/* * Copyright (c) 1990, 1992 Jan-Simon Pendry * All rights reserved. * * This code is derived from software contributed to Berkeley by * Jan-Simon Pendry. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $Id: kernfs_vnops.c,v 1.9 1993/05/28 16:47:05 cgd Exp $ */ /* * Kernel parameter filesystem */ #include "param.h" #include "systm.h" #include "kernel.h" #include "types.h" #include "time.h" #include "proc.h" #include "file.h" #include "vnode.h" #include "stat.h" #include "mount.h" #include "namei.h" #include "buf.h" #include "miscfs/kernfs/kernfs.h" #include "../ufs/dir.h" /* For readdir() XXX */ struct kernfs_target kernfs_targets[] = { /* NOTE: The name must be less than UIO_MX-16 chars in length */ DIR_TARGET(".", 0, KTT_NULL, KTM_DIR_PERMS ) DIR_TARGET("..", 0, KTT_NULL, KTM_DIR_PERMS ) REG_TARGET("copyright", copyright, KTT_STRING, KTM_RO_PERMS ) REG_TARGET("hostname", 0, KTT_HOSTNAME, KTM_RW_PERMS ) REG_TARGET("hz", &hz, KTT_INT, KTM_RO_PERMS ) REG_TARGET("loadavg", 0, KTT_AVENRUN, KTM_RO_PERMS ) REG_TARGET("physmem", &physmem, KTT_INT, KTM_RO_PERMS ) DIR_TARGET("root", 0, KTT_NULL, KTM_DIR_PERMS ) BLK_TARGET("rootdev", 0, KTT_NULL, KTM_RO_PERMS ) CHR_TARGET("rrootdev", 0, KTT_NULL, KTM_RO_PERMS ) REG_TARGET("time", 0, KTT_TIME, KTM_RO_PERMS ) REG_TARGET("version", version, KTT_STRING, KTM_RO_PERMS ) }; static int nkernfs_targets = sizeof(kernfs_targets) / sizeof(kernfs_targets[0]); static int kernfs_xread(kt, buf, len, lenp) struct kernfs_target *kt; char *buf; int len; int *lenp; { int xlen; switch (kt->kt_tag) { case KTT_TIME: { struct timeval tv; microtime(&tv); sprintf(buf, "%d %d\n", tv.tv_sec, tv.tv_usec); break; } case KTT_INT: { int *ip = kt->kt_data; sprintf(buf, "%d\n", *ip); break; } case KTT_STRING: { char *cp = kt->kt_data; int xlen = strlen(cp) + 1; if (xlen >= len) return (EINVAL); bcopy(cp, buf, xlen); break; } case KTT_HOSTNAME: { char *cp = hostname; int xlen = hostnamelen; if (xlen + 2 > len) /* extra space for null and newline */ return (EINVAL); bcopy(cp, buf, xlen); /* safer than sprintf */ buf[xlen] = '\n'; buf[xlen+1] = '\0'; break; } case KTT_AVENRUN: sprintf(buf, "%d %d %d %d\n", averunnable[0], averunnable[1], averunnable[2], FSCALE); break; default: return (EINVAL); } *lenp = strlen(buf); return (0); } static int kernfs_xwrite(kt, buf, len) struct kernfs_target *kt; char *buf; int len; { switch (kt->kt_tag) { case KTT_HOSTNAME: { if (buf[len-1] == '\n') --len; bcopy(buf, hostname, len); /* kernfs_write set buf[value_passed_as_len] = \0. * therefore, buf len (hostnamelen) = len. */ hostnamelen = len; hostname[hostnamelen] = '\0'; /* null end of string. */ return (0); } default: return (EIO); } } /* * vp is the current namei directory * ndp is the name to locate in that directory... */ kernfs_lookup(dvp, ndp, p) struct vnode *dvp; struct nameidata *ndp; struct proc *p; { char *pname = ndp->ni_ptr; int error = ENOENT; int i; struct vnode *fvp; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_lookup(%s)\n", pname); #endif if (ndp->ni_namelen == 1 && *pname == '.') { ndp->ni_dvp = dvp; ndp->ni_vp = dvp; VREF(dvp); /*VOP_LOCK(dvp);*/ return (0); } if (ndp->ni_namelen == 4 && bcmp(pname, "root", 4) == 0) { ndp->ni_dvp = dvp; ndp->ni_vp = rootdir; VREF(rootdir); VOP_LOCK(rootdir); return (0); } /* * /kern/rootdev is the root device */ if (ndp->ni_namelen == 7 && bcmp(pname, "rootdev", 7) == 0) { if (vfinddev(rootdev, VBLK, &fvp)) return (ENXIO); ndp->ni_dvp = dvp; ndp->ni_vp = fvp; VREF(fvp); VOP_LOCK(fvp); return (0); } /* * /kern/rrootdev is the root device */ if (ndp->ni_namelen == 8 && bcmp(pname, "rrootdev", 7) == 0) { ndp->ni_dvp = dvp; ndp->ni_vp = rrootdevvp; VREF(rrootdevvp); VOP_LOCK(rrootdevvp); return (0); } for (i = 0; i < nkernfs_targets; i++) { struct kernfs_target *kt = &kernfs_targets[i]; if (ndp->ni_namelen == strlen(kt->kt_name) && bcmp(kt->kt_name, pname, ndp->ni_namelen) == 0) { error = 0; break; } } #ifdef KERNFS_DIAGNOSTIC printf("kernfs_lookup: i = %d, error = %d\n", i, error); #endif if (error) goto bad; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_lookup: allocate new vnode\n"); #endif error = getnewvnode(VT_UFS, dvp->v_mount, &kernfs_vnodeops, &fvp); if (error) goto bad; VTOKERN(fvp)->kf_kt = &kernfs_targets[i]; fvp->v_type = VTOKERN(fvp)->kf_kt->kt_vtype; ndp->ni_dvp = dvp; ndp->ni_vp = fvp; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_lookup: newvp = %x\n", fvp); #endif return (0); bad:; ndp->ni_dvp = dvp; ndp->ni_vp = NULL; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_lookup: error = %d\n", error); #endif return (error); } kernfs_open(vp, mode, cred, p) struct vnode *vp; int mode; struct ucred *cred; struct proc *p; { /* if access succeeded, this always does, too */ return (0); } /* * Check mode permission on target pointer. Mode is READ, WRITE or EXEC. * The mode is shifted to select the owner/group/other fields. The * super user is granted all permissions. */ kernfs_access(vp, mode, cred, p) struct vnode *vp; register int mode; struct ucred *cred; struct proc *p; { struct kernfs_target *kt = VTOKERN(vp)->kf_kt; register gid_t *gp; int i, error; #ifdef KERN_DIAGNOSTIC if (!VOP_ISLOCKED(vp)) { vprint("kernfs_access: not locked", vp); panic("kernfs_access: not locked"); } #endif /* * If you're the super-user, you always get access. */ if (cred->cr_uid == 0) return (0); /* * Access check is based on only one of owner, group, public. * If not owner, then check group. If not a member of the * group, then check public access. */ if (cred->cr_uid != /* kt->kt_uid XXX */ 0) { mode >>= 3; gp = cred->cr_groups; for (i = 0; i < cred->cr_ngroups; i++, gp++) if (/* kt->kt_gid XXX */ 0 == *gp) goto found; mode >>= 3; found: ; } if ((kt->kt_perms & mode) == mode) return (0); return (EACCES); } kernfs_getattr(vp, vap, cred, p) struct vnode *vp; struct vattr *vap; struct ucred *cred; struct proc *p; { int error = 0; char strbuf[KSTRING]; struct kernfs_target *kt = VTOKERN(vp)->kf_kt; bzero((caddr_t) vap, sizeof(*vap)); vattr_null(vap); vap->va_uid = kt->kt_uid; vap->va_gid = kt->kt_gid; vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0]; /* vap->va_qsize = 0; */ vap->va_blocksize = DEV_BSIZE; microtime(&vap->va_atime); vap->va_mtime = vap->va_atime; vap->va_ctime = vap->va_ctime; vap->va_gen = 0; vap->va_flags = 0; vap->va_rdev = 0; /* vap->va_qbytes = 0; */ vap->va_bytes = 0; vap->va_type = kt->kt_vtype; vap->va_mode = kt->kt_perms; if (vp->v_flag & VROOT) { #ifdef KERNFS_DIAGNOSTIC printf("kernfs_getattr: stat