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* Further refine the handling of stop signals in the NFS client. Thejhb2013-02-211-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | changes in r246417 were incomplete as they did not add explicit calls to sigdeferstop() around all the places that previously passed SBDRY to _sleep(). In addition, nfs_getcacheblk() could trigger a write RPC from getblk() resulting in sigdeferstop() recursing. Rather than manually deferring stop signals in specific places, change the VFS_*() and VOP_*() methods to defer stop signals for filesystems which request this behavior via a new VFCF_SBDRY flag. Note that this has to be a VFC flag rather than a MNTK flag so that it works properly with VFS_MOUNT() when the mount is not yet fully constructed. For now, only the NFS clients are set this new flag in VFS_SET(). A few other related changes: - Add an assertion to ensure that TDF_SBDRY doesn't leak to userland. - When a lookup request uses VOP_READLINK() to follow a symlink, mark the request as being on behalf of the thread performing the lookup (cnp_thread) rather than using a NULL thread pointer. This causes NFS to properly handle signals during this VOP on an interruptible mount. PR: kern/176179 Reported by: Russell Cattelan (sigdeferstop() recursion) Reviewed by: kib MFC after: 1 month
* The group list for a non-default export entry (a host/subnet one)rmacklem2012-12-141-1/+1
| | | | | | | | | | was being copied from the wrong place. This patch fixes that. This could cause access failures for mapped users, when the group permissions were needed. PR: 147998 Submitted by: Christopher Key (cjk32 at cam.ac.uk) MFC after: 2 weeks
* Set the prison in NFS anon and GSS SVC creds.jamie2009-09-281-0/+5
| | | | | Reviewed by: marcel MFC after: 3 days
* Free struct ucreds allocated in vfs_hang_addrlist() when deletingkib2009-06-291-4/+14
| | | | | | | | | the export element. While there, remove register storage-class specifiers. Reported and tested by: pho Reviewed by: kan Approved by: re (kensmith)
* Rework the credential code to support larger values of NGROUPS andbrooks2009-06-191-6/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | NGROUPS_MAX, eliminate ABI dependencies on them, and raise the to 1024 and 1023 respectively. (Previously they were equal, but under a close reading of POSIX, NGROUPS_MAX was defined to be too large by 1 since it is the number of supplemental groups, not total number of groups.) The bulk of the change consists of converting the struct ucred member cr_groups from a static array to a pointer. Do the equivalent in kinfo_proc. Introduce new interfaces crcopysafe() and crsetgroups() for duplicating a process credential before modifying it and for setting group lists respectively. Both interfaces take care for the details of allocating groups array. crsetgroups() takes care of truncating the group list to the current maximum (NGROUPS) if necessary. In the future, crsetgroups() may be responsible for insuring invariants such as sorting the supplemental groups to allow groupmember() to be implemented as a binary search. Because we can not change struct xucred without breaking application ABIs, we leave it alone and introduce a new XU_NGROUPS value which is always 16 and is to be used or NGRPS as appropriate for things such as NFS which need to use no more than 16 groups. When feasible, truncate the group list rather than generating an error. Minor changes: - Reduce the number of hand rolled versions of groupmember(). - Do not assign to both cr_gid and cr_groups[0]. - Modify ipfw to cache ucreds instead of part of their contents since they are immutable once referenced by more than one entity. Submitted by: Isilon Systems (initial implementation) X-MFC after: never PR: bin/113398 kern/133867
* Remove the thread argument from the FSD (File-System Dependent) parts ofattilio2009-05-111-1/+1
| | | | | | | | | | | | | | | | | the VFS. Now all the VFS_* functions and relating parts don't want the context as long as it always refers to curthread. In some points, in particular when dealing with VOPs and functions living in the same namespace (eg. vflush) which still need to be converted, pass curthread explicitly in order to retain the old behaviour. Such loose ends will be fixed ASAP. While here fix a bug: now, UFS_EXTATTR can be compiled alone without the UFS_EXTATTR_AUTOSTART option. VFS KPI is heavilly changed by this commit so thirdy parts modules needs to be recompiled. Bump __FreeBSD_version in order to signal such situation.
