From 1b5aaa4b16f6e6471ab1c07b38068197a1b4c395 Mon Sep 17 00:00:00 2001 From: Jonas Gorski Date: Fri, 24 May 2013 14:40:54 +0200 Subject: [PATCH 1/2] ipv6: allow rejecting with "source address failed policy" RFC6204 L-14 requires rejecting traffic from invalid addresses with ICMPv6 Destination Unreachable, Code 5 (Source address failed ingress/ egress policy) on the LAN side, so add an appropriate rule for that. Signed-off-by: Jonas Gorski --- include/net/netns/ipv6.h | 1 + include/uapi/linux/fib_rules.h | 4 +++ include/uapi/linux/rtnetlink.h | 1 + net/ipv4/fib_semantics.c | 4 +++ net/ipv4/fib_trie.c | 1 + net/ipv4/ipmr.c | 1 + net/ipv6/fib6_rules.c | 4 +++ net/ipv6/ip6mr.c | 2 ++ net/ipv6/route.c | 58 +++++++++++++++++++++++++++++++++++++++++- 9 files changed, 75 insertions(+), 1 deletion(-) --- a/include/net/netns/ipv6.h +++ b/include/net/netns/ipv6.h @@ -57,6 +57,7 @@ struct netns_ipv6 { unsigned long ip6_rt_last_gc; #ifdef CONFIG_IPV6_MULTIPLE_TABLES struct rt6_info *ip6_prohibit_entry; + struct rt6_info *ip6_policy_failed_entry; struct rt6_info *ip6_blk_hole_entry; struct fib6_table *fib6_local_tbl; struct fib_rules_ops *fib6_rules_ops; --- a/include/uapi/linux/fib_rules.h +++ b/include/uapi/linux/fib_rules.h @@ -64,6 +64,10 @@ enum { FR_ACT_BLACKHOLE, /* Drop without notification */ FR_ACT_UNREACHABLE, /* Drop with ENETUNREACH */ FR_ACT_PROHIBIT, /* Drop with EACCES */ + FR_ACT_RES9, + FR_ACT_RES10, + FR_ACT_RES11, + FR_ACT_POLICY_FAILED, /* Drop with EACCES */ __FR_ACT_MAX, }; --- a/include/uapi/linux/rtnetlink.h +++ b/include/uapi/linux/rtnetlink.h @@ -203,6 +203,7 @@ enum { RTN_THROW, /* Not in this table */ RTN_NAT, /* Translate this address */ RTN_XRESOLVE, /* Use external resolver */ + RTN_POLICY_FAILED, /* Failed ingress/egress policy */ __RTN_MAX }; --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -138,6 +138,10 @@ const struct fib_prop fib_props[RTN_MAX .error = -EINVAL, .scope = RT_SCOPE_NOWHERE, }, + [RTN_POLICY_FAILED] = { + .error = -EACCES, + .scope = RT_SCOPE_UNIVERSE, + }, }; static void rt_fibinfo_free(struct rtable __rcu **rtp) --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -2324,6 +2324,7 @@ static const char *const rtn_type_names[ [RTN_THROW] = "THROW", [RTN_NAT] = "NAT", [RTN_XRESOLVE] = "XRESOLVE", + [RTN_POLICY_FAILED] = "POLICY_FAILED", }; static inline const char *rtn_type(char *buf, size_t len, unsigned int t) --- a/net/ipv4/ipmr.c +++ b/net/ipv4/ipmr.c @@ -184,6 +184,7 @@ static int ipmr_rule_action(struct fib_r case FR_ACT_UNREACHABLE: return -ENETUNREACH; case FR_ACT_PROHIBIT: + case FR_ACT_POLICY_FAILED: return -EACCES; case FR_ACT_BLACKHOLE: default: --- a/net/ipv6/fib6_rules.c +++ b/net/ipv6/fib6_rules.c @@ -73,6 +73,10 @@ static int fib6_rule_action(struct fib_r err = -EACCES; rt = net->ipv6.ip6_prohibit_entry; goto discard_pkt; + case FR_ACT_POLICY_FAILED: + err = -EACCES; + rt = net->ipv6.ip6_policy_failed_entry; + goto discard_pkt; } table = fib6_get_table(net, rule->table); --- a/net/ipv6/ip6mr.c +++ b/net/ipv6/ip6mr.c @@ -169,6 +169,8 @@ static int ip6mr_rule_action(struct fib_ return -ENETUNREACH; case FR_ACT_PROHIBIT: return -EACCES; + case FR_ACT_POLICY_FAILED: + return -EACCES; case FR_ACT_BLACKHOLE: default: return -EINVAL; --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -87,6 +87,8 @@ static int ip6_pkt_discard(struct sk_bu static int ip6_pkt_discard_out(struct sk_buff *skb); static int ip6_pkt_prohibit(struct sk_buff *skb); static int ip6_pkt_prohibit_out(struct sk_buff *skb); +static int ip6_pkt_policy_failed(struct sk_buff *skb); +static int ip6_pkt_policy_failed_out(struct sk_buff *skb); static void ip6_link_failure(struct sk_buff *skb); static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb, u32 mtu); @@ -282,6 +284,21 @@ static const struct rt6_info ip6_prohibi .rt6i_ref = ATOMIC_INIT(1), }; +static const struct rt6_info ip6_policy_failed_entry_template = { + .dst = { + .