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@@ -0,0 +1,156 @@
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+/*
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+ * Module for modifying the secmark field of the skb, for use by
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+ * security subsystems.
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+ *
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+ * Based on the nfmark match by:
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+ * (C) 1999-2001 Marc Boucher <marc@mbsi.ca>
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+ *
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+ * (C) 2006 Red Hat, Inc., James Morris <jmorris@redhat.com>
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+ *
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+ * This program is free software; you can redistribute it and/or modify
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+ * it under the terms of the GNU General Public License version 2 as
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+ * published by the Free Software Foundation.
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+ *
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+ */
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+#include <linux/module.h>
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+#include <linux/skbuff.h>
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+#include <linux/selinux.h>
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+#include <linux/netfilter/x_tables.h>
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+#include <linux/netfilter/xt_SECMARK.h>
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+
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+MODULE_LICENSE("GPL");
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+MODULE_AUTHOR("James Morris <jmorris@redhat.com>");
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+MODULE_DESCRIPTION("ip[6]tables SECMARK modification module");
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+MODULE_ALIAS("ipt_SECMARK");
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+MODULE_ALIAS("ip6t_SECMARK");
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+
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+#define PFX "SECMARK: "
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+
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+static u8 mode;
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+
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+static unsigned int target(struct sk_buff **pskb, const struct net_device *in,
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+ const struct net_device *out, unsigned int hooknum,
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+ const struct xt_target *target,
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+ const void *targinfo, void *userinfo)
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+{
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+ u32 secmark = 0;
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+ const struct xt_secmark_target_info *info = targinfo;
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+
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+ BUG_ON(info->mode != mode);
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+
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+ switch (mode) {
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+ case SECMARK_MODE_SEL:
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+ secmark = info->u.sel.selsid;
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+ break;
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+
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+ default:
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+ BUG();
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+ }
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+
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+ if ((*pskb)->secmark != secmark)
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+ (*pskb)->secmark = secmark;
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+
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+ return XT_CONTINUE;
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+}
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+
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+static int checkentry_selinux(struct xt_secmark_target_info *info)
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+{
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+ int err;
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+ struct xt_secmark_target_selinux_info *sel = &info->u.sel;
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+
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+ err = selinux_string_to_sid(sel->selctx, &sel->selsid);
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+ if (err) {
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+ if (err == -EINVAL)
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+ printk(KERN_INFO PFX "invalid SELinux context \'%s\'\n",
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+ sel->selctx);
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+ return 0;
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+ }
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+
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+ if (!sel->selsid) {
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+ printk(KERN_INFO PFX "unable to map SELinux context \'%s\'\n",
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+ sel->selctx);
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+ return 0;
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+ }
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+
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+ err = selinux_relabel_packet_permission(sel->selsid);
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+ if (err) {
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+ printk(KERN_INFO PFX "unable to obtain relabeling permission\n");
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+ return 0;
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+ }
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+
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+ return 1;
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+}
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+
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+static int checkentry(const char *tablename, const void *entry,
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+ const struct xt_target *target, void *targinfo,
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+ unsigned int targinfosize, unsigned int hook_mask)
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+{
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+ struct xt_secmark_target_info *info = targinfo;
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+
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+ if (mode && mode != info->mode) {
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+ printk(KERN_INFO PFX "mode already set to %hu cannot mix with "
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+ "rules for mode %hu\n", mode, info->mode);
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+ return 0;
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+ }
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+
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+ switch (info->mode) {
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+ case SECMARK_MODE_SEL:
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+ if (!checkentry_selinux(info))
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+ return 0;
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+ break;
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+
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+ default:
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+ printk(KERN_INFO PFX "invalid mode: %hu\n", info->mode);
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+ return 0;
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+ }
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+
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+ if (!mode)
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+ mode = info->mode;
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+ return 1;
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+}
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+
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+static struct xt_target ipt_secmark_reg = {
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+ .name = "SECMARK",
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+ .target = target,
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+ .targetsize = sizeof(struct xt_secmark_target_info),
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+ .table = "mangle",
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+ .checkentry = checkentry,
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+ .me = THIS_MODULE,
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+ .family = AF_INET,
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+ .revision = 0,
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+};
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+
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+static struct xt_target ip6t_secmark_reg = {
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+ .name = "SECMARK",
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+ .target = target,
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+ .targetsize = sizeof(struct xt_secmark_target_info),
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+ .table = "mangle",
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+ .checkentry = checkentry,
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+ .me = THIS_MODULE,
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+ .family = AF_INET6,
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+ .revision = 0,
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+};
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+
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+static int __init xt_secmark_init(void)
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+{
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+ int err;
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+
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+ err = xt_register_target(&ipt_secmark_reg);
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+ if (err)
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+ return err;
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+
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+ err = xt_register_target(&ip6t_secmark_reg);
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+ if (err)
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+ xt_unregister_target(&ipt_secmark_reg);
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+
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+ return err;
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+}
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+
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+static void __exit xt_secmark_fini(void)
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+{
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+ xt_unregister_target(&ip6t_secmark_reg);
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+ xt_unregister_target(&ipt_secmark_reg);
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+}
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+
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+module_init(xt_secmark_init);
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+module_exit(xt_secmark_fini);
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