/* * ++Copyright++ 1986 * - * Copyright (c) 1986 * 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-- */ #ifndef lint char copyright[] = "@(#) Copyright (c) 1986 Regents of the University of California.\n\ portions Copyright (c) 1993 Digital Equipment Corporation\n\ All rights reserved.\n"; #endif /* not lint */ /* * Actually, this program is from Rutgers University, however it is * based on nslookup and other pieces of named tools, so it needs * that copyright notice. */ #ifndef lint static char rcsid[] = "$Id: host.c,v 8.12 1996/10/08 04:51:07 vixie Exp $"; #endif /* not lint */ #include #include #include #include #include #include #include #include #include #include #include "../conf/portability.h" extern int h_errno; #define NUMMX 50 #define SUCCESS 0 #define TIME_OUT -1 #define NO_INFO -2 #define ERROR -3 #define NONAUTH -4 #define NAME_LEN 256 #ifndef T_TXT #define T_TXT 16 #endif #ifndef NO_DATA #define NO_DATA NO_ADDRESS #endif #ifndef C_HS #define C_HS 4 #endif int sockFD; FILE *filePtr; char *DecodeError(); static struct __res_state orig; extern struct __res_state _res; static char *cname = NULL; int getclass = C_IN; int gettype; int verbose = 0; int list = 0; int server_specified = 0; u_char *pr_cdname(); char *pr_class(), *pr_rr(); const char *pr_type(); main(c, v) int c; char **v; { unsigned addr; register struct hostent *hp; register char *s; register inverse = 0; register waitmode = 0; char *oldcname; int ncnames; res_init(); _res.retrans = 5; if (c < 2) { fprintf(stderr, "Usage: host [-w] [-v] [-r] [-d] [-t querytype] [-c class] [-a] host [server]\n -w to wait forever until reply\n -v for verbose output\n -r to disable recursive processing\n -d to turn on debugging output\n -t querytype to look for a specific type of information\n -c class to look for non-Internet data\n -a is equivalent to '-v -t *'\n"); exit(1); } while (c > 2 && v[1][0] == '-') { if (strcmp (v[1], "-w") == 0) { _res.retry = 1; _res.retrans = 15; waitmode = 1; v++; c--; } else if (strcmp (v[1], "-r") == 0) { _res.options &= ~RES_RECURSE; v++; c--; } else if (strcmp (v[1], "-d") == 0) { _res.options |= RES_DEBUG; v++; c--; } else if (strcmp (v[1], "-v") == 0) { verbose = 1; v++; c--; } else if (strcmp (v[1], "-l") == 0) { list = 1; v++; c--; } else if (strncmp (v[1], "-t", 2) == 0) { v++; c--; gettype = parsetype(v[1]); v++; c--; } else if (strncmp (v[1], "-c", 2) == 0) { v++; c--; getclass = parseclass(v[1]); v++; c--; } else if (strcmp (v[1], "-a") == 0) { verbose = 1; gettype = T_ANY; v++; c--; } } if (c > 2) { s = v[2]; server_specified++; if (!inet_aton(s, (struct in_addr *)&addr)) { hp = gethostbyname(s); if (hp == NULL) { fprintf(stderr,"Error in looking up server name:\n"); hperror(h_errno); exit(1); } _res.nsaddr.sin_addr = *(struct in_addr *)hp->h_addr; printf("Using domain server:\n"); printanswer(hp); } else { _res.nsaddr.sin_family = AF_INET; _res.nsaddr.sin_addr.s_addr = addr; _res.nsaddr.sin_port = htons(NAMESERVER_PORT); printf("Using domain server %s:\n", inet_ntoa(_res.nsaddr.sin_addr)); } _res.nscount = 1; _res.retry = 2; } if (strcmp (v[1], ".") == 0 || !inet_aton(v[1], (struct in_addr *)&addr)) addr = -1; hp = NULL; h_errno = TRY_AGAIN; /* * we handle default domains ourselves, thank you */ _res.options &= ~RES_DEFNAMES; if (list) exit(ListHosts(v[1], gettype ? gettype : T_A)); oldcname = NULL; ncnames = 5; while (hp == NULL && h_errno == TRY_AGAIN) { if (addr == -1) { cname = NULL; if (oldcname == NULL) hp = (struct hostent *)gethostinfo(v[1]); else hp = (struct hostent *)gethostinfo(oldcname); if (cname) { if (ncnames-- == 0) { printf("Too many cnames. Possible loop.