* Do not embed struct ucred into larger netcred parent structures.kan2009-05-091-20/+24
| | | | | | | | | | | | | Credential might need to hang around longer than its parent and be used outside of mnt_explock scope controlling netcred lifetime. Use separate reference-counted ucred allocated separately instead. While there, extend mnt_explock coverage in vfs_stdexpcheck and clean-up some unused declarations in new NFS code. Reported by: John Hickey PR: kern/133439 Reviewed by: dfr, kib
* drop rnh lock before destroying itkmacy2008-12-281-0/+1
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* - convert radix node head lock from mutex to rwlockkmacy2008-12-071-2/+3
| | | | | | | | - make radix node head lock not recursive - fix LOR in rtexpunge - fix LOR in rtredirect Reviewed by: sam
* Correct typo in comment: thier -> theiremaste2008-11-241-1/+1
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* Implement support for RPCSEC_GSS authentication to both the NFS clientdfr2008-11-031-1/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | and server. This replaces the RPC implementation of the NFS client and server with the newer RPC implementation originally developed (actually ported from the userland sunrpc code) to support the NFS Lock Manager. I have tested this code extensively and I believe it is stable and that performance is at least equal to the legacy RPC implementation. The NFS code currently contains support for both the new RPC implementation and the older legacy implementation inherited from the original NFS codebase. The default is to use the new implementation - add the NFS_LEGACYRPC option to fall back to the old code. When I merge this support back to RELENG_7, I will probably change this so that users have to 'opt in' to get the new code. To use RPCSEC_GSS on either client or server, you must build a kernel which includes the KGSSAPI option and the crypto device. On the userland side, you must build at least a new libc, mountd, mount_nfs and gssd. You must install new versions of /etc/rc.d/gssd and /etc/rc.d/nfsd and add 'gssd_enable=YES' to /etc/rc.conf. As long as gssd is running, you should be able to mount an NFS filesystem from a server that requires RPCSEC_GSS authentication. The mount itself can happen without any kerberos credentials but all access to the filesystem will be denied unless the accessing user has a valid ticket file in the standard place (/tmp/krb5cc_<uid>). There is currently no support for situations where the ticket file is in a different place, such as when the user logged in via SSH and has delegated credentials from that login. This restriction is also present in Solaris and Linux. In theory, we could improve this in future, possibly using Brooks Davis' implementation of variant symlinks. Supporting RPCSEC_GSS on a server is nearly as simple. You must create service creds for the server in the form 'nfs/<fqdn>@<REALM>' and install them in /etc/krb5.keytab. The standard heimdal utility ktutil makes this fairly easy. After the service creds have been created, you can add a '-sec=krb5' option to /etc/exports and restart both mountd and nfsd. The only other difference an administrator should notice is that nfsd doesn't fork to create service threads any more. In normal operation, there will be two nfsd processes, one in userland waiting for TCP connections and one in the kernel handling requests. The latter process will create as many kthreads as required - these should be visible via 'top -H'. The code has some support for varying the number of service threads according to load but initially at least, nfsd uses a fixed number of threads according to the value supplied to its '-n' option. Sponsored by: Isilon Systems MFC after: 1 month
* Retire the MALLOC and FREE macros. They are an abomination unto style(9).des2008-10-231-3/+3
| | | | MFC after: 3 months
* Provide the mutual exclusion between the nfs export list modificationskib2008-06-091-0/+4
| | | | | | | | | | | and nfs requests processing. Lockmgr lock provides the shared locking for nfs requests, while exclusive mode is used for modifications. The writer starvation is handled by lockmgr too. Reported by: kris, pho, many Based on the submission by: mohan Tested by: pho MFC after: 2 weeks
* Add code to allow the system to handle multiple routing tables.julian2008-05-091-3/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This particular implementation is designed to be fully backwards compatible and to be MFC-able to 7.x (and 6.x) Currently the only protocol that can make use of the multiple tables is IPv4 Similar functionality exists in OpenBSD and Linux. From my notes: ----- One thing where FreeBSD has been falling behind, and which by chance I have some time to work on is "policy based routing", which allows different packet streams to be routed by more than just the destination address. Constraints: ------------ I want to make some form of this available in the 6.x tree (and by extension 7.x) , but FreeBSD in general needs it so I might as well do it in -current and back port the portions I need. One of the ways that this can be done is to have the ability to instantiate multiple kernel routing tables (which I will now refer to as "Forwarding Information Bases" or "FIBs" for political correctness reasons). Which FIB a particular