cregit-Linux how code gets into the kernel

Release 4.8 net/decnet/dn_fib.c

Directory: net/decnet
/*
 * DECnet       An implementation of the DECnet protocol suite for the LINUX
 *              operating system.  DECnet is implemented using the  BSD Socket
 *              interface as the means of communication with the user level.
 *
 *              DECnet Routing Forwarding Information Base (Glue/Info List)
 *
 * Author:      Steve Whitehouse <SteveW@ACM.org>
 *
 *
 * Changes:
 *              Alexey Kuznetsov : SMP locking changes
 *              Steve Whitehouse : Rewrote it... Well to be more correct, I
 *                                 copied most of it from the ipv4 fib code.
 *              Steve Whitehouse : Updated it in style and fixed a few bugs
 *                                 which were fixed in the ipv4 code since
 *                                 this code was copied from it.
 *
 */
#include <linux/string.h>
#include <linux/net.h>
#include <linux/socket.h>
#include <linux/slab.h>
#include <linux/sockios.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/proc_fs.h>
#include <linux/netdevice.h>
#include <linux/timer.h>
#include <linux/spinlock.h>
#include <linux/atomic.h>
#include <asm/uaccess.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/fib_rules.h>
#include <net/dn.h>
#include <net/dn_route.h>
#include <net/dn_fib.h>
#include <net/dn_neigh.h>
#include <net/dn_dev.h>
#include <net/nexthop.h>


#define RT_MIN_TABLE 1


#define for_fib_info() { struct dn_fib_info *fi;\
        for(fi = dn_fib_info_list; fi; fi = fi->fib_next)

#define endfor_fib_info() }


#define for_nexthops(fi) { int nhsel; const struct dn_fib_nh *nh;\
        for(nhsel = 0, nh = (fi)->fib_nh; nhsel < (fi)->fib_nhs; nh++, nhsel++)


#define change_nexthops(fi) { int nhsel; struct dn_fib_nh *nh;\
        for(nhsel = 0, nh = (struct dn_fib_nh *)((fi)->fib_nh); nhsel < (fi)->fib_nhs; nh++, nhsel++)


#define endfor_nexthops(fi) }

static DEFINE_SPINLOCK(dn_fib_multipath_lock);

static struct dn_fib_info *dn_fib_info_list;
static DEFINE_SPINLOCK(dn_fib_info_lock);

static struct
{
	
int error;
	
u8 scope;
} 
dn_fib_props[RTN_MAX+1] = {
	[RTN_UNSPEC] =      { .error = 0,       .scope = RT_SCOPE_NOWHERE },
	[RTN_UNICAST] =     { .error = 0,       .scope = RT_SCOPE_UNIVERSE },
	[RTN_LOCAL] =       { .error = 0,       .scope = RT_SCOPE_HOST },
	[RTN_BROADCAST] =   { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
	[RTN_ANYCAST] =     { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
	[RTN_MULTICAST] =   { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
	[RTN_BLACKHOLE] =   { .error = -EINVAL, .scope = RT_SCOPE_UNIVERSE },
	[RTN_UNREACHABLE] = { .error = -EHOSTUNREACH, .scope = RT_SCOPE_UNIVERSE },
	[RTN_PROHIBIT] =    { .error = -EACCES, .scope = RT_SCOPE_UNIVERSE },
	[RTN_THROW] =       { .error = -EAGAIN, .scope = RT_SCOPE_UNIVERSE },
	[RTN_NAT] =         { .error = 0,       .scope = RT_SCOPE_NOWHERE },
	[RTN_XRESOLVE] =    { .error = -EINVAL, .scope = RT_SCOPE_NOWHERE },
};

static int dn_fib_sync_down(__le16 local, struct net_device *dev, int force);
static int dn_fib_sync_up(struct net_device *dev);


void dn_fib_free_info(struct dn_fib_info *fi) { if (fi->fib_dead == 0) { printk(KERN_DEBUG "DECnet: BUG! Attempt to free alive dn_fib_info\n"); return; } change_nexthops(fi) { if (nh->nh_dev) dev_put(nh->nh_dev); nh->nh_dev = NULL; } endfor_nexthops(fi); kfree(fi); }

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void dn_fib_release_info(struct dn_fib_info *fi) { spin_lock(&dn_fib_info_lock); if (fi && --fi->fib_treeref == 0) { 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 == dn_fib_info_list) dn_fib_info_list = fi->fib_next; fi->fib_dead = 1; dn_fib_info_put(fi); } spin_unlock(&dn_fib_info_lock); }

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static inline int dn_fib_nh_comp(const struct dn_fib_info *fi, const struct dn_fib_info *ofi) { const struct dn_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 || nh->nh_weight != onh->nh_weight || ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD)) return -1; onh++; } endfor_nexthops(fi); return 0; }