\n"); exit(1); } strcat(cname, "."); oldcname = cname; hp = NULL; h_errno = TRY_AGAIN; continue; } } else { hp = gethostbyaddr((char*)&addr, 4, AF_INET); if (hp) printanswer(hp); } if (!waitmode) break; } if (hp == NULL) { hperror(h_errno); exit(1); } exit(0); } int parsetype(s) char *s; { int type, success; type = sym_ston(__p_type_syms, s, &success); if (success) return type; if (strcmp(s,"*") == 0) return(T_ANY); if (atoi(s)) return(atoi(s)); fprintf(stderr, "Invalid query type: %s\n", s); exit(2); } int parseclass(s) char *s; { int class, success; class = sym_ston(__p_class_syms, s, &success); if (success) return class; if (atoi(s)) return(atoi(s)); fprintf(stderr, "Invalid query class: %s\n", s); exit(2); } printanswer(hp) register struct hostent *hp; { register char **cp; register long **hptr; printf("Name: %s\n", hp->h_name); printf("Address:"); for (hptr = (long **)hp->h_addr_list; *hptr; hptr++) printf(" %s", inet_ntoa(*(struct in_addr *)*hptr)); printf("\nAliases:"); for (cp = hp->h_aliases; cp && *cp && **cp; cp++) printf(" %s", *cp); printf("\n\n"); } hperror(errnum) int errnum; { switch(errnum) { case HOST_NOT_FOUND: fprintf(stderr,"Host not found.\n"); break; case TRY_AGAIN: fprintf(stderr,"Host not found, try again.\n"); break; case NO_RECOVERY: fprintf(stderr,"No recovery, Host not found.\n"); break; case NO_ADDRESS: fprintf(stderr,"There is an entry for this host, but it doesn't have "); switch (gettype) { case T_A: fprintf(stderr,"an Internet address.\n"); break; case T_NS: fprintf(stderr,"a Name Server.\n"); break; case T_MD: fprintf(stderr,"a Mail Destination.\n"); break; case T_MF: fprintf(stderr,"a Mail Forwarder.\n"); break; case T_CNAME: fprintf(stderr,"a Canonical Name.\n"); break; case T_SOA: fprintf(stderr,"a Start of Authority record.\n"); break; case T_MB: fprintf(stderr,"a Mailbox Domain Name.\n"); break; case T_MG: fprintf(stderr,"a Mail Group Member.\n"); break; case T_MR: fprintf(stderr,"a Mail Rename Name.\n"); break; case T_NULL: fprintf(stderr,"a Null Resource record.\n"); break; case T_WKS: fprintf(stderr,"any Well Known Service information.\n"); break; case T_PTR: fprintf(stderr,"a Pointer record.\n"); break; case T_HINFO: fprintf(stderr,"any Host Information.\n"); break; case T_MINFO: fprintf(stderr,"any Mailbox Information.\n"); break; case T_MX: fprintf(stderr,"a Mail Exchanger record.\n"); break; case T_TXT: fprintf(stderr,"a Text record.\n"); break; case T_RP: fprintf(stderr,"a Responsible Person.\n"); break; case T_UINFO: fprintf(stderr,"any User Information.\n"); break; case T_UID: fprintf(stderr,"a User ID.\n"); break; case T_GID: fprintf(stderr,"a Group ID.\n"); break; case T_SRV: fprintf(stderr,"a Server Selector.\n"); break; case T_NAPTR: fprintf(stderr,"a URN Naming Authority.\n"); break; case T_UNSPEC: fprintf(stderr,"any Unspecified Format data.\n"); break; default: fprintf(stderr,"the information you requested.