/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1983, 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/cdefs.h>
/*
 * Display protocol blocks in the unix domain.
 */
#include <sys/param.h>
#include <sys/queue.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#define _WANT_SOCKET
#include <sys/socketvar.h>
#include <sys/mbuf.h>
#include <sys/sysctl.h>
#include <sys/un.h>
#define _WANT_UNPCB
#include <sys/unpcb.h>

#include <netinet/in.h>

#include <errno.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <strings.h>
#include <kvm.h>
#include <libxo/xo.h>
#include "netstat.h"

static  void unixdomainpr(struct xunpcb *, struct xsocket *);

static  const char *const socktype[] =
    { "#0", "stream", "dgram", "raw", "rdm", "seqpacket" };

static int
pcblist_sysctl(int type, char **bufp)
{
        char    *buf;
        size_t  len;
        char mibvar[sizeof "net.local.seqpacket.pcblist"];

        snprintf(mibvar, sizeof(mibvar), "net.local.%s.pcblist", socktype[type]);

        len = 0;
        if (sysctlbyname(mibvar, 0, &len, 0, 0) < 0) {
                if (errno != ENOENT)
                        xo_warn("sysctl: %s", mibvar);
                return (-1);
        }
        if ((buf = malloc(len)) == NULL) {
                xo_warnx("malloc %lu bytes", (u_long)len);
                return (-2);
        }
        if (sysctlbyname(mibvar, buf, &len, 0, 0) < 0) {
                xo_warn("sysctl: %s", mibvar);
                free(buf);
                return (-2);
        }
        *bufp = buf;
        return (0);
}

static int
pcblist_kvm(u_long count_off, u_long gencnt_off, u_long head_off, char **bufp)
{
        struct unp_head head;
        struct unpcb *unp, unp0, unp_conn;
        u_char sun_len;
        struct socket so;
        struct xunpgen xug;
        struct xunpcb xu;
        unp_gen_t unp_gencnt;
        u_int   unp_count;
        char    *buf, *p;
        size_t  len;

        if (count_off == 0 || gencnt_off == 0)
                return (-2);
        if (head_off == 0)
                return (-1);
        kread(count_off, &unp_count, sizeof(unp_count));
        len = 2 * sizeof(xug) + (unp_count + unp_count / 8) * sizeof(xu);
        if ((buf = malloc(len)) == NULL) {
                xo_warnx("malloc %lu bytes", (u_long)len);
                return (-2);
        }
        p = buf;

#define COPYOUT(obj, size) do {                                         \
        if (len < (size)) {                                             \
                xo_warnx("buffer size exceeded");                       \
                goto fail;                                              \
        }                                                               \
        bcopy((obj), p, (size));                                        \
        len -= (size);                                                  \
        p += (size);                                                    \
} while (0)

#define KREAD(off, buf, len) do {                                       \
        if (kread((uintptr_t)(off), (buf), (len)) != 0)                 \
                goto fail;                                              \
} while (0)

        /* Write out header. */
        kread(gencnt_off, &unp_gencnt, sizeof(unp_gencnt));
        xug.xug_len = sizeof xug;
        xug.xug_count = unp_count;
        xug.xug_gen = unp_gencnt;
        xug.xug_sogen = 0;
        COPYOUT(&xug, sizeof xug);

        /* Walk the PCB list. */
        xu.xu_len = sizeof xu;
        KREAD(head_off, &head, sizeof(head));
        LIST_FOREACH(unp, &head, unp_link) {
                xu.xu_unpp = (uintptr_t)unp;
                KREAD(unp, &unp0, sizeof (*unp));
                unp = &unp0;

                if (unp->unp_gencnt > unp_gencnt)
                        continue;
                if (unp->unp_addr != NULL) {
                        KREAD(unp->unp_addr, &sun_len, sizeof(sun_len));
                        KREAD(unp->unp_addr, &xu.xu_addr, sun_len);
                }
                if (unp->unp_conn != NULL) {
                        KREAD(unp->unp_conn, &unp_conn, sizeof(unp_conn));
                        if (unp_conn.unp_addr != NULL) {
                                KREAD(unp_conn.unp_addr, &sun_len,
                                    sizeof(sun_len));
                                KREAD(unp_conn.unp_addr, &xu.xu_caddr, sun_len);
                        }
                }
                KREAD(unp->unp_socket, &so, sizeof(so));
                if (sotoxsocket(&so, &xu.xu_socket) != 0)
                        goto fail;
                COPYOUT(&xu, sizeof(xu));
        }

        /* Reread the counts and write the footer. */
        kread(count_off, &unp_count, sizeof(unp_count));
        kread(gencnt_off, &unp_gencnt, sizeof(unp_gencnt));
        xug.xug_count = unp_count;
        xug.xug_gen = unp_gencnt;
        COPYOUT(&xug, sizeof xug);

