/*      $OpenBSD: getprotoent.c,v 1.14 2026/03/10 00:06:39 deraadt Exp $ */
/*
 * Copyright (c) 1983, 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/socket.h>

#include <errno.h>
#include <limits.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>

void
setprotoent_r(int f, struct protoent_data *pd)
{
        if (pd->fp == NULL) {
                int fd = __pledge_open(_PATH_PROTOCOLS, O_RDONLY|O_CLOEXEC);
                if (fd != -1)
                        pd->fp = fdopen(fd, "r" );
                if (pd->fp == NULL)
                        close(fd);
        } else
                rewind(pd->fp);
        pd->stayopen |= f;
}
DEF_WEAK(setprotoent_r);

void
endprotoent_r(struct protoent_data *pd)
{
        if (pd->fp) {
                fclose(pd->fp);
                pd->fp = NULL;
        }
        free(pd->aliases);
        pd->aliases = NULL;
        pd->maxaliases = 0;
        free(pd->line);
        pd->line = NULL;
        pd->stayopen = 0;
}
DEF_WEAK(endprotoent_r);

int
getprotoent_r(struct protoent *pe, struct protoent_data *pd)
{
        char *p, *cp, **q, *endp;
        size_t len;
        long l;
        int serrno;

        if (pd->fp == NULL && (pd->fp = fopen(_PATH_PROTOCOLS, "re" )) == NULL)
                return (-1);
again:
        if ((p = fgetln(pd->fp, &len)) == NULL)
                return (-1);
        if (len == 0 || *p == '#' || *p == '\n')
                goto again;
        if (p[len-1] == '\n')
                len--;
        if ((cp = memchr(p, '#', len)) != NULL)
                len = cp - p;
        cp = realloc(pd->line, len + 1);
        if (cp == NULL)
                return (-1);
        pd->line = pe->p_name = memcpy(cp, p, len);
        cp[len] = '\0';
        cp = strpbrk(cp, " \t");
        if (cp == NULL)
                goto again;
        *cp++ = '\0';
        while (*cp == ' ' || *cp == '\t')
                cp++;
        p = strpbrk(cp, " \t");
        if (p != NULL)
                *p++ = '\0';
        l = strtol(cp, &endp, 10);
        if (endp == cp || *endp != '\0' || l < 0 || l >= INT_MAX)
                goto again;
        pe->p_proto = l;
        if (pd->aliases == NULL) {
                pd->maxaliases = 5;
                pd->aliases = calloc(pd->maxaliases, sizeof(char *));
                if (pd->aliases == NULL) {
                        serrno = errno;
                        endprotoent_r(pd);
                        errno = serrno;
                        return (-1);
                }
        }
        q = pe->p_aliases = pd->aliases;
        if (p != NULL) {
                cp = p;
                while (cp && *cp) {
                        if (*cp == ' ' || *cp == '\t') {
                                cp++;
                                continue;
                        }
                        if (q == &pe->p_aliases[pd->maxaliases - 1]) {
                                p = reallocarray(pe->p_aliases,
                                    pd->maxaliases, 2 * sizeof(char *));
                                if (p == NULL) {
                                        serrno = errno;
                                        endprotoent_r(pd);
                                        errno = serrno;
                                        return (-1);
                                }
                                pd->maxaliases *= 2;
                                q = (char **)p + (q - pe->p_aliases);
                                pe->p_aliases = pd->aliases = (char **)p;
                        }
                        *q++ = cp;
                        cp = strpbrk(cp, " \t");
                        if (cp != NULL)
                                *cp++ = '\0';
                }
        }
        *q = NULL;
        return (0);
}
DEF_WEAK(getprotoent_r);

struct protoent_data _protoent_data;    /* shared with getproto{,name}.c */

void
setprotoent(int f)
{
        setprotoent_r(f, &_protoent_data);
}

void
endprotoent(void)
{
        endprotoent_r(&_protoent_data);
}

struct protoent *
getprotoent(void)
{
        static struct protoent proto;

        if (getprotoent_r(&proto, &_protoent_data) != 0)
                return (NULL);
        return (&proto);
}