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* SELinux: Convert avc_audit to use lsm_audit.hThomas Liu2009-08-171-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | Convert avc_audit in security/selinux/avc.c to use lsm_audit.h, for better maintainability. - changed selinux to use common_audit_data instead of avc_audit_data - eliminated code in avc.c and used code from lsm_audit.h instead. Had to add a LSM_AUDIT_NO_AUDIT to lsm_audit.h so that avc_audit can call common_lsm_audit and do the pre and post callbacks without doing the actual dump. This makes it so that the patched version behaves the same way as the unpatched version. Also added a denied field to the selinux_audit_data private space, once again to make it so that the patched version behaves like the unpatched. I've tested and confirmed that AVCs look the same before and after this patch. Signed-off-by: Thomas Liu <tliu@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* Revert "SELinux: Convert avc_audit to use lsm_audit.h"James Morris2009-07-131-2/+2
| | | | | | | | This reverts commit 8113a8d80f4c6a3dc3724b39b470f3fee9c426b6. The patch causes a stack overflow on my system during boot. Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: Convert avc_audit to use lsm_audit.hThomas Liu2009-07-131-2/+2
| | | | | | | | | | | | | | | | Convert avc_audit in security/selinux/avc.c to use lsm_audit.h, for better maintainability and for less code duplication. - changed selinux to use common_audit_data instead of avc_audit_data - eliminated code in avc.c and used code from lsm_audit.h instead. I have tested to make sure that the avcs look the same before and after this patch. Signed-off-by: Thomas Liu <tliu@redhat.com> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* net: skb->dst accessorsEric Dumazet2009-06-031-1/+1
| | | | | | | | | | | | | | | | | | Define three accessors to get/set dst attached to a skb struct dst_entry *skb_dst(const struct sk_buff *skb) void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst) void skb_dst_drop(struct sk_buff *skb) This one should replace occurrences of : dst_release(skb->dst) skb->dst = NULL; Delete skb->dst field Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* CRED: Wrap current->cred and a few other accessorsDavid Howells2008-11-141-3/+3
| | | | | | | | | | Wrap current->cred and a few other accessors to hide their actual implementation. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* CRED: Separate task security context from task_structDavid Howells2008-11-141-3/+3
| | | | | | | | | | | | | | | | Separate the task security context from task_struct. At this point, the security data is temporarily embedded in the task_struct with two pointers pointing to it. Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in entry.S via asm-offsets. With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
* Merge branch 'for-linus' of ↵Linus Torvalds2008-04-211-6/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6: SELinux: one little, two little, three little whitespaces, the avc.c saga. SELinux: cleanup on isle selinuxfs.c changing whitespace for fun and profit: policydb.c SELinux: whitespace and formating fixes for hooks.c SELinux: clean up printks SELinux: sidtab.c whitespace, syntax, and static declaraction cleanups SELinux: services.c whitespace, syntax, and static declaraction cleanups SELinux: mls.c whitespace, syntax, and static declaraction cleanups SELinux: hashtab.c whitespace, syntax, and static declaraction cleanups SELinux: ebitmap.c whitespace, syntax, and static declaraction cleanups SELinux: conditional.c whitespace, syntax, and static declaraction cleanups SELinux: avtab.c whitespace, syntax, and static declaraction cleanups SELinux: xfrm.c whitespace, syntax, and static declaraction cleanups SELinux: nlmsgtab.c whitespace, syntax, and static declaraction cleanups SELinux: netnode.c whitespace, syntax, and static declaraction cleanups SELinux: netlink.c whitespace, syntax, and static declaraction cleanups SELinux: netlabel.c whitespace, syntax, and static declaraction cleanups SELinux: netif.c whitespace, syntax, and static declaraction cleanups
| * SELinux: xfrm.c whitespace, syntax, and static declaraction cleanupsEric Paris2008-04-211-6/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch changes xfrm.c to fix whitespace and syntax issues. Things that are fixed may include (does not not have to include) whitespace at end of lines spaces followed by tabs spaces used instead of tabs spacing around parenthesis locateion of { around struct and else clauses location of * in pointer declarations removal of initialization of static data to keep it in the right section useless {} in if statemetns useless checking for NULL before kfree fixing of the indentation depth of switch statements and any number of other things I forgot to mention Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org>
* | security: Remove unnecessary inclusions of asm/semaphore.hMatthew Wilcox2008-04-181-1/+0
