/* Copyright (C) 1995, 1989, 1998 Transarc Corporation - All rights reserved */ /* * (C) COPYRIGHT IBM CORPORATION 1987, 1988 * LICENSED MATERIALS - PROPERTY OF IBM */ /* * afs_vnop_access.c - access vop ccess mode bit support for vnode operations. * * Implements: * afs_GetAccessBits * afs_AccessOK * afs_access * * Local: * fileModeMap (table) */ #include "../afs/param.h" /* Should be always first */ #include "../afs/sysincludes.h" /* Standard vendor system headers */ #include "../afs/afsincludes.h" /* Afs-based standard headers */ #include "../afs/afs_stats.h" /* statistics */ #include "../afs/afs_cbqueue.h" #include "../afs/nfsclient.h" #include "../afs/afs_osidnlc.h" #ifndef ANONYMOUSID #define ANONYMOUSID 32766 /* make sure this is same as in ptserver.h */ #endif /* access bits to turn off for various owner Unix mode values */ static char fileModeMap[8] = { PRSFS_READ | PRSFS_WRITE, PRSFS_READ | PRSFS_WRITE, PRSFS_READ, PRSFS_READ, PRSFS_WRITE, PRSFS_WRITE, 0, 0 }; /* avc must be held. Returns bit map of mode bits. Ignores file mode bits */ afs_int32 afs_GetAccessBits (avc, arights, areq) register struct vcache *avc; register afs_int32 arights; register struct vrequest *areq; { AFS_STATCNT(afs_GetAccessBits); /* see if anyuser has the required access bits */ if ((arights & avc->anyAccess) == arights) { return arights; } /* look in per-pag cache */ if (avc->Access) { /* not beautiful, but Sun's cc will tolerate it */ struct axscache *ac; ac = afs_FindAxs(avc->Access, areq->uid); if (ac) { return (arights & ac->axess); } } if (!(avc->states & CForeign)) { /* If there aren't any bits cached for this user (but the vnode * _is_ cached, obviously), make sure this user has valid tokens * before bothering with the RPC. */ struct unixuser *tu; extern struct unixuser *afs_FindUser(); tu = afs_FindUser( areq->uid, avc->fid.Cell, READ_LOCK ); if (!tu) { return (arights & avc->anyAccess); } if ((tu->vid == UNDEFVID) || !(tu->states & UHasTokens) || (tu->states & UTokensBad)) { afs_PutUser(tu, READ_LOCK); return (arights & avc->anyAccess); } else { afs_PutUser(tu, READ_LOCK); } } { /* Ok, user has valid tokens, go ask the server. */ struct AFSFetchStatus OutStatus; afs_int32 code; code = afs_FetchStatus(avc, &avc->fid, areq, &OutStatus); return (code ? 0 : OutStatus.CallerAccess & arights); } } /* the new access ok function. AVC must be held but not locked. if avc is a * file, its parent need not be held, and should not be locked. */ afs_AccessOK(avc, arights, areq, check_mode_bits) struct vcache *avc; afs_int32 arights, check_mode_bits; struct vrequest *areq; { register struct vcache *tvc; struct VenusFid dirFid; register afs_int32 mask; afs_int32 dirBits; register afs_int32 fileBits; AFS_STATCNT(afs_AccessOK); if ((vType(avc) == VDIR) || (avc->states & CForeign)) { /* rights are just those from acl */ return (arights == afs_GetAccessBits(avc, arights, areq)); } else { /* some rights come from dir and some from file. Specifically, you * have "a" rights to a file if you are its owner, which comes * back as "a" rights to the file. You have other rights just * from dir, but all are restricted by the file mode bit. Now, * if you have I and A rights to a file, we throw in R and W * rights for free. These rights will then be restricted by * the access mask. */ dirBits = 0; if (avc->parentVnode) { dirFid.Cell = avc->fid.Cell; dirFid.Fid.Volume = avc->fid.Fid.Volume; dirFid.Fid.Vnode = avc->parentVnode; dirFid.Fid.Unique = avc->parentUnique; /* Avoid this GetVCache call */ tvc = afs_GetVCache(&dirFid, areq, (afs_int32 *)0, (struct vcache*)0, WRITE_LOCK); if (tvc) { dirBits = afs_GetAccessBits(tvc, arights, areq); afs_PutVCache(tvc, WRITE_LOCK); } } else dirBits = 0xffffffff; /* assume OK; this is a race condition */ if (arights & PRSFS_ADMINISTER) fileBits = afs_GetAccessBits(avc, arights, areq); else fileBits = 0; /* don't make call if results don't matter */ /* compute basic rights in fileBits, taking A from file bits */ fileBits = (fileBits & PRSFS_ADMINISTER) | (dirBits & ~PRSFS_ADMINISTER); /* for files, throw in R and W if have I and A (owner). This