/* * Copyright (c) 2000 Dag-Erling Coïdan Smørgrav * Copyright (c) 1999 Pierre Beyssac * Copyright (c) 1993, 1995 Jan-Simon Pendry * Copyright (c) 1993, 1995 * The Regents of the University of California. 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. * * @(#)procfs_vnops.c 8.18 (Berkeley) 5/21/95 * * $FreeBSD$ */ /* * procfs vnode interface */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern struct vnode *procfs_findtextvp __P((struct proc *)); extern int procfs_kmemaccess __P((struct proc *)); static int linprocfs_access __P((struct vop_access_args *)); static int linprocfs_badop __P((void)); static int linprocfs_bmap __P((struct vop_bmap_args *)); static int linprocfs_close __P((struct vop_close_args *)); static int linprocfs_getattr __P((struct vop_getattr_args *)); static int linprocfs_inactive __P((struct vop_inactive_args *)); static int linprocfs_ioctl __P((struct vop_ioctl_args *)); static int linprocfs_lookup __P((struct vop_lookup_args *)); static int linprocfs_open __P((struct vop_open_args *)); static int linprocfs_print __P((struct vop_print_args *)); static int linprocfs_readdir __P((struct vop_readdir_args *)); static int linprocfs_readlink __P((struct vop_readlink_args *)); static int linprocfs_reclaim __P((struct vop_reclaim_args *)); static int linprocfs_setattr __P((struct vop_setattr_args *)); /* * This is a list of the valid names in the * process-specific sub-directories. It is * used in linprocfs_lookup and linprocfs_readdir */ static struct proc_target { u_char pt_type; u_char pt_namlen; char *pt_name; pfstype pt_pfstype; int (*pt_valid) __P((struct proc *p)); } proc_targets[] = { #define N(s) sizeof(s)-1, s /* name type validp */ { DT_DIR, N("."), Pproc, NULL }, { DT_DIR, N(".."), Proot, NULL }, { DT_REG, N("cmdline"), Pcmdline, NULL }, { DT_LNK, N("exe"), Pexe, NULL }, { DT_REG, N("mem"), Pmem, NULL }, { DT_REG, N("stat"), Pprocstat, NULL }, { DT_REG, N("status"), Pprocstatus, NULL }, #undef N }; static const int nproc_targets = sizeof(proc_targets) / sizeof(proc_targets[0]); static pid_t atopid __P((const char *, u_int)); /* * set things up for doing i/o on * the pfsnode (vp). (vp) is locked * on entry, and should be left locked * on exit. * * for procfs we don't need to do anything * in particular for i/o. all that is done * is to support exclusive open on process * memory images. */ static int linprocfs_open(ap) struct vop_open_args /* { struct vnode *a_vp; int a_mode; struct ucred *a_cred; struct proc *a_p; } */ *ap; { struct pfsnode *pfs = VTOPFS(ap->a_vp); struct proc *p1, *p2; p2 = PFIND(pfs->pfs_pid); if (p2 == NULL) return (ENOENT); if (pfs->pfs_pid && p_can(ap->a_p, p2, P_CAN_SEE, NULL)) return (ENOENT); switch (pfs->pfs_type) { case Pmem: if (((pfs->pfs_flags & FWRITE) && (ap->a_mode & O_EXCL)) || ((pfs->pfs_flags & O_EXCL) && (ap->a_mode & FWRITE))) return (EBUSY); p1 = ap->a_p; if (p_can(p1, p2, P_CAN_DEBUG, NULL) && !procfs_kmemaccess(p1)) return (EPERM); if (ap->a_mode & FWRITE) pfs->pfs_flags = ap->a_mode & (FWRITE|O_EXCL); return (0); default: break; } return (0); } /* * close the pfsnode (vp) after doing i/o. * (vp) is not locked on entry or exit. * * nothing to do for procfs other than undo * any exclusive open flag (see _open above). */ static int linprocfs_close(ap) struct vop_close_args /* { struct vnode *a_vp; int a_fflag; struct ucred *a_cred; struct proc *a_p; } */ *ap; { struct pfsnode *pfs = VTOPFS(ap->a_vp); struct proc *p; switch (pfs->pfs_type) { case Pmem: if ((ap->a_fflag & FWRITE) && (pfs->pfs_flags & O_EXCL)) pfs->pfs_flags &= ~(FWRITE|O_EXCL); /* * If this is the last close, then it checks to see if * the target process has PF_LINGER set in p_pfsflags, * if this is *not* the case, then the process' stop flags * are cleared, and the process is woken up. This is * to help prevent the case where a process has been * told to stop on an event, but then the requesting process * has gone away or forgotten about it. */ if ((ap->a_vp->v_usecount < 2) && (p = pfind(pfs->pfs_pid)) && !