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Release 4.14 net/netfilter/nfnetlink_acct.c

Directory: net/netfilter
/*
 * (C) 2011 Pablo Neira Ayuso <pablo@netfilter.org>
 * (C) 2011 Intra2net AG <http://www.intra2net.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation (or any later at your option).
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/atomic.h>
#include <linux/refcount.h>
#include <linux/netlink.h>
#include <linux/rculist.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <net/netlink.h>
#include <net/sock.h>

#include <linux/netfilter.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nfnetlink_acct.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
MODULE_DESCRIPTION("nfacct: Extended Netfilter accounting infrastructure");


struct nf_acct {
	
atomic64_t		pkts;
	
atomic64_t		bytes;
	
unsigned long		flags;
	
struct list_head	head;
	
refcount_t		refcnt;
	
char			name[NFACCT_NAME_MAX];
	
struct rcu_head		rcu_head;
	
char			data[0];
};


struct nfacct_filter {
	
u32 value;
	
u32 mask;
};


#define NFACCT_F_QUOTA (NFACCT_F_QUOTA_PKTS | NFACCT_F_QUOTA_BYTES)

#define NFACCT_OVERQUOTA_BIT	2	
/* NFACCT_F_OVERQUOTA */


static int nfnl_acct_new(struct net *net, struct sock *nfnl, struct sk_buff *skb, const struct nlmsghdr *nlh, const struct nlattr * const tb[], struct netlink_ext_ack *extack) { struct nf_acct *nfacct, *matching = NULL; char *acct_name; unsigned int size = 0; u32 flags = 0; if (!tb[NFACCT_NAME]) return -EINVAL; acct_name = nla_data(tb[NFACCT_NAME]); if (strlen(acct_name) == 0) return -EINVAL; list_for_each_entry(nfacct, &net->nfnl_acct_list, head) { if (strncmp(nfacct->name, acct_name, NFACCT_NAME_MAX) != 0) continue; if (nlh->nlmsg_flags & NLM_F_EXCL) return -EEXIST; matching = nfacct; break; } if (matching) { if (nlh->nlmsg_flags & NLM_F_REPLACE) { /* reset counters if you request a replacement. */ atomic64_set(&matching->pkts, 0); atomic64_set(&matching->bytes, 0); smp_mb__before_atomic(); /* reset overquota flag if quota is enabled. */ if ((matching->flags & NFACCT_F_QUOTA)) clear_bit(NFACCT_OVERQUOTA_BIT, &matching->flags); return 0; } return -EBUSY; } if (tb[NFACCT_FLAGS]) { flags = ntohl(nla_get_be32(tb[NFACCT_FLAGS])); if (flags & ~NFACCT_F_QUOTA) return -EOPNOTSUPP; if ((flags & NFACCT_F_QUOTA) == NFACCT_F_QUOTA) return -EINVAL; if (flags & NFACCT_F_OVERQUOTA) return -EINVAL; if ((flags & NFACCT_F_QUOTA) && !tb[NFACCT_QUOTA]) return -EINVAL; size += sizeof(u64); } nfacct = kzalloc(sizeof(struct nf_acct) + size, GFP_KERNEL); if (nfacct == NULL) return -ENOMEM; if (flags & NFACCT_F_QUOTA) { u64 *quota = (u64 *)nfacct->data; *quota = be64_to_cpu(nla_get_be64(tb[NFACCT_QUOTA])); nfacct->flags = flags; } strncpy(nfacct->name, nla_data(tb[NFACCT_NAME]), NFACCT_NAME_MAX); if (tb[NFACCT_BYTES]) { atomic64_set(&nfacct->bytes, be64_to_cpu(nla_get_be64(tb[NFACCT_BYTES]))); } if (tb[NFACCT_PKTS]) { atomic64_set(&nfacct->pkts, be64_to_cpu(nla_get_be64(tb[NFACCT_PKTS]))); } refcount_set(&nfacct->refcnt, 1); list_add_tail_rcu(&nfacct->head, &net->nfnl_acct_list); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso29464.33%436.36%
Mathieu J. Poirier13729.98%19.09%
Phil Turnbull183.94%19.09%
Andreas Schultz30.66%19.09%
Patrick McHardy20.44%19.09%
Alexey Perevalov10.22%19.09%
Elena Reshetova10.22%19.09%
Linus Torvalds10.22%19.09%
Total457100.00%11100.00%


