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2005-06-30[PATCH] selinux_sb_copy_data() should not require a whole pageEric Paris
Currently selinux_sb_copy_data requires an entire page be allocated to *orig when the function is called. This "requirement" is based on the fact that we call copy_page(in_save, nosec_save) and in_save = orig when the data is not FS_BINARY_MOUNTDATA. This means that if a caller were to call do_kern_mount with only about 10 bytes of options, they would get passed here and then we would corrupt PAGE_SIZE - 10 bytes of memory (with all zeros.) Currently it appears all in kernel FS's use one page of data so this has not been a problem. An out of kernel FS did just what is described above and it would almost always panic shortly after they tried to mount. From looking else where in the kernel it is obvious that this string of data must always be null terminated. (See example in do_mount where it always zeros the last byte.) Thus I suggest we use strcpy in place of copy_page. In this way we make sure the amount we copy is always less than or equal to the amount we received and since do_mount is zeroing the last byte this should be safe for all. Signed-off-by: Eric Paris <eparis@parisplace.org> Cc: Stephen Smalley <sds@epoch.ncsc.mil> Acked-by: James Morris <jmorris@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] selinux: kfree cleanupJesper Juhl
kfree(NULL) is legal. Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] RCU: clean up a few remaining synchronize_kernel() callsPaul E. McKenney
2.6.12-rc6-mm1 has a few remaining synchronize_kernel()s, some (but not all) in comments. This patch changes these synchronize_kernel() calls (and comments) to synchronize_rcu() or synchronize_sched() as follows: - arch/x86_64/kernel/mce.c mce_read(): change to synchronize_sched() to handle races with machine-check exceptions (synchronize_rcu() would not cut it given RCU implementations intended for hardcore realtime use. - drivers/input/serio/i8042.c i8042_stop(): change to synchronize_sched() to handle races with i8042_interrupt() interrupt handler. Again, synchronize_rcu() would not cut it given RCU implementations intended for hardcore realtime use. - include/*/kdebug.h comments: change to synchronize_sched() to handle races with NMIs. As before, synchronize_rcu() would not cut it... - include/linux/list.h comment: change to synchronize_rcu(), since this comment is for list_del_rcu(). - security/keys/key.c unregister_key_type(): change to synchronize_rcu(), since this is interacting with RCU read side. - security/keys/process_keys.c install_session_keyring(): change to synchronize_rcu(), since this is interacting with RCU read side. Signed-off-by: "Paul E. McKenney" <paulmck@us.ibm.com> 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>
2005-06-24[PATCH] eCryptfs: export user key typeMichael Halcrow
Export this symbol to GPL modules for eCryptfs: an out-of-tree GPL'ed filesystem. Signed off by: Michael Halcrow <mhalcrow@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-24[PATCH] Keys: Make request-key create an authorisation keyDavid Howells
The attached patch makes the following changes: (1) There's a new special key type called ".request_key_auth". This is an authorisation key for when one process requests a key and another process is started to construct it. This type of key cannot be created by the user; nor can it be requested by kernel services. Authorisation keys hold two references: (a) Each refers to a key being constructed. When the key being constructed is instantiated the authorisation key is revoked, rendering it of no further use. (b) The "authorising process". This is either: (i) the process that called request_key(), or: (ii) if the process that called request_key() itself had an authorisation key in its session keyring, then the authorising process referred to by that authorisation key will also be referred to by the new authorisation key. This means that the process that initiated a chain of key requests will authorise the lot of them, and will, by default, wind up with the keys obtained from them in its keyrings. (2) request_key() creates an authorisation key which is then passed to /sbin/request-key in as part of a new session keyring. (3) When request_key() is searching for a key to hand back to the caller, if it comes across an authorisation key in the session keyring of the calling process, it will also search the keyrings of the process specified therein and it will use the specified process's credentials (fsuid, fsgid, groups) to do that rather than the calling process's credentials. This allows a process started by /sbin/request-key to find keys belonging to the authorising process. (4) A key can be read, even if the process executing KEYCTL_READ doesn't have direct read or search permission if that key is contained within the keyrings of a process