diff options
Diffstat (limited to 'net/ipv4/fib_semantics.c')
-rw-r--r-- | net/ipv4/fib_semantics.c | 257 |
1 files changed, 135 insertions, 122 deletions
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 20f09c5b31e8..ba52f399a898 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -60,21 +60,30 @@ static struct hlist_head fib_info_devhash[DEVINDEX_HASHSIZE]; static DEFINE_SPINLOCK(fib_multipath_lock); -#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 *nexthop_nh; \ -for (nhsel=0, nexthop_nh = (struct fib_nh *)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nexthop_nh++, nhsel++) +#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 *nexthop_nh; \ + for (nhsel = 0, nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \ + nhsel < (fi)->fib_nhs; \ + nexthop_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 for_nexthops(fi) { \ + int nhsel; const struct fib_nh *nh = (fi)->fib_nh; \ + for (nhsel = 0; nhsel < 1; nhsel++) -#define change_nexthops(fi) { int nhsel = 0; struct fib_nh *nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \ -for (nhsel=0; nhsel < 1; nhsel++) +#define change_nexthops(fi) { \ + int nhsel; \ + struct fib_nh *nexthop_nh = (struct fib_nh *)((fi)->fib_nh); \ + for (nhsel = 0; nhsel < 1; nhsel++) #endif /* CONFIG_IP_ROUTE_MULTIPATH */ @@ -86,54 +95,54 @@ static const struct int error; u8 scope; } fib_props[RTN_MAX + 1] = { - { + [RTN_UNSPEC] = { .error = 0, .scope = RT_SCOPE_NOWHERE, - }, /* RTN_UNSPEC */ - { + }, + [RTN_UNICAST] = { .error = 0, .scope = RT_SCOPE_UNIVERSE, - }, /* RTN_UNICAST */ - { + }, + [RTN_LOCAL] = { .error = 0, .scope = RT_SCOPE_HOST, - }, /* RTN_LOCAL */ - { + }, + [RTN_BROADCAST] = { .error = 0, .scope = RT_SCOPE_LINK, - }, /* RTN_BROADCAST */ - { + }, + [RTN_ANYCAST] = { .error = 0, .scope = RT_SCOPE_LINK, - }, /* RTN_ANYCAST */ - { + }, + [RTN_MULTICAST] = { .error = 0, .scope = RT_SCOPE_UNIVERSE, - }, /* RTN_MULTICAST */ - { + }, + [RTN_BLACKHOLE] = { .error = -EINVAL, .scope = RT_SCOPE_UNIVERSE, - }, /* RTN_BLACKHOLE */ - { + }, + [RTN_UNREACHABLE] = { .error = -EHOSTUNREACH, .scope = RT_SCOPE_UNIVERSE, - }, /* RTN_UNREACHABLE */ - { + }, + [RTN_PROHIBIT] = { .error = -EACCES, .scope = RT_SCOPE_UNIVERSE, - }, /* RTN_PROHIBIT */ - { + }, + [RTN_THROW] = { .error = -EAGAIN, .scope = RT_SCOPE_UNIVERSE, - }, /* RTN_THROW */ - { + }, + [RTN_NAT] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE, - }, /* RTN_NAT */ - { + }, + [RTN_XRESOLVE] = { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE, - }, /* RTN_XRESOLVE */ + }, }; @@ -142,7 +151,7 @@ static const struct void free_fib_info(struct fib_info *fi) { if (fi->fib_dead == 0) { - printk(KERN_WARNING "Freeing alive fib_info %p\n", fi); + pr_warning("Freeing alive fib_info %p\n", fi); return; } change_nexthops(fi) { @@ -173,7 +182,7 @@ void fib_release_info(struct fib_info *fi) spin_unlock_bh(&fib_info_lock); } -static __inline__ int nh_comp(const struct fib_info *fi, const struct fib_info *ofi) +static inline int nh_comp(const struct fib_info *fi, const struct fib_info *ofi) { const struct fib_nh *onh = ofi->fib_nh; @@ -187,7 +196,7 @@ static __inline__ int nh_comp(const struct fib_info *fi, const struct fib_info * #ifdef CONFIG_NET_CLS_ROUTE nh->nh_tclassid != onh->nh_tclassid || #endif - ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD)) + ((nh->nh_flags ^ onh->nh_flags) & ~RTNH_F_DEAD)) return -1; onh++; } endfor_nexthops(fi); @@ -238,7 +247,7 @@ static struct fib_info *fib_find_info(const struct fib_info *nfi) nfi->fib_priority == fi->fib_priority && memcmp(nfi->fib_metrics, fi->fib_metrics, sizeof(fi->fib_metrics)) == 0 && - ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 && + ((nfi->fib_flags ^ fi->fib_flags) & ~RTNH_F_DEAD) == 0 && (nfi->fib_nhs == 0 || nh_comp(fi, nfi) == 0)) return fi; } @@ -247,9 +256,8 @@ static struct fib_info *fib_find_info(const struct fib_info *nfi) } /* Check, that the gateway is already configured. - Used only by redirect accept routine. + * Used only by redirect accept routine. */ - int ip_fib_check_default(__be32 gw, struct net_device *dev) { struct hlist_head *head; @@ -264,7 +272,7 @@ int ip_fib_check_default(__be32 gw, struct net_device *dev) hlist_for_each_entry(nh, node, head, nh_hash) { if (nh->nh_dev == dev && nh->nh_gw == gw && - !