cregit-Linux how code gets into the kernel

Release 4.8 net/ipv6/addrlabel.c

Directory: net/ipv6
/*
 * IPv6 Address Label subsystem
 * for the IPv6 "Default" Source Address Selection
 *
 * Copyright (C)2007 USAGI/WIDE Project
 */
/*
 * Author:
 *      YOSHIFUJI Hideaki @ USAGI/WIDE Project <yoshfuji@linux-ipv6.org>
 */

#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/rcupdate.h>
#include <linux/in6.h>
#include <linux/slab.h>
#include <net/addrconf.h>
#include <linux/if_addrlabel.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>

#if 0
#define ADDRLABEL(x...) printk(x)
#else

#define ADDRLABEL(x...) do { ; } while (0)
#endif

/*
 * Policy Table
 */

struct ip6addrlbl_entry {
	
possible_net_t lbl_net;
	
struct in6_addr prefix;
	
int prefixlen;
	
int ifindex;
	
int addrtype;
	
u32 label;
	
struct hlist_node list;
	
atomic_t refcnt;
	
struct rcu_head rcu;
};


static struct ip6addrlbl_table
{
	
struct hlist_head head;
	
spinlock_t lock;
	
u32 seq;
} 
ip6addrlbl_table;


static inline struct net *ip6addrlbl_net(const struct ip6addrlbl_entry *lbl) { return read_pnet(&lbl->lbl_net); }

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benjamin therybenjamin thery2083.33%150.00%
eric dumazeteric dumazet416.67%150.00%
Total24100.00%2100.00%

/* * Default policy table (RFC6724 + extensions) * * prefix addr_type label * ------------------------------------------------------------------------- * ::1/128 LOOPBACK 0 * ::/0 N/A 1 * 2002::/16 N/A 2 * ::/96 COMPATv4 3 * ::ffff:0:0/96 V4MAPPED 4 * fc00::/7 N/A 5 ULA (RFC 4193) * 2001::/32 N/A 6 Teredo (RFC 4380) * 2001:10::/28 N/A 7 ORCHID (RFC 4843) * fec0::/10 N/A 11 Site-local * (deprecated by RFC3879) * 3ffe::/16 N/A 12 6bone * * Note: 0xffffffff is used if we do not have any policies. * Note: Labels for ULA and 6to4 are different from labels listed in RFC6724. */ #define IPV6_ADDR_LABEL_DEFAULT 0xffffffffUL static const __net_initconst struct ip6addrlbl_init_table { const struct in6_addr *prefix; int prefixlen; u32 label; } ip6addrlbl_init_table[] = { { /* ::/0 */ .prefix = &in6addr_any, .label = 1, }, { /* fc00::/7 */ .prefix = &(struct in6_addr){ { { 0xfc } } } , .prefixlen = 7, .label = 5, }, { /* fec0::/10 */ .prefix = &(struct in6_addr){ { { 0xfe, 0xc0 } } }, .prefixlen = 10, .label = 11, }, { /* 2002::/16 */ .prefix = &(struct in6_addr){ { { 0x20, 0x02 } } }, .prefixlen = 16, .label = 2, }, { /* 3ffe::/16 */ .prefix = &(struct in6_addr){ { { 0x3f, 0xfe } } }, .prefixlen = 16, .label = 12, }, { /* 2001::/32 */ .prefix = &(struct in6_addr){ { { 0x20, 0x01 } } }, .prefixlen = 32, .label = 6, }, { /* 2001:10::/28 */ .prefix = &(struct in6_addr){ { { 0x20, 0x01, 0x00, 0x10 } } }, .prefixlen = 28, .label = 7, }, { /* ::ffff:0:0 */ .prefix = &(struct in6_addr){ { { [10] = 0xff, [11] = 0xff } } }, .prefixlen = 96, .label = 4, }, { /* ::/96 */ .prefix = &in6addr_any, .prefixlen = 96, .label = 3, }, { /* ::1/128 */ .prefix = &in6addr_loopback, .prefixlen = 128, .label = 0, } }; /* Object management */
static inline void ip6addrlbl_free(struct ip6addrlbl_entry *p) { kfree(p); }

