From ba4e58eca8aa9473b44fdfd312f26c4a2e7798b3 Mon Sep 17 00:00:00 2001 From: Gerrit Renker Date: Mon, 27 Nov 2006 11:10:57 -0800 Subject: [NET]: Supporting UDP-Lite (RFC 3828) in Linux This is a revision of the previously submitted patch, which alters the way files are organized and compiled in the following manner: * UDP and UDP-Lite now use separate object files * source file dependencies resolved via header files net/ipv{4,6}/udp_impl.h * order of inclusion files in udp.c/udplite.c adapted accordingly [NET/IPv4]: Support for the UDP-Lite protocol (RFC 3828) This patch adds support for UDP-Lite to the IPv4 stack, provided as an extension to the existing UDPv4 code: * generic routines are all located in net/ipv4/udp.c * UDP-Lite specific routines are in net/ipv4/udplite.c * MIB/statistics support in /proc/net/snmp and /proc/net/udplite * shared API with extensions for partial checksum coverage [NET/IPv6]: Extension for UDP-Lite over IPv6 It extends the existing UDPv6 code base with support for UDP-Lite in the same manner as per UDPv4. In particular, * UDPv6 generic and shared code is in net/ipv6/udp.c * UDP-Litev6 specific extensions are in net/ipv6/udplite.c * MIB/statistics support in /proc/net/snmp6 and /proc/net/udplite6 * support for IPV6_ADDRFORM * aligned the coding style of protocol initialisation with af_inet6.c * made the error handling in udpv6_queue_rcv_skb consistent; to return `-1' on error on all error cases * consolidation of shared code [NET]: UDP-Lite Documentation and basic XFRM/Netfilter support The UDP-Lite patch further provides * API documentation for UDP-Lite * basic xfrm support * basic netfilter support for IPv4 and IPv6 (LOG target) Signed-off-by: Gerrit Renker Signed-off-by: David S. Miller --- net/ipv4/udp.c | 518 +++++++++++++++++++++++++++++++++------------------------ 1 file changed, 300 insertions(+), 218 deletions(-) (limited to 'net/ipv4/udp.c') diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 9e1bd374875..98ba7509617 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -92,22 +92,16 @@ #include #include #include -#include #include -#include -#include #include -#include #include #include #include -#include -#include #include #include -#include #include #include +#include "udp_impl.h" /* * Snmp MIB for the UDP layer @@ -120,26 +114,30 @@ DEFINE_RWLOCK(udp_hash_lock); static int udp_port_rover; -static inline int udp_lport_inuse(u16 num) +static inline int __udp_lib_lport_inuse(__be16 num, struct hlist_head udptable[]) { struct sock *sk; struct hlist_node *node; - sk_for_each(sk, node, &udp_hash[num & (UDP_HTABLE_SIZE - 1)]) + sk_for_each(sk, node, &udptable[num & (UDP_HTABLE_SIZE - 1)]) if (inet_sk(sk)->num == num) return 1; return 0; } /** - * udp_get_port - common port lookup for IPv4 and IPv6 + * __udp_lib_get_port - UDP/-Lite port lookup for IPv4 and IPv6 * * @sk: socket struct in question * @snum: port number to look up + * @udptable: hash list table, must be of UDP_HTABLE_SIZE + * @port_rover: pointer to record of last unallocated port * @saddr_comp: AF-dependent comparison of bound local IP addresses */ -int udp_get_port(struct sock *sk, unsigned short snum, - int (*saddr_cmp)(const struct sock *sk1, const struct sock *sk2)) +int __udp_lib_get_port(struct sock *sk, unsigned short snum, + struct hlist_head udptable[], int *port_rover, + int (*saddr_comp)(const struct sock *sk1, + const struct sock *sk2 ) ) { struct hlist_node *node; struct hlist_head *head; @@ -150,15 +148,15 @@ int udp_get_port(struct sock *sk, unsigned short snum, 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]; + if (*port_rover > sysctl_local_port_range[1] || + *port_rover < sysctl_local_port_range[0]) + *port_rover = sysctl_local_port_range[0]; best_size_so_far = 32767; - best = result = udp_port_rover; + best = result = *port_rover; for (i = 0; i < UDP_HTABLE_SIZE; i++, result++) { int size; - head = &udp_hash[result & (UDP_HTABLE_SIZE - 1)]; + head = &udptable[result & (UDP_HTABLE_SIZE - 1)]; if (hlist_empty(head)) { if (result > sysctl_local_port_range[1]) result = sysctl_local_port_range[0] + @@ -179,15 +177,15 @@ int udp_get_port(struct sock *sk, unsigned short snum, result = sysctl_local_port_range[0] + ((result - sysctl_local_port_range[0]) & (UDP_HTABLE_SIZE - 1)); - if (!udp_lport_inuse(result)) + if (! __udp_lib_lport_inuse(result, udptable)) break; } if (i >= (1 << 16) / UDP_HTABLE_SIZE) goto fail; gotit: - udp_port_rover = snum = result; + *port_rover = snum = result; } else { - head = &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]; + head = &udptable[snum & (UDP_HTABLE_SIZE - 1)]; sk_for_each(sk2, node, head) if (inet_sk(sk2)->num == snum && @@ -195,12 +193,12 @@ gotit: (!sk2->sk_reuse || !sk->sk_reuse) && (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if || sk2->sk_bound_dev_if == sk->sk_bound_dev_if) && - (*saddr_cmp)(sk, sk2) ) + (*saddr_comp)(sk, sk2) ) goto fail; } inet_sk(sk)->num = snum; if (sk_unhashed(sk)) { - head = &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]; + head = &udptable[snum & (UDP_HTABLE_SIZE - 1)]; sk_add_node(sk, head); sock_prot_inc_use(sk->sk_prot); } @@ -210,7 +208,13 @@ fail: return error; } -static inline int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2) +__inline__ int udp_get_port(struct sock *sk, unsigned short snum, + int (*scmp)(const struct sock *, const struct sock *)) +{ + return __udp_lib_get_port(sk, snum, udp_hash, &udp_port_rover, scmp); +} + +inline int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2) { struct inet_sock *inet1 = inet_sk(sk1), *inet2 = inet_sk(sk2); @@ -224,34 +228,20 @@ static inline int udp_v4_get_port(struct sock *sk, unsigned short snum) return udp_get_port(sk, snum, ipv4_rcv_saddr_equal); } - -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_del_node_init(sk)) { - inet_sk(sk)->num = 0; - sock_prot_dec_use(sk->sk_prot); - } - write_unlock_bh(&udp_hash_lock); -} - /* UDP is nearly always wildcards out the wazoo, it makes no sense to try * harder than this. -DaveM */ -static struct sock *udp_v4_lookup_longway(__be32 saddr, __be16 sport, - __be32 daddr, __be16 dport, int dif) +static struct sock *__udp4_lib_lookup(__be32 saddr, __be16 sport, + __be32 daddr, __be16 dport, + int dif, struct hlist_head udptable[]) { struct sock *sk, *result = NULL; struct hlist_node *node; unsigned short hnum = ntohs(dport); int badness = -1; - sk_for_each(sk, node, &udp_hash[hnum & (UDP_HTABLE_SIZE - 1)]) { + read_lock(&udp_hash_lock); + sk_for_each(sk, node, &udptable[hnum & (UDP_HTABLE_SIZE - 1)]) { struct inet_sock *inet = inet_sk(sk); if (inet->num == hnum && !ipv6_only_sock(sk)) { @@ -285,20 +275,10 @@ static struct sock *udp_v4_lookup_longway(__be32 saddr, __be16 sport, } } } - return result; -} - -static __inline__ struct sock *udp_v4_lookup(__be32 saddr, __be16 sport, - __be32 daddr, __be16 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); + if (result) + sock_hold(result); read_unlock(&udp_hash_lock); - return sk; + return result; } static inline struct sock *udp_v4_mcast_next(struct sock *sk, @@ -340,7 +320,7 @@ found: * to find the appropriate port. */ -void udp_err(struct sk_buff *skb, u32 info) +void __udp4_lib_err(struct sk_buff *skb, u32 info, struct hlist_head udptable[]) { struct inet_sock *inet; struct iphdr *iph = (struct iphdr*)skb->data; @@ -351,7 +331,8 @@ void udp_err(struct sk_buff *skb, u32 info) int harderr; int err; - sk = udp_v4_lookup(iph->daddr, uh->dest, iph->saddr, uh->source, skb->dev->ifindex); + sk = __udp4_lib_lookup(iph->daddr, uh->dest, iph->saddr, uh->source, + skb->dev->ifindex, udptable ); if (sk == NULL) { ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); return; /* No socket for error */ @@ -405,6 +386,11 @@ out: sock_put(sk); } +__inline__ void udp_err(struct sk_buff *skb, u32 info) +{ + return __udp4_lib_err(skb, info, udp_hash); +} + /* * Throw away all pending data and cancel the corking. Socket is locked. */ @@ -419,16 +405,56 @@ static void udp_flush_pending_frames(struct sock *sk) } } +/** + * udp4_hwcsum_outgoing - handle outgoing HW checksumming + * @sk: socket we are sending on + * @skb: sk_buff containing the filled-in UDP header + * (checksum field must be zeroed out) + */ +static void udp4_hwcsum_outgoing(struct sock *sk, struct sk_buff *skb, + __be32 src, __be32 dst, int len ) +{ + unsigned int csum = 0, offset; + struct udphdr *uh = skb->h.uh; + + if (skb_queue_len(&sk->sk_write_queue) == 1) { + /* + * Only one fragment on the socket. + */ + skb->csum = offsetof(struct udphdr, check); + uh->check = ~csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, 0); + } else { + /* + * HW-checksum won't work as there are two or more + * fragments on the socket so that all csums of sk_buffs + * should be together + */ + offset = skb->h.raw - skb->data; + skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); + + skb->ip_summed = CHECKSUM_NONE; + + skb_queue_walk(&sk->sk_write_queue, skb) { + csum = csum_add(csum, skb->csum); + } + + uh->check = csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, csum); + if (uh->check == 0) + uh->check = -1; + } +} + /* * Push out all pending data as one UDP datagram. Socket is locked. */ -static int udp_push_pending_frames(struct sock *sk, struct udp_sock *up) +int udp_push_pending_frames(struct sock *sk, struct udp_sock *up) { struct inet_sock *inet = inet_sk(sk); struct flowi *fl = &inet->cork.fl; struct sk_buff *skb; struct udphdr *uh; int err = 0; + u32 csum = 0; /* Grab the skbuff where UDP header space exists. */ if ((skb = skb_peek(&sk->sk_write_queue)) == NULL) @@ -443,52 +469,28 @@ static int udp_push_pending_frames(struct sock *sk, struct udp_sock *up) uh->len = htons(up->len); uh->check = 0; - if (sk->sk_no_check == UDP_CSUM_NOXMIT) { + if (up->pcflag) /* UDP-Lite */ + csum = udplite_csum_outgoing(sk, skb); + + else if (sk->sk_no_check == UDP_CSUM_NOXMIT) { /* UDP csum disabled */ + skb->ip_summed = CHECKSUM_NONE; goto send; - } - if (skb_queue_len(&sk->sk_write_queue) == 1) { - /* - * Only one fragment on the socket. - */ - if (skb->ip_summed == CHECKSUM_PARTIAL) { - skb->csum = offsetof(struct udphdr, check); - uh->check = ~csum_tcpudp_magic(fl->fl4_src, fl->fl4_dst, - up->len, IPPROTO_UDP, 0); - } else { - skb->csum = csum_partial((char *)uh, - sizeof(struct udphdr), skb->csum); - uh->check = csum_tcpudp_magic(fl->fl4_src, fl->fl4_dst, - up->len, IPPROTO_UDP, skb->csum); - if (uh->check == 0) - uh->check = -1; - } - } else { - unsigned int csum = 0; - /* - * HW-checksum won't work as there are two or more - * fragments on the socket so that all csums of sk_buffs - * should be together. - */ - if (skb->ip_summed == CHECKSUM_PARTIAL) { - int offset = (unsigned char *)uh - skb->data; - skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); + } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */ - skb->ip_summed = CHECKSUM_NONE; - } else { - skb->csum = csum_partial((char *)uh, - sizeof(struct udphdr), skb->csum); - } + udp4_hwcsum_outgoing(sk, skb, fl->fl4_src,fl->fl4_dst, up->len); + goto send; + + } else /* `normal' UDP */ + csum = udp_csum_outgoing(sk, skb); + + /* add protocol-dependent pseudo-header */ + uh->check = csum_tcpudp_magic(fl->fl4_src, fl->fl4_dst, up->len, + sk->sk_protocol, csum ); + if (uh->check == 0) + uh->check = -1; - skb_queue_walk(&sk->sk_write_queue, skb) { - csum = csum_add(csum, skb->csum); - } - uh->check = csum_tcpudp_magic(fl->fl4_src, fl->fl4_dst, - up->len, IPPROTO_UDP, csum); - if (uh->check == 0) - uh->check = -1; - } send: err = ip_push_pending_frames(sk); out: @@ -497,12 +499,6 @@ out: return err; } - -static unsigned short udp_check(struct udphdr *uh, int len, __be32 saddr, __be32 daddr, unsigned long base) -{ - return(csum_tcpudp_magic(saddr, daddr, len, IPPROTO_UDP, base)); -} - int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t len) { @@ -516,8 +512,9 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, __be32 daddr, faddr, saddr; __be16 dport; u8 tos; - int err; + int err, is_udplite = up->pcflag; int corkreq = up->corkflag || msg->msg_flags&MSG_MORE; + int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); if (len > 0xFFFF) return -EMSGSIZE; @@ -622,7 +619,7 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, { .daddr = faddr, .saddr = saddr, .tos = tos } }, - .proto = IPPROTO_UDP, + .proto = sk->sk_protocol, .uli_u = { .ports = { .sport = inet->sport, .dport = dport } } }; @@ -668,8 +665,9 @@ back_from_confirm: do_append_data: up->len += ulen; - err = ip_append_data(sk, ip_generic_getfrag, msg->msg_iov, ulen, - sizeof(struct udphdr), &ipc, rt, + getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; + err = ip_append_data(sk, getfrag, msg->msg_iov, ulen, + sizeof(struct udphdr), &ipc, rt, corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags); if (err) udp_flush_pending_frames(sk); @@ -684,7 +682,7 @@ out: if (free) kfree(ipc.opt); if (!err) { - UDP_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS); + UDP_INC_STATS_USER(UDP_MIB_OUTDATAGRAMS, is_udplite); return len; } /* @@ -695,7 +693,7 @@ out: * seems like overkill. */ if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) { - UDP_INC_STATS_USER(UDP_MIB_SNDBUFERRORS); + UDP_INC_STATS_USER(UDP_MIB_SNDBUFERRORS, is_udplite); } return err; @@ -707,8 +705,8 @@ do_confirm: goto out; } -static int udp_sendpage(struct sock *sk, struct page *page, int offset, - size_t size, int flags) +int udp_sendpage(struct sock *sk, struct page *page, int offset, + size_t size, int flags) { struct udp_sock *up = udp_sk(sk); int ret; @@ -795,29 +793,18 @@ int udp_ioctl(struct sock *sk, int cmd, unsigned long arg) return(0); } -static __inline__ int __udp_checksum_complete(struct sk_buff *skb) -{ - return __skb_checksum_complete(skb); -} - -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. */ -static int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, - size_t len, int noblock, int flags, int *addr_len) +int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, + size_t len, int noblock, int flags, int *addr_len) { struct inet_sock *inet = inet_sk(sk); struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name; struct sk_buff *skb; - int copied, err; + int copied, err, copy_only, is_udplite = IS_UDPLITE(sk); /* * Check any passed addresses @@ -839,15 +826,25 @@ try_again: 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)) + /* + * Decide whether to checksum and/or copy data. + * + * UDP: checksum may have been computed in HW, + * (re-)compute it if message is truncated. + * UDP-Lite: always needs to checksum, no HW support. + */ + copy_only = (skb->ip_summed==CHECKSUM_UNNECESSARY); + + if (is_udplite || (!copy_only && msg->msg_flags&MSG_TRUNC)) { + if (__udp_lib_checksum_complete(skb)) goto csum_copy_err; - err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov, - copied); - } else { + copy_only = 1; + } + + if (copy_only) + 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) @@ -880,7 +877,7 @@ out: return err; csum_copy_err: - UDP_INC_STATS_BH(UDP_MIB_INERRORS); + UDP_INC_STATS_BH(UDP_MIB_INERRORS, is_udplite); skb_kill_datagram(sk, skb, flags); @@ -912,11 +909,6 @@ int udp_disconnect(struct sock *sk, int flags) return 0; } -static void udp_close(struct sock *sk, long timeout) -{ - sk_common_release(sk); -} - /* return: * 1 if the the UDP system should process it * 0 if we should drop this packet @@ -1022,7 +1014,7 @@ static int udp_encap_rcv(struct sock * sk, struct sk_buff *skb) * Note that in the success and error cases, the skb is assumed to * have either been requeued or freed. */ -static int udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb) +int udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb) { struct udp_sock *up = udp_sk(sk); int rc; @@ -1030,10 +1022,8 @@ 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 (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) { - kfree_skb(skb); - return -1; - } + if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) + goto drop; nf_reset(skb); if (up->encap_type) { @@ -1057,31 +1047,68 @@ static int udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb) if (ret < 0) { /* process the ESP packet */ ret = xfrm4_rcv_encap(skb, up->encap_type); - UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS); + UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag); return -ret; } /* FALLTHROUGH -- it's a UDP Packet */ } - if (sk->sk_filter && skb->ip_summed != CHECKSUM_UNNECESSARY) { - if (__udp_checksum_complete(skb)) { - UDP_INC_STATS_BH(UDP_MIB_INERRORS); - kfree_skb(skb); - return -1; + /* + * UDP-Lite specific tests, ignored on UDP sockets + */ + if ((up->pcflag & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) { + + /* + * MIB statistics other than incrementing the error count are + * disabled for the following two types of errors: these depend + * on the application settings, not on the functioning of the + * protocol stack as such. + * + * RFC 3828 here recommends (sec 3.3): "There should also be a + * way ... to ... at least let the receiving application block + * delivery of packets with coverage values less than a value + * provided by the application." + */ + if (up->pcrlen == 0) { /* full coverage was set */ + LIMIT_NETDEBUG(KERN_WARNING "UDPLITE: partial coverage " + "%d while full coverage %d requested\n", + UDP_SKB_CB(skb)->cscov, skb->len); + goto drop; } + /* The next case involves violating the min. coverage requested + * by the receiver. This is subtle: if receiver wants x and x is + * greater than the buffersize/MTU then receiver will complain + * that it wants x while sender emits packets of smaller size y. + * Therefore the above ...()->partial_cov statement is essential. + */ + if (UDP_SKB_CB(skb)->cscov < up->pcrlen) { + LIMIT_NETDEBUG(KERN_WARNING + "UDPLITE: coverage %d too small, need min %d\n", + UDP_SKB_CB(skb)->cscov, up->pcrlen); + goto drop; + } + } + + if (sk->sk_filter && skb->ip_summed != CHECKSUM_UNNECESSARY) { + if (__udp_lib_checksum_complete(skb)) + goto drop; skb->ip_summed = CHECKSUM_UNNECESSARY; } if ((rc = sock_queue_rcv_skb(sk,skb)) < 0) { /* Note that an ENOMEM error is charged twice */ if (rc == -ENOMEM) - UDP_INC_STATS_BH(UDP_MIB_RCVBUFERRORS); - UDP_INC_STATS_BH(UDP_MIB_INERRORS); - kfree_skb(skb); - return -1; + UDP_INC_STATS_BH(UDP_MIB_RCVBUFERRORS, up->pcflag); + goto drop; } - UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS); + + UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag); return 0; + +drop: + UDP_INC_STATS_BH(UDP_MIB_INERRORS, up->pcflag); + kfree_skb(skb); + return -1; } /* @@ -1090,14 +1117,16 @@ static int udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb) * 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, - __be32 saddr, __be32 daddr) +static int __udp4_lib_mcast_deliver(struct sk_buff *skb, + struct udphdr *uh, + __be32 saddr, __be32 daddr, + struct