| /* |
| * 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 User Datagram Protocol (UDP). |
| * |
| * Version: $Id: udp.c,v 1.101 2002-01-12 07:39:45 davem Exp $ |
| * |
| * Authors: Ross Biro, <bir7@leland.Stanford.Edu> |
| * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
| * Arnt Gulbrandsen, <agulbra@nvg.unit.no> |
| * Alan Cox, <Alan.Cox@linux.org> |
| * |
| * Fixes: |
| * Alan Cox : verify_area() calls |
| * Alan Cox : stopped close while in use off icmp |
| * messages. Not a fix but a botch that |
| * for udp at least is 'valid'. |
| * Alan Cox : Fixed icmp handling properly |
| * Alan Cox : Correct error for oversized datagrams |
| * Alan Cox : Tidied select() semantics. |
| * Alan Cox : udp_err() fixed properly, also now |
| * select and read wake correctly on errors |
| * Alan Cox : udp_send verify_area moved to avoid mem leak |
| * Alan Cox : UDP can count its memory |
| * Alan Cox : send to an unknown connection causes |
| * an ECONNREFUSED off the icmp, but |
| * does NOT close. |
| * Alan Cox : Switched to new sk_buff handlers. No more backlog! |
| * Alan Cox : Using generic datagram code. Even smaller and the PEEK |
| * bug no longer crashes it. |
| * Fred Van Kempen : Net2e support for sk->broadcast. |
| * Alan Cox : Uses skb_free_datagram |
| * Alan Cox : Added get/set sockopt support. |
| * Alan Cox : Broadcasting without option set returns EACCES. |
| * Alan Cox : No wakeup calls. Instead we now use the callbacks. |
| * Alan Cox : Use ip_tos and ip_ttl |
| * Alan Cox : SNMP Mibs |
| * Alan Cox : MSG_DONTROUTE, and 0.0.0.0 support. |
| * Matt Dillon : UDP length checks. |
| * Alan Cox : Smarter af_inet used properly. |
| * Alan Cox : Use new kernel side addressing. |
| * Alan Cox : Incorrect return on truncated datagram receive. |
| * Arnt Gulbrandsen : New udp_send and stuff |
| * Alan Cox : Cache last socket |
| * Alan Cox : Route cache |
| * Jon Peatfield : Minor efficiency fix to sendto(). |
| * Mike Shaver : RFC1122 checks. |
| * Alan Cox : Nonblocking error fix. |
| * Willy Konynenberg : Transparent proxying support. |
| * Mike McLagan : Routing by source |
| * David S. Miller : New socket lookup architecture. |
| * Last socket cache retained as it |
| * does have a high hit rate. |
| * Olaf Kirch : Don't linearise iovec on sendmsg. |
| * Andi Kleen : Some cleanups, cache destination entry |
| * for connect. |
| * Vitaly E. Lavrov : Transparent proxy revived after year coma. |
| * Melvin Smith : Check msg_name not msg_namelen in sendto(), |
| * return ENOTCONN for unconnected sockets (POSIX) |
| * Janos Farkas : don't deliver multi/broadcasts to a different |
| * bound-to-device socket |
| * |
| * |
| * 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 <asm/system.h> |
| #include <asm/uaccess.h> |
| #include <asm/ioctls.h> |
| #include <linux/types.h> |
| #include <linux/fcntl.h> |
| #include <linux/socket.h> |
| #include <linux/sockios.h> |
| #include <linux/in.h> |
| #include <linux/errno.h> |
| #include <linux/timer.h> |
| #include <linux/mm.h> |
| #include <linux/config.h> |
| #include <linux/inet.h> |
| #include <linux/netdevice.h> |
| #include <net/snmp.h> |
| #include <net/ip.h> |
| #include <net/protocol.h> |
| #include <linux/skbuff.h> |
| #include <net/sock.h> |
| #include <net/udp.h> |
| #include <net/icmp.h> |
| #include <net/route.h> |
| #include <net/inet_common.h> |
| #include <net/checksum.h> |
