+
+#ifdef HAS_HESIOD_RELOAD
+/*
+ * Zone transfer...
+ */
+
+#define MAXHSNS 8
+#define MAX_NSADDR 16
+
+static char *hs_domain;
+static mnt_map *hs_map;
+static int hs_nscount;
+static char nsaddr_list[MAX_NSADDR][sizeof(struct in_addr)];
+
+int hesiod_reload P((mnt_map *m, char *map, void (*fn)()));
+int hesiod_reload(m, map, fn)
+mnt_map *m;
+char *map;
+void (*fn)();
+{
+ char hes_map[MAXPATHLEN];
+ char *zone_name, *cp;
+ short domainlen;
+ int status;
+
+#ifdef DEBUG
+ dlog("hesiod_reload (%x %s %x)", m, map, fn);
+#endif DEBUG
+ if (status = res_init()) {
+#ifdef DEBUG
+ dlog("hesiod_reload: res_init failed with %d", status);
+#endif
+ return(status);
+ }
+ _res.retrans = 90;
+ hs_map = m;
+ domainlen = strlen(hostdomain);
+ MAKE_HES_NAME(hes_map, map);
+ zone_name = hes_to_bind("", hes_map);
+ if (*zone_name == '.')
+ zone_name++;
+ hs_domain = zone_name;
+ /* Traverse the DNS tree until we find an SOA we can transfer from.
+ (Our initial zone_name is likely to just be a subtree of a
+ real zone). */
+ do {
+ /* If we can't find any NS records, go up a level in the
+ DNS tree */
+ if (hs_get_ns_list(zone_name) == 0 &&
+ hs_zone_transfer(zone_name) == 0)
+ return(0);
+ /* Move up DNS tree by one component */
+ if (cp = strchr(zone_name, '.'))
+ zone_name = ++cp;
+ else
+ break;
+ } while (strlen(zone_name) >= domainlen);
+#ifdef DEBUG
+ dlog("hesiod_reload: Giving up on %s", hs_domain);
+#endif
+ return(-1);
+}
+
+hs_zone_transfer(domain)
+char *domain;
+{
+ int status, len;
+ char buf[PACKETSZ];
+ /* Want to make sure ansbuf is well alligned */
+ long ansbuf[PACKETSZ/sizeof(long)];
+
+#ifdef DEBUG
+ dlog("hs_zone_transfer (%s)", domain);
+#endif
+ if ((len = res_mkquery(QUERY, domain, C_HS, T_AXFR,
+ (char *)NULL, 0, NULL, buf, PACKETSZ)) == -1) {
+#ifdef DEBUG
+ dlog("hs_zone_transfer: res_mkquery failed");
+#endif
+ errno = 0;
+ return(-1);
+ }
+ if ((status = hs_res_send(buf, len, (char *)ansbuf, PACKETSZ)) == -1) {
+#ifdef DEBUG
+ dlog("hs_zone_transfer: hs_res_send failed. status %d errno %d",
+ status, errno);
+#endif
+ errno = 0;
+ return(-1);
+ }
+ return(0);
+}
+
+#define hs_server_addr(ns) ((struct in_addr *) nsaddr_list[ns])
+
+hs_res_send(buf, buflen, answer, anslen)
+char *buf;
+int buflen;
+char *answer;
+int anslen;
+{
+ int retry, ns;
+ u_short id, len;
+ HEADER *hp = (HEADER *) buf;
+ struct iovec iov[2];
+ static int s = -1;
+ int status;
+ struct sockaddr_in server;
+
+ soacnt = 0;
+ id = hp->id;
+ /*
+ * Send request, RETRY times, or until successful
+ */
+ for (retry = _res.retry; retry > 0; retry--) {
+ for (ns = 0; ns < hs_nscount; ns++) {
+ hs_timeout.tv_sec =
+ (_res.retrans << (_res.retry - retry))
+ / hs_nscount;
+ if (hs_timeout.tv_sec <= 0)
+ hs_timeout.tv_sec = 1;
+ hs_timeout.tv_usec = 0;
+ if (s < 0) {
+ s = socket(AF_INET, SOCK_STREAM, 0);
+ if (s < 0) {
+ continue;
+ }
+ servernum = ns;
+ bcopy(hs_server_addr(ns), &server.sin_addr,
