/* * Copyright (c) 1986 Regents of the University of California * All Rights Reserved * * Redistribution and use in source and binary forms are permitted * provided that this notice is preserved and that due credit is given * to the University of California at Berkeley. The name of the University * may not be used to endorse or promote products derived from this * software without specific prior written permission. This software * is provided ``as is'' without express or implied warranty. */ /* * 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. */ #if _MINIX #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #undef ERROR #else #include #include #include #include #include #include #include #include #include #include #endif 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 FILE *filePtr; struct state orig; extern struct state _res; static u8_t *cname = NULL; int getclass = C_IN; int gettype, getdeftype = T_A; int verbose = 0; int list = 0; int server_specified = 0; union querybuf; int main _ARGS(( int c, char *v[] )); static int parsetype _ARGS(( char *s )); static int parseclass _ARGS(( char *s )); static void hperror _ARGS(( int errno )); static void printanswer _ARGS(( struct hostent *hp )); static int ListHosts _ARGS(( char *namePtr, int queryType )); static int gethostinfo _ARGS(( char *name )); static int getdomaininfo _ARGS(( char *name, char *domain )); static int getinfo _ARGS(( char *name, char *domain, int type )); static int printinfo _ARGS(( union querybuf *answer, u8_t *eom, int filter, int isls )); static char *DecodeError _ARGS(( int result )); static u8_t *pr_rr _ARGS(( u8_t *cp, u8_t *msg, FILE *file, int filter )); static u8_t * pr_cdname _ARGS(( u8_t *cp, u8_t *msg, u8_t *name, int namelen )); static char *pr_class _ARGS(( int class )); static char *pr_type _ARGS(( int type )); static int tcpip_writeall _ARGS(( int fd, char *buf, unsigned siz )); int main(c, v) char **v; { char *domain; ipaddr_t addr; register struct hostent *hp; register char *s, *p; register inverse = 0; register waitmode = 0; u8_t *oldcname; int ncnames; int isaddr; res_init(); _res.retrans = 5; if (c < 2) { fprintf(stderr, "Usage: host [-w] [-v] [-r] [-d] [-V] [-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 -V to always use a virtual circuit\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--; } else if (strcmp (v[1], "-V") == 0) { _res.options |= RES_USEVC; v++; c--; } } if (c > 2) { s = v[2]; server_specified++; if ((p = strchr(s, ':')) != NULL) *p++ = 0; isaddr = inet_aton(s, &addr); if (p != NULL) p[-1] = ':'; if (!isaddr) { hp = gethostbyname(s); if (hp == NULL) { fprintf(stderr,"Error in looking up server name:\n"); hperror(h_errno); exit(1); } _res.nsaddr= *(ipaddr_t *)hp->h_addr; printf("Using domain server:\n"); printanswer(hp); } else { _res.nsaddr_list[0]= addr; _res.nsport_list[0]= htons(NAMESERVER_PORT); printf("Using domain server %s", inet_ntoa(_res.nsaddr)); if (p != NULL) { printf(" on port %d", atoi(p)); _res.nsport_list[0]= htons(atoi(p)); } printf(":\n"); } } domain = v[1]; if (strcmp (domain, ".") != 0 && inet_aton(domain, &addr)) { static char ipname[sizeof("255.255.255.255.in-addr.arpa.")]; sprintf(ipname, "%d.%d.%d.%d.in-addr.arpa.", ((unsigned char *) &addr)[3], ((unsigned char *) &addr)[2], ((unsigned char *) &addr)[1], ((unsigned char *) &addr)[0]); domain = ipname; getdeftype = T_PTR; } hp = NULL; h_errno = TRY_AGAIN; /* * we handle default domains ourselves, thank you */ _res.options &= ~RES_DEFNAMES; if (list) exit(ListHosts(domain, gettype ? gettype : getdeftype)); oldcname = NULL; ncnames = 5; while (hp == NULL && h_errno == TRY_AGAIN) { cname = NULL; if (oldcname == NULL) hp = (struct hostent *)gethostinfo(domain); else hp = (struct hostent *)gethostinfo((char *)oldcname); if (cname) { if (ncnames-- == 0) { printf("Too many cnames. Possible loop.