| |
| /* |
| * Snmp MIB for the UDP layer |
| */ |
| |
| struct udp_mib udp_statistics[NR_CPUS*2]; |
| |
| struct sock *udp_hash[UDP_HTABLE_SIZE]; |
| rwlock_t udp_hash_lock = RW_LOCK_UNLOCKED; |
| |
| /* Shared by v4/v6 udp. */ |
| int udp_port_rover; |
| |
| static int udp_v4_get_port(struct sock *sk, unsigned short snum) |
| { |
| write_lock_bh(&udp_hash_lock); |
| if (snum == 0) { |
| int best_size_so_far, best, result, i; |
| |
| if (udp_port_rover > sysctl_local_port_range[1] || |
| udp_port_rover < sysctl_local_port_range[0]) |
| udp_port_rover = sysctl_local_port_range[0]; |
| best_size_so_far = 32767; |
| best = result = udp_port_rover; |
| for (i = 0; i < UDP_HTABLE_SIZE; i++, result++) { |
| struct sock *sk; |
| int size; |
| |
| sk = udp_hash[result & (UDP_HTABLE_SIZE - 1)]; |
| if (!sk) { |
| if (result > sysctl_local_port_range[1]) |
| result = sysctl_local_port_range[0] + |
| ((result - sysctl_local_port_range[0]) & |
| (UDP_HTABLE_SIZE - 1)); |
| goto gotit; |
| } |
| size = 0; |
| do { |
| if (++size >= best_size_so_far) |
| goto next; |
| } while ((sk = sk->next) != NULL); |
| best_size_so_far = size; |
| best = result; |
| next:; |
| } |
| result = best; |
| for(i = 0; i < (1 << 16) / UDP_HTABLE_SIZE; i++, result += UDP_HTABLE_SIZE) { |
| if (result > sysctl_local_port_range[1]) |
| result = sysctl_local_port_range[0] |
| + ((result - sysctl_local_port_range[0]) & |
| (UDP_HTABLE_SIZE - 1)); |
| if (!udp_lport_inuse(result)) |
| break; |
| } |
| if (i >= (1 << 16) / UDP_HTABLE_SIZE) |
| goto fail; |
| gotit: |
| udp_port_rover = snum = result; |
| } else { |
| struct sock *sk2; |
| |
| for (sk2 = udp_hash[snum & (UDP_HTABLE_SIZE - 1)]; |
| sk2 != NULL; |
| sk2 = sk2->next) { |
| if (sk2->num == snum && |
| sk2 != sk && |
| sk2->bound_dev_if == sk->bound_dev_if && |
| (!sk2->rcv_saddr || |
| !sk->rcv_saddr || |
| sk2->rcv_saddr == sk->rcv_saddr) && |
| (!sk2->reuse || !sk->reuse)) |
| goto fail; |
| } |
| } |
| sk->num = snum; |
| if (sk->pprev == NULL) { |
| struct sock **skp = &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]; |
| if ((sk->next = *skp) != NULL) |
| (*skp)->pprev = &sk->next; |
| *skp = sk; |
| sk->pprev = skp; |
| sock_prot_inc_use(sk->prot); |
| sock_hold(sk); |
| } |
| write_unlock_bh(&udp_hash_lock); |
| return 0; |
| |
| fail: |
| write_unlock_bh(&udp_hash_lock); |
| return 1; |
| } |
| |
| static void udp_v4_hash(struct sock *sk) |
| { |
| BUG(); |
| } |
| |
| static void udp_v4_unhash(struct sock *sk) |
| { |
| write_lock_bh(&udp_hash_lock); |
| if (sk->pprev) { |
| if (sk->next) |
| sk->next->pprev = sk->pprev; |
| *sk->pprev = sk->next; |
| sk->pprev = NULL; |
| sk->num = 0; |
| sock_prot_dec_use(sk->prot); |
| __sock_put(sk); |
| } |
| write_unlock_bh(&udp_hash_lock); |
| } |
| |
| /* UDP is nearly always wildcards out the wazoo, it makes no sense to try |
| * harder than this. -DaveM |
| */ |
| struct sock *udp_v4_lookup_longway(u32 saddr, u16 sport, u32 daddr, u16 dport, int dif) |
| { |
| struct sock *sk, *result = NULL; |
| unsigned short hnum = ntohs(dport); |
| int badness = -1; |
| |
| for(sk = udp_hash[hnum & (UDP_HTABLE_SIZE - 1)]; sk != NULL; sk = sk->next) { |
| if(sk->num == hnum) { |
| int score = 0; |
| if(sk->rcv_saddr) { |
| if(sk->rcv_saddr != daddr) |
| continue; |
| score++; |
| } |
| if(sk->daddr) { |
| if(sk->daddr != saddr) |
| continue; |
| score++; |