static int nfnl_acct_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type, int event, struct nf_acct *acct) { struct nlmsghdr *nlh; struct nfgenmsg *nfmsg; unsigned int flags = portid ? NLM_F_MULTI : 0; u64 pkts, bytes; u32 old_flags; event = nfnl_msg_type(NFNL_SUBSYS_ACCT, event); nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nfmsg), flags); if (nlh == NULL) goto nlmsg_failure; nfmsg = nlmsg_data(nlh); nfmsg->nfgen_family = AF_UNSPEC; nfmsg->version = NFNETLINK_V0; nfmsg->res_id = 0; if (nla_put_string(skb, NFACCT_NAME, acct->name)) goto nla_put_failure; old_flags = acct->flags; if (type == NFNL_MSG_ACCT_GET_CTRZERO) { pkts = atomic64_xchg(&acct->pkts, 0); bytes = atomic64_xchg(&acct->bytes, 0); smp_mb__before_atomic(); if (acct->flags & NFACCT_F_QUOTA) clear_bit(NFACCT_OVERQUOTA_BIT, &acct->flags); } else { pkts = atomic64_read(&acct->pkts); bytes = atomic64_read(&acct->bytes); } if (nla_put_be64(skb, NFACCT_PKTS, cpu_to_be64(pkts), NFACCT_PAD) || nla_put_be64(skb, NFACCT_BYTES, cpu_to_be64(bytes), NFACCT_PAD) || nla_put_be32(skb, NFACCT_USE, htonl(refcount_read(&acct->refcnt)))) goto nla_put_failure; if (acct->flags & NFACCT_F_QUOTA) { u64 *quota = (u64 *)acct->data; if (nla_put_be32(skb, NFACCT_FLAGS, htonl(old_flags)) || nla_put_be64(skb, NFACCT_QUOTA, cpu_to_be64(*quota), NFACCT_PAD)) goto nla_put_failure; } nlmsg_end(skb, nlh); return skb->len; nlmsg_failure: nla_put_failure: nlmsg_cancel(skb, nlh); return -1; }

Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso24068.57%220.00%
Mathieu J. Poirier7020.00%110.00%
David S. Miller185.14%110.00%
Alexey Perevalov113.14%220.00%
Nicolas Dichtel61.71%110.00%
Eric W. Biedermann30.86%110.00%
Linus Torvalds10.29%110.00%
Elena Reshetova10.29%110.00%
Total350100.00%10100.00%


static int nfnl_acct_dump(struct sk_buff *skb, struct netlink_callback *cb) { struct net *net = sock_net(skb->sk); struct nf_acct *cur, *last; const struct nfacct_filter *filter = cb->data; if (cb->args[2]) return 0; last = (struct nf_acct *)cb->args[1]; if (cb->args[1]) cb->args[1] = 0; rcu_read_lock(); list_for_each_entry_rcu(cur, &net->nfnl_acct_list, head) { if (last) { if (cur != last) continue; last = NULL; } if (filter && (cur->flags & filter->mask) != filter->value) continue; if (nfnl_acct_fill_info(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NFNL_MSG_TYPE(cb->nlh->nlmsg_type), NFNL_MSG_ACCT_NEW, cur) < 0) { cb->args[1] = (unsigned long)cur; break; } } if (!cb->args[1]) cb->args[2] = 1; rcu_read_unlock(); return skb->len; }

Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso17680.37%240.00%
Alexey Perevalov2913.24%120.00%
Andreas Schultz135.94%120.00%
Eric W. Biedermann10.46%120.00%
Total219100.00%5100.00%


static int nfnl_acct_done(struct netlink_callback *cb) { kfree(cb->data); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Alexey Perevalov21100.00%1100.00%
Total21100.00%1100.00%

static const struct nla_policy filter_policy[NFACCT_FILTER_MAX + 1] = { [NFACCT_FILTER_MASK] = { .type = NLA_U32 }, [NFACCT_FILTER_VALUE] = { .type = NLA_U32 }, };
static struct nfacct_filter * nfacct_filter_alloc(const struct nlattr * const attr) { struct nfacct_filter *filter; struct nlattr *tb[NFACCT_FILTER_MAX + 1]; int err; err = nla_parse_nested(tb, NFACCT_FILTER_MAX, attr, filter_policy, NULL); if (err < 0) return ERR_PTR(err); if (!tb[NFACCT_FILTER_MASK] || !tb[NFACCT_FILTER_VALUE]) return ERR_PTR(-EINVAL); filter = kzalloc(sizeof(struct nfacct_filter), GFP_KERNEL); if (!filter) return ERR_PTR(-ENOMEM); filter->mask = ntohl(nla_get_be32(tb[NFACCT_FILTER_MASK])); filter->value = ntohl(nla_get_be32(tb[NFACCT_FILTER_VALUE])); return filter; }

Contributors

PersonTokensPropCommitsCommitProp
Alexey Perevalov11683.45%133.33%
Phil Turnbull2115.11%133.33%
Johannes Berg21.44%133.33%
Total139100.00%3100.00%


static int nfnl_acct_get(struct net *net, struct sock *nfnl, struct sk_buff *skb, const struct nlmsghdr *nlh, const struct nlattr * const tb[], struct netlink_ext_ack *extack) { int ret = -ENOENT; struct nf_acct *cur; char *acct_name; if (nlh->nlmsg_flags & NLM_F_DUMP) { struct netlink_dump_control c = { .dump = nfnl_acct_dump, .done = nfnl_acct_done, }; if (tb[NFACCT_FILTER]) { struct nfacct_filter *filter; filter = nfacct_filter_alloc(tb[NFACCT_FILTER]); if (IS_ERR(filter)) return PTR_ERR(filter); c.data = filter; } return netlink_dump_start(nfnl, skb, nlh, &c); } if (!tb[NFACCT_NAME]) return -EINVAL; acct_name = nla_data(tb[NFACCT_NAME]); list_for_each_entry(cur, &net->nfnl_acct_list, head) { struct sk_buff *skb2; if (strncmp(cur->name, acct_name, NFACCT_NAME_MAX)!= 0) continue; skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (skb2 == NULL) { ret = -ENOMEM; break; } ret = nfnl_acct_fill_info(skb2, NETLINK_CB(skb).portid, nlh->nlmsg_seq, NFNL_MSG_TYPE(nlh->nlmsg_type), NFNL_MSG_ACCT_NEW, cur); if (ret <= 0) { kfree_skb(skb2); break; } ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT); if (ret > 0) ret = 0; /* this avoids a loop in nfnetlink. */ return ret == -EAGAIN ? -ENOBUFS : ret; } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso24882.94%562.50%
Alexey Perevalov4816.05%112.50%
Eric W. Biedermann20.67%112.50%
Andreas Schultz10.33%112.50%
Total299100.00%8100.00%

/* try to delete object, fail if it is still in use. */
static int nfnl_acct_try_del(struct nf_acct *cur) { int ret = 0; /* We want to avoid races with nfnl_acct_put. So only when the current * refcnt is 1, we decrease it to 0. */ if (refcount_dec_if_one(&cur->refcnt)) { /* We are protected by nfnl mutex. */ list_del_rcu(&cur->head); kfree_rcu(cur, rcu_head); } else { ret = -EBUSY; } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso5496.43%133.33%
Liping Zhang11.79%133.33%
Elena Reshetova11.79%133.33%
Total56100.00%3100.00%