rootdir\n"); #endif vap->va_nlink = 2; vap->va_fileid = 2; vap->va_size = DEV_BSIZE; } else { #ifdef KERNFS_DIAGNOSTIC printf("kernfs_getattr: stat target %s\n", kt->kt_name); #endif vap->va_nlink = 1; vap->va_fileid = 3 + (kt - kernfs_targets) / sizeof(*kt); error = kernfs_xread(kt, strbuf, sizeof(strbuf), &vap->va_size); } vp->v_type = vap->va_type; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_getattr: return error %d\n", error); #endif return (error); } /* * Change the mode on a file. */ kernfs_chmod1(vp, mode, p) register struct vnode *vp; register int mode; struct proc *p; { register struct ucred *cred = p->p_ucred; register struct kernfs_target *kt = VTOKERN(vp)->kf_kt; int error; if ((mode & kt->kt_maxperms) != mode) /* can't set ro var to rw */ return (EPERM); if (cred->cr_uid != kt->kt_uid && (error = suser(cred, &p->p_acflag))) return (error); if (cred->cr_uid) { if (vp->v_type != VDIR && (mode & S_ISVTX)) return (EFTYPE); if (!groupmember(kt->kt_gid, cred) && (mode & S_ISGID)) return (EPERM); } kt->kt_perms &= ~07777; kt->kt_perms |= mode & 07777; /* ip->i_flag |= ICHG;*/ return (0); } /* * Perform chown operation on kernfs_target kt */ kernfs_chown1(vp, uid, gid, p) register struct vnode *vp; uid_t uid; gid_t gid; struct proc *p; { register struct kernfs_target *kt = VTOKERN(vp)->kf_kt; register struct ucred *cred = p->p_ucred; uid_t ouid; gid_t ogid; int error = 0; if (uid == (u_short)VNOVAL) uid = kt->kt_uid; if (gid == (u_short)VNOVAL) gid = kt->kt_gid; /* * If we don't own the file, are trying to change the owner * of the file, or are not a member of the target group, * the caller must be superuser or the call fails. */ if ((cred->cr_uid != kt->kt_uid || uid != kt->kt_uid || !groupmember((gid_t)gid, cred)) && (error = suser(cred, &p->p_acflag))) return (error); ouid = kt->kt_uid; ogid = kt->kt_gid; kt->kt_uid = uid; kt->kt_gid = gid; /* if (ouid != uid || ogid != gid) ip->i_flag |= ICHG;*/ if (ouid != uid && cred->cr_uid != 0) kt->kt_perms &= ~S_ISUID; if (ogid != gid && cred->cr_uid != 0) kt->kt_perms &= ~S_ISGID; return (0); } /* * Set attribute vnode op. called from several syscalls */ kernfs_setattr(vp, vap, cred, p) struct vnode *vp; struct vattr *vap; struct ucred *cred; struct proc *p; { int error = 0; /* * Check for unsetable attributes. */ if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) || (vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) || (vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) || ((int)vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) { return (EINVAL); } /* * Go through the fields and update iff not VNOVAL. */ if (vap->va_uid != (u_short)VNOVAL || vap->va_gid != (u_short)VNOVAL) if (error = kernfs_chown1(vp, vap->va_uid, vap->va_gid, p)) return (error); if (vap->va_size != VNOVAL) { if (vp->v_type == VDIR) return (EISDIR); /* else just nod and smile... */ } if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) { /* if (cred->cr_uid != ip->i_uid && (error = suser(cred, &p->p_acflag))) return (error); if (vap->va_atime.tv_sec != VNOVAL) ip->i_flag |= IACC; if (vap->va_mtime.tv_sec != VNOVAL) ip->i_flag |= IUPD; ip->i_flag |= ICHG; if (error = iupdat(ip, &vap->va_atime, &vap->va_mtime, 1)) return (error); */ } if (vap->va_mode != (u_short)VNOVAL) error = kernfs_chmod1(vp, (int)vap->va_mode, p); if (vap->va_flags != VNOVAL) { /* if (cred->cr_uid != ip->i_uid && (error = suser(cred, &p->p_acflag))) return (error); if (cred->cr_uid == 0) { ip->i_flags = vap->va_flags; } else { ip->i_flags &= 0xffff0000; ip->i_flags |= (vap->va_flags & 0xffff); } ip->i_flag |= ICHG; */ } return (error); } static int kernfs_read(vp, uio, ioflag, cred) struct vnode *vp; struct uio *uio; int ioflag; struct ucred *cred; { struct kernfs_target *kt = VTOKERN(vp)->kf_kt; char strbuf[KSTRING]; int off = uio->uio_offset; int len = 0; char *cp = strbuf; int error; #ifdef KERNFS_DIAGNOSTIC printf("kern_read %s\n", kt->kt_name); #endif error = kernfs_xread(kt, strbuf, sizeof(strbuf), &len); if (error) return (error); cp = strbuf + off; len -= off; return (uiomove(cp, len, uio)); } static int kernfs_write(vp, uio, ioflag, cred) struct vnode *vp; struct uio *uio; int ioflag; struct ucred *cred; { struct kernfs_target *kt = VTOKERN(vp)->kf_kt; char strbuf[KSTRING]; int len = uio->uio_resid; char *cp = strbuf; int xlen; int error; if (uio->uio_offset != 0) return (EINVAL); xlen = min(uio->uio_resid, KSTRING-1); error = uiomove(strbuf, xlen, uio); if (error) return (error); if (uio->uio_resid != 0) return (EIO); strbuf[xlen] = '\0'; return (kernfs_xwrite(kt, strbuf, xlen)); } kernfs_readdir(vp, uio, cred, eofflagp) struct vnode *vp; struct uio *uio; struct ucred *cred; int *eofflagp; { struct filedesc *fdp; int i; int error; i = uio->uio_offset / UIO_MX; error = 0; while (uio->uio_resid > 0) { #ifdef KERNFS_DIAGNOSTIC printf("kernfs_readdir: i = %d\n", i); #endif if (i >= nkernfs_targets) { *eofflagp = 1; break; } { struct direct d; struct direct *dp = &d; struct kernfs_target *kt = &kernfs_targets[i]; bzero((caddr_t) dp, UIO_MX); dp->d_namlen = strlen(kt->kt_name); bcopy(kt->kt_name, dp->d_name, dp->d_namlen+1); #ifdef KERNFS_DIAGNOSTIC printf("kernfs_readdir: name = %s, len = %d\n", dp->d_name, dp->d_namlen); #endif /* * Fill in the remaining fields */ dp->d_reclen = UIO_MX; dp->d_ino = i + 3; /* * And ship to userland */ error = uiomove((caddr_t) dp, UIO_MX, uio); if (error) break; } i++; } uio->uio_offset = i * UIO_MX; return (error); } kernfs_inactive(vp, p) struct vnode *vp; struct proc *p; { /* * Clear out the v_type field to avoid * nasty things happening in vgone(). */ vp->v_type = VNON; #ifdef KERNFS_DIAGNOSTIC printf("kernfs_inactive(%x)\n", vp); #endif return (0); } /* * Print out the contents of a kernfs vnode. */ /* ARGSUSED */ kernfs_print(vp) struct vnode *vp; { printf("tag VT_NON, kernfs vnode\n"); } /* * kernfs vnode unsupported operation */ kernfs_enotsupp() { return (EOPNOTSUPP); } /* * kernfs "should never get here" operation */ kernfs_badop() { panic("kernfs: bad op"); /* NOTREACHED */ } /* * kernfs vnode null operation */ kernfs_nullop() { return (0); } #define kernfs_create ((int (*) __P(( \ struct nameidata *ndp, \ struct vattr *vap, \ struct proc *p))) kernfs_enotsupp) #define kernfs_mknod ((int (*) __P(( \ struct nameidata *ndp, \ struct vattr *vap, \ struct ucred *cred, \ struct proc *p))) kernfs_enotsupp) #define kernfs_close ((int (*) __P(( \ struct vnode *vp, \ int fflag, \ struct ucred *cred, \ struct proc *p))) nullop) #define