packet uses to make the next hop decision can be decided by a number of mechanisms. The policies these mechanisms implement are the "Policies" referred to in "Policy based routing". One of the constraints I have if I try to back port this work to 6.x is that it must be implemented as a EXTENSION to the existing ABIs in 6.x so that third party applications do not need to be recompiled in timespan of the branch. This first version will not have some of the bells and whistles that will come with later versions. It will, for example, be limited to 16 tables in the first commit. Implementation method, Compatible version. (part 1) ------------------------------- For this reason I have implemented a "sufficient subset" of a multiple routing table solution in Perforce, and back-ported it to 6.x. (also in Perforce though not always caught up with what I have done in -current/P4). The subset allows a number of FIBs to be defined at compile time (8 is sufficient for my purposes in 6.x) and implements the changes needed to allow IPV4 to use them. I have not done the changes for ipv6 simply because I do not need it, and I do not have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it. Other protocol families are left untouched and should there be users with proprietary protocol families, they should continue to work and be oblivious to the existence of the extra FIBs. To understand how this is done, one must know that the current FIB code starts everything off with a single dimensional array of pointers to FIB head structures (One per protocol family), each of which in turn points to the trie of routes available to that family. The basic change in the ABI compatible version of the change is to extent that array to be a 2 dimensional array, so that instead of protocol family X looking at rt_tables[X] for the table it needs, it looks at rt_tables[Y][X] when for all protocol families except ipv4 Y is always 0. Code that is unaware of the change always just sees the first row of the table, which of course looks just like the one dimensional array that existed before. The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign() are all maintained, but refer only to the first row of the array, so that existing callers in proprietary protocols can continue to do the "right thing". Some new entry points are added, for the exclusive use of ipv4 code called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(), which have an extra argument which refers the code to the correct row. In addition, there are some new entry points (currently called rtalloc_fib() and friends) that check the Address family being looked up and call either rtalloc() (and friends) if the protocol is not IPv4 forcing the action to row 0 or to the appropriate row if it IS IPv4 (and that info is available). These are for calling from code that is not specific to any particular protocol. The way these are implemented would change in the non ABI preserving code to be added later. One feature of the first version of the code is that for ipv4, the interface routes show up automatically on all the FIBs, so that no matter what FIB you select you always have the basic direct attached hosts available to you. (rtinit() does this automatically). You CAN delete an interface route from one FIB should you want to but by default it's there. ARP information is also available in each FIB. It's assumed that the same machine would have the same MAC address, regardless of which FIB you are using to get to it. This brings us as to how the correct FIB is selected for an outgoing IPV4 packet. Firstly, all packets have a FIB associated with them. if nothing has been done to change it, it will be FIB 0. The FIB is changed in the following ways. Packets fall into one of a number of classes. 1/ locally generated packets, coming from a socket/PCB. Such packets select a FIB from a number associated with the socket/PCB. This in turn is inherited from the process, but can be changed by a socket option. The process in turn inherits it on fork. I have written a utility call setfib that acts a bit like nice.. setfib -3 ping target.example.com # will use fib 3 for ping. It is an obvious extension to make it a property of a jail but I have not done so. It can be achieved by combining the setfib and jail commands. 2/ packets received on an interface for forwarding. By default these packets would use table 0, (or possibly a number settable in a sysctl(not yet)). but prior to routing the firewall can inspect them (see below). (possibly in the future you may be able to associate a FIB with packets received on an interface.. An ifconfig arg, but not yet.) 3/ packets inspected by a packet classifier, which can arbitrarily associate a fib with it on a packet by packet basis. A fib assigned to a packet by a packet classifier (such as ipfw) would over-ride a fib associated by a more default source. (such as cases 1 or 2). 