\n"); exit(1); } oldcname = cname; hp = NULL; h_errno = TRY_AGAIN; continue; } if (!waitmode) break; } if (hp == NULL) { hperror(h_errno); exit(1); } exit(0); } static int parsetype(s) char *s; { if (strcmp(s,"a") == 0) return(1); if (strcmp(s,"ns") == 0) return(2); if (strcmp(s,"md") == 0) return(3); if (strcmp(s,"mf") == 0) return(4); if (strcmp(s,"cname") == 0) return(5); if (strcmp(s,"soa") == 0) return(6); if (strcmp(s,"mb") == 0) return(7); if (strcmp(s,"mg") == 0) return(8); if (strcmp(s,"mr") == 0) return(9); if (strcmp(s,"null") == 0) return(10); if (strcmp(s,"wks") == 0) return(11); if (strcmp(s,"ptr") == 0) return(12); if (strcmp(s,"hinfo") == 0) return(13); if (strcmp(s,"minfo") == 0) return(14); if (strcmp(s,"mx") == 0) return(15); if (strcmp(s,"txt") == 0) /* Roy */ return(T_TXT); /* Roy */ if (strcmp(s,"uinfo") == 0) return(100); if (strcmp(s,"uid") == 0) return(101); if (strcmp(s,"gid") == 0) return(102); if (strcmp(s,"unspec") == 0) return(103); if (strcmp(s,"any") == 0) return(255); if (strcmp(s,"*") == 0) return(255); if (atoi(s)) return(atoi(s)); fprintf(stderr, "Invalid query type: %s\n", s); exit(2); } static int parseclass(s) char *s; { if (strcmp(s,"in") == 0) return(C_IN); if (strcmp(s,"chaos") == 0) return(C_CHAOS); if (strcmp(s,"hs") == 0) return(C_HS); if (strcmp(s,"any") == 0) return(C_ANY); if (atoi(s)) return(atoi(s)); fprintf(stderr, "Invalid query class: %s\n", s); exit(2); } static void printanswer(hp) register struct hostent *hp; { register char **cp; register ipaddr_t **hptr; printf("Name: %s\n", hp->h_name); printf("Address:"); for (hptr = (ipaddr_t **)hp->h_addr_list; *hptr; hptr++) printf(" %s", inet_ntoa(*(ipaddr_t *)*hptr)); printf("\nAliases:"); for (cp = hp->h_aliases; cp && *cp && **cp; cp++) printf(" %s", *cp); printf("\n\n"); } static void hperror(errno) int errno; { switch(errno) { 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 what you requested.\n"); break; } } typedef union querybuf { dns_hdr_t qb1; u8_t qb2[PACKETSZ]; } querybuf_t; static u8_t hostbuf[BUFSIZ+1]; static int gethostinfo(name) char *name; { register char *cp, **domain; int n; int hp; int nDomain; 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 && (cp = __hostalias(name))) { if (verbose) printf("Aliased to \"%s\"\n", cp); _res.options |= RES_DEFNAMES; return (getdomaininfo(cp, (char *)NULL)); } #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 (verbose) printf("Trying null domain\n"); return (getdomaininfo(name, (char *)NULL)); } static int getdomaininfo(name, domain) char *name, *domain; { return getinfo(name, domain, gettype ? gettype : getdeftype); } static int getinfo(name, domain, type) char *name, *domain; { dns_hdr_t *hp; u8_t *eom, *bp, *cp; querybuf_t buf, answer; int n, n1, i, j, nmx, ancount, nscount, arcount, qdcount, buflen; u_short pref, class; char host[2*MAXDNAME+2]; 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, (char *)NULL, 0, NULL, (char *)&buf, sizeof(buf)); if (n < 0) { if (_res.options & RES_DEBUG) printf("res_mkquery failed\n"); h_errno = NO_RECOVERY; return(0); } n = res_send((char *)&buf, n, (char *)&answer, sizeof(answer)); if (n < 0) { if (_res.options & RES_DEBUG) printf("res_send failed\n"); h_errno = TRY_AGAIN; return (0); } eom = (u8_t *)&answer + n; return(printinfo(&answer, eom, T_ANY, 0)); } static int printinfo(answer, eom, filter, isls) querybuf_t *answer; u8_t *eom; int filter; int isls; { dns_hdr_t *hp; u8_t *bp, *cp; int n, n1, i, j, nmx, ancount, nscount, arcount, qdcount, buflen; u_short pref, class; /* * find first satisfactory answer */ hp = (dns_hdr_t *) answer; ancount = ntohs(hp->dh_ancount); qdcount = ntohs(hp->dh_qdcount); nscount = ntohs(hp->dh_nscount); arcount = ntohs(hp->dh_arcount); if (_res.options & RES_DEBUG || (verbose && isls == 0)) printf("rcode = %d (%s), ancount=%d\n", hp->dh_flag2 & DHF_RCODE, DecodeError(hp->dh_flag2 & DHF_RCODE), ancount); if (hp->dh_flag2 & DHF_RCODE != NOERROR || (ancount+nscount+arcount) == 0) { switch (hp->dh_flag2 & DHF_RCODE) { case NXDOMAIN: /* Check if it's an authoritive answer */ if (hp->dh_flag1 & DHF_AA) { h_errno = HOST_NOT_FOUND; return(0); } else { h_errno = TRY_AGAIN; 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 = (u8_t *)answer + sizeof(dns_hdr_t); if (qdcount) { cp += dn_skipname((u8_t *)cp,(u8_t *)eom) + QFIXEDSZ; while (--qdcount > 0) cp += dn_skipname((u8_t *)cp,(u8_t *)eom) + QFIXEDSZ; } if (ancount) { if (!(hp->dh_flag1 & DHF_AA)) if (verbose && isls == 0) printf("The following answer is not authoritative:\n"); while (--ancount >= 0 && cp && cp < eom) { cp = pr_rr(cp, (u8_t *)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 = pr_rr(cp, (u8_t *)answer, stdout, filter); } } if (arcount) { printf("Additional information:\n"); while (--arcount >= 0 && cp && cp < eom) { cp = pr_rr(cp, (u8_t *)answer, stdout, filter); } } return(1); } static u8_t cnamebuf[MAXDNAME]; /* * Print resource record fields in human readable form. */ static u8_t * pr_rr(cp, msg, file, filter) u8_t *cp, *msg; FILE *file; int filter; { int type, class, dlen, n, c, proto, ttl; ipaddr_t inaddr; u8_t *cp1; struct protoent *protop; struct servent *servp; char punc; int doprint; u8_t name[MAXDNAME]; if ((cp = pr_cdname(cp, msg, name, sizeof(name))) == NULL) return (NULL); /* compression error */ type = _getshort(cp); cp += sizeof(u_short); class = _getshort(cp); cp += sizeof(u_short); ttl = _getlong(cp); cp += sizeof(u_long); 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 += sizeof(u_short); cp1 = cp; /* * Print type specific data, if appropriate */ switch (type) { case T_A: switch (class) { case C_IN: bcopy((char *)cp, (char *)&inaddr, sizeof(inaddr)); 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)-1) >= 0) { strcat((char *) cnamebuf, "."); if (gettype != T_CNAME && gettype != T_ANY) 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 = pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file,"%c%s",punc, name); break; case T_HINFO: if (n = *cp++) { if (doprint) fprintf(file,"%c%.*s", punc, n, cp); cp += n; } if (n = *cp++) { if (doprint) fprintf(file,"%c%.*s", punc, n, cp); cp += n; } break; case T_SOA: cp = pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file,"\t%s", name); cp = 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 += sizeof(u_long); if (doprint) fprintf(file,"\n\t\t\t%ld\t;refresh period", _getlong(cp)); cp += sizeof(u_long); if (doprint) fprintf(file,"\n\t\t\t%ld\t;retry refresh this often", _getlong(cp)); cp += sizeof(u_long); if (doprint) fprintf(file,"\n\t\t\t%ld\t;expiration period", _getlong(cp)); cp += sizeof(u_long); if (doprint) fprintf(file,"\n\t\t\t%ld\t;minimum TTL\n\t\t\t)", _getlong(cp)); cp += sizeof(u_long); break; case T_MX: if (doprint) if (verbose) fprintf(file,"\t%d ",_getshort(cp)); else fprintf(file," (pri=%d) by ",_getshort(cp)); cp += sizeof(u_short); cp = pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file, "%s", name); break; case T_MINFO: cp = pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file,"%c%s",punc, name); cp = pr_cdname(cp, msg, name, sizeof(name)); if (doprint) fprintf(file," %s", name); break; /* Roy start */ case T_TXT: if (n = *cp++) { if (doprint) fprintf(file,"%c%.