| } |
| if(sk->dport) { |
| if(sk->dport != sport) |
| continue; |
| score++; |
| } |
| if(sk->bound_dev_if) { |
| if(sk->bound_dev_if != dif) |
| continue; |
| score++; |
| } |
| if(score == 4) { |
| result = sk; |
| break; |
| } else if(score > badness) { |
| result = sk; |
| badness = score; |
| } |
| } |
| } |
| return result; |
| } |
| |
| __inline__ struct sock *udp_v4_lookup(u32 saddr, u16 sport, u32 daddr, u16 dport, int dif) |
| { |
| struct sock *sk; |
| |
| read_lock(&udp_hash_lock); |
| sk = udp_v4_lookup_longway(saddr, sport, daddr, dport, dif); |
| if (sk) |
| sock_hold(sk); |
| read_unlock(&udp_hash_lock); |
| return sk; |
| } |
| |
| static inline struct sock *udp_v4_mcast_next(struct sock *sk, |
| u16 loc_port, u32 loc_addr, |
| u16 rmt_port, u32 rmt_addr, |
| int dif) |
| { |
| struct sock *s = sk; |
| unsigned short hnum = ntohs(loc_port); |
| for(; s; s = s->next) { |
| if ((s->num != hnum) || |
| (s->daddr && s->daddr!=rmt_addr) || |
| (s->dport != rmt_port && s->dport != 0) || |
| (s->rcv_saddr && s->rcv_saddr != loc_addr) || |
| (s->bound_dev_if && s->bound_dev_if != dif)) |
| continue; |
| break; |
| } |
| return s; |
| } |
| |
| /* |
| * This routine is called by the ICMP module when it gets some |
| * sort of error condition. If err < 0 then the socket should |
| * be closed and the error returned to the user. If err > 0 |
| * it's just the icmp type << 8 | icmp code. |
| * Header points to the ip header of the error packet. We move |
| * on past this. Then (as it used to claim before adjustment) |
| * header points to the first 8 bytes of the udp header. We need |
| * to find the appropriate port. |
| */ |
| |
| void udp_err(struct sk_buff *skb, u32 info) |
| { |
| struct iphdr *iph = (struct iphdr*)skb->data; |
| struct udphdr *uh = (struct udphdr*)(skb->data+(iph->ihl<<2)); |
| int type = skb->h.icmph->type; |
| int code = skb->h.icmph->code; |
| struct sock *sk; |
| int harderr; |
| int err; |
| |
| sk = udp_v4_lookup(iph->daddr, uh->dest, iph->saddr, uh->source, skb->dev->ifindex); |
| if (sk == NULL) { |
| ICMP_INC_STATS_BH(IcmpInErrors); |
| return; /* No socket for error */ |
| } |
| |
| err = 0; |
| harderr = 0; |
| |
| switch (type) { |
| default: |
| case ICMP_TIME_EXCEEDED: |
| err = EHOSTUNREACH; |
| break; |
| case ICMP_SOURCE_QUENCH: |
| goto out; |
| case ICMP_PARAMETERPROB: |
| err = EPROTO; |
| harderr = 1; |
| break; |
| case ICMP_DEST_UNREACH: |
| if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */ |
| if (sk->protinfo.af_inet.pmtudisc != IP_PMTUDISC_DONT) { |
| err = EMSGSIZE; |
| harderr = 1; |
| break; |
| } |
| goto out; |
| } |
| err = EHOSTUNREACH; |
| if (code <= NR_ICMP_UNREACH) { |
| harderr = icmp_err_convert[code].fatal; |
| err = icmp_err_convert[code].errno; |
| } |
| break; |
| } |
| |
| /* |
| * RFC1122: OK. Passes ICMP errors back to application, as per |
| * 4.1.3.3. |
| */ |
| if (!sk->protinfo.af_inet.recverr) { |
| if (!harderr || sk->state != TCP_ESTABLISHED) |
| goto out; |
| } else { |
| ip_icmp_error(sk, skb, err, uh->dest, info, (u8*)(uh+1)); |
| } |
| sk->err = err; |
| sk->error_report(sk); |
| out: |
| sock_put(sk); |
| } |
| |
| |
| static unsigned short udp_check(struct udphdr *uh, int len, unsigned long saddr, unsigned long daddr, unsigned long base) |
| { |
| return(csum_tcpudp_magic(saddr, daddr, len, IPPROTO_UDP, base)); |
| } |
| |
| struct udpfakehdr |