kernfs_ioctl ((int (*) __P(( \ struct vnode *vp, \ int command, \ caddr_t data, \ int fflag, \ struct ucred *cred, \ struct proc *p))) kernfs_enotsupp) #define kernfs_select ((int (*) __P(( \ struct vnode *vp, \ int which, \ int fflags, \ struct ucred *cred, \ struct proc *p))) kernfs_enotsupp) #define kernfs_mmap ((int (*) __P(( \ struct vnode *vp, \ int fflags, \ struct ucred *cred, \ struct proc *p))) kernfs_enotsupp) #define kernfs_fsync ((int (*) __P(( \ struct vnode *vp, \ int fflags, \ struct ucred *cred, \ int waitfor, \ struct proc *p))) nullop) #define kernfs_seek ((int (*) __P(( \ struct vnode *vp, \ off_t oldoff, \ off_t newoff, \ struct ucred *cred))) nullop) #define kernfs_remove ((int (*) __P(( \ struct nameidata *ndp, \ struct proc *p))) kernfs_enotsupp) #define kernfs_link ((int (*) __P(( \ struct vnode *vp, \ struct nameidata *ndp, \ struct proc *p))) kernfs_enotsupp) #define kernfs_rename ((int (*) __P(( \ struct nameidata *fndp, \ struct nameidata *tdnp, \ struct proc *p))) kernfs_enotsupp) #define kernfs_mkdir ((int (*) __P(( \ struct nameidata *ndp, \ struct vattr *vap, \ struct proc *p))) kernfs_enotsupp) #define kernfs_rmdir ((int (*) __P(( \ struct nameidata *ndp, \ struct proc *p))) kernfs_enotsupp) #define kernfs_symlink ((int (*) __P(( \ struct nameidata *ndp, \ struct vattr *vap, \ char *target, \ struct proc *p))) kernfs_enotsupp) #define kernfs_readlink ((int (*) __P(( \ struct vnode *vp, \ struct uio *uio, \ struct ucred *cred))) kernfs_enotsupp) #define kernfs_abortop ((int (*) __P(( \ struct nameidata *ndp))) nullop) #ifdef KERNFS_DIAGNOSTIC int kernfs_reclaim(vp) struct vnode *vp; { printf("kernfs_reclaim(%x)\n", vp); return (0); } #else #define kernfs_reclaim ((int (*) __P(( \ struct vnode *vp))) nullop) #endif #define kernfs_lock ((int (*) __P(( \ struct vnode *vp))) nullop) #define kernfs_unlock ((int (*) __P(( \ struct vnode *vp))) nullop) #define kernfs_bmap ((int (*) __P(( \ struct vnode *vp, \ daddr_t bn, \ struct vnode **vpp, \ daddr_t *bnp))) kernfs_badop) #define kernfs_strategy ((int (*) __P(( \ struct buf *bp))) kernfs_badop) #define kernfs_islocked ((int (*) __P(( \ struct vnode *vp))) nullop) #define kernfs_advlock ((int (*) __P(( \ struct vnode *vp, \ caddr_t id, \ int op, \ struct flock *fl, \ int flags))) kernfs_enotsupp) struct vnodeops kernfs_vnodeops = { kernfs_lookup, /* lookup */ kernfs_create, /* create */ kernfs_mknod, /* mknod */ kernfs_open, /* open */ kernfs_close, /* close */ kernfs_access, /* access */ kernfs_getattr, /* getattr */ kernfs_setattr, /* setattr */ kernfs_read, /* read */ kernfs_write, /* write */ kernfs_ioctl, /* ioctl */ kernfs_select, /* select */ kernfs_mmap, /* mmap */ kernfs_fsync, /* fsync */ kernfs_seek, /* seek */ kernfs_remove, /* remove */ kernfs_link, /* link */ kernfs_rename, /* rename */ kernfs_mkdir, /* mkdir */ kernfs_rmdir, /* rmdir */ kernfs_symlink, /* symlink */ kernfs_readdir, /* readdir */ kernfs_readlink, /* readlink */ kernfs_abortop, /* abortop */ kernfs_inactive, /* inactive */ kernfs_reclaim, /* reclaim */ kernfs_lock, /* lock */ kernfs_unlock, /* unlock */ kernfs_bmap, /* bmap */ kernfs_strategy, /* strategy */ kernfs_print, /* print */ kernfs_islocked, /* islocked */ kernfs_advlock, /* advlock */ };