/*      $NetBSD: util.c,v 1.31 2022/05/24 20:50:20 andvar Exp $ */

/*
 * Copyright (c) 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Tony Nardo of the Johns Hopkins University/Applied Physics Lab.
 *
 * 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.
 */

/*
 * Portions Copyright (c) 1983, 1995, 1996 Eric P. Allman
 *
 * This code is derived from software contributed to Berkeley by
 * Tony Nardo of the Johns Hopkins University/Applied Physics Lab.
 *
 * 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.
 */

#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)util.c      8.3 (Berkeley) 4/28/95";
#else
__RCSID("$NetBSD: util.c,v 1.31 2022/05/24 20:50:20 andvar Exp $");
#endif
#endif /* not lint */

#include <sys/param.h>
#include <sys/stat.h>

#include <db.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "utmpentry.h"

#include "finger.h"
#include "extern.h"

static void      find_idle_and_ttywrite(WHERE *);
static void      userinfo(PERSON *, struct passwd *);
static WHERE    *walloc(PERSON *);

int
match(struct passwd *pw, char *user)
{
        char *p;
        char *bp, name[1024];

        if (!strcasecmp(pw->pw_name, user))
                return(1);

        (void)strlcpy(bp = tbuf, pw->pw_gecos, sizeof(tbuf));

        /* Ampersands get replaced by the login name. */
        if (!(p = strsep(&bp, ",")))
                return(0);

        expandusername(p, pw->pw_name, name, sizeof(name));
        bp = name;
        while ((p = strsep(&bp, "\t ")))
                if (!strcasecmp(p, user))
                        return(1);
        return(0);
}

/* inspired by usr.sbin/sendmail/util.c::buildfname */
void
expandusername(const char *gecos, const char *login, char *buf, int buflen)
{
        const char *p;
        char *bp;

        /* why do we skip asterisks!?!? */
        if (*gecos == '*')
                gecos++;
        bp = buf;

        /* copy gecos, interpolating & to be full name */
        for (p = gecos; *p != '\0'; p++) {
                if (bp >= &buf[buflen - 1]) {
                        /* buffer overflow - just use login name */
                        snprintf(buf, buflen, "%s", login);
                        buf[buflen - 1] = '\0';
                        return;
                }
                if (*p == '&') {
                        /* interpolate full name */
                        snprintf(bp, buflen - (bp - buf), "%s", login);
                        *bp = toupper((unsigned char)*bp);
                        bp += strlen(bp);
                }
                else
                        *bp++ = *p;
        }
        *bp = '\0';
}

void
enter_lastlog(PERSON *pn)
{
        WHERE *w;
        static int opened;
#ifdef SUPPORT_UTMPX
# define ll_time        ll_tv.tv_sec
# define UT_LINESIZE    _UTX_LINESIZE
# define UT_HOSTSIZE    _UTX_HOSTSIZE
        static DB *lldb = NULL;
        DBT key, data;
        struct lastlogx ll;
#else
        static int fd;
        struct lastlog ll;
#endif
        char doit = 0;

        (void)memset(&ll, 0, sizeof(ll));

        /* some systems may not maintain lastlog, don't report errors. */
        if (!opened) {
#ifdef SUPPORT_UTMPX
                lldb = dbopen(_PATH_LASTLOGX, O_RDONLY|O_SHLOCK, 0, DB_HASH, NULL);
#else
                fd = open(_PATH_LASTLOG, O_RDONLY, 0);
#endif
                opened = 1;
        }
#ifdef SUPPORT_UTMPX
        if (lldb != NULL) {
                key.data = &pn->uid;
                key.size = sizeof(pn->uid);
                if ((*lldb->get)(lldb, &key, &data, 0) == 0 &&
                    data.size == sizeof(ll))
                        (void)memcpy(&ll, data.data, sizeof(ll));
        }
#else
        if (fd == -1 ||
            lseek(fd, (off_t)pn->uid * sizeof(ll), SEEK_SET) !=
            (off_t)pn->uid * (off_t)sizeof(ll) ||
            read(fd, (char *)&ll, sizeof(ll)) != sizeof(ll)) {
                        /* as if never logged in */
                        ll.ll_line[0] = ll.ll_host[0] = '\0';
                        ll.ll_time = 0;
                }
#endif
        if ((w = pn->whead) == NULL)
                doit = 1;
        else if (ll.ll_time != 0) {
                /* if last login is earlier than some current login */
                for (; !doit && w != NULL; w = w->next)
                        if (w->info == LOGGEDIN && w->loginat < ll.ll_time)
                                doit = 1;
                /*
                 * and if it's not any of the current logins
                 * can't use time comparison because there may be a small
                 * discrepancy since login calls time() twice
                 */
                for (w = pn->whead; doit && w != NULL; w = w->next)
                        if (w->info == LOGGEDIN &&
                            strncmp(w->tty, ll.ll_line, UT_LINESIZE) == 0)
                                doit = 0;
        }
        if (doit) {
                w = walloc(pn);
                w->info = LASTLOG;
                if ((w->tty = malloc(UT_LINESIZE + 1)) == NULL)
                        err(1, NULL);
                memcpy(w->tty, ll.ll_line, UT_LINESIZE);
                w->tty[UT_LINESIZE] = '\0';
                if ((w->host = malloc(UT_HOSTSIZE + 1)) == NULL)
                        err(1, NULL);
                memcpy(w->host, ll.ll_host, UT_HOSTSIZE);
                w->host[UT_HOSTSIZE] = '\0';
                w->loginat = ll.ll_time;
        }
}

void
enter_where(struct utmpentry *ep, PERSON *pn)
{
        WHERE *w = walloc(pn);

        w->info = LOGGEDIN;
        w->tty = ep->line;
        w->host = ep->host;
        w->loginat = (time_t)ep->tv.tv_sec;
        find_idle_and_ttywrite(w);
}