| { |
| struct udphdr uh; |
| u32 saddr; |
| u32 daddr; |
| struct iovec *iov; |
| u32 wcheck; |
| }; |
| |
| /* |
| * Copy and checksum a UDP packet from user space into a buffer. |
| */ |
| |
| static int udp_getfrag(const void *p, char * to, unsigned int offset, unsigned int fraglen) |
| { |
| struct udpfakehdr *ufh = (struct udpfakehdr *)p; |
| if (offset==0) { |
| if (csum_partial_copy_fromiovecend(to+sizeof(struct udphdr), ufh->iov, offset, |
| fraglen-sizeof(struct udphdr), &ufh->wcheck)) |
| return -EFAULT; |
| ufh->wcheck = csum_partial((char *)ufh, sizeof(struct udphdr), |
| ufh->wcheck); |
| ufh->uh.check = csum_tcpudp_magic(ufh->saddr, ufh->daddr, |
| ntohs(ufh->uh.len), |
| IPPROTO_UDP, ufh->wcheck); |
| if (ufh->uh.check == 0) |
| ufh->uh.check = -1; |
| memcpy(to, ufh, sizeof(struct udphdr)); |
| return 0; |
| } |
| if (csum_partial_copy_fromiovecend(to, ufh->iov, offset-sizeof(struct udphdr), |
| fraglen, &ufh->wcheck)) |
| return -EFAULT; |
| return 0; |
| } |
| |
| /* |
| * Copy a UDP packet from user space into a buffer without checksumming. |
| */ |
| |
| static int udp_getfrag_nosum(const void *p, char * to, unsigned int offset, unsigned int fraglen) |
| { |
| struct udpfakehdr *ufh = (struct udpfakehdr *)p; |
| |
| if (offset==0) { |
| memcpy(to, ufh, sizeof(struct udphdr)); |
| return memcpy_fromiovecend(to+sizeof(struct udphdr), ufh->iov, offset, |
| fraglen-sizeof(struct udphdr)); |
| } |
| return memcpy_fromiovecend(to, ufh->iov, offset-sizeof(struct udphdr), |
| fraglen); |
| } |
| |
| int udp_sendmsg(struct sock *sk, struct msghdr *msg, int len) |
| { |
| int ulen = len + sizeof(struct udphdr); |
| struct ipcm_cookie ipc; |
| struct udpfakehdr ufh; |
| struct rtable *rt = NULL; |
| int free = 0; |
| int connected = 0; |
| u32 daddr; |
| u8 tos; |
| int err; |
| |
| /* This check is ONLY to check for arithmetic overflow |
| on integer(!) len. Not more! Real check will be made |
| in ip_build_xmit --ANK |
| |
| BTW socket.c -> af_*.c -> ... make multiple |
| invalid conversions size_t -> int. We MUST repair it f.e. |
| by replacing all of them with size_t and revise all |
| the places sort of len += sizeof(struct iphdr) |
| If len was ULONG_MAX-10 it would be cathastrophe --ANK |
| */ |
| |
| if (len < 0 || len > 0xFFFF) |
| return -EMSGSIZE; |
| |
| /* |
| * Check the flags. |
| */ |
| |
| if (msg->msg_flags&MSG_OOB) /* Mirror BSD error message compatibility */ |
| return -EOPNOTSUPP; |
| |
| /* |
| * Get and verify the address. |
| */ |
| |
| if (msg->msg_name) { |
| struct sockaddr_in * usin = (struct sockaddr_in*)msg->msg_name; |
| if (msg->msg_namelen < sizeof(*usin)) |
| return -EINVAL; |
| if (usin->sin_family != AF_INET) { |
| if (usin->sin_family != AF_UNSPEC) |
| return -EINVAL; |
| } |
| |
| ufh.daddr = usin->sin_addr.s_addr; |
| ufh.uh.dest = usin->sin_port; |
| if (ufh.uh.dest == 0) |
| return -EINVAL; |
| } else { |
| if (sk->state != TCP_ESTABLISHED) |
| return -ENOTCONN; |
| ufh.daddr = sk->daddr; |
| ufh.uh.dest = sk->dport; |
| /* Open fast path for connected socket. |
| Route will not be used, if at least one option is set. |
| */ |
| connected = 1; |
| } |
| ipc.addr = sk->saddr; |
| ufh.uh.source = sk->sport; |
| |
| ipc.opt = NULL; |
| ipc.oif = sk->bound_dev_if; |
| if (msg->msg_controllen) { |
| err = ip_cmsg_send(msg, &ipc); |
| if (err) |
| return err; |
| if (ipc.opt) |
