From 493ced1ac47c48bb86d9d4e8e87df8592be85a0e Mon Sep 17 00:00:00 2001 From: David Ahern Date: Sat, 8 Jun 2019 14:53:32 -0700 Subject: [PATCH] ipv4: Allow routes to use nexthop objects Add support for RTA_NH_ID attribute to allow a user to specify a nexthop id to use with a route. fc_nh_id is added to fib_config to hold the value passed in the RTA_NH_ID attribute. If a nexthop id is given, the gateway, device, encap and multipath attributes can not be set. Update fib_nh_match to check ids on a route delete. Signed-off-by: David Ahern Signed-off-by: David S. Miller --- include/net/ip_fib.h | 1 + net/ipv4/fib_frontend.c | 19 +++++++++++++++++++ net/ipv4/fib_semantics.c | 15 +++++++++++++++ 3 files changed, 35 insertions(+) diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index 4cdf8bc22efd..7e1e621a56df 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -40,6 +40,7 @@ struct fib_config { u32 fc_flags; u32 fc_priority; __be32 fc_prefsrc; + u32 fc_nh_id; struct nlattr *fc_mx; struct rtnexthop *fc_mp; int fc_mx_len; diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 33b0dbe84aa6..108191667531 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -671,6 +671,7 @@ const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = { [RTA_IP_PROTO] = { .type = NLA_U8 }, [RTA_SPORT] = { .type = NLA_U16 }, [RTA_DPORT] = { .type = NLA_U16 }, + [RTA_NH_ID] = { .type = NLA_U32 }, }; int fib_gw_from_via(struct fib_config *cfg, struct nlattr *nla, @@ -808,6 +809,18 @@ static int rtm_to_fib_config(struct net *net, struct sk_buff *skb, if (err < 0) goto errout; break; + case RTA_NH_ID: + cfg->fc_nh_id = nla_get_u32(attr); + break; + } + } + + if (cfg->fc_nh_id) { + if (cfg->fc_oif || cfg->fc_gw_family || + cfg->fc_encap || cfg->fc_mp) { + NL_SET_ERR_MSG(extack, + "Nexthop specification and nexthop id are mutually exclusive"); + return -EINVAL; } } @@ -834,6 +847,12 @@ static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, if (err < 0) goto errout; + if (cfg.fc_nh_id && !nexthop_find_by_id(net, cfg.fc_nh_id)) { + NL_SET_ERR_MSG(extack, "Nexthop id does not exist"); + err = -EINVAL; + goto errout; + } + tb = fib_get_table(net, cfg.fc_table); if (!tb) { NL_SET_ERR_MSG(extack, "FIB table does not exist"); diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index afa4af1f9326..2c24d8e3b126 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -789,6 +789,12 @@ int fib_nh_match(struct fib_config *cfg, struct fib_info *fi, if (cfg->fc_priority && cfg->fc_priority != fi->fib_priority) return 1; + if (cfg->fc_nh_id) { + if (fi->nh && cfg->fc_nh_id == fi->nh->id) + return 0; + return 1; + } + if (cfg->fc_oif || cfg->fc_gw_family) { struct fib_nh *nh = fib_info_nh(fi, 0); @@ -1302,6 +1308,15 @@ struct fib_info *fib_create_info(struct fib_config *cfg, goto err_inval; } + if (cfg->fc_nh_id) { + nh = nexthop_find_by_id(net, cfg->fc_nh_id); + if (!nh) { + NL_SET_ERR_MSG(extack, "Nexthop id does not exist"); + goto err_inval; + } + nhs = 0; + } + #ifdef CONFIG_IP_ROUTE_MULTIPATH if (cfg->fc_mp) { nhs = fib_count_nexthops(cfg->fc_mp, cfg->fc_mp_len, extack); -- 2.30.2