4/ a tcp listen socket associated with a fib will generate accept sockets that are associated with that same fib. 5/ Packets generated in response to some other packet (e.g. reset or icmp packets). These should use the FIB associated with the packet being reponded to. 6/ Packets generated during encapsulation. gif, tun and other tunnel interfaces will encapsulate using the FIB that was in effect withthe proces that set up the tunnel. thus setfib 1 ifconfig gif0 [tunnel instructions] will set the fib for the tunnel to use to be fib 1. Routing messages would be associated with their process, and thus select one FIB or another. messages from the kernel would be associated with the fib they refer to and would only be received by a routing socket associated with that fib. (not yet implemented) In addition Netstat has been edited to be able to cope with the fact that the array is now 2 dimensional. (It looks in system memory using libkvm (!)). Old versions of netstat see only the first FIB. In addition two sysctls are added to give: a) the number of FIBs compiled in (active) b) the default FIB of the calling process. Early testing experience: ------------------------- Basically our (IronPort's) appliance does this functionality already using ipfw fwd but that method has some drawbacks. For example, It can't fully simulate a routing table because it can't influence the socket's choice of local address when a connect() is done. Testing during the generating of these changes has been remarkably smooth so far. Multiple tables have co-existed with no notable side effects, and packets have been routes accordingly. ipfw has grown 2 new keywords: setfib N ip from anay to any count ip from any to any fib N In pf there seems to be a requirement to be able to give symbolic names to the fibs but I do not have that capacity. I am not sure if it is required. SCTP has interestingly enough built in support for this, called VRFs in Cisco parlance. it will be interesting to see how that handles it when it suddenly actually does something. Where to next: -------------------- After committing the ABI compatible version and MFCing it, I'd like to proceed in a forward direction in -current. this will result in some roto-tilling in the routing code. Firstly: the current code's idea of having a separate tree per protocol family, all of the same format, and pointed to by the 1 dimensional array is a bit silly. Especially when one considers that there is code that makes assumptions about every protocol having the same internal structures there. Some protocols don't WANT that sort of structure. (for example the whole idea of a netmask is foreign to appletalk). This needs to be made opaque to the external code. My suggested first change is to add routing method pointers to the 'domain' structure, along with information pointing the data. instead of having an array of pointers to uniform structures, there would be an array pointing to the 'domain' structures for each protocol address domain (protocol family), and the methods this reached would be called. The methods would have an argument that gives FIB number, but the protocol would be free to ignore it. When the ABI can be changed it raises the possibilty of the addition of a fib entry into the "struct route". Currently, the structure contains the sockaddr of the desination, and the resulting fib entry. To make this work fully, one could add a fib number so that given an address and a fib, one can find the third element, the fib entry. Interaction with the ARP layer/ LL layer would need to be revisited as well. Qing Li has been working on this already. This work was sponsored by Ironport Systems/Cisco Reviewed by: several including rwatson, bz and mlair (parts each) Obtained from: Ironport systems/Cisco
* Move vnode-to-file-handle translation from vfs_vptofh to vop_vptofh method.pjd2007-02-151-1/+1
| | | | | | | | | | | | | | | | This way we may support multiple structures in v_data vnode field within one file system without using black magic. Vnode-to-file-handle should be VOP in the first place, but was made VFS operation to keep interface as compatible as possible with SUN's VFS. BTW. Now Solaris also implements vnode-to-file-handle as VOP operation. VFS_VPTOFH() was left for API backward compatibility, but is marked for removal before 8.0-RELEASE. Approved by: mckusick Discussed with: many (on IRC) Tested with: ufs, msdosfs, cd9660, nullfs and zfs
* When exiting vfs_export(), delete the "export" option fromrodrigc2007-01-231-11/+31
| | | | | | | | | | | | | | | | | | the mount options list with vfs_deleteopt(). At this point, the export information is saved in mp->mnt_export, so we can delete the "export" mount option from mp->mnt_optnew and mp->mnt_opt. This fixes read-write/read-only update mounts (mount -u -o rw, mount -u -o ro) of NFS exported directories. For some reason, I could only reproduce the problem with a configuration supplied by Andre: - "options QUOTA" enabled in kernel config - "/ -maproot=root 10.0.1.105" in /etc/exports Reported by: kris, Andre Guibert de Bruet <andy siliconlandmark com>, Andrzej Tobola <ato iem pw edu pl> Tested by: Andre Guibert de Bruet
* In vfs_export(), if we specify MNT_DELEXPORT in the struct export_args,rodrigc2006-12-161-1/+4
| | | | | | | | | | | | | after we perform the operations to delete the export, call vfs_deleteopt() to delete the "export" mount option from the linked list of mount options associated with that mount point. This fixes one scenario: - put a filesystem in /etc/exports to export it - remove the filesystem from /etc/exports to delete the export and restart mountd - try to do a "mount -u -o ro" or "mount -u -o rw" on that filesystem now that it is no longer exported.