PERSON *
enter_person(struct passwd *pw)
{
        DBT data, key;
        PERSON *pn;

        if (db == NULL &&
            (db = dbopen(NULL, O_RDWR, 0, DB_BTREE, NULL)) == NULL)
                err(1, NULL);

        key.data = (char *)pw->pw_name;
        key.size = strlen(pw->pw_name);

        switch ((*db->get)(db, &key, &data, 0)) {
        case 0:
                memmove(&pn, data.data, sizeof pn);
                return (pn);
        default:
        case -1:
                err(1, "db get");
                /* NOTREACHED */
        case 1:
                ++entries;
                pn = palloc();
                userinfo(pn, pw);
                pn->whead = NULL;

                data.size = sizeof(PERSON *);
                data.data = &pn;
                if ((*db->put)(db, &key, &data, 0))
                        err(1, "db put");
                return (pn);
        }
}

PERSON *
find_person(char *name)
{
        DBT data, key;
        PERSON *p;

        if (!db)
                return(NULL);

        key.data = name;
        key.size = strlen(name);

        if ((*db->get)(db, &key, &data, 0))
                return (NULL);
        memmove(&p, data.data, sizeof p);
        return (p);
}

PERSON *
palloc(void)
{
        PERSON *p;

        if ((p = malloc((u_int) sizeof(PERSON))) == NULL)
                err(1, NULL);
        return(p);
}

static WHERE *
walloc(PERSON *pn)
{
        WHERE *w;

        if ((w = malloc((u_int) sizeof(WHERE))) == NULL)
                err(1, NULL);
        if (pn->whead == NULL)
                pn->whead = pn->wtail = w;
        else {
                pn->wtail->next = w;
                pn->wtail = w;
        }
        w->next = NULL;
        return(w);
}

char *
prphone(char *num)
{
        char *p;
        int len;
        static char pbuf[15];

        /* don't touch anything if the user has their own formatting */
        for (p = num; *p; ++p)
                if (!isdigit((unsigned char)*p))
                        return(num);
        len = p - num;
        p = pbuf;
        switch(len) {
        case 11:                        /* +0-123-456-7890 */
                *p++ = '+';
                *p++ = *num++;
                *p++ = '-';
                /* FALLTHROUGH */
        case 10:                        /* 012-345-6789 */
                *p++ = *num++;
                *p++ = *num++;
                *p++ = *num++;
                *p++ = '-';
                /* FALLTHROUGH */
        case 7:                         /* 012-3456 */
                *p++ = *num++;
                *p++ = *num++;
                *p++ = *num++;
                break;
        case 5:                         /* x0-1234 */
        case 4:                         /* x1234 */
                *p++ = 'x';
                *p++ = *num++;
                break;
        default:
                return(num);
        }
        if (len != 4) {
                *p++ = '-';
                *p++ = *num++;
        }
        *p++ = *num++;
        *p++ = *num++;
        *p++ = *num++;
        *p = '\0';
        return(pbuf);
}

static void
find_idle_and_ttywrite(WHERE *w)
{
        struct stat sb;

        (void)snprintf(tbuf, sizeof(tbuf), "%s/%s", _PATH_DEV, w->tty);
        if (stat(tbuf, &sb) < 0) {
                warn("%s", tbuf);
                w->idletime = 0;
                w->writable = 0;
                return;
        }
        w->idletime = now < sb.st_atime ? 0 : now - sb.st_atime;

#define TALKABLE        0220            /* tty is writable if 220 mode */
        w->writable = ((sb.st_mode & TALKABLE) == TALKABLE);
}

static void
userinfo(PERSON *pn, struct passwd *pw)
{
        char *p;
        char *bp, name[1024];
        struct stat sb;

        pn->realname = pn->office = pn->officephone = pn->homephone = NULL;

        pn->uid = pw->pw_uid;
        pn->name = strdup(pw->pw_name);
        pn->dir = strdup(pw->pw_dir);
        pn->shell = strdup(pw->pw_shell);

        (void)strlcpy(bp = tbuf, pw->pw_gecos, sizeof(tbuf));

        /* ampersands get replaced by the login name */
        if (!(p = strsep(&bp, ",")))
                return;
        expandusername(p, pw->pw_name, name, sizeof(name));
        pn->realname = strdup(name);
        pn->office = ((p = strsep(&bp, ",")) && *p) ?
            strdup(p) : NULL;
        pn->officephone = ((p = strsep(&bp, ",")) && *p) ?
            strdup(p) : NULL;
        pn->homephone = ((p = strsep(&bp, ",")) && *p) ?
            strdup(p) : NULL;
        (void)snprintf(tbuf, sizeof(tbuf), "%s/%s", _PATH_MAILDIR,
            pw->pw_name);
        pn->mailrecv = -1;              /* -1 == not_valid */
        if (stat(tbuf, &sb) < 0) {
                if (errno != ENOENT) {
                        (void)fprintf(stderr,
                            "finger: %s: %s\n", tbuf, strerror(errno));
                        return;
                }
        } else if (sb.st_size != 0) {
                pn->mailrecv = sb.st_mtime;
                pn->mailread = sb.st_atime;
        }
}