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Release 4.11 net/netfilter/xt_ipvs.c

Directory: net/netfilter
/*
 *      xt_ipvs - kernel module to match IPVS connection properties
 *
 *      Author: Hannes Eder <heder@google.com>
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/spinlock.h>
#include <linux/skbuff.h>
#ifdef CONFIG_IP_VS_IPV6
#include <net/ipv6.h>
#endif
#include <linux/ip_vs.h>
#include <linux/types.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_ipvs.h>
#include <net/netfilter/nf_conntrack.h>

#include <net/ip_vs.h>

MODULE_AUTHOR("Hannes Eder <heder@google.com>");
MODULE_DESCRIPTION("Xtables: match IPVS connection properties");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_ipvs");
MODULE_ALIAS("ip6t_ipvs");

/* borrowed from xt_conntrack */

static bool ipvs_mt_addrcmp(const union nf_inet_addr *kaddr, const union nf_inet_addr *uaddr, const union nf_inet_addr *umask, unsigned int l3proto) { if (l3proto == NFPROTO_IPV4) return ((kaddr->ip ^ uaddr->ip) & umask->ip) == 0; #ifdef CONFIG_IP_VS_IPV6 else if (l3proto == NFPROTO_IPV6) return ipv6_masked_addr_cmp(&kaddr->in6, &umask->in6, &uaddr->in6) == 0; #endif else return false; }

Contributors

PersonTokensPropCommitsCommitProp
Hannes Eder90100.00%1100.00%
Total90100.00%1100.00%


static bool ipvs_mt(const struct sk_buff *skb, struct xt_action_param *par) { const struct xt_ipvs_mtinfo *data = par->matchinfo; struct netns_ipvs *ipvs = net_ipvs(xt_net(par)); /* ipvs_mt_check ensures that family is only NFPROTO_IPV[46]. */ const u_int8_t family = xt_family(par); struct ip_vs_iphdr iph; struct ip_vs_protocol *pp; struct ip_vs_conn *cp; bool match = true; if (data->bitmask == XT_IPVS_IPVS_PROPERTY) { match = skb->ipvs_property ^ !!(data->invert & XT_IPVS_IPVS_PROPERTY); goto out; } /* other flags than XT_IPVS_IPVS_PROPERTY are set */ if (!skb->ipvs_property) { match = false; goto out; } ip_vs_fill_iph_skb(family, skb, true, &iph); if (data->bitmask & XT_IPVS_PROTO) if ((iph.protocol == data->l4proto) ^ !(data->invert & XT_IPVS_PROTO)) { match = false; goto out; } pp = ip_vs_proto_get(iph.protocol); if (unlikely(!pp)) { match = false; goto out; } /* * Check if the packet belongs to an existing entry */ cp = pp->conn_out_get(ipvs, family, skb, &iph); if (unlikely(cp == NULL)) { match = false; goto out; } /* * We found a connection, i.e. ct != 0, make sure to call * __ip_vs_conn_put before returning. In our case jump to out_put_con. */ if (data->bitmask & XT_IPVS_VPORT) if ((cp->vport == data->vport) ^ !(data->invert & XT_IPVS_VPORT)) { match = false; goto out_put_cp; } if (data->bitmask & XT_IPVS_VPORTCTL) if ((cp->control != NULL && cp->control->vport == data->vportctl) ^ !(data->invert & XT_IPVS_VPORTCTL)) { match = false; goto out_put_cp; } if (data->bitmask & XT_IPVS_DIR) { enum ip_conntrack_info ctinfo; struct nf_conn *ct = nf_ct_get(skb, &ctinfo); if (ct == NULL || nf_ct_is_untracked(ct)) { match = false; goto out_put_cp; } if ((ctinfo >= IP_CT_IS_REPLY) ^ !!(data->invert & XT_IPVS_DIR)) { match = false; goto out_put_cp; } } if (data->bitmask & XT_IPVS_METHOD) if (((cp->flags & IP_VS_CONN_F_FWD_MASK) == data->fwd_method) ^ !(data->invert & XT_IPVS_METHOD)) { match = false; goto out_put_cp; } if (data->bitmask & XT_IPVS_VADDR) { if (ipvs_mt_addrcmp(&cp->vaddr, &data->vaddr, &data->vmask, family) ^ !(data->invert & XT_IPVS_VADDR)) { match = false; goto out_put_cp; } } out_put_cp: __ip_vs_conn_put(cp); out: pr_debug("match=%d\n", match); return match; }

Contributors

PersonTokensPropCommitsCommitProp
Hannes Eder47595.77%120.00%
Eric W. Biedermann122.42%120.00%
Pablo Neira Ayuso61.21%120.00%
Alex Gartrell20.40%120.00%
Jesper Dangaard Brouer10.20%120.00%
Total496100.00%5100.00%


static int ipvs_mt_check(const struct xt_mtchk_param *par) { if (par->family != NFPROTO_IPV4 #ifdef CONFIG_IP_VS_IPV6 && par->family != NFPROTO_IPV6 #endif ) { pr_info("protocol family %u not supported\n", par->family); return -EINVAL; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Hannes Eder49100.00%1100.00%
Total49100.00%1100.00%

static struct xt_match xt_ipvs_mt_reg __read_mostly = { .name = "ipvs", .revision = 0, .family = NFPROTO_UNSPEC, .match = ipvs_mt, .checkentry = ipvs_mt_check, .matchsize = XT_ALIGN(sizeof(struct xt_ipvs_mtinfo)), .me = THIS_MODULE, };
static int __init ipvs_mt_init(void) { return xt_register_match(&xt_ipvs_mt_reg); }

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PersonTokensPropCommitsCommitProp
Hannes Eder16100.00%1100.00%
Total16100.00%1100.00%


static void __exit ipvs_mt_exit(void) { xt_unregister_match(&xt_ipvs_mt_reg); }

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PersonTokensPropCommitsCommitProp
Hannes Eder15100.00%1100.00%
Total15100.00%1100.00%

module_init(ipvs_mt_init); module_exit(ipvs_mt_exit);

Overall Contributors

PersonTokensPropCommitsCommitProp
Hannes Eder77797.37%120.00%
Eric W. Biedermann121.50%120.00%
Pablo Neira Ayuso60.75%120.00%
Alex Gartrell20.25%120.00%
Jesper Dangaard Brouer10.13%120.00%
Total798100.00%5100.00%
Directory: net/netfilter
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