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static inline struct dn_fib_info *dn_fib_find_info(const struct dn_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 && memcmp(nfi->fib_metrics, fi->fib_metrics, sizeof(fi->fib_metrics)) == 0 && ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 && (nfi->fib_nhs == 0 || dn_fib_nh_comp(fi, nfi) == 0)) return fi; } endfor_fib_info(); return NULL; }

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Total119100.00%3100.00%


static int dn_fib_count_nhs(const struct nlattr *attr) { struct rtnexthop *nhp = nla_data(attr); int nhs = 0, nhlen = nla_len(attr); while (rtnh_ok(nhp, nhlen)) { nhs++; nhp = rtnh_next(nhp, &nhlen); } /* leftover implies invalid nexthop configuration, discard it */ return nhlen > 0 ? 0 : nhs; }

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thomas grafthomas graf1116.18%125.00%
Total68100.00%4100.00%


static int dn_fib_get_nhs(struct dn_fib_info *fi, const struct nlattr *attr, const struct rtmsg *r) { struct rtnexthop *nhp = nla_data(attr); int nhlen = nla_len(attr); change_nexthops(fi) { int attrlen; if (!rtnh_ok(nhp, nhlen)) 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; attrlen = rtnh_attrlen(nhp); if (attrlen > 0) { struct nlattr *gw_attr; gw_attr = nla_find((struct nlattr *) (nhp + 1), attrlen, RTA_GATEWAY); nh->nh_gw = gw_attr ? nla_get_le16(gw_attr) : 0; } nhp = rtnh_next(nhp, &nhlen); } endfor_nexthops(fi); return 0; }

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Total170100.00%4100.00%


static int dn_fib_check_nh(const struct rtmsg *r, struct dn_fib_info *fi, struct dn_fib_nh *nh) { int err; if (nh->nh_gw) { struct flowidn fld; struct dn_fib_res res; if (nh->nh_flags&RTNH_F_ONLINK) { struct net_device *dev; if (r->rtm_scope >= RT_SCOPE_LINK) return -EINVAL; if (dnet_addr_type(nh->nh_gw) != RTN_UNICAST) return -EINVAL; if ((dev = __dev_get_by_index(&init_net, nh->nh_oif)) == NULL) return -ENODEV; if (!(dev->flags&IFF_UP)) return -ENETDOWN; nh->nh_dev = dev; dev_hold(dev); nh->nh_scope = RT_SCOPE_LINK; return 0; } memset(&fld, 0, sizeof(fld)); fld.daddr = nh->nh_gw; fld.flowidn_oif = nh->nh_oif; fld.flowidn_scope = r->rtm_scope + 1; if (fld.flowidn_scope < RT_SCOPE_LINK) fld.flowidn_scope = RT_SCOPE_LINK; if ((err = dn_fib_lookup(&fld, &res)) != 0) return err; err = -EINVAL; if (res.type != RTN_UNICAST && res.type != RTN_LOCAL) goto out; nh->nh_scope = res.scope; nh->nh_oif = DN_FIB_RES_OIF(res); nh->nh_dev = DN_FIB_RES_DEV(res); if (nh->nh_dev == NULL) goto out; dev_hold(nh->nh_dev); err = -ENETDOWN; if (!(nh->nh_dev->flags & IFF_UP)) goto out; err = 0; out: dn_fib_res_put(&res); return err; } else { struct net_device *dev; if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK)) return -EINVAL; dev = __dev_get_by_index(&init_net, nh->nh_oif); if (dev == NULL || dev->dn_ptr == NULL) return -ENODEV; if (!(dev->flags&IFF_UP)) return -ENETDOWN; nh->nh_dev = dev; dev_hold(nh->nh_dev); nh->nh_scope = RT_SCOPE_HOST; } return 0; }

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david s. millerdavid s. miller153.71%116.67%
eric w. biedermaneric w. biederman61.49%116.67%
stephen hemmingerstephen hemminger30.74%116.67%
Total404100.00%6100.00%