specified by an authorisation key found within the calling process's session keyring, and is searchable using the credentials of the authorising process. This allows a process started by /sbin/request-key to read keys belonging to the authorising process. (5) The magic KEY_SPEC_*_KEYRING key IDs when passed to KEYCTL_INSTANTIATE or KEYCTL_NEGATE will specify a keyring of the authorising process, rather than the process doing the instantiation. (6) One of the process keyrings can be nominated as the default to which request_key() should attach new keys if not otherwise specified. This is done with KEYCTL_SET_REQKEY_KEYRING and one of the KEY_REQKEY_DEFL_* constants. The current setting can also be read using this call. (7) request_key() is partially interruptible. If it is waiting for another process to finish constructing a key, it can be interrupted. This permits a request-key cycle to be broken without recourse to rebooting. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-Off-By: Benoit Boissinot <benoit.boissinot@ens-lyon.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-24[PATCH] Keys: Use RCU to manage session keyring pointerDavid Howells
The attached patch uses RCU to manage the session keyring pointer in struct signal_struct. This means that searching need not disable interrupts and get a the sighand spinlock to access this pointer. Furthermore, by judicious use of rcu_read_(un)lock(), this patch also avoids the need to take and put refcounts on the session keyring itself, thus saving on even more atomic ops. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-24[PATCH] Keys: Pass session keyring to call_usermodehelper()David Howells
The attached patch makes it possible to pass a session keyring through to the process spawned by call_usermodehelper(). This allows patch 3/3 to pass an authorisation key through to /sbin/request-key, thus permitting better access controls when doing just-in-time key creation. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-24[PATCH] keys: Discard key spinlock and use RCU for key payloadDavid Howells
The attached patch changes the key implementation in a number of ways: (1) It removes the spinlock from the key structure. (2) The key flags are now accessed using atomic bitops instead of write-locking the key spinlock and using C bitwise operators. The three instantiation flags are dealt with with the construction semaphore held during the request_key/instantiate/negate sequence, thus rendering the spinlock superfluous. The key flags are also now bit numbers not bit masks. (3) The key payload is now accessed using RCU. This permits the recursive keyring search algorithm to be simplified greatly since no locks need be taken other than the usual RCU preemption disablement. Searching now does not require any locks or semaphores to be held; merely that the starting keyring be pinned. (4) The keyring payload now includes an RCU head so that it can be disposed of by call_rcu(). This requires that the payload be copied on unlink to prevent introducing races in copy-down vs search-up. (5) The user key payload is now a structure with the data following it. It includes an RCU head like the keyring payload and for the same reason. It also contains a data length because the data length in the key may be changed on another CPU whilst an RCU protected read is in progress on the payload. This would then see the supposed RCU payload and the on-key data length getting out of sync. I'm tempted to drop the key's datalen entirely, except that it's used in conjunction with quota management and so is a little tricky to get rid of. (6) Update the keys documentation. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] setuid core dumpAlan Cox
Add a new `suid_dumpable' sysctl: This value can be used to query and set the core dump mode for setuid or otherwise protected/tainted binaries. The modes are 0 - (default) - traditional behaviour. Any process which has changed privilege levels or is execute only will not be dumped 1 - (debug) - all processes dump core when possible. The core dump is owned by the current user and no security is applied. This is intended for system debugging situations only. Ptrace is unchecked. 2 - (suidsafe) - any binary which normally would not be dumped is dumped readable by root only. This allows the end user to remove such a dump but not access it directly. For security reasons core dumps in this mode will not overwrite one another or other files. This mode is appropriate when adminstrators are attempting to debug problems in a normal environment. (akpm: > > +EXPORT_SYMBOL(suid_dumpable); > > EXPORT_SYMBOL_GPL? No problem to me. > > if (current->euid == current->uid && current->egid == current->gid) > > current->mm->dumpable = 1; > > Should this be SUID_DUMP_USER? Actually the feedback I had from last time was that the SUID_ defines should go because its clearer to follow the numbers. They can go everywhere (and there are lots of places where dumpable is tested/used as a bool in untouched code) > Maybe this should be renamed to `dump_policy' or something. Doing that > would help us catch any code which isn't using the #defines, too. Fair comment. The patch was designed to be easy to maintain for Red Hat rather than for merging. Changing that field would create a gigantic diff because it is used all over the place. ) Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] SELinux: memory leak in selinux_sb_copy_data()Gerald Schaefer
