/*      $NetBSD: lcl_ho.c,v 1.1.1.2 2012/09/09 16:07:59 christos Exp $  */

/*
* Copyright (c) 1985, 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. 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.
*/

/*
* Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
* Portions Copyright (c) 1996-1999 by Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

/* from gethostnamadr.c 8.1 (Berkeley) 6/4/93 */
/* BIND Id: gethnamaddr.c,v 8.15 1996/05/22 04:56:30 vixie Exp $ */

#if defined(LIBC_SCCS) && !defined(lint)
static const char rcsid[] = "Id: lcl_ho.c,v 1.5 2006/03/09 23:57:56 marka Exp ";
#endif /* LIBC_SCCS and not lint */

/* Imports. */

#include "port_before.h"

#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>

#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>

#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <resolv.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <irs.h>
#include <isc/memcluster.h>

#include "port_after.h"

#include "irs_p.h"
#include "dns_p.h"
#include "lcl_p.h"

#ifdef SPRINTF_CHAR
# define SPRINTF(x) strlen(sprintf/**/x)
#else
# define SPRINTF(x) sprintf x
#endif

/* Definitions. */

#define MAXALIASES      35
#define MAXADDRS        35
#define Max(a,b)        ((a) > (b) ? (a) : (b))

#if PACKETSZ > 1024
#define MAXPACKET       PACKETSZ
#else
#define MAXPACKET       1024
#endif

struct pvt {
       FILE *          fp;
       struct hostent  host;
       char *          h_addr_ptrs[MAXADDRS + 1];
       char *          host_aliases[MAXALIASES];
       char            hostbuf[8*1024];
       u_char          host_addr[16];  /*%< IPv4 or IPv6 */
       struct __res_state  *res;
       void            (*free_res)(void *);
};

typedef union {
       int32_t al;
       char ac;
} align;

static const u_char mapped[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff };
static const u_char tunnelled[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 };

/* Forward. */

static void             ho_close(struct irs_ho *this);
static struct hostent * ho_byname(struct irs_ho *this, const char *name);
static struct hostent * ho_byname2(struct irs_ho *this, const char *name,
                                  int af);
static struct hostent * ho_byaddr(struct irs_ho *this, const void *addr,
                                 int len, int af);
static struct hostent * ho_next(struct irs_ho *this);
static void             ho_rewind(struct irs_ho *this);
static void             ho_minimize(struct irs_ho *this);
static struct __res_state * ho_res_get(struct irs_ho *this);
static void             ho_res_set(struct irs_ho *this,
                                  struct __res_state *res,
                                  void (*free_res)(void *));
static struct addrinfo * ho_addrinfo(struct irs_ho *this, const char *name,
                                    const struct addrinfo *pai);

static size_t           ns_namelen(const char *);
static int              init(struct irs_ho *this);

/* Portability. */

#ifndef SEEK_SET
# define SEEK_SET 0
#endif

/* Public. */

struct irs_ho *
irs_lcl_ho(struct irs_acc *this) {
       struct irs_ho *ho;
       struct pvt *pvt;

       UNUSED(this);

       if (!(pvt = memget(sizeof *pvt))) {
               errno = ENOMEM;
               return (NULL);
       }
       memset(pvt, 0, sizeof *pvt);
       if (!(ho = memget(sizeof *ho))) {
               memput(pvt, sizeof *pvt);
               errno = ENOMEM;
               return (NULL);
       }
       memset(ho, 0x5e, sizeof *ho);
       ho->private = pvt;
       ho->close = ho_close;
       ho->byname = ho_byname;
       ho->byname2 = ho_byname2;
       ho->byaddr = ho_byaddr;
       ho->next = ho_next;
       ho->rewind = ho_rewind;
       ho->minimize = ho_minimize;
       ho->res_get = ho_res_get;
       ho->res_set = ho_res_set;
       ho->addrinfo = ho_addrinfo;
       return (ho);
}