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hideaki yoshifujihideaki yoshifuji17100.00%1100.00%
Total17100.00%1100.00%


static void ip6addrlbl_free_rcu(struct rcu_head *h) { ip6addrlbl_free(container_of(h, struct ip6addrlbl_entry, rcu)); }

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hideaki yoshifujihideaki yoshifuji24100.00%1100.00%
Total24100.00%1100.00%


static bool ip6addrlbl_hold(struct ip6addrlbl_entry *p) { return atomic_inc_not_zero(&p->refcnt); }

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hideaki yoshifujihideaki yoshifuji1995.00%150.00%
eric dumazeteric dumazet15.00%150.00%
Total20100.00%2100.00%


static inline void ip6addrlbl_put(struct ip6addrlbl_entry *p) { if (atomic_dec_and_test(&p->refcnt)) call_rcu(&p->rcu, ip6addrlbl_free_rcu); }

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hideaki yoshifujihideaki yoshifuji32100.00%2100.00%
Total32100.00%2100.00%

/* Find label */
static bool __ip6addrlbl_match(struct net *net, const struct ip6addrlbl_entry *p, const struct in6_addr *addr, int addrtype, int ifindex) { if (!net_eq(ip6addrlbl_net(p), net)) return false; if (p->ifindex && p->ifindex != ifindex) return false; if (p->addrtype && p->addrtype != addrtype) return false; if (!ipv6_prefix_equal(addr, &p->prefix, p->prefixlen)) return false; return true; }

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hideaki yoshifujihideaki yoshifuji7172.45%133.33%
benjamin therybenjamin thery2020.41%133.33%
eric dumazeteric dumazet77.14%133.33%
Total98100.00%3100.00%


static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net, const struct in6_addr *addr, int type, int ifindex) { struct ip6addrlbl_entry *p; hlist_for_each_entry_rcu(p, &ip6addrlbl_table.head, list) { if (__ip6addrlbl_match(net, p, addr, type, ifindex)) return p; } return NULL; }

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hideaki yoshifujihideaki yoshifuji5488.52%150.00%
benjamin therybenjamin thery711.48%150.00%
Total61100.00%2100.00%


u32 ipv6_addr_label(struct net *net, const struct in6_addr *addr, int type, int ifindex) { u32 label; struct ip6addrlbl_entry *p; type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK; rcu_read_lock(); p = __ipv6_addr_label(net, addr, type, ifindex); label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT; rcu_read_unlock(); ADDRLABEL(KERN_DEBUG "%s(addr=%pI6, type=%d, ifindex=%d) => %08x\n", __func__, addr, type, ifindex, label); return label; }

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hideaki yoshifujihideaki yoshifuji7789.53%125.00%
benjamin therybenjamin thery78.14%125.00%
harvey harrisonharvey harrison22.33%250.00%
Total86100.00%4100.00%

/* allocate one entry */
static struct ip6addrlbl_entry *ip6addrlbl_alloc(struct net *net, const struct in6_addr *prefix, int prefixlen, int ifindex, u32 label) { struct ip6addrlbl_entry *newp; int addrtype; ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u)\n", __func__, prefix, prefixlen, ifindex, (unsigned int)label); addrtype = ipv6_addr_type(prefix) & (IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK); switch (addrtype) { case IPV6_ADDR_MAPPED: if (prefixlen > 96) return ERR_PTR(-EINVAL); if (prefixlen < 96) addrtype = 0; break; case IPV6_ADDR_COMPATv4: if (prefixlen != 96) addrtype = 0; break; case IPV6_ADDR_LOOPBACK: if (prefixlen != 128) addrtype = 0; break; } newp = kmalloc(sizeof(*newp), GFP_KERNEL); if (!newp) return ERR_PTR(-ENOMEM); ipv6_addr_prefix(&newp->prefix, prefix, prefixlen); newp->prefixlen = prefixlen; newp->ifindex = ifindex; newp->addrtype = addrtype; newp->label = label; INIT_HLIST_NODE(&newp->list); write_pnet(&newp->lbl_net, net); atomic_set(&newp->refcnt, 1); return newp; }

