diff options
Diffstat (limited to 'lib/libc/net/getnetbydns.c')
| -rw-r--r-- | lib/libc/net/getnetbydns.c | 465 |
1 files changed, 465 insertions, 0 deletions
diff --git a/lib/libc/net/getnetbydns.c b/lib/libc/net/getnetbydns.c new file mode 100644 index 0000000..23c9c45 --- /dev/null +++ b/lib/libc/net/getnetbydns.c @@ -0,0 +1,465 @@ +/*- + * 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. + * - + * Portions Copyright (c) 1993 by Digital Equipment Corporation. + * + * 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, and that + * the name of Digital Equipment Corporation not be used in advertising or + * publicity pertaining to distribution of the document or software without + * specific, written prior permission. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL + * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT + * CORPORATION 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. + * - + * --Copyright-- + */ +/* Portions Copyright (c) 1993 Carlos Leandro and Rui Salgueiro + * Dep. Matematica Universidade de Coimbra, Portugal, Europe + * + * 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. + */ + +#if defined(LIBC_SCCS) && !defined(lint) +static char sccsid[] = "@(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93"; +#endif /* LIBC_SCCS and not lint */ +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/inet.h> +#include <arpa/nameser.h> + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <netdb.h> +#include <resolv.h> +#include <ctype.h> +#include <string.h> +#include <unistd.h> +#include <syslog.h> +#include <stdarg.h> +#include <nsswitch.h> + +#include "netdb_private.h" +#include "res_config.h" + +#define BYADDR 0 +#define BYNAME 1 + +#define MAXPACKET (64*1024) + +typedef union { + HEADER hdr; + u_char buf[MAXPACKET]; +} querybuf; + +typedef union { + long al; + char ac; +} align; + +/* + * Reverse the order of first four dotted entries of in. + * Out must contain space for at least strlen(in) characters. + * The result does not include any leading 0s of in. + */ +static void +ipreverse(char *in, char *out) +{ + char *pos[4]; + int len[4]; + char *p, *start; + int i = 0; + int leading = 1; + + /* Fill-in element positions and lengths: pos[], len[]. */ + start = p = in; + for (;;) { + if (*p == '.' || *p == '\0') { + /* Leading 0? */ + if (leading && p - start == 1 && *start == '0') + len[i] = 0; + else { + len[i] = p - start; + leading = 0; + } + pos[i] = start; + start = p + 1; + i++; + } + if (i == 4) + break; + if (*p == 0) { + for (; i < 4; i++) { + pos[i] = p; + len[i] = 0; + } + break; + } + p++; + } + + /* Copy the entries in reverse order */ + p = out; + leading = 1; + for (i = 3; i >= 0; i--) { + memcpy(p, pos[i], len[i]); + if (len[i]) + leading = 0; + p += len[i]; + /* Need a . separator? */ + if (!leading && i > 0 && len[i - 1]) + *p++ = '.'; + } + *p = '\0'; +} + +static int +getnetanswer(querybuf *answer, int anslen, int net_i, struct netent *ne, + struct netent_data *ned, res_state statp) +{ + + HEADER *hp; + u_char *cp; + int n; + u_char *eom; + int type, class, ancount, qdcount, haveanswer; + char aux[MAXHOSTNAMELEN]; + char ans[MAXHOSTNAMELEN]; + char *in, *bp, *ep, **ap; + + /* + * find first satisfactory answer + * + * answer --> +------------+ ( MESSAGE ) + * | Header | + * +------------+ + * | Question | the question for the name server + * +------------+ + * | Answer | RRs answering the