/*      $NetBSD: common.c,v 1.45 2026/03/10 21:59:30 andvar Exp $       */

/*
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * 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>
#ifndef lint
#if 0
static char sccsid[] = "@(#)common.c    8.5 (Berkeley) 4/28/95";
#else
__RCSID("$NetBSD: common.c,v 1.45 2026/03/10 21:59:30 andvar Exp $");
#endif
#endif /* not lint */

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

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>

#include <dirent.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ifaddrs.h>
#include "lp.h"
#include "lp.local.h"
#include "pathnames.h"

/*
 * Routines and data common to all the line printer functions.
 */

const char      *AF;            /* accounting file */
long             BR;            /* baud rate if lp is a tty */
const char      *CF;            /* name of cifplot filter (per job) */
const char      *DF;            /* name of tex filter (per job) */
long             DU;            /* daemon user-id */
long             FC;            /* flags to clear if lp is a tty */
const char      *FF;            /* form feed string */
long             FS;            /* flags to set if lp is a tty */
const char      *GF;            /* name of graph(1G) filter (per job) */
long             HL;            /* print header last */
const char      *IF;            /* name of input filter (created per job) */
const char      *LF;            /* log file for error messages */
const char      *LO;            /* lock file name */
const char      *LP;            /* line printer device name */
long             MC;            /* maximum number of copies allowed */
const char      *MS;            /* stty flags to set if lp is a tty */
long             MX;            /* maximum number of blocks to copy */
const char      *NF;            /* name of ditroff filter (per job) */
const char      *OF;            /* name of output filter (created once) */
const char      *PF;            /* name of postscript filter (per job) */
long             PL;            /* page length */
long             PW;            /* page width */
long             PX;            /* page width in pixels */
long             PY;            /* page length in pixels */
const char      *RF;            /* name of fortran text filter (per job) */
const char      *RG;            /* restricted group */
const char      *RM;            /* remote machine name */
const char      *RP;            /* remote printer name */
long             RS;            /* restricted to those with local accounts */
long             RW;            /* open LP for reading and writing */
long             SB;            /* short banner instead of normal header */
long             SC;            /* suppress multiple copies */
const char      *SD;            /* spool directory */
long             SF;            /* suppress FF on each print job */
long             SH;            /* suppress header page */
const char      *ST;            /* status file name */
const char      *TF;            /* name of troff filter (per job) */
const char      *TR;            /* trailer string to be output when Q empties */
const char      *VF;            /* name of vplot/vrast filter (per job) */
long             XC;            /* flags to clear for local mode */
long             XS;            /* flags to set for local mode */

char    line[BUFSIZ];
int     remote;         /* true if sending files to a remote host */

extern uid_t    uid, euid;

static int compar(const void *, const void *);

const char *
gethost(const char *hname)
{
        const char *p = strchr(hname, '@');
        return p ? ++p : hname;
}

/*
 * Create a TCP connection to host "rhost". If "rhost" is of the
 * form port@host, use the specified port. Otherwise use the
 * default printer port. Most of this code comes from rcmd.c.
 */
int
getport(const char *rhost)
{
        struct addrinfo hints, *res, *r;
        u_int timo = 1;
        int s, lport = IPPORT_RESERVED - 1;
        int error;
        int refuse, trial;
        char hbuf[NI_MAXSERV], *ptr;
        const char *port = "printer";
        const char *hostname = rhost;

        /*
         * Get the host address and port number to connect to.
         */
        if (rhost == NULL)
                fatal("no remote host to connect to");
        (void)strlcpy(hbuf, rhost, sizeof(hbuf));
        for (ptr = hbuf; *ptr; ptr++) 
                if (*ptr == '@') {
                        *ptr++ = '\0';
                        port = hbuf;
                        hostname = ptr;
                        break;
                }
        (void)memset(&hints, 0, sizeof(hints));
        hints.ai_family = PF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;
        error = getaddrinfo(hostname, port, &hints, &res);
        if (error)
                fatal("printer/tcp: %s", gai_strerror(error));

        /*
         * Try connecting to the server.
         */
retry:
        s = -1;
        refuse = trial = 0;
        for (r = res; r; r = r->ai_next) {
                trial++;
retryport:
                seteuid(euid);
                s = rresvport_af(&lport, r->ai_family);
                seteuid(uid);
                if (s < 0)
                        return(-1);
                if (connect(s, r->ai_addr, r->ai_addrlen) < 0) {
                        error = errno;
                        (void)close(s);
                        s = -1;
                        errno = error;
                        if (errno == EADDRINUSE) {
                                lport--;
                                goto retryport;
                        } else if (errno == ECONNREFUSED)
                                refuse++;
                        continue;
                } else
                        break;
        }
        if (s < 0 && trial == refuse && timo <= 16) {
                sleep(timo);
                timo *= 2;
                goto retry;
        }
        if (res)
                freeaddrinfo(res);
        return(s);
}