struct dn_fib_info *dn_fib_create_info(const struct rtmsg *r, struct nlattr *attrs[], const struct nlmsghdr *nlh, int *errp) { int err; struct dn_fib_info *fi = NULL; struct dn_fib_info *ofi; int nhs = 1; if (r->rtm_type > RTN_MAX) goto err_inval; if (dn_fib_props[r->rtm_type].scope > r->rtm_scope) goto err_inval; if (attrs[RTA_MULTIPATH] && (nhs = dn_fib_count_nhs(attrs[RTA_MULTIPATH])) == 0) goto err_inval; fi = kzalloc(sizeof(*fi)+nhs*sizeof(struct dn_fib_nh), GFP_KERNEL); err = -ENOBUFS; if (fi == NULL) goto failure; fi->fib_protocol = r->rtm_protocol; fi->fib_nhs = nhs; fi->fib_flags = r->rtm_flags; if (attrs[RTA_PRIORITY]) fi->fib_priority = nla_get_u32(attrs[RTA_PRIORITY]); if (attrs[RTA_METRICS]) { struct nlattr *attr; int rem; nla_for_each_nested(attr, attrs[RTA_METRICS], rem) { int type = nla_type(attr); if (type) { if (type > RTAX_MAX || type == RTAX_CC_ALGO || nla_len(attr) < 4) goto err_inval; fi->fib_metrics[type-1] = nla_get_u32(attr); } } } if (attrs[RTA_PREFSRC]) fi->fib_prefsrc = nla_get_le16(attrs[RTA_PREFSRC]); if (attrs[RTA_MULTIPATH]) { if ((err = dn_fib_get_nhs(fi, attrs[RTA_MULTIPATH], r)) != 0) goto failure; if (attrs[RTA_OIF] && fi->fib_nh->nh_oif != nla_get_u32(attrs[RTA_OIF])) goto err_inval; if (attrs[RTA_GATEWAY] && fi->fib_nh->nh_gw != nla_get_le16(attrs[RTA_GATEWAY])) goto err_inval; } else { struct dn_fib_nh *nh = fi->fib_nh; if (attrs[RTA_OIF]) nh->nh_oif = nla_get_u32(attrs[RTA_OIF]); if (attrs[RTA_GATEWAY]) nh->nh_gw = nla_get_le16(attrs[RTA_GATEWAY]); nh->nh_flags = r->rtm_flags; nh->nh_weight = 1; } if (r->rtm_type == RTN_NAT) { if (!attrs[RTA_GATEWAY] || nhs != 1 || attrs[RTA_OIF]) goto err_inval; fi->fib_nh->nh_gw = nla_get_le16(attrs[RTA_GATEWAY]); goto link_it; } if (dn_fib_props[r->rtm_type].error) { if (attrs[RTA_GATEWAY] || attrs[RTA_OIF] || attrs[RTA_MULTIPATH]) goto err_inval; goto link_it; } if (r->rtm_scope > RT_SCOPE_HOST) goto err_inval; if (r->rtm_scope == RT_SCOPE_HOST) { struct dn_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(&init_net, fi->fib_nh->nh_oif); err = -ENODEV; if (nh->nh_dev == NULL) goto failure; } else { change_nexthops(fi) { if ((err = dn_fib_check_nh(r, fi, nh)) != 0) goto failure; } endfor_nexthops(fi) } if (fi->fib_prefsrc) { if (r->rtm_type != RTN_LOCAL || !attrs[RTA_DST] || fi->fib_prefsrc != nla_get_le16(attrs[RTA_DST])) if (dnet_addr_type(fi->fib_prefsrc) != RTN_LOCAL) goto err_inval; } link_it: if ((ofi = dn_fib_find_info(fi)) != NULL) { fi->fib_dead = 1; dn_fib_free_info(fi); ofi->fib_treeref++; return ofi; } fi->fib_treeref++; atomic_inc(&fi->fib_clntref); spin_lock(&dn_fib_info_lock); fi->fib_next = dn_fib_info_list; fi->fib_prev = NULL; if (dn_fib_info_list) dn_fib_info_list->fib_prev = fi; dn_fib_info_list = fi; spin_unlock(&dn_fib_info_lock); return fi; err_inval: err = -EINVAL; failure: *errp = err; if (fi) { fi->fib_dead = 1; dn_fib_free_info(fi); } return NULL; }

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pre-gitpre-git52066.16%220.00%
thomas grafthomas graf16721.25%220.00%
steven whitehousesteven whitehouse9011.45%220.00%
daniel borkmanndaniel borkmann40.51%110.00%
eric w. biedermaneric w. biederman30.38%110.00%
eric dumazeteric dumazet10.13%110.00%
panagiotis issaris*panagiotis issaris*10.13%110.00%
Total786100.00%10100.00%


int dn_fib_semantic_match(int type, struct dn_fib_info *fi, const struct flowidn *fld, struct dn_fib_res *res) { int err = dn_fib_props[type].error; if (err == 0) { if (fi->fib_flags & RTNH_F_DEAD) return 1; res->fi = fi; switch (type) { case RTN_NAT: DN_FIB_RES_RESET(*res); atomic_inc(&fi->fib_clntref); return 0; case RTN_UNICAST: case RTN_LOCAL: for_nexthops(fi) { if (nh->nh_flags & RTNH_F_DEAD) continue; if (!fld->flowidn_oif || fld->flowidn_oif == nh->nh_oif) break; } if (nhsel < fi->fib_nhs) { res->nh_sel = nhsel; atomic_inc(&fi->fib_clntref); return 0; } endfor_nexthops(fi); res->fi = NULL; return 1; default: net_err_ratelimited("DECnet: impossible routing event : dn_fib_semantic_match type=%d\n", type); res->fi = NULL; return -EINVAL; } } return err; }