(nh->nh_flags&RTNH_F_DEAD)) { + !(nh->nh_flags & RTNH_F_DEAD)) { spin_unlock(&fib_info_lock); return 0; } @@ -362,10 +370,10 @@ int fib_detect_death(struct fib_info *fi, int order, } if (state == NUD_REACHABLE) return 0; - if ((state&NUD_VALID) && order != dflt) + if ((state & NUD_VALID) && order != dflt) return 0; - if ((state&NUD_VALID) || - (*last_idx<0 && order > dflt)) { + if ((state & NUD_VALID) || + (*last_idx < 0 && order > dflt)) { *last_resort = fi; *last_idx = order; } @@ -476,69 +484,69 @@ int fib_nh_match(struct fib_config *cfg, struct fib_info *fi) /* - 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 chose 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) + * 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 chose 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(struct fib_config *cfg, struct fib_info *fi, struct fib_nh *nh) { int err; struct net *net; + struct net_device *dev; net = cfg->fc_nlinfo.nl_net; if (nh->nh_gw) { struct fib_result res; - if (nh->nh_flags&RTNH_F_ONLINK) { - struct net_device *dev; + if (nh->nh_flags & RTNH_F_ONLINK) { if (cfg->fc_scope >= RT_SCOPE_LINK) return -EINVAL; if (inet_addr_type(net, nh->nh_gw) != RTN_UNICAST) return -EINVAL; - if ((dev = __dev_get_by_index(net, nh->nh_oif)) == NULL) + dev = __dev_get_by_index(net, nh->nh_oif); + if (!dev) return -ENODEV; - if (!(dev->flags&IFF_UP)) + if (!(dev->flags & IFF_UP)) return -ENETDOWN; nh->nh_dev = dev; dev_hold(dev); @@ -559,7 +567,8 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi, /* It is not necessary, but requires a bit of thinking */ if (fl.fl4_scope < RT_SCOPE_LINK) fl.fl4_scope = RT_SCOPE_LINK; - if ((err = fib_lookup(net, &fl, &res)) != 0) + err = fib_lookup(net, &fl, &res); + if (err) return err; } err = -EINVAL; @@ -567,11 +576,12 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi, goto out; nh->nh_scope = res.scope; nh->nh_oif = FIB_RES_OIF(res); - if ((nh->nh_dev = FIB_RES_DEV(res)) == NULL) + nh->nh_dev = dev = FIB_RES_DEV(res); + if (!dev) goto out; - dev_hold(nh->nh_dev); + dev_hold(dev); err = -ENETDOWN; - if (!(nh->nh_dev->flags & IFF_UP)) + if (!(dev->flags & IFF_UP)) goto out; err = 0; out: @@ -580,13 +590,13 @@ out: } else { struct in_device *in_dev; - if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK)) + if (nh->nh_flags & (RTNH_F_PERVASIVE | RTNH_F_ONLINK)) return -EINVAL; in_dev = inetdev_by_index(net, nh->nh_oif); if (in_dev == NULL) return -ENODEV; - if (!(in_dev->dev->flags&IFF_UP)) { + if (!(in_dev->dev->flags & IFF_UP)) { in_dev_put(in_dev); return -ENETDOWN; } @@ -602,7 +612,9 @@ static inline unsigned int fib_laddr_hashfn(__be32 val) { unsigned int mask = (fib_hash_size - 1); - return ((__force u32)val ^ ((__force u32)val >> 7) ^ ((__force u32)val >> 14)) & mask; + return ((__force u32)val ^ + ((__force u32)val >> 7) ^ + ((__force u32)val >> 14)) & mask; } static struct hlist_head *fib_hash_alloc(int bytes) @@ -611,7 +623,8 @@ static struct hlist_head *fib_hash_alloc(int bytes) return kzalloc(bytes, GFP_KERNEL); else return (struct hlist_head *) - __get_free_pages(GFP_KERNEL | __GFP_ZERO, get_order(bytes)); + __get_free_pages(GFP_KERNEL | __GFP_ZERO, + get_order(bytes)); } static void fib_hash_free(struct hlist_head *hash, int bytes) @@ -806,7 +819,8 @@ struct fib_info *fib_create_info(struct