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2006-10-30[NetLabel]: protect the CIPSOv4 socket option from setsockopt()Paul Moore
This patch makes two changes to protect applications from either removing or tampering with the CIPSOv4 IP option on a socket. The first is the requirement that applications have the CAP_NET_RAW capability to set an IPOPT_CIPSO option on a socket; this prevents untrusted applications from setting their own CIPSOv4 security attributes on the packets they send. The second change is to SELinux and it prevents applications from setting any IPv4 options when there is an IPOPT_CIPSO option already present on the socket; this prevents applications from removing CIPSOv4 security attributes from the packets they send. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-10-11IPsec: correct semantics for SELinux policy matchingVenkat Yekkirala
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>
2006-09-26[PATCH] SELinux: convert sbsec semaphore to a mutexEric Paris
This patch converts the semaphore in the superblock security struct to a mutex. No locking changes or other code changes are done. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] SELinux: change isec semaphore to a mutexEric Paris
This patch converts the remaining isec->sem into a mutex. Very similar locking is provided as before only in the faster smaller mutex rather than a semaphore. An out_unlock path is introduced rather than the conditional unlocking found in the original code. Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] selinux: add support for range transitions on object classesDarrel Goeddel
Introduces support for policy version 21. This version of the binary kernel policy allows for defining range transitions on security classes other than the process security class. As always, backwards compatibility for older formats is retained. The security class is read in as specified when using the new format, while the "process" security class is assumed when using an older policy format. Signed-off-by: Darrel Goeddel <dgoeddel@trustedcs.com> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26[PATCH] selinux: enable configuration of max policy versionStephen Smalley
Enable configuration of SELinux maximum supported policy version to support legacy userland (init) that does not gracefully handle kernels that support newer policy versions two or more beyond the installed policy, as in FC3 and FC4. [bunk@stusta.de: improve Kconfig help text] Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Acked-by: Eric Paris <eparis@redhat.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-22[NetLabel]: add some missing #includes to various header filesPaul Moore
Add some missing include files to the NetLabel related header files. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[NetLabel]: uninline selinux_netlbl_inode_permission()Paul Moore
Uninline the selinux_netlbl_inode_permission() at the request of Andrew Morton. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[NetLabel]: Correctly initialize the NetLabel fields.Paul Moore
Fix a problem where the NetLabel specific fields of the sk_security_struct structure were not being initialized early enough in some cases. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[NetLabel]: SELinux supportVenkat Yekkirala
Add NetLabel support to the SELinux LSM and modify the socket_post_create() LSM hook to return an error code. The most significant part of this patch is the addition of NetLabel hooks into the following SELinux LSM hooks: * selinux_file_permission() * selinux_socket_sendmsg() * selinux_socket_post_create() * selinux_socket_sock_rcv_skb() * selinux_socket_getpeersec_stream() * selinux_socket_getpeersec_dgram() * selinux_sock_graft() * selinux_inet_conn_request() The basic reasoning behind this patch is that outgoing packets are "NetLabel'd" by labeling their socket and the NetLabel security attributes are checked via the additional hook in selinux_socket_sock_rcv_skb(). NetLabel itself is only a labeling mechanism, similar to filesystem extended attributes, it is up to the SELinux enforcement mechanism to perform the actual access checks. In addition to the changes outlined above this patch also includes some changes to the extended bitmap (ebitmap) and multi-level security (mls) code to import and export SELinux TE/MLS attributes into and out of NetLabel. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[MLSXFRM]: Fix build with SECURITY_NETWORK_XFRM disabled.Venkat Yekkirala
The following patch will fix the build problem (encountered by Andrew Morton) when SECURITY_NETWORK_XFRM is not enabled. As compared to git-net-selinux_xfrm_decode_session-build-fix.patch in -mm, this patch sets the return parameter sid to SECSID_NULL in selinux_xfrm_decode_session() and handles this value in the caller selinux_inet_conn_request() appropriately. Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[MLSXFRM]: Default labeling of socket specific IPSec policiesVenkat Yekkirala
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>
2006-09-22[MLSXFRM]: Add flow labelingVenkat Yekkirala
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>
2006-09-22[MLSXFRM]: Flow based matching of xfrm policy and stateVenkat Yekkirala
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>
2006-09-22[MLSXFRM]: Add security sid to sockVenkat Yekkirala
This adds security for IP sockets at the sock level. Security at the sock level is needed to enforce the SELinux security policy for security associations even when a sock is orphaned (such as in the TCP LAST_ACK state). This will also be used to enforce SELinux controls over data arriving at or leaving a child socket while it's still waiting to be accepted. Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[MLSXFRM]: Define new SELinux service routineVenkat Yekkirala