|/ | | | | | | None of these files use any of the functionality promised by asm/semaphore.h. Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
* LSM: Make the Labeled IPsec hooks more stack friendlyPaul Moore2008-04-121-23/+16
| | | | | | | | | | | | The xfrm_get_policy() and xfrm_add_pol_expire() put some rather large structs on the stack to work around the LSM API. This patch attempts to fix that problem by changing the LSM API to require only the relevant "security" pointers instead of the entire SPD entry; we do this for all of the security_xfrm_policy*() functions to keep things consistent. Signed-off-by: Paul Moore <paul.moore@hp.com> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* SELinux: Enable dynamic enable/disable of the network access checksPaul Moore2008-01-301-2/+16
| | | | | | | | | | | | | | | | | | | | | | This patch introduces a mechanism for checking when labeled IPsec or SECMARK are in use by keeping introducing a configuration reference counter for each subsystem. In the case of labeled IPsec, whenever a labeled SA or SPD entry is created the labeled IPsec/XFRM reference count is increased and when the entry is removed it is decreased. In the case of SECMARK, when a SECMARK target is created the reference count is increased and later decreased when the target is removed. These reference counters allow SELinux to quickly determine if either of these subsystems are enabled. NetLabel already has a similar mechanism which provides the netlbl_enabled() function. This patch also renames the selinux_relabel_packet_permission() function to selinux_secmark_relabel_packet_permission() as the original name and description were misleading in that they referenced a single packet label which is not the case. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: suppress a warning for 64k pages.Stephen Rothwell2007-11-081-6/+7
| | | | | | | | | On PowerPC allmodconfig build we get this: security/selinux/xfrm.c:214: warning: comparison is always false due to limited range of data type Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: James Morris <jmorris@namei.org>
* sparse pointer use of zero as nullStephen Hemminger2007-10-181-1/+1
| | | | | | | | | | | | | | | | | Get rid of sparse related warnings from places that use integer as NULL pointer. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Cc: Andi Kleen <ak@suse.de> Cc: Jeff Garzik <jeff@garzik.org> Cc: Matt Mackall <mpm@selenic.com> Cc: Ian Kent <raven@themaw.net> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* security: Convert LSM into a static interfaceJames Morris2007-10-171-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Convert LSM into a static interface, as the ability to unload a security module is not required by in-tree users and potentially complicates the overall security architecture. Needlessly exported LSM symbols have been unexported, to help reduce API abuse. Parameters for the capability and root_plug modules are now specified at boot. The SECURITY_FRAMEWORK_VERSION macro has also been removed. In a nutshell, there is no safe way to unload an LSM. The modular interface is thus unecessary and broken infrastructure. It is used only by out-of-tree modules, which are often binary-only, illegal, abusive of the API and dangerous, e.g. silently re-vectoring SELinux. [akpm@linux-foundation.org: cleanups] [akpm@linux-foundation.org: USB Kconfig fix] [randy.dunlap@oracle.com: fix LSM kernel-doc] Signed-off-by: James Morris <jmorris@namei.org> Acked-by: Chris Wright <chrisw@sous-sol.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: "Serge E. Hallyn" <serue@us.ibm.com> Acked-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* SELinux: null-terminate context string in selinux_xfrm_sec_ctx_allocVenkat Yekkirala2007-07-251-1/+2
| | | | | | | | | xfrm_audit_log() expects the context string to be null-terminated which currently doesn't happen with user-supplied contexts. Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: peer secid consolidation for external network labelingPaul Moore2006-12-021-33/+0
| | | | | | | | | | | | Now that labeled IPsec makes use of the peer_sid field in the sk_security_struct we can remove a lot of the special cases between labeled IPsec and NetLabel. In addition, create a new function, security_skb_extlbl_sid(), which we can use in several places to get the security context of the packet's external label which allows us to further simplify the code in a few places. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: Fix SA selection semanticsVenkat Yekkirala2006-12-021-52/+49
