| /* $NetBSD: sethostent.c,v 1.20 2014/03/17 13:24:23 christos Exp $ */ |
| |
| /* |
| * Copyright (c) 1985, 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 <arpa/inet.h> |
| #include <arpa/nameser.h> |
| #include <assert.h> |
| #include <errno.h> |
| #include <netdb.h> |
| #include <netinet/in.h> |
| #include <resolv.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/param.h> |
| |
| #include "hostent.h" |
| #include "resolv_private.h" |
| |
| constexpr int MAXALIASES = 35; |
| constexpr int MAXADDRS = 35; |
| |
| static void sethostent_r(FILE** hf) { |
| if (!*hf) |
| *hf = fopen(_PATH_HOSTS, "re"); |
| else |
| rewind(*hf); |
| } |
| |
| static void endhostent_r(FILE** hf) { |
| if (*hf) { |
| (void) fclose(*hf); |
| *hf = NULL; |
| } |
| } |
| |
| // TODO: Consider returning a boolean result as files_getaddrinfo() does because the error code |
| // does not currently return to netd. |
| int _hf_gethtbyname2(const char* name, int af, getnamaddr* info) { |
| struct hostent *hp, hent; |
| char *buf, *ptr; |
| size_t len, num, i; |
| char* aliases[MAXALIASES]; |
| char* addr_ptrs[MAXADDRS]; |
| |
| FILE* hf = NULL; |
| sethostent_r(&hf); |
| if (hf == NULL) { |
| // TODO: Consider converting to a private extended EAI_* error code. |
| // Currently, the EAI_* value has no corresponding error code for invalid argument socket |
| // length. In order to not rely on errno, convert the original error code pair, EAI_SYSTEM |
| // and EINVAL, to EAI_FAIL. |
| return EAI_FAIL; |
| } |
| |
| if ((ptr = buf = (char*) malloc(len = info->buflen)) == NULL) { |
| return EAI_MEMORY; |
| } |
| |
| hent.h_name = NULL; |
| hent.h_addrtype = 0; |
| hent.h_length = 0; |
| |
| size_t anum = 0; |
| for (num = 0; num < MAXADDRS; /**/) { |
| info->hp->h_addrtype = af; |
| info->hp->h_length = 0; |
| |
| int he; |
| hp = netbsd_gethostent_r(hf, info->hp, info->buf, info->buflen, &he); |
| if (hp == NULL) { |
| if (he == NETDB_INTERNAL && errno == ENOSPC) { |
| goto nospc; // glibc compatibility. |
| } |
| break; |
| } |
| |
| if (strcasecmp(hp->h_name, name) != 0) { |
| char** cp; |
| for (cp = hp->h_aliases; *cp != NULL; cp++) |
| if (strcasecmp(*cp, name) == 0) break; |
| // NOTE: does not increment num |
| if (*cp == NULL) continue; |
| } |
| |
| if (num == 0) { |
| hent.h_addrtype = hp->h_addrtype; |
| hent.h_length = hp->h_length; |
| |
| HENT_SCOPY(hent.h_name, hp->h_name, ptr, len); |
| for (anum = 0; hp->h_aliases[anum]; anum++) { |
| if (anum >= MAXALIASES) goto nospc; |
| HENT_SCOPY(aliases[anum], hp->h_aliases[anum], ptr, len); |
| } |
| ptr = align_ptr(ptr); |
| if ((size_t)(ptr - buf) >= info->buflen) goto nospc; |
| } |
| |
| if (num >= MAXADDRS) goto nospc; |
| HENT_COPY(addr_ptrs[num], hp->h_addr_list[0], hp->h_length, ptr, len); |
| |
| num++; |
| } |
| endhostent_r(&hf); |
| |
| if (num == 0) { |
| free(buf); |
| // TODO: Perhaps convert HOST_NOT_FOUND to EAI_NONAME instead. |
| // The original return error number is h_errno HOST_NOT_FOUND which was converted to |
| // EAI_NODATA. |
| return EAI_NODATA; |
| } |
| |
| hp = info->hp; |
| ptr = info->buf; |
| len = info->buflen; |
| |
| hp->h_addrtype = hent.h_addrtype; |
| hp->h_length = hent.h_length; |
| |
| HENT_ARRAY(hp->h_aliases, anum, ptr, len); |
| HENT_ARRAY(hp->h_addr_list, num, ptr, len); |
| |
| for (i = 0; i < num; i++) { |
| HENT_COPY(hp->h_addr_list[i], addr_ptrs[i], hp->h_length, ptr, len); |
| |
| // reserve space for mapping IPv4 address to IPv6 address in place |
| if (hp->h_addrtype == AF_INET) { |
| HENT_COPY(ptr, NAT64_PAD, sizeof(NAT64_PAD), ptr, len); |
| } |
| } |
| hp->h_addr_list[num] = NULL; |
| |
| HENT_SCOPY(hp->h_name, hent.h_name, ptr, len); |
| |
| for (i = 0; i < anum; i++) { |
| HENT_SCOPY(hp->h_aliases[i], aliases[i], ptr, len); |
| } |
| hp->h_aliases[anum] = NULL; |
| |
| free(buf); |
| return 0; |
| nospc: |
| free(buf); |
| return EAI_MEMORY; |
| } |
| |
| // TODO: Consider returning a boolean result as files_getaddrinfo() does because the error code |
| // does not currently return to netd. |
| int _hf_gethtbyaddr(const unsigned char* uaddr, int len, int af, getnamaddr* info) { |
| info->hp->h_length = len; |
| info->hp->h_addrtype = af; |
| |
| FILE* hf = NULL; |
| sethostent_r(&hf); |
| if (hf == NULL) { |
| // TODO: Consider converting to a private extended EAI_* error code. |
| // Currently, the EAI_* value has no corresponding error code for invalid argument socket |
| // length. In order to not rely on errno, convert the original error code pair, EAI_SYSTEM |
| // and EINVAL, to EAI_FAIL. |
| return EAI_FAIL; |
| } |
| struct hostent* hp; |
| int he; |
| while ((hp = netbsd_gethostent_r(hf, info->hp, info->buf, info->buflen, &he)) != NULL) |
| if (!memcmp(hp->h_addr_list[0], uaddr, (size_t) hp->h_length)) break; |
| endhostent_r(&hf); |
| |
| if (hp == NULL) { |
| if (errno == ENOSPC) return EAI_MEMORY; // glibc compatibility. |
| // TODO: Perhaps convert HOST_NOT_FOUND to EAI_NONAME instead. |
| // The original return error number is h_errno HOST_NOT_FOUND which was converted to |
| // EAI_NODATA. |
| return EAI_NODATA; |
| } |
| return 0; |
| } |