| free = 1; |
| connected = 0; |
| } |
| if (!ipc.opt) |
| ipc.opt = sk->protinfo.af_inet.opt; |
| |
| ufh.saddr = ipc.addr; |
| ipc.addr = daddr = ufh.daddr; |
| |
| if (ipc.opt && ipc.opt->srr) { |
| if (!daddr) |
| return -EINVAL; |
| daddr = ipc.opt->faddr; |
| connected = 0; |
| } |
| tos = RT_TOS(sk->protinfo.af_inet.tos); |
| if (sk->localroute || (msg->msg_flags&MSG_DONTROUTE) || |
| (ipc.opt && ipc.opt->is_strictroute)) { |
| tos |= RTO_ONLINK; |
| connected = 0; |
| } |
| |
| if (MULTICAST(daddr)) { |
| if (!ipc.oif) |
| ipc.oif = sk->protinfo.af_inet.mc_index; |
| if (!ufh.saddr) |
| ufh.saddr = sk->protinfo.af_inet.mc_addr; |
| connected = 0; |
| } |
| |
| if (connected) |
| rt = (struct rtable*)sk_dst_check(sk, 0); |
| |
| if (rt == NULL) { |
| err = ip_route_output(&rt, daddr, ufh.saddr, tos, ipc.oif); |
| if (err) |
| goto out; |
| |
| err = -EACCES; |
| if (rt->rt_flags&RTCF_BROADCAST && !sk->broadcast) |
| goto out; |
| if (connected) |
| sk_dst_set(sk, dst_clone(&rt->u.dst)); |
| } |
| |
| if (msg->msg_flags&MSG_CONFIRM) |
| goto do_confirm; |
| back_from_confirm: |
| |
| ufh.saddr = rt->rt_src; |
| if (!ipc.addr) |
| ufh.daddr = ipc.addr = rt->rt_dst; |
| ufh.uh.len = htons(ulen); |
| ufh.uh.check = 0; |
| ufh.iov = msg->msg_iov; |
| ufh.wcheck = 0; |
| |
| /* RFC1122: OK. Provides the checksumming facility (MUST) as per */ |
| /* 4.1.3.4. It's configurable by the application via setsockopt() */ |
| /* (MAY) and it defaults to on (MUST). */ |
| |
| err = ip_build_xmit(sk, |
| (sk->no_check == UDP_CSUM_NOXMIT ? |
| udp_getfrag_nosum : |
| udp_getfrag), |
| &ufh, ulen, &ipc, rt, msg->msg_flags); |
| |
| out: |
| ip_rt_put(rt); |
| if (free) |
| kfree(ipc.opt); |
| if (!err) { |
| UDP_INC_STATS_USER(UdpOutDatagrams); |
| return len; |
| } |
| return err; |
| |
| do_confirm: |
| dst_confirm(&rt->u.dst); |
| if (!(msg->msg_flags&MSG_PROBE) || len) |
| goto back_from_confirm; |
| err = 0; |
| goto out; |
| } |
| |
| /* |
| * IOCTL requests applicable to the UDP protocol |
| */ |
| |
| int udp_ioctl(struct sock *sk, int cmd, unsigned long arg) |
| { |
| switch(cmd) |
| { |
| case SIOCOUTQ: |
| { |
| int amount = atomic_read(&sk->wmem_alloc); |
| return put_user(amount, (int *)arg); |
| } |
| |
| case SIOCINQ: |
| { |
| struct sk_buff *skb; |
| unsigned long amount; |
| |
| amount = 0; |
| spin_lock_irq(&sk->receive_queue.lock); |
| skb = skb_peek(&sk->receive_queue); |
| if (skb != NULL) { |
| /* |
| * We will only return the amount |
| * of this packet since that is all |
| * that will be read. |
| */ |
| amount = skb->len - sizeof(struct udphdr); |
| } |
| spin_unlock_irq(&sk->receive_queue.lock); |
| return put_user(amount, (int *)arg); |
| } |
| |
| default: |
| return -ENOIOCTLCMD; |
| } |
| return(0); |
| } |
| |
| static __inline__ int __udp_checksum_complete(struct sk_buff *skb) |
| { |
| return (unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum)); |
| } |
| |
| static __inline__ int udp_checksum_complete(struct sk_buff *skb) |
| { |
| return skb->ip_summed != CHECKSUM_UNNECESSARY && |
| __udp_checksum_complete(skb); |
| } |
| |
| /* |
| * This should be easy, if there is something there we |
| * return it, otherwise we block. |
| */ |
| |
| int udp_recvmsg(struct sock *sk, struct msghdr *msg, int len, |
| int noblock, int flags, int *addr_len) |
| { |
| struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name; |
