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authorRoland McGrath <roland@gnu.org>2000-02-04 03:21:18 +0000
committerRoland McGrath <roland@gnu.org>2000-02-04 03:21:18 +0000
commit9fd51e9b0ad33a89a83fdbbb66bd20d85f7893fb (patch)
tree8845b79f170028cb4380045c50277bbf075b5b7d /pfinet/linux-src/net/ipv4/fib_semantics.c
Import of Linux 2.2.12 subset (ipv4 stack and related)
Diffstat (limited to 'pfinet/linux-src/net/ipv4/fib_semantics.c')
-rw-r--r--pfinet/linux-src/net/ipv4/fib_semantics.c991
1 files changed, 991 insertions, 0 deletions
diff --git a/pfinet/linux-src/net/ipv4/fib_semantics.c b/pfinet/linux-src/net/ipv4/fib_semantics.c
new file mode 100644
index 00000000..b78f7eba
--- /dev/null
+++ b/pfinet/linux-src/net/ipv4/fib_semantics.c
@@ -0,0 +1,991 @@
+/*
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * IPv4 Forwarding Information Base: semantics.
+ *
+ * Version: $Id: fib_semantics.c,v 1.13 1999/03/21 05:22:34 davem Exp $
+ *
+ * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/config.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/bitops.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/errno.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/if_arp.h>
+#include <linux/proc_fs.h>
+#include <linux/skbuff.h>
+#include <linux/netlink.h>
+#include <linux/init.h>
+
+#include <net/ip.h>
+#include <net/protocol.h>
+#include <net/route.h>
+#include <net/tcp.h>
+#include <net/sock.h>
+#include <net/ip_fib.h>
+
+#define FSprintk(a...)
+
+static struct fib_info *fib_info_list;
+
+#define for_fib_info() { struct fib_info *fi; \
+ for (fi = fib_info_list; fi; fi = fi->fib_next)
+
+#define endfor_fib_info() }
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+
+#define for_nexthops(fi) { int nhsel; const struct fib_nh * nh; \
+for (nhsel=0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)
+
+#define change_nexthops(fi) { int nhsel; struct fib_nh * nh; \
+for (nhsel=0, nh = (struct fib_nh*)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nh++, nhsel++)
+
+#else /* CONFIG_IP_ROUTE_MULTIPATH */
+
+/* Hope, that gcc will optimize it to get rid of dummy loop */
+
+#define for_nexthops(fi) { int nhsel=0; const struct fib_nh * nh = (fi)->fib_nh; \
+for (nhsel=0; nhsel < 1; nhsel++)
+
+#define change_nexthops(fi) { int nhsel=0; struct fib_nh * nh = (struct fib_nh*)((fi)->fib_nh); \
+for (nhsel=0; nhsel < 1; nhsel++)
+
+#endif /* CONFIG_IP_ROUTE_MULTIPATH */
+
+#define endfor_nexthops(fi) }
+
+
+static struct
+{
+ int error;
+ u8 scope;
+} fib_props[RTA_MAX+1] = {
+ { 0, RT_SCOPE_NOWHERE}, /* RTN_UNSPEC */
+ { 0, RT_SCOPE_UNIVERSE}, /* RTN_UNICAST */
+ { 0, RT_SCOPE_HOST}, /* RTN_LOCAL */
+ { 0, RT_SCOPE_LINK}, /* RTN_BROADCAST */
+ { 0, RT_SCOPE_LINK}, /* RTN_ANYCAST */
+ { 0, RT_SCOPE_UNIVERSE}, /* RTN_MULTICAST */
+ { -EINVAL, RT_SCOPE_UNIVERSE}, /* RTN_BLACKHOLE */
+ { -EHOSTUNREACH, RT_SCOPE_UNIVERSE},/* RTN_UNREACHABLE */
+ { -EACCES, RT_SCOPE_UNIVERSE}, /* RTN_PROHIBIT */
+ { -EAGAIN, RT_SCOPE_UNIVERSE}, /* RTN_THROW */
+#ifdef CONFIG_IP_ROUTE_NAT
