diff options
Diffstat (limited to 'net/netfilter/xt_owner.c')
| -rw-r--r-- | net/netfilter/xt_owner.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/net/netfilter/xt_owner.c b/net/netfilter/xt_owner.c new file mode 100644 index 0000000..f19ebd9 --- /dev/null +++ b/net/netfilter/xt_owner.c @@ -0,0 +1,188 @@ +/* + * Kernel module to match various things tied to sockets associated with + * locally generated outgoing packets. + * + * (C) 2000 Marc Boucher <marc@mbsi.ca> + * + * Copyright © CC Computer Consultants GmbH, 2007 - 2008 + * <jengelh@computergmbh.de> + * + * 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. + */ +#include <linux/module.h> +#include <linux/skbuff.h> +#include <linux/file.h> +#include <net/sock.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter/xt_owner.h> +#include <linux/netfilter_ipv4/ipt_owner.h> +#include <linux/netfilter_ipv6/ip6t_owner.h> + +static bool +owner_mt_v0(const struct sk_buff *skb, const struct xt_match_param *par) +{ + const struct ipt_owner_info *info = par->matchinfo; + const struct file *filp; + + if (skb->sk == NULL || skb->sk->sk_socket == NULL) + return false; + + filp = skb->sk->sk_socket->file; + if (filp == NULL) + return false; + + if (info->match & IPT_OWNER_UID) + if ((filp->f_uid != info->uid) ^ + !!(info->invert & IPT_OWNER_UID)) + return false; + + if (info->match & IPT_OWNER_GID) + if ((filp->f_gid != info->gid) ^ + !!(info->invert & IPT_OWNER_GID)) + return false; + + return true; +} + +static bool +owner_mt6_v0(const struct sk_buff *skb, const struct xt_match_param *par) +{ + const struct ip6t_owner_info *info = par->matchinfo; + const struct file *filp; + + if (skb->sk == NULL || skb->sk->sk_socket == NULL) + return false; + + filp = skb->sk->sk_socket->file; + if (filp == NULL) + return false; + + if (info->match & IP6T_OWNER_UID) + if ((filp->f_uid != info->uid) ^ + !!(info->invert & IP6T_OWNER_UID)) + return false; + + if (info->match & IP6T_OWNER_GID) + if ((filp->f_gid != info->gid) ^ + !!(info->invert & IP6T_OWNER_GID)) + return false; + + return true; +} + +static bool +owner_mt(const struct sk_buff *skb, const struct xt_match_param *par) +{ + const struct xt_owner_match_info *info = par->matchinfo; + const struct file *filp; + + if (skb->sk == NULL || skb->sk->sk_socket == NULL) + return (info->match ^ info->invert) == 0; + else if (info->match & info->invert & XT_OWNER_SOCKET) + /* + * Socket exists but user wanted ! --socket-exists. + * (Single ampersands intended.) + */ + return false; + + filp = skb->sk->sk_socket->file; + if (filp == NULL) + return ((info->match ^ info->invert) & + (XT_OWNER_UID | XT_OWNER_GID)) == 0; + + if (info->match & XT_OWNER_UID) + if ((filp->f_uid >= info->uid_min && + filp->f_uid <= info->uid_max) ^ + !(info->invert & XT_OWNER_UID)) + return false; + + if (info->match & XT_OWNER_GID) + if ((filp->f_gid >= info->gid_min && + filp->f_gid <= info->gid_max) ^ + !(info->invert & XT_OWNER_GID)) + return false; + + return true; +} + +static bool owner_mt_check_v0(const struct xt_mtchk_param *par) +{ + const struct ipt_owner_info *info = par->matchinfo; + + if (info->match & (IPT_OWNER_PID | IPT_OWNER_SID | IPT_OWNER_COMM)) { + printk(KERN_WARNING KBUILD_MODNAME + ": PID, SID and command matching is not " + "supported anymore\n"); + return false; + } + + return true; +} + +static bool owner_mt6_check_v0(const struct xt_mtchk_param *par) +{ + const struct ip6t_owner_info *info = par->matchinfo; + + if (info->match & (IP6T_OWNER_PID | IP6T_OWNER_SID)) { + printk(KERN_WARNING KBUILD_MODNAME + ": PID and SID matching is not supported anymore\n"); + return false; + } + + return true; +} + +static struct xt_match owner_mt_reg[] __read_mostly = { + { + .name = "owner", + .revision = 0, + .family = NFPROTO_IPV4, + .match = owner_mt_v0, + .matchsize = sizeof(struct ipt_owner_info), + .checkentry = owner_mt_check_v0, + .hooks = (1 << NF_INET_LOCAL_OUT) | + (1 << NF_INET_POST_ROUTING), + .me = THIS_MODULE, + }, + { + .name = "owner", + .revision = 0, + .family = NFPROTO_IPV6, + .match = owner_mt6_v0, + .matchsize = sizeof(struct ip6t_owner_info), + .checkentry = owner_mt6_check_v0, + .hooks = (1 << NF_INET_LOCAL_OUT) | + (1 << NF_INET_POST_ROUTING), + .me = THIS_MODULE, + }, + { + .name = "owner", + .revision = 1, + .family = NFPROTO_UNSPEC, + .match = owner_mt, + .matchsize = sizeof(struct xt_owner_match_info), + .hooks = (1 << NF_INET_LOCAL_OUT) | + (1 << NF_INET_POST_ROUTING), + .me = THIS_MODULE, + }, +}; + +static int __init owner_mt_init(void) +{ + return xt_register_matches(owner_mt_reg, ARRAY_SIZE(owner_mt_reg)); +} + +static void __exit owner_mt_exit(void) +{ + xt_unregister_matches(owner_mt_reg, ARRAY_SIZE(owner_mt_reg)); +} + +module_init(owner_mt_init); +module_exit(owner_mt_exit); +MODULE_AUTHOR("Jan Engelhardt <jengelh@computergmbh.de>"); +MODULE_DESCRIPTION("Xtables: socket owner matching"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("ipt_owner"); +MODULE_ALIAS("ip6t_owner"); |
