diff options
-rw-r--r-- | include/linux/netfilter/xt_SECMARK.h | 26 | ||||
-rw-r--r-- | net/netfilter/Kconfig | 9 | ||||
-rw-r--r-- | net/netfilter/Makefile | 1 | ||||
-rw-r--r-- | net/netfilter/xt_SECMARK.c | 156 |
4 files changed, 192 insertions, 0 deletions
diff --git a/include/linux/netfilter/xt_SECMARK.h b/include/linux/netfilter/xt_SECMARK.h new file mode 100644 index 0000000..c53fbff --- /dev/null +++ b/include/linux/netfilter/xt_SECMARK.h @@ -0,0 +1,26 @@ +#ifndef _XT_SECMARK_H_target +#define _XT_SECMARK_H_target + +/* + * This is intended for use by various security subsystems (but not + * at the same time). + * + * 'mode' refers to the specific security subsystem which the + * packets are being marked for. + */ +#define SECMARK_MODE_SEL 0x01 /* SELinux */ +#define SECMARK_SELCTX_MAX 256 + +struct xt_secmark_target_selinux_info { + u_int32_t selsid; + char selctx[SECMARK_SELCTX_MAX]; +}; + +struct xt_secmark_target_info { + u_int8_t mode; + union { + struct xt_secmark_target_selinux_info sel; + } u; +}; + +#endif /*_XT_SECMARK_H_target */ diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index 85a7e17..10eccdd 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -174,6 +174,15 @@ config NETFILTER_XT_TARGET_NOTRACK If you want to compile it as a module, say M here and read <file:Documentation/modules.txt>. If unsure, say `N'. +config NETFILTER_XT_TARGET_SECMARK + tristate '"SECMARK" target support' + depends on NETFILTER_XTABLES && NETWORK_SECMARK + help + The SECMARK target allows security marking of network + packets, for use with security subsystems. + + To compile it as a module, choose M here. If unsure, say N. + config NETFILTER_XT_MATCH_COMMENT tristate '"comment" match support' depends on NETFILTER_XTABLES diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index df1da25..3645de0 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -28,6 +28,7 @@ obj-$(CONFIG_NETFILTER_XT_TARGET_CONNMARK) += xt_CONNMARK.o obj-$(CONFIG_NETFILTER_XT_TARGET_MARK) += xt_MARK.o obj-$(CONFIG_NETFILTER_XT_TARGET_NFQUEUE) += xt_NFQUEUE.o obj-$(CONFIG_NETFILTER_XT_TARGET_NOTRACK) += xt_NOTRACK.o +obj-$(CONFIG_NETFILTER_XT_TARGET_SECMARK) += xt_SECMARK.o # matches obj-$(CONFIG_NETFILTER_XT_MATCH_COMMENT) += xt_comment.o diff --git a/net/netfilter/xt_SECMARK.c b/net/netfilter/xt_SECMARK.c new file mode 100644 index 0000000..c2ce9c4 --- /dev/null +++ b/net/netfilter/xt_SECMARK.c @@ -0,0 +1,156 @@ +/* + * Module for modifying the secmark field of the skb, for use by + * security subsystems. + * + * Based on the nfmark match by: + * (C) 1999-2001 Marc Boucher <marc@mbsi.ca> + * + * (C) 2006 Red Hat, Inc., James Morris <jmorris@redhat.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. + * + */ +#include <linux/module.h> +#include <linux/skbuff.h> +#include <linux/selinux.h> +#include <linux/netfilter/x_tables.h> +#include <linux/netfilter/xt_SECMARK.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("James Morris <jmorris@redhat.com>"); +MODULE_DESCRIPTION("ip[6]tables SECMARK modification module"); +MODULE_ALIAS("ipt_SECMARK"); +MODULE_ALIAS("ip6t_SECMARK"); + +#define PFX "SECMARK: " + +static u8 mode; + +static unsigned int target(struct sk_buff **pskb, const struct net_device *in, + const struct net_device *out, unsigned int hooknum, + const struct xt_target *target, + const void *targinfo, void *userinfo) +{ + u32 secmark = 0; + const struct xt_secmark_target_info *info = targinfo; + + BUG_ON(info->mode != mode); + + switch (mode) { + case SECMARK_MODE_SEL: + secmark = info->u.sel.selsid; + break; + + default: + BUG(); + } + + if ((*pskb)->secmark != secmark) + (*pskb)->secmark = secmark; + + return XT_CONTINUE; +} + +static int checkentry_selinux(struct xt_secmark_target_info *info) +{ + int err; + struct xt_secmark_target_selinux_info *sel = &info->u.sel; + + err = selinux_string_to_sid(sel->selctx, &sel->selsid); + if (err) { + if (err == -EINVAL) + printk(KERN_INFO PFX "invalid SELinux context \'%s\'\n", + sel->selctx); + return 0; + } + + if (!sel->selsid) { + printk(KERN_INFO PFX "unable to map SELinux context \'%s\'\n", + sel->selctx); + return 0; + } + + err = selinux_relabel_packet_permission(sel->selsid); + if (err) { + printk(KERN_INFO PFX "unable to obtain relabeling permission\n"); + return 0; + } + + return 1; +} + +static int checkentry(const char *tablename, const void *entry, + const struct xt_target *target, void *targinfo, + unsigned int targinfosize, unsigned int hook_mask) +{ + struct xt_secmark_target_info *info = targinfo; + + if (mode && mode != info->mode) { + printk(KERN_INFO PFX "mode already set to %hu cannot mix with " + "rules for mode %hu\n", mode, info->mode); + return 0; + } + + switch (info->mode) { + case SECMARK_MODE_SEL: + if (!checkentry_selinux(info)) + return 0; + break; + + default: + printk(KERN_INFO PFX "invalid mode: %hu\n", info->mode); + return 0; + } + + if (!mode) + mode = info->mode; + return 1; +} + +static struct xt_target ipt_secmark_reg = { + .name = "SECMARK", + .target = target, + .targetsize = sizeof(struct xt_secmark_target_info), + .table = "mangle", + .checkentry = checkentry, + .me = THIS_MODULE, + .family = AF_INET, + .revision = 0, +}; + +static struct xt_target ip6t_secmark_reg = { + .name = "SECMARK", + .target = target, + .targetsize = sizeof(struct xt_secmark_target_info), + .table = "mangle", + .checkentry = checkentry, + .me = THIS_MODULE, + .family = AF_INET6, + .revision = 0, +}; + +static int __init xt_secmark_init(void) +{ + int err; + + err = xt_register_target(&ipt_secmark_reg); + if (err) + return err; + + err = xt_register_target(&ip6t_secmark_reg); + if (err) + xt_unregister_target(&ipt_secmark_reg); + + return err; +} + +static void __exit xt_secmark_fini(void) +{ + xt_unregister_target(&ip6t_secmark_reg); + xt_unregister_target(&ipt_secmark_reg); +} + +module_init(xt_secmark_init); +module_exit(xt_secmark_fini); |