question + * +------------+ + * | Authority | RRs pointing toward an authority + * | Additional | RRs holding additional information + * +------------+ + */ + eom = answer->buf + anslen; + hp = &answer->hdr; + ancount = ntohs(hp->ancount); /* #/records in the answer section */ + qdcount = ntohs(hp->qdcount); /* #/entries in the question section */ + bp = ned->netbuf; + ep = ned->netbuf + sizeof(ned->netbuf); + cp = answer->buf + HFIXEDSZ; + if (!qdcount) { + if (hp->aa) + RES_SET_H_ERRNO(statp, HOST_NOT_FOUND); + else + RES_SET_H_ERRNO(statp, TRY_AGAIN); + return (-1); + } + while (qdcount-- > 0) + cp += __dn_skipname(cp, eom) + QFIXEDSZ; + ap = ned->net_aliases; + *ap = NULL; + ne->n_aliases = ned->net_aliases; + haveanswer = 0; + while (--ancount >= 0 && cp < eom) { + n = dn_expand(answer->buf, eom, cp, bp, ep - bp); + if ((n < 0) || !res_dnok(bp)) + break; + cp += n; + ans[0] = '\0'; + (void)strncpy(&ans[0], bp, sizeof(ans) - 1); + ans[sizeof(ans) - 1] = '\0'; + GETSHORT(type, cp); + GETSHORT(class, cp); + cp += INT32SZ; /* TTL */ + GETSHORT(n, cp); + if (class == C_IN && type == T_PTR) { + n = dn_expand(answer->buf, eom, cp, bp, ep - bp); + if ((n < 0) || !res_hnok(bp)) { + cp += n; + return (-1); + } + cp += n; + *ap++ = bp; + n = strlen(bp) + 1; + bp += n; + ne->n_addrtype = (class == C_IN) ? AF_INET : AF_UNSPEC; + haveanswer++; + } + } + if (haveanswer) { + *ap = NULL; + switch (net_i) { + case BYADDR: + ne->n_name = *ne->n_aliases; + ne->n_net = 0L; + break; + case BYNAME: + in = *ne->n_aliases; + n = strlen(ans) + 1; + if (ep - bp < n) { + RES_SET_H_ERRNO(statp, NETDB_INTERNAL); + errno = ENOBUFS; + return (-1); + } + strlcpy(bp, ans, ep - bp); + ne->n_name = bp; + if (strlen(in) + 1 > sizeof(aux)) { + RES_SET_H_ERRNO(statp, NETDB_INTERNAL); + errno = ENOBUFS; + return (-1); + } + ipreverse(in, aux); + ne->n_net = inet_network(aux); + break; + } + ne->n_aliases++; + return (0); + } + RES_SET_H_ERRNO(statp, TRY_AGAIN); + return (-1); +} + +int +_dns_getnetbyaddr(void *rval, void *cb_data, va_list ap) +{ + uint32_t net; + int net_type; + char *buffer; + size_t buflen; + int *errnop, *h_errnop; + struct netent *nptr, ne; + struct netent_data *ned; + unsigned int netbr[4]; + int nn, anslen, error; + querybuf *buf; + char qbuf[MAXDNAME]; + uint32_t net2; + res_state statp; + + net = va_arg(ap, uint32_t); + net_type = va_arg(ap, int); + nptr = va_arg(ap, struct netent *); + buffer = va_arg(ap, char *); + buflen = va_arg(ap, size_t); + errnop = va_arg(ap, int *); + h_errnop = va_arg(ap, int *); + + statp = __res_state(); + if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) { + RES_SET_H_ERRNO(statp, NETDB_INTERNAL); + *h_errnop = statp->res_h_errno; + return (NS_UNAVAIL); + } + + if ((ned = __netent_data_init()) == NULL) { + RES_SET_H_ERRNO(statp, NETDB_INTERNAL); + *h_errnop = statp->res_h_errno; + return (NS_UNAVAIL); + } + + *((struct netent **)rval) = NULL; + + if (net_type != AF_INET) { + RES_SET_H_ERRNO(statp, NETDB_INTERNAL); + *h_errnop = statp->res_h_errno; + return (NS_UNAVAIL); + } + + for (nn = 4, net2 = net; net2; net2 >>= 8) + netbr[--nn] = net2 & 0xff; + switch (nn) { + case 3: /* Class A */ + sprintf(qbuf, "0.0.0.%u.in-addr.arpa", netbr[3]); + break; + case 2: /* Class B */ + sprintf(qbuf, "0.0.%u.%u.in-addr.arpa", netbr[3], netbr[2]); + break; + case 1: /* Class C */ + sprintf(qbuf, "0.%u.%u.