* Convert to ANSI-style function prototypes.rodrigc2006-12-161-21/+9
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* Use vfs_mount_error() to log mount errors in a few places with humanrodrigc2006-12-071-1/+8
| | | | | readable strings which can be retrieved if an "errmsg" parameter is passed into nmount().
* Use mount interlock to protect all changes to mnt_flag and mnt_kern_flag.tegge2006-09-261-0/+10
| | | | | This eliminates a race where MNT_UPDATE flag could be lost when nmount() raced against sync(), sync_fsync() or quotactl().
* Normalize a significant number of kernel malloc type names:rwatson2005-10-311-1/+1
| | | | | | | | | | | | | | | | | | | - Prefer '_' to ' ', as it results in more easily parsed results in memory monitoring tools such as vmstat. - Remove punctuation that is incompatible with using memory type names as file names, such as '/' characters. - Disambiguate some collisions by adding subsystem prefixes to some memory types. - Generally prefer lower case to upper case. - If the same type is defined in multiple architecture directories, attempt to use the same name in additional cases. Not all instances were caught in this change, so more work is required to finish this conversion. Similar changes are required for UMA zone names.
* Use the refcount API to manage the reference count for user credentialsjhb2005-09-271-2/+3
| | | | | | rather than using pool mutexes. Tested on: i386, alpha, sparc64
* Handle theoretical case of vfs_export being called with both MNT_DELEXPORT andkan2005-05-111-0/+1
| | | | MNT_EXPORT flags set. Do not reuse the memory that has just been freed.
* - Pass LK_EXCLUSIVE to VFS_ROOT() to satisfy the new flags argument. Forjeff2005-03-241-1/+1
| | | | | | now, all calls to VFS_ROOT() should still acquire exclusive locks. Sponsored by: Isilon Systems, Inc.
* Make various mountpoint related functions static.phk2005-02-101-4/+3
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* /* -> /*- for copyright notices, minor format tweaks as necessaryimp2005-01-061-1/+1
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* Sigh. I really need to get an internet connection which is less thancperciva2004-11-291-1/+1
| | | | | | | | 2km away from where I'm living, so that I can fix these typos sooner. s/SA_MAX/AF_MAX/ is previous commit. Reported by: marcus, ups, Yiawei Ye, dwhite
* Check that saddr->sa_family is a sensible value before using it.cperciva2004-11-281-0/+4
| | | | | Reported by: Bryan Fulton and Ted Unangst, Coverity, Inc. Found by: The SWAT analysis tool
* Make VFS_ROOT() and vflush() take a thread argument.alfred2004-07-121-1/+1
| | | | | | This is to allow filesystems to decide based on the passed thread which vnode to return. Several filesystems used curthread, they now use the passed thread.
* Include <sys/mutex.h> and its prerequisite <sys/lock.h> instesd of dependingbde2004-04-211-5/+8
| | | | | | on namespace pollution in <sys/vnode.h>. Sorted includes.
* Remove advertising clause from University of California Regent's license,imp2004-04-051-4/+0
| | | | | | per letter dated July 22, 1999. Approved by: core
* Guard against MLEN growing larger than a uint8_t due to MSIZE grwoing to ascottl2003-07-261-0/+2
| | | | value of 512 in LINT. This keeps gcc from complaining.
