/*      $NetBSD: ruserpass.c,v 1.35 2024/10/04 18:04:06 christos Exp $  */

/*
 * Copyright (c) 1985, 1993, 1994
 *      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>
#ifndef lint
#if 0
static char sccsid[] = "@(#)ruserpass.c 8.4 (Berkeley) 4/27/95";
#else
__RCSID("$NetBSD: ruserpass.c,v 1.35 2024/10/04 18:04:06 christos Exp $");
#endif
#endif /* not lint */

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

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "ftp_var.h"

static  int token(void);
static  FILE *cfile;

#define DEFAULT 1
#define LOGIN   2
#define PASSWD  3
#define ACCOUNT 4
#define MACDEF  5
#define ID      10
#define MACH    11

static char tokval[100];

static struct toktab {
        const char *tokstr;
        int tval;
} toktab[] = {
        { "default",    DEFAULT },
        { "login",      LOGIN },
        { "password",   PASSWD },
        { "passwd",     PASSWD },
        { "account",    ACCOUNT },
        { "machine",    MACH },
        { "macdef",     MACDEF },
        { NULL,         0 }
};

static int
match_host_domain(const char *host, const char *domain, const char *tokv)
{
        const char *tmp;

        if (strcasecmp(host, tokval) == 0)
                return 1;

        return (tmp = strchr(host, '.')) != NULL &&
            strcasecmp(tmp, domain) == 0 &&
            strncasecmp(host, tokv, tmp - host) == 0 &&
            tokv[tmp - host] == '\0';
}

int
ruserpass(const char *host, char **aname, char **apass, char **aacct)
{
        char *tmp;
        const char *mydomain;
        char myname[MAXHOSTNAMELEN + 1];
        int t, i, c, usedefault = 0;
        struct stat stb;

        if (netrc[0] == '\0')
                return (0);
        cfile = fopen(netrc, "r");
        if (cfile == NULL) {
                if (errno != ENOENT)
                        warn("Can't read `%s'", netrc);
                return (0);
        }
        if (gethostname(myname, sizeof(myname)) < 0)
                myname[0] = '\0';
        myname[sizeof(myname) - 1] = '\0';
        if ((mydomain = strchr(myname, '.')) == NULL)
                mydomain = "";
 next:
        while ((t = token()) > 0) switch(t) {

        case DEFAULT:
                usedefault = 1;
                /* FALL THROUGH */

        case MACH:
                if (!usedefault) {
                        if ((t = token()) == -1)
                                goto bad;
                        if (t != ID)
                                continue;
                        /*
                         * Allow match either for user's input host name
                         * or official hostname.  Also allow match of
                         * incompletely-specified host in local domain.
                         */
                        if (match_host_domain(hostname, mydomain, tokval))
                                goto match;
                        if (match_host_domain(host, mydomain, tokval))
                                goto match;
                        continue;
                }
        match:
                while ((t = token()) > 0 &&
                    t != MACH && t != DEFAULT) switch(t) {