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hideaki yoshifujihideaki yoshifuji20792.41%233.33%
benjamin therybenjamin thery104.46%116.67%
eric w. biedermaneric w. biederman52.23%116.67%
harvey harrisonharvey harrison20.89%233.33%
Total224100.00%6100.00%

/* add a label */
static int __ip6addrlbl_add(struct ip6addrlbl_entry *newp, int replace) { struct hlist_node *n; struct ip6addrlbl_entry *last = NULL, *p = NULL; int ret = 0; ADDRLABEL(KERN_DEBUG "%s(newp=%p, replace=%d)\n", __func__, newp, replace); hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) { if (p->prefixlen == newp->prefixlen && net_eq(ip6addrlbl_net(p), ip6addrlbl_net(newp)) && p->ifindex == newp->ifindex && ipv6_addr_equal(&p->prefix, &newp->prefix)) { if (!replace) { ret = -EEXIST; goto out; } hlist_replace_rcu(&p->list, &newp->list); ip6addrlbl_put(p); goto out; } else if ((p->prefixlen == newp->prefixlen && !p->ifindex) || (p->prefixlen < newp->prefixlen)) { hlist_add_before_rcu(&newp->list, &p->list); goto out; } last = p; } if (last) hlist_add_behind_rcu(&newp->list, &last->list); else hlist_add_head_rcu(&newp->list, &ip6addrlbl_table.head); out: if (!ret) ip6addrlbl_table.seq++; return ret; }

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hideaki yoshifujihideaki yoshifuji18276.47%233.33%
hannes frederic sowahannes frederic sowa3916.39%116.67%
benjamin therybenjamin thery135.46%116.67%
ken heliasken helias31.26%116.67%
harvey harrisonharvey harrison10.42%116.67%
Total238100.00%6100.00%

/* add a label */
static int ip6addrlbl_add(struct net *net, const struct in6_addr *prefix, int prefixlen, int ifindex, u32 label, int replace) { struct ip6addrlbl_entry *newp; int ret = 0; ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d, label=%u, replace=%d)\n", __func__, prefix, prefixlen, ifindex, (unsigned int)label, replace); newp = ip6addrlbl_alloc(net, prefix, prefixlen, ifindex, label); if (IS_ERR(newp)) return PTR_ERR(newp); spin_lock(&ip6addrlbl_table.lock); ret = __ip6addrlbl_add(newp, replace); spin_unlock(&ip6addrlbl_table.lock); if (ret) ip6addrlbl_free(newp); return ret; }

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hideaki yoshifujihideaki yoshifuji11792.86%240.00%
benjamin therybenjamin thery75.56%120.00%
harvey harrisonharvey harrison21.59%240.00%
Total126100.00%5100.00%

/* remove a label */
static int __ip6addrlbl_del(struct net *net, const struct in6_addr *prefix, int prefixlen, int ifindex) { struct ip6addrlbl_entry *p = NULL; struct hlist_node *n; int ret = -ESRCH; ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n", __func__, prefix, prefixlen, ifindex); hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) { if (p->prefixlen == prefixlen && net_eq(ip6addrlbl_net(p), net) && p->ifindex == ifindex && ipv6_addr_equal(&p->prefix, prefix)) { hlist_del_rcu(&p->list); ip6addrlbl_put(p); ret = 0; break; } } return ret; }

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hideaki yoshifujihideaki yoshifuji10786.29%240.00%
benjamin therybenjamin thery1512.10%120.00%
harvey harrisonharvey harrison21.61%240.00%
Total124100.00%5100.00%


static int ip6addrlbl_del(struct net *net, const struct in6_addr *prefix, int prefixlen, int ifindex) { struct in6_addr prefix_buf; int ret; ADDRLABEL(KERN_DEBUG "%s(prefix=%pI6, prefixlen=%d, ifindex=%d)\n", __func__, prefix, prefixlen, ifindex); ipv6_addr_prefix(&prefix_buf, prefix, prefixlen); spin_lock(&ip6addrlbl_table.lock); ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex); spin_unlock(&ip6addrlbl_table.lock); return ret; }