| struct sk_buff *skb; |
| int copied, err; |
| |
| /* |
| * Check any passed addresses |
| */ |
| if (addr_len) |
| *addr_len=sizeof(*sin); |
| |
| if (flags & MSG_ERRQUEUE) |
| return ip_recv_error(sk, msg, len); |
| |
| skb = skb_recv_datagram(sk, flags, noblock, &err); |
| if (!skb) |
| goto out; |
| |
| copied = skb->len - sizeof(struct udphdr); |
| if (copied > len) { |
| copied = len; |
| msg->msg_flags |= MSG_TRUNC; |
| } |
| |
| if (skb->ip_summed==CHECKSUM_UNNECESSARY) { |
| err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov, |
| copied); |
| } else if (msg->msg_flags&MSG_TRUNC) { |
| if (__udp_checksum_complete(skb)) |
| goto csum_copy_err; |
| err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov, |
| copied); |
| } else { |
| err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov); |
| |
| if (err == -EINVAL) |
| goto csum_copy_err; |
| } |
| |
| if (err) |
| goto out_free; |
| |
| sock_recv_timestamp(msg, sk, skb); |
| |
| /* Copy the address. */ |
| if (sin) |
| { |
| sin->sin_family = AF_INET; |
| sin->sin_port = skb->h.uh->source; |
| sin->sin_addr.s_addr = skb->nh.iph->saddr; |
| memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); |
| } |
| if (sk->protinfo.af_inet.cmsg_flags) |
| ip_cmsg_recv(msg, skb); |
| err = copied; |
| |
| out_free: |
| skb_free_datagram(sk, skb); |
| out: |
| return err; |
| |
| csum_copy_err: |
| UDP_INC_STATS_BH(UdpInErrors); |
| |
| /* Clear queue. */ |
| if (flags&MSG_PEEK) { |
| int clear = 0; |
| spin_lock_irq(&sk->receive_queue.lock); |
| if (skb == skb_peek(&sk->receive_queue)) { |
| __skb_unlink(skb, &sk->receive_queue); |
| clear = 1; |
| } |
| spin_unlock_irq(&sk->receive_queue.lock); |
| if (clear) |
| kfree_skb(skb); |
| } |
| |
| skb_free_datagram(sk, skb); |
| |
| return -EAGAIN; |
| } |
| |
| int udp_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) |
| { |
| struct sockaddr_in *usin = (struct sockaddr_in *) uaddr; |
| struct rtable *rt; |
| int err; |
| |
| |
| if (addr_len < sizeof(*usin)) |
| return -EINVAL; |
| |
| if (usin->sin_family != AF_INET) |
| return -EAFNOSUPPORT; |
| |
| sk_dst_reset(sk); |
| |
| err = ip_route_connect(&rt, usin->sin_addr.s_addr, sk->saddr, |
| RT_CONN_FLAGS(sk), sk->bound_dev_if); |
| if (err) |
| return err; |
| if ((rt->rt_flags&RTCF_BROADCAST) && !sk->broadcast) { |
| ip_rt_put(rt); |
| return -EACCES; |
| } |
| if(!sk->saddr) |
| sk->saddr = rt->rt_src; /* Update source address */ |
| if(!sk->rcv_saddr) |
| sk->rcv_saddr = rt->rt_src; |
| sk->daddr = rt->rt_dst; |
| sk->dport = usin->sin_port; |
| sk->state = TCP_ESTABLISHED; |
| sk->protinfo.af_inet.id = jiffies; |
| |
| sk_dst_set(sk, &rt->u.dst); |
| return(0); |
| } |
| |
| int udp_disconnect(struct sock *sk, int flags) |
| { |
| /* |
| * 1003.1g - break association. |
| */ |
| |
| sk->state = TCP_CLOSE; |
| sk->daddr = 0; |
| sk->dport = 0; |
| sk->bound_dev_if = 0; |
| if (!(sk->userlocks&SOCK_BINDADDR_LOCK)) { |
| sk->rcv_saddr = 0; |
| sk->saddr = 0; |
| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| memset(&sk->net_pinfo.af_inet6.saddr, 0, 16); |
| memset(&sk->net_pinfo.af_inet6.rcv_saddr, 0, 16); |
| #endif |
| } |
| if (!(sk->userlocks&SOCK_BINDPORT_LOCK)) { |
| sk->prot->unhash(sk); |
| sk->sport = 0; |
| } |
| sk_dst_reset(sk); |
| return 0; |
| } |
| |
| static void udp_close(struct sock *sk, long timeout) |
| { |
| inet_sock_release(sk); |