/* Methods. */

static void
ho_close(struct irs_ho *this) {
       struct pvt *pvt = (struct pvt *)this->private;

       ho_minimize(this);
       if (pvt->fp)
               (void) fclose(pvt->fp);
       if (pvt->res && pvt->free_res)
               (*pvt->free_res)(pvt->res);
       memput(pvt, sizeof *pvt);
       memput(this, sizeof *this);
}

static struct hostent *
ho_byname(struct irs_ho *this, const char *name) {
       struct pvt *pvt = (struct pvt *)this->private;
       struct hostent *hp;

       if (init(this) == -1)
               return (NULL);

       if (pvt->res->options & RES_USE_INET6) {
               hp = ho_byname2(this, name, AF_INET6);
               if (hp)
                       return (hp);
       }
       return (ho_byname2(this, name, AF_INET));
}

static struct hostent *
ho_byname2(struct irs_ho *this, const char *name, int af) {
       struct pvt *pvt = (struct pvt *)this->private;
       struct hostent *hp;
       char **hap;
       size_t n;

       if (init(this) == -1)
               return (NULL);

       ho_rewind(this);
       n = ns_namelen(name);
       while ((hp = ho_next(this)) != NULL) {
               size_t nn;

               if (hp->h_addrtype != af)
                       continue;
               nn = ns_namelen(hp->h_name);
               if (strncasecmp(hp->h_name, name, Max(n, nn)) == 0)
                       goto found;
               for (hap = hp->h_aliases; *hap; hap++) {
                       nn = ns_namelen(*hap);
                       if (strncasecmp(*hap, name, Max(n, nn)) == 0)
                               goto found;
               }
       }
found:
       if (!hp) {
               RES_SET_H_ERRNO(pvt->res, HOST_NOT_FOUND);
               return (NULL);
       }
       RES_SET_H_ERRNO(pvt->res, NETDB_SUCCESS);
       return (hp);
}

static struct hostent *
ho_byaddr(struct irs_ho *this, const void *addr, int len, int af) {
       struct pvt *pvt = (struct pvt *)this->private;
       const u_char *uaddr = addr;
       struct hostent *hp;
       int size;

       if (init(this) == -1)
               return (NULL);

       if (af == AF_INET6 && len == IN6ADDRSZ &&
           (!memcmp(uaddr, mapped, sizeof mapped) ||
            !memcmp(uaddr, tunnelled, sizeof tunnelled))) {
               /* Unmap. */
               addr = (const u_char *)addr + sizeof mapped;
               uaddr += sizeof mapped;
               af = AF_INET;
               len = INADDRSZ;
       }
       switch (af) {
       case AF_INET:
               size = INADDRSZ;
               break;
       case AF_INET6:
               size = IN6ADDRSZ;
               break;
       default:
               errno = EAFNOSUPPORT;
               RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
               return (NULL);
       }
       if (size > len) {
               errno = EINVAL;
               RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
               return (NULL);
       }

       /*
        * Do the search.
        */
       ho_rewind(this);
       while ((hp = ho_next(this)) != NULL) {
               char **hap;

               for (hap = hp->h_addr_list; *hap; hap++) {
                       const u_char *taddr = (const u_char *)*hap;
                       int taf = hp->h_addrtype;
                       int tlen = hp->h_length;

                       if (taf == AF_INET6 && tlen == IN6ADDRSZ &&
                           (!memcmp(taddr, mapped, sizeof mapped) ||
                            !memcmp(taddr, tunnelled, sizeof tunnelled))) {
                               /* Unmap. */
                               taddr += sizeof mapped;
                               taf = AF_INET;
                               tlen = INADDRSZ;
                       }
                       if (taf == af && tlen == len &&
                           !memcmp(taddr, uaddr, tlen))
                               goto found;
               }
       }
found:
       if (!hp) {
               RES_SET_H_ERRNO(pvt->res, HOST_NOT_FOUND);
               return (NULL);
       }
       RES_SET_H_ERRNO(pvt->res, NETDB_SUCCESS);
       return (hp);
}