This defines a routine that combines the Type Enforcement portion of one sid with the MLS portion from the other sid to arrive at a new sid. This would be used to define a sid for a security association that is to be negotiated by IKE as well as for determing the sid for open requests and connection-oriented child sockets. Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[MLSXFRM]: Granular IPSec associations for use in MLS environmentsVenkat Yekkirala
The current approach to labeling Security Associations for SELinux purposes uses a one-to-one mapping between xfrm policy rules and security associations. This doesn't address the needs of real world MLS (Multi-level System, traditional Bell-LaPadula) environments where a single xfrm policy rule (pertaining to a range, classified to secret for example) might need to map to multiple Security Associations (one each for classified, secret, top secret and all the compartments applicable to these security levels). This patch set addresses the above problem by allowing for the mapping of a single xfrm policy rule to multiple security associations, with each association used in the security context it is defined for. It also includes the security context to be used in IKE negotiation in the acquire messages sent to the IKE daemon so that a unique SA can be negotiated for each unique security context. A couple of bug fixes are also included; checks to make sure the SAs used by a packet match policy (security context-wise) on the inbound and also that the bundle used for the outbound matches the security context of the flow. This patch set also makes the use of the SELinux sid in flow cache lookups seemless by including the sid in the flow key itself. Also, open requests as well as connection-oriented child sockets are labeled automatically to be at the same level as the peer to allow for use of appropriately labeled IPSec associations. Description of changes: A "sid" member has been added to the flow cache key resulting in the sid being available at all needed locations and the flow cache lookups automatically using the sid. The flow sid is derived from the socket on the outbound and the SAs (unlabeled where an SA was not used) on the inbound. Outbound case: 1. Find policy for the socket. 2. OLD: Find an SA that matches the policy. NEW: Find an SA that matches BOTH the policy and the flow/socket. This is necessary since not every SA that matches the policy can be used for the flow/socket. Consider policy range Secret-TS, and SAs each for Secret and TS. We don't want a TS socket to use the Secret SA. Hence the additional check for the SA Vs. flow/socket. 3. NEW: When looking thru bundles for a policy, make sure the flow/socket can use the bundle. If a bundle is not found, create one, calling for IKE if necessary. If using IKE, include the security context in the acquire message to the IKE daemon. Inbound case: 1. OLD: Find policy for the socket. NEW: Find policy for the incoming packet based on the sid of the SA(s) it used or the unlabeled sid if no SAs were used. (Consider a case where a socket is "authorized" for two policies (unclassified-confidential, secret-top_secret). If the packet has come in using a secret SA, we really ought to be using the latter policy (secret-top_secret).) 2. OLD: BUG: No check to see if the SAs used by the packet agree with the policy sec_ctx-wise. (It was indicated in selinux_xfrm_sock_rcv_skb() that this was being accomplished by (x->id.spi == tmpl->id.spi || !tmpl->id.spi) in xfrm_state_ok, but it turns out tmpl->id.spi would normally be zero (unless xfrm policy rules specify one at the template level, which they usually don't). NEW: The socket is checked for access to the SAs used (based on the sid of the SAs) in selinux_xfrm_sock_rcv_skb(). Forward case: This would be Step 1 from the Inbound case, followed by Steps 2 and 3 from the Outbound case. Outstanding items/issues: - Timewait acknowledgements and such are generated in the current/upstream implementation using a NULL socket resulting in the any_socket sid (SYSTEM_HIGH) to be used. This problem is not addressed by this patch set. This patch: Add new flask definitions to SELinux Adds a new avperm "polmatch" to arbitrate flow/state access to a xfrm policy rule. Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-10[PATCH] SELinux: decouple fscontext/context mount optionsEric Paris
Remove the conflict between fscontext and context mount options. If context= is specified without fscontext it will operate just as before, if both are specified we will use mount point labeling and all inodes will get the label specified by context=. The superblock will be labeled with the label of fscontext=, thus affecting operations which check the superblock security context, such as associate permissions. Signed-off-by: Eric Paris <eparis@parisplace.org> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] SELinux: Add sockcreate node to procattr APIEric Paris
Below is a patch to add a new /proc/self/attr/sockcreate A process may write a context into this interface and all subsequent sockets created will be labeled with that context. This is the same idea as the fscreate interface where a process can specify the label of a file about to be created. At this time one envisioned user of this will be xinetd. It will be able to better label sockets for the actual services. At this time all sockets take the label of the creating process, so all xinitd sockets would just be labeled the same. I tested this by creating a tcp sender and listener. The sender was able to write to this new proc file and then create sockets with the specified label. I am able to be sure the new label was used since the avc denial messages kicked out by the kernel included both the new security permission setsockcreate and all the socket denials were for the new label, not the label of the running process. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: James Morris <jmorris@namei.org> Cc: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] keys: add a way to store the appropriate context for newly-created keysMichael LeMay