+ { 0, RT_SCOPE_HOST}, /* RTN_NAT */
+#else
+ { -EINVAL, RT_SCOPE_NOWHERE}, /* RTN_NAT */
+#endif
+ { -EINVAL, RT_SCOPE_NOWHERE} /* RTN_XRESOLVE */
+};
+
+/* Release a nexthop info record */
+
+void fib_release_info(struct fib_info *fi)
+{
+ if (fi && !--fi->fib_refcnt) {
+ if (fi->fib_next)
+ fi->fib_next->fib_prev = fi->fib_prev;
+ if (fi->fib_prev)
+ fi->fib_prev->fib_next = fi->fib_next;
+ if (fi == fib_info_list)
+ fib_info_list = fi->fib_next;
+ kfree(fi);
+ }
+}
+
+extern __inline__ int nh_comp(const struct fib_info *fi, const struct fib_info *ofi)
+{
+ const struct fib_nh *onh = ofi->fib_nh;
+
+ for_nexthops(fi) {
+ if (nh->nh_oif != onh->nh_oif ||
+ nh->nh_gw != onh->nh_gw ||
+ nh->nh_scope != onh->nh_scope ||
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ nh->nh_weight != onh->nh_weight ||
+#endif
+#ifdef CONFIG_NET_CLS_ROUTE
+ nh->nh_tclassid != onh->nh_tclassid ||
+#endif
+ ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
+ return -1;
+ onh++;
+ } endfor_nexthops(fi);
+ return 0;
+}
+
+extern __inline__ struct fib_info * fib_find_info(const struct fib_info *nfi)
+{
+ for_fib_info() {
+ if (fi->fib_nhs != nfi->fib_nhs)
+ continue;
+ if (nfi->fib_protocol == fi->fib_protocol &&
+ nfi->fib_prefsrc == fi->fib_prefsrc &&
+ nfi->fib_priority == fi->fib_priority &&
+ nfi->fib_mtu == fi->fib_mtu &&
+ nfi->fib_rtt == fi->fib_rtt &&
+ nfi->fib_window == fi->fib_window &&
+ ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
+ (nfi->fib_nhs == 0 || nh_comp(fi, nfi) == 0))
+ return fi;
+ } endfor_fib_info();
+ return NULL;
+}
+
+/* Check, that the gateway is already configured.
+ Used only by redirect accept routine.
+ */
+
+int ip_fib_check_default(u32 gw, struct device *dev)
+{
+ for_fib_info() {
+ if (fi->fib_flags & RTNH_F_DEAD)
+ continue;
+ for_nexthops(fi) {
+ if (nh->nh_dev == dev && nh->nh_gw == gw &&
+ !(nh->nh_flags&RTNH_F_DEAD))
+ return 0;
+ } endfor_nexthops(fi);
+ } endfor_fib_info();
+ return -1;
+}
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+
+static u32 fib_get_attr32(struct rtattr *attr, int attrlen, int type)
+{
+ while (RTA_OK(attr,attrlen)) {
+ if (attr->rta_type == type)
+ return *(u32*)RTA_DATA(attr);
+ attr = RTA_NEXT(attr, attrlen);
+ }
+ return 0;
+}
+
+static int
+fib_count_nexthops(struct rtattr *rta)
+{
+ int nhs = 0;
+ struct rtnexthop *nhp = RTA_DATA(rta);
+ int nhlen = RTA_PAYLOAD(rta);
+
+ while (nhlen >= (int)sizeof(struct rtnexthop)) {
+ if ((nhlen -= nhp->rtnh_len) < 0)
+ return 0;
+ nhs++;
+ nhp = RTNH_NEXT(nhp);
+ };
+ return nhs;
+}
+
+static int
+fib_get_nhs(struct fib_info *fi, const struct rtattr *rta, const struct rtmsg *r)
+{
+ struct rtnexthop *nhp = RTA_DATA(rta);
+ int nhlen = RTA_PAYLOAD(rta);
+
+ change_nexthops(fi) {
+ int attrlen = nhlen - sizeof(struct rtnexthop);
+ if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
+ return -EINVAL;
+ nh->nh_flags = (r->rtm_flags&~0xFF) | nhp->rtnh_flags;
+ nh->nh_oif = nhp->rtnh_ifindex;
+ nh->nh_weight = nhp->rtnh_hops + 1;
+ if (attrlen) {
+ nh->nh_gw = fib_get_attr32(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
