linux/security/selinux/nlmsgtab.c

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/*
* Netlink message type permission tables, for user generated messages.
*
* Author: James Morris <jmorris@redhat.com>
*
* Copyright (C) 2004 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/types.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/if.h>
#include <linux/netfilter_ipv4/ip_queue.h>
#include <linux/inet_diag.h>
#include <linux/xfrm.h>
#include <linux/audit.h>
#include "flask.h"
#include "av_permissions.h"
struct nlmsg_perm {
u16 nlmsg_type;
u32 perm;
};
static struct nlmsg_perm nlmsg_route_perms[] =
{
{ RTM_NEWLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_DELLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_GETLINK, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_SETLINK, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_NEWADDR, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_DELADDR, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_GETADDR, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_NEWROUTE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_DELROUTE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_GETROUTE, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_NEWNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_DELNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_GETNEIGH, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_NEWRULE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_DELRULE, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_GETRULE, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_NEWQDISC, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_DELQDISC, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_GETQDISC, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_NEWTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_DELTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_GETTCLASS, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_NEWTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_DELTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_GETTFILTER, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_NEWACTION, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_DELACTION, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_GETACTION, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_NEWPREFIX, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
{ RTM_GETMULTICAST, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_GETANYCAST, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_GETNEIGHTBL, NETLINK_ROUTE_SOCKET__NLMSG_READ },
{ RTM_SETNEIGHTBL, NETLINK_ROUTE_SOCKET__NLMSG_WRITE },
};
static struct nlmsg_perm nlmsg_firewall_perms[] =
{
{ IPQM_MODE, NETLINK_FIREWALL_SOCKET__NLMSG_WRITE },
{ IPQM_VERDICT, NETLINK_FIREWALL_SOCKET__NLMSG_WRITE },
};
static struct nlmsg_perm nlmsg_tcpdiag_perms[] =
{
{ TCPDIAG_GETSOCK, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
{ DCCPDIAG_GETSOCK, NETLINK_TCPDIAG_SOCKET__NLMSG_READ },
};
static struct nlmsg_perm nlmsg_xfrm_perms[] =
{
{ XFRM_MSG_NEWSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_DELSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_GETSA, NETLINK_XFRM_SOCKET__NLMSG_READ },
{ XFRM_MSG_NEWPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_DELPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_GETPOLICY, NETLINK_XFRM_SOCKET__NLMSG_READ },
{ XFRM_MSG_ALLOCSPI, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_ACQUIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_EXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_UPDPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_UPDSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_POLEXPIRE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_FLUSHSA, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_FLUSHPOLICY, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_NEWAE, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_GETAE, NETLINK_XFRM_SOCKET__NLMSG_READ },
};
static struct nlmsg_perm nlmsg_audit_perms[] =
{
[PATCH] SELinux: add finer grained permissions to Netlink audit processing This patch provides finer grained permissions for the audit family of Netlink sockets under SELinux. 1. We need a way to differentiate between privileged and unprivileged reads of kernel data maintained by the audit subsystem. The AUDIT_GET operation is unprivileged: it returns the current status of the audit subsystem (e.g. whether it's enabled etc.). The AUDIT_LIST operation however returns a list of the current audit ruleset, which is considered privileged by the audit folk. To deal with this, a new SELinux permission has been implemented and applied to the operation: nlmsg_readpriv, which can be allocated to appropriately privileged domains. Unprivileged domains would only be allocated nlmsg_read. 2. There is a requirement for certain domains to generate audit events from userspace. These events need to be collected by the kernel, collated and transmitted sequentially back to the audit daemon. An example is user level login, an auditable event under CAPP, where login-related domains generate AUDIT_USER messages via PAM which are relayed back to auditd via the kernel. To prevent handing out nlmsg_write permissions to such domains, a new permission has been added, nlmsg_relay, which is intended for this type of purpose: data is passed via the kernel back to userspace but no privileged information is written to the kernel. Also, AUDIT_LOGIN messages are now valid only for kernel->user messaging, so this value has been removed from the SELinux nlmsgtab (which is only used to check user->kernel messages). Signed-off-by: James Morris <jmorris@redhat.com> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 15:58:40 +00:00
{ AUDIT_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