/*
 * Getline reads a line from the control file cfp, removes tabs, converts
 *  new-line to null and leaves it in line.
 * Returns 0 at EOF or the number of characters read.
 */
size_t
get_line(FILE *cfp)
{
        size_t linel = 0;
        int c;
        char *lp = line;

        while ((c = getc(cfp)) != '\n' && linel+1<sizeof(line)) {
                if (c == EOF)
                        return(0);
                if (c == '\t') {
                        do {
                                *lp++ = ' ';
                                linel++;
                        } while ((linel & 07) != 0 && linel+1 < sizeof(line));
                        continue;
                }
                *lp++ = c;
                linel++;
        }
        *lp++ = '\0';
        return(linel);
}

/*
 * Scan the current directory and make a list of daemon files sorted by
 * creation time.
 * Return the number of entries and a pointer to the list.
 */
int
getq(struct queue **namelist[])
{
        struct dirent *d;
        struct queue *q, **queue = NULL, **nqueue;
        struct stat stbuf;
        DIR *dirp;
        u_int nitems = 0, arraysz;

        seteuid(euid);
        dirp = opendir(SD);
        seteuid(uid);
        if (dirp == NULL)
                return(-1);
        if (fstat(dirp->dd_fd, &stbuf) < 0)
                goto errdone;

        /*
         * Estimate the array size by taking the size of the directory file
         * and dividing it by a multiple of the minimum size entry. 
         */
        arraysz = (int)(stbuf.st_size / 24);
        queue = calloc(arraysz, sizeof(struct queue *));
        if (queue == NULL)
                goto errdone;

        while ((d = readdir(dirp)) != NULL) {
                if (d->d_name[0] != 'c' || d->d_name[1] != 'f'
                    || d->d_name[2] == '\0')
                        continue;       /* daemon control files only */
                seteuid(euid);
                if (stat(d->d_name, &stbuf) < 0) {
                        seteuid(uid);
                        continue;       /* Doesn't exist */
                }
                seteuid(uid);
                q = (struct queue *)malloc(sizeof(time_t)+strlen(d->d_name)+1);
                if (q == NULL)
                        goto errdone;
                q->q_time = stbuf.st_mtime;
                strcpy(q->q_name, d->d_name);   /* XXX: strcpy is safe */
                /*
                 * Check to make sure the array has space left and
                 * realloc the maximum size.
                 */
                if (++nitems > arraysz) {
                        nqueue = (struct queue **)realloc(queue,
                                arraysz * 2 * sizeof(struct queue *));
                        if (nqueue == NULL) {
                                free(q);
                                goto errdone;
                        }
                        (void)memset(&nqueue[arraysz], 0,
                            arraysz * sizeof(nqueue[0]));
                        queue = nqueue;
                        arraysz *= 2;
                }
                queue[nitems-1] = q;
        }
        closedir(dirp);
        if (nitems)
                qsort(queue, nitems, sizeof(struct queue *), compar);
        *namelist = queue;
        return(nitems);

errdone:
        freeq(queue, nitems);
        closedir(dirp);
        return(-1);
}

void
freeq(struct queue **namelist, u_int nitems)
{
        u_int i;
        if (namelist == NULL)
                return;
        for (i = 0; i < nitems; i++)
                if (namelist[i])
                        free(namelist[i]);
        free(namelist);
}

/*
 * Compare modification times.
 */
static int
compar(const void *p1, const void *p2)
{
        const struct queue *const *q1 = p1;
        const struct queue *const *q2 = p2;
        int j1, j2;

        if ((*q1)->q_time < (*q2)->q_time)
                return -1;
        if ((*q1)->q_time > (*q2)->q_time)
                return 1;

        j1 = atoi((*q1)->q_name+3);
        j2 = atoi((*q2)->q_name+3);

        if (j1 == j2)
                return 0;
        if ((j1 < j2 && j2-j1 < 500) || (j1 > j2 && j1-j2 > 500))
                return -1;
        if ((j1 < j2 && j2-j1 > 500) || (j1 > j2 && j1-j2 < 500))
                return 1;
 
        return 0;
}

/*
 * Figure out whether the local machine is the same
 * as the remote machine (RM) entry (if it exists).
 */
const char *
checkremote(void)
{
        struct addrinfo hints, *res0;
        static char errbuf[128];
        int error;
        struct ifaddrs *ifap;
#if defined(INET6) && defined(__KAME__)
        char lname[NI_MAXHOST], rname[NI_MAXHOST];
        struct addrinfo *res;
        struct ifaddrs *ifa;
        const int niflags = NI_NUMERICHOST;
        struct sockaddr_in6 sin6;
        struct sockaddr_in6 *sin6p;
#endif

        remote = 0;     /* assume printer is local on failure */

        if (RM == NULL)
                return NULL;