hlist_head udptable[]) { struct sock *sk; int dif; read_lock(&udp_hash_lock); - sk = sk_head(&udp_hash[ntohs(uh->dest) & (UDP_HTABLE_SIZE - 1)]); + sk = sk_head(&udptable[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) { @@ -1131,65 +1160,75 @@ static int udp_v4_mcast_deliver(struct sk_buff *skb, struct udphdr *uh, * Otherwise, csum completion requires chacksumming packet body, * including udp header and folding it to skb->csum. */ -static void udp_checksum_init(struct sk_buff *skb, struct udphdr *uh, - unsigned short ulen, __be32 saddr, __be32 daddr) +static inline void udp4_csum_init(struct sk_buff *skb, struct udphdr *uh) { if (uh->check == 0) { skb->ip_summed = CHECKSUM_UNNECESSARY; } else if (skb->ip_summed == CHECKSUM_COMPLETE) { - if (!udp_check(uh, ulen, saddr, daddr, skb->csum)) + if (!csum_tcpudp_magic(skb->nh.iph->saddr, skb->nh.iph->daddr, + skb->len, IPPROTO_UDP, skb->csum )) skb->ip_summed = CHECKSUM_UNNECESSARY; } if (skb->ip_summed != CHECKSUM_UNNECESSARY) - skb->csum = csum_tcpudp_nofold(saddr, daddr, ulen, IPPROTO_UDP, 0); + skb->csum = csum_tcpudp_nofold(skb->nh.iph->saddr, + skb->nh.iph->daddr, + skb->len, IPPROTO_UDP, 0); /* Probably, we should checksum udp header (it should be in cache * in any case) and data in tiny packets (< rx copybreak). */ + + /* UDP = UDP-Lite with a non-partial checksum coverage */ + UDP_SKB_CB(skb)->partial_cov = 0; } /* * All we need to do is get the socket, and then do a checksum. */ -int udp_rcv(struct sk_buff *skb) +int __udp4_lib_rcv(struct sk_buff *skb, struct hlist_head udptable[], + int is_udplite) { struct sock *sk; - struct udphdr *uh; + struct udphdr *uh = skb->h.uh; unsigned short ulen; struct rtable *rt = (struct rtable*)skb->dst; __be32 saddr = skb->nh.iph->saddr; __be32 daddr = skb->nh.iph->daddr; - int len = skb->len; /* - * Validate the packet and the UDP length. + * Validate the packet. */ if (!pskb_may_pull(skb, sizeof(struct udphdr))) - goto no_header; - - uh = skb->h.uh; + goto drop; /* No space for header. */ ulen = ntohs(uh->len); - - if (ulen > len || ulen < sizeof(*uh)) + if (ulen > skb->len) goto short_packet; - if (pskb_trim_rcsum(skb, ulen)) - goto short_packet; + if(! is_udplite ) { /* UDP validates ulen. */ + + if (ulen < sizeof(*uh) || pskb_trim_rcsum(skb, ulen)) + goto short_packet; - udp_checksum_init(skb, uh, ulen, saddr, daddr); + udp4_csum_init(skb, uh); + + } else { /* UDP-Lite validates cscov. */ + if (udplite4_csum_init(skb, uh)) + goto csum_error; + } if(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST)) - return udp_v4_mcast_deliver(skb, uh, saddr, daddr); + return __udp4_lib_mcast_deliver(skb, uh, saddr, daddr, udptable); - sk = udp_v4_lookup(saddr, uh->source, daddr, uh->dest, skb->dev->ifindex); + sk = __udp4_lib_lookup(saddr, uh->source, daddr, uh->dest, + skb->dev->ifindex, udptable ); if (sk != NULL) { int ret = udp_queue_rcv_skb(sk, skb); sock_put(sk); /* a return value > 0 means to resubmit the input, but - * it it wants the return to be -protocol, or 0 + * it wants the return to be -protocol, or 0 */ if (ret > 0) return -ret; @@ -1201,10 +1240,10 @@ int udp_rcv(struct sk_buff *skb) nf_reset(skb); /* No socket. Drop packet silently, if checksum is wrong */ - if (udp_checksum_complete(skb)) + if (udp_lib_checksum_complete(skb)) goto csum_error; - UDP_INC_STATS_BH(UDP_MIB_NOPORTS); + UDP_INC_STATS_BH(UDP_MIB_NOPORTS, is_udplite); icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); /* @@ -1215,36 +1254,40 @@ int udp_rcv(struct sk_buff *skb) return(0); short_packet: - LIMIT_NETDEBUG(KERN_DEBUG "UDP: short packet: From %u.%u.%u.%u:%u %d/%d to %u.%u.%u.%u:%u\n", + LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: short packet: From %u.%u.%u.%u:%u %d/%d to %u.%u.%u.