/*      $OpenBSD: fstat.c,v 1.104 2025/12/12 06:33:18 tb Exp $  */

/*
 * Copyright (c) 2009 Todd C. Miller <millert@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*-
 * Copyright (c) 1988, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * 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. 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.
 */

#include <sys/types.h>
#include <sys/queue.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/vnode.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/eventvar.h>
#include <sys/sysctl.h>
#include <sys/filedesc.h>
#define _KERNEL /* for DTYPE_* */
#include <sys/file.h>
#undef _KERNEL

#include <net/route.h>
#include <netinet/in.h>

#include <netdb.h>
#include <arpa/inet.h>

#include <sys/pipe.h>

#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <kvm.h>
#include <limits.h>
#include <nlist.h>
#include <pwd.h>
#include <search.h>
#include <signal.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <err.h>

#include "fstat.h"

#define MAXIMUM(a, b)   (((a) > (b)) ? (a) : (b))

struct fstat_filter {
        int what;
        int arg;
};

struct fileargs fileargs = SLIST_HEAD_INITIALIZER(fileargs);

int     fsflg;  /* show files on same filesystem as file(s) argument */
int     uflg;   /* show files open by a particular (effective) user */
int     checkfile; /* true if restricting to particular files or filesystems */
int     nflg;   /* (numerical) display f.s. and rdev as dev_t */
int     oflg;   /* display file offset */
int     sflg;   /* display file xfer/bytes counters */
int     vflg;   /* display errors in locating kernel data objects etc... */
int     cflg;   /* fuser only */

int     fuser;  /* 1 if we are fuser, 0 if we are fstat */
int     signo;  /* signal to send (fuser only) */

int     nfilter = 0;    /* How many uid/pid filters are in place */
struct fstat_filter *filter = NULL; /* An array of uid/pid filters */

kvm_t *kd;
uid_t uid;

void fstat_dofile(struct kinfo_file *);
void fstat_header(void);
void getinetproto(int);
__dead void usage(void);
int getfname(char *);
void kqueuetrans(struct kinfo_file *);
void pipetrans(struct kinfo_file *);
struct kinfo_file *splice_find(char, u_int64_t);
void splice_insert(char, u_int64_t, struct kinfo_file *);
void find_splices(struct kinfo_file *, int);
void print_inet_details(struct kinfo_file *);
void print_inet6_details(struct kinfo_file *);
void print_sock_details(struct kinfo_file *);
void socktrans(struct kinfo_file *);
void vtrans(struct kinfo_file *);
const char *inet6_addrstr(struct in6_addr *);
int signame_to_signum(char *);
void hide(void *p);

int hideroot;

void
hide(void *p)
{
        printf("%p", hideroot ? NULL : p);
}

int
main(int argc, char *argv[])
{
        struct kinfo_file *kf, *kflast;
        int ch;
        char *memf, *nlistf, *optstr;
        char buf[_POSIX2_LINE_MAX];
        const char *errstr;
        int cnt, flags;

        hideroot = getuid();

        nlistf = memf = NULL;
        oflg = 0;

        /* are we fstat(1) or fuser(1)? */
        if (strcmp(__progname, "fuser") == 0) {
                fuser = 1;
                optstr = "cfks:uM:N:";
        } else {
                fuser = 0;
                optstr = "fnop:su:vN:M:";
        }