\n"); break; } break; } } typedef union { HEADER qb1; u_char qb2[PACKETSZ]; } querybuf; static u_char hostbuf[BUFSIZ+1]; gethostinfo(name) char *name; { char *cp, **domain; const char *tp; u_int n; int hp; int nDomain; int asis = 0; if (strcmp(name, ".") == 0) return(getdomaininfo(name, NULL)); for (cp = name, n = 0; *cp; cp++) if (*cp == '.') n++; if (n && cp[-1] == '.') { if (cp[-1] == '.') cp[-1] = 0; hp = getdomaininfo(name, (char *)NULL); if (cp[-1] == 0) cp[-1] = '.'; return (hp); } if (n == 0 && (tp = hostalias(name))) { if (verbose) printf("Aliased to \"%s\"\n", tp); _res.options |= RES_DEFNAMES; return (getdomaininfo(tp, (char *)NULL)); } if (n >= _res.ndots) { asis = 1; if (verbose) printf("Trying null domain\n"); if(hp = getdomaininfo(name, (char*)NULL)) return(hp); } #ifdef MAXDS for (nDomain = 0; _res.defdname_list[nDomain][0] != 0; nDomain++) { for (domain = _res.dnsrch_list[nDomain]; *domain; domain++) { if (verbose) printf("Trying domain \"%s\"\n", *domain); hp = getdomaininfo(name, *domain); if (hp) return (hp); } } #else for (domain = _res.dnsrch; *domain; domain++) { if (verbose) printf("Trying domain \"%s\"\n", *domain); hp = getdomaininfo(name, *domain); if (hp) return (hp); } #endif if (h_errno != HOST_NOT_FOUND || (_res.options & RES_DNSRCH) == 0) return (0); if (!asis) return (0); if (verbose) printf("Trying null domain\n"); return (getdomaininfo(name, (char *)NULL)); } getdomaininfo(name, domain) char *name, *domain; { int val1, val2; if (gettype) return getinfo(name, domain, gettype); else { val1 = getinfo(name, domain, T_A); if (cname || verbose) return val1; val2 = getinfo(name, domain, T_MX); return val1 || val2; } } getinfo(name, domain, type) char *name, *domain; int type; { HEADER *hp; char *eom, *bp, *cp; querybuf buf, answer; int n, n1, i, j, nmx, ancount, nscount, arcount, qdcount, buflen; u_short pref, class; char host[MAXDNAME]; if (domain == NULL) (void)sprintf(host, "%.*s", MAXDNAME, name); else (void)sprintf(host, "%.*s.%.*s", MAXDNAME, name, MAXDNAME, domain); n = res_mkquery(QUERY, host, getclass, type, NULL, 0, NULL, buf.qb2, sizeof(buf)); if (n < 0) { if (_res.options & RES_DEBUG) printf("res_mkquery failed\n"); h_errno = NO_RECOVERY; return(0); } n = res_send(buf.qb2, n, answer.qb2, sizeof answer); if (n < 0) { if (_res.options & RES_DEBUG) printf("res_send failed\n"); h_errno = TRY_AGAIN; return (0); } eom = (char *)&answer + n; return(printinfo(&answer, eom, T_ANY, 0)); } printinfo(answer, eom, filter, isls) querybuf *answer; u_char *eom; int filter; int isls; { HEADER *hp; u_char *bp, *cp; int n, n1, i, j, nmx, ancount, nscount, arcount, qdcount, buflen; u_short pref, class; /* * find first satisfactory answer */ hp = (HEADER *) answer; ancount = ntohs(hp->ancount); qdcount = ntohs(hp->qdcount); nscount = ntohs(hp->nscount); arcount = ntohs(hp->arcount); if (_res.options & RES_DEBUG || (verbose && isls == 0)) printf("rcode = %d (%s), ancount=%d\n", hp->rcode, DecodeError(hp->rcode), ancount); if (hp->rcode != NOERROR || (ancount+nscount+arcount) == 0) { switch (hp->rcode) { case NXDOMAIN: h_errno = HOST_NOT_FOUND; return(0); case SERVFAIL: h_errno = TRY_AGAIN; return(0); #ifdef OLDJEEVES /* * Jeeves (TOPS-20 server) still does not * support MX records. For the time being, * we must accept FORMERRs as the same as * NOERROR. */ case FORMERR: #endif /*OLDJEEVES*/ case NOERROR: /* TpB - set a return error for this case. NO_DATA */ h_errno = NO_DATA; return(0); /* was 1,but now indicates exception */ #ifndef OLDJEEVES case FORMERR: #endif /*OLDJEEVES*/ case NOTIMP: case