(p->p_pfsflags & PF_LINGER)) { p->p_stops = 0; p->p_step = 0; wakeup(&p->p_step); } break; default: break; } return (0); } /* * do an ioctl operation on a pfsnode (vp). * (vp) is not locked on entry or exit. */ static int linprocfs_ioctl(ap) struct vop_ioctl_args *ap; { struct pfsnode *pfs = VTOPFS(ap->a_vp); struct proc *procp, *p; int error; int signo; struct procfs_status *psp; unsigned char flags; p = ap->a_p; procp = pfind(pfs->pfs_pid); if (procp == NULL) return ENOTTY; if ((error = p_can(p, procp, P_CAN_DEBUG, NULL))) return (error == ESRCH ? ENOENT : error); switch (ap->a_command) { case PIOCBIS: procp->p_stops |= *(unsigned int*)ap->a_data; break; case PIOCBIC: procp->p_stops &= ~*(unsigned int*)ap->a_data; break; case PIOCSFL: /* * NFLAGS is "non-suser_xxx flags" -- currently, only * PFS_ISUGID ("ignore set u/g id"); */ #define NFLAGS (PF_ISUGID) flags = (unsigned char)*(unsigned int*)ap->a_data; if (flags & NFLAGS && (error = suser(p))) return error; procp->p_pfsflags = flags; break; case PIOCGFL: *(unsigned int*)ap->a_data = (unsigned int)procp->p_pfsflags; case PIOCSTATUS: psp = (struct procfs_status *)ap->a_data; psp->state = (procp->p_step == 0); psp->flags = procp->p_pfsflags; psp->events = procp->p_stops; if (procp->p_step) { psp->why = procp->p_stype; psp->val = procp->p_xstat; } else { psp->why = psp->val = 0; /* Not defined values */ } break; case PIOCWAIT: psp = (struct procfs_status *)ap->a_data; if (procp->p_step == 0) { error = tsleep(&procp->p_stype, PWAIT | PCATCH, "piocwait", 0); if (error) return error; } psp->state = 1; /* It stopped */ psp->flags = procp->p_pfsflags; psp->events = procp->p_stops; psp->why = procp->p_stype; /* why it stopped */ psp->val = procp->p_xstat; /* any extra info */ break; case PIOCCONT: /* Restart a proc */ if (procp->p_step == 0) return EINVAL; /* Can only start a stopped process */ if ((signo = *(int*)ap->a_data) != 0) { if (signo >= NSIG || signo <= 0) return EINVAL; psignal(procp, signo); } procp->p_step = 0; wakeup(&procp->p_step); break; default: return (ENOTTY); } return 0; } /* * do block mapping for pfsnode (vp). * since we don't use the buffer cache * for procfs this function should never * be called. in any case, it's not clear * what part of the kernel ever makes use * of this function. for sanity, this is the * usual no-op bmap, although returning * (EIO) would be a reasonable alternative. */ static int linprocfs_bmap(ap) struct vop_bmap_args /* { struct vnode *a_vp; daddr_t a_bn; struct vnode **a_vpp; daddr_t *a_bnp; int *a_runp; } */ *ap; { if (ap->a_vpp != NULL) *ap->a_vpp = ap->a_vp; if (ap->a_bnp != NULL) *ap->a_bnp = ap->a_bn; if (ap->a_runp != NULL) *ap->a_runp = 0; return (0); } /* * linprocfs_inactive is called when the pfsnode * is vrele'd and the reference count goes * to zero. (vp) will be on the vnode free * list, so to get it back vget() must be * used. * * (vp) is locked on entry, but must be unlocked on exit. */ static int linprocfs_inactive(ap) struct vop_inactive_args /* { struct vnode *a_vp; } */ *ap; { struct vnode *vp = ap->a_vp; VOP_UNLOCK(vp, 0, ap->a_p); return (0); } /* * _reclaim is called when getnewvnode() * wants to make use of an entry on the vnode * free list. at this time the filesystem needs * to free any private data and remove the node * from any private lists. */ static int linprocfs_reclaim(ap) struct vop_reclaim_args /* { struct vnode *a_vp; } */ *ap; { return (linprocfs_freevp(ap->a_vp)); } /* * _print is used for debugging. * just print a readable description * of (vp). */ static int linprocfs_print(ap) struct vop_print_args /* { struct vnode *a_vp; } */ *ap; { struct pfsnode *pfs = VTOPFS(ap->a_vp); printf("tag VT_PROCFS, type %d, pid %ld, mode %x, flags %lx\n", pfs->pfs_type, (long)pfs->pfs_pid, pfs->pfs_mode, pfs->pfs_flags); return (0); } /* * generic entry point for unsupported operations */ static int linprocfs_badop() { return (EIO); } /* * Invent attributes for pfsnode (vp) and store * them in (vap). * Directories lengths are returned as zero since * any real length would require the genuine size * to be computed, and nothing cares anyway. * * this is relatively minimal for procfs. */ static int linprocfs_getattr(ap) struct vop_getattr_args /* { struct vnode *a_vp; struct vattr *a_vap; struct ucred *a_cred; struct proc *a_p; } */ *ap; { struct pfsnode *pfs = VTOPFS(ap->a_vp); struct vattr *vap = ap->a_vap; struct proc *procp; int error; /* * First make sure that the process and its credentials * still exist. */ switch (pfs->pfs_type) { case Proot: case Pself: procp = 0; break; default: procp = PFIND(pfs->pfs_pid); if (procp == 0 || procp->p_cred == NULL || procp->p_ucred == NULL) return (ENOENT); if (p_can(ap->a_p, procp, P_CAN_SEE, NULL)) return (ENOENT); } error = 0; /* start by zeroing out the attributes */ VATTR_NULL(vap); /* next do all the common fields */ vap->va_type = ap->a_vp->v_type; vap->va_mode = pfs->pfs_mode; vap->va_fileid = pfs->pfs_fileno; vap->va_flags = 0; vap->va_blocksize = PAGE_SIZE; vap->va_bytes = vap->va_size = 0; vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0]; /* * Make all times be current TOD. * It would be possible to get the process start * time from the p_stat structure, but there's * no "file creation" time stamp anyway, and the * p_stat structure is not addressible if u. gets * swapped out for that process. */ nanotime(&vap->va_ctime); vap->va_atime = vap->va_mtime = vap->va_ctime; /* * If the process has exercised some setuid or setgid * privilege, then rip away read/write permission so * that only root can gain access. */ switch (pfs->pfs_type) { case Pmem: /* Retain group kmem readablity. */ if (procp->p_flag & P_SUGID) vap->va_mode &= ~(VREAD|VWRITE); break; default: break; } /* * now do the object specific fields * * The size could be set from struct reg, but it's hardly * worth the trouble, and it puts some (potentially) machine * dependent data into this machine-independent code. If it * becomes important then this function should break out into * a per-file stat function in the corresponding .c file. */ vap->va_nlink = 1; if (procp) { vap->va_uid = procp->p_ucred->cr_uid; vap->va_gid = procp->p_ucred->cr_gid; } switch (pfs->pfs_type) { case Proot: /* * Set nlink to 1 to tell fts(3) we don't actually know. */ vap->va_nlink = 1; vap->va_uid = 0; vap->va_gid = 0; vap->va_size = vap->va_bytes = DEV_BSIZE; break; case Pself: { char buf[16]; /* should be enough */ vap->va_uid = 0; vap->va_gid = 0; vap->va_size = vap->va_bytes = snprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid); break; } case Pproc: vap->va_nlink = nproc_targets; vap->va_size = vap->va_bytes = DEV_BSIZE; break; case Pexe: { char *fullpath, *freepath; error = textvp_fullpath(procp, &fullpath, &freepath); if (error == 0) { vap->va_size = strlen(fullpath); free(freepath, M_TEMP); } else { vap->va_size = sizeof("unknown") - 1; error = 0; } vap->va_bytes = vap->va_size; break; } case Pmeminfo: case Pcpuinfo: case Pstat: case Puptime: case