%u:%u\n", + is_udplite? "-Lite" : "", NIPQUAD(saddr), ntohs(uh->source), ulen, - len, + skb->len, NIPQUAD(daddr), ntohs(uh->dest)); -no_header: - UDP_INC_STATS_BH(UDP_MIB_INERRORS); - kfree_skb(skb); - return(0); + goto drop; csum_error: /* * RFC1122: OK. Discards the bad packet silently (as far as * the network is concerned, anyway) as per 4.1.3.4 (MUST). */ - LIMIT_NETDEBUG(KERN_DEBUG "UDP: bad checksum. From %d.%d.%d.%d:%d to %d.%d.%d.%d:%d ulen %d\n", + LIMIT_NETDEBUG(KERN_DEBUG "UDP%s: bad checksum. From %d.%d.%d.%d:%d to %d.%d.%d.%d:%d ulen %d\n", + is_udplite? "-Lite" : "", NIPQUAD(saddr), ntohs(uh->source), NIPQUAD(daddr), ntohs(uh->dest), ulen); drop: - UDP_INC_STATS_BH(UDP_MIB_INERRORS); + UDP_INC_STATS_BH(UDP_MIB_INERRORS, is_udplite); kfree_skb(skb); return(0); } -static int udp_destroy_sock(struct sock *sk) +__inline__ int udp_rcv(struct sk_buff *skb) +{ + return __udp4_lib_rcv(skb, udp_hash, 0); +} + +int udp_destroy_sock(struct sock *sk) { lock_sock(sk); udp_flush_pending_frames(sk); @@ -1293,6 +1336,32 @@ static int do_udp_setsockopt(struct sock *sk, int level, int optname, } break; + /* + * UDP-Lite's partial checksum coverage (RFC 3828). + */ + /* The sender sets actual checksum coverage length via this option. + * The case coverage > packet length is handled by send module. */ + case UDPLITE_SEND_CSCOV: + if (!up->pcflag) /* Disable the option on UDP sockets */ + return -ENOPROTOOPT; + if (val != 0 && val < 8) /* Illegal coverage: use default (8) */ + val = 8; + up->pcslen = val; + up->pcflag |= UDPLITE_SEND_CC; + break; + + /* The receiver specifies a minimum checksum coverage value. To make + * sense, this should be set to at least 8 (as done below). If zero is + * used, this again means full checksum coverage. */ + case UDPLITE_RECV_CSCOV: + if (!up->pcflag) /* Disable the option on UDP sockets */ + return -ENOPROTOOPT; + if (val != 0 && val < 8) /* Avoid silly minimal values. */ + val = 8; + up->pcrlen = val; + up->pcflag |= UDPLITE_RECV_CC; + break; + default: err = -ENOPROTOOPT; break; @@ -1301,21 +1370,21 @@ static int do_udp_setsockopt(struct sock *sk, int level, int optname, return err; } -static int udp_setsockopt(struct sock *sk, int level, int optname, - char __user *optval, int optlen) +int udp_setsockopt(struct sock *sk, int level, int optname, + char __user *optval, int optlen) { - if (level != SOL_UDP) - return ip_setsockopt(sk, level, optname, optval, optlen); - return do_udp_setsockopt(sk, level, optname, optval, optlen); + if (level == SOL_UDP || level == SOL_UDPLITE) + return do_udp_setsockopt(sk, level, optname, optval, optlen); + return ip_setsockopt(sk, level, optname, optval, optlen); } #ifdef CONFIG_COMPAT -static int compat_udp_setsockopt(struct sock *sk, int level, int optname, - char __user *optval, int optlen) +int compat_udp_setsockopt(struct sock *sk, int level, int optname, + char __user *optval, int optlen) { - if (level != SOL_UDP) - return compat_ip_setsockopt(sk, level, optname, optval, optlen); - return do_udp_setsockopt(sk, level, optname, optval, optlen); + if (level == SOL_UDP || level == SOL_UDPLITE) + return do_udp_setsockopt(sk, level, optname, optval, optlen); + return compat_ip_setsockopt(sk, level, optname, optval, optlen); } #endif @@ -1342,6 +1411,16 @@ static int do_udp_getsockopt(struct sock *sk, int level, int optname, val = up->encap_type; break; + /* The following two cannot be changed on UDP sockets, the return is + * always 0 (which corresponds to the full checksum coverage of UDP). */ + case UDPLITE_SEND_CSCOV: + val = up->pcslen; + break; + + case UDPLITE_RECV_CSCOV: + val = up->pcrlen; + break; + default: return -ENOPROTOOPT; }; @@ -1353,21 +1432,21 @@ static int do_udp_getsockopt(struct sock *sk, int level, int optname, return 0; } -static