| } |
| |
| static int udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb) |
| { |
| /* |
| * Charge it to the socket, dropping if the queue is full. |
| */ |
| |
| #if defined(CONFIG_FILTER) |
| if (sk->filter && skb->ip_summed != CHECKSUM_UNNECESSARY) { |
| if (__udp_checksum_complete(skb)) { |
| UDP_INC_STATS_BH(UdpInErrors); |
| IP_INC_STATS_BH(IpInDiscards); |
| ip_statistics[smp_processor_id()*2].IpInDelivers--; |
| kfree_skb(skb); |
| return -1; |
| } |
| skb->ip_summed = CHECKSUM_UNNECESSARY; |
| } |
| #endif |
| |
| if (sock_queue_rcv_skb(sk,skb)<0) { |
| UDP_INC_STATS_BH(UdpInErrors); |
| IP_INC_STATS_BH(IpInDiscards); |
| ip_statistics[smp_processor_id()*2].IpInDelivers--; |
| kfree_skb(skb); |
| return -1; |
| } |
| UDP_INC_STATS_BH(UdpInDatagrams); |
| return 0; |
| } |
| |
| /* |
| * Multicasts and broadcasts go to each listener. |
| * |
| * Note: called only from the BH handler context, |
| * so we don't need to lock the hashes. |
| */ |
| static int udp_v4_mcast_deliver(struct sk_buff *skb, struct udphdr *uh, |
| u32 saddr, u32 daddr) |
| { |
| struct sock *sk; |
| int dif; |
| |
| read_lock(&udp_hash_lock); |
| sk = udp_hash[ntohs(uh->dest) & (UDP_HTABLE_SIZE - 1)]; |
| dif = skb->dev->ifindex; |
| sk = udp_v4_mcast_next(sk, uh->dest, daddr, uh->source, saddr, dif); |
| if (sk) { |
| struct sock *sknext = NULL; |
| |
| do { |
| struct sk_buff *skb1 = skb; |
| |
| sknext = udp_v4_mcast_next(sk->next, uh->dest, daddr, |
| uh->source, saddr, dif); |
| if(sknext) |
| skb1 = skb_clone(skb, GFP_ATOMIC); |
| |
| if(skb1) |
| udp_queue_rcv_skb(sk, skb1); |
| sk = sknext; |
| } while(sknext); |
| } else |
| kfree_skb(skb); |
| read_unlock(&udp_hash_lock); |
| return 0; |
| } |
| |
| /* Initialize UDP checksum. If exited with zero value (success), |
| * CHECKSUM_UNNECESSARY means, that no more checks are required. |
| * Otherwise, csum completion requires chacksumming packet body, |
| * including udp header and folding it to skb->csum. |
| */ |
| static int udp_checksum_init(struct sk_buff *skb, struct udphdr *uh, |
| unsigned short ulen, u32 saddr, u32 daddr) |
| { |
| if (uh->check == 0) { |
| skb->ip_summed = CHECKSUM_UNNECESSARY; |
| } else if (skb->ip_summed == CHECKSUM_HW) { |
| skb->ip_summed = CHECKSUM_UNNECESSARY; |
| if (!udp_check(uh, ulen, saddr, daddr, skb->csum)) |
| return 0; |
| NETDEBUG(if (net_ratelimit()) printk(KERN_DEBUG "udp v4 hw csum failure.\n")); |
| skb->ip_summed = CHECKSUM_NONE; |
| } |
| if (skb->ip_summed != CHECKSUM_UNNECESSARY) |
| skb->csum = csum_tcpudp_nofold(saddr, daddr, ulen, IPPROTO_UDP, 0); |
| /* Probably, we should checksum udp header (it should be in cache |
| * in any case) and data in tiny packets (< rx copybreak). |
| */ |
| return 0; |
| } |
| |
| /* |
| * All we need to do is get the socket, and then do a checksum. |
| */ |
| |
| int udp_rcv(struct sk_buff *skb) |
| { |
| struct sock *sk; |
| struct udphdr *uh; |
| unsigned short ulen; |
| struct rtable *rt = (struct rtable*)skb->dst; |
| u32 saddr = skb->nh.iph->saddr; |
| u32 daddr = skb->nh.iph->daddr; |
| int len = skb->len; |
| |
| IP_INC_STATS_BH(IpInDelivers); |
| |
| /* |
| * Validate the packet and the UDP length. |
| */ |
| if (!pskb_may_pull(skb, sizeof(struct udphdr))) |
| goto no_header; |
| |
| ulen = ntohs(skb->h.uh->len); |
| |
| if (ulen > len || ulen < sizeof(*uh)) |
| goto short_packet; |
| |