There is a memory leak during mount when SELinux is active and mount options are specified. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Acked-by: Stephen Smalley <sds@epoch.ncsc.mil> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-20[PATCH] sysfs: (rest) if show/store is missing return -EIODmitry Torokhov
sysfs: fix the rest of the kernel so if an attribute doesn't implement show or store method read/write will return -EIO instead of 0 or -EINVAL or -EPERM. Signed-off-by: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-18[NETLINK]: Neighbour table configuration and statistics via rtnetlinkThomas Graf
To retrieve the neighbour tables send RTM_GETNEIGHTBL with the NLM_F_DUMP flag set. Every neighbour table configuration is spread over multiple messages to avoid running into message size limits on systems with many interfaces. The first message in the sequence transports all not device specific data such as statistics, configuration, and the default parameter set. This message is followed by 0..n messages carrying device specific parameter sets. Although the ordering should be sufficient, NDTA_NAME can be used to identify sequences. The initial message can be identified by checking for NDTA_CONFIG. The device specific messages do not contain this TLV but have NDTPA_IFINDEX set to the corresponding interface index. To change neighbour table attributes, send RTM_SETNEIGHTBL with NDTA_NAME set. Changeable attribute include NDTA_THRESH[1-3], NDTA_GC_INTERVAL, and all TLVs in NDTA_PARMS unless marked otherwise. Device specific parameter sets can be changed by setting NDTPA_IFINDEX to the interface index of the corresponding device. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-05-24AUDIT: Fix remaining cases of direct logging of untrusted strings by avc_auditStephen Smalley
Per Steve Grubb's observation that there are some remaining cases where avc_audit() directly logs untrusted strings without escaping them, here is a patch that changes avc_audit() to use audit_log_untrustedstring() or audit_log_hex() as appropriate. Note that d_name.name is nul- terminated by d_alloc(), and that sun_path is nul-terminated by unix_mkname(), so it is not necessary for the AVC to create nul- terminated copies or to alter audit_log_untrustedstring to take a length argument. In the case of an abstract name, we use audit_log_hex() with an explicit length. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-21Fix oops due to thinko in avc_audit()David Woodhouse
When I added the logging of pid= and comm= back to avc_audit() I screwed it up. Put it back how it should be. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-21AUDIT: Avoid sleeping function in SElinux AVC audit.Stephen Smalley
This patch changes the SELinux AVC to defer logging of paths to the audit framework upon syscall exit, by saving a reference to the (dentry,vfsmount) pair in an auxiliary audit item on the current audit context for processing by audit_log_exit. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-19Merge with master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6.gitDavid Woodhouse
2005-05-19Restore logging of pid= and comm= in AVC audit messagesDavid Woodhouse
We turned this all off because the 'exe=' was causing deadlocks on dcache_lock. There's no need to leave the pid and comm out though. They'll all be logged correctly if full auditing is enabled, but we should still print them in case auditing _isn't_ enabled. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-18AUDIT: Treat all user messages identically.David Woodhouse
It's silly to have to add explicit entries for new userspace messages as we invent them. Just treat all messages in the user range the same. Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-17[PATCH] selinux: fix avc_alloc_node() oom with no policy loadedStephen Smalley
This patch should fix the avc_alloc_node() oom condition that Andrew reported when no policy is loaded in SELinux. Prior to this patch, when no policy was loaded, the SELinux "security server" (policy engine) was only returning allowed decisions for the requested permissions for each access check. This caused the cache to thrash when trying to use SELinux for real work with no policy loaded (typically, the no policy loaded state is only for bootstrapping to the point where we can load an initial policy). This patch changes the SELinux security server to return the complete allowed access vector at once, and then to reset the cache after the initial policy load to flush the initial cache state created during bootstrapping. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-13AUDIT: Add message types to audit recordsSteve Grubb
