diff options
Diffstat (limited to 'usr.sbin/ypserv/yp_dnslookup.c')
| -rw-r--r-- | usr.sbin/ypserv/yp_dnslookup.c | 551 |
1 files changed, 0 insertions, 551 deletions
diff --git a/usr.sbin/ypserv/yp_dnslookup.c b/usr.sbin/ypserv/yp_dnslookup.c deleted file mode 100644 index 4ea6a13..0000000 --- a/usr.sbin/ypserv/yp_dnslookup.c +++ /dev/null @@ -1,551 +0,0 @@ -/* - * Copyright (c) 1995, 1996 - * Bill Paul <wpaul@ctr.columbia.edu>. 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 Bill Paul. - * 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 Bill Paul 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 Bill Paul 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/cdefs.h> -__FBSDID("$FreeBSD$"); - -/* - * Do standard and reverse DNS lookups using the resolver library. - * Take care of all the dirty work here so the main program only has to - * pass us a pointer to an array of characters. - * - * We have to use direct resolver calls here otherwise the YP server - * could end up looping by calling itself over and over again until - * it disappeared up its own belly button. - */ - -#include <sys/param.h> -#include <sys/socket.h> -#include <sys/time.h> -#include <sys/fcntl.h> -#include <sys/queue.h> -#include <netinet/in.h> -#include <arpa/inet.h> -#include <arpa/nameser.h> - -#include <ctype.h> -#include <errno.h> -#include <netdb.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <resolv.h> -#include <unistd.h> - -#include <rpcsvc/yp.h> -#include "yp_extern.h" - -static char * -parse(struct hostent *hp) -{ - static char result[MAXHOSTNAMELEN * 2]; - int i; - size_t len; - char addr[46]; - - if (hp == NULL) - return(NULL); - - if (inet_ntop(hp->h_addrtype, hp->h_addr, addr, sizeof(addr)) == NULL) - return(NULL); - - len = strlen(addr) + 1 + strlen(hp->h_name); - for (i = 0; hp->h_aliases[i]; i++) - len += strlen(hp->h_aliases[i]) + 1; - len++; - - if (len > sizeof(result)) - return(NULL); - - bzero(result, sizeof(result)); - snprintf(result, sizeof(result), "%s %s", addr, hp->h_name); - for (i = 0; hp->h_aliases[i]; i++) { - strcat(result, " "); - strcat(result, hp->h_aliases[i]); - } - - return ((char *)&result); -} - -#define MAXPACKET (64*1024) -#define DEF_TTL 50 - -#define BY_DNS_ID 1 -#define BY_RPC_XID 2 - -extern struct hostent *__dns_getanswer(char *, int, char *, int); - -static TAILQ_HEAD(dns_qhead, circleq_dnsentry) qhead; - -struct circleq_dnsentry { - SVCXPRT *xprt; - unsigned long xid; - struct sockaddr_in client_addr; - unsigned long ypvers; - unsigned long id; - unsigned long ttl; - unsigned long type; - unsigned short prot_type; - char **domain; - char *name; - int addrtype; - int addrlen; - uint32_t addr[4]; /* IPv4 or IPv6 */ - TAILQ_ENTRY(circleq_dnsentry) links; -}; - -static int pending = 0; - -int -yp_init_resolver(void) -{ - TAILQ_INIT(&qhead); - if (!