+#ifdef CONFIG_NET_CLS_ROUTE
+ nh->nh_tclassid = fib_get_attr32(RTNH_DATA(nhp), attrlen, RTA_FLOW);
+#endif
+ }
+ nhp = RTNH_NEXT(nhp);
+ } endfor_nexthops(fi);
+ return 0;
+}
+
+#endif
+
+int fib_nh_match(struct rtmsg *r, struct nlmsghdr *nlh, struct kern_rta *rta,
+ struct fib_info *fi)
+{
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ struct rtnexthop *nhp;
+ int nhlen;
+#endif
+
+ if (rta->rta_priority &&
+ *rta->rta_priority != fi->fib_priority)
+ return 1;
+
+ if (rta->rta_oif || rta->rta_gw) {
+ if ((!rta->rta_oif || *rta->rta_oif == fi->fib_nh->nh_oif) &&
+ (!rta->rta_gw || memcmp(rta->rta_gw, &fi->fib_nh->nh_gw, 4) == 0))
+ return 0;
+ return 1;
+ }
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ if (rta->rta_mp == NULL)
+ return 0;
+ nhp = RTA_DATA(rta->rta_mp);
+ nhlen = RTA_PAYLOAD(rta->rta_mp);
+
+ for_nexthops(fi) {
+ int attrlen = nhlen - sizeof(struct rtnexthop);
+ u32 gw;
+
+ if (attrlen < 0 || (nhlen -= nhp->rtnh_len) < 0)
+ return -EINVAL;
+ if (nhp->rtnh_ifindex && nhp->rtnh_ifindex != nh->nh_oif)
+ return 1;
+ if (attrlen) {
+ gw = fib_get_attr32(RTNH_DATA(nhp), attrlen, RTA_GATEWAY);
+ if (gw && gw != nh->nh_gw)
+ return 1;
+#ifdef CONFIG_NET_CLS_ROUTE
+ gw = fib_get_attr32(RTNH_DATA(nhp), attrlen, RTA_FLOW);
+ if (gw && gw != nh->nh_tclassid)
+ return 1;
+#endif
+ }
+ nhp = RTNH_NEXT(nhp);
+ } endfor_nexthops(fi);
+#endif
+ return 0;
+}
+
+
+/*
+ Picture
+ -------
+
+ Semantics of nexthop is very messy by historical reasons.
+ We have to take into account, that:
+ a) gateway can be actually local interface address,
+ so that gatewayed route is direct.
+ b) gateway must be on-link address, possibly
+ described not by an ifaddr, but also by a direct route.
+ c) If both gateway and interface are specified, they should not
+ contradict.
+ d) If we use tunnel routes, gateway could be not on-link.
+
+ Attempt to reconcile all of these (alas, self-contradictory) conditions
+ results in pretty ugly and hairy code with obscure logic.
+
+ I choosed to generalized it instead, so that the size
+ of code does not increase practically, but it becomes
+ much more general.
+ Every prefix is assigned a "scope" value: "host" is local address,
+ "link" is direct route,
+ [ ... "site" ... "interior" ... ]
+ and "universe" is true gateway route with global meaning.
+
+ Every prefix refers to a set of "nexthop"s (gw, oif),
+ where gw must have narrower scope. This recursion stops
+ when gw has LOCAL scope or if "nexthop" is declared ONLINK,
+ which means that gw is forced to be on link.
+
+ Code is still hairy, but now it is apparently logically
+ consistent and very flexible. F.e. as by-product it allows
+ to co-exists in peace independent exterior and interior
+ routing processes.
+
+ Normally it looks as following.
+
+ {universe prefix} -> (gw, oif) [scope link]
+ |
+ |-> {link prefix} -> (gw, oif) [scope local]
+ |
+ |-> {local prefix} (terminal node)
+ */
+
+static int fib_check_nh(const struct rtmsg *r, struct fib_info *fi, struct fib_nh *nh)