Add a /proc/<pid>/attr/keycreate entry that stores the appropriate context for newly-created keys. Modify the selinux_key_alloc hook to make use of the new entry. Update the flask headers to include a new "setkeycreate" permission for processes. Update the flask headers to include a new "create" permission for keys. Use the create permission to restrict which SIDs each task can assign to newly-created keys. Add a new parameter to the security hook "security_key_alloc" to indicate whether it is being invoked by the kernel, or from userspace. If it is being invoked by the kernel, the security hook should never fail. Update the documentation to reflect these changes. Signed-off-by: Michael LeMay <mdlemay@epoch.ncsc.mil> Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-22[PATCH] selinux: add hooks for key subsystemMichael LeMay
Introduce SELinux hooks to support the access key retention subsystem within the kernel. Incorporate new flask headers from a modified version of the SELinux reference policy, with support for the new security class representing retained keys. Extend the "key_alloc" security hook with a task parameter representing the intended ownership context for the key being allocated. Attach security information to root's default keyrings within the SELinux initialization routine. Has passed David's testsuite. Signed-off-by: Michael LeMay <mdlemay@epoch.ncsc.mil> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <jmorris@namei.org> Acked-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-17[SECMARK]: Add new packet controls to SELinuxJames Morris
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>
2006-06-17[SECMARK]: Add new flask definitions to SELinuxJames Morris
Secmark implements a new scheme for adding security markings to packets via iptables, as well as changes to SELinux to use these markings for security policy enforcement. The rationale for this scheme is explained and discussed in detail in the original threads: http://thread.gmane.org/gmane.linux.network/34927/ http://thread.gmane.org/gmane.linux.network/35244/ Examples of policy and rulesets, as well as a full archive of patches for iptables and SELinux userland, may be found at: http://people.redhat.com/jmorris/selinux/secmark/ The code has been tested with various compilation options and in several scenarios, including with 'complicated' protocols such as FTP and also with the new generic conntrack code with IPv6 connection tracking. This patch: Add support for a new object class ('packet'), and associated permissions ('send', 'recv', 'relabelto'). These are used to enforce security policy for network packets labeled with SECMARK, and for adding labeling rules. 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>
2006-06-17[SELINUX]: add security class for appletalk socketsChristopher J. PeBenito
Add a security class for appletalk sockets so that they can be distinguished in SELinux policy. Please apply. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17[LSM-IPsec]: SELinux AuthorizeCatherine Zhang
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>
2006-05-03[PATCH] selinux: Clear selinux_enabled flag upon runtime disable.Stephen Smalley
Clear selinux_enabled flag upon runtime disable of SELinux by userspace, and make sure it is defined even if selinux= boot parameter support is not enabled in configuration. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Tested-by: Jon Smirl <jonsmirl@gmail.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-20[SELINUX]: selinux_socket_getpeer_{stream,dgram} fixupCatherine Zhang
Signed-off-by: Catherine Zhang <cxzhang@watson.ibm.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-03-20[SECURITY]: TCP/UDP getpeersecCatherine Zhang
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>
2006-02-01[PATCH] selinux: remove security struct magic number fields and testsStephen Smalley
Remove the SELinux security structure magic number fields and tests, along with some unnecessary tests for NULL security pointers. These fields and tests are leftovers from the early attempts to support SELinux as a loadable module during LSM development. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06[LSM-IPSec]: Corrections to LSM-IPSec NethooksTrent Jaeger
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>
2006-01-03[LSM-IPSec]: Per-packet access control.Trent Jaeger
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>
2005-09-09[PATCH] Remove security_inode_post_create/mkdir/symlink/mknod hooksStephen Smalley
This patch removes the inode_post_create/mkdir/mknod/symlink LSM hooks as they are obsoleted by the new inode_init_security hook that enables atomic inode security labeling. If anyone sees any reason to retain these hooks, please speak now. Also, is anyone using the post_rename/link hooks; if not, those could also be removed. 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>
2005-09-09[PATCH] security: enable atomic inode security labelingStephen Smalley
The following patch set enables atomic security labeling of newly created inodes by altering the fs code to invoke a new LSM hook to obtain the security attribute to apply to a newly created inode and to set up the incore inode security state during the inode creation transaction. This parallels the existing processing for setting ACLs on newly created inodes. Otherwise, it is possible for new inodes to be accessed by another thread via the dcache prior to complete security setup (presently handled by the post_create/mkdir/... LSM hooks in the VFS) and a newly created inode may be left unlabeled on the disk in the event of a crash. SELinux presently works around the issue by ensuring that the incore inode security label is initialized to a special SID that is inaccessible to unprivileged processes (in accordance with policy), thereby preventing inappropriate access but potentially causing false denials on legitimate accesses. A simple test program demonstrates such false denials on SELinux, and the patch solves the problem. Similar such false denials have been encountered in real applications. This patch defines a new inode_init_security LSM hook to obtain the security attribute to apply to a newly created inode and to set up the incore inode security state for it, and adds a corresponding hook function implementation to SELinux. 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>