This patch adds more messages types to the audit subsystem so that audit analysis is quicker, intuitive, and more useful. Signed-off-by: Steve Grubb <sgrubb@redhat.com> --- I forgot one type in the big patch. I need to add one for user space originating SE Linux avc messages. This is used by dbus and nscd. -Steve --- Updated to 2.6.12-rc4-mm1. -dwmw2 Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-11Add audit_log_typeChris Wright
Add audit_log_type to allow callers to specify type and pid when logging. Convert audit_log to wrapper around audit_log_type. Could have converted all audit_log callers directly, but common case is default of type AUDIT_KERNEL and pid 0. Update audit_log_start to take type and pid values when creating a new audit_buffer. Move sequences that did audit_log_start, audit_log_format, audit_set_type, audit_log_end, to simply call audit_log_type directly. This obsoletes audit_set_type and audit_set_pid, so remove them. Signed-off-by: Chris Wright <chrisw@osdl.org> Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2005-05-06The attached patch addresses the problem with getting the audit daemon Steve Grubb
shutdown credential information. It creates a new message type AUDIT_TERM_INFO, which is used by the audit daemon to query who issued the shutdown. It requires the placement of a hook function that gathers the information. The hook is after the DAC & MAC checks and before the function returns. Racing threads could overwrite the uid & pid - but they would have to be root and have policy that allows signalling the audit daemon. That should be a manageable risk. The userspace component will be released later in audit 0.7.2. When it receives the TERM signal, it queries the kernel for shutdown information. When it receives it, it writes the message and exits. The message looks like this: type=DAEMON msg=auditd(1114551182.000) auditd normal halt, sending pid=2650 uid=525, auditd pid=1685 Signed-off-by: Steve Grubb <sgrubb@redhat.com> Signed-off-by: David Woodhouse <dwmw2@infradead.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>
2005-05-01[PATCH] SELinux: cleanup ipc_has_permStephen Smalley
This patch removes the sclass argument from ipc_has_perm in the SELinux module, as it can be obtained from the ipc security structure. The use of a separate argument was a legacy of the older precondition function handling in SELinux and is obsolete. Please apply. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-24[SELINUX]: Fix ipv6_skip_exthdr() invocation causing OOPS.Herbert Xu
The SELinux hooks invoke ipv6_skip_exthdr() with an incorrect length final argument. However, the length argument turns out to be superfluous. I was just reading ipv6_skip_exthdr and it occured to me that we can get rid of len altogether. The only place where len is used is to check whether the skb has two bytes for ipv6_opt_hdr. This check is done by skb_header_pointer/skb_copy_bits anyway. Now it might appear that we've made the code slower by deferring the check to skb_copy_bits. However, this check should not trigger in the common case so this is OK. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-18[PATCH] SELinux: fix deadlock on dcache lockStephen Smalley
This fixes a deadlock on the dcache lock detected during testing at IBM by moving the logging of the current executable information from the SELinux avc_audit function to audit_log_exit (via an audit_log_task_info helper) for processing upon syscall exit. For consistency, the patch also removes the logging of other task-related information from avc_audit, deferring handling to audit_log_exit instead. This allows simplification of the avc_audit code, allows the exe information to be obtained more reliably, always includes the comm information (useful for scripts), and avoids including bogus task information for checks performed from irq or softirq. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: James Morris <jmorris@redhat.com> 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>
2005-04-16[PATCH] SELinux: fix bug in Netlink message type detectionJames Morris
This patch fixes a bug in the SELinux Netlink message type detection code, where the wrong constant was being used in a case statement. The incorrect value is not valid for this class of object so it would not have been reached, and fallen through to a default handler for all Netlink 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>
2005-04-16Linux-2.6.12-rc2v2.6.12-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!