Pversion: vap->va_bytes = vap->va_size = 0; vap->va_uid = 0; vap->va_gid = 0; break; case Pmem: /* * If we denied owner access earlier, then we have to * change the owner to root - otherwise 'ps' and friends * will break even though they are setgid kmem. *SIGH* */ if (procp->p_flag & P_SUGID) vap->va_uid = 0; else vap->va_uid = procp->p_ucred->cr_uid; vap->va_gid = KMEM_GROUP; break; case Pcmdline: case Pprocstat: case Pprocstatus: vap->va_bytes = vap->va_size = 0; /* uid, gid are already set */ break; default: panic("linprocfs_getattr"); } return (error); } static int linprocfs_setattr(ap) struct vop_setattr_args /* { struct vnode *a_vp; struct vattr *a_vap; struct ucred *a_cred; struct proc *a_p; } */ *ap; { if (ap->a_vap->va_flags != VNOVAL) return (EOPNOTSUPP); /* * just fake out attribute setting * it's not good to generate an error * return, otherwise things like creat() * will fail when they try to set the * file length to 0. worse, this means * that echo $note > /proc/$pid/note will fail. */ return (0); } /* * implement access checking. * * actually, the check for super-user is slightly * broken since it will allow read access to write-only * objects. this doesn't cause any particular trouble * but does mean that the i/o entry points need to check * that the operation really does make sense. */ static int linprocfs_access(ap) struct vop_access_args /* { struct vnode *a_vp; int a_mode; struct ucred *a_cred; struct proc *a_p; } */ *ap; { struct pfsnode *pfs = VTOPFS(ap->a_vp); struct vnode *vp = ap->a_vp; struct proc *procp; struct vattr *vap; struct vattr vattr; int error; switch (pfs->pfs_type) { case Proot: case Pself: case Pmeminfo: case Pcpuinfo: case Pstat: case Puptime: case Pversion: break; default: procp = PFIND(pfs->pfs_pid); if (procp == NULL) return (ENOENT); if (p_can(ap->a_p, procp, P_CAN_SEE, NULL)) return (ENOENT); } vap = &vattr; error = VOP_GETATTR(vp, vap, ap->a_cred, ap->a_p); if (error) return (error); return (vaccess(vp->v_type, vap->va_mode, vap->va_uid, vap->va_gid, ap->a_mode, ap->a_cred, NULL)); } /* * lookup. this is incredibly complicated in the * general case, however for most pseudo-filesystems * very little needs to be done. * * unless you want to get a migraine, just make sure your * filesystem doesn't do any locking of its own. otherwise * read and inwardly digest ufs_lookup(). */ static int linprocfs_lookup(ap) struct vop_lookup_args /* { struct vnode * a_dvp; struct vnode ** a_vpp; struct componentname * a_cnp; } */ *ap; { struct componentname *cnp = ap->a_cnp; struct proc *curp = cnp->cn_proc; struct vnode **vpp = ap->a_vpp; struct vnode *dvp = ap->a_dvp; char *pname = cnp->cn_nameptr; struct proc_target *pt; pid_t pid; struct pfsnode *pfs; struct proc *p; int i; *vpp = NULL; if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME || cnp->cn_nameiop == CREATE) return (EROFS); if (cnp->cn_namelen == 1 && *pname == '.') { *vpp = dvp; VREF(dvp); /* vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, curp); */ return (0); } pfs = VTOPFS(dvp); switch (pfs->pfs_type) { case Proot: if (cnp->cn_flags & ISDOTDOT) return (EIO); if (CNEQ(cnp, "self", 4)) return (linprocfs_allocvp(dvp->v_mount, vpp, 0, Pself)); if (CNEQ(cnp, "meminfo", 7)) return (linprocfs_allocvp(dvp->v_mount, vpp, 0, Pmeminfo)); if (CNEQ(cnp, "cpuinfo", 7)) return (linprocfs_allocvp(dvp->v_mount, vpp, 0, Pcpuinfo)); if (CNEQ(cnp, "stat", 4)) return (linprocfs_allocvp(dvp->v_mount, vpp, 0, Pstat)); if (CNEQ(cnp, "uptime", 6)) return (linprocfs_allocvp(dvp->v_mount, vpp, 0, Puptime)); if (CNEQ(cnp, "version", 7)) return (linprocfs_allocvp(dvp->v_mount, vpp, 0, Pversion)); pid = atopid(pname, cnp->cn_namelen); if (pid == NO_PID) break; p = PFIND(pid); if (p == 0) break; if (p_can(curp, p, P_CAN_SEE, NULL)) break; return (linprocfs_allocvp(dvp->v_mount, vpp, pid, Pproc)); case Pproc: if (cnp->cn_flags & ISDOTDOT) return (linprocfs_root(dvp->v_mount, vpp)); p = PFIND(pfs->pfs_pid); if (p == 0) break; for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) { if (cnp->cn_namelen == pt->pt_namlen && bcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 && (pt->pt_valid == NULL || (*pt->pt_valid)(p))) goto found; } break; found: return (linprocfs_allocvp(dvp->v_mount, vpp, pfs->pfs_pid, pt->pt_pfstype)); default: return (ENOTDIR); } return (cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS); } /* * Does this process have a text file? */ int linprocfs_validfile(p) struct proc *p; { return (procfs_findtextvp(p) != NULLVP); } /* * readdir() returns directory entries from pfsnode (vp). * * We generate just one directory entry at a time, as it would probably * not pay off to buffer several entries locally to save uiomove calls. */ static int linprocfs_readdir(ap) struct vop_readdir_args /* { struct vnode *a_vp; struct uio *a_uio; struct ucred *a_cred; int *a_eofflag; int *a_ncookies; u_long **a_cookies; } */ *ap; { struct uio *uio = ap->a_uio; struct dirent d; struct dirent *dp = &d; struct pfsnode *pfs; int count, error, i, off; static u_int delen; if (!delen) { d.d_namlen = PROCFS_NAMELEN; delen = GENERIC_DIRSIZ(&d); } pfs = VTOPFS(ap->a_vp); off = (int)uio->uio_offset; if (off != uio->uio_offset || off < 0 || off % delen != 0 || uio->uio_resid < delen) return (EINVAL); error = 0; count = 0; i = off / delen; switch (pfs->pfs_type) { /* * this is for the process-specific sub-directories. * all that is needed to is copy out all the entries * from the procent[] table (top of this file). */ case Pproc: { struct proc *p; struct proc_target *pt; p = PFIND(pfs->pfs_pid); if (p == NULL) break; if (p_can(curproc, p, P_CAN_SEE, NULL)) break; for (pt = &proc_targets[i]; uio->uio_resid >= delen && i < nproc_targets; pt++, i++) { if (pt->pt_valid && (*pt->pt_valid)(p) == 0) continue; dp->d_reclen = delen; dp->d_fileno = PROCFS_FILENO(pfs->pfs_pid, pt->pt_pfstype); dp->d_namlen = pt->pt_namlen; bcopy(pt->pt_name, dp->d_name, pt->pt_namlen + 1); dp->d_type = pt->pt_type; if ((error = uiomove((caddr_t)dp, delen, uio)) != 0) break; } break; } /* * this is for the root of the procfs filesystem * what is needed is a special entry for "self" * followed by an entry for each process on allproc #ifdef PROCFS_ZOMBIE * and zombproc. #endif */ case Proot: { #ifdef PROCFS_ZOMBIE int doingzomb = 0; #endif int pcnt = 0; struct proc *p; ALLPROC_LOCK(AP_SHARED); p = allproc.lh_first; for (; p && uio->uio_resid >= delen; i++, pcnt++) { bzero((char *) dp, delen); dp->d_reclen = delen; switch (i) { case 0: /* `.' */ case 1: /* `..' */ dp->d_fileno = PROCFS_FILENO(0, Proot); dp->d_namlen = i + 1; bcopy("..", dp->d_name, dp->d_namlen); dp->d_name[i + 1] = '\0'; dp->d_type = DT_DIR; break; case 2: dp->d_fileno = PROCFS_FILENO(0, Pself); dp->d_namlen = 4; bcopy("self", dp->d_name, 5); dp->d_type = DT_LNK; break; case 3: dp->d_fileno = PROCFS_FILENO(0, Pmeminfo); dp->d_namlen = 7; bcopy("meminfo", dp->d_name, 8); dp->d_type = DT_REG; break; case 4: dp->d_fileno = PROCFS_FILENO(0, Pcpuinfo); dp->d_namlen = 7; bcopy("cpuinfo", dp->d_name, 8); dp->d_type = DT_REG; break; case 5: dp->d_fileno = PROCFS_FILENO(0, Pstat); dp->d_namlen = 4; bcopy("stat", dp->d_name, 5); dp->d_type = DT_REG; break; case 6: dp->d_fileno = PROCFS_FILENO(0, Puptime); dp->d_namlen = 6; bcopy("uptime", dp->d_name, 7); dp->d_type = DT_REG; break; case 7: dp->d_fileno = PROCFS_FILENO(0, Pversion); dp->d_namlen = 7; bcopy("version", dp->d_name, 8); dp->d_type = DT_REG; break; default: while (pcnt < i) { p = p->p_list.le_next; if (!p) goto done; if (p_can(curproc, p, P_CAN_SEE, NULL)) continue; pcnt++; } while (p_can(curproc, p, P_CAN_SEE, NULL)) { p = p->p_list.le_next; if (!p) goto done; } dp->d_fileno = PROCFS_FILENO(p->p_pid, Pproc); dp->d_namlen = sprintf(dp->d_name, "%ld", (long)p->p_pid); dp->d_type = DT_DIR; p = p->p_list.le_next; break; } if ((error = uiomove((caddr_t)dp, delen, uio)) != 0) break; } done: #ifdef PROCFS_ZOMBIE if (p == 0 && doingzomb == 0) { doingzomb = 1; p = zombproc.lh_first; goto again; } #endif ALLPROC_LOCK(AP_RELEASE); break; } default: error = ENOTDIR; break; } uio->uio_offset = i * delen; return (error); } /* * readlink reads the link of `self' or `exe' */ static int linprocfs_readlink(ap) struct vop_readlink_args *ap; { char buf[16]; /* should be enough */ struct proc *procp; struct vnode *vp = ap->a_vp; struct pfsnode *pfs = VTOPFS(vp); char *fullpath, *freepath; int error, len; switch (pfs->pfs_type) { case Pself: if (pfs->pfs_fileno != PROCFS_FILENO(0, Pself)) return (EINVAL); len = snprintf(buf, sizeof(buf), "%ld", (long)curproc->p_pid); return (uiomove(buf, len, ap->a_uio)); /* * There _should_ be no way for an entire process to disappear * from under us... */ case Pexe: procp = PFIND(pfs->pfs_pid); if (procp == NULL || procp->p_cred == NULL || procp->p_ucred == NULL) { printf("linprocfs_readlink: pid %d disappeared\n", pfs->pfs_pid); return (uiomove("unknown", sizeof("unknown") - 1, ap->a_uio)); } error = textvp_fullpath(procp, &fullpath, &freepath); if (error != 0) return (uiomove("unknown", sizeof("unknown") - 1, ap->a_uio)); error = uiomove(fullpath, strlen(fullpath), ap->a_uio); free(freepath, M_TEMP); return (error); default: return (EINVAL); } } /* * convert decimal ascii to pid_t */ static pid_t atopid(b, len) const char *b; u_int len; { pid_t p = 0; while (len--) { char c = *b++; if (c < '0' || c > '9') return (NO_PID); p = 10 * p + (c - '0'); if (p > PID_MAX) return (NO_PID); } return (p); } /* * procfs vnode operations. */ vop_t **linprocfs_vnodeop_p; static struct vnodeopv_entry_desc linprocfs_vnodeop_entries[] = { { &vop_default_desc, (vop_t *) vop_defaultop }, { &vop_access_desc, (vop_t *) linprocfs_access }, { &vop_advlock_desc, (vop_t *) linprocfs_badop }, { &vop_bmap_desc, (vop_t *) linprocfs_bmap }, { &vop_close_desc, (vop_t *) linprocfs_close }, { &vop_create_desc, (vop_t *) linprocfs_badop }, { &vop_getattr_desc, (vop_t *) linprocfs_getattr }, { &vop_inactive_desc, (vop_t *) linprocfs_inactive }, { &vop_link_desc, (vop_t *) linprocfs_badop }, { &vop_lookup_desc, (vop_t *) linprocfs_lookup }, { &vop_mkdir_desc, (vop_t *) linprocfs_badop }, { &vop_mknod_desc, (vop_t *) linprocfs_badop }, { &vop_open_desc, (vop_t *) linprocfs_open }, { &vop_pathconf_desc, (vop_t *) vop_stdpathconf }, { &vop_print_desc, (vop_t *) linprocfs_print }, { &vop_read_desc, (vop_t *) linprocfs_rw }, { &vop_readdir_desc, (vop_t *) linprocfs_readdir }, { &vop_readlink_desc, (vop_t *) linprocfs_readlink }, { &vop_reclaim_desc, (vop_t *) linprocfs_reclaim }, { &vop_remove_desc, (vop_t *) linprocfs_badop }, { &vop_rename_desc, (vop_t *) linprocfs_badop }, { &vop_rmdir_desc, (vop_t *) linprocfs_badop }, { &vop_setattr_desc, (vop_t *) linprocfs_setattr }, { &vop_symlink_desc, (vop_t *) linprocfs_badop }, { &vop_write_desc, (vop_t *) linprocfs_rw }, { &vop_ioctl_desc, (vop_t *) linprocfs_ioctl }, { NULL, NULL } }; static struct vnodeopv_desc linprocfs_vnodeop_opv_desc = { &linprocfs_vnodeop_p, linprocfs_vnodeop_entries }; VNODEOP_SET(linprocfs_vnodeop_opv_desc);