| if (pskb_trim(skb, ulen)) |
| goto short_packet; |
| |
| uh = skb->h.uh; |
| |
| if (udp_checksum_init(skb, uh, ulen, saddr, daddr) < 0) |
| goto csum_error; |
| |
| if(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST)) |
| return udp_v4_mcast_deliver(skb, uh, saddr, daddr); |
| |
| sk = udp_v4_lookup(saddr, uh->source, daddr, uh->dest, skb->dev->ifindex); |
| |
| if (sk != NULL) { |
| udp_queue_rcv_skb(sk, skb); |
| sock_put(sk); |
| return 0; |
| } |
| |
| /* No socket. Drop packet silently, if checksum is wrong */ |
| if (udp_checksum_complete(skb)) |
| goto csum_error; |
| |
| UDP_INC_STATS_BH(UdpNoPorts); |
| icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); |
| |
| /* |
| * Hmm. We got an UDP packet to a port to which we |
| * don't wanna listen. Ignore it. |
| */ |
| kfree_skb(skb); |
| return(0); |
| |
| short_packet: |
| NETDEBUG(if (net_ratelimit()) printk(KERN_DEBUG "UDP: short packet: %d/%d\n", ulen, len)); |
| no_header: |
| UDP_INC_STATS_BH(UdpInErrors); |
| kfree_skb(skb); |
| return(0); |
| |
| csum_error: |
| /* |
| * RFC1122: OK. Discards the bad packet silently (as far as |
| * the network is concerned, anyway) as per 4.1.3.4 (MUST). |
| */ |
| NETDEBUG(if (net_ratelimit()) |
| printk(KERN_DEBUG "UDP: bad checksum. From %d.%d.%d.%d:%d to %d.%d.%d.%d:%d ulen %d\n", |
| NIPQUAD(saddr), |
| ntohs(uh->source), |
| NIPQUAD(daddr), |
| ntohs(uh->dest), |
| ulen)); |
| UDP_INC_STATS_BH(UdpInErrors); |
| kfree_skb(skb); |
| return(0); |
| } |
| |
| static void get_udp_sock(struct sock *sp, char *tmpbuf, int i) |
| { |
| unsigned int dest, src; |
| __u16 destp, srcp; |
| |
| dest = sp->daddr; |
| src = sp->rcv_saddr; |
| destp = ntohs(sp->dport); |
| srcp = ntohs(sp->sport); |
| sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X" |
| " %02X %08X:%08X %02X:%08lX %08X %5d %8d %ld %d %p", |
| i, src, srcp, dest, destp, sp->state, |
| atomic_read(&sp->wmem_alloc), atomic_read(&sp->rmem_alloc), |
| 0, 0L, 0, |
| sock_i_uid(sp), 0, |
| sock_i_ino(sp), |
| atomic_read(&sp->refcnt), sp); |
| } |
| |
| int udp_get_info(char *buffer, char **start, off_t offset, int length) |
| { |
| int len = 0, num = 0, i; |
| off_t pos = 0; |
| off_t begin; |
| char tmpbuf[129]; |
| |
| if (offset < 128) |
| len += sprintf(buffer, "%-127s\n", |
| " sl local_address rem_address st tx_queue " |
| "rx_queue tr tm->when retrnsmt uid timeout inode"); |
| pos = 128; |
| read_lock(&udp_hash_lock); |
| for (i = 0; i < UDP_HTABLE_SIZE; i++) { |
| struct sock *sk; |
| |
| for (sk = udp_hash[i]; sk; sk = sk->next, num++) { |
| if (sk->family != PF_INET) |
| continue; |
| pos += 128; |
| if (pos <= offset) |
| continue; |
| get_udp_sock(sk, tmpbuf, i); |
| len += sprintf(buffer+len, "%-127s\n", tmpbuf); |
| if(len >= length) |
| goto out; |
| } |
| } |
| out: |
| read_unlock(&udp_hash_lock); |
| begin = len - (pos - offset); |
| *start = buffer + begin; |
| len -= begin; |
| if(len > length) |
| len = length; |
| if (len < 0) |
| len = 0; |
| return len; |
| } |
| |
| struct proto udp_prot = { |
| name: "UDP", |
| close: udp_close, |
| connect: udp_connect, |
| disconnect: udp_disconnect, |
| ioctl: udp_ioctl, |
| setsockopt: ip_setsockopt, |
| getsockopt: ip_getsockopt, |
| sendmsg: udp_sendmsg, |
| recvmsg: udp_recvmsg, |
| backlog_rcv: udp_queue_rcv_skb, |
| hash: udp_v4_hash, |
| unhash: udp_v4_unhash, |
| get_port: udp_v4_get_port, |
| }; |