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![Eric Paris](/assets/img/avatar_default.png)
Right now secmark has lots of direct selinux calls. Use all LSM calls and remove all SELinux specific knowledge. The only SELinux specific knowledge we leave is the mode. The only point is to make sure that other LSMs at least test this generic code before they assume it works. (They may also have to make changes if they do not represent labels as strings) Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Paul Moore <paul.moore@hp.com> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: James Morris <jmorris@namei.org>
147 lines
3.2 KiB
C
147 lines
3.2 KiB
C
/*
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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) 2006,2008 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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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/module.h>
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#include <linux/security.h>
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#include <linux/skbuff.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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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("James Morris <jmorris@redhat.com>");
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MODULE_DESCRIPTION("Xtables: packet security mark modification");
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MODULE_ALIAS("ipt_SECMARK");
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MODULE_ALIAS("ip6t_SECMARK");
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#define PFX "SECMARK: "
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static u8 mode;
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static unsigned int
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secmark_tg(struct sk_buff *skb, const struct xt_action_param *par)
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{
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u32 secmark = 0;
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const struct xt_secmark_target_info *info = par->targinfo;
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BUG_ON(info->mode != mode);
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switch (mode) {
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case SECMARK_MODE_SEL:
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secmark = info->secid;
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break;
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default:
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BUG();
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}
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skb->secmark = secmark;
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return XT_CONTINUE;
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}
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static int checkentry_lsm(struct xt_secmark_target_info *info)
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{
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int err;
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info->secctx[SECMARK_SECCTX_MAX - 1] = '\0';
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info->secid = 0;
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err = security_secctx_to_secid(info->secctx, strlen(info->secctx),
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&info->secid);
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if (err) {
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if (err == -EINVAL)
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pr_info("invalid security context \'%s\'\n", info->secctx);
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return err;
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}
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if (!info->secid) {
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pr_info("unable to map security context \'%s\'\n", info->secctx);
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return -ENOENT;
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}
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err = security_secmark_relabel_packet(info->secid);
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if (err) {
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pr_info("unable to obtain relabeling permission\n");
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return err;
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}
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security_secmark_refcount_inc();
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return 0;
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}
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static int secmark_tg_check(const struct xt_tgchk_param *par)
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{
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struct xt_secmark_target_info *info = par->targinfo;
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int err;
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if (strcmp(par->table, "mangle") != 0 &&
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strcmp(par->table, "security") != 0) {
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pr_info("target only valid in the \'mangle\' "
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"or \'security\' tables, not \'%s\'.\n", par->table);
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return -EINVAL;
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}
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if (mode && mode != info->mode) {
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pr_info("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 -EINVAL;
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}
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switch (info->mode) {
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case SECMARK_MODE_SEL:
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break;
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default:
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pr_info("invalid mode: %hu\n", info->mode);
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return -EINVAL;
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}
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err = checkentry_lsm(info);
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if (err)
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return err;
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if (!mode)
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mode = info->mode;
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return 0;
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}
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static void secmark_tg_destroy(const struct xt_tgdtor_param *par)
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{
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switch (mode) {
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case SECMARK_MODE_SEL:
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security_secmark_refcount_dec();
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}
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}
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static struct xt_target secmark_tg_reg __read_mostly = {
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.name = "SECMARK",
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.revision = 0,
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.family = NFPROTO_UNSPEC,
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.checkentry = secmark_tg_check,
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.destroy = secmark_tg_destroy,
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.target = secmark_tg,
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.targetsize = sizeof(struct xt_secmark_target_info),
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.me = THIS_MODULE,
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};
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static int __init secmark_tg_init(void)
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{
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return xt_register_target(&secmark_tg_reg);
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}
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static void __exit secmark_tg_exit(void)
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{
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xt_unregister_target(&secmark_tg_reg);
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}
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module_init(secmark_tg_init);
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module_exit(secmark_tg_exit);
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