(_res.options & RES_INIT) && res_init() == -1) { - yp_error("res_init failed"); - return(1); - } - if ((resfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1) { - yp_error("couldn't create socket"); - return(1); - } - if (fcntl(resfd, F_SETFL, O_NONBLOCK) == -1) { - yp_error("couldn't make resolver socket non-blocking"); - return(1); - } - return(0); -} - -static struct -circleq_dnsentry *yp_malloc_dnsent(void) -{ - register struct circleq_dnsentry *q; - - q = (struct circleq_dnsentry *)malloc(sizeof(struct circleq_dnsentry)); - - if (q == NULL) { - yp_error("failed to malloc() circleq dns entry"); - return(NULL); - } - - return(q); -} - -/* - * Transmit a query. - */ -static unsigned long -yp_send_dns_query(char *name, int type) -{ - char buf[MAXPACKET]; - int n; - HEADER *hptr; - int ns; - int rval; - unsigned long id; - - bzero(buf, sizeof(buf)); - - n = res_mkquery(QUERY,name,C_IN,type,NULL,0,NULL,buf,sizeof(buf)); - - if (n <= 0) { - yp_error("res_mkquery failed for %s type %d", name, type); - return(0); - } - - hptr = (HEADER *)&buf; - id = ntohs(hptr->id); - - for (ns = 0; ns < _res.nscount; ns++) { - rval = sendto(resfd, buf, n, 0, - (struct sockaddr *)&_res.nsaddr_list[ns], - sizeof(struct sockaddr)); - if (rval == -1) { - yp_error("sendto failed"); - return(0); - } - } - - return(id); -} - -static struct circleq_dnsentry * -yp_find_dnsqent(unsigned long id, int type) -{ - register struct circleq_dnsentry *q; - - TAILQ_FOREACH(q, &qhead, links) { - switch (type) { - case BY_RPC_XID: - if (id == q->xid) - return(q); - break; - case BY_DNS_ID: - default: - if (id == q->id) - return(q); - break; - } - } - return (NULL); -} - -static void -yp_send_dns_reply(struct circleq_dnsentry *q, char *buf) -{ - ypresponse result_v1; - ypresp_val result_v2; - unsigned long xid; - struct sockaddr_in client_addr; - xdrproc_t xdrfunc; - char *result; - - /* - * Set up correct reply struct and - * XDR filter depending on ypvers. - */ - switch (q->ypvers) { - case YPVERS: - bzero((char *)&result_v2, sizeof(result_v2)); - - if (buf == NULL) - result_v2.stat = YP_NOKEY; - else { - result_v2.val.valdat_len = strlen(buf); - result_v2.val.valdat_val = buf; - result_v2.stat = YP_TRUE; - } - result = (char *)&result_v2; - xdrfunc = (xdrproc_t)xdr_ypresp_val; - break; - case YPOLDVERS: - /* - * The odds are we will _never_ execute this - * particular code, but we include it anyway - * for the sake of completeness. - */ - bzero((char *)&result_v1, sizeof(result_v1)); - result_v1.yp_resptype = YPRESP_VAL; - -#define YPVAL ypresponse_u.yp_resp_valtype - if (buf == NULL) - result_v1.YPVAL.stat = YP_NOKEY; - else { - result_v1.YPVAL.val.valdat_len = strlen(buf); - result_v1.YPVAL.val.valdat_val = buf; - result_v1.YPVAL.stat = YP_TRUE; - } - result = (char *)&result_v1; - xdrfunc = (xdrproc_t)xdr_ypresponse; - break; - default: - yp_error("bad YP program version (%lu)!", q->ypvers); - return; - break; - } - - if (debug) - yp_error("sending dns reply to %s (%lu)", - inet_ntoa(q->client_addr.sin_addr), q->id); - /* - * XXX This is disgusting. There's basically one transport - * handle for UDP, but we're holding off on replying to a - * client until we're ready, by which time we may have received - * several other queries from other clients with different - * transaction IDs. So to make the delayed response thing work, - * we have to save the transaction ID and client address