__refcnt = ATOMIC_INIT(1), + .__use = 1, + .obsolete = DST_OBSOLETE_FORCE_CHK, + .error = -EACCES, + .input = ip6_pkt_policy_failed, + .output = ip6_pkt_policy_failed_out, + }, + .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP), + .rt6i_protocol = RTPROT_KERNEL, + .rt6i_metric = ~(u32) 0, + .rt6i_ref = ATOMIC_INIT(1), +}; + static const struct rt6_info ip6_blk_hole_entry_template = { .dst = { .__refcnt = ATOMIC_INIT(1), @@ -1595,6 +1612,11 @@ int ip6_route_add(struct fib6_config *cf rt->dst.output = ip6_pkt_prohibit_out; rt->dst.input = ip6_pkt_prohibit; break; + case RTN_POLICY_FAILED: + rt->dst.error = -EACCES; + rt->dst.output = ip6_pkt_policy_failed_out; + rt->dst.input = ip6_pkt_policy_failed; + break; case RTN_THROW: default: rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN @@ -2174,6 +2196,17 @@ static int ip6_pkt_prohibit_out(struct s return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES); } +static int ip6_pkt_policy_failed(struct sk_buff *skb) +{ + return ip6_pkt_drop(skb, ICMPV6_POLICY_FAIL, IPSTATS_MIB_INNOROUTES); +} + +static int ip6_pkt_policy_failed_out(struct sk_buff *skb) +{ + skb->dev = skb_dst(skb)->dev; + return ip6_pkt_drop(skb, ICMPV6_POLICY_FAIL, IPSTATS_MIB_OUTNOROUTES); +} + /* * Allocate a dst for local (unicast / anycast) address. */ @@ -2376,7 +2409,8 @@ static int rtm_to_fib6_config(struct sk_ if (rtm->rtm_type == RTN_UNREACHABLE || rtm->rtm_type == RTN_BLACKHOLE || rtm->rtm_type == RTN_PROHIBIT || - rtm->rtm_type == RTN_THROW) + rtm->rtm_type == RTN_THROW || + rtm->rtm_type == RTN_POLICY_FAILED) cfg->fc_flags |= RTF_REJECT; if (rtm->rtm_type == RTN_LOCAL) @@ -2578,6 +2612,9 @@ static int rt6_fill_node(struct net *net case -EACCES: rtm->rtm_type = RTN_PROHIBIT; break; + case -EPERM: + rtm->rtm_type = RTN_POLICY_FAILED; + break; case -EAGAIN: rtm->rtm_type = RTN_THROW; break; @@ -2828,6 +2865,8 @@ static int ip6_route_dev_notify(struct n #ifdef CONFIG_IPV6_MULTIPLE_TABLES net->ipv6.ip6_prohibit_entry->dst.dev = dev; net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev); + net->ipv6.ip6_policy_failed_entry->dst.dev = dev; + net->ipv6.ip6_policy_failed_entry->rt6i_idev = in6_dev_get(dev); net->ipv6.ip6_blk_hole_entry->dst.dev = dev; net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev); #endif @@ -3044,6 +3083,17 @@ static int __net_init ip6_route_net_init net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops; dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst, ip6_template_metrics, true); + + net->ipv6.ip6_policy_failed_entry = + kmemdup(&ip6_policy_failed_entry_template, + sizeof(*net->ipv6.ip6_policy_failed_entry), GFP_KERNEL); + if (!net->ipv6.ip6_policy_failed_entry) + goto out_ip6_blk_hole_entry; + net->ipv6.ip6_policy_failed_entry->dst.path = + (struct dst_entry *)net->ipv6.ip6_policy_failed_entry; + net->ipv6.ip6_policy_failed_entry->dst.ops = &net->ipv6.ip6_dst_ops; + dst_init_metrics(&net->ipv6.ip6_policy_failed_entry->dst, + ip6_template_metrics, true); #endif net->ipv6.sysctl.flush_delay = 0; @@ -3062,6 +3112,8 @@ out: return ret; #ifdef CONFIG_IPV6_MULTIPLE_TABLES +out_ip6_blk_hole_entry: + kfree(net->ipv6.ip6_blk_hole_entry); out_ip6_prohibit_entry: kfree(net->ipv6.ip6_prohibit_entry); out_ip6_null_entry: @@ -3079,6 +3131,7 @@ static void __net_exit ip6_route_net_exi #ifdef CONFIG_IPV6_MULTIPLE_TABLES kfree(net->ipv6.ip6_prohibit_entry); kfree(net->ipv6.ip6_blk_hole_entry); + kfree(net->ipv6.ip6_policy_failed_entry); #endif dst_entries_destroy(&net->ipv6.ip6_dst_ops); } @@ -3175,6 +3228,9 @@ int __init ip6_route_init(void) init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev; init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev); + init_net.ipv6.ip6_policy_failed_entry->dst.dev = init_net.loopback_dev; + init_net.ipv6.ip6_policy_failed_entry->rt6i_idev = + in6_dev_get(init_net.loopback_dev); #endif ret = fib6_init(); if (ret) 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306