%u.in-addr.arpa", netbr[3], netbr[2], + netbr[1]); + break; + case 0: /* Class D - E */ + sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa", netbr[3], netbr[2], + netbr[1], netbr[0]); + break; + } + if ((buf = malloc(sizeof(*buf))) == NULL) { + RES_SET_H_ERRNO(statp, NETDB_INTERNAL); + *h_errnop = statp->res_h_errno; + return (NS_NOTFOUND); + } + anslen = res_nquery(statp, qbuf, C_IN, T_PTR, (u_char *)buf, + sizeof(*buf)); + if (anslen < 0) { + free(buf); +#ifdef DEBUG + if (statp->options & RES_DEBUG) + printf("res_nsearch failed\n"); +#endif + *h_errnop = statp->res_h_errno; + return (NS_UNAVAIL); + } else if (anslen > sizeof(*buf)) { + free(buf); +#ifdef DEBUG + if (statp->options & RES_DEBUG) + printf("res_nsearch static buffer too small\n"); +#endif + *h_errnop = statp->res_h_errno; + return (NS_UNAVAIL); + } + error = getnetanswer(buf, anslen, BYADDR, &ne, ned, statp); + free(buf); + if (error == 0) { + /* Strip trailing zeros */ + while ((net & 0xff) == 0 && net != 0) + net >>= 8; + ne.n_net = net; + if (__copy_netent(&ne, nptr, buffer, buflen) != 0) { + *h_errnop = statp->res_h_errno; + return (NS_NOTFOUND); + } + *((struct netent **)rval) = nptr; + return (NS_SUCCESS); + } + *h_errnop = statp->res_h_errno; + return (NS_NOTFOUND); +} + +int +_dns_getnetbyname(void *rval, void *cb_data, va_list ap) +{ + const char *net; + char *buffer; + size_t buflen; + int *errnop, *h_errnop; + struct netent *nptr, ne; + struct netent_data *ned; + int anslen, error; + querybuf *buf; + char qbuf[MAXDNAME]; + res_state statp; + + net = va_arg(ap, const char *); + nptr = va_arg(ap, struct netent *); + buffer = va_arg(ap, char *); + buflen = va_arg(ap, size_t); + errnop = va_arg(ap, int *); + h_errnop = va_arg(ap, int *); + + statp = __res_state(); + if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) { + RES_SET_H_ERRNO(statp, NETDB_INTERNAL); + *h_errnop = statp->res_h_errno; + return (NS_UNAVAIL); + } + if ((ned = __netent_data_init()) == NULL) { + RES_SET_H_ERRNO(statp, NETDB_INTERNAL); + *h_errnop = statp->res_h_errno; + return (NS_UNAVAIL); + } + if ((buf = malloc(sizeof(*buf))) == NULL) { + RES_SET_H_ERRNO(statp, NETDB_INTERNAL); + *h_errnop = statp->res_h_errno; + return (NS_NOTFOUND); + } + + *((struct netent **)rval) = NULL; + + strncpy(qbuf, net, sizeof(qbuf) - 1); + qbuf[sizeof(qbuf) - 1] = '\0'; + anslen = res_nsearch(statp, qbuf, C_IN, T_PTR, (u_char *)buf, + sizeof(*buf)); + if (anslen < 0) { + free(buf); +#ifdef DEBUG + if (statp->options & RES_DEBUG) + printf("res_nsearch failed\n"); +#endif + return (NS_UNAVAIL); + } else if (anslen > sizeof(*buf)) { + free(buf); +#ifdef DEBUG + if (statp->options & RES_DEBUG) + printf("res_search static buffer too small\n"); +#endif + return (NS_UNAVAIL); + } + error = getnetanswer(buf, anslen, BYNAME, &ne, ned, statp); + free(buf); + if (error != 0) { + *h_errnop = statp->res_h_errno; + return (NS_NOTFOUND); + } + if (__copy_netent(&ne, nptr, buffer, buflen) != 0) { + *h_errnop = statp->res_h_errno; + return (NS_NOTFOUND); + } + *((struct netent **)rval) = nptr; + return (NS_SUCCESS); +} + +void +_setnetdnsent(int stayopen) +{ + res_state statp; + + statp = __res_state(); + if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) + return; + if (stayopen) + statp->options |= RES_STAYOPEN | RES_USEVC; +} + +void +_endnetdnsent() +{ + res_state statp; + + statp = __res_state(); + statp->options &= ~(RES_STAYOPEN | RES_USEVC); + res_nclose(statp); +} |