static struct hostent *
ho_next(struct irs_ho *this) {
       struct pvt *pvt = (struct pvt *)this->private;
       char *cp, **q, *p;
       char *bufp, *ndbuf, *dbuf = NULL;
       int c, af, len, bufsiz, offset;

       if (init(this) == -1)
               return (NULL);

       if (!pvt->fp)
               ho_rewind(this);
       if (!pvt->fp) {
               RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
               return (NULL);
       }
       bufp = pvt->hostbuf;
       bufsiz = sizeof pvt->hostbuf;
       offset = 0;
again:
       if (!(p = fgets(bufp + offset, bufsiz - offset, pvt->fp))) {
               RES_SET_H_ERRNO(pvt->res, HOST_NOT_FOUND);
               if (dbuf)
                       free(dbuf);
               return (NULL);
       }
       if (!strchr(p, '\n') && !feof(pvt->fp)) {
#define GROWBUF 1024
               /* allocate space for longer line */
               if (dbuf == NULL) {
                       if ((ndbuf = malloc(bufsiz + GROWBUF)) != NULL)
                               strcpy(ndbuf, bufp);
               } else
                       ndbuf = realloc(dbuf, bufsiz + GROWBUF);
               if (ndbuf) {
                       dbuf = ndbuf;
                       bufp = dbuf;
                       bufsiz += GROWBUF;
                       offset = strlen(dbuf);
               } else {
                       /* allocation failed; skip this long line */
                       while ((c = getc(pvt->fp)) != EOF)
                               if (c == '\n')
                                       break;
                       if (c != EOF)
                               ungetc(c, pvt->fp);
               }
               goto again;
       }

       p -= offset;
       offset = 0;

       if (*p == '#')
               goto again;
       if ((cp = strpbrk(p, "#\n")) != NULL)
               *cp = '\0';
       if (!(cp = strpbrk(p, " \t")))
               goto again;
       *cp++ = '\0';
       if (inet_pton(AF_INET6, p, pvt->host_addr) > 0) {
               af = AF_INET6;
               len = IN6ADDRSZ;
       } else if (inet_aton(p, (struct in_addr *)pvt->host_addr) > 0) {
               if (pvt->res->options & RES_USE_INET6) {
                       map_v4v6_address((char*)pvt->host_addr,
                                        (char*)pvt->host_addr);
                       af = AF_INET6;
                       len = IN6ADDRSZ;
               } else {
                       af = AF_INET;
                       len = INADDRSZ;
               }
       } else {
               goto again;
       }
       pvt->h_addr_ptrs[0] = (char *)pvt->host_addr;
       pvt->h_addr_ptrs[1] = NULL;
       pvt->host.h_addr_list = pvt->h_addr_ptrs;
       pvt->host.h_length = len;
       pvt->host.h_addrtype = af;
       while (*cp == ' ' || *cp == '\t')
               cp++;
       pvt->host.h_name = cp;
       q = pvt->host.h_aliases = pvt->host_aliases;
       if ((cp = strpbrk(cp, " \t")) != NULL)
               *cp++ = '\0';
       while (cp && *cp) {
               if (*cp == ' ' || *cp == '\t') {
                       cp++;
                       continue;
               }
               if (q < &pvt->host_aliases[MAXALIASES - 1])
                       *q++ = cp;
               if ((cp = strpbrk(cp, " \t")) != NULL)
                       *cp++ = '\0';
       }
       *q = NULL;
       if (dbuf)
               free(dbuf);
       RES_SET_H_ERRNO(pvt->res, NETDB_SUCCESS);
       return (&pvt->host);
}

static void
ho_rewind(struct irs_ho *this) {
       struct pvt *pvt = (struct pvt *)this->private;

       if (pvt->fp) {
               if (fseek(pvt->fp, 0L, SEEK_SET) == 0)
                       return;
               (void)fclose(pvt->fp);
       }
       if (!(pvt->fp = fopen(_PATH_HOSTS, "r")))
               return;
       if (fcntl(fileno(pvt->fp), F_SETFD, 1) < 0) {
               (void)fclose(pvt->fp);
               pvt->fp = NULL;
       }
}

