From ec20b283009346adc66d5a460b1f8fb5adafbcfe Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Fri, 5 Apr 2024 22:05:00 +0200 Subject: ipv4: Set scope explicitly in ip_route_output(). Add a "scope" parameter to ip_route_output() so that callers don't have to override the tos parameter with the RTO_ONLINK flag if they want a local scope. This will allow converting flowi4_tos to dscp_t in the future, thus allowing static analysers to flag invalid interactions between "tos" (the DSCP bits) and ECN. Only three users ask for local scope (bonding, arp and atm). The others continue to use RT_SCOPE_UNIVERSE. While there, add a comment to warn users about the limitations of ip_route_output(). Signed-off-by: Guillaume Nault Acked-by: Leon Romanovsky # infiniband Signed-off-by: David S. Miller --- include/net/route.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'include/net/route.h') diff --git a/include/net/route.h b/include/net/route.h index d4a0147942f1..315a8acee6c6 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -141,15 +141,22 @@ static inline struct rtable *ip_route_output_key(struct net *net, struct flowi4 return ip_route_output_flow(net, flp, NULL); } +/* Simplistic IPv4 route lookup function. + * This is only suitable for some particular use cases: since the flowi4 + * structure is only partially set, it may bypass some fib-rules. + */ static inline struct rtable *ip_route_output(struct net *net, __be32 daddr, - __be32 saddr, u8 tos, int oif) + __be32 saddr, u8 tos, int oif, + __u8 scope) { struct flowi4 fl4 = { .flowi4_oif = oif, .flowi4_tos = tos, + .flowi4_scope = scope, .daddr = daddr, .saddr = saddr, }; + return ip_route_output_key(net, &fl4); } -- cgit v1.2.3 From 5618603f5d063c8d769d2e64cd440f787567fd13 Mon Sep 17 00:00:00 2001 From: Guillaume Nault Date: Wed, 10 Apr 2024 15:14:29 +0200 Subject: ipv4: Remove RTO_ONLINK. RTO_ONLINK was a flag used in ->flowi4_tos that allowed to alter the scope of an IPv4 route lookup. Setting this flag was equivalent to specifying RT_SCOPE_LINK in ->flowi4_scope. With commit ec20b2830093 ("ipv4: Set scope explicitly in ip_route_output()."), the last users of RTO_ONLINK have been removed. Therefore, we can now drop the code that checked this bit and stop modifying ->flowi4_scope in ip_route_output_key_hash(). Signed-off-by: Guillaume Nault Reviewed-by: Przemek Kitszel Reviewed-by: David Ahern Link: https://lore.kernel.org/r/57de760565cab55df7b129f523530ac6475865b2.1712754146.git.gnault@redhat.com Signed-off-by: Jakub Kicinski --- include/net/route.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'include/net/route.h') diff --git a/include/net/route.h b/include/net/route.h index 315a8acee6c6..630d1ef6868a 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -35,8 +35,6 @@ #include #include -#define RTO_ONLINK 0x01 - static inline __u8 ip_sock_rt_scope(const struct sock *sk) { if (sock_flag(sk, SOCK_LOCALROUTE)) -- cgit v1.2.3 From 05d6d492097c55f2d153fc3fd33cbe78e1e28e0a Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 29 Apr 2024 13:30:09 +0000 Subject: inet: introduce dst_rtable() helper I added dst_rt6_info() in commit e8dfd42c17fa ("ipv6: introduce dst_rt6_info() helper") This patch does a similar change for IPv4. Instead of (struct rtable *)dst casts, we can use : #define dst_rtable(_ptr) \ container_of_const(_ptr, struct rtable, dst) Patch is smaller than IPv6 one, because IPv4 has skb_rtable() helper. Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Reviewed-by: Sabrina Dubroca Link: https://lore.kernel.org/r/20240429133009.1227754-1-edumazet@google.com Signed-off-by: Jakub Kicinski --- include/net/route.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'include/net/route.h') diff --git a/include/net/route.h b/include/net/route.h index 630d1ef6868a..93833cfe9c96 100644 --- a/include/net/route.h +++ b/include/net/route.h @@ -75,6 +75,17 @@ struct rtable { rt_pmtu:31; }; +#define dst_rtable(_ptr) container_of_const(_ptr, struct rtable, dst) + +/** + * skb_rtable - Returns the skb &rtable + * @skb: buffer + */ +static inline struct rtable *skb_rtable(const struct sk_buff *skb) +{ + return dst_rtable(skb_dst(skb)); +} + static inline bool rt_is_input_route(const struct rtable *rt) { return rt->rt_is_input != 0; -- cgit v1.2.3