*s", punc, n, cp); cp += n; } break; /* Roy end */ 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 += sizeof(int); } break; case T_WKS: if (dlen < sizeof(u_long) + 1) break; bcopy((char *)cp, (char *)&inaddr, sizeof(inaddr)); cp += sizeof(u_long); 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 (cp); } static char nbuf[20]; /* * Return a string for the type */ static char * pr_type(type) int type; { switch (type) { case T_A: return(verbose? "A" : "has address"); case T_NS: /* authoritative server */ return("NS"); #ifdef OLDRR case T_MD: /* mail destination */ return("MD"); case T_MF: /* mail forwarder */ return("MF"); #endif /* OLDRR */ case T_CNAME: /* connonical name */ return(verbose? "CNAME" : "is a nickname for"); case T_SOA: /* start of authority zone */ return("SOA"); case T_MB: /* mailbox domain name */ return("MB"); case T_MG: /* mail group member */ return("MG"); case T_MX: /* mail routing info */ return(verbose? "MX" : "mail is handled"); /* Roy start */ case T_TXT: /* TXT - descriptive info */ return(verbose? "TXT" : "descriptive text"); /* Roy end */ case T_MR: /* mail rename name */ return("MR"); case T_NULL: /* null resource record */ return("NULL"); case T_WKS: /* well known service */ return("WKS"); case T_PTR: /* domain name pointer */ return("PTR"); case T_HINFO: /* host information */ return("HINFO"); case T_MINFO: /* mailbox information */ return("MINFO"); case T_AXFR: /* zone transfer */ return("AXFR"); case T_MAILB: /* mail box */ return("MAILB"); case T_MAILA: /* mail address */ return("MAILA"); case T_ANY: /* matches any type */ return("ANY"); case T_UINFO: return("UINFO"); case T_UID: return("UID"); case T_GID: return("GID"); default: return (sprintf(nbuf, "%d", type) == EOF ? NULL : nbuf); } } /* * Return a mnemonic for class */ static char * pr_class(class) int class; { switch (class) { case C_IN: /* internet class */ return(verbose? " IN" : ""); case C_CHAOS: /* chaos class */ return(verbose? " CHAOS" : ""); case C_HS: /* Hesiod class */ return(verbose? " HS" : ""); case C_ANY: /* matches any class */ return(" ANY"); default: return (sprintf(nbuf," %d", class) == EOF ? NULL : nbuf); } } static u8_t * pr_cdname(cp, msg, name, namelen) u8_t *cp, *msg; u8_t *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. * ****************************************************************************** */ static int ListHosts(namePtr, queryType) char *namePtr; int queryType; /* e.g. T_A */ { querybuf_t buf, answer; dns_hdr_t *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; u8_t *cp, *nmp; u8_t name[NAME_LEN]; char dname[2][NAME_LEN]; u8_t 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; char *tcp_serv_name; int tcp_fd; nwio_tcpconf_t tcpconf; nwio_tcpcl_t clopt; int terrno; /* * 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((char *)&_res.nsaddr, 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, (char *)0, 0, (struct rrec *)0, (char *)&buf, sizeof(buf)); if (msglen < 0) { printf("res_mkquery failed\n"); return (ERROR); } msglen = res_send((char *)&buf,msglen,(char *)&answer, 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.dh_flag2 & DHF_RCODE, DecodeError(answer.qb1.dh_flag2 & DHF_RCODE), ntohs(answer.qb1.dh_ancount)); /* * Analyze response to our NS lookup */ nscount = ntohs(answer.qb1.dh_ancount) + ntohs(answer.qb1.dh_nscount) + ntohs(answer.qb1.dh_arcount); if (answer.qb1.dh_flag2 & DHF_RCODE != NOERROR || nscount == 0) { switch (answer.qb1.dh_flag2 & DHF_RCODE) { case NXDOMAIN: /* Check if it's an authoritive answer */ if (answer.qb1.dh_flag1 & DHF_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 = answer.qb2 + sizeof(dns_hdr_t); if (ntohs(answer.qb1.dh_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 += sizeof(u_short) + sizeof(u_short) + sizeof(u_long); dlen = _getshort(cp); cp += sizeof(u_short); 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((char *)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, (char *)0, 0, (struct rrec *)0, (char *) &buf, sizeof(buf)); if (msglen < 0) { if (_res.options & RES_DEBUG) { fprintf(stderr, "ListHosts: Res_mkquery failed\n"); } return (ERROR); } /* * Set up a virtual circuit to the server. */ tcp_serv_name= getenv("TCP_DEVICE"); if (!tcp_serv_name) tcp_serv_name= TCP_DEVICE; for (;thisns < numnsaddr; thisns++) { tcp_fd= open(tcp_serv_name, O_RDWR); if (tcp_fd == -1) { fprintf(stderr, "unable to open '%s': %s\n", tcp_serv_name, strerror(errno)); return ERROR; } tcpconf.nwtc_flags= NWTC_EXCL | NWTC_LP_SEL | NWTC_SET_RA | NWTC_SET_RP; tcpconf.nwtc_remaddr= *(ipaddr_t *)nsipaddr[thisns]; tcpconf.nwtc_remport= _res.nsport_list[0]; result= ioctl(tcp_fd, NWIOSTCPCONF, &tcpconf); if (result == -1) { fprintf(stderr, "tcp_ioc_setconf failed: %s\n", strerror(errno)); close(tcp_fd); return ERROR; } if (_res.options & RES_DEBUG || verbose) printf("Trying %s\n", inet_ntoa(tcpconf.nwtc_remaddr)); clopt.nwtcl_flags= 0; result= ioctl(tcp_fd, NWIOTCPCONN, &clopt); if (result == 0) break; terrno= errno; if (verbose) fprintf(stderr, "Connection failed, trying next server: %s\n", strerror(errno)); close(tcp_fd); } if (thisns >= numnsaddr) { printf("No server for that domain responded\n"); if (!verbose) fprintf(stderr, "Error from the last server was: %s\n", strerror(terrno)); return(ERROR); } /* * Send length & message for zone transfer */ len = htons(msglen); result= tcpip_writeall(tcp_fd, (char *)&len, sizeof(len)); if (result != sizeof(len)) { fprintf(stderr, "write failed: %s\n", strerror(errno)); close(tcp_fd); return ERROR; } result= tcpip_writeall(tcp_fd, (char *)&buf, msglen); if (result != msglen) { fprintf(stderr, "write failed: %s\n", strerror(errno)); close(tcp_fd); return ERROR; } filePtr = stdout; while (1) { /* * Read the length of the response. */ cp = (u8_t *) &buf; amtToRead = sizeof(u_short); while(amtToRead > 0) { result = read(tcp_fd, (char *)cp, amtToRead); if (result <= 0) break; cp += result; amtToRead -= result; } if (amtToRead) { error = ERR_READING_LEN; break; } if ((len = htons(*(u_short *)&buf)) == 0) { break; /* nothing left to read */ } /* * Read the response. */ amtToRead = len; cp = (u8_t *) &buf; while(amtToRead > 0) { result = read(tcp_fd, (char *)cp, amtToRead); if (result<= 0) break; cp += result; amtToRead -= result; } if (amtToRead) { error = ERR_READING_MSG; break; } i = buf.qb1.dh_flag2 & DHF_RCODE; if (i != NOERROR || ntohs(buf.qb1.dh_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"); close(tcp_fd); 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 + sizeof(dns_hdr_t); if (ntohs(buf.qb1.dh_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)) { dn_expand(buf.qb2, buf.qb2 + len, nmp, (u8_t *)dname[soacnt], sizeof(dname[0])); if (soacnt) { if (strcmp(dname[0], dname[1]) == 0) break; } else soacnt++; } } close(tcp_fd); 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 = (dns_hdr_t *) &buf; fprintf(stderr,"ListHosts: error receiving zone transfer:\n"); fprintf(stderr, " result: %s, answers = %d, authority = %d, additional = %d\n", resultcodes[headerPtr->dh_flag2 & DHF_RCODE], ntohs(headerPtr->dh_ancount), ntohs(headerPtr->dh_nscount), ntohs(headerPtr->dh_arcount)); return(ERROR); default: return(ERROR); } } static 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; case NOCHANGE: return("No change"); break; 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"); } static int tcpip_writeall(fd, buf, siz) int fd; char *buf; unsigned siz; { unsigned siz_org; int nbytes; siz_org= siz; while (siz) { nbytes= write(fd, buf, siz); if (nbytes == -1) return nbytes; assert(siz >= nbytes); buf += nbytes; siz -= nbytes; } return siz_org; }