static int nfnl_acct_del(struct net *net, struct sock *nfnl, struct sk_buff *skb, const struct nlmsghdr *nlh, const struct nlattr * const tb[], struct netlink_ext_ack *extack) { struct nf_acct *cur, *tmp; int ret = -ENOENT; char *acct_name; if (!tb[NFACCT_NAME]) { list_for_each_entry_safe(cur, tmp, &net->nfnl_acct_list, head) nfnl_acct_try_del(cur); return 0; } acct_name = nla_data(tb[NFACCT_NAME]); list_for_each_entry(cur, &net->nfnl_acct_list, head) { if (strncmp(cur->name, acct_name, NFACCT_NAME_MAX) != 0) continue; ret = nfnl_acct_try_del(cur); if (ret < 0) return ret; break; } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso13091.55%360.00%
Liping Zhang107.04%120.00%
Andreas Schultz21.41%120.00%
Total142100.00%5100.00%

static const struct nla_policy nfnl_acct_policy[NFACCT_MAX+1] = { [NFACCT_NAME] = { .type = NLA_NUL_STRING, .len = NFACCT_NAME_MAX-1 }, [NFACCT_BYTES] = { .type = NLA_U64 }, [NFACCT_PKTS] = { .type = NLA_U64 }, [NFACCT_FLAGS] = { .type = NLA_U32 }, [NFACCT_QUOTA] = { .type = NLA_U64 }, [NFACCT_FILTER] = {.type = NLA_NESTED }, }; static const struct nfnl_callback nfnl_acct_cb[NFNL_MSG_ACCT_MAX] = { [NFNL_MSG_ACCT_NEW] = { .call = nfnl_acct_new, .attr_count = NFACCT_MAX, .policy = nfnl_acct_policy }, [NFNL_MSG_ACCT_GET] = { .call = nfnl_acct_get, .attr_count = NFACCT_MAX, .policy = nfnl_acct_policy }, [NFNL_MSG_ACCT_GET_CTRZERO] = { .call = nfnl_acct_get, .attr_count = NFACCT_MAX, .policy = nfnl_acct_policy }, [NFNL_MSG_ACCT_DEL] = { .call = nfnl_acct_del, .attr_count = NFACCT_MAX, .policy = nfnl_acct_policy }, }; static const struct nfnetlink_subsystem nfnl_acct_subsys = { .name = "acct", .subsys_id = NFNL_SUBSYS_ACCT, .cb_count = NFNL_MSG_ACCT_MAX, .cb = nfnl_acct_cb, }; MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_ACCT);
struct nf_acct *nfnl_acct_find_get(struct net *net, const char *acct_name) { struct nf_acct *cur, *acct = NULL; rcu_read_lock(); list_for_each_entry_rcu(cur, &net->nfnl_acct_list, head) { if (strncmp(cur->name, acct_name, NFACCT_NAME_MAX)!= 0) continue; if (!try_module_get(THIS_MODULE)) goto err; if (!refcount_inc_not_zero(&cur->refcnt)) { module_put(THIS_MODULE); goto err; } acct = cur; break; } err: rcu_read_unlock(); return acct; }

Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso9493.07%133.33%
Andreas Schultz65.94%133.33%
Elena Reshetova10.99%133.33%
Total101100.00%3100.00%

EXPORT_SYMBOL_GPL(nfnl_acct_find_get);
void nfnl_acct_put(struct nf_acct *acct) { if (refcount_dec_and_test(&acct->refcnt)) kfree_rcu(acct, rcu_head); module_put(THIS_MODULE); }

Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso2268.75%133.33%
Andreas Schultz928.12%133.33%
Elena Reshetova13.12%133.33%
Total32100.00%3100.00%

EXPORT_SYMBOL_GPL(nfnl_acct_put);
void nfnl_acct_update(const struct sk_buff *skb, struct nf_acct *nfacct) { atomic64_inc(&nfacct->pkts); atomic64_add(skb->len, &nfacct->bytes); }

Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso36100.00%1100.00%
Total36100.00%1100.00%

EXPORT_SYMBOL_GPL(nfnl_acct_update);
static void nfnl_overquota_report(struct net *net, struct nf_acct *nfacct) { int ret; struct sk_buff *skb; skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC); if (skb == NULL) return; ret = nfnl_acct_fill_info(skb, 0, 0, NFNL_MSG_ACCT_OVERQUOTA, 0, nfacct); if (ret <= 0) { kfree_skb(skb); return; } netlink_broadcast(net->nfnl, skb, 0, NFNLGRP_ACCT_QUOTA, GFP_ATOMIC); }