int udp_getsockopt(struct sock *sk, int level, int optname, - char __user *optval, int __user *optlen) +int udp_getsockopt(struct sock *sk, int level, int optname, + char __user *optval, int __user *optlen) { - if (level != SOL_UDP) - return ip_getsockopt(sk, level, optname, optval, optlen); - return do_udp_getsockopt(sk, level, optname, optval, optlen); + if (level == SOL_UDP || level == SOL_UDPLITE) + return do_udp_getsockopt(sk, level, optname, optval, optlen); + return ip_getsockopt(sk, level, optname, optval, optlen); } #ifdef CONFIG_COMPAT -static int compat_udp_getsockopt(struct sock *sk, int level, int optname, +int compat_udp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { - if (level != SOL_UDP) - return compat_ip_getsockopt(sk, level, optname, optval, optlen); - return do_udp_getsockopt(sk, level, optname, optval, optlen); + if (level == SOL_UDP || level == SOL_UDPLITE) + return do_udp_getsockopt(sk, level, optname, optval, optlen); + return compat_ip_getsockopt(sk, level, optname, optval, optlen); } #endif /** @@ -1387,7 +1466,8 @@ unsigned int udp_poll(struct file *file, struct socket *sock, poll_table *wait) { unsigned int mask = datagram_poll(file, sock, wait); struct sock *sk = sock->sk; - + int is_lite = IS_UDPLITE(sk); + /* Check for false positives due to checksum errors */ if ( (mask & POLLRDNORM) && !(file->f_flags & O_NONBLOCK) && @@ -1397,8 +1477,8 @@ unsigned int udp_poll(struct file *file, struct socket *sock, poll_table *wait) spin_lock_bh(&rcvq->lock); while ((skb = skb_peek(rcvq)) != NULL) { - if (udp_checksum_complete(skb)) { - UDP_INC_STATS_BH(UDP_MIB_INERRORS); + if (udp_lib_checksum_complete(skb)) { + UDP_INC_STATS_BH(UDP_MIB_INERRORS, is_lite); __skb_unlink(skb, rcvq); kfree_skb(skb); } else { @@ -1420,7 +1500,7 @@ unsigned int udp_poll(struct file *file, struct socket *sock, poll_table *wait) struct proto udp_prot = { .name = "UDP", .owner = THIS_MODULE, - .close = udp_close, + .close = udp_lib_close, .connect = ip4_datagram_connect, .disconnect = udp_disconnect, .ioctl = udp_ioctl, @@ -1431,8 +1511,8 @@ struct proto udp_prot = { .recvmsg = udp_recvmsg, .sendpage = udp_sendpage, .backlog_rcv = udp_queue_rcv_skb, - .hash = udp_v4_hash, - .unhash = udp_v4_unhash, + .hash = udp_lib_hash, + .unhash = udp_lib_unhash, .get_port = udp_v4_get_port, .obj_size = sizeof(struct udp_sock), #ifdef CONFIG_COMPAT @@ -1451,7 +1531,7 @@ static struct sock *udp_get_first(struct seq_file *seq) for (state->bucket = 0; state->bucket < UDP_HTABLE_SIZE; ++state->bucket) { struct hlist_node *node; - sk_for_each(sk, node, &udp_hash[state->bucket]) { + sk_for_each(sk, node, state->hashtable + state->bucket) { if (sk->sk_family == state->family) goto found; } @@ -1472,7 +1552,7 @@ try_again: } while (sk && sk->sk_family != state->family); if (!sk && ++state->bucket < UDP_HTABLE_SIZE) { - sk = sk_head(&udp_hash[state->bucket]); + sk = sk_head(state->hashtable + state->bucket); goto try_again; } return sk; @@ -1522,6 +1602,7 @@ static int udp_seq_open(struct inode *inode, struct file *file) if (!s) goto out; s->family = afinfo->family; + s->hashtable = afinfo->hashtable; s->seq_ops.start = udp_seq_start; s->seq_ops.next = udp_seq_next; s->seq_ops.show = afinfo->seq_show; @@ -1588,7 +1669,7 @@ static void udp4_format_sock(struct sock *sp, char *tmpbuf, int bucket) atomic_read(&sp->sk_refcnt), sp); } -static int udp4_seq_show(struct seq_file *seq, void *v) +int udp4_seq_show(struct seq_file *seq, void *v) { if (v == SEQ_START_TOKEN) seq_printf(seq, "%-127s\n", @@ -1611,6 +1692,7 @@ static struct udp_seq_afinfo udp4_seq_afinfo = { .owner = THIS_MODULE, .name = "udp", .family = AF_INET, + .hashtable = udp_hash, .seq_show = udp4_seq_show, .seq_fops = &udp4_seq_fops, }; -- cgit v1.2.3-70-g09d2