From 074350e2ebcab9cf62528984a617cc0a05b24fff Mon Sep 17 00:00:00 2001 From: David Ahern Date: Sat, 27 May 2017 16:19:31 -0600 Subject: net: mpls: Add extack messages for route add and delete failures Add error messages for failures in adding and deleting mpls routes. This covers most of the annoying EINVAL errors. Signed-off-by: David Ahern Signed-off-by: David S. Miller --- net/mpls/af_mpls.c | 125 ++++++++++++++++++++++++++++++++++++---------------- net/mpls/internal.h | 2 +- 2 files changed, 87 insertions(+), 40 deletions(-) (limited to 'net/mpls') diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c index 726eafecc793..0133d1ad9032 100644 --- a/net/mpls/af_mpls.c +++ b/net/mpls/af_mpls.c @@ -720,7 +720,8 @@ errout: static int mpls_nh_build(struct net *net, struct mpls_route *rt, struct mpls_nh *nh, int oif, struct nlattr *via, - struct nlattr *newdst, u8 max_labels) + struct nlattr *newdst, u8 max_labels, + struct netlink_ext_ack *extack) { int err = -ENOMEM; @@ -729,14 +730,14 @@ static int mpls_nh_build(struct net *net, struct mpls_route *rt, if (newdst) { err = nla_get_labels(newdst, max_labels, &nh->nh_labels, - nh->nh_label, NULL); + nh->nh_label, extack); if (err) goto errout; } if (via) { err = nla_get_via(via, &nh->nh_via_alen, &nh->nh_via_table, - __mpls_nh_via(rt, nh)); + __mpls_nh_via(rt, nh), extack); if (err) goto errout; } else { @@ -803,7 +804,8 @@ static u8 mpls_count_nexthops(struct rtnexthop *rtnh, int len, } static int mpls_nh_build_multi(struct mpls_route_config *cfg, - struct mpls_route *rt, u8 max_labels) + struct mpls_route *rt, u8 max_labels, + struct netlink_ext_ack *extack) { struct rtnexthop *rtnh = cfg->rc_mp; struct nlattr *nla_via, *nla_newdst; @@ -837,7 +839,7 @@ static int mpls_nh_build_multi(struct mpls_route_config *cfg, err = mpls_nh_build(cfg->rc_nlinfo.nl_net, rt, nh, rtnh->rtnh_ifindex, nla_via, nla_newdst, - max_labels); + max_labels, extack); if (err) goto errout; @@ -856,20 +858,28 @@ errout: return err; } -static bool mpls_label_ok(struct net *net, unsigned int index) +static bool mpls_label_ok(struct net *net, unsigned int index, + struct netlink_ext_ack *extack) { /* Reserved labels may not be set */ - if (index < MPLS_LABEL_FIRST_UNRESERVED) + if (index < MPLS_LABEL_FIRST_UNRESERVED) { + NL_SET_ERR_MSG(extack, + "Invalid label - must be MPLS_LABEL_FIRST_UNRESERVED or higher"); return false; + } /* The full 20 bit range may not be supported. */ - if (index >= net->mpls.platform_labels) + if (index >= net->mpls.platform_labels) { + NL_SET_ERR_MSG(extack, + "Label >= configured maximum in platform_labels"); return false; + } return true; } -static int mpls_route_add(struct mpls_route_config *cfg) +static int mpls_route_add(struct mpls_route_config *cfg, + struct netlink_ext_ack *extack) { struct mpls_route __rcu **platform_label; struct net *net = cfg->rc_nlinfo.nl_net; @@ -888,13 +898,15 @@ static int mpls_route_add(struct mpls_route_config *cfg) index = find_free_label(net); } - if (!mpls_label_ok(net, index)) + if (!mpls_label_ok(net, index, extack)) goto errout; /* Append makes no sense with mpls */ err = -EOPNOTSUPP; - if (cfg->rc_nlflags & NLM_F_APPEND) + if (cfg->rc_nlflags & NLM_F_APPEND) { + NL_SET_ERR_MSG(extack, "MPLS does not