+{
+ int err;
+
+ if (nh->nh_gw) {
+ struct rt_key key;
+ struct fib_result res;
+
+#ifdef CONFIG_IP_ROUTE_PERVASIVE
+ if (nh->nh_flags&RTNH_F_PERVASIVE)
+ return 0;
+#endif
+ if (nh->nh_flags&RTNH_F_ONLINK) {
+ struct device *dev;
+
+ if (r->rtm_scope >= RT_SCOPE_LINK)
+ return -EINVAL;
+ if (inet_addr_type(nh->nh_gw) != RTN_UNICAST)
+ return -EINVAL;
+ if ((dev = dev_get_by_index(nh->nh_oif)) == NULL)
+ return -ENODEV;
+ if (!(dev->flags&IFF_UP))
+ return -ENETDOWN;
+ nh->nh_dev = dev;
+ nh->nh_scope = RT_SCOPE_LINK;
+ return 0;
+ }
+ memset(&key, 0, sizeof(key));
+ key.dst = nh->nh_gw;
+ key.oif = nh->nh_oif;
+ key.scope = r->rtm_scope + 1;
+
+ /* It is not necessary, but requires a bit of thinking */
+ if (key.scope < RT_SCOPE_LINK)
+ key.scope = RT_SCOPE_LINK;
+
+ if ((err = fib_lookup(&key, &res)) != 0)
+ return err;
+ nh->nh_scope = res.scope;
+ nh->nh_oif = FIB_RES_OIF(res);
+ nh->nh_dev = FIB_RES_DEV(res);
+ } else {
+ struct in_device *in_dev;
+
+ if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
+ return -EINVAL;
+
+ in_dev = inetdev_by_index(nh->nh_oif);
+ if (in_dev == NULL)
+ return -ENODEV;
+ if (!(in_dev->dev->flags&IFF_UP))
+ return -ENETDOWN;
+ nh->nh_dev = in_dev->dev;
+ nh->nh_scope = RT_SCOPE_HOST;
+ }
+ return 0;
+}
+
+struct fib_info *
+fib_create_info(const struct rtmsg *r, struct kern_rta *rta,
+ const struct nlmsghdr *nlh, int *errp)
+{
+ int err;
+ struct fib_info *fi = NULL;
+ struct fib_info *ofi;
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ int nhs = 1;
+#else
+ const int nhs = 1;
+#endif
+
+ /* Fast check to catch the most weird cases */
+ if (fib_props[r->rtm_type].scope > r->rtm_scope)
+ goto err_inval;
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ if (rta->rta_mp) {
+ nhs = fib_count_nexthops(rta->rta_mp);
+ if (nhs == 0)
+ goto err_inval;
+ }
+#endif
+
+ fi = kmalloc(sizeof(*fi)+nhs*sizeof(struct fib_nh), GFP_KERNEL);
+ err = -ENOBUFS;
+ if (fi == NULL)
+ goto failure;
+ memset(fi, 0, sizeof(*fi)+nhs*sizeof(struct fib_nh));
+
+ fi->fib_protocol = r->rtm_protocol;
+ fi->fib_nhs = nhs;
+ fi->fib_flags = r->rtm_flags;
+ if (rta->rta_priority)
+ fi->fib_priority = *rta->rta_priority;
+ if (rta->rta_mx) {
+ int attrlen = RTA_PAYLOAD(rta->rta_mx);
+ struct rtattr *attr = RTA_DATA(rta->rta_mx);
+
+ while (RTA_OK(attr, attrlen)) {
+ unsigned flavor = attr->rta_type;
+ if (flavor) {
+ if (flavor > FIB_MAX_METRICS)
+ goto err_inval;
+ fi->fib_metrics[flavor-1] = *(unsigned*)RTA_DATA(attr);
+ }
+ attr = RTA_NEXT(attr, attrlen);
+ }
+ }
+ if (rta->rta_prefsrc)
+ memcpy(&fi->fib_prefsrc, rta->rta_prefsrc, 4);
+
+ if (rta->rta_mp) {
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ if ((err = fib_get_nhs(fi, rta->rta_mp, r)) != 0)
+ goto failure;
+ if (rta->rta_oif && fi->fib_nh->nh_oif != *rta->rta_oif)
+ goto err_inval;
+ if (rta->rta_gw && memcmp(&fi->fib_nh->nh_gw, rta->rta_gw, 4))
+ goto err_inval;
+#ifdef CONFIG_NET_CLS_ROUTE
+ if (rta->rta_flow && memcmp(&fi->fib_nh->nh_tclassid, rta->rta_flow, 4))
+ goto err_inval;
+#endif
+#else
