From fadf6bf06069138f8e97c9a963be38348ba2708b Mon Sep 17 00:00:00 2001 From: "Templin, Fred L" Date: Tue, 11 Mar 2008 18:35:59 -0400 Subject: [PATCH] [IPV6] SIT: Add PRL management for ISATAP. This patch updates the Linux the Intra-Site Automatic Tunnel Addressing Protocol (ISATAP) implementation. It places the ISATAP potential router list (PRL) in the kernel and adds three new private ioctls for PRL management. [Add several changes of structure name, constant names etc. - yoshfuji] Signed-off-by: Fred L. Templin Signed-off-by: YOSHIFUJI Hideaki --- include/linux/if_tunnel.h | 18 +++- include/linux/skbuff.h | 3 +- include/net/ipip.h | 7 ++ include/net/ndisc.h | 9 ++ net/ipv6/ndisc.c | 24 +++++ net/ipv6/route.c | 2 - net/ipv6/sit.c | 186 +++++++++++++++++++++++++++++--------- 7 files changed, 199 insertions(+), 50 deletions(-) diff --git a/include/linux/if_tunnel.h b/include/linux/if_tunnel.h index 228eb4eb31..f20c224d54 100644 --- a/include/linux/if_tunnel.h +++ b/include/linux/if_tunnel.h @@ -7,6 +7,9 @@ #define SIOCADDTUNNEL (SIOCDEVPRIVATE + 1) #define SIOCDELTUNNEL (SIOCDEVPRIVATE + 2) #define SIOCCHGTUNNEL (SIOCDEVPRIVATE + 3) +#define SIOCADDPRL (SIOCDEVPRIVATE + 5) +#define SIOCDELPRL (SIOCDEVPRIVATE + 6) +#define SIOCCHGPRL (SIOCDEVPRIVATE + 7) #define GRE_CSUM __constant_htons(0x8000) #define GRE_ROUTING __constant_htons(0x4000) @@ -17,9 +20,6 @@ #define GRE_FLAGS __constant_htons(0x00F8) #define GRE_VERSION __constant_htons(0x0007) -/* i_flags values for SIT mode */ -#define SIT_ISATAP 0x0001 - struct ip_tunnel_parm { char name[IFNAMSIZ]; @@ -31,4 +31,16 @@ struct ip_tunnel_parm struct iphdr iph; }; +/* SIT-mode i_flags */ +#define SIT_ISATAP 0x0001 + +struct ip_tunnel_prl { + __be32 addr; + __u16 flags; + __u16 __reserved; +}; + +/* PRL flags */ +#define PRL_DEFAULT 0x0001 + #endif /* _IF_TUNNEL_H_ */ diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index ff72145d5d..e10e55c9b0 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -313,7 +313,8 @@ struct sk_buff { __u16 tc_verd; /* traffic control verdict */ #endif #endif - /* 2 byte hole */ + __u8 ndisc_nodetype:2; + /* 14 bit hole */ #ifdef CONFIG_NET_DMA dma_cookie_t dma_cookie; diff --git a/include/net/ipip.h b/include/net/ipip.h index 549e132bca..205536a014 100644 --- a/include/net/ipip.h +++ b/include/net/ipip.h @@ -24,6 +24,13 @@ struct ip_tunnel int mlink; struct ip_tunnel_parm parms; + struct ip_tunnel_prl_entry *prl; /* potential router list */ +}; + +struct ip_tunnel_prl_entry +{ + struct ip_tunnel_prl_entry *next; + struct ip_tunnel_prl entry; }; #define IPTUNNEL_XMIT() do { \ diff --git a/include/net/ndisc.h b/include/net/ndisc.h index 5aedf324de..9f2bae68d2 100644 --- a/include/net/ndisc.h +++ b/include/net/ndisc.h @@ -11,6 +11,15 @@ #define NDISC_NEIGHBOUR_ADVERTISEMENT 136 #define NDISC_REDIRECT 137 +/* + * Router type: cross-layer information from link-layer to + * IPv6 layer reported by certain link types (e.g., RFC4214). + */ +#define NDISC_NODETYPE_UNSPEC 0 /* unspecified (default) */ +#define NDISC_NODETYPE_HOST 1 /* host or unauthorized router */ +#define NDISC_NODETYPE_NODEFAULT 2 /* non-default router */ +#define NDISC_NODETYPE_DEFAULT 3 /* default router */ + /* * ndisc options */ diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index 510aa747a4..53b546019f 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -1092,6 +1092,12 @@ static void ndisc_router_discovery(struct sk_buff *skb) return; } + if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) { + ND_PRINTK2(KERN_WARNING + "ICMPv6 RA: from host or unauthorized router\n"); + return; + } + /* * set the RA_RECV flag in the interface */ @@ -1115,6 +1121,10 @@ static void ndisc_router_discovery(struct sk_buff *skb) return; } + /* skip link-specific parameters from interior routers */ + if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) + goto skip_linkparms; + if (in6_dev->if_flags & IF_RS_SENT) { /* * flag that an RA was received after an RS was sent @@ -1229,6 +1239,8 @@ skip_defrtr: } } +skip_linkparms: + /* * Process options. */ @@ -1268,6 +1280,10 @@ skip_defrtr: } #endif + /* skip link-specific ndopts from interior routers */ + if (skb->ndisc_nodetype == NDISC_NODETYPE_NODEFAULT) + goto out; + if (in6_dev->cnf.accept_ra_pinfo && ndopts.nd_opts_pi) { struct nd_opt_hdr *p; for (p = ndopts.nd_opts_pi; @@ -1331,6 +1347,14 @@ static void ndisc_redirect_rcv(struct sk_buff *skb) int optlen; u8 *lladdr = NULL; + switch (skb->ndisc_nodetype) { + case NDISC_NODETYPE_HOST: + case NDISC_NODETYPE_NODEFAULT: + ND_PRINTK2(KERN_WARNING + "ICMPv6 Redirect: from host or unauthorized router\n"); + return; + } + if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { ND_PRINTK2(KERN_WARNING "ICMPv6 Redirect: source address is not link-local.\n"); diff --git a/net/ipv6/route.c b/net/ipv6/route.c index cd82b6db35..f17b2f6189 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1699,8 +1699,6 @@ struct rt6_info *rt6_get_dflt_router(struct in6_addr *addr, struct net_device *d return rt; } -EXPORT_SYMBOL(rt6_get_dflt_router); - struct rt6_info *rt6_add_dflt_router(struct in6_addr *gwaddr, struct net_device *dev, unsigned int pref) diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c index 1b8196c8d1..4786419ade 100644 --- a/net/ipv6/sit.c +++ b/net/ipv6/sit.c @@ -16,7 +16,7 @@ * Changes: * Roger Venning : 6to4 support * Nate Thompson : 6to4 support - * Fred L. Templin : isatap support + * Fred Templin : isatap support */ #include @@ -197,6 +197,119 @@ failed: return NULL; } +static struct ip_tunnel_prl_entry * +ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr) +{ + struct ip_tunnel_prl_entry *p = (struct ip_tunnel_prl_entry *)NULL; + + for (p = t->prl; p; p = p->next) + if (p->entry.addr == addr) + break; + return p; + +} + +static int +ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg) +{ + struct ip_tunnel_prl_entry *p; + + for (p = t->prl; p; p = p->next) { + if (p->entry.addr == a->addr) { + if (chg) { + p->entry = *a; + return 0; + } + return -EEXIST; + } + } + + if (chg) + return -ENXIO; + + p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL); + if (!p) + return -ENOBUFS; + + p->entry = *a; + p->next = t->prl; + t->prl = p; + return 0; +} + +static int +ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a) +{ + struct ip_tunnel_prl_entry *x, **p; + + if (a) { + for (p = &t->prl; *p; p = &(*p)->next) { + if ((*p)->entry.addr == a->addr) { + x = *p; + *p = x->next; + kfree(x); + return 0; + } + } + return -ENXIO; + } else { + while (t->prl) { + x = t->prl; + t->prl = t->prl->next; + kfree(x); + } + } + return 0; +} + +/* copied directly from anycast.c */ +static int +ipip6_onlink(struct in6_addr *addr, struct net_device *dev) +{ + struct inet6_dev *idev; + struct inet6_ifaddr *ifa; + int onlink; + + onlink = 0; + rcu_read_lock(); + idev = __in6_dev_get(dev); + if (idev) { + read_lock_bh(&idev->lock); + for (ifa=idev->addr_list; ifa; ifa=ifa->if_next) { + onlink = ipv6_prefix_equal(addr, &ifa->addr, + ifa->prefix_len); + if (onlink) + break; + } + read_unlock_bh(&idev->lock); + } + rcu_read_unlock(); + return onlink; +} + +static int +isatap_chksrc(struct sk_buff *skb, struct iphdr *iph, struct ip_tunnel *t) +{ + struct ip_tunnel_prl_entry *p = ipip6_tunnel_locate_prl(t, iph->saddr); + int ok = 1; + + if (p) { + if (p->entry.flags & PRL_DEFAULT) + skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT; + else + skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT; + } else { + struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr; + if (ipv6_addr_is_isatap(addr6) && + (addr6->s6_addr32[3] == iph->saddr) && + ipip6_onlink(addr6, t->dev)) + skb->ndisc_nodetype = NDISC_NODETYPE_HOST; + else + ok = 0; + } + return ok; +} + static void ipip6_tunnel_uninit(struct net_device *dev) { if (dev == ipip6_fb_tunnel_dev) { @@ -206,6 +319,7 @@ static void ipip6_tunnel_uninit(struct net_device *dev) dev_put(dev); } else { ipip6_tunnel_unlink(netdev_priv(dev)); + ipip6_tunnel_del_prl(netdev_priv(dev), 0); dev_put(dev); } } @@ -365,48 +479,6 @@ static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb) IP6_ECN_set_ce(ipv6_hdr(skb)); } -/* ISATAP (RFC4214) - check source address */ -static int -isatap_srcok(struct sk_buff *skb, struct iphdr *iph, struct net_device *dev) -{ - struct neighbour *neigh; - struct dst_entry *dst; - struct rt6_info *rt; - struct flowi fl; - struct in6_addr *addr6; - struct in6_addr rtr; - struct ipv6hdr *iph6; - int ok = 0; - - /* from onlink default router */ - ipv6_addr_set(&rtr, htonl(0xFE800000), 0, 0, 0); - ipv6_isatap_eui64(rtr.s6_addr + 8, iph->saddr); - if ((rt = rt6_get_dflt_router(&rtr, dev))) { - dst_release(&rt->u.dst); - return 1; - } - - iph6 = ipv6_hdr(skb); - memset(&fl, 0, sizeof(fl)); - fl.proto = iph6->nexthdr; - ipv6_addr_copy(&fl.fl6_dst, &iph6->saddr); - fl.oif = dev->ifindex; - security_skb_classify_flow(skb, &fl); - - dst = ip6_route_output(&init_net, NULL, &fl); - if (!dst->error && (dst->dev == dev) && (neigh = dst->neighbour)) { - - addr6 = (struct in6_addr*)&neigh->primary_key; - - /* from correct previous hop */ - if (ipv6_addr_is_isatap(addr6) && - (addr6->s6_addr32[3] == iph->saddr)) - ok = 1; - } - dst_release(dst); - return ok; -} - static int ipip6_rcv(struct sk_buff *skb) { struct iphdr *iph; @@ -427,7 +499,7 @@ static int ipip6_rcv(struct sk_buff *skb) skb->pkt_type = PACKET_HOST; if ((tunnel->dev->priv_flags & IFF_ISATAP) && - !isatap_srcok(skb, iph, tunnel->dev)) { + !isatap_chksrc(skb, iph, tunnel)) { tunnel->stat.rx_errors++; read_unlock(&ipip6_lock); kfree_skb(skb); @@ -707,6 +779,7 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd) { int err = 0; struct ip_tunnel_parm p; + struct ip_tunnel_prl prl; struct ip_tunnel *t; switch (cmd) { @@ -806,6 +879,31 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd) err = 0; break; + case SIOCADDPRL: + case SIOCDELPRL: + case SIOCCHGPRL: + err = -EPERM; + if (!capable(CAP_NET_ADMIN)) + goto done; + err = -EINVAL; + if (dev == ipip6_fb_tunnel_dev) + goto done; + err = -EFAULT; + if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl))) + goto done; + err = -ENOENT; + if (!(t = netdev_priv(dev))) + goto done; + + ipip6_tunnel_unlink(t); + if (cmd == SIOCDELPRL) + err = ipip6_tunnel_del_prl(t, &prl); + else + err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL); + ipip6_tunnel_link(t); + netdev_state_change(dev); + break; + default: err = -EINVAL; } -- 2.39.5