/* Copyright (c) 2002 Sam Trenholme * * TERMS * * 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. * * This software is provided 'as is' with no guarantees of correctness or * fitness for purpose. */ /* This is a version of getzone which does not convert the raw data in to MaraDNS' "csv1" zone file format; instead, it shows us the raw DNS packets on standard out. Designed to be used to make input for test_zoneserver.c */ /* Language-specific labels */ #include "../tuzona/getzone_locale.h" /* Other includes */ #include #include #include #include #include #include #include #include #include #include #include #include "../MaraDns.h" /* Function prototypes */ #include "../dns/functions_dns.h" #include "../libs/MaraHash.h" #include "../parse/functions_parse.h" extern int decomp_init(); void harderror(char *why) { printf("%s%s%s%s",LF,L_FATAL_COMMENT,why,LF); /* "\n", "# Fatal error: ", why, "\n" */ exit(3); } void timeout() { harderror(L_TIMEOUT); /* "Connection timed out" */ } /* OK, get a load of this. There are many older versions of BIND out there that completely, I mean, completely ignore the RFCs. Instead of sending a compressed DNS packet, it sends a single resource record which it considers a "DNS packet". The only way to search for this is to see if the first part of the message is a DNS packet. Since this behavior is not RFC complient, the "is this a buggy bind 8 packet" seacher will only allow /[A-Z][a-z][0-9]\-\_/ (perl5 regex) in a DNS name (we include _ because too many Microsoft shops have _ in their computer names) Input: A potential BIND-buggy DNS packet Output: 0 if it looks RFC complient, 1 if it's a !@#$ BIND4/8 packet, and -1 (JS_ERROR) if the sky fell down (actually, we just assume that it is a normal DNS packet with data which happens to look like a demented dlabel packet) */ int bind_bug_check(js_string *packet) { int place, len; place = 0; len = *packet->string; if(len <= 0 || len >= 64) return 0; /* This doesn't mean it's kosher; just that it is not the kind of trash Bind 8 spews */ while(len > 0 && len < 64) { while(len > 0) { unsigned char fina; /* Yes, I am pathetic enough to name variables after whatever beautiful latina has last caught my fancy */ len--; place++; if(place > packet->unit_count || place > packet->max_count) return 1; /* Again, doesn't mean it's kosher */ /* The /[A-Z][a-z][0-9]\-_/ regex; I'm doing this by sorting the regex in ASCII order and stopping if something is in a "hole" outside the regex 'cause I am too tired right now to do a big and/or expression */ fina = *(packet->string + place); if(fina < '-') /* The first ASCII character in this regex */ return 1; if(fina > '-' && fina < '0') return 1; if(fina > '9' && fina < 'A') return 1; if(fina > 'Z' && fina < '_') return 1; if(fina > '_' && fina < 'a') return 1; if(fina > 'z') /* UTF-8 in domain names would probably be a reasonable option if BIND was not the dominant DNS server out there */ return 1; /* End of regex */ } len = *(packet->string + place); } if(len == 0) return 0; return 1; } /* Usage: getzone */ int main(int argc, char **argv) { int sock, preference; int len_inet, length, place = 0, result; int soa_count = 0; struct sockaddr_in zone_server; /* AF_INET */ js_string *send, *zone, *get, *expand, *mxexpand; /* ( Sending and getting data from the client ) */ q_header header; q_rr rr; rr_soa soa; int qclass = 1; unsigned char len[2]; if((argc < 3 && argc > 4) || argv[1] == 0 || argv[2] == 0) { harderror(L_USAGE); /* "Usage: getzone zone_name zone_server_IP" */ } if(argc == 4 && argv[3] == 0) { harderror(L_USAGE); /* "Usage: getzone zone_name zone_server_IP" */ } /* Set up an option to change the query class */ if(argc == 4 && atoi(argv[3]) == 255) qclass = 255; /* Create a timeout