| | | | | | | | | | | | | | | | | | | | | Fix the selection of an SA for an outgoing packet to be at the same context as the originating socket/flow. This eliminates the SELinux policy's ability to use/sendto SAs with contexts other than the socket's. With this patch applied, the SELinux policy will require one or more of the following for a socket to be able to communicate with/without SAs: 1. To enable a socket to communicate without using labeled-IPSec SAs: allow socket_t unlabeled_t:association { sendto recvfrom } 2. To enable a socket to communicate with labeled-IPSec SAs: allow socket_t self:association { sendto }; allow socket_t peer_sa_t:association { recvfrom }; Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: Return correct context for SO_PEERSECVenkat Yekkirala2006-12-021-37/+3
| | | | | | | | | Fix SO_PEERSEC for tcp sockets to return the security context of the peer (as represented by the SA from the peer) as opposed to the SA used by the local/source socket. Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Signed-off-by: James Morris <jmorris@namei.org>
* SELinux: Various xfrm labeling fixesVenkat Yekkirala2006-12-021-26/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the upstreaming of the mlsxfrm modification a few months back, testing has resulted in the identification of the following issues/bugs that are resolved in this patch set. 1. Fix the security context used in the IKE negotiation to be the context of the socket as opposed to the context of the SPD rule. 2. Fix SO_PEERSEC for tcp sockets to return the security context of the peer as opposed to the source. 3. Fix the selection of an SA for an outgoing packet to be at the same context as the originating socket/flow. The following would be the result of applying this patchset: - SO_PEERSEC will now correctly return the peer's context. - IKE deamons will receive the context of the source socket/flow as opposed to the SPD rule's context so that the negotiated SA will be at the same context as the source socket/flow. - The SELinux policy will require one or more of the following for a socket to be able to communicate with/without SAs: 1. To enable a socket to communicate without using labeled-IPSec SAs: allow socket_t unlabeled_t:association { sendto recvfrom } 2. To enable a socket to communicate with labeled-IPSec SAs: allow socket_t self:association { sendto }; allow socket_t peer_sa_t:association { recvfrom }; This Patch: Pass correct security context to IKE for use in negotiation Fix the security context passed to IKE for use in negotiation to be the context of the socket as opposed to the context of the SPD rule so that the SA carries the label of the originating socket/flow. Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Signed-off-by: James Morris <jmorris@namei.org>
* IPsec: correct semantics for SELinux policy matchingVenkat Yekkirala2006-10-111-12/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently when an IPSec policy rule doesn't specify a security context, it is assumed to be "unlabeled" by SELinux, and so the IPSec policy rule fails to match to a flow that it would otherwise match to, unless one has explicitly added an SELinux policy rule allowing the flow to "polmatch" to the "unlabeled" IPSec policy rules. In the absence of such an explicitly added SELinux policy rule, the IPSec policy rule fails to match and so the packet(s) flow in clear text without the otherwise applicable xfrm(s) applied. The above SELinux behavior violates the SELinux security notion of "deny by default" which should actually translate to "encrypt by default" in the above case. This was first reported by Evgeniy Polyakov and the way James Morris was seeing the problem was when connecting via IPsec to a confined service on an SELinux box (vsftpd), which did not have the appropriate SELinux policy permissions to send packets via IPsec. With this patch applied, SELinux "polmatching" of flows Vs. IPSec policy rules will only come into play when there's a explicit context specified for the IPSec policy rule (which also means there's corresponding SELinux policy allowing appropriate domains/flows to polmatch to this context). Secondly, when a security module is loaded (in this case, SELinux), the security_xfrm_policy_lookup() hook can return errors other than access denied, such as -EINVAL. We were not handling that correctly, and in fact inverting the return logic and propagating a false "ok" back up to xfrm_lookup(), which then allowed packets to pass as if they were not associated with an xfrm policy. The solution for this is to first ensure that errno values are correctly propagated all the way back up through the various call chains from security_xfrm_policy_lookup(), and handled correctly. Then, flow_cache_lookup() is modified, so that if the policy resolver fails (typically a permission denied via the security module), the flow cache entry is killed rather than having a null policy assigned (which indicates that the packet can pass freely). This also forces any future lookups for the same flow to consult the security module (e.g. SELinux) for current security policy (rather than, say, caching the error on the flow cache entry). This patch: Fix the selinux side of things. This makes sure SELinux polmatching of flow contexts to IPSec policy rules comes into play only when an explicit context is associated with the IPSec policy rule. Also, this no longer defaults the context of a socket policy to the context of the socket since the "no explicit context" case is now handled properly. Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Signed-off-by: James Morris <jmorris@namei.org>
