname == MCAST_UNBLOCK_SOURCE) {
				omode = MCAST_EXCLUDE;
				add = 0;
			} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
				struct ip_mreqn mreq;

				psin = (struct sockaddr_in *)&greqs.gsr_group;
				mreq.imr_multiaddr = psin->sin_addr;
				mreq.imr_address.s_addr = 0;
				mreq.imr_ifindex = greqs.gsr_interface;
				err = ip_mc_join_group(sk, &mreq);
				if (err && err != -EADDRINUSE)
					break;
				greqs.gsr_interface = mreq.imr_ifindex;
				omode = MCAST_INCLUDE;
				add = 1;
			} else /* MCAST_LEAVE_SOURCE_GROUP */ {
				omode = MCAST_INCLUDE;
				add = 0;
			}
			err = ip_mc_source(add, omode, sk, &mreqs,
				greqs.gsr_interface);
			break;
		}
		case MCAST_MSFILTER:
		{
			extern int sysctl_igmp_max_msf;
			struct sockaddr_in *psin;
			struct ip_msfilter *msf = NULL;
			struct group_filter *gsf = NULL;
			int msize, i, ifindex;

			if (optlen < GROUP_FILTER_SIZE(0))
				goto e_inval;
			if (optlen > sysctl_optmem_max) {
				err = -ENOBUFS;
				break;
			}
			gsf = (struct group_filter *)kmalloc(optlen,GFP_KERNEL);
			if (gsf == 0) {
				err = -ENOBUFS;
				break;
			}
			err = -EFAULT;
			if (copy_from_user(gsf, optval, optlen)) {
				goto mc_msf_out;
			}
			/* numsrc >= (4G-140)/128 overflow in 32 bits */
			if (gsf->gf_numsrc >= 0x1ffffff ||
			    gsf->gf_numsrc > sysctl_igmp_max_msf) {
				err = -ENOBUFS;
				goto mc_msf_out;
			}
			if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen) {
				err = -EINVAL;
				goto mc_msf_out;
			}
			msize = IP_MSFILTER_SIZE(gsf->gf_numsrc);
			msf = (struct ip_msfilter *)kmalloc(msize,GFP_KERNEL);
			if (msf == 0) {
				err = -ENOBUFS;
				goto mc_msf_out;
			}
			ifindex = gsf->gf_interface;
			psin = (struct sockaddr_in *)&gsf->gf_group;
			if (psin->sin_family != AF_INET) {
				err = -EADDRNOTAVAIL;
				goto mc_msf_out;
			}
			msf->imsf_multiaddr = psin->sin_addr.s_addr;
			msf->imsf_interface = 0;
			msf->imsf_fmode = gsf->gf_fmode;
			msf->imsf_numsrc = gsf->gf_numsrc;
			err = -EADDRNOTAVAIL;
			for (i=0; i<gsf->gf_numsrc; ++i) {
				psin = (struct sockaddr_in *)&gsf->gf_slist[i];

				if (psin->sin_family != AF_INET)
					goto mc_msf_out;
				msf->imsf_slist[i] = psin->sin_addr.s_addr;
			}
			kfree(gsf);
			gsf = NULL;

			err = ip_mc_msfilter(sk, msf, ifindex);
mc_msf_out:
			if (msf)
				kfree(msf);
			if (gsf)
				kfree(gsf);
			break;
		}
		case IP_ROUTER_ALERT:	
			err = ip_ra_control(sk, val ? 1 : 0, NULL);
			break;

		case IP_FREEBIND:
			if (optlen<1)
				goto e_inval;
			inet->freebind = !!val; 
	                break;			
 
		case IP_IPSEC_POLICY:
		case IP_XFRM_POLICY:
			err = -EPERM;
			if (!capable(CAP_NET_ADMIN))
				break;
			err = xfrm_user_policy(sk, optname, optval, optlen);
			break;

		default:
#ifdef CONFIG_NETFILTER
			err = nf_setsockopt(sk, PF_INET, optname, optval, 
					    optlen);
#else
			err = -ENOPROTOOPT;
#endif
			break;
	}
	release_sock(sk);
	return err;

e_inval:
	release_sock(sk);
	return -EINVAL;
}