support route append"); goto errout; + } err = -EEXIST; platform_label = rtnl_dereference(net->mpls.platform_label); @@ -921,8 +933,10 @@ static int mpls_route_add(struct mpls_route_config *cfg) nhs = 1; } - if (nhs == 0) + if (nhs == 0) { + NL_SET_ERR_MSG(extack, "Route does not contain a nexthop"); goto errout; + } err = -ENOMEM; rt = mpls_rt_alloc(nhs, max_via_alen, max_labels); @@ -936,7 +950,7 @@ static int mpls_route_add(struct mpls_route_config *cfg) rt->rt_ttl_propagate = cfg->rc_ttl_propagate; if (cfg->rc_mp) - err = mpls_nh_build_multi(cfg, rt, max_labels); + err = mpls_nh_build_multi(cfg, rt, max_labels, extack); else err = mpls_nh_build_from_cfg(cfg, rt); if (err) @@ -952,7 +966,8 @@ errout: return err; } -static int mpls_route_del(struct mpls_route_config *cfg) +static int mpls_route_del(struct mpls_route_config *cfg, + struct netlink_ext_ack *extack) { struct net *net = cfg->rc_nlinfo.nl_net; unsigned index; @@ -960,7 +975,7 @@ static int mpls_route_del(struct mpls_route_config *cfg) index = cfg->rc_label; - if (!mpls_label_ok(net, index)) + if (!mpls_label_ok(net, index, extack)) goto errout; mpls_route_update(net, index, NULL, &cfg->rc_nlinfo); @@ -1626,19 +1641,25 @@ out: } EXPORT_SYMBOL_GPL(nla_get_labels); -int nla_get_via(const struct nlattr *nla, u8 *via_alen, - u8 *via_table, u8 via_addr[]) +int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table, + u8 via_addr[], struct netlink_ext_ack *extack) { struct rtvia *via = nla_data(nla); int err = -EINVAL; int alen; - if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) + if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) { + NL_SET_ERR_MSG_ATTR(extack, nla, + "Invalid attribute length for RTA_VIA"); goto errout; + } alen = nla_len(nla) - offsetof(struct rtvia, rtvia_addr); - if (alen > MAX_VIA_ALEN) + if (alen > MAX_VIA_ALEN) { + NL_SET_ERR_MSG_ATTR(extack, nla, + "Invalid address length for RTA_VIA"); goto errout; + } /* Validate the address family */ switch (via->rtvia_family) { @@ -1668,8 +1689,10 @@ errout: return err; } -static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh, - struct mpls_route_config *cfg) +static int rtm_to_route_config(struct sk_buff *skb, + struct nlmsghdr *nlh, + struct mpls_route_config *cfg, + struct netlink_ext_ack *extack) { struct rtmsg *rtm; struct nlattr *tb[RTA_MAX+1]; @@ -1677,35 +1700,54 @@ static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh, int err; err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_mpls_policy, - NULL); + extack); if (err < 0) goto errout; err = -EINVAL; rtm = nlmsg_data(nlh); - if (rtm->rtm_family != AF_MPLS) + if (rtm->rtm_family != AF_MPLS) { + NL_SET_ERR_MSG(extack, "Invalid address family in rtmsg"); goto errout; - if (rtm->rtm_dst_len != 20) + } + if (rtm->rtm_dst_len != 20) { + NL_SET_ERR_MSG(extack, "rtm_dst_len must be 20 for MPLS"); goto errout; - if (rtm->rtm_src_len != 0) + } + if (rtm->rtm_src_len != 0) { + NL_SET_ERR_MSG(extack, "rtm_src_len must be 0 for MPLS"); goto errout; - if (rtm->rtm_tos != 0) + } + if (rtm->rtm_tos != 0) { + NL_SET_ERR_MSG(extack, "rtm_tos must be 0 for MPLS"); goto errout; - if (rtm->rtm_table != RT_TABLE_MAIN) + } + if (rtm->rtm_table != RT_TABLE_MAIN) { + NL_SET_ERR_MSG(extack, + "MPLS