static void
ho_minimize(struct irs_ho *this) {
       struct pvt *pvt = (struct pvt *)this->private;

       if (pvt->fp != NULL) {
               (void)fclose(pvt->fp);
               pvt->fp = NULL;
       }
       if (pvt->res)
               res_nclose(pvt->res);
}

static struct __res_state *
ho_res_get(struct irs_ho *this) {
       struct pvt *pvt = (struct pvt *)this->private;

       if (!pvt->res) {
               struct __res_state *res;
               res = (struct __res_state *)malloc(sizeof *res);
               if (!res) {
                       errno = ENOMEM;
                       return (NULL);
               }
               memset(res, 0, sizeof *res);
               ho_res_set(this, res, free);
       }

       return (pvt->res);
}

static void
ho_res_set(struct irs_ho *this, struct __res_state *res,
               void (*free_res)(void *)) {
       struct pvt *pvt = (struct pvt *)this->private;

       if (pvt->res && pvt->free_res) {
               res_nclose(pvt->res);
               (*pvt->free_res)(pvt->res);
       }

       pvt->res = res;
       pvt->free_res = free_res;
}

struct lcl_res_target {
       struct lcl_res_target *next;
       int family;
};

/* XXX */
extern struct addrinfo *hostent2addrinfo __P((struct hostent *,
                                             const struct addrinfo *pai));

static struct addrinfo *
ho_addrinfo(struct irs_ho *this, const char *name, const struct addrinfo *pai)
{
       struct pvt *pvt = (struct pvt *)this->private;
       struct hostent *hp;
       struct lcl_res_target q, q2, *p;
       struct addrinfo sentinel, *cur;

       memset(&q, 0, sizeof(q2));
       memset(&q2, 0, sizeof(q2));
       memset(&sentinel, 0, sizeof(sentinel));
       cur = &sentinel;

       switch(pai->ai_family) {
       case AF_UNSPEC:         /*%< INET6 then INET4 */
               q.family = AF_INET6;
               q.next = &q2;
               q2.family = AF_INET;
               break;
       case AF_INET6:
               q.family = AF_INET6;
               break;
       case AF_INET:
               q.family = AF_INET;
               break;
       default:
               RES_SET_H_ERRNO(pvt->res, NO_RECOVERY); /*%< ??? */
               return(NULL);
       }

       for (p = &q; p; p = p->next) {
               struct addrinfo *ai;

               hp = (*this->byname2)(this, name, p->family);
               if (hp == NULL) {
                       /* byname2 should've set an appropriate error */
                       continue;
               }
               if ((hp->h_name == NULL) || (hp->h_name[0] == 0) ||
                   (hp->h_addr_list[0] == NULL)) {
                       RES_SET_H_ERRNO(pvt->res, NO_RECOVERY);
                       continue;
               }

               ai = hostent2addrinfo(hp, pai);
               if (ai) {
                       cur->ai_next = ai;
                       while (cur->ai_next)
                               cur = cur->ai_next;
               }
       }

       if (sentinel.ai_next == NULL)
               RES_SET_H_ERRNO(pvt->res, HOST_NOT_FOUND);

       return(sentinel.ai_next);
}

/* Private. */

static size_t
ns_namelen(const char *s) {
       int i;

       for (i = strlen(s); i > 0 && s[i-1] == '.'; i--)
               (void)NULL;
       return ((size_t) i);
}

static int
init(struct irs_ho *this) {
       struct pvt *pvt = (struct pvt *)this->private;

       if (!pvt->res && !ho_res_get(this))
               return (-1);
       if (((pvt->res->options & RES_INIT) == 0U) &&
           res_ninit(pvt->res) == -1)
               return (-1);
       return (0);
}

/*! \file */

You are viewing proxied material from ftp.icm.edu.pl. The copyright of proxied material belongs to its original authors. Any comments or complaints in relation to proxied material should be directed to the original authors of the content concerned. Please see the disclaimer for more details.