{ AUDIT_SET, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
{ AUDIT_LIST, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
{ AUDIT_ADD, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
{ AUDIT_DEL, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
{ AUDIT_LIST_RULES, NETLINK_AUDIT_SOCKET__NLMSG_READPRIV },
{ AUDIT_ADD_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
{ AUDIT_DEL_RULE, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
[PATCH] SELinux: add finer grained permissions to Netlink audit processing This patch provides finer grained permissions for the audit family of Netlink sockets under SELinux. 1. We need a way to differentiate between privileged and unprivileged reads of kernel data maintained by the audit subsystem. The AUDIT_GET operation is unprivileged: it returns the current status of the audit subsystem (e.g. whether it's enabled etc.). The AUDIT_LIST operation however returns a list of the current audit ruleset, which is considered privileged by the audit folk. To deal with this, a new SELinux permission has been implemented and applied to the operation: nlmsg_readpriv, which can be allocated to appropriately privileged domains. Unprivileged domains would only be allocated nlmsg_read. 2. There is a requirement for certain domains to generate audit events from userspace. These events need to be collected by the kernel, collated and transmitted sequentially back to the audit daemon. An example is user level login, an auditable event under CAPP, where login-related domains generate AUDIT_USER messages via PAM which are relayed back to auditd via the kernel. To prevent handing out nlmsg_write permissions to such domains, a new permission has been added, nlmsg_relay, which is intended for this type of purpose: data is passed via the kernel back to userspace but no privileged information is written to the kernel. Also, AUDIT_LOGIN messages are now valid only for kernel->user messaging, so this value has been removed from the SELinux nlmsgtab (which is only used to check user->kernel messages). Signed-off-by: James Morris <jmorris@redhat.com> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 15:58:40 +00:00
{ AUDIT_USER, NETLINK_AUDIT_SOCKET__NLMSG_RELAY },
{ AUDIT_SIGNAL_INFO, NETLINK_AUDIT_SOCKET__NLMSG_READ },
Audit: add TTY input auditing Add TTY input auditing, used to audit system administrator's actions. This is required by various security standards such as DCID 6/3 and PCI to provide non-repudiation of administrator's actions and to allow a review of past actions if the administrator seems to overstep their duties or if the system becomes misconfigured for unknown reasons. These requirements do not make it necessary to audit TTY output as well. Compared to an user-space keylogger, this approach records TTY input using the audit subsystem, correlated with other audit events, and it is completely transparent to the user-space application (e.g. the console ioctls still work). TTY input auditing works on a higher level than auditing all system calls within the session, which would produce an overwhelming amount of mostly useless audit events. Add an "audit_tty" attribute, inherited across fork (). Data read from TTYs by process with the attribute is sent to the audit subsystem by the kernel. The audit netlink interface is extended to allow modifying the audit_tty attribute, and to allow sending explanatory audit events from user-space (for example, a shell might send an event containing the final command, after the interactive command-line editing and history expansion is performed, which might be difficult to decipher from the TTY input alone). Because the "audit_tty" attribute is inherited across fork (), it would be set e.g. for sshd restarted within an audited session. To prevent this, the audit_tty attribute is cleared when a process with no open TTY file descriptors (e.g. after daemon startup) opens a TTY. See https://www.redhat.com/archives/linux-audit/2007-June/msg00000.html for a more detailed rationale document for an older version of this patch. [akpm@linux-foundation.org: build fix] Signed-off-by: Miloslav Trmac <mitr@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Paul Fulghum <paulkf@microgate.com> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: Steve Grubb <sgrubb@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 06:40:56 +00:00
{ AUDIT_TTY_GET, NETLINK_AUDIT_SOCKET__NLMSG_READ },
{ AUDIT_TTY_SET, NETLINK_AUDIT_SOCKET__NLMSG_WRITE },
};
static int nlmsg_perm(u16 nlmsg_type, u32 *perm, struct nlmsg_perm *tab, size_t tabsize)
{
int i, err = -EINVAL;
for (i = 0; i < tabsize/sizeof(struct nlmsg_perm); i++)
if (nlmsg_type == tab[i].nlmsg_type) {
*perm = tab[i].perm;
err = 0;
break;
}
return err;
}
int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm)
{
int err = 0;
switch (sclass) {
case SECCLASS_NETLINK_ROUTE_SOCKET:
err = nlmsg_perm(nlmsg_type, perm, nlmsg_route_perms,
sizeof(nlmsg_route_perms));
break;
case SECCLASS_NETLINK_FIREWALL_SOCKET:
case SECCLASS_NETLINK_IP6FW_SOCKET:
err = nlmsg_perm(nlmsg_type, perm, nlmsg_firewall_perms,
sizeof(nlmsg_firewall_perms));
break;
case SECCLASS_NETLINK_TCPDIAG_SOCKET:
err = nlmsg_perm(nlmsg_type, perm, nlmsg_tcpdiag_perms,
sizeof(nlmsg_tcpdiag_perms));
break;
case SECCLASS_NETLINK_XFRM_SOCKET:
err = nlmsg_perm(nlmsg_type, perm, nlmsg_xfrm_perms,
sizeof(nlmsg_xfrm_perms));
break;
case SECCLASS_NETLINK_AUDIT_SOCKET:
if ((nlmsg_type >= AUDIT_FIRST_USER_MSG &&
nlmsg_type <= AUDIT_LAST_USER_MSG) ||
(nlmsg_type >= AUDIT_FIRST_USER_MSG2 &&
nlmsg_type <= AUDIT_LAST_USER_MSG2)) {
*perm = NETLINK_AUDIT_SOCKET__NLMSG_RELAY;
} else {
err = nlmsg_perm(nlmsg_type, perm, nlmsg_audit_perms,
sizeof(nlmsg_audit_perms));
}
break;
/* No messaging from userspace, or class unknown/unhandled */
default:
err = -ENOENT;
break;
}
return err;
}