makes insert-only dirs work properly */ if (vType(avc) != VDIR && (fileBits & (PRSFS_ADMINISTER | PRSFS_INSERT)) == (PRSFS_ADMINISTER | PRSFS_INSERT)) fileBits |= (PRSFS_READ | PRSFS_WRITE); if (check_mode_bits & CHECK_MODE_BITS) { /* owner mode bits are further restrictions on the access mode * The mode bits are mapped to protection bits through the * fileModeMap. If CMB_ALLOW_EXEC_AS_READ is set, it's from the * NFS translator and we don't know if it's a read or execute * on the NFS client, but both need to read the data. */ mask = (avc->m.Mode & 0700) >> 6; /* file restrictions to use */ fileBits &= ~fileModeMap[mask]; if (check_mode_bits & CMB_ALLOW_EXEC_AS_READ) { if (avc->m.Mode & 0100) fileBits |= PRSFS_READ; } } return ((fileBits & arights) == arights); /* true if all rights bits are on */ } } #if defined(AFS_SUN5_ENV) || (defined(AFS_SGI_ENV) && !defined(AFS_SGI65_ENV)) afs_access(OSI_VC_ARG(avc), amode, flags, acred) int flags; #else afs_access(OSI_VC_ARG(avc), amode, acred) #endif OSI_VC_DECL(avc); register afs_int32 amode; struct AFS_UCRED *acred; { register afs_int32 code; struct vrequest treq; OSI_VC_CONVERT(avc) AFS_STATCNT(afs_access); afs_Trace3(afs_iclSetp, CM_TRACE_ACCESS, ICL_TYPE_POINTER, avc, ICL_TYPE_INT32, amode, ICL_TYPE_INT32, avc->m.Length); if (code = afs_InitReq(&treq, acred)) return code; code = afs_VerifyVCache(avc, &treq); if (code) { code = afs_CheckCode(code, &treq, 16); return code; } /* if we're looking for write access and we have a read-only file system, report it */ if ((amode & VWRITE) && (avc->states & CRO)) { return EROFS; } code = 1; /* Default from here on in is access ok. */ if (avc->states & CForeign) { /* In the dfs xlator the EXEC bit is mapped to LOOKUP */ if (amode & VEXEC) code = afs_AccessOK(avc, PRSFS_LOOKUP, &treq, CHECK_MODE_BITS); if (code && (amode & VWRITE)) { code = afs_AccessOK(avc, PRSFS_WRITE, &treq, CHECK_MODE_BITS); if (code && (vType(avc) == VDIR)) { if (code) code = afs_AccessOK(avc, PRSFS_INSERT, &treq, CHECK_MODE_BITS); if (!code) code = afs_AccessOK(avc, PRSFS_DELETE, &treq, CHECK_MODE_BITS); } } if (code && (amode & VREAD)) code = afs_AccessOK(avc, PRSFS_READ, &treq, CHECK_MODE_BITS); } else { if (vType(avc) == VDIR) { if (amode & VEXEC) code = afs_AccessOK(avc, PRSFS_LOOKUP, &treq, CHECK_MODE_BITS); if (code && (amode & VWRITE)) { code = afs_AccessOK(avc, PRSFS_INSERT, &treq, CHECK_MODE_BITS); if (!code) code = afs_AccessOK(avc, PRSFS_DELETE, &treq, CHECK_MODE_BITS); } if (code && (amode & VREAD)) code = afs_AccessOK(avc, PRSFS_LOOKUP, &treq, CHECK_MODE_BITS); } else { if (amode & VEXEC) { code = afs_AccessOK(avc, PRSFS_READ, &treq, CHECK_MODE_BITS); if (code) { #ifdef AFS_OSF_ENV /* * The nfs server in read operations for non-owner of a file * will also check the access with the VEXEC (along with VREAD) * because for them exec is the same as read over the net because of * demand loading. But this means if the mode bit is '-rw' the call * will fail below; so for this particular case where both modes are * specified (only in rfs_read so far) and from the xlator requests * we return succes. */ if (!((amode & VREAD) && AFS_NFSXLATORREQ(acred))) #endif if ((avc->m.Mode & 0100) == 0) code = 0; } else if (avc->m.Mode & 0100) code = 1; } if (code && (amode & VWRITE)) { code = afs_AccessOK(avc, PRSFS_WRITE, &treq, CHECK_MODE_BITS); /* The above call fails when the NFS translator tries to copy ** a file with r--r--r-- permissions into a directory which ** has system:anyuser acl. This is because the destination file ** file is first created with r--r--r-- permissions through an ** unauthenticated connectin. hence, the above afs_AccessOK ** call returns failure. hence, we retry without any file ** mode bit checking */ if ( !code && AFS_NFSXLATORREQ(acred) && avc->m.Owner == ANONYMOUSID) code=afs_AccessOK(avc,PRSFS_WRITE, &treq, DONT_CHECK_MODE_BITS); } if (code && (amode & VREAD)) code = afs_AccessOK(avc, PRSFS_READ, &treq, CHECK_MODE_BITS); } } if (code) return 0; /* if access is ok */ else { code = afs_CheckCode(EACCES, &treq, 17); /* failure code */ return code; } }