#if !defined(lint) && !defined(SABER) static char rcsid[] = "$Id: res_update.c,v 1.1.1.1 2003/11/19 01:51:39 kyu3 Exp $"; #endif /* not lint */ /* * Copyright (c) 1996 by Internet Software Consortium. * * 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. * * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE * CONSORTIUM 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. */ /* * Portions copyright (c) 1999, 2000 * Intel Corporation. * 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 Intel Corporation and * its contributors. * * 4. Neither the name of Intel Corporation or its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY INTEL CORPORATION 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 INTEL CORPORATION 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. * */ /* * Based on the Dynamic DNS reference implementation by Viraj Bais * */ #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Separate a linked list of records into groups so that all records * in a group will belong to a single zone on the nameserver. * Create a dynamic update packet for each zone and send it to the * nameservers for that zone, and await answer. * Abort if error occurs in updating any zone. * Return the number of zones updated on success, < 0 on error. * * On error, caller must deal with the unsynchronized zones * eg. an A record might have been successfully added to the forward * zone but the corresponding PTR record would be missing if error * was encountered while updating the reverse zone. */ #define NSMAX 16 struct ns1 { char nsname[MAXDNAME]; struct in_addr nsaddr1; }; struct zonegrp { char z_origin[MAXDNAME]; int16_t z_class; char z_soardata[MAXDNAME + 5 * INT32SZ]; struct ns1 z_ns[NSMAX]; int z_nscount; ns_updrec * z_rr; struct zonegrp *z_next; }; int res_update(ns_updrec *rrecp_in) { ns_updrec *rrecp, *tmprrecp; u_char buf[PACKETSZ], answer[PACKETSZ], packet[2*PACKETSZ]; char name[MAXDNAME], zname[MAXDNAME], primary[MAXDNAME], mailaddr[MAXDNAME]; u_char soardata[2*MAXCDNAME+5*INT32SZ]; char *dname, *svdname, *cp1, *target; u_char *cp, *eom; HEADER *hp = (HEADER *) answer; struct zonegrp *zptr = NULL, *tmpzptr, *prevzptr, *zgrp_start = NULL; int i, j, k = 0, n, ancount, nscount, arcount, rcode, rdatasize, newgroup, done, myzone, seen_before, numzones = 0; u_int16_t dlen, class, qclass, type, qtype; u_int32_t ttl; if ((_res.options & RES_INIT) == 0 && res_init() == -1) { h_errno = NETDB_INTERNAL; return (-1); } for (rrecp = rrecp_in; rrecp; rrecp = rrecp->r_next) { dname = rrecp->r_dname; n = (int)strlen(dname); if (dname[n-1] == '.') dname[n-1] = '\0'; qtype = T_SOA; qclass = rrecp->r_class; done = 0; seen_before = 0; while (!done && dname) { if (qtype == T_SOA) { for (tmpzptr = zgrp_start; tmpzptr && !seen_before; tmpzptr = tmpzptr->z_next) { if (strcasecmp(dname, tmpzptr->z_origin) == 0 && tmpzptr->z_class == qclass) seen_before++; for (tmprrecp = tmpzptr->z_rr; tmprrecp && !seen_before; tmprrecp = tmprrecp->r_grpnext) if (strcasecmp(dname, tmprrecp->r_dname) == 0 && tmprrecp->r_class == qclass) { seen_before++; break; } if (seen_before) { /* * Append to the end of * current group. */ for (tmprrecp = tmpzptr->z_rr; tmprrecp->r_grpnext; tmprrecp = tmprrecp->r_grpnext) (void)NULL; tmprrecp->r_grpnext = rrecp; rrecp->r_grpnext = NULL; done = 1; break; } } } else if (qtype == T_A) { for (tmpzptr = zgrp_start; tmpzptr && !done; tmpzptr = tmpzptr->z_next) for (i = 0; i < tmpzptr->z_nscount; i++) if (tmpzptr->z_class == qclass && strcasecmp(tmpzptr->z_ns[i].nsname, dname) == 0 && tmpzptr->z_ns[i].nsaddr1.s_addr != 0) { zptr->z_ns[k].nsaddr1.s_addr = tmpzptr->z_ns[i].nsaddr1.s_addr; done = 1; break; } } if (done) break; n = res_mkquery(QUERY, dname, qclass, qtype, NULL, 0, NULL, buf, sizeof buf); if (n <= 0) { fprintf(stderr, "res_update: mkquery failed\n"); return (n); } n = res_send(buf, n, answer, sizeof answer); if (n < 0) { fprintf(stderr, "res_update: send error for %s\n", rrecp->r_dname); return (n); } if (n < HFIXEDSZ) return (-1); ancount = ntohs(hp->ancount); nscount = ntohs(hp->nscount); arcount = ntohs(hp->arcount); rcode = hp->rcode; cp = answer + HFIXEDSZ; eom = answer + n; /* skip the question section */ n = dn_skipname(cp, eom); if (n < 0 || cp + n + 2 * INT16SZ > eom) return (-1); cp += n + 2 * INT16SZ; if (qtype == T_SOA) { if (ancount == 0 && nscount == 0 && arcount == 0) { /* * if (rcode == NOERROR) then the dname exists but * has no soa record associated with it. * if (rcode == NXDOMAIN) then the dname does not * exist and the server is replying out of NCACHE. * in either case, proceed with the next try */ dname = strchr(dname, '.'); if (dname != NULL) dname++; continue; } else if ((rcode == NOERROR || rcode == NXDOMAIN) && ancount == 0 && nscount == 1 && arcount == 0) { /* * name/data does not exist, soa record supplied in the * authority section */ /* authority section must contain the soa record */ if ((n = dn_expand(answer, eom, cp, zname, sizeof zname)) < 0) return (n); cp += n; if (cp + 2 * INT16SZ > eom) return (-1); GETSHORT(type, cp); GETSHORT(class, cp); if (type != T_SOA || class != qclass) { fprintf(stderr, "unknown answer\n"); return (-1); } myzone = 0; svdname = dname; while (dname) if (strcasecmp(dname, zname) == 0) { myzone = 1; break; } else if ((dname = strchr(dname, '.')) != NULL) dname++; if (!myzone) { dname = strchr(svdname, '.'); if (dname != NULL) dname++; continue; } nscount = 0; /* fallthrough */ } else if (rcode == NOERROR && ancount == 1) { /* * found the zone name * new servers will supply NS records for the zone * in authority section and A records for those * nameservers in the additional section * older servers have to be explicitly queried for * NS records for the zone */ /* answer section must contain the soa record */ if ((n = dn_expand(answer, eom, cp, zname, sizeof zname)) < 0) return (n); else cp += n; if (cp + 2 * INT16SZ > eom) return (-1); GETSHORT(type, cp); GETSHORT(class, cp); if (type == T_CNAME) { dname = strchr(dname, '.'); if (dname != NULL) dname++; continue; } if (strcasecmp(dname, zname) != 0 || type != T_SOA || class != rrecp->r_class) { fprintf(stderr, "unknown answer\n"); return (-1); } /* FALLTHROUGH */ } else { fprintf(stderr, "unknown response: ans=%d, auth=%d, add=%d, rcode=%d\n", ancount, nscount, arcount, hp->rcode); return (-1); } if (cp + INT32SZ + INT16SZ > eom) return (-1); /* continue processing the soa record */ GETLONG(ttl, cp); GETSHORT(dlen, cp); if (cp + dlen > eom) return (-1); newgroup = 1; zptr = zgrp_start; prevzptr = NULL; while (zptr) { if (strcasecmp(zname, zptr->z_origin) == 0 && type == T_SOA && class == qclass) { newgroup = 0; break; } prevzptr = zptr; zptr = zptr->z_next; } if (!newgroup) { for (tmprrecp = zptr->z_rr; tmprrecp->r_grpnext; tmprrecp = tmprrecp->r_grpnext) ; tmprrecp->r_grpnext = rrecp; rrecp->r_grpnext = NULL; done = 1; cp += dlen; break; } else { if ((n = dn_expand(answer, eom, cp, primary, sizeof primary)) < 0) return (n); cp += n; /* * We don't have to bounds check here because the * next use of 'cp' is in dn_expand(). */ cp1 = (char *)soardata; strcpy(cp1, primary); cp1 += strlen(cp1) + 1; if ((n = dn_expand(answer, eom, cp, mailaddr, sizeof mailaddr)) < 0) return (n); cp += n; strcpy(cp1, mailaddr); cp1 += strlen(cp1) + 1; if (cp + 5*INT32SZ > eom) return (-1); memcpy(cp1, cp, 5*INT32SZ); cp += 5*INT32SZ; cp1 += 5*INT32SZ; rdatasize = (int)((u_char *)cp1 - soardata); zptr = calloc(1, sizeof(struct zonegrp)); if (zptr == NULL) return (-1); if (zgrp_start == NULL) zgrp_start = zptr; else prevzptr->z_next = zptr; zptr->z_rr = rrecp; rrecp->r_grpnext = NULL; strcpy(zptr->z_origin, zname); zptr->z_class = class; memcpy(zptr->z_soardata, soardata, rdatasize); /* fallthrough to process NS and A records */ } } else if (qtype == T_NS) { if (rcode == NOERROR && ancount > 0) { strcpy(zname, dname); for (zptr = zgrp_start; zptr; zptr = zptr->z_next) { if (strcasecmp(zname, zptr->z_origin) == 0) break; } if (zptr == NULL) /* should not happen */ return (-1); if (nscount > 0) { /* * answer and authority sections contain * the same information, skip answer section */ for (j = 0; j < ancount; j++) { n = dn_skipname(cp, eom); if (n < 0) return (-1); n += 2*INT16SZ + INT32SZ; if (cp + n + INT16SZ > eom) return (-1); cp += n; GETSHORT(dlen, cp); cp += dlen; } } else nscount = ancount; /* fallthrough to process NS and A records */ } else { fprintf(stderr, "cannot determine nameservers for %s:\ ans=%d, auth=%d, add=%d, rcode=%d\n", dname, ancount, nscount, arcount, hp->rcode); return (-1); } } else if (qtype == T_A) { if (rcode == NOERROR && ancount > 0) { arcount = ancount; ancount = nscount = 0; /* fallthrough to process A records */ } else { fprintf(stderr, "cannot determine address for %s:\ ans=%d, auth=%d, add=%d, rcode=%d\n", dname, ancount, nscount, arcount, hp->rcode); return (-1); } } /* process NS records for the zone */ j = 0; for (i = 0; i < nscount; i++) { if ((n = dn_expand(answer, eom, cp, name, sizeof name)) < 0) return (n); cp += n; if (cp + 3 * INT16SZ + INT32SZ > eom) return (-1); GETSHORT(type, cp); GETSHORT(class, cp); GETLONG(ttl, cp); GETSHORT(dlen, cp); if (cp + dlen > eom) return (-1); if (strcasecmp(name, zname) == 0 && type == T_NS && class == qclass) { if ((n = dn_expand(answer, eom, cp, name, sizeof name)) < 0) return (n); target = zptr->z_ns[j++].nsname; strcpy(target, name); } cp += dlen; } if (zptr->z_nscount == 0) zptr->z_nscount = j; /* get addresses for the nameservers */ for (i = 0; i < arcount; i++) { if ((n = dn_expand(answer, eom, cp, name, sizeof name)) < 0) return (n); cp += n; if (cp + 3 * INT16SZ + INT32SZ > eom) return (-1); GETSHORT(type, cp); GETSHORT(class, cp); GETLONG(ttl, cp); GETSHORT(dlen, cp); if (cp + dlen > eom) return (-1); if (type == T_A && dlen == INT32SZ && class == qclass) { for (j = 0; j < zptr->z_nscount; j++) if (strcasecmp(name, zptr->z_ns[j].nsname) == 0) { memcpy(&zptr->z_ns[j].nsaddr1.s_addr, cp, INT32SZ); break; } } cp += dlen; } if (zptr->z_nscount == 0) { dname = zname; qtype = T_NS; continue; } done = 1; for (k = 0; k < zptr->z_nscount; k++) if (zptr->z_ns[k].nsaddr1.s_addr == 0) { done = 0; dname = zptr->z_ns[k].nsname; qtype = T_A; } } /* while */ } _res.options |= RES_DEBUG; for (zptr = zgrp_start; zptr; zptr = zptr->z_next) { /* append zone section */ rrecp = res_mkupdrec(ns_s_zn, zptr->z_origin, zptr->z_class, ns_t_soa, 0); if (rrecp == NULL) { fprintf(stderr, "saverrec error\n"); fflush(stderr); return (-1); } rrecp->r_grpnext = zptr->z_rr; zptr->z_rr = rrecp; n = res_mkupdate(zptr->z_rr, packet, sizeof packet); if (n < 0) { fprintf(stderr, "res_mkupdate error\n"); fflush(stderr); return (-1); } else fprintf(stdout, "res_mkupdate: packet size = %d\n", n); /* * Override the list of NS records from res_init() with * the authoritative nameservers for the zone being updated. * Sort primary to be the first in the list of nameservers. */ for (i = 0; i < zptr->z_nscount; i++) { if (strcasecmp(zptr->z_ns[i].nsname, zptr->z_soardata) == 0) { struct in_addr tmpaddr; if (i != 0) { strcpy(zptr->z_ns[i].nsname, zptr->z_ns[0].nsname); strcpy(zptr->z_ns[0].nsname, zptr->z_soardata); tmpaddr = zptr->z_ns[i].nsaddr1; zptr->z_ns[i].nsaddr1 = zptr->z_ns[0].nsaddr1; zptr->z_ns[0].nsaddr1 = tmpaddr; } break; } } for (i = 0; i < MAXNS; i++) { _res.nsaddr_list[i].sin_addr = zptr->z_ns[i].nsaddr1; _res.nsaddr_list[i].sin_family = AF_INET; _res.nsaddr_list[i].sin_port = htons(NAMESERVER_PORT); } _res.nscount = (zptr->z_nscount < MAXNS) ? zptr->z_nscount : MAXNS; n = res_send(packet, n, answer, sizeof(answer)); if (n < 0) { fprintf(stderr, "res_send: send error, n=%d\n", n); break; } else numzones++; } /* free malloc'ed memory */ while(zgrp_start) { zptr = zgrp_start; zgrp_start = zgrp_start->z_next; res_freeupdrec(zptr->z_rr); /* Zone section we allocated. */ free((char *)zptr); } return (numzones); }