2005-09-05[PATCH] selinux: Reduce memory use by avtabStephen Smalley
This patch improves memory use by SELinux by both reducing the avtab node size and reducing the number of avtab nodes. The memory savings are substantial, e.g. on a 64-bit system after boot, James Morris reported the following data for the targeted and strict policies: #objs objsize kernmem Targeted: Before: 237888 40 9.1MB After: 19968 24 468KB Strict: Before: 571680 40 21.81MB After: 221052 24 5.06MB The improvement in memory use comes at a cost in the speed of security server computations of access vectors, but these computations are only required on AVC cache misses, and performance measurements by James Morris using a number of benchmarks have shown that the change does not cause any significant degradation. Note that a rebuilt policy via an updated policy toolchain (libsepol/checkpolicy) is required in order to gain the full benefits of this patch, although some memory savings benefits are immediately applied even to older policies (in particular, the reduction in avtab node size). Sources for the updated toolchain are presently available from the sourceforge CVS tree (http://sourceforge.net/cvs/?group_id=21266), and tarballs are available from http://www.flux.utah.edu/~sds. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-28[PATCH] SELinux: default labeling of MLS fieldJames Morris
Implement kernel labeling of the MLS (multilevel security) field of security contexts for files which have no existing MLS field. This is to enable upgrades of a system from non-MLS to MLS without performing a full filesystem relabel including all of the mountpoints, which would be quite painful for users. With this patch, with MLS enabled, if a file has no MLS field, the kernel internally adds an MLS field to the in-core inode (but not to the on-disk file). This MLS field added is the default for the superblock, allowing per-mountpoint control over the values via fixed policy or mount options. This patch has been tested by enabling MLS without relabeling its filesystem, and seems to be working correctly. Signed-off-by: James Morris <jmorris@redhat.com> Signed-off-by: Stephen Smalley <sds@epoch.ncsc.mil> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] selinux: add executable heap checkLorenzo Hernández García-Hierro
This patch,based on sample code by Roland McGrath, adds an execheap permission check that controls the ability to make the heap executable so that this can be prevented in almost all cases (the X server is presently an exception, but this will hopefully be resolved in the future) so that even programs with execmem permission will need to have the anonymous memory mapped in order to make it executable. The only reason that we use a permission check for such restriction (vs. making it unconditional) is that the X module loader presently needs it; it could possibly be made unconditional in the future when X is changed. The policy patch for the execheap permission is available at: http://pearls.tuxedo-es.org/patches/selinux/policy-execheap.patch Signed-off-by: Lorenzo Hernandez Garcia-Hierro <lorenzo@gnu.org> Acked-by: James Morris <jmorris@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] selinux: add executable stack checkLorenzo Hernandez García-Hierro
This patch adds an execstack permission check that controls the ability to make the main process stack executable so that attempts to make the stack executable can still be prevented even if the process is allowed the existing execmem permission in order to e.g. perform runtime code generation. Note that this does not yet address thread stacks. Note also that unlike the execmem check, the execstack check is only applied on mprotect calls, not mmap calls, as the current security_file_mmap hook is not passed the necessary information presently. The original author of the code that makes the distinction of the stack region, is Ingo Molnar, who wrote it within his patch for /proc/<pid>/maps markers. (http://marc.theaimsgroup.com/?l=linux-kernel&m=110719881508591&w=2) The patches also can be found at: http://pearls.tuxedo-es.org/patches/selinux/policy-execstack.patch http://pearls.tuxedo-es.org/patches/selinux/kernel-execstack.patch policy-execstack.patch is the patch that needs to be applied to the policy in order to support the execstack permission and exclude it from general_domain_access within macros/core_macros.te. kernel-execstack.patch adds such permission to the SELinux code within the kernel and adds the proper permission check to the selinux_file_mprotect() hook. Signed-off-by: Lorenzo Hernandez Garcia-Hierro <lorenzo@gnu.org> Acked-by: James Morris <jmorris@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] SELinux: add finer grained permissions to Netlink audit processingJames Morris
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>
2005-04-16[PATCH] SELinux: add support for NETLINK_KOBJECT_UEVENTJames Morris
This patch adds SELinux support for the KOBJECT_UEVENT Netlink family, so that SELinux can apply finer grained controls to it. For example, security policy for hald can be locked down to the KOBJECT_UEVENT Netlink family only. Currently, this family simply defaults to the default Netlink socket class. Note that some new permission definitions are added to sync with changes in the core userspace policy package, which auto-generates header files. 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>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!