        /* get the local interface addresses */
        if (getifaddrs(&ifap) < 0) {
                (void)snprintf(errbuf, sizeof(errbuf),
                    "unable to get local interface address: %s",
                    strerror(errno));
                return errbuf;
        }

        /* get the remote host addresses (RM) */
        memset(&hints, 0, sizeof(hints));
        hints.ai_flags = AI_CANONNAME;
        hints.ai_family = PF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;
        error = getaddrinfo(gethost(RM), NULL, &hints, &res0);
        if (error) {
                (void)snprintf(errbuf, sizeof(errbuf),
                    "unable to resolve remote machine %s: %s",
                    RM, gai_strerror(error));
                freeifaddrs(ifap);
                return errbuf;
        }

        remote = 1;     /* assume printer is remote */

#if defined(INET6) && defined(__KAME__)
        for (res = res0; res; res = res->ai_next) {
                if (getnameinfo(res->ai_addr, res->ai_addrlen,
                    rname, sizeof(rname), NULL, 0, niflags) != 0)
                        continue;
                for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
                        sin6p = (struct sockaddr_in6 *)ifa->ifa_addr;
                        if (ifa->ifa_addr->sa_family == AF_INET6 &&
                            ifa->ifa_addr->sa_len == sizeof(sin6)) {
                                inet6_getscopeid(sin6p, 3);
                                if (getnameinfo((struct sockaddr *)&sin6,
                                    sin6.sin6_len, lname, sizeof(lname),
                                    NULL, 0, niflags) != 0)
                                        continue;
                                if (strcmp(rname, lname) == 0) {
                                        remote = 0;
                                        goto done;
                                }
                        }
                }
        }
done:
#endif
        freeaddrinfo(res0);
        freeifaddrs(ifap);
        return NULL;
}

/* sleep n milliseconds */
void
delay(int n)
{
        struct timespec tdelay;

        if (n <= 0 || n > 10000)
                fatal("unreasonable delay period (%d)", n);
        tdelay.tv_sec = n / 1000;
        tdelay.tv_nsec = (n % 1000) * 1000000;
        nanosleep(&tdelay, NULL);
}

void
getprintcap(const char *pr)
{
        char *cp;
        const char *dp;
        int i;

        if ((i = cgetent(&bp, printcapdb, pr)) == -2)
                fatal("can't open printer description file");
        else if (i == -1)
                fatal("unknown printer: %s", pr);
        else if (i == -3)
                fatal("potential reference loop detected in printcap file");

        LP = cgetstr(bp, DEFLP, &cp) == -1 ? _PATH_DEFDEVLP : cp;
        RP = cgetstr(bp, "rp", &cp) == -1 ? DEFLP : cp;
        SD = cgetstr(bp, "sd", &cp) == -1 ? _PATH_DEFSPOOL : cp;
        LO = cgetstr(bp, "lo", &cp) == -1 ? DEFLOCK : cp;
        ST = cgetstr(bp, "st", &cp) == -1 ? DEFSTAT : cp;
        RM = cgetstr(bp, "rm", &cp) == -1 ? NULL : cp;
        if ((dp = checkremote()) != NULL)
                printf("Warning: %s\n", dp);
        LF = cgetstr(bp, "lf", &cp) == -1 ? _PATH_CONSOLE : cp;
}

/*
 * Make sure there's some work to do before forking off a child
 */
int
ckqueue(char *cap)
{
        struct dirent *d;
        DIR *dirp;
        const char *spooldir;
        char *sd = NULL;
        int rv = 0;

        spooldir = cgetstr(cap, "sd", &sd) == -1 ? _PATH_DEFSPOOL : sd;
        if ((dirp = opendir(spooldir)) == NULL) {
                rv = -1;
                goto out;
        }
        while ((d = readdir(dirp)) != NULL) {
                if (d->d_name[0] != 'c' || d->d_name[1] != 'f')
                        continue;       /* daemon control files only */
                rv = 1;
                break;
        }
out:
        if (dirp != NULL)
                closedir(dirp);
        if (spooldir != sd)
                free(sd);
        return (rv);
}