        /*
         * fuser and fstat share three flags: -f, -s and -u.  In both cases
         * -f is a boolean, but for -u fstat wants an argument while fuser
         * does not and for -s fuser wants an argument whereas fstat does not.
         */
        while ((ch = getopt(argc, argv, optstr)) != -1)
                switch ((char)ch) {
                case 'c':
                        if (fsflg)
                                usage();
                        cflg = 1;
                        break;
                case 'f':
                        if (cflg)
                                usage();
                        fsflg = 1;
                        break;
                case 'k':
                        sflg = 1;
                        signo = SIGKILL;
                        break;
                case 'M':
                        memf = optarg;
                        break;
                case 'N':
                        nlistf = optarg;
                        break;
                case 'n':
                        nflg = 1;
                        break;
                case 'o':
                        oflg = 1;
                        break;
                case 'p':
                        if ((filter = recallocarray(filter, nfilter, nfilter + 1,
                            sizeof(*filter))) == NULL)
                                err(1, NULL);
                        filter[nfilter].arg = strtonum(optarg, 0, INT_MAX,
                            &errstr);
                        if (errstr != NULL) {
                                warnx("-p requires a process id, %s: %s",
                                        errstr, optarg);
                                usage();
                        }
                        filter[nfilter].what = KERN_FILE_BYPID;
                        nfilter++;
                        break;
                case 's':
                        sflg = 1;
                        if (fuser) {
                                signo = signame_to_signum(optarg);
                                if (signo == -1) {
                                        warnx("invalid signal %s", optarg);
                                        usage();
                                }
                        }
                        break;
                case 'u':
                        uflg = 1;
                        if (!fuser) {
                                uid_t uid;

                                if (uid_from_user(optarg, &uid) == -1) {
                                        uid = strtonum(optarg, 0, UID_MAX,
                                            &errstr);
                                        if (errstr != NULL) {
                                                errx(1, "%s: unknown uid",
                                                    optarg);
                                        }
                                }
                                if ((filter = recallocarray(filter, nfilter,
                                    nfilter + 1, sizeof(*filter))) == NULL)
                                        err(1, NULL);
                                filter[nfilter].arg = uid;
                                filter[nfilter].what = KERN_FILE_BYUID;
                                nfilter++;
                        }
                        break;
                case 'v':
                        vflg = 1;
                        break;
                default:
                        usage();
                }

        /*
         * get the uid, for oflg and sflg
         */
        uid = getuid();

        /*
         * Use sysctl unless inspecting an alternate kernel.
         */
        if (nlistf == NULL || memf == NULL)
                flags = KVM_NO_FILES;
        else
                flags = O_RDONLY;

        if ((kd = kvm_openfiles(nlistf, memf, NULL, flags, buf)) == NULL)
                errx(1, "%s", buf);

        if (*(argv += optind)) {
                for (; *argv; ++argv) {
                        if (getfname(*argv))
                                checkfile = 1;
                }
                /* file(s) specified, but none accessible */
                if (!checkfile)
                        exit(1);
        } else if (fuser)
                usage();

        if (!fuser && fsflg && !checkfile) {
                /* fstat -f with no files means use wd */
                if (getfname(".") == 0)
                        exit(1);
                checkfile = 1;
        }

        if (nfilter == 1) {
                if ((kf = kvm_getfiles(kd, filter[0].what, filter[0].arg,
                    sizeof(*kf), &cnt)) == NULL)
                        errx(1, "%s", kvm_geterr(kd));
        } else {
                if ((kf = kvm_getfiles(kd, KERN_FILE_BYPID, -1, sizeof(*kf),
                    &cnt)) == NULL)
                        errx(1, "%s", kvm_geterr(kd));
        }

        if (fuser) {
                /*
                 * fuser
                 *  uflg: need "getpw"
                 *  sflg: need "proc" (might call kill(2))
                 */
                if (uflg && sflg) {
                        if (pledge("stdio rpath getpw proc", NULL) == -1)
                                err(1, "pledge");
                } else if (uflg) {
                        if (pledge("stdio rpath getpw", NULL) == -1)
                                err(1, "pledge");
                } else if (sflg) {
                        if (pledge("stdio rpath proc", NULL) == -1)
                                err(1, "pledge");
                } else {
                        if (pledge("stdio rpath", NULL) == -1)
                                err(1, "pledge");
                }
        } else {
                /* fstat */
                if (pledge("stdio rpath getpw", NULL) == -1)
                        err(1, "pledge");
        }

        find_splices(kf, cnt);
        if (!fuser)
                fstat_header();
        for (kflast = &kf[cnt]; kf < kflast; ++kf) {
                if (fuser)
                        fuser_check(kf);
                else
                        fstat_dofile(kf);
        }
        if (fuser)
                fuser_run();

        exit(0);
}

void
fstat_header(void)
{
        if (nflg)
                printf("%s",
"USER     CMD          PID   FD  DEV      INUM        MODE    R/W    SZ|DV");
        else
                printf("%s",
"USER     CMD          PID   FD MOUNT        INUM  MODE          R/W    SZ|DV");
        if (oflg)
                printf("%s", ":OFFSET  ");
        if (checkfile && fsflg == 0)
                printf(" NAME");
        if (sflg)
                printf("    XFERS   KBYTES");
        putchar('\n');
}

const char *Uname, *Comm;
uid_t   *procuid;
pid_t   Pid;