+ sizeof(struct in_addr));
+ server.sin_family = AF_INET;
+ server.sin_port = htons(NAMESERVER_PORT);
+
+ if (connect(s, &server,
+ sizeof(struct sockaddr)) < 0) {
+ (void) close(s);
+ s = -1;
+ continue;
+ }
+ }
+ /*
+ * Send length & message
+ */
+ len = htons((u_short)buflen);
+ iov[0].iov_base = (caddr_t)&len;
+ iov[0].iov_len = sizeof(len);
+ iov[1].iov_base = buf;
+ iov[1].iov_len = buflen;
+ if (writev(s, iov, 2) != sizeof(len) + buflen) {
+ (void) close(s);
+ s = -1;
+ continue;
+ }
+ status = 0;
+ while (s != -1 && soacnt < 2 && status != -2) {
+ if ((status =
+ hs_readresp(s, answer, anslen)) == -1) {
+ (void) close(s);
+ s = -1;
+ continue;
+ }
+ }
+ if (status == -2) {
+ /* There was a permanent error transfering this
+ zone. Give up. */
+ if (s != -1) {
+ (void) close(s);
+ s = -1;
+ }
+ return(-1);
+ }
+ if (s == -1)
+ continue;
+ return (0);
+ }
+ }
+ if (errno == 0)
+ errno = ETIMEDOUT;
+ return (-1);
+}
+
+/* Returns:
+ 0: Success
+ -1: Error
+ -2: Permanent failure
+*/
+hs_readresp(s, answer, anslen)
+int s;
+char *answer;
+int anslen;
+{
+ register int len, n;
+ char *cp;
+
+ cp = answer;
+ len = sizeof(short);
+ while (len != 0 &&
+ (n = hs_res_vcread(s, (char *)cp, (int)len, &hs_timeout)) > 0) {
+ cp += n;
+ len -= n;
+ }
+ if (n <= 0)
+ return(-1);
+ cp = answer;
+ if ((len = _getshort(cp)) > anslen) {
+#ifdef DEBUG
+ dlog("hs_readresp: response too long: %d", len);
+#endif
+ return(-1);
+ }
+ while (len != 0 &&
+ (n = hs_res_vcread(s, (char *)cp, (int)len, &hs_timeout)) > 0) {
+ cp += n;
+ len -= n;
+ }
+ if (n <= 0)
+ return(-1);
+ return(hs_parse(answer, answer+PACKETSZ));
+}
+
+hs_res_vcread(sock, buf, buflen, timeout)
+int sock, buflen;
+char *buf;
+struct timeval *timeout;
+{
+ register int n;
+
+ if ((n = hs_res_selwait(sock, timeout)) > 0)
+ return(read(sock, buf, buflen));
+ else
+ return(n);
+}
+
+hs_res_selwait(sock, timeout)
+int sock;
+struct timeval *timeout;
+{
+ fd_set dsmask;
+ register int n;
+
+ /*
+ * Wait for reply
+ */
+ FD_ZERO(&dsmask);
+ FD_SET(sock, &dsmask);
+ n = select(sock+1, &dsmask, (fd_set *)NULL,
+ (fd_set *)NULL, timeout);
+ return(n);
+}
+
+/* Returns:
+ 0: Success
+ -1: Error
+ -2: Permanent failure
+*/
+hs_parse(msg, eom)
+char *msg, *eom;
+{
+ register char *cp;
+ register HEADER *hp;
+ register int n, len;
+ int qdcount, ancount;
+ char key[PACKETSZ];
+ char *key_cpy, *value, *hs_make_value();
+ short type;
+
+ hp = (HEADER *)msg;
+ if (hp->rcode != NOERROR || hp->opcode != QUERY) {
+ char dq[20];
+#ifdef DEBUG
+ dlog("Bad response (%d) from nameserver %s", hp->rcode, inet_dquad(dq, hs_server_addr(servernum)->s_addr));
+#endif DEBUG
+ return(-1);
+ }
+ cp = msg + sizeof(HEADER);
+ ancount = ntohs(hp->ancount);
+ qdcount = ntohs(hp->qdcount);
+ while (qdcount-- > 0)
+ cp += dn_skipname(cp, eom) + QFIXEDSZ;
+ if (soacnt == 0 && ancount == 0) {
+ /* XXX We should look for NS records to find SOA */
+