1 /* 2 * pythonmod_utils.c: utilities used by wrapper 3 * 4 * Copyright (c) 2009, Zdenek Vasicek (vasicek AT fit.vutbr.cz) 5 * Marek Vavrusa (xvavru00 AT stud.fit.vutbr.cz) 6 * 7 * This software is open source. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * * Redistributions of source code must retain the above copyright notice, 14 * this list of conditions and the following disclaimer. 15 * 16 * * Redistributions in binary form must reproduce the above copyright notice, 17 * this list of conditions and the following disclaimer in the documentation 18 * and/or other materials provided with the distribution. 19 * 20 * * Neither the name of the organization nor the names of its 21 * contributors may be used to endorse or promote products derived from this 22 * software without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 25 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 26 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 27 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE 28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34 * POSSIBILITY OF SUCH DAMAGE. 35 */ 36 /** 37 * \file 38 * Utility functions for the python module that perform stores and loads and 39 * conversions. 40 */ 41 #include "config.h" 42 #include "pythonmod/pythonmod_utils.h" 43 #include "util/module.h" 44 #include "util/netevent.h" 45 #include "util/net_help.h" 46 #include "services/cache/dns.h" 47 #include "services/cache/rrset.h" 48 #include "util/data/msgparse.h" 49 #include "util/data/msgreply.h" 50 #include "util/storage/slabhash.h" 51 #include "util/regional.h" 52 #include "iterator/iter_delegpt.h" 53 #include "sldns/sbuffer.h" 54 55 #undef _POSIX_C_SOURCE 56 #undef _XOPEN_SOURCE 57 #include <Python.h> 58 59 /* Store the reply_info and query_info pair in message cache (qstate->msg_cache) */ 60 int storeQueryInCache(struct module_qstate* qstate, struct query_info* qinfo, struct reply_info* msgrep, int is_referral) 61 { 62 if (!msgrep) 63 return 0; 64 65 if (msgrep->authoritative) /*authoritative answer can't be stored in cache*/ 66 { 67 PyErr_SetString(PyExc_ValueError, "Authoritative answer can't be stored"); 68 return 0; 69 } 70 71 return dns_cache_store(qstate->env, qinfo, msgrep, is_referral, 72 qstate->prefetch_leeway, 0, NULL, qstate->query_flags); 73 } 74 75 /* Invalidate the message associated with query_info stored in message cache */ 76 void invalidateQueryInCache(struct module_qstate* qstate, struct query_info* qinfo) 77 { 78 hashvalue_type h; 79 struct lruhash_entry* e; 80 struct reply_info *r; 81 size_t i, j; 82 83 h = query_info_hash(qinfo, qstate->query_flags); 84 if ((e=slabhash_lookup(qstate->env->msg_cache, h, qinfo, 0))) 85 { 86 r = (struct reply_info*)(e->data); 87 if (r) 88 { 89 r->ttl = 0; 90 if(rrset_array_lock(r->ref, r->rrset_count, *qstate->env->now)) { 91 for(i=0; i< r->rrset_count; i++) 92 { 93 struct packed_rrset_data* data = 94 (struct packed_rrset_data*) r->ref[i].key->entry.data; 95 if(i>0 && r->ref[i].key == r->ref[i-1].key) 96 continue; 97 98 data->ttl = r->ttl; 99 for(j=0; j<data->count + data->rrsig_count; j++) 100 data->rr_ttl[j] = r->ttl; 101 } 102 rrset_array_unlock(r->ref, r->rrset_count); 103 } 104 } 105 lock_rw_unlock(&e->lock); 106 } else { 107 log_info("invalidateQueryInCache: qinfo is not in cache"); 108 } 109 } 110 111 /* Create response according to the ldns packet content */ 112 int createResponse(struct module_qstate* qstate, sldns_buffer* pkt) 113 { 114 struct msg_parse* prs; 115 struct edns_data edns; 116 117 /* parse message */ 118 prs = (struct msg_parse*) regional_alloc(qstate->env->scratch, sizeof(struct msg_parse)); 119 if (!prs) { 120 log_err("storeResponse: out of memory on incoming message"); 121 return 0; 122 } 123 124 memset(prs, 0, sizeof(*prs)); 125 memset(&edns, 0, sizeof(edns)); 126 127 sldns_buffer_set_position(pkt, 0); 128 if (parse_packet(pkt, prs, qstate->env->scratch) != LDNS_RCODE_NOERROR) { 129 verbose(VERB_ALGO, "storeResponse: parse error on reply packet"); 130 return 0; 131 } 132 /* edns is not examined, but removed from message to help cache */ 133 if(parse_extract_edns(prs, &edns, qstate->env->scratch) != 134 LDNS_RCODE_NOERROR) 135 return 0; 136 137 /* remove CD-bit, we asked for in case we handle validation ourself */ 138 prs->flags &= ~BIT_CD; 139 140 /* allocate response dns_msg in region */ 141 qstate->return_msg = (struct dns_msg*)regional_alloc(qstate->region, sizeof(struct dns_msg)); 142 if (!qstate->return_msg) 143 return 0; 144 145 memset(qstate->return_msg, 0, sizeof(*qstate->return_msg)); 146 if(!parse_create_msg(pkt, prs, NULL, &(qstate->return_msg)->qinfo, &(qstate->return_msg)->rep, qstate->region)) { 147 log_err("storeResponse: malloc failure: allocating incoming dns_msg"); 148 return 0; 149 } 150 151 /* Make sure that the RA flag is set (since the presence of 152 * this module means that recursion is available) */ 153 /* qstate->return_msg->rep->flags |= BIT_RA; */ 154 155 /* Clear the AA flag */ 156 /* FIXME: does this action go here or in some other module? */ 157 /*qstate->return_msg->rep->flags &= ~BIT_AA; */ 158 159 /* make sure QR flag is on */ 160 /*qstate->return_msg->rep->flags |= BIT_QR; */ 161 162 if(verbosity >= VERB_ALGO) 163 log_dns_msg("storeResponse: packet:", &qstate->return_msg->qinfo, qstate->return_msg->rep); 164 165 return 1; 166 } 167 168 169 /* Convert reply->addr to string */ 170 void reply_addr2str(struct comm_reply* reply, char* dest, int maxlen) 171 { 172 int af = (int)((struct sockaddr_in*) &(reply->addr))->sin_family; 173 void* sinaddr = &((struct sockaddr_in*) &(reply->addr))->sin_addr; 174 175 if(af == AF_INET6) 176 sinaddr = &((struct sockaddr_in6*)&(reply->addr))->sin6_addr; 177 dest[0] = 0; 178 if (inet_ntop(af, sinaddr, dest, (socklen_t)maxlen) == 0) 179 return; 180 dest[maxlen-1] = 0; 181 } 182 183 /* Convert target->addr to string */ 184 void delegpt_addr_addr2str(struct delegpt_addr* target, char *dest, int maxlen) 185 { 186 int af = (int)((struct sockaddr_in*) &(target->addr))->sin_family; 187 void* sinaddr = &((struct sockaddr_in*) &(target->addr))->sin_addr; 188 189 if(af == AF_INET6) 190 sinaddr = &((struct sockaddr_in6*)&(target->addr))->sin6_addr; 191 dest[0] = 0; 192 if (inet_ntop(af, sinaddr, dest, (socklen_t)maxlen) == 0) 193 return; 194 dest[maxlen-1] = 0; 195 } 196