Contributors

PersonTokensPropCommitsCommitProp
Mathieu J. Poirier7991.86%150.00%
Liping Zhang78.14%150.00%
Total86100.00%2100.00%


int nfnl_acct_overquota(struct net *net, const struct sk_buff *skb, struct nf_acct *nfacct) { u64 now; u64 *quota; int ret = NFACCT_UNDERQUOTA; /* no place here if we don't have a quota */ if (!(nfacct->flags & NFACCT_F_QUOTA)) return NFACCT_NO_QUOTA; quota = (u64 *)nfacct->data; now = (nfacct->flags & NFACCT_F_QUOTA_PKTS) ? atomic64_read(&nfacct->pkts) : atomic64_read(&nfacct->bytes); ret = now > *quota; if (now >= *quota && !test_and_set_bit(NFACCT_OVERQUOTA_BIT, &nfacct->flags)) { nfnl_overquota_report(net, nfacct); } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Mathieu J. Poirier11393.39%133.33%
Liping Zhang75.79%133.33%
Alexey Perevalov10.83%133.33%
Total121100.00%3100.00%

EXPORT_SYMBOL_GPL(nfnl_acct_overquota);
static int __net_init nfnl_acct_net_init(struct net *net) { INIT_LIST_HEAD(&net->nfnl_acct_list); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Andreas Schultz23100.00%1100.00%
Total23100.00%1100.00%


static void __net_exit nfnl_acct_net_exit(struct net *net) { struct nf_acct *cur, *tmp; list_for_each_entry_safe(cur, tmp, &net->nfnl_acct_list, head) { list_del_rcu(&cur->head); if (refcount_dec_and_test(&cur->refcnt)) kfree_rcu(cur, rcu_head); } }

Contributors

PersonTokensPropCommitsCommitProp
Andreas Schultz5698.25%150.00%
Elena Reshetova11.75%150.00%
Total57100.00%2100.00%

static struct pernet_operations nfnl_acct_ops = { .init = nfnl_acct_net_init, .exit = nfnl_acct_net_exit, };
static int __init nfnl_acct_init(void) { int ret; ret = register_pernet_subsys(&nfnl_acct_ops); if (ret < 0) { pr_err("nfnl_acct_init: failed to register pernet ops\n"); goto err_out; } pr_info("nfnl_acct: registering with nfnetlink.\n"); ret = nfnetlink_subsys_register(&nfnl_acct_subsys); if (ret < 0) { pr_err("nfnl_acct_init: cannot register with nfnetlink.\n"); goto cleanup_pernet; } return 0; cleanup_pernet: unregister_pernet_subsys(&nfnl_acct_ops); err_out: return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso4859.26%150.00%
Andreas Schultz3340.74%150.00%
Total81100.00%2100.00%


static void __exit nfnl_acct_exit(void) { pr_info("nfnl_acct: unregistering from nfnetlink.\n"); nfnetlink_subsys_unregister(&nfnl_acct_subsys); unregister_pernet_subsys(&nfnl_acct_ops); }

Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso2492.31%150.00%
Andreas Schultz27.69%150.00%
Total26100.00%2100.00%

module_init(nfnl_acct_init); module_exit(nfnl_acct_exit);

Overall Contributors

PersonTokensPropCommitsCommitProp
Pablo Neira Ayuso165862.21%830.77%
Mathieu J. Poirier44016.51%13.85%
Alexey Perevalov28910.84%311.54%
Andreas Schultz1656.19%13.85%
Phil Turnbull391.46%27.69%
Liping Zhang250.94%311.54%
David S. Miller180.68%13.85%
Elena Reshetova100.38%13.85%
Eric W. Biedermann60.23%13.85%
Nicolas Dichtel60.23%13.85%
Andrew Morton30.11%13.85%
Linus Torvalds20.08%13.85%
Patrick McHardy20.08%13.85%
Johannes Berg20.08%13.85%
Total2665100.00%26100.00%
Directory: net/netfilter
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