REFUSED: h_errno = NO_RECOVERY; return(0); } return (0); } bp = hostbuf; nmx = 0; buflen = sizeof(hostbuf); cp = (u_char *)answer + HFIXEDSZ; if (qdcount) { cp += dn_skipname(cp, eom) + QFIXEDSZ; while (--qdcount > 0) cp += dn_skipname(cp, eom) + QFIXEDSZ; } if (ancount) { if (!hp->aa) if (verbose && isls == 0) printf("The following answer is not authoritative:\n"); while (--ancount >= 0 && cp && cp < eom) { cp = (u_char *)pr_rr(cp, answer, stdout, filter); /* * When we ask for address and there is a CNAME, it seems to return * both the CNAME and the address. Since we trace down the CNAME * chain ourselves, we don't really want to print the address at * this point. */ if (cname && ! verbose) return (1); } } if (! verbose) return (1); if (nscount) { printf("For authoritative answers, see:\n"); while (--nscount >= 0 && cp && cp < eom) { cp = (u_char *)pr_rr(cp, answer, stdout, filter); } } if (arcount) { printf("Additional information:\n"); while (--arcount >= 0 && cp && cp < eom) { cp = (u_char *)pr_rr(cp, answer, stdout, filter); } } return(1); } static char cnamebuf[MAXDNAME]; /* * Print resource record fields in human readable form. */ char * pr_rr(cp, msg, file, filter) u_char *cp, *msg; FILE *file; int filter; { int type, class, dlen, n, c, proto, ttl; struct in_addr inaddr; u_char *cp1; struct protoent *protop; struct servent *servp; char punc; int doprint; char name[MAXDNAME]; if ((cp = (u_char *)pr_cdname(cp, msg, name, sizeof(name))) == NULL) return (NULL); /* compression error */ type = _getshort(cp); cp += INT16SZ; class = _getshort(cp); cp += INT16SZ; ttl = _getlong(cp); cp += INT32SZ; if (filter == type || filter == T_ANY || (filter == T_A && (type == T_PTR || type == T_NS))) doprint = 1; else doprint = 0; if (doprint) if (verbose) fprintf(file,"%s\t%d%s\t%s", name, ttl, pr_class(class), pr_type(type)); else fprintf(file,"%s%s %s",name, pr_class(class), pr_type(type)); if (verbose) punc = '\t'; else punc = ' '; dlen = _getshort(cp); cp += INT16SZ; cp1 = cp; /* * Print type specific data, if appropriate */ switch (type) { case T_A: switch (class) { case C_IN: bcopy(cp, (char *)&inaddr, INADDRSZ); if (dlen == 4) { if (doprint) fprintf(file,"%c%s", punc, inet_ntoa(inaddr)); cp += dlen; } else if (dlen == 7) { if (doprint) { fprintf(file,"%c%s", punc, inet_ntoa(inaddr)); fprintf(file,", protocol = %d", cp[4]); fprintf(file,", port = %d", (cp[5] << 8) + cp[6]); } cp += dlen; } break; } break; case T_CNAME: if (dn_expand(msg, msg + 512, cp, cnamebuf, sizeof(cnamebuf)) >= 0) cname = cnamebuf; case T_MB: #ifdef OLDRR case T_MD: case T_MF: #endif /* OLDRR */ case T_MG: case T_MR: case T_NS: case T_PTR: cp = (u_char *)pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file,"%c%s",punc, name); break; case T_HINFO: case T_ISDN: { u_char *cp2 = cp + dlen; if (n = *cp++) { if (doprint) fprintf(file,"%c%.*s", punc, n, cp); cp += n; } if ((cp < cp2) && (n = *cp++)) { if (doprint) fprintf(file,"%c%.