* [MLSXFRM]: Auto-labeling of child socketsVenkat Yekkirala2006-09-221-1/+0
| | | | | | | | | | | | | This automatically labels the TCP, Unix stream, and dccp child sockets as well as openreqs to be at the same MLS level as the peer. This will result in the selection of appropriately labeled IPSec Security Associations. This also uses the sock's sid (as opposed to the isec sid) in SELinux enforcement of secmark in rcv_skb and postroute_last hooks. Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [MLSXFRM]: Default labeling of socket specific IPSec policiesVenkat Yekkirala2006-09-221-11/+22
| | | | | | | | This defaults the label of socket-specific IPSec policies to be the same as the socket they are set on. Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [MLSXFRM]: Add flow labelingVenkat Yekkirala2006-09-221-4/+7
| | | | | | | | | | | | | | | | | | | | | | This labels the flows that could utilize IPSec xfrms at the points the flows are defined so that IPSec policy and SAs at the right label can be used. The following protos are currently not handled, but they should continue to be able to use single-labeled IPSec like they currently do. ipmr ip_gre ipip igmp sit sctp ip6_tunnel (IPv6 over IPv6 tunnel device) decnet Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [MLSXFRM]: Flow based matching of xfrm policy and stateVenkat Yekkirala2006-09-221-33/+166
| | | | | | | | | This implements a seemless mechanism for xfrm policy selection and state matching based on the flow sid. This also includes the necessary SELinux enforcement pieces. Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Remove obsolete #include <linux/config.h>Jörn Engel2006-06-301-1/+0
| | | | | Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [SECMARK]: Add new packet controls to SELinuxJames Morris2006-06-171-9/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add new per-packet access controls to SELinux, replacing the old packet controls. Packets are labeled with the iptables SECMARK and CONNSECMARK targets, then security policy for the packets is enforced with these controls. To allow for a smooth transition to the new controls, the old code is still present, but not active by default. To restore previous behavior, the old controls may be activated at runtime by writing a '1' to /selinux/compat_net, and also via the kernel boot parameter selinux_compat_net. Switching between the network control models requires the security load_policy permission. The old controls will probably eventually be removed and any continued use is discouraged. With this patch, the new secmark controls for SElinux are disabled by default, so existing behavior is entirely preserved, and the user is not affected at all. It also provides a config option to enable the secmark controls by default (which can always be overridden at boot and runtime). It is also noted in the kconfig help that the user will need updated userspace if enabling secmark controls for SELinux and that they'll probably need the SECMARK and CONNMARK targets, and conntrack protocol helpers, although such decisions are beyond the scope of kernel configuration. Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [LSM-IPsec]: SELinux AuthorizeCatherine Zhang2006-06-171-4/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch contains a fix for the previous patch that adds security contexts to IPsec policies and security associations. In the previous patch, no authorization (besides the check for write permissions to SAD and SPD) is required to delete IPsec policies and security assocations with security contexts. Thus a user authorized to change SAD and SPD can bypass the IPsec policy authorization by simply deleteing policies with security contexts. To fix this security hole, an additional authorization check is added for removing security policies and security associations with security contexts. Note that if no security context is supplied on add or present on policy to be deleted, the SELinux module allows the change unconditionally. The hook is called on deletion when no context is present, which we may want to change. At present, I left it up to the module. LSM changes: The patch adds two new LSM hooks: xfrm_policy_delete and xfrm_state_delete. The new hooks are necessary to authorize deletion of IPsec policies that have security contexts. The existing hooks xfrm_policy_free and xfrm_state_free lack the context to do the authorization, so I decided to split authorization of deletion and memory management of security data, as is typical in the LSM interface. Use: The new delete hooks are checked when xfrm_policy or xfrm_state are deleted by either the xfrm_user interface (xfrm_get_policy, xfrm_del_sa) or the pfkey interface (pfkey_spddelete, pfkey_delete). SELinux changes: The new policy_delete and state_delete functions are added. Signed-off-by: Catherine Zhang <cxzhang@watson.ibm.com> Signed-off-by: Trent Jaeger <tjaeger@cse.psu.edu> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [SELINUX] Fix build after ipsec decap state changes.Dave Jones2006-04-091-2/+2