alarm */ signal(SIGALRM,timeout); alarm(300); /* 5 minutes */ /* Create a socket to the zone server */ memset(&zone_server,0,sizeof zone_server); zone_server.sin_family = AF_INET; zone_server.sin_port = htons(53); zone_server.sin_addr.s_addr = inet_addr(argv[2]); if(zone_server.sin_addr.s_addr == INADDR_NONE) harderror(L_VALID_IP); /* "Please use a valid IP for the zone server" */ len_inet = sizeof zone_server; /* Create a TCP/IP socket */ sock = socket(PF_INET,SOCK_STREAM,0); if(sock == -1) harderror(L_NO_SOCK); /* "Unable to create TCP socket" */ /* Connect to the zone server */ if(connect(sock,(struct sockaddr *)&zone_server,len_inet) == -1) harderror(L_NO_CONNECT); /* "Unable to connect to zone server" */ /* OK, create a query to send over the connection */ if((send = js_create(256,1)) == 0) harderror(L_NO_SEND); /* "Unable to create send string object" */ /* The 12-byte header to send to the DNS server */ header.id = 45; header.qr = 0; header.opcode = 0; header.aa = 0; header.tc = 0; header.rd = 0; header.ra = 0; header.z = 0; header.rcode = 0; header.qdcount = 1; header.ancount = 0; header.nscount = 0; header.arcount = 0; if(make_hdr(&header,send) == JS_ERROR) harderror(L_NO_HEADER); /* "Unable to make DNS header" */ if((zone = js_create(128,1)) == 0) harderror(L_NO_ZSTRING); /* "Unable to create zone string object" */ if(js_qstr2js(zone,"A") == JS_ERROR) harderror(L_QSTR2JS_ERROR); /* "qstr2js" */ if(js_qappend(argv[1],zone) == JS_ERROR) harderror(L_APPEND_Z); /* "Unable to append zone string to zone object" */ /* Append trailing dot, if needed */ if(*(zone->string + zone->unit_count - 1) != '.') if(js_qappend(".",zone) == JS_ERROR) harderror(L_APPEND_D); /* "Unable to append dot at end of zone string object" */ /* Convert zone in to raw "over-the-wire" UDP data */ if(hname_2rfc1035(zone) == JS_ERROR) harderror(L_INVALID_NAME); /* "Invalid form of zone name" */ /* Append raw binary zone to data to send to server */ if(js_append(zone,send) == JS_ERROR) harderror(L_APPEND_ZS); /* "Can not append zone string to send string" */ /* Append query type and query class to data */ if(js_adduint16(send,252) == JS_ERROR) harderror(L_ADD_QT); /* "Could not add query type to send" */ if(js_adduint16(send,qclass) == JS_ERROR) harderror(L_ADD_QC); /* "Could not add query class to send" */ /* Question formed, now send question to server */ len[0] = (send->unit_count & 0xff00) >> 8; len[1] = send->unit_count & 0xff; if(write(sock,len,2) == -1) harderror(L_SEND_2BYTE); /* "Could not send 2-byte length header to zone server" */ if(write(sock,send->string,send->unit_count) == -1) harderror(L_SEND_QUERY); /* "Could not send query to zone server" */ if((rr.name = js_create(257,1)) == 0) harderror(L_C_RRNAME); /* "Could not create rr.name" */ if((soa.mname = js_create(257,1)) == 0) harderror(L_MNAME); /* "Could not create soa.mname" */ if((soa.rname = js_create(257,1)) == 0) harderror(L_RNAME); /* "Could not create soa.rname" */ while(recv(sock,len,2,MSG_WAITALL) == 2) { int is_buggy_bind_packet = 0; /* Get the length of the reply from the server */ length = ((len[0] << 8) & 0xff00) | (len[1] & 0xff); if(length < 12) harderror(L_NOT_MANLY); /* "Response from server is not long enough to hold header" */ /* Allocate the string "get" */ if((get = js_create(length + 7,1)) == 0) harderror(L_NO_GET); /* "Could not allocate memory for get string" */ if((expand = js_create((length + 7) * 4,1)) == 0) harderror(L_NO_EXPAND); /* "Could not allocate memory for expand string" */ if((length = recv(sock,get->string,length,MSG_WAITALL)) == -1) harderror(L_SERVER); /* "Could not get packet from server" */ get->unit_count = length; show_esc_stdout(get); printf("\n"); fflush(stdout); js_destroy(get); } return 0; /* Success */ }