+ goto err_inval;
+#endif
+ } else {
+ struct fib_nh *nh = fi->fib_nh;
+ if (rta->rta_oif)
+ nh->nh_oif = *rta->rta_oif;
+ if (rta->rta_gw)
+ memcpy(&nh->nh_gw, rta->rta_gw, 4);
+#ifdef CONFIG_NET_CLS_ROUTE
+ if (rta->rta_flow)
+ memcpy(&nh->nh_tclassid, rta->rta_flow, 4);
+#endif
+ nh->nh_flags = r->rtm_flags;
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ nh->nh_weight = 1;
+#endif
+ }
+
+#ifdef CONFIG_IP_ROUTE_NAT
+ if (r->rtm_type == RTN_NAT) {
+ if (rta->rta_gw == NULL || nhs != 1 || rta->rta_oif)
+ goto err_inval;
+ memcpy(&fi->fib_nh->nh_gw, rta->rta_gw, 4);
+ goto link_it;
+ }
+#endif
+
+ if (fib_props[r->rtm_type].error) {
+ if (rta->rta_gw || rta->rta_oif || rta->rta_mp)
+ goto err_inval;
+ goto link_it;
+ }
+
+ if (r->rtm_scope > RT_SCOPE_HOST)
+ goto err_inval;
+
+ if (r->rtm_scope == RT_SCOPE_HOST) {
+ struct fib_nh *nh = fi->fib_nh;
+
+ /* Local address is added. */
+ if (nhs != 1 || nh->nh_gw)
+ goto err_inval;
+ nh->nh_scope = RT_SCOPE_NOWHERE;
+ nh->nh_dev = dev_get_by_index(fi->fib_nh->nh_oif);
+ err = -ENODEV;
+ if (nh->nh_dev == NULL)
+ goto failure;
+ } else {
+ change_nexthops(fi) {
+ if ((err = fib_check_nh(r, fi, nh)) != 0)
+ goto failure;
+ } endfor_nexthops(fi)
+ }
+
+ if (fi->fib_prefsrc) {
+ if (r->rtm_type != RTN_LOCAL || rta->rta_dst == NULL ||
+ memcmp(&fi->fib_prefsrc, rta->rta_dst, 4))
+ if (inet_addr_type(fi->fib_prefsrc) != RTN_LOCAL)
+ goto err_inval;
+ }
+
+link_it:
+ if ((ofi = fib_find_info(fi)) != NULL) {
+ kfree(fi);
+ ofi->fib_refcnt++;
+ return ofi;
+ }
+
+ fi->fib_refcnt++;
+ fi->fib_next = fib_info_list;
+ fi->fib_prev = NULL;
+ if (fib_info_list)
+ fib_info_list->fib_prev = fi;
+ fib_info_list = fi;
+ return fi;
+
+err_inval:
+ err = -EINVAL;
+
+failure:
+ *errp = err;
+ if (fi)
+ kfree(fi);
+ return NULL;
+}
+
+int
+fib_semantic_match(int type, struct fib_info *fi, const struct rt_key *key, struct fib_result *res)
+{
+ int err = fib_props[type].error;
+
+ if (err == 0) {
+ if (fi->fib_flags&RTNH_F_DEAD)
+ return 1;
+
+ res->fi = fi;
+
+ switch (type) {
+#ifdef CONFIG_IP_ROUTE_NAT
+ case RTN_NAT:
+ FIB_RES_RESET(*res);
+ return 0;
+#endif
+ case RTN_UNICAST:
+ case RTN_LOCAL:
+ case RTN_BROADCAST:
+ case RTN_ANYCAST:
+ case RTN_MULTICAST:
+ for_nexthops(fi) {
+ if (nh->nh_flags&RTNH_F_DEAD)
+ continue;
+ if (!key->oif || key->oif == nh->nh_oif)
+ break;
+ }
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ if (nhsel < fi->fib_nhs) {
+ res->nh_sel = nhsel;
+ return 0;
+ }
+#else
+ if (nhsel < 1)
+ return 0;
+#endif
+ endfor_nexthops(fi);
+ return 1;
+ default:
+ printk(KERN_DEBUG "impossible 102\n");
+ return -EINVAL;
+ }
+ }
+ return err;
+}
+
+/* Find appropriate source address to this destination */
+
+u32 __fib_res_prefsrc(struct fib_result *res)
+{
+ return inet_select_addr(FIB_RES_DEV(*res), FIB_RES_GW(*res), res->scope);
+}
+
+#ifdef CONFIG_RTNETLINK
+
+int
+fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
+ u8 tb_id, u8 type, u8 scope, void *dst, int dst_len, u8 tos,
+ struct fib_info *fi)
+{
+ struct rtmsg *rtm;
+ struct nlmsghdr *nlh;