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hideaki yoshifujihideaki yoshifuji7889.66%240.00%
benjamin therybenjamin thery78.05%120.00%
harvey harrisonharvey harrison22.30%240.00%
Total87100.00%5100.00%

/* add default label */
static int __net_init ip6addrlbl_net_init(struct net *net) { int err = 0; int i; ADDRLABEL(KERN_DEBUG "%s\n", __func__); for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) { int ret = ip6addrlbl_add(net, ip6addrlbl_init_table[i].prefix, ip6addrlbl_init_table[i].prefixlen, 0, ip6addrlbl_init_table[i].label, 0); /* XXX: should we free all rules when we catch an error? */ if (ret && (!err || err != -ENOMEM)) err = ret; } return err; }

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hideaki yoshifujihideaki yoshifuji9190.10%125.00%
benjamin therybenjamin thery87.92%125.00%
joe perchesjoe perches10.99%125.00%
harvey harrisonharvey harrison10.99%125.00%
Total101100.00%4100.00%


static void __net_exit ip6addrlbl_net_exit(struct net *net) { struct ip6addrlbl_entry *p = NULL; struct hlist_node *n; /* Remove all labels belonging to the exiting net */ spin_lock(&ip6addrlbl_table.lock); hlist_for_each_entry_safe(p, n, &ip6addrlbl_table.head, list) { if (net_eq(ip6addrlbl_net(p), net)) { hlist_del_rcu(&p->list); ip6addrlbl_put(p); } } spin_unlock(&ip6addrlbl_table.lock); }

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benjamin therybenjamin thery80100.00%1100.00%
Total80100.00%1100.00%

static struct pernet_operations ipv6_addr_label_ops = { .init = ip6addrlbl_net_init, .exit = ip6addrlbl_net_exit, };
int __init ipv6_addr_label_init(void) { spin_lock_init(&ip6addrlbl_table.lock); return register_pernet_subsys(&ipv6_addr_label_ops); }

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hideaki yoshifujihideaki yoshifuji1878.26%150.00%
benjamin therybenjamin thery521.74%150.00%
Total23100.00%2100.00%


void ipv6_addr_label_cleanup(void) { unregister_pernet_subsys(&ipv6_addr_label_ops); }

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neil hormanneil horman13100.00%1100.00%
Total13100.00%1100.00%

static const struct nla_policy ifal_policy[IFAL_MAX+1] = { [IFAL_ADDRESS] = { .len = sizeof(struct in6_addr), }, [IFAL_LABEL] = { .len = sizeof(u32), }, };
static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh) { struct net *net = sock_net(skb->sk); struct ifaddrlblmsg *ifal; struct nlattr *tb[IFAL_MAX+1]; struct in6_addr *pfx; u32 label; int err = 0; err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy); if (err < 0) return err; ifal = nlmsg_data(nlh); if (ifal->ifal_family != AF_INET6 || ifal->ifal_prefixlen > 128) return -EINVAL; if (!tb[IFAL_ADDRESS]) return -EINVAL; pfx = nla_data(tb[IFAL_ADDRESS]); if (!tb[IFAL_LABEL]) return -EINVAL; label = nla_get_u32(tb[IFAL_LABEL]); if (label == IPV6_ADDR_LABEL_DEFAULT) return -EINVAL; switch (nlh->nlmsg_type) { case RTM_NEWADDRLABEL: if (ifal->ifal_index && !__dev_get_by_index(net, ifal->ifal_index)) return -EINVAL; err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen, ifal->ifal_index, label, nlh->nlmsg_flags & NLM_F_REPLACE); break; case RTM_DELADDRLABEL: err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen, ifal->ifal_index); break; default: err = -EOPNOTSUPP; } return err; }