#define PREFIX(i) do { \
        printf("%-8.8s %-10s %5ld", Uname, Comm, (long)Pid); \
        switch (i) { \
        case KERN_FILE_TEXT: \
                printf(" text"); \
                break; \
        case KERN_FILE_CDIR: \
                printf("   wd"); \
                break; \
        case KERN_FILE_RDIR: \
                printf(" root"); \
                break; \
        case KERN_FILE_TRACE: \
                printf("   tr"); \
                break; \
        default: \
                printf(" %4d", i); \
                break; \
        } \
} while (0)

/*
 * print open files attributed to this process
 */
void
fstat_dofile(struct kinfo_file *kf)
{
        int i;

        Uname = user_from_uid(kf->p_uid, 0);
        procuid = &kf->p_uid;
        Pid = kf->p_pid;
        Comm = kf->p_comm;

        for (i = 0; i < nfilter; i++) {
                if (filter[i].what == KERN_FILE_BYPID) {
                        if (filter[i].arg == Pid)
                                break;
                } else if (filter[i].arg == *procuid) {
                        break;
                }
        }
        if (i == nfilter && nfilter != 0)
                return;

        switch (kf->f_type) {
        case DTYPE_VNODE:
                vtrans(kf);
                break;
        case DTYPE_SOCKET:
                socktrans(kf);
                break;
        case DTYPE_PIPE:
                if (checkfile == 0)
                        pipetrans(kf);
                break;
        case DTYPE_KQUEUE:
                if (checkfile == 0)
                        kqueuetrans(kf);
                break;
        default:
                if (vflg) {
                        warnx("unknown file type %d for file %d of pid %ld",
                            kf->f_type, kf->fd_fd, (long)Pid);
                }
                break;
        }
}

void
vtrans(struct kinfo_file *kf)
{
        const char *badtype = NULL;
        char rwep[6], mode[12];
        char *filename = NULL;

        if (kf->v_type == VNON)
                badtype = "none";
        else if (kf->v_type == VBAD)
                badtype = "bad";
        else if (kf->v_tag == VT_NON && !(kf->v_flag & VCLONE))
                badtype = "none";       /* not a clone */

        if (checkfile) {
                int fsmatch = 0;
                struct filearg *fa;

                if (badtype)
                        return;
                SLIST_FOREACH(fa, &fileargs, next) {
                        if (fa->dev == kf->va_fsid) {
                                fsmatch = 1;
                                if (fa->ino == kf->va_fileid) {
                                        filename = fa->name;
                                        break;
                                }
                        }
                }
                if (fsmatch == 0 || (filename == NULL && fsflg == 0))
                        return;
        }
        PREFIX(kf->fd_fd);
        if (badtype) {
                (void)printf(" -           -  %10s    -\n", badtype);
                return;
        }

        if (nflg)
                (void)printf(" %2lu,%-2lu", (long)major(kf->va_fsid),
                    (long)minor(kf->va_fsid));
        else if (!(kf->v_flag & VCLONE))
                (void)printf(" %-8s", kf->f_mntonname);
        else
                (void)printf(" clone   ");
        if (nflg)
                (void)snprintf(mode, sizeof(mode), "%o", kf->va_mode);
        else
                strmode(kf->va_mode, mode);
        printf(" %8llu%s %11s", kf->va_fileid,
            kf->va_nlink == 0 ? "*" : " ",
            mode);
        rwep[0] = '\0';
        if (kf->f_flag & FREAD)
                strlcat(rwep, "r", sizeof rwep);
        if (kf->f_flag & FWRITE)
                strlcat(rwep, "w", sizeof rwep);
        if (kf->fd_ofileflags & UF_EXCLOSE)
                strlcat(rwep, "e", sizeof rwep);
        if (kf->fd_ofileflags & UF_FORKCLOSE)
                strlcat(rwep, "f", sizeof rwep);
        if (kf->fd_ofileflags & UF_PLEDGED)
                strlcat(rwep, "p", sizeof rwep);
        printf(" %5s", rwep);
        switch (kf->v_type) {
        case VBLK:
        case VCHR: {
                char *name;