+ unsigned char *b = skb->tail;
+
+ nlh = NLMSG_PUT(skb, pid, seq, event, sizeof(*rtm));
+ rtm = NLMSG_DATA(nlh);
+ rtm->rtm_family = AF_INET;
+ rtm->rtm_dst_len = dst_len;
+ rtm->rtm_src_len = 0;
+ rtm->rtm_tos = tos;
+ rtm->rtm_table = tb_id;
+ rtm->rtm_type = type;
+ rtm->rtm_flags = fi->fib_flags;
+ rtm->rtm_scope = scope;
+ if (rtm->rtm_dst_len)
+ RTA_PUT(skb, RTA_DST, 4, dst);
+ rtm->rtm_protocol = fi->fib_protocol;
+ if (fi->fib_priority)
+ RTA_PUT(skb, RTA_PRIORITY, 4, &fi->fib_priority);
+#ifdef CONFIG_NET_CLS_ROUTE
+ if (fi->fib_nh[0].nh_tclassid)
+ RTA_PUT(skb, RTA_FLOW, 4, &fi->fib_nh[0].nh_tclassid);
+#endif
+ if (fi->fib_mtu || fi->fib_window || fi->fib_rtt) {
+ int i;
+ struct rtattr *mx = (struct rtattr *)skb->tail;
+ RTA_PUT(skb, RTA_METRICS, 0, NULL);
+ for (i=0; i<FIB_MAX_METRICS; i++) {
+ if (fi->fib_metrics[i])
+ RTA_PUT(skb, i+1, sizeof(unsigned), fi->fib_metrics + i);
+ }
+ mx->rta_len = skb->tail - (u8*)mx;
+ }
+ if (fi->fib_prefsrc)
+ RTA_PUT(skb, RTA_PREFSRC, 4, &fi->fib_prefsrc);
+ if (fi->fib_nhs == 1) {
+ if (fi->fib_nh->nh_gw)
+ RTA_PUT(skb, RTA_GATEWAY, 4, &fi->fib_nh->nh_gw);
+ if (fi->fib_nh->nh_oif)
+ RTA_PUT(skb, RTA_OIF, sizeof(int), &fi->fib_nh->nh_oif);
+ }
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ if (fi->fib_nhs > 1) {
+ struct rtnexthop *nhp;
+ struct rtattr *mp_head;
+ if (skb_tailroom(skb) <= RTA_SPACE(0))
+ goto rtattr_failure;
+ mp_head = (struct rtattr*)skb_put(skb, RTA_SPACE(0));
+
+ for_nexthops(fi) {
+ if (skb_tailroom(skb) < RTA_ALIGN(RTA_ALIGN(sizeof(*nhp)) + 4))
+ goto rtattr_failure;
+ nhp = (struct rtnexthop*)skb_put(skb, RTA_ALIGN(sizeof(*nhp)));
+ nhp->rtnh_flags = nh->nh_flags & 0xFF;
+ nhp->rtnh_hops = nh->nh_weight-1;
+ nhp->rtnh_ifindex = nh->nh_oif;
+ if (nh->nh_gw)
+ RTA_PUT(skb, RTA_GATEWAY, 4, &nh->nh_gw);
+ nhp->rtnh_len = skb->tail - (unsigned char*)nhp;
+ } endfor_nexthops(fi);
+ mp_head->rta_type = RTA_MULTIPATH;
+ mp_head->rta_len = skb->tail - (u8*)mp_head;
+ }
+#endif
+ nlh->nlmsg_len = skb->tail - b;
+ return skb->len;
+
+nlmsg_failure:
+rtattr_failure:
+ skb_trim(skb, b - skb->data);
+ return -1;
+}
+
+#endif /* CONFIG_RTNETLINK */
+
+#ifndef CONFIG_IP_NOSIOCRT
+
+int
+fib_convert_rtentry(int cmd, struct nlmsghdr *nl, struct rtmsg *rtm,
+ struct kern_rta *rta, struct rtentry *r)
+{
+ int plen;
+ u32 *ptr;
+
+ memset(rtm, 0, sizeof(*rtm));
+ memset(rta, 0, sizeof(*rta));
+
+ if (r->rt_dst.sa_family != AF_INET)
+ return -EAFNOSUPPORT;
+
+ /* Check mask for validity:
+ a) it must be contiguous.
+ b) destination must have all host bits clear.
+ c) if application forgot to set correct family (AF_INET),
+ reject request unless it is absolutely clear i.e.
+ both family and mask are zero.
+ */
+ plen = 32;
+ ptr = &((struct sockaddr_in*)&r->rt_dst)->sin_addr.s_addr;
+ if (!(r->rt_flags&RTF_HOST)) {
+ u32 mask = ((struct sockaddr_in*)&r->rt_genmask)->sin_addr.s_addr;
+ if (r->rt_genmask.sa_family != AF_INET) {
+ if (mask || r->rt_genmask.sa_family)
+ return -EAFNOSUPPORT;
+ }
+ if (bad_mask(mask, *ptr))
+ return -EINVAL;