only supports the main route table"); goto errout; + } /* Any value is acceptable for rtm_protocol */ /* As mpls uses destination specific addresses * (or source specific address in the case of multicast) * all addresses have universal scope. */ - if (rtm->rtm_scope != RT_SCOPE_UNIVERSE) + if (rtm->rtm_scope != RT_SCOPE_UNIVERSE) { + NL_SET_ERR_MSG(extack, + "Invalid route scope - MPLS only supports UNIVERSE"); goto errout; - if (rtm->rtm_type != RTN_UNICAST) + } + if (rtm->rtm_type != RTN_UNICAST) { + NL_SET_ERR_MSG(extack, + "Invalid route type - MPLS only supports UNICAST"); goto errout; - if (rtm->rtm_flags != 0) + } + if (rtm->rtm_flags != 0) { + NL_SET_ERR_MSG(extack, "rtm_flags must be 0 for MPLS"); goto errout; + } cfg->rc_label = LABEL_NOT_SPECIFIED; cfg->rc_protocol = rtm->rtm_protocol; @@ -1728,25 +1770,26 @@ static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh, case RTA_NEWDST: if (nla_get_labels(nla, MAX_NEW_LABELS, &cfg->rc_output_labels, - cfg->rc_output_label, NULL)) + cfg->rc_output_label, extack)) goto errout; break; case RTA_DST: { u8 label_count; if (nla_get_labels(nla, 1, &label_count, - &cfg->rc_label, NULL)) + &cfg->rc_label, extack)) goto errout; if (!mpls_label_ok(cfg->rc_nlinfo.nl_net, - cfg->rc_label)) + cfg->rc_label, extack)) goto errout; break; } case RTA_VIA: { if (nla_get_via(nla, &cfg->rc_via_alen, - &cfg->rc_via_table, cfg->rc_via)) + &cfg->rc_via_table, cfg->rc_via, + extack)) goto errout; break; } @@ -1760,14 +1803,18 @@ static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh, { u8 ttl_propagate = nla_get_u8(nla); - if (ttl_propagate > 1) + if (ttl_propagate > 1) { + NL_SET_ERR_MSG_ATTR(extack, nla, + "RTA_TTL_PROPAGATE can only be 0 or 1"); goto errout; + } cfg->rc_ttl_propagate = ttl_propagate ? MPLS_TTL_PROP_ENABLED : MPLS_TTL_PROP_DISABLED; break; } default: + NL_SET_ERR_MSG_ATTR(extack, nla, "Unknown attribute"); /* Unsupported attribute */ goto errout; } @@ -1788,11 +1835,11 @@ static int mpls_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh, if (!cfg) return -ENOMEM; - err = rtm_to_route_config(skb, nlh, cfg); + err = rtm_to_route_config(skb, nlh, cfg, extack); if (err < 0) goto out; - err = mpls_route_del(cfg); + err = mpls_route_del(cfg, extack); out: kfree(cfg); @@ -1810,11 +1857,11 @@ static int mpls_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh, if (!cfg) return -ENOMEM; - err = rtm_to_route_config(skb, nlh, cfg); + err = rtm_to_route_config(skb, nlh, cfg, extack); if (err < 0) goto out; - err = mpls_route_add(cfg); + err = mpls_route_add(cfg, extack); out: kfree(cfg); diff --git a/net/mpls/internal.h b/net/mpls/internal.h index e59f299ceb3f..a015a6a1143b 100644 --- a/net/mpls/internal.h +++ b/net/mpls/internal.h @@ -205,7 +205,7 @@ int nla_put_labels(struct sk_buff *skb, int attrtype, u8 labels, int nla_get_labels(const struct nlattr *nla, u8 max_labels, u8 *labels, u32 label[], struct netlink_ext_ack *extack); int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table, - u8 via[]); + u8 via[], struct netlink_ext_ack *extack); bool mpls_output_possible(const struct net_device *dev); unsigned int mpls_dev_mtu(const struct net_device *dev); bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu); -- cgit v1.2.3