                case LOGIN:
                        if ((t = token()) == -1)
                                goto bad;
                        if (t) {
                                if (*aname == NULL)
                                        *aname = ftp_strdup(tokval);
                                else {
                                        if (strcmp(*aname, tokval))
                                                goto next;
                                }
                        }
                        break;
                case PASSWD:
                        if ((*aname == NULL || strcmp(*aname, "anonymous")) &&
                            fstat(fileno(cfile), &stb) >= 0 &&
                            (stb.st_mode & 077) != 0) {
        warnx("Error: .netrc file is readable by others");
        warnx("Remove password or make file unreadable by others");
                                goto bad;
                        }
                        if ((t = token()) == -1)
                                goto bad;
                        if (t && *apass == NULL)
                                *apass = ftp_strdup(tokval);
                        break;
                case ACCOUNT:
                        if (fstat(fileno(cfile), &stb) >= 0
                            && (stb.st_mode & 077) != 0) {
        warnx("Error: .netrc file is readable by others");
        warnx("Remove account or make file unreadable by others");
                                goto bad;
                        }
                        if ((t = token()) == -1)
                                goto bad;
                        if (t && *aacct == NULL)
                                *aacct = ftp_strdup(tokval);
                        break;
                case MACDEF:
                        if (proxy) {
                                (void)fclose(cfile);
                                return (0);
                        }
                        while ((c = getc(cfile)) != EOF)
                                if (c != ' ' && c != '\t')
                                        break;
                        if (c == EOF || c == '\n') {
                                fputs("Missing macdef name argument.\n",
                                    ttyout);
                                goto bad;
                        }
                        if (macnum == 16) {
                                fputs(
                            "Limit of 16 macros have already been defined.\n",
                                    ttyout);
                                goto bad;
                        }
                        tmp = macros[macnum].mac_name;
                        *tmp++ = c;
                        for (i = 0; i < 8 && (c = getc(cfile)) != EOF &&
                            !isspace(c); ++i) {
                                *tmp++ = c;
                        }
                        if (c == EOF) {
                                fputs(
                            "Macro definition missing null line terminator.\n",
                                    ttyout);
                                goto bad;
                        }
                        *tmp = '\0';
                        if (c != '\n') {
                                while ((c = getc(cfile)) != EOF && c != '\n');
                        }
                        if (c == EOF) {
                                fputs(
                            "Macro definition missing null line terminator.\n",
                                    ttyout);
                                goto bad;
                        }
                        if (macnum == 0) {
                                macros[macnum].mac_start = macbuf;
                        }
                        else {
                                macros[macnum].mac_start =
                                    macros[macnum-1].mac_end + 1;
                        }
                        tmp = macros[macnum].mac_start;
                        while (tmp != macbuf + 4096) {
                                if ((c = getc(cfile)) == EOF) {
                                        fputs(
                            "Macro definition missing null line terminator.\n",
                                            ttyout);
                                        goto bad;
                                }
                                *tmp = c;
                                if (*tmp == '\n') {
                                        if (tmp == macros[macnum].mac_start) {
                                                macros[macnum++].mac_end = tmp;
                                                break;
                                        } else if (*(tmp - 1) == '\0') {
                                                macros[macnum++].mac_end =
                                                    tmp - 1;
                                                break;
                                        }
                                        *tmp = '\0';
                                }
                                tmp++;
                        }
                        if (tmp == macbuf + 4096) {
                                fputs("4 KiB macro buffer exceeded.\n",
                                    ttyout);
                                goto bad;
                        }
                        break;
                default:
                        warnx("Unknown .netrc keyword `%s'", tokval);
                        break;
                }
                goto done;
        }
 done:
        if (t == -1)
                goto bad;
        (void)fclose(cfile);
        return (0);
 bad:
        (void)fclose(cfile);
        return (-1);
}

static int
token(void)
{
        char *cp;
        int c;
        struct toktab *t;

        if (feof(cfile) || ferror(cfile))
                return (0);
        while ((c = getc(cfile)) != EOF &&
            (c == '\n' || c == '\t' || c == ' ' || c == ','))
                continue;
        if (c == EOF)
                return (0);
        cp = tokval;
        if (c == '"') {
                while ((c = getc(cfile)) != EOF && c != '"') {
                        if (c == '\\')
                                if ((c = getc(cfile)) == EOF)
                                        break;
                        *cp++ = c;
                        if (cp == tokval + sizeof(tokval)) {
                                warnx("Token in .netrc too long");
                                return (-1);
                        }
                }
        } else {
                *cp++ = c;
                while ((c = getc(cfile)) != EOF
                    && c != '\n' && c != '\t' && c != ' ' && c != ',') {
                        if (c == '\\')
                                if ((c = getc(cfile)) == EOF)
                                        break;
                        *cp++ = c;
                        if (cp == tokval + sizeof(tokval)) {
                                warnx("Token in .netrc too long");
                                return (-1);
                        }
                }
        }
        *cp = 0;
        if (tokval[0] == 0)
                return (0);
        for (t = toktab; t->tokstr; t++)
                if (!strcmp(t->tokstr, tokval))
                        return (t->tval);
        return (ID);
}