+ plen = inet_mask_len(mask);
+ }
+
+ nl->nlmsg_flags = NLM_F_REQUEST;
+ nl->nlmsg_pid = 0;
+ nl->nlmsg_seq = 0;
+ nl->nlmsg_len = NLMSG_LENGTH(sizeof(*rtm));
+ if (cmd == SIOCDELRT) {
+ nl->nlmsg_type = RTM_DELROUTE;
+ nl->nlmsg_flags = 0;
+ } else {
+ nl->nlmsg_type = RTM_NEWROUTE;
+ nl->nlmsg_flags = NLM_F_REQUEST|NLM_F_CREATE;
+ rtm->rtm_protocol = RTPROT_BOOT;
+ }
+
+ rtm->rtm_dst_len = plen;
+ rta->rta_dst = ptr;
+
+ if (r->rt_metric) {
+ *(u32*)&r->rt_pad3 = r->rt_metric - 1;
+ rta->rta_priority = (u32*)&r->rt_pad3;
+ }
+ if (r->rt_flags&RTF_REJECT) {
+ rtm->rtm_scope = RT_SCOPE_HOST;
+ rtm->rtm_type = RTN_UNREACHABLE;
+ return 0;
+ }
+ rtm->rtm_scope = RT_SCOPE_NOWHERE;
+ rtm->rtm_type = RTN_UNICAST;
+
+ if (r->rt_dev) {
+#ifdef CONFIG_IP_ALIAS
+ char *colon;
+#endif
+ struct device *dev;
+ char devname[IFNAMSIZ];
+
+ if (copy_from_user(devname, r->rt_dev, IFNAMSIZ-1))
+ return -EFAULT;
+ devname[IFNAMSIZ-1] = 0;
+#ifdef CONFIG_IP_ALIAS
+ colon = strchr(devname, ':');
+ if (colon)
+ *colon = 0;
+#endif
+ dev = dev_get(devname);
+ if (!dev)
+ return -ENODEV;
+ rta->rta_oif = &dev->ifindex;
+#ifdef CONFIG_IP_ALIAS
+ if (colon) {
+ struct in_ifaddr *ifa;
+ struct in_device *in_dev = dev->ip_ptr;
+ if (!in_dev)
+ return -ENODEV;
+ *colon = ':';
+ for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next)
+ if (strcmp(ifa->ifa_label, devname) == 0)
+ break;
+ if (ifa == NULL)
+ return -ENODEV;
+ rta->rta_prefsrc = &ifa->ifa_local;
+ }
+#endif
+ }
+
+ ptr = &((struct sockaddr_in*)&r->rt_gateway)->sin_addr.s_addr;
+ if (r->rt_gateway.sa_family == AF_INET && *ptr) {
+ rta->rta_gw = ptr;
+ if (r->rt_flags&RTF_GATEWAY && inet_addr_type(*ptr) == RTN_UNICAST)
+ rtm->rtm_scope = RT_SCOPE_UNIVERSE;
+ }
+
+ if (cmd == SIOCDELRT)
+ return 0;
+
+ if (r->rt_flags&RTF_GATEWAY && rta->rta_gw == NULL)
+ return -EINVAL;
+
+ if (rtm->rtm_scope == RT_SCOPE_NOWHERE)
+ rtm->rtm_scope = RT_SCOPE_LINK;
+
+ if (r->rt_flags&(RTF_MTU|RTF_WINDOW|RTF_IRTT)) {
+ struct rtattr *rec;
+ struct rtattr *mx = kmalloc(RTA_LENGTH(3*RTA_LENGTH(4)), GFP_KERNEL);
+ if (mx == NULL)
+ return -ENOMEM;
+ rta->rta_mx = mx;
+ mx->rta_type = RTA_METRICS;
+ mx->rta_len = RTA_LENGTH(0);
+ if (r->rt_flags&RTF_MTU) {
+ rec = (void*)((char*)mx + RTA_ALIGN(mx->rta_len));
+ rec->rta_type = RTAX_MTU;
+ rec->rta_len = RTA_LENGTH(4);
+ mx->rta_len += RTA_LENGTH(4);
+ *(u32*)RTA_DATA(rec) = r->rt_mtu;
+ }
+ if (r->rt_flags&RTF_WINDOW) {
+ rec = (void*)((char*)mx + RTA_ALIGN(mx->rta_len));
+ rec->rta_type = RTAX_WINDOW;
+ rec->rta_len = RTA_LENGTH(4);
+ mx->rta_len += RTA_LENGTH(4);
+ *(u32*)RTA_DATA(rec) = r->rt_window;
+ }
+ if (r->rt_flags&RTF_IRTT) {
+ rec = (void*)((char*)mx + RTA_ALIGN(mx->rta_len));
+ rec->rta_type = RTAX_RTT;
+ rec->rta_len = RTA_LENGTH(4);
+ mx->rta_len += RTA_LENGTH(4);
+ *(u32*)RTA_DATA(rec) = r->rt_irtt;
+ }
+ }
+ return 0;
+}
+
+#endif
+
+/*
+ Update FIB if:
+ - local address disappeared -> we must delete all the entries
+ referring to it.
+ - device went down -> we must shutdown all nexthops going via it.