*s", punc, n, cp); cp += n; } else if (type == T_HINFO) if (doprint) fprintf(file,"\n; *** Warning *** OS-type missing"); } break; case T_SOA: cp = (u_char *)pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file,"\t%s", name); cp = (u_char *)pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file," %s", name); if (doprint) fprintf(file,"(\n\t\t\t%ld\t;serial (version)", _getlong(cp)); cp += INT32SZ; if (doprint) fprintf(file,"\n\t\t\t%ld\t;refresh period", _getlong(cp)); cp += INT32SZ; if (doprint) fprintf(file,"\n\t\t\t%ld\t;retry refresh this often", _getlong(cp)); cp += INT32SZ; if (doprint) fprintf(file,"\n\t\t\t%ld\t;expiration period", _getlong(cp)); cp += INT32SZ; if (doprint) fprintf(file,"\n\t\t\t%ld\t;minimum TTL\n\t\t\t)", _getlong(cp)); cp += INT32SZ; break; case T_MX: case T_AFSDB: case T_RT: if (doprint) if (type == T_MX && !verbose) fprintf(file," (pri=%d) by ", _getshort(cp)); else if (verbose) fprintf(file,"\t%d ", _getshort(cp)); else fprintf(file," "); cp += sizeof(u_short); cp = (u_char *)pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file, "%s", name); break; case T_SRV: /* priority */ if (doprint) fprintf(file," %d", _getshort(cp)); cp += sizeof(u_short); /* weight */ if (doprint) fprintf(file," %d", _getshort(cp)); cp += sizeof(u_short); /* port */ if (doprint) fprintf(file," %d", _getshort(cp)); cp += sizeof(u_short); /* target */ cp = (u_char *)pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file,"%s",name); break; case T_NAPTR: /* order */ if (doprint) fprintf(file," %d", _getshort(cp)); cp += sizeof(u_short); /* preference */ if (doprint) fprintf(file," %d", _getshort(cp)); cp += sizeof(u_short); /* Flags */ n = *cp++; if (doprint) if(n) fprintf(file,"%c%.*s", punc, n, cp); else fprintf(file,"%c\"\"",punc); cp += n; /* Service */ n = *cp++; if (doprint) if(n) fprintf(file,"%c%.*s", punc, n, cp); else fprintf(file,"%c\"\"",punc); cp += n; /* Regexp */ n = *cp++; if (doprint) if(n) fprintf(file,"%c%.*s", punc, n, cp); else fprintf(file,"%c\"\"",punc); cp += n; /* replacement */ cp = (u_char *)pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file,"%s",name); break; case T_MINFO: case T_RP: cp = (u_char *)pr_cdname(cp, msg, name, sizeof(name)); if (doprint){ if (type == T_RP) { char * p; if (p = strchr(name, '.')) *p = '@'; } fprintf(file, "%c%s", punc, name); } cp = (u_char *)pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file, " %s", name); break; case T_X25: if (n = *cp++) { if (doprint) fprintf(file,"%c%.*s", punc, n, cp); cp += n; } break; case T_TXT: { int n,j; u_char * end = cp + dlen; while (cp < end) { if (doprint) (void) fputs(" \"", file); if (n = *cp++) for (j = n; j > 0 && cp < end ; j --) { if (doprint) { if ((*cp == '\n') || (*cp == '"') || (*cp == '\\')) (void) putc('\\', file); (void) putc(*cp, file); } cp++; } if (doprint) (void) putc('"', file); } } break; case T_UINFO: if (doprint) fprintf(file,"%c%s", punc, cp); cp += dlen; break; case T_UID: case T_GID: if (dlen == 4) { if (doprint) fprintf(file,"%c%ld", punc, _getlong(cp)); cp += INT32SZ; } break; case T_WKS: if (dlen < INT32SZ + 1) break; bcopy(cp, (char *)&inaddr, INADDRSZ); cp += INT32SZ; proto = *cp++; protop = getprotobynumber(proto); if (doprint) if (protop) fprintf(file,"%c%s %s", punc, inet_ntoa(inaddr), protop->p_name); else fprintf(file,"%c%s %d", punc, inet_ntoa(inaddr), proto); n = 0; while (cp < cp1 + dlen) { c = *cp++; do { if (c & 0200) { servp = NULL; if (protop) servp = getservbyport (htons(n), protop->p_name); if (doprint) if (servp) fprintf(file, " %s", servp->s_name); else fprintf(file, " %d", n); } c <<= 1; } while (++n & 07); } break; default: if (doprint) fprintf(file,"%c???", punc); cp += dlen; } if (cp != cp1 + dlen) fprintf(file,"packet size error (%#x != %#x)\n", cp, cp1+dlen); if (doprint) fprintf(file,"\n"); return (char *)cp; } /* * Return a string for the type. A few get special treatment when * not in verbose mode, to make the program more chatty and easier to * understand. */ const char * pr_type(type) int type; { if (!verbose) switch (type) { case T_A: return("has address"); case T_CNAME: /* connonical name */ return("is a nickname for"); case T_MX: /* mail routing info */ return("mail is handled"); case T_TXT: /* TXT - descriptive info */ return("descriptive text"); case T_AFSDB: /* AFS/DCE info */ return("DCE or AFS service from"); } if (verbose) return (sym_ntos(__p_type_syms, type, NULL)); else return (sym_ntop(__p_type_syms, type, NULL)); } /* * Return a mnemonic for class */ char * pr_class(class) int class; { static char spacestr[20]; if (!verbose) switch (class) { case C_IN: /* internet class */ return ""; case C_HS: /* internet class FIXME? */ return ""; } spacestr[0] = ' '; strcpy (&spacestr[1], p_class (class)); return spacestr; } u_char * pr_cdname(cp, msg, name, namelen) u_char *cp, *msg; char *name; int namelen; { int n; if ((n = dn_expand(msg, msg + 512, cp, name, namelen - 2)) < 0) return (NULL); if (name[0] == '\0') { name[0] = '.'; name[1] = '\0'; } return (cp + n); } char *resultcodes[] = { "NOERROR", "FORMERR", "SERVFAIL", "NXDOMAIN", "NOTIMP", "REFUSED", "6", "7", "8", "9", "10", "11", "12", "13", "14", "NOCHANGE", }; /* ****************************************************************************** * * ListHosts -- * * Requests the name server to do a zone transfer so we * find out what hosts it knows about. * * Results: * SUCCESS the listing was successful. * ERROR the server could not be contacted because * a socket could not be obtained or an error * occured while receiving, or the output file * could not be opened. * ****************************************************************************** */ int ListHosts(namePtr, queryType) char *namePtr; int queryType; /* e.g. T_A */ { querybuf buf, answer; struct sockaddr_in sin; HEADER *headerPtr; int msglen; int amtToRead; int numRead; int i; int numAnswers = 0; int result; int soacnt = 0; u_short len; int dlen; int type; int nscount; u_char *cp, *nmp; char name[NAME_LEN]; char dname[2][NAME_LEN]; char domain[NAME_LEN]; /* names and addresses of name servers to try */ #define NUMNS 8 char nsname[NUMNS][NAME_LEN]; int nshaveaddr[NUMNS]; #define IPADDRSIZE 4 #define NUMNSADDR 16 char nsipaddr[NUMNSADDR][IPADDRSIZE]; int numns; int numnsaddr; int thisns; struct hostent *hp; enum { NO_ERRORS, ERR_READING_LEN, ERR_READING_MSG, ERR_PRINTING } error = NO_ERRORS; /* * normalize to not have trailing dot. We do string compares below * of info from name server, and it won't have trailing dots. */ i = strlen(namePtr); if (namePtr[i-1] == '.') namePtr[i-1] = 0; if (server_specified) { bcopy(&_res.nsaddr.sin_addr, nsipaddr[0], IPADDRSIZE); numnsaddr = 1; } else { /* * First we have to find out where to look. This needs a NS query, * possibly followed by looking up addresses for some of the names. */ msglen = res_mkquery(QUERY, namePtr, C_IN, T_NS, NULL, 0, NULL, buf.qb2, sizeof buf); if (msglen < 0) { printf("res_mkquery failed\n"); return (ERROR); } msglen = res_send(buf.qb2, msglen, answer.qb2, sizeof answer); if (msglen < 0) { printf("Unable to get to nameserver -- try again later\n"); return (ERROR); } if (_res.options & RES_DEBUG || verbose) printf("rcode = %d (%s), ancount=%d\n", answer.qb1.rcode, DecodeError(answer.qb1.rcode), ntohs(answer.qb1.ancount)); /* * Analyze response to our NS lookup */ nscount = ntohs(answer.qb1.ancount) + ntohs(answer.qb1.nscount) + ntohs(answer.qb1.arcount); if (answer.qb1.rcode != NOERROR || nscount == 0) { switch (answer.qb1.rcode) { case NXDOMAIN: /* Check if it's an authoritive answer */ if (answer.qb1.aa) { printf("No such domain\n"); } else { printf("Unable to get information about domain -- try again later.\n"); } break; case SERVFAIL: printf("Unable to get information about that domain -- try again later.\n"); break; case NOERROR: printf("That domain exists, but seems to be a leaf node.\n"); break; case FORMERR: case NOTIMP: case REFUSED: printf("Unrecoverable error looking up domain name.\n"); break; } return (0); } cp = (u_char *)answer.qb2 + HFIXEDSZ; if (ntohs(answer.qb1.qdcount) > 0) cp += dn_skipname(cp, answer.qb2 + msglen) + QFIXEDSZ; numns = 0; numnsaddr = 0; /* * Look at response from NS lookup for NS and A records. */ for (;nscount; nscount--) { cp += dn_expand(answer.qb2, answer.qb2 + msglen, cp, domain, sizeof(domain)); type = _getshort(cp); cp += INT16SZ + INT16SZ + INT32SZ; dlen = _getshort(cp); cp += INT16SZ; if (type == T_NS) { if (dn_expand(answer.qb2, answer.qb2 + msglen, cp, name, sizeof(name)) >= 0) { if (numns < NUMNS && strcasecmp((char *)domain, namePtr) == 0) { for (i = 0; i < numns; i++) if (strcasecmp(nsname[i], (char *)name) == 0) break; /* duplicate */ if (i >= numns) { strncpy(nsname[numns], (char *)name, sizeof(name)); nshaveaddr[numns] = 0; numns++; } } } } else if (type == T_A) { if (numnsaddr < NUMNSADDR) for (i = 0; i < numns; i++) { if (strcasecmp(nsname[i], (char *)domain) == 0) { nshaveaddr[i]++; bcopy(cp, nsipaddr[numnsaddr],IPADDRSIZE); numnsaddr++; break; } } } cp += dlen; } /* * Usually we'll get addresses for all the servers in the additional * info section. But in case we don't, look up their addresses. */ for (i = 0; i < numns; i++) { if (! nshaveaddr[i]) { register long **hptr; int numaddrs = 0; hp = gethostbyname(nsname[i]); if (hp) { for (hptr = (long **)hp->h_addr_list; *hptr; hptr++) if (numnsaddr < NUMNSADDR) { bcopy((char *)*hptr, nsipaddr[numnsaddr],IPADDRSIZE); numnsaddr++; numaddrs++; } } if (_res.options & RES_DEBUG || verbose) printf("Found %d addresses for %s by extra query\n", numaddrs, nsname[i]); } else if (_res.options & RES_DEBUG || verbose) printf("Found %d addresses for %s\n", nshaveaddr[i], nsname[i]); } } /* * Now nsipaddr has numnsaddr addresses for name servers that * serve the requested domain. Now try to find one that will * accept a zone transfer. */ thisns = 0; again: numAnswers = 0; soacnt = 0; /* * Create a query packet for the requested domain name. * */ msglen = res_mkquery(QUERY, namePtr, getclass, T_AXFR, NULL, 0, NULL, buf.qb2, sizeof buf); if (msglen < 0) { if (_res.options & RES_DEBUG) { fprintf(stderr, "ListHosts: Res_mkquery failed\n"); } return (ERROR); } bzero((char *)&sin, sizeof(sin)); sin.sin_family = AF_INET; sin.sin_port = htons(NAMESERVER_PORT); /* * Set up a virtual circuit to the server. */ for (;thisns < numnsaddr; thisns++) { if ((sockFD = socket(AF_INET, SOCK_STREAM, 0)) < 0) { perror("ListHosts"); return(ERROR); } bcopy(nsipaddr[thisns], &sin.sin_addr, IPADDRSIZE); if (_res.options & RES_DEBUG || verbose) printf("Trying %s\n", inet_ntoa(sin.sin_addr)); if (connect(sockFD, (struct sockaddr *)&sin, sizeof(sin)) >= 0) break; if (verbose) perror("Connection failed, trying next server"); (void) close(sockFD); sockFD = -1; } if (thisns >= numnsaddr) { printf("No server for that domain responded\n"); if (!verbose) perror("Error from the last server was"); return (ERROR); } /* * Send length & message for zone transfer */ __putshort(msglen, (u_char *)&len); if (write(sockFD, (char *)&len, INT16SZ) != INT16SZ || write(sockFD, (char *) &buf, msglen) != msglen) { perror("ListHosts"); (void) close(sockFD); sockFD = -1; return (ERROR); } filePtr = stdout; while (1) { /* * Read the length of the response. */ cp = (u_char *) &buf; amtToRead = INT16SZ; while(amtToRead > 0 && (numRead = read(sockFD, cp, amtToRead)) > 0){ cp += numRead; amtToRead -= numRead; } if (numRead <= 0) { error = ERR_READING_LEN; break; } if ((len = _getshort((u_char*)&buf)) == 0) { break; /* nothing left to read */ } /* * Read the response. */ amtToRead = len; cp = (u_char *) &buf; while(amtToRead > 0 && (numRead = read(sockFD, cp, amtToRead)) > 0){ cp += numRead; amtToRead -= numRead; } if (numRead <= 0) { error = ERR_READING_MSG; break; } i = buf.qb1.rcode; if (i != NOERROR || ntohs(buf.qb1.ancount) == 0) { if ((thisns+1) < numnsaddr && (i == SERVFAIL || i == NOTIMP || i == REFUSED)) { if (_res.options & RES_DEBUG || verbose) printf("Server failed, trying next server: %s\n", i != NOERROR ? DecodeError(i) : "Premature end of data"); (void) close(sockFD); sockFD = -1; thisns++; goto again; } printf("Server failed: %s\n", i != NOERROR ? DecodeError(i) : "Premature end of data"); break; } result = printinfo(&buf, cp, queryType, 1); if (! result) { error = ERR_PRINTING; break; } numAnswers++; cp = buf.qb2 + HFIXEDSZ; if (ntohs(buf.qb1.qdcount) > 0) cp += dn_skipname(cp, buf.qb2 + len) + QFIXEDSZ; nmp = cp; cp += dn_skipname(cp, (u_char *)&buf + len); if ((_getshort(cp) == T_SOA)) { (void) dn_expand(buf.qb2, buf.qb2 + len, nmp, dname[soacnt], sizeof dname[0]); if (soacnt) { if (strcmp((char *)dname[0], (char *)dname[1]) == 0) break; } else soacnt++; } } (void) close(sockFD); sockFD = -1; switch (error) { case NO_ERRORS: return (SUCCESS); case ERR_READING_LEN: return(ERROR); case ERR_PRINTING: fprintf(stderr,"*** Error during listing of %s: %s\n", namePtr, DecodeError(result)); return(result); case ERR_READING_MSG: headerPtr = (HEADER *) &buf; fprintf(stderr,"ListHosts: error receiving zone transfer:\n"); fprintf(stderr, " result: %s, answers = %d, authority = %d, additional = %d\n", resultcodes[headerPtr->rcode], ntohs(headerPtr->ancount), ntohs(headerPtr->nscount), ntohs(headerPtr->arcount)); return(ERROR); default: return(ERROR); } } char * DecodeError(result) int result; { switch(result) { case NOERROR: return("Success"); break; case FORMERR: return("Format error"); break; case SERVFAIL: return("Server failed"); break; case NXDOMAIN: return("Non-existent domain"); break; case NOTIMP: return("Not implemented"); break; case REFUSED: return("Query refused"); break; #ifdef NOCHANGE case NOCHANGE: return("No change"); break; #endif case NO_INFO: return("No information"); break; case ERROR: return("Unspecified error"); break; case TIME_OUT: return("Timed out"); break; case NONAUTH: return("Non-authoritative answer"); break; default: break; } return("BAD ERROR VALUE"); }