fib_config *cfg) goto failure; } else { change_nexthops(fi) { - if ((err = fib_check_nh(cfg, fi, nexthop_nh)) != 0) + err = fib_check_nh(cfg, fi, nexthop_nh); + if (err != 0) goto failure; } endfor_nexthops(fi) } @@ -819,7 +833,8 @@ struct fib_info *fib_create_info(struct fib_config *cfg) } link_it: - if ((ofi = fib_find_info(fi)) != NULL) { + ofi = fib_find_info(fi); + if (ofi) { fi->fib_dead = 1; free_fib_info(fi); ofi->fib_treeref++; @@ -895,7 +910,7 @@ int fib_semantic_match(struct list_head *head, const struct flowi *flp, case RTN_ANYCAST: case RTN_MULTICAST: for_nexthops(fi) { - if (nh->nh_flags&RTNH_F_DEAD) + if (nh->nh_flags & RTNH_F_DEAD) continue; if (!flp->oif || flp->oif == nh->nh_oif) break; @@ -906,16 +921,15 @@ int fib_semantic_match(struct list_head *head, const struct flowi *flp, goto out_fill_res; } #else - if (nhsel < 1) { + if (nhsel < 1) goto out_fill_res; - } #endif endfor_nexthops(fi); continue; default: - printk(KERN_WARNING "fib_semantic_match bad type %#x\n", - fa->fa_type); + pr_warning("fib_semantic_match bad type %#x\n", + fa->fa_type); return -EINVAL; } } @@ -1028,10 +1042,10 @@ nla_put_failure: } /* - 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. + * 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_addr(struct net *net, __be32 local) { @@ -1078,7 +1092,7 @@ int fib_sync_down_dev(struct net_device *dev, int force) prev_fi = fi; dead = 0; change_nexthops(fi) { - if (nexthop_nh->nh_flags&RTNH_F_DEAD) + if (nexthop_nh->nh_flags & RTNH_F_DEAD) dead++; else if (nexthop_nh->nh_dev == dev && nexthop_nh->nh_scope != scope) { @@ -1110,10 +1124,9 @@ int fib_sync_down_dev(struct net_device *dev, int force) #ifdef CONFIG_IP_ROUTE_MULTIPATH /* - Dead device goes up. We wake up dead nexthops. - It takes sense only on multipath routes. + * Dead device goes up. We wake up dead nexthops. + * It takes sense only on multipath routes. */ - int fib_sync_up(struct net_device *dev) { struct fib_info *prev_fi; @@ -1123,7 +1136,7 @@ int fib_sync_up(struct net_device *dev) struct fib_nh *nh; int ret; - if (!(dev->flags&IFF_UP)) + if (!(dev->flags & IFF_UP)) return 0; prev_fi = NULL; @@ -1142,12 +1155,12 @@ int fib_sync_up(struct net_device *dev) prev_fi = fi; alive = 0; change_nexthops(fi) { - if (!(nexthop_nh->nh_flags&RTNH_F_DEAD)) { + if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) { alive++; continue; } if (nexthop_nh->nh_dev == NULL || - !(nexthop_nh->nh_dev->flags&IFF_UP)) + !(nexthop_nh->nh_dev->flags & IFF_UP)) continue; if (nexthop_nh->nh_dev != dev || !__in_dev_get_rtnl(dev)) @@ -1169,10 +1182,9 @@ int fib_sync_up(struct net_device *dev) } /* - The algorithm is suboptimal, but it provides really - fair weighted route distribution. + * The algorithm is suboptimal, but it provides really + * fair weighted route distribution. */ - void fib_select_multipath(const struct flowi *flp, struct fib_result *res) { struct fib_info *fi = res->fi; @@ -1182,7 +1194,7 @@ void fib_select_multipath(const struct flowi *flp, struct fib_result *res) if (fi->fib_power <= 0) { int power = 0; change_nexthops(fi) { - if (!(nexthop_nh->nh_flags&RTNH_F_DEAD)) { + if (!(nexthop_nh->nh_flags & RTNH_F_DEAD)) { power += nexthop_nh->nh_weight; nexthop_nh->nh_power = nexthop_nh->nh_weight; } @@ -1198,15 +1210,16 @@ void fib_select_multipath(const struct flowi *flp, struct fib_result *res) /* w should be random number [0..fi->fib_power-1], - it is pretty bad approximation. + * it is pretty bad approximation. */ w = jiffies % fi->fib_power; change_nexthops(fi) { - if (!(nexthop_nh->nh_flags&RTNH_F_DEAD) && + if (!(nexthop_nh->nh_flags & RTNH_F_DEAD) && nexthop_nh->nh_power) { - if ((w -= nexthop_nh->nh_power) <= 0) { + w -= nexthop_nh->nh_power; + if (w <= 0) { nexthop_nh->nh_power--; fi->fib_power--; res->nh_sel = nhsel; |