+ */
+
+int fib_sync_down(u32 local, struct device *dev, int force)
+{
+ int ret = 0;
+ int scope = RT_SCOPE_NOWHERE;
+
+ if (force)
+ scope = -1;
+
+ for_fib_info() {
+ if (local && fi->fib_prefsrc == local) {
+ fi->fib_flags |= RTNH_F_DEAD;
+ ret++;
+ } else if (dev && fi->fib_nhs) {
+ int dead = 0;
+
+ change_nexthops(fi) {
+ if (nh->nh_flags&RTNH_F_DEAD)
+ dead++;
+ else if (nh->nh_dev == dev &&
+ nh->nh_scope != scope) {
+ nh->nh_flags |= RTNH_F_DEAD;
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ fi->fib_power -= nh->nh_power;
+ nh->nh_power = 0;
+#endif
+ dead++;
+ }
+ } endfor_nexthops(fi)
+ if (dead == fi->fib_nhs) {
+ fi->fib_flags |= RTNH_F_DEAD;
+ ret++;
+ }
+ }
+ } endfor_fib_info();
+ return ret;
+}
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+
+/*
+ Dead device goes up. We wake up dead nexthops.
+ It takes sense only on multipath routes.
+ */
+
+int fib_sync_up(struct device *dev)
+{
+ int ret = 0;
+
+ if (!(dev->flags&IFF_UP))
+ return 0;
+
+ for_fib_info() {
+ int alive = 0;
+
+ change_nexthops(fi) {
+ if (!(nh->nh_flags&RTNH_F_DEAD)) {
+ alive++;
+ continue;
+ }
+ if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
+ continue;
+ if (nh->nh_dev != dev || dev->ip_ptr == NULL)
+ continue;
+ alive++;
+ nh->nh_power = 0;
+ nh->nh_flags &= ~RTNH_F_DEAD;
+ } endfor_nexthops(fi)
+
+ if (alive == fi->fib_nhs) {
+ fi->fib_flags &= ~RTNH_F_DEAD;
+ ret++;
+ }
+ } endfor_fib_info();
+ return ret;
+}
+
+/*
+ The algorithm is suboptimal, but it provides really
+ fair weighted route distribution.
+ */
+
+void fib_select_multipath(const struct rt_key *key, struct fib_result *res)
+{
+ struct fib_info *fi = res->fi;
+ int w;
+
+ if (fi->fib_power <= 0) {
+ int power = 0;
+ change_nexthops(fi) {
+ if (!(nh->nh_flags&RTNH_F_DEAD)) {
+ power += nh->nh_weight;
+ nh->nh_power = nh->nh_weight;
+ }
+ } endfor_nexthops(fi);
+ fi->fib_power = power;
+#if 1
+ if (power <= 0) {
+ printk(KERN_CRIT "impossible 777\n");
+ return;
+ }
+#endif
+ }
+
+
+ /* w should be random number [0..fi->fib_power-1],
+ it is pretty bad approximation.
+ */
+
+ w = jiffies % fi->fib_power;
+
+ change_nexthops(fi) {
+ if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
+ if ((w -= nh->nh_power) <= 0) {
+ nh->nh_power--;
+ fi->fib_power--;
+ res->nh_sel = nhsel;
+ return;
+ }
+ }
+ } endfor_nexthops(fi);
+
+#if 1
+ printk(KERN_CRIT "impossible 888\n");
+#endif
+ return;
+}
+#endif
+
+
+#ifdef CONFIG_PROC_FS
+
+static unsigned fib_flag_trans(int type, int dead, u32 mask, struct fib_info *fi)
+{
+ static unsigned type2flags[RTN_MAX+1] = {
+ 0, 0, 0, 0, 0, 0, 0, RTF_REJECT, RTF_REJECT, 0, 0, 0
+ };
+ unsigned flags = type2flags[type];
+
+ if (fi && fi->fib_nh->nh_gw)
+ flags |= RTF_GATEWAY;
+ if (mask == 0xFFFFFFFF)
+ flags |= RTF_HOST;
+ if (!dead)
+ flags |= RTF_UP;
+ return flags;
+}
+
+void fib_node_get_info(int type, int dead, struct fib_info *fi, u32 prefix, u32 mask, char *buffer)
+{
+ int len;
+ unsigned flags = fib_flag_trans(type, dead, mask, fi);
+
+ if (fi) {
+ len = sprintf(buffer, "%s\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
+ fi->fib_dev ? fi->fib_dev->name : "*", prefix,
+ fi->fib_nh->nh_gw, flags, 0, 0, fi->fib_priority,
+ mask, fi->fib_mtu, fi->fib_window, fi->fib_rtt);
+ } else {
+ len = sprintf(buffer, "*\t%08X\t%08X\t%04X\t%d\t%u\t%d\t%08X\t%d\t%u\t%u",
+ prefix, 0,
+ flags, 0, 0, 0,
+ mask, 0, 0, 0);
+ }
+ memset(buffer+len, ' ', 127-len);
+ buffer[127] = '\n';
+}
+
+#endif