1 /* $OpenBSD: getnetnamadr.c,v 1.9 2015/01/16 16:48:51 deraadt Exp $ */ 2 /* 3 * Copyright (c) 2012 Eric Faurot <eric@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include <sys/param.h> /* ALIGN */ 19 #include <sys/types.h> 20 #include <sys/socket.h> 21 #include <netinet/in.h> 22 #include <netdb.h> 23 24 #include <asr.h> 25 #include <errno.h> 26 #include <resolv.h> 27 #include <stdlib.h> 28 #include <string.h> 29 30 static void _fillnetent(const struct netent *, struct netent *, char *buf, 31 size_t); 32 33 static struct netent _netent; 34 static char _entbuf[4096]; 35 36 static char *_empty[] = { NULL, }; 37 38 static void 39 _fillnetent(const struct netent *e, struct netent *r, char *buf, size_t len) 40 { 41 char **ptr, *end, *pos; 42 size_t n, i; 43 int naliases; 44 45 bzero(buf, len); 46 bzero(r, sizeof(*r)); 47 r->n_aliases = _empty; 48 49 end = buf + len; 50 ptr = (char **)ALIGN(buf); 51 52 if ((char *)ptr >= end) 53 return; 54 55 for (naliases = 0; e->n_aliases[naliases]; naliases++) 56 ; 57 58 r->n_name = NULL; 59 r->n_addrtype = e->n_addrtype; 60 r->n_net = e->n_net; 61 r->n_aliases = ptr; 62 63 pos = (char *)(ptr + (naliases + 1)); 64 if (pos > end) 65 r->n_aliases = _empty; 66 67 n = strlcpy(pos, e->n_name, end - pos); 68 if (n >= end - pos) 69 return; 70 r->n_name = pos; 71 pos += n + 1; 72 73 for (i = 0; i < naliases; i++) { 74 n = strlcpy(pos, e->n_aliases[i], end - pos); 75 if (n >= end - pos) 76 return; 77 r->n_aliases[i] = pos; 78 pos += n + 1; 79 } 80 } 81 82 struct netent * 83 getnetbyname(const char *name) 84 { 85 struct asr_query *as; 86 struct asr_result ar; 87 88 res_init(); 89 90 as = getnetbyname_async(name, NULL); 91 if (as == NULL) { 92 h_errno = NETDB_INTERNAL; 93 return (NULL); 94 } 95 96 asr_run_sync(as, &ar); 97 98 errno = ar.ar_errno; 99 h_errno = ar.ar_h_errno; 100 if (ar.ar_netent == NULL) 101 return (NULL); 102 103 _fillnetent(ar.ar_netent, &_netent, _entbuf, sizeof(_entbuf)); 104 free(ar.ar_netent); 105 106 return (&_netent); 107 } 108 109 struct netent * 110 getnetbyaddr(in_addr_t net, int type) 111 { 112 struct asr_query *as; 113 struct asr_result ar; 114 115 res_init(); 116 117 as = getnetbyaddr_async(net, type, NULL); 118 if (as == NULL) { 119 h_errno = NETDB_INTERNAL; 120 return (NULL); 121 } 122 123 asr_run_sync(as, &ar); 124 125 errno = ar.ar_errno; 126 h_errno = ar.ar_h_errno; 127 if (ar.ar_netent == NULL) 128 return (NULL); 129 130 _fillnetent(ar.ar_netent, &_netent, _entbuf, sizeof(_entbuf)); 131 free(ar.ar_netent); 132 133 return (&_netent); 134 } 135