From 726de790f66029a7654b3e748f8d3e7888a30ae5 Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Mon, 22 May 2023 16:37:57 +0200 Subject: [PATCH 1/3] ping: Stop using RTO_ONLINK. Define a new helper to figure out the correct route scope to use on TX, depending on socket configuration, ancillary data and send flags. Use this new helper to properly initialise the scope in flowi4_init_output(), instead of overriding tos with the RTO_ONLINK flag. The objective is to eventually remove RTO_ONLINK, which will allow converting .flowi4_tos to dscp_t. Signed-off-by: Guillaume Nault Reviewed-by: David Ahern Signed-off-by: David S. Miller --- include/net/ip.h | 13 +++++++++++++ net/ipv4/ping.c | 15 +++++---------- 2 files changed, 18 insertions(+), 10 deletions(-) diff --git a/include/net/ip.h b/include/net/ip.h index 7627a4df893be..f1cb28d649e4b 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -240,6 +240,19 @@ 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); } +/* Get the route scope that should be used when sending a packet. */ +static inline u8 ip_sendmsg_scope(const struct inet_sock *inet, + const struct ipcm_cookie *ipc, + const struct msghdr *msg) +{ + if (sock_flag(&inet->sk, SOCK_LOCALROUTE) || + msg->msg_flags & MSG_DONTROUTE || + (ipc->opt && ipc->opt->opt.is_strictroute)) + return RT_SCOPE_LINK; + + return RT_SCOPE_UNIVERSE; +} + 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); diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c index 3793c81bda8a6..25dd78cee1792 100644 --- a/net/ipv4/ping.c +++ b/net/ipv4/ping.c @@ -705,7 +705,7 @@ static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) struct ip_options_data opt_copy; int free = 0; __be32 saddr, daddr, faddr; - u8 tos; + u8 tos, scope; int err; pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num); @@ -769,11 +769,7 @@ static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) faddr = ipc.opt->opt.faddr; } tos = get_rttos(&ipc, inet); - if (sock_flag(sk, SOCK_LOCALROUTE) || - (msg->msg_flags & MSG_DONTROUTE) || - (ipc.opt && ipc.opt->opt.is_strictroute)) { - tos |= RTO_ONLINK; - } + scope = ip_sendmsg_scope(inet, &ipc, msg); if (ipv4_is_multicast(daddr)) { if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif)) @@ -783,10 +779,9 @@ static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) } else if (!ipc.oif) ipc.oif = inet->uc_index; - flowi4_init_output(&fl4, ipc.oif, ipc.sockc.mark, tos, - RT_SCOPE_UNIVERSE, sk->sk_protocol, - inet_sk_flowi_flags(sk), faddr, saddr, 0, 0, - sk->sk_uid); + flowi4_init_output(&fl4, ipc.oif, ipc.sockc.mark, tos, scope, + sk->sk_protocol, inet_sk_flowi_flags(sk), faddr, + saddr, 0, 0, sk->sk_uid); fl4.fl4_icmp_type = user_icmph.type; fl4.fl4_icmp_code = user_icmph.code; From c85be08fc4fa44f07167be0377ebaa8d36b1dd58 Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Mon, 22 May 2023 16:38:02 +0200 Subject: [PATCH 2/3] raw: Stop using RTO_ONLINK. Use ip_sendmsg_scope() to properly initialise the scope in flowi4_init_output(), instead of overriding tos with the RTO_ONLINK flag. The objective is to eventually remove RTO_ONLINK, which will allow converting .flowi4_tos to dscp_t. The MSG_DONTROUTE and SOCK_LOCALROUTE cases were already handled by raw_sendmsg() (SOCK_LOCALROUTE was handled by the RT_CONN_FLAGS*() macros called by get_rtconn_flags()). However, opt.is_strictroute wasn't taken into account. Therefore, a side effect of this patch is to now honour opt.is_strictroute, and thus align raw_sendmsg() with ping_v4_sendmsg() and udp_sendmsg(). Since raw_sendmsg() was the only user of get_rtconn_flags(), we can now remove this function. Signed-off-by: Guillaume Nault Reviewed-by: David Ahern Signed-off-by: David S. Miller --- include/net/ip.h | 5 ----- net/ipv4/raw.c | 10 ++++------ 2 files changed, 4 insertions(+), 11 deletions(-) diff --git a/include/net/ip.h b/include/net/ip.h index f1cb28d649e4b..8a3860a916dc3 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -258,11 +258,6 @@ 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); int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index ff712bf2a98d1..8b7b5c842bdd5 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -476,10 +476,10 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) struct ipcm_cookie ipc; struct rtable *rt = NULL; struct flowi4 fl4; + u8 tos, scope; int free = 0; __be32 daddr; __be32 saddr; - u8 tos; int err; struct ip_options_data opt_copy; struct raw_frag_vec rfv; @@ -572,9 +572,8 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) daddr = ipc.opt->opt.faddr; } } - tos = get_rtconn_flags(&ipc, sk); - if (msg->msg_flags & MSG_DONTROUTE) - tos |= RTO_ONLINK; + tos = get_rttos(&ipc, inet); + scope = ip_sendmsg_scope(inet, &ipc, msg); if (ipv4_is_multicast(daddr)) { if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif)) @@ -597,8 +596,7 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) } } - flowi4_init_output(&fl4, ipc.oif, ipc.sockc.mark, tos, - RT_SCOPE_UNIVERSE, + flowi4_init_output(&fl4, ipc.oif, ipc.sockc.mark, tos, scope, hdrincl ? IPPROTO_RAW : sk->sk_protocol, inet_sk_flowi_flags(sk) | (hdrincl ? FLOWI_FLAG_KNOWN_NH : 0), From 0e26371db548834052a8f0c3e138c5ff07e253a0 Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Mon, 22 May 2023 16:38:07 +0200 Subject: [PATCH 3/3] udp: Stop using RTO_ONLINK. Use ip_sendmsg_scope() to properly initialise the scope in flowi4_init_output(), instead of overriding tos with the RTO_ONLINK flag. The objective is to eventually remove RTO_ONLINK, which will allow converting .flowi4_tos to dscp_t. Now that the scope is determined by ip_sendmsg_scope(), we need to check its result to set the 'connected' variable. Signed-off-by: Guillaume Nault Reviewed-by: David Ahern Signed-off-by: David S. Miller --- net/ipv4/udp.c | 17 ++++++----------- 1 file changed, 6 insertions(+), 11 deletions(-) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 2879dc6d66ea5..e992dd5392e36 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1062,8 +1062,8 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) int free = 0; int connected = 0; __be32 daddr, faddr, saddr; + u8 tos, scope; __be16 dport; - u8 tos; int err, is_udplite = IS_UDPLITE(sk); int corkreq = READ_ONCE(up->corkflag) || msg->msg_flags&MSG_MORE; int (*getfrag)(void *, char *, int, int, int, struct sk_buff *); @@ -1183,12 +1183,9 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) connected = 0; } tos = get_rttos(&ipc, inet); - if (sock_flag(sk, SOCK_LOCALROUTE) || - (msg->msg_flags & MSG_DONTROUTE) || - (ipc.opt && ipc.opt->opt.is_strictroute)) { - tos |= RTO_ONLINK; + scope = ip_sendmsg_scope(inet, &ipc, msg); + if (scope == RT_SCOPE_LINK) connected = 0; - } if (ipv4_is_multicast(daddr)) { if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif)) @@ -1221,11 +1218,9 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) fl4 = &fl4_stack; - flowi4_init_output(fl4, ipc.oif, ipc.sockc.mark, tos, - RT_SCOPE_UNIVERSE, sk->sk_protocol, - flow_flags, - faddr, saddr, dport, inet->inet_sport, - sk->sk_uid); + flowi4_init_output(fl4, ipc.oif, ipc.sockc.mark, tos, scope, + sk->sk_protocol, flow_flags, faddr, saddr, + dport, inet->inet_sport, sk->sk_uid); security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4)); rt = ip_route_output_flow(net, fl4, sk);