        *bufp = buf;
        return (0);

fail:
        free(buf);
        return (-1);
#undef COPYOUT
#undef KREAD
}

void
unixpr(u_long count_off, u_long gencnt_off, u_long dhead_off, u_long shead_off,
    u_long sphead_off, bool *first)
{
        char    *buf;
        int     ret, type;
        struct  xsocket *so;
        struct  xunpgen *xug, *oxug;
        struct  xunpcb *xunp;
        u_long  head_off;

        buf = NULL;
        for (type = SOCK_STREAM; type <= SOCK_SEQPACKET; type++) {
                if (live)
                        ret = pcblist_sysctl(type, &buf);
                else {
                        head_off = 0;
                        switch (type) {
                        case SOCK_STREAM:
                                head_off = shead_off;
                                break;

                        case SOCK_DGRAM:
                                head_off = dhead_off;
                                break;

                        case SOCK_SEQPACKET:
                                head_off = sphead_off;
                                break;
                        }
                        ret = pcblist_kvm(count_off, gencnt_off, head_off,
                            &buf);
                }
                if (ret == -1)
                        continue;
                if (ret < 0)
                        return;

                oxug = xug = (struct xunpgen *)buf;
                for (xug = (struct xunpgen *)((char *)xug + xug->xug_len);
                    xug->xug_len > sizeof(struct xunpgen);
                    xug = (struct xunpgen *)((char *)xug + xug->xug_len)) {
                        xunp = (struct xunpcb *)xug;
                        so = &xunp->xu_socket;

                        /* Ignore PCBs which were freed during copyout. */
                        if (xunp->unp_gencnt > oxug->xug_gen)
                                continue;
                        if (*first) {
                                xo_open_list("socket");
                                *first = false;
                        }
                        xo_open_instance("socket");
                        unixdomainpr(xunp, so);
                        xo_close_instance("socket");
                }
                if (xug != oxug && xug->xug_gen != oxug->xug_gen) {
                        if (oxug->xug_count > xug->xug_count) {
                                xo_emit("Some {:type/%s} sockets may have "
                                    "been {:action/deleted}.\n",
                                    socktype[type]);
                        } else if (oxug->xug_count < xug->xug_count) {
                                xo_emit("Some {:type/%s} sockets may have "
                                    "been {:action/created}.\n",
                                    socktype[type]);
                        } else {
                                xo_emit("Some {:type/%s} sockets may have "
                                    "been {:action/created or deleted}",
                                    socktype[type]);
                        }
                }
                free(buf);
        }
}

static void
unixdomainpr(struct xunpcb *xunp, struct xsocket *so)
{
        struct sockaddr_un *sa;
        static int first = 1;
        char buf1[33];
        static const char *titles[2] = {
            "{T:/%-8.8s} {T:/%-6.6s} {T:/%-6.6s} {T:/%-6.6s} {T:/%8.8s} "
            "{T:/%8.8s} {T:/%8.8s} {T:/%8.8s} {T:Addr}\n",
            "{T:/%-16.16s} {T:/%-6.6s} {T:/%-6.6s} {T:/%-6.6s} {T:/%16.16s} "
            "{T:/%16.16s} {T:/%16.16s} {T:/%16.16s} {T:Addr}\n"
        };
        static const char *format[2] = {
            "{q:address/%8lx} {t:type/%-6.6s} "
            "{:receive-bytes-waiting/%6u} "
            "{:send-bytes-waiting/%6u} "
            "{q:vnode/%8lx} {q:connection/%8lx} "
            "{q:first-reference/%8lx} {q:next-reference/%8lx}",
            "{q:address/%16lx} {t:type/%-6.6s} "
            "{:receive-bytes-waiting/%6u} "
            "{:send-bytes-waiting/%6u} "
            "{q:vnode/%16lx} {q:connection/%16lx} "
            "{q:first-reference/%16lx} {q:next-reference/%16lx}"
        };
        int fmt = (sizeof(void *) == 8) ? 1 : 0;

        sa = (xunp->xu_addr.sun_family == AF_UNIX) ? &xunp->xu_addr : NULL;

        if (first && !Lflag) {
                xo_emit("{T:Active UNIX domain sockets}\n");
                xo_emit(titles[fmt],
                    "Address", "Type", "Recv-Q", "Send-Q",
                    "Inode", "Conn", "Refs", "Nextref");
                first = 0;
        }

        if (Lflag && so->so_qlimit == 0)
                return;

        if (Lflag) {
                snprintf(buf1, sizeof buf1, "%u/%u/%u", so->so_qlen,
                    so->so_incqlen, so->so_qlimit);
                xo_emit("unix  {d:socket/%-32.32s}{e:queue-length/%u}"
                    "{e:incomplete-queue-length/%u}{e:queue-limit/%u}",
                    buf1, so->so_qlen, so->so_incqlen, so->so_qlimit);
        } else {
                xo_emit(format[fmt],
                    (long)so->so_pcb, socktype[so->so_type], so->so_rcv.sb_cc,
                    so->so_snd.sb_cc, (long)xunp->unp_vnode,
                    (long)xunp->unp_conn, (long)xunp->xu_firstref,
                    (long)xunp->xu_nextref);
        }
        if (sa)
                xo_emit(" {:path/%.*s}",
                    (int)(sa->sun_len - offsetof(struct sockaddr_un, sun_path)),
                    sa->sun_path);
        xo_emit("\n");
}