| | | | | | | | | | | security/selinux/xfrm.c: In function 'selinux_socket_getpeer_dgram': security/selinux/xfrm.c:284: error: 'struct sec_path' has no member named 'x' security/selinux/xfrm.c: In function 'selinux_xfrm_sock_rcv_skb': security/selinux/xfrm.c:317: error: 'struct sec_path' has no member named 'x' Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [SECURITY]: TCP/UDP getpeersecCatherine Zhang2006-03-201-0/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch implements an application of the LSM-IPSec networking controls whereby an application can determine the label of the security association its TCP or UDP sockets are currently connected to via getsockopt and the auxiliary data mechanism of recvmsg. Patch purpose: This patch enables a security-aware application to retrieve the security context of an IPSec security association a particular TCP or UDP socket is using. The application can then use this security context to determine the security context for processing on behalf of the peer at the other end of this connection. In the case of UDP, the security context is for each individual packet. An example application is the inetd daemon, which could be modified to start daemons running at security contexts dependent on the remote client. Patch design approach: - Design for TCP The patch enables the SELinux LSM to set the peer security context for a socket based on the security context of the IPSec security association. The application may retrieve this context using getsockopt. When called, the kernel determines if the socket is a connected (TCP_ESTABLISHED) TCP socket and, if so, uses the dst_entry cache on the socket to retrieve the security associations. If a security association has a security context, the context string is returned, as for UNIX domain sockets. - Design for UDP Unlike TCP, UDP is connectionless. This requires a somewhat different API to retrieve the peer security context. With TCP, the peer security context stays the same throughout the connection, thus it can be retrieved at any time between when the connection is established and when it is torn down. With UDP, each read/write can have different peer and thus the security context might change every time. As a result the security context retrieval must be done TOGETHER with the packet retrieval. The solution is to build upon the existing Unix domain socket API for retrieving user credentials. Linux offers the API for obtaining user credentials via ancillary messages (i.e., out of band/control messages that are bundled together with a normal message). Patch implementation details: - Implementation for TCP The security context can be retrieved by applications using getsockopt with the existing SO_PEERSEC flag. As an example (ignoring error checking): getsockopt(sockfd, SOL_SOCKET, SO_PEERSEC, optbuf, &optlen); printf("Socket peer context is: %s\n", optbuf); The SELinux function, selinux_socket_getpeersec, is extended to check for labeled security associations for connected (TCP_ESTABLISHED == sk->sk_state) TCP sockets only. If so, the socket has a dst_cache of struct dst_entry values that may refer to security associations. If these have security associations with security contexts, the security context is returned. getsockopt returns a buffer that contains a security context string or the buffer is unmodified. - Implementation for UDP To retrieve the security context, the application first indicates to the kernel such desire by setting the IP_PASSSEC option via getsockopt. Then the application retrieves the security context using the auxiliary data mechanism. An example server application for UDP should look like this: toggle = 1; toggle_len = sizeof(toggle); setsockopt(sockfd, SOL_IP, IP_PASSSEC, &toggle, &toggle_len); recvmsg(sockfd, &msg_hdr, 0); if (msg_hdr.msg_controllen > sizeof(struct cmsghdr)) { cmsg_hdr = CMSG_FIRSTHDR(&msg_hdr); if (cmsg_hdr->cmsg_len <= CMSG_LEN(sizeof(scontext)) && cmsg_hdr->cmsg_level == SOL_IP && cmsg_hdr->cmsg_type == SCM_SECURITY) { memcpy(&scontext, CMSG_DATA(cmsg_hdr), sizeof(scontext)); } } ip_setsockopt is enhanced with a new socket option IP_PASSSEC to allow a server socket to receive security context of the peer. A new ancillary message type SCM_SECURITY. When the packet is received we get the security context from the sec_path pointer which is contained in the sk_buff, and copy it to the ancillary message space. An additional LSM hook, selinux_socket_getpeersec_udp, is defined to retrieve the security context from the SELinux space. The existing function, selinux_socket_getpeersec does not suit our purpose, because the security context is copied directly to user space, rather than to kernel space. Testing: We have tested the patch by setting up TCP and UDP connections between applications on two machines using the IPSec policies that result in labeled security associations being built. For TCP, we can then extract the peer security context using getsockopt on either end. For UDP, the receiving end can retrieve the security context using the auxiliary data mechanism of recvmsg. Signed-off-by: Catherine Zhang <cxzhang@watson.ibm.com> Acked-by: James Morris <jmorris@namei.org> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* [XFRM]: Fix sparse warning.Luiz Capitulino2006-01-071-1/+1