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david s. millerdavid s. miller63.26%120.00%
joe perchesjoe perches10.54%120.00%
Total184100.00%5100.00%


void dn_fib_select_multipath(const struct flowidn *fld, struct dn_fib_res *res) { struct dn_fib_info *fi = res->fi; int w; spin_lock_bh(&dn_fib_multipath_lock); 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 (power < 0) { spin_unlock_bh(&dn_fib_multipath_lock); res->nh_sel = 0; return; } } 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; spin_unlock_bh(&dn_fib_multipath_lock); return; } } } endfor_nexthops(fi); res->nh_sel = 0; spin_unlock_bh(&dn_fib_multipath_lock); }

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Total199100.00%4100.00%


static inline u32 rtm_get_table(struct nlattr *attrs[], u8 table) { if (attrs[RTA_TABLE]) table = nla_get_u32(attrs[RTA_TABLE]); return table; }

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static int dn_fib_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh) { struct net *net = sock_net(skb->sk); struct dn_fib_table *tb; struct rtmsg *r = nlmsg_data(nlh); struct nlattr *attrs[RTA_MAX+1]; int err; if (!netlink_capable(skb, CAP_NET_ADMIN)) return -EPERM; if (!net_eq(net, &init_net)) return -EINVAL; err = nlmsg_parse(nlh, sizeof(*r), attrs, RTA_MAX, rtm_dn_policy); if (err < 0) return err; tb = dn_fib_get_table(rtm_get_table(attrs, r->rtm_table), 0); if (!tb) return -ESRCH; return tb->delete(tb, r, attrs, nlh, &NETLINK_CB(skb)); }

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denis v. lunevdenis v. lunev1710.76%110.00%
eric w. biedermaneric w. biederman148.86%220.00%
octavian purdilaoctavian purdila53.16%110.00%
patrick mchardypatrick mchardy42.53%110.00%
hideaki yoshifujihideaki yoshifuji31.90%110.00%
Total158100.00%10100.00%


static int dn_fib_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh) { struct net *net = sock_net(skb->sk); struct dn_fib_table *tb; struct rtmsg *r = nlmsg_data(nlh); struct nlattr *attrs[RTA_MAX+1]; int err; if (!netlink_capable(skb, CAP_NET_ADMIN)) return -EPERM; if (!net_eq(net, &init_net)) return -EINVAL; err = nlmsg_parse(nlh, sizeof(*r), attrs, RTA_MAX, rtm_dn_policy); if (err < 0) return err; tb = dn_fib_get_table(rtm_get_table(attrs, r->rtm_table), 1); if (!tb) return -ENOBUFS; return tb->insert(tb, r, attrs, nlh, &NETLINK_CB(skb)); }

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denis v. lunevdenis v. lunev1710.76%110.00%
eric w. biedermaneric w. biederman148.86%220.00%
octavian purdilaoctavian purdila53.16%110.00%
patrick mchardypatrick mchardy42.53%110.00%
hideaki yoshifujihideaki yoshifuji31.90%110.00%
Total158100.00%10100.00%


static void fib_magic(int cmd, int type, __le16 dst, int dst_len, struct dn_ifaddr *ifa) { struct dn_fib_table *tb; struct { struct nlmsghdr nlh; struct rtmsg rtm; } req; struct { struct nlattr hdr; __le16 dst; } dst_attr = { .dst = dst, }; struct { struct nlattr hdr; __le16 prefsrc; } prefsrc_attr = { .prefsrc = ifa->ifa_local, }; struct { struct nlattr hdr; u32 oif; } oif_attr = { .oif = ifa->ifa_dev->dev->ifindex, }; struct nlattr *attrs[RTA_MAX+1] = { [RTA_DST] = (struct nlattr *) &dst_attr, [RTA_PREFSRC] = (struct nlattr * ) &prefsrc_attr, [RTA_OIF] = (struct nlattr *) &oif_attr, }; memset(&req.rtm, 0, sizeof(req.rtm)); if (type == RTN_UNICAST) tb = dn_fib_get_table(RT_MIN_TABLE, 1); else tb = dn_fib_get_table(RT_TABLE_LOCAL, 1); if (tb == NULL) return; req.nlh.nlmsg_len = sizeof(req); req.nlh.nlmsg_type = cmd; req.nlh.nlmsg_flags = NLM_F_REQUEST|