of - * each request, then jam them into the transport handle when - * we're ready to send a reply. Then after we've send the reply, - * we put the old transaction ID and remote address back the - * way we found 'em. This is _INCREDIBLY_ non-portable; it's - * not even supported by the RPC library. - */ - /* - * XXX Don't frob the transaction ID for TCP handles. - */ - if (q->prot_type == SOCK_DGRAM) - xid = svcudp_set_xid(q->xprt, q->xid); - client_addr = q->xprt->xp_raddr; - q->xprt->xp_raddr = q->client_addr; - - if (!svc_sendreply(q->xprt, xdrfunc, result)) - yp_error("svc_sendreply failed"); - - /* - * Now that we sent the reply, - * put the handle back the way it was. - */ - if (q->prot_type == SOCK_DGRAM) - svcudp_set_xid(q->xprt, xid); - q->xprt->xp_raddr = client_addr; - - return; -} - -/* - * Decrement TTL on all queue entries, possibly nuking - * any that have been around too long without being serviced. - */ -void -yp_prune_dnsq(void) -{ - register struct circleq_dnsentry *q, *n; - - q = TAILQ_FIRST(&qhead); - while (q != NULL) { - q->ttl--; - n = TAILQ_NEXT(q, links); - if (!q->ttl) { - TAILQ_REMOVE(&qhead, q, links); - free(q->name); - free(q); - pending--; - } - q = n; - } - - if (pending < 0) - pending = 0; - - return; -} - -/* - * Data is pending on the DNS socket; check for valid replies - * to our queries and dispatch them to waiting clients. - */ -void -yp_run_dnsq(void) -{ - register struct circleq_dnsentry *q; - char buf[sizeof(HEADER) + MAXPACKET]; - struct sockaddr_in sin; - socklen_t len; - int rval; - HEADER *hptr; - struct hostent *hent; - - if (debug) - yp_error("running dns queue"); - - bzero(buf, sizeof(buf)); - - len = sizeof(struct sockaddr_in); - rval = recvfrom(resfd, buf, sizeof(buf), 0, - (struct sockaddr *)&sin, &len); - - if (rval == -1) { - yp_error("recvfrom failed: %s", strerror(errno)); - return; - } - - /* - * We may have data left in the socket that represents - * replies to earlier queries that we don't care about - * anymore. If there are no lookups pending or the packet - * ID doesn't match any of the queue IDs, just drop it - * on the floor. - */ - hptr = (HEADER *)&buf; - if (!pending || - (q = yp_find_dnsqent(ntohs(hptr->id), BY_DNS_ID)) == NULL) { - /* ignore */ - return; - } - - if (debug) - yp_error("got dns reply from %s", inet_ntoa(sin.sin_addr)); - - hent = __dns_getanswer(buf, rval, q->name, q->type); - - if (hent != NULL) { - if (q->type == T_PTR) { - hent->h_addr = (char *)q->addr; - hent->h_addrtype = q->addrtype; - hent->h_length = q->addrlen; - } - } - - /* Got an answer ready for a client -- send it off. */ - yp_send_dns_reply(q, parse(hent)); - pending--; - TAILQ_REMOVE(&qhead, q, links); - free(q->name); - free(q); - - /* Decrement TTLs on other entries while we're here. */ - yp_prune_dnsq(); - - return; -} - -/* - * Queue and transmit an asynchronous DNS hostname lookup. - */ -ypstat -yp_async_lookup_name(struct svc_req *rqstp, char *name, int af) -{ - register struct circleq_dnsentry *q; - socklen_t len; - int type; - - /* Check for SOCK_DGRAM or SOCK_STREAM -- we need to know later */ - type = -1; - len = sizeof(type); - if (getsockopt(rqstp->rq_xprt->xp_fd, SOL_SOCKET, - SO_TYPE, &type, &len) == -1) { - yp_error("getsockopt failed: %s", strerror(errno)); - return(YP_YPERR); - } - - /* Avoid transmitting dupe requests. */ - if (type == SOCK_DGRAM && - yp_find_dnsqent(svcudp_get_xid(rqstp->rq_xprt),BY_RPC_XID) != NULL) - return(YP_TRUE); - - if ((q = yp_malloc_dnsent()) == NULL) - return(YP_YPERR); - - q->type = (af == AF_INET) ? T_A : T_AAAA; - q->ttl = DEF_TTL; - q->xprt = rqstp->rq_xprt; - q->ypvers = rqstp->rq_vers; - q->prot_type = type; - if (q->prot_type == SOCK_DGRAM) - q->xid = svcudp_get_xid(q->xprt); - q->client_addr = q->xprt->xp_raddr; - q->domain = _res.dnsrch; - q->id = yp_send_dns_query(name, q->type); - - if (q->id == 0) { - yp_error("DNS query failed"); - free(q); - return(YP_YPERR); - } - - q->name = strdup(name); - TAILQ_INSERT_HEAD(&qhead, q, links); - pending++; - - if (debug) - yp_error("queueing async DNS name lookup (%d)", q->id); - - yp_prune_dnsq(); - return(YP_TRUE); -} - -/* - * Queue and transmit an asynchronous DNS IP address lookup. - */ -ypstat -yp_async_lookup_addr(struct svc_req *rqstp, char *addr, int af) -{ - register struct circleq_dnsentry *q; - char buf[MAXHOSTNAMELEN], *qp; - uint32_t abuf[4]; /* IPv4 or IPv6 */ - u_char *uaddr = (u_char *)abuf; - socklen_t len; - int type, n; - - /* Check for SOCK_DGRAM or SOCK_STREAM -- we need to know later */ - type = -1; - len = sizeof(type); - if (getsockopt(rqstp->rq_xprt->xp_fd, SOL_SOCKET, - SO_TYPE, &type, &len) == -1) { - yp_error("getsockopt failed: %s", strerror(errno)); - return(YP_YPERR); - } - - /* Avoid transmitting dupe requests. */ - if (type == SOCK_DGRAM && - yp_find_dnsqent(svcudp_get_xid(rqstp->rq_xprt),BY_RPC_XID) != NULL) - return(YP_TRUE); - - if ((q = yp_malloc_dnsent()) == NULL) - return(YP_YPERR); - - switch (af) { - case AF_INET: - if (inet_aton(addr, (struct in_addr *)uaddr) != 1) - return(YP_NOKEY); - snprintf(buf, sizeof(buf), "%u.%u.%u.%u.in-addr.arpa", - (uaddr[3] & 0xff), (uaddr[2] & 0xff), - (uaddr[1] & 0xff), (uaddr[0] & 0xff)); - len = INADDRSZ; - break; - case AF_INET6: - if (inet_pton(af, addr, uaddr) != 1) - return(YP_NOKEY); - qp = buf; - for (n = IN6ADDRSZ - 1; n >= 0; n--) { - qp += (size_t)sprintf(qp, "%x.%x.", uaddr[n] & 0xf, - (uaddr[n] >> 4) & 0xf); - } - strlcat(buf, "ip6.arpa", sizeof(buf)); - len = IN6ADDRSZ; - break; - default: - return(YP_YPERR); - } - - if (debug) - yp_error("DNS address is: %s", buf); - - q->type = T_PTR; - q->ttl = DEF_TTL; - q->xprt = rqstp->rq_xprt; - q->ypvers = rqstp->rq_vers; - q->domain = NULL; - q->prot_type = type; - if (q->prot_type == SOCK_DGRAM) - q->xid = svcudp_get_xid(q->xprt); - q->client_addr = q->xprt->xp_raddr; - q->id = yp_send_dns_query(buf, q->type); - - if (q->id == 0) { - yp_error("DNS query failed"); - free(q); - return(YP_YPERR); - } - - memcpy(q->addr, uaddr, len); - q->addrlen = len; - q->addrtype = af; - q->name = strdup(buf); - TAILQ_INSERT_HEAD(&qhead, q, links); - pending++; - - if (debug) - yp_error("queueing async DNS address lookup (%d)", q->id); - - yp_prune_dnsq(); - return(YP_TRUE); -} |