| | | | | | | | security/selinux/xfrm.c:155:10: warning: Using plain integer as NULL pointer Signed-off-by: Luiz Capitulino <lcapitulino@mandriva.com.br> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [LSM-IPSec]: Corrections to LSM-IPSec NethooksTrent Jaeger2006-01-061-7/+1
| | | | | | | | | | | | | | | This patch contains two corrections to the LSM-IPsec Nethooks patches previously applied. (1) free a security context on a failed insert via xfrm_user interface in xfrm_add_policy. Memory leak. (2) change the authorization of the allocation of a security context in a xfrm_policy or xfrm_state from both relabelfrom and relabelto to setcontext. Signed-off-by: Trent Jaeger <tjaeger@cse.psu.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
* [LSM-IPSec]: Per-packet access control.Trent Jaeger2006-01-031-0/+311
This patch series implements per packet access control via the extension of the Linux Security Modules (LSM) interface by hooks in the XFRM and pfkey subsystems that leverage IPSec security associations to label packets. Extensions to the SELinux LSM are included that leverage the patch for this purpose. This patch implements the changes necessary to the SELinux LSM to create, deallocate, and use security contexts for policies (xfrm_policy) and security associations (xfrm_state) that enable control of a socket's ability to send and receive packets. Patch purpose: The patch is designed to enable the SELinux LSM to implement access control on individual packets based on the strongly authenticated IPSec security association. Such access controls augment the existing ones in SELinux based on network interface and IP address. The former are very coarse-grained, and the latter can be spoofed. By using IPSec, the SELinux can control access to remote hosts based on cryptographic keys generated using the IPSec mechanism. This enables access control on a per-machine basis or per-application if the remote machine is running the same mechanism and trusted to enforce the access control policy. Patch design approach: The patch's main function is to authorize a socket's access to a IPSec policy based on their security contexts. Since the communication is implemented by a security association, the patch ensures that the security association's negotiated and used have the same security context. The patch enables allocation and deallocation of such security contexts for policies and security associations. It also enables copying of the security context when policies are cloned. Lastly, the patch ensures that packets that are sent without using a IPSec security assocation with a security context are allowed to be sent in that manner. A presentation available at www.selinux-symposium.org/2005/presentations/session2/2-3-jaeger.pdf from the SELinux symposium describes the overall approach. Patch implementation details: The function which authorizes a socket to perform a requested operation (send/receive) on a IPSec policy (xfrm_policy) is selinux_xfrm_policy_lookup. The Netfilter and rcv_skb hooks ensure that if a IPSec SA with a securit y association has not been used, then the socket is allowed to send or receive the packet, respectively. The patch implements SELinux function for allocating security contexts when policies (xfrm_policy) are created via the pfkey or xfrm_user interfaces via selinux_xfrm_policy_alloc. When a security association is built, SELinux allocates the security context designated by the XFRM subsystem which is based on that of the authorized policy via selinux_xfrm_state_alloc. When a xfrm_policy is cloned, the security context of that policy, if any, is copied to the clone via selinux_xfrm_policy_clone. When a xfrm_policy or xfrm_state is freed, its security context, if any is also freed at selinux_xfrm_policy_free or selinux_xfrm_state_free. Testing: The SELinux authorization function is tested using ipsec-tools. We created policies and security associations with particular security contexts and added SELinux access control policy entries to verify the authorization decision. We also made sure that packets for which no security context was supplied (which either did or did not use security associations) were authorized using an unlabelled context. Signed-off-by: Trent Jaeger <tjaeger@cse.psu.edu> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>