/* ********************************************************************** *\ * Copyright IBM Corporation 1988,1991 - All Rights Reserved * * For full copyright information see:'andrew/config/COPYRITE' * \* ********************************************************************** */ /* $Disclaimer: * Permission to use, copy, modify, and distribute this software and its * documentation for any purpose is hereby granted without fee, * provided that the above copyright notice appear in all copies and that * both that copyright notice, this permission notice, and the following * disclaimer appear in supporting documentation, and that the names of * IBM, Carnegie Mellon University, and other copyright holders, not be * used in advertising or publicity pertaining to distribution of the software * without specific, written prior permission. * * IBM, CARNEGIE MELLON UNIVERSITY, AND THE OTHER COPYRIGHT HOLDERS * DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING * ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT * SHALL IBM, CARNEGIE MELLON UNIVERSITY, OR ANY OTHER COPYRIGHT HOLDER * BE LIABLE FOR ANY SPECIAL, 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. * $ */ #ifndef NORCSID #define NORCSID static char rcsid[]="$Header: /afs/cs.cmu.edu/project/atk-dist/auis-6.3/overhead/mail/lib/RCS/rsearch.c,v 2.15 1993/08/25 20:34:46 susan Exp $"; #endif /* cptres_search: search for a domain given a query type. * (Useful with Bind distributions predating bind 4.8.) * Returns the query-buffer in which answers are to be found. * Uses the same searching strategy as gethostbyname(). * Thus, this routine can be used to bind host names or * search for MX records for a domain name. */ #include /* strings.h */ #include #ifdef RESOLVER_ENV #include #include #include #include #include #include extern int errno; static int oneTry(dom, sfx, class, type, answer, anslen) char *dom, *sfx; /* domain name and suffix */ int class, type; /* class and type of query */ char *answer; /* buffer to put answer */ int anslen; /* size of answer */ { char buf[PACKETSZ], tryname[2*MAXDNAME + 1]; int n; if (!(_res.options & RES_INIT)) if (res_init() == -1) return(-1); #ifdef DEBUG if (_res.options & RES_DEBUG) printf("cptres_search()\n"); #endif /* DEBUG */ /* append to form a new name to lookup */ strcpy(tryname, dom); if (sfx != NULL) { strcat(tryname, "."); strcat(tryname, sfx); } #ifdef DEBUG if (_res.options & RES_DEBUG) printf("cptres_search: trying name %s\n", tryname); #endif /* DEBUG */ n = res_mkquery(QUERY, tryname, class, type, (char *)NULL, 0, NULL, buf, sizeof(buf)); if (n <= 0) { #ifdef DEBUG if (_res.options & RES_DEBUG) printf("cptres_search: mkquery failed\n"); #endif /* DEBUG */ return (n); } n = res_send(buf, n, answer, anslen); if (n < 0) { #ifdef DEBUG if (_res.options & RES_DEBUG) printf("cptres_search: send error\n"); #endif /* DEBUG */ return (n); } return(n); } static char *myhostalias(name) /* same as hostalias() in gethostnamadr.c, sigh */ register char *name; { register char *C1, *C2; FILE *fp; char *file, *getenv(); char buf[BUFSIZ]; static char abuf[MAXDNAME]; file = getenv("HOSTALIASES"); if (file == NULL || (fp = fopen(file, "r")) == NULL) return (NULL); buf[sizeof(buf) - 1] = '\0'; while (fgets(buf, sizeof(buf), fp)) { for (C1 = buf; *C1 && !isspace(*C1); ++C1); if (!*C1 || *C1 == '\n') break; if (!strncmp(buf, name, C1 - buf)) { while (isspace(*++C1)); if (!*C1) break; for (C2 = C1 + 1; *C2 && !isspace(*C2); ++C2); abuf[sizeof(abuf) - 1] = *C2 = '\0'; (void)strncpy(abuf, C1, sizeof(abuf) - 1); fclose(fp); return (abuf); } } fclose(fp); return (NULL); } /* For each of a sequence of queries, form a query, send it, await a reply. Always use a QUERY operation, no extra data, no extra resource records. Return the size of the response, or -1 for errors. */ cptres_search(name, class, type, answer, anslen) char *name; /* domain name */ int class, type; /* class and type of query */ char *answer; /* buffer to put answer */ int anslen; /* size of answer */ { register char *cp; #ifdef RES_DNSRCH register char **domain; #endif /* RES_DNSRCH */ register HEADER *hp; int n, NumDots; #ifdef CMUCS #undef RES_DEFAULT #define RES_DEFAULT (RES_RECURSE | RES_DEFNAMES | RES_DNSRCH) _res.options |= RES_DEFAULT; #endif if (!(_res.options & RES_INIT)) if (res_init() == -1) return(-1); #ifdef DEBUG if (_res.options & RES_DEBUG) printf("cptres_search()\n"); #endif /* DEBUG */ errno = 0; for (cp = name, NumDots = 0; *cp; cp++) if (*cp == '.') NumDots++; if ((NumDots && cp[-1] == '.') || (_res.options & RES_DEFNAMES) == 0) { if (cp[-1] == '.') cp[-1] = 0; n = oneTry(name, (char *)NULL, class, type, answer, anslen); if (cp[-1] == 0) cp[-1] = '.'; return (n); } if (NumDots == 0 && (cp = myhostalias(name))) return (oneTry(cp, (char *)NULL, class, type, answer, anslen)); n = -1; #ifdef RES_DNSRCH /* Try all in the domain name search list if we're running a bind recent enough to support it. Otherwise just search the default domain. */ if (_res.options & RES_DNSRCH) for (domain = _res.dnsrch; *domain; domain++) { n = oneTry(name, *domain, class, type, answer, anslen); if (n <= 0) return(n); hp = (HEADER *) answer; if (hp->rcode != NXDOMAIN || ! hp->aa) return (n); } #else /* RES_DNSRCH */ n = oneTry(name, _res.defdname, class, type, answer, anslen); if (n <= 0) return(n); hp = (HEADER *) answer; if (hp->rcode != NXDOMAIN || ! hp->aa) return (n); #endif /* RES_DNSRCH */ if (NumDots == 0) return (n); return (oneTry(name, (char *)NULL, class, type, answer, anslen)); } #endif /* RESOLVER_ENV */