From aa6615814533c634190019ee3a5b10490026d545 Mon Sep 17 00:00:00 2001 From: Francesco Fusco Date: Tue, 24 Sep 2013 15:43:09 +0200 Subject: [PATCH] ipv4: processing ancillary IP_TOS or IP_TTL If IP_TOS or IP_TTL are specified as ancillary data, then sendmsg() sends out packets with the specified TTL or TOS overriding the socket values specified with the traditional setsockopt(). The struct inet_cork stores the values of TOS, TTL and priority that are passed through the struct ipcm_cookie. If there are user-specified TOS (tos != -1) or TTL (ttl != 0) in the struct ipcm_cookie, these values are used to override the per-socket values. In case of TOS also the priority is changed accordingly. Two helper functions get_rttos and get_rtconn_flags are defined to take into account the presence of a user specified TOS value when computing RT_TOS and RT_CONN_FLAGS. Signed-off-by: Francesco Fusco Signed-off-by: David S. Miller --- include/net/inet_sock.h | 3 +++ include/net/ip.h | 11 +++++++++++ include/net/route.h | 1 + net/ipv4/icmp.c | 5 +++++ net/ipv4/ip_output.c | 13 ++++++++++--- net/ipv4/ping.c | 4 +++- net/ipv4/raw.c | 4 +++- net/ipv4/udp.c | 4 +++- 8 files changed, 39 insertions(+), 6 deletions(-) diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index 636d203..f314177 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h @@ -103,6 +103,9 @@ struct inet_cork { int length; /* Total length of all frames */ struct dst_entry *dst; u8 tx_flags; + __u8 ttl; + __s16 tos; + char priority; }; struct inet_cork_full { diff --git a/include/net/ip.h b/include/net/ip.h index 0135f38..77b4f9b 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -28,6 +28,7 @@ #include #include +#include #include #include @@ -140,6 +141,16 @@ static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4) return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base); } +static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet) +{ + return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos); +} + +static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk) +{ + return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk); +} + /* datagram.c */ int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); diff --git a/include/net/route.h b/include/net/route.h index 6f572ca6..0ad8e01 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -39,6 +39,7 @@ #define RTO_ONLINK 0x01 #define RT_CONN_FLAGS(sk) (RT_TOS(inet_sk(sk)->tos) | sock_flag(sk, SOCK_LOCALROUTE)) +#define RT_CONN_FLAGS_TOS(sk,tos) (RT_TOS(tos) | sock_flag(sk, SOCK_LOCALROUTE)) struct fib_nh; struct fib_info; diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index 5f7d11a..5c0e8bc6 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -353,6 +353,9 @@ static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb) saddr = fib_compute_spec_dst(skb); ipc.opt = NULL; ipc.tx_flags = 0; + ipc.ttl = 0; + ipc.tos = -1; + if (icmp_param->replyopts.opt.opt.optlen) { ipc.opt = &icmp_param->replyopts.opt; if (ipc.opt->opt.srr) @@ -608,6 +611,8 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info) ipc.addr = iph->saddr; ipc.opt = &icmp_param->replyopts.opt; ipc.tx_flags = 0; + ipc.ttl = 0; + ipc.tos = -1; rt = icmp_route_lookup(net, &fl4, skb_in, iph, saddr, tos, type, code, icmp_param); diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index a04d872..7d8357b 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -1060,6 +1060,9 @@ static int ip_setup_cork(struct sock *sk, struct inet_cork *cork, rt->dst.dev->mtu : dst_mtu(&rt->dst); cork->dst = &rt->dst; cork->length = 0; + cork->ttl = ipc->ttl; + cork->tos = ipc->tos; + cork->priority = ipc->priority; cork->tx_flags = ipc->tx_flags; return 0; @@ -1311,7 +1314,9 @@ struct sk_buff *__ip_make_skb(struct sock *sk, if (cork->flags & IPCORK_OPT) opt = cork->opt; - if (rt->rt_type == RTN_MULTICAST) + if (cork->ttl != 0) + ttl = cork->ttl; + else if (rt->rt_type == RTN_MULTICAST) ttl = inet->mc_ttl; else ttl = ip_select_ttl(inet, &rt->dst); @@ -1319,7 +1324,7 @@ struct sk_buff *__ip_make_skb(struct sock *sk, iph = ip_hdr(skb); iph->version = 4; iph->ihl = 5; - iph->tos = inet->tos; + iph->tos = (cork->tos != -1) ? cork->tos : inet->tos; iph->frag_off = df; iph->ttl = ttl; iph->protocol = sk->sk_protocol; @@ -1331,7 +1336,7 @@ struct sk_buff *__ip_make_skb(struct sock *sk, ip_options_build(skb, opt, cork->addr, rt, 0); } - skb->priority = sk->sk_priority; + skb->priority = (cork->tos != -1) ? cork->priority: sk->sk_priority; skb->mark = sk->sk_mark; /* * Steal rt from cork.dst to avoid a pair of atomic_inc/atomic_dec @@ -1481,6 +1486,8 @@ void ip_send_unicast_reply(struct net *net, struct sk_buff *skb, __be32 daddr, ipc.addr = daddr; ipc.opt = NULL; ipc.tx_flags = 0; + ipc.ttl = 0; + ipc.tos = -1; if (replyopts.opt.opt.optlen) { ipc.opt = &replyopts.opt; diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c index d7d9882..706d108e 100644 --- a/net/ipv4/ping.c +++ b/net/ipv4/ping.c @@ -713,6 +713,8 @@ int ping_v4_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, ipc.opt = NULL; ipc.oif = sk->sk_bound_dev_if; ipc.tx_flags = 0; + ipc.ttl = 0; + ipc.tos = -1; sock_tx_timestamp(sk, &ipc.tx_flags); @@ -744,7 +746,7 @@ int ping_v4_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, return -EINVAL; faddr = ipc.opt->opt.faddr; } - tos = RT_TOS(inet->tos); + tos = get_rttos(&ipc, inet); if (sock_flag(sk, SOCK_LOCALROUTE) || (msg->msg_flags & MSG_DONTROUTE) || (ipc.opt && ipc.opt->opt.is_strictroute)) { diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index bfec521..a3fe534 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -517,6 +517,8 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, ipc.addr = inet->inet_saddr; ipc.opt = NULL; ipc.tx_flags = 0; + ipc.ttl = 0; + ipc.tos = -1; ipc.oif = sk->sk_bound_dev_if; if (msg->msg_controllen) { @@ -556,7 +558,7 @@ static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, daddr = ipc.opt->opt.faddr; } } - tos = RT_CONN_FLAGS(sk); + tos = get_rtconn_flags(&ipc, sk); if (msg->msg_flags & MSG_DONTROUTE) tos |= RTO_ONLINK; diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 74d2c95..22462d94 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -855,6 +855,8 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, ipc.opt = NULL; ipc.tx_flags = 0; + ipc.ttl = 0; + ipc.tos = -1; getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag; @@ -938,7 +940,7 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, faddr = ipc.opt->opt.faddr; connected = 0; } - tos = RT_TOS(inet->tos); + tos = get_rttos(&ipc, inet); if (sock_flag(sk, SOCK_LOCALROUTE) || (msg->msg_flags & MSG_DONTROUTE) || (ipc.opt && ipc.opt->opt.is_strictroute)) { -- 2.7.4