* Use __FBSDID().obrien2003-06-111-1/+3
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* Back out M_* changes, per decision of the TRB.imp2003-02-191-3/+3
| | | | Approved by: trb
* Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.alfred2003-01-211-3/+3
| | | | Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.
* SMP locking for radix nodes.hsu2002-12-241-4/+10
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* Partial backout of 1.318, remove error handling added because it may bealfred2002-06-301-15/+3
| | | | | | incorrect. Requested by: bde
* Fix several style bugs:alfred2002-06-291-7/+17
| | | | | | | | | close up the continued line after removing the cast made the line. space before parentheses in indirect function call. Add an addtional error handler case for the results of callback. Submitted by: bde
* Unbreak computation of 'smask' that I broke when removing caddr_t.alfred2002-06-291-1/+1
| | | | Submitted by: bde
* nuke caddr_t.alfred2002-06-281-10/+9
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* Fixed some style bugs in the removal of __P(()). The main ones werebde2002-03-241-1/+1
| | | | | | not removing tabs before "__P((", and not outdenting continuation lines to preserve non-KNF lining up of code with parentheses. Switch to KNF formatting and/or rewrap the whole prototype in some cases.
* Remove __P.alfred2002-03-191-4/+4
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* Check the version of ex_anon (a `struct xucred') before using it todd2002-03-031-0/+10
| | | | | | fill out netc_anon (a `struct ucred'), and add an XXX around the entire operation since it isn't clear whether it's doing the right thing with things like cr_uidinfo and cr_prison.
* Fix some signed/unsigned integer confusion, and add bounds checking ofkris2001-09-101-0/+5
| | | | | | | | arguments to some functions. Obtained from: NetBSD Reviewed by: peter MFC after: 2 weeks
* Since the netexport struct was centralised to 'struct mount',iedowse2001-05-291-1/+1
| | | | | | | | | | | | | attempting to remove nonexistant exports with MNT_DELEXPORT returns an error; before this change it always succeeded. This caused mountd(8) to log "can't delete exports for /whatever" warnings. Change the error code from EINVAL to a more specific ENOENT, and make mountd ignore this error when deleting the export list. I could have just restored the previous behaviour of returning success, but I think an error return is a useful diagnostic. Reviewed by: phk
* vfs_subr.c is getting rather fat. The underlying repocopy and thisphk2001-04-261-2852/+4
| | | | commit moves the filesystem export handling code to vfs_export.c
* Move the netexport structure from the fs-specific mountstructurephk2001-04-251-5/+61
| | | | | | | | | | | | | | to struct mount. This makes the "struct netexport *" paramter to the vfs_export and vfs_checkexport interface unneeded. Consequently that all non-stacking filesystems can use vfs_stdcheckexp(). At the same time, make it a pointer to a struct netexport in struct mount, so that we can remove the bogus AF_MAX and #include <net/radix.h> from <sys/mount.h>
* Correct #includes to work with fixed sys/mount.h.grog2001-04-231-0/+2
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* Reclaim directory vnodes held in namecache if few free vnodes aretanimura2001-04-181-0/+26
| | | | | | | | | | | | | | | available. Only directory vnodes holding no child directory vnodes held in v_cache_src are recycled, so that directory vnodes near the root of the filesystem hierarchy remain in namecache and directory vnodes are not reclaimed in cascade. The period of vnode reclaiming attempt and the number of vnodes attempted to reclaim can be tuned via sysctl(2). Suggested by: tegge Approved by: phk
* This patch removes the VOP_BWRITE() vector.phk2001-04-171-1/+1
| | | | | | | | | | | | | VOP_BWRITE() was a hack which made it possible for NFS client side to use struct buf with non-bio backing. This patch takes a more general approach and adds a bp->b_op vector where more methods can be added. The success of this patch depends on bp->b_op being initialized all relevant places for some value of "relevant" which is not easy to determine. For now the buffers have grown a b_magic element which will make such issues a tiny bit easier to debug.
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