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hideaki yoshifujihideaki yoshifuji21786.80%240.00%
florian westphalflorian westphal208.00%120.00%
denis v. lunevdenis v. lunev93.60%120.00%
benjamin therybenjamin thery41.60%120.00%
Total250100.00%5100.00%


static void ip6addrlbl_putmsg(struct nlmsghdr *nlh, int prefixlen, int ifindex, u32 lseq) { struct ifaddrlblmsg *ifal = nlmsg_data(nlh); ifal->ifal_family = AF_INET6; ifal->ifal_prefixlen = prefixlen; ifal->ifal_flags = 0; ifal->ifal_index = ifindex; ifal->ifal_seq = lseq; }

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hideaki yoshifujihideaki yoshifuji60100.00%1100.00%
Total60100.00%1100.00%

;
static int ip6addrlbl_fill(struct sk_buff *skb, struct ip6addrlbl_entry *p, u32 lseq, u32 portid, u32 seq, int event, unsigned int flags) { struct nlmsghdr *nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrlblmsg), flags); if (!nlh) return -EMSGSIZE; ip6addrlbl_putmsg(nlh, p->prefixlen, p->ifindex, lseq); if (nla_put_in6_addr(skb, IFAL_ADDRESS, &p->prefix) < 0 || nla_put_u32(skb, IFAL_LABEL, p->label) < 0) { nlmsg_cancel(skb, nlh); return -EMSGSIZE; } nlmsg_end(skb, nlh); return 0; }

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hideaki yoshifujihideaki yoshifuji12695.45%125.00%
johannes bergjohannes berg32.27%125.00%
eric w. biedermaneric w. biederman21.52%125.00%
jiri bencjiri benc10.76%125.00%
Total132100.00%4100.00%


static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb) { struct net *net = sock_net(skb->sk); struct ip6addrlbl_entry *p; int idx = 0, s_idx = cb->args[0]; int err; rcu_read_lock(); hlist_for_each_entry_rcu(p, &ip6addrlbl_table.head, list) { if (idx >= s_idx && net_eq(ip6addrlbl_net(p), net)) { err = ip6addrlbl_fill(skb, p, ip6addrlbl_table.seq, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, RTM_NEWADDRLABEL, NLM_F_MULTI); if (err < 0) break; } idx++; } rcu_read_unlock(); cb->args[0] = idx; return skb->len; }

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hideaki yoshifujihideaki yoshifuji11582.14%228.57%
benjamin therybenjamin thery107.14%114.29%
denis v. lunevdenis v. lunev96.43%114.29%
wang yufenwang yufen42.86%114.29%
johannes bergjohannes berg10.71%114.29%
eric w. biedermaneric w. biederman10.71%114.29%
Total140100.00%7100.00%


static inline int ip6addrlbl_msgsize(void) { return NLMSG_ALIGN(sizeof(struct ifaddrlblmsg)) + nla_total_size(16) /* IFAL_ADDRESS */ + nla_total_size(4); /* IFAL_LABEL */ }

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hideaki yoshifujihideaki yoshifuji3096.77%150.00%
eric dumazeteric dumazet13.23%150.00%
Total31100.00%2100.00%


static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr *nlh) { struct net *net = sock_net(in_skb->sk); struct ifaddrlblmsg *ifal; struct nlattr *tb[IFAL_MAX+1]; struct in6_addr *addr; u32 lseq; int err = 0; struct ip6addrlbl_entry *p; struct sk_buff *skb; err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy); if (err < 0) return err; ifal = nlmsg_data(nlh); if (ifal->ifal_family != AF_INET6 || ifal->ifal_prefixlen != 128) return -EINVAL; if (ifal->ifal_index && !__dev_get_by_index(net, ifal->ifal_index)) return -EINVAL; if (!tb[IFAL_ADDRESS]) return -EINVAL; addr = nla_data(tb[IFAL_ADDRESS]); rcu_read_lock(); p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index); if (p && !ip6addrlbl_hold(p)) p = NULL; lseq = ip6addrlbl_table.seq; rcu_read_unlock()