                if (nflg || ((name = devname(kf->va_rdev,
                    kf->v_type == VCHR ?  S_IFCHR : S_IFBLK)) == NULL))
                        printf("   %2u,%-3u", major(kf->va_rdev), minor(kf->va_rdev));
                else
                        printf("  %7s", name);
                if (oflg)
                        printf("         ");
                break;
        }
        default:
                printf(" %8llu", kf->va_size);
                if (oflg) {
                        if (uid == 0 || uid == *procuid)
                                printf(":%-8llu", kf->f_offset);
                        else
                                printf(":%-8s", "*");
                }
        }
        if (sflg) {
                if (uid == 0 || uid == *procuid) {
                        printf(" %8llu %8llu",
                            (kf->f_rxfer + kf->f_rwfer),
                            (kf->f_rbytes + kf->f_wbytes) / 1024);
                } else {
                        printf(" %8s %8s", "*", "*");
                }
        }
        if (filename && !fsflg)
                printf(" %s", filename);
        putchar('\n');
}

void
pipetrans(struct kinfo_file *kf)
{
        void *maxaddr;

        PREFIX(kf->fd_fd);

        printf(" ");

        /*
         * We don't have enough space to fit both peer and own address, so
         * we select the higher address so both ends of the pipe have the
         * same visible addr. (it's the higher address because when the other
         * end closes, it becomes 0)
         */
        maxaddr = (void *)(uintptr_t)MAXIMUM(kf->f_data, kf->pipe_peer);

        printf("pipe ");
        hide(maxaddr);
        printf(" state: %s%s%s",
            (kf->pipe_state & PIPE_WANTR) ? "R" : "",
            (kf->pipe_state & PIPE_WANTW) ? "W" : "",
            (kf->pipe_state & PIPE_EOF) ? "E" : "");
        if (sflg)
                printf("\t%8llu %8llu",
                    (kf->f_rxfer + kf->f_rwfer),
                    (kf->f_rbytes + kf->f_wbytes) / 1024);
        printf("\n");
        return;
}

void
kqueuetrans(struct kinfo_file *kf)
{
        PREFIX(kf->fd_fd);

        printf(" ");

        printf("kqueue ");
        hide((void *)(uintptr_t)kf->f_data);
        printf(" %d state: %s\n",
            kf->kq_count,
            (kf->kq_state & KQ_SLEEP) ? "W" : "");
        return;
}

const char *
inet6_addrstr(struct in6_addr *p)
{
        struct sockaddr_in6 sin6;
        static char hbuf[NI_MAXHOST];
        const int niflags = NI_NUMERICHOST;

        memset(&sin6, 0, sizeof(sin6));
        sin6.sin6_family = AF_INET6;
        sin6.sin6_len = sizeof(struct sockaddr_in6);
        sin6.sin6_addr = *p;
        if (IN6_IS_ADDR_LINKLOCAL(p) &&
            *(u_int16_t *)&sin6.sin6_addr.s6_addr[2] != 0) {
                sin6.sin6_scope_id =
                    ntohs(*(u_int16_t *)&sin6.sin6_addr.s6_addr[2]);
                sin6.sin6_addr.s6_addr[2] = sin6.sin6_addr.s6_addr[3] = 0;
        }

        if (getnameinfo((struct sockaddr *)&sin6, sin6.sin6_len,
            hbuf, sizeof(hbuf), NULL, 0, niflags))
                return "invalid";

        return hbuf;
}

void
splice_insert(char type, u_int64_t ptr, struct kinfo_file *data)
{
        ENTRY entry, *found;

        if (asprintf(&entry.key, "%c%llx", type, hideroot ? 0 : ptr) == -1)
                err(1, NULL);
        entry.data = data;
        if ((found = hsearch(entry, ENTER)) == NULL)
                err(1, "hsearch");
        /* if it's ambiguous, set the data to NULL */
        if (found->data != data)
                found->data = NULL;
}

struct kinfo_file *
splice_find(char type, u_int64_t ptr)
{
        ENTRY entry, *found;
        char buf[20];

        snprintf(buf, sizeof(buf), "%c%llx", type, hideroot ? 0 : ptr);
        entry.key = buf;
        found = hsearch(entry, FIND);
        return (found != NULL ? found->data : NULL);
}

void
find_splices(struct kinfo_file *kf, int cnt)
{
        int i, created;

        created = 0;
        for (i = 0; i < cnt; i++) {
                if (kf[i].f_type != DTYPE_SOCKET ||
                    (kf[i].so_splice == 0 && kf[i].so_splicelen != -1))
                        continue;
                if (created++ == 0) {
                        if (hcreate(1000) == 0)
                                err(1, "hcreate");
                }
                splice_insert('>', kf[i].f_data, &kf[i]);
                if (kf[i].so_splice != 0)
                        splice_insert('<', kf[i].so_splice, &kf[i]);
        }
}

void
print_inet_details(struct kinfo_file *kf)
{
        struct in_addr laddr, faddr;

        memcpy(&laddr, kf->inp_laddru, sizeof(laddr));
        memcpy(&faddr, kf->inp_faddru, sizeof(faddr));
        if (kf->so_protocol == IPPROTO_TCP) {
                printf(" ");
                hide((void *)(uintptr_t)kf->inp_ppcb);
                printf(" %s:%d", laddr.s_addr == INADDR_ANY ? "*" :
                    inet_ntoa(laddr), ntohs(kf->inp_lport));
                if (kf->inp_fport) {
                        if (kf->so_state & SS_CONNECTOUT)
                                printf(" --> ");
                        else
                                printf(" <-- ");
                        printf("%s:%d",
                            faddr.s_addr == INADDR_ANY ? "*" :
                            inet_ntoa(faddr), ntohs(kf->inp_fport));
                }
        } else if (kf->so_protocol == IPPROTO_UDP) {
                printf(" %s:%d", laddr.s_addr == INADDR_ANY ? "*" :
                    inet_ntoa(laddr), ntohs(kf->inp_lport));
                if (kf->inp_fport) {
                        printf(" <-> %s:%d",
                            faddr.s_addr == INADDR_ANY ? "*" :
                            inet_ntoa(faddr), ntohs(kf->inp_fport));
                }
        } else if (kf->so_pcb) {
                printf(" ");
                hide((void *)(uintptr_t)kf->so_pcb);
        }
}

void
print_inet6_details(struct kinfo_file *kf)
{
        char xaddrbuf[NI_MAXHOST + 2];
        struct in6_addr laddr6, faddr6;

        memcpy(&laddr6, kf->inp_laddru, sizeof(laddr6));
        memcpy(&faddr6, kf->inp_faddru, sizeof(faddr6));
        if (kf->so_protocol == IPPROTO_TCP) {
                printf(" ");
                hide((void *)(uintptr_t)kf->inp_ppcb);
                snprintf(xaddrbuf, sizeof(xaddrbuf), "[%s]",
                    inet6_addrstr(&laddr6));
                printf(" %s:%d",
                    IN6_IS_ADDR_UNSPECIFIED(&laddr6) ? "*" :
                    xaddrbuf, ntohs(kf->inp_lport));
                if (kf->inp_fport) {
                        if (kf->so_state & SS_CONNECTOUT)
                                printf(" --> ");
                        else
                                printf(" <-- ");
                        snprintf(xaddrbuf, sizeof(xaddrbuf), "[%s]",
                            inet6_addrstr(&faddr6));
                        printf("%s:%d",
                            IN6_IS_ADDR_UNSPECIFIED(&faddr6) ? "*" :
                            xaddrbuf, ntohs(kf->inp_fport));
                }
        } else if (kf->so_protocol == IPPROTO_UDP) {
                snprintf(xaddrbuf, sizeof(xaddrbuf), "[%s]",
                    inet6_addrstr(&laddr6));
                printf(" %s:%d",
                    IN6_IS_ADDR_UNSPECIFIED(&laddr6) ? "*" :
                    xaddrbuf, ntohs(kf->inp_lport));
                if (kf->inp_fport) {
                        snprintf(xaddrbuf, sizeof(xaddrbuf), "[%s]",
                            inet6_addrstr(&faddr6));
                        printf(" <-> %s:%d",
                            IN6_IS_ADDR_UNSPECIFIED(&faddr6) ? "*" :
                            xaddrbuf, ntohs(kf->inp_fport));
                }
        } else if (kf->so_pcb) {
                printf(" ");
                hide((void *)(uintptr_t)kf->so_pcb);
        }
}

void
print_sock_details(struct kinfo_file *kf)
{
        if (kf->so_family == AF_INET)
                print_inet_details(kf);
        else if (kf->so_family == AF_INET6)
                print_inet6_details(kf);
}

void
socktrans(struct kinfo_file *kf)
{
        static char *stypename[] = {
                "unused",       /* 0 */
                "stream",       /* 1 */
                "dgram",        /* 2 */
                "raw",          /* 3 */
                "rdm",          /* 4 */
                "seqpak"        /* 5 */
        };
#define STYPEMAX 5
        char *stype, stypebuf[24];

        if (checkfile) {
                struct filearg *fa;

                if (kf->so_type != AF_UNIX)
                        return;
                SLIST_FOREACH(fa, &fileargs, next) {
                        if (fa->dev != 0)
                                continue;
                        if (strcmp(kf->unp_path, fa->name) == 0)
                                break;
                }
                if (fa == NULL)
                        return;
        }

        PREFIX(kf->fd_fd);

        if (kf->so_type > STYPEMAX) {
                snprintf(stypebuf, sizeof(stypebuf), "?%d", kf->so_type);
                stype = stypebuf;
        } else {
                stype = stypename[kf->so_type];
        }

        /*
         * protocol specific formatting
         *
         * Try to find interesting things to print.  For tcp, the interesting
         * thing is the address of the tcpcb, for udp and others, just the
         * inpcb (socket pcb).  For unix domain, its the address of the socket
         * pcb and the address of the connected pcb (if connected).  Otherwise
         * just print the protocol number and address of the socket itself.
         * The idea is not to duplicate netstat, but to make available enough
         * information for further analysis.
         */
        switch (kf->so_family) {
        case AF_INET:
                printf("* internet %s", stype);
                getinetproto(kf->so_protocol);
                print_inet_details(kf);
                if (kf->inp_rtableid)
                        printf(" rtable %u", kf->inp_rtableid);
                break;
        case AF_INET6:
                printf("* internet6 %s", stype);
                getinetproto(kf->so_protocol);
                print_inet6_details(kf);
                if (kf->inp_rtableid)
                        printf(" rtable %u", kf->inp_rtableid);
                break;
        case AF_UNIX:
                /* print address of pcb and connected pcb */
                printf("* unix %s", stype);
                if (kf->so_pcb) {
                        printf(" ");
                        hide((void *)(uintptr_t)kf->so_pcb);
                        if (kf->unp_conn) {
                                char shoconn[4], *cp;

                                cp = shoconn;
                                if (!(kf->so_state & SS_CANTRCVMORE))
                                        *cp++ = '<';
                                *cp++ = '-';
                                if (!(kf->so_state & SS_CANTSENDMORE))
                                        *cp++ = '>';
                                *cp = '\0';
                                printf(" %s ", shoconn);
                                hide((void *)(uintptr_t)kf->unp_conn);
                        }
                }
                if (kf->unp_path[0] != '\0')
                        printf(" %s", kf->unp_path);
                break;
        case AF_MPLS:
                /* print protocol number and socket address */
                printf("* mpls %s", stype);
                printf(" %d ", kf->so_protocol);
                hide((void *)(uintptr_t)kf->f_data);
                break;
        case AF_ROUTE:
                /* print protocol number and socket address */
                printf("* route %s", stype);
                printf(" %d ", kf->so_protocol);
                hide((void *)(uintptr_t)kf->f_data);
                break;
        case AF_KEY:
                printf("* pfkey %s", stype);
                printf(" %d ", kf->so_protocol);
                hide((void *)(uintptr_t)kf->f_data);
                break;
        default:
                /* print protocol number and socket address */
                printf("* %d %s", kf->so_family, stype);
                printf(" %d ", kf->so_protocol);
                hide((void *)(uintptr_t)kf->f_data);
        }
        if (kf->so_splice != 0 || kf->so_splicelen == -1) {
                struct kinfo_file *from, *to;

                from = splice_find('<', kf->f_data);
                to = NULL;
                if (kf->so_splice != 0)
                        to = splice_find('>', kf->so_splice);

                if (to != NULL && from == to) {
                        printf(" <==>");
                        print_sock_details(to);
                } else if (kf->so_splice != 0) {
                        printf(" ==>");
                        if (to != NULL)
                                print_sock_details(to);
                } else if (kf->so_splicelen == -1) {
                        printf(" <==");
                        if (from != NULL)
                                print_sock_details(from);
                }
        }
        if (sflg)
                printf("\t%8llu %8llu",
                    (kf->f_rxfer + kf->f_rwfer),
                    (kf->f_rbytes + kf->f_wbytes) / 1024);
        printf("\n");
}

/*
 * getinetproto --
 *      print name of protocol number
 */
void
getinetproto(int number)
{
        static int isopen;
        struct protoent *pe;

        if (!isopen)
                setprotoent(++isopen);
        if ((pe = getprotobynumber(number)) != NULL)
                printf(" %s", pe->p_name);
        else
                printf(" %d", number);
}

int
getfname(char *filename)
{
        static struct statfs *mntbuf;
        static int nmounts;
        int i;
        struct stat sb;
        struct filearg *cur;

        if (stat(filename, &sb)) {
                warn("%s", filename);
                return (0);
        }

        /*
         * POSIX specifies "For block special devices, all processes using any
         * file on that device are listed".  However the -f flag description
         * states "The report shall be only for the named files", so we only
         * look up a block device if the -f flag has not be specified.
         */
        if (fuser && !fsflg && S_ISBLK(sb.st_mode)) {
                if (mntbuf == NULL) {
                        nmounts = getmntinfo(&mntbuf, MNT_NOWAIT);
                        if (nmounts == -1)
                                err(1, "getmntinfo");
                }
                for (i = 0; i < nmounts; i++) {
                        if (!strcmp(mntbuf[i].f_mntfromname, filename)) {
                                if (stat(mntbuf[i].f_mntonname, &sb) == -1) {
                                        warn("%s", filename);
                                        return (0);
                                }
                                cflg = 1;
                                break;
                        }
                }
        }
        if (!fuser && S_ISSOCK(sb.st_mode)) {
                char *newname = realpath(filename, NULL);
                if (newname != NULL)
                        filename = newname;
        }

        if ((cur = calloc(1, sizeof(*cur))) == NULL)
                err(1, NULL);

        if (!S_ISSOCK(sb.st_mode)) {
                cur->ino = sb.st_ino;
                cur->dev = sb.st_dev & 0xffff;
        }
        cur->name = filename;
        TAILQ_INIT(&cur->fusers);
        SLIST_INSERT_HEAD(&fileargs, cur, next);
        return (1);
}

int
signame_to_signum(char *sig)
{
        int n;
        const char *errstr = NULL;

        if (isdigit((unsigned char)*sig)) {
                n = strtonum(sig, 0, NSIG - 1, &errstr);
                return (errstr ? -1 : n);
        }
        if (!strncasecmp(sig, "sig", 3))
                sig += 3;
        for (n = 1; n < NSIG; n++) {
                if (!strcasecmp(sys_signame[n], sig))
                        return (n);
        }
        return (-1);
}

void
usage(void)
{
        if (fuser) {
                fprintf(stderr, "usage: fuser [-cfku] [-M core] "
                    "[-N system] [-s signal] file ...\n");
        } else {
                fprintf(stderr, "usage: fstat [-fnosv] [-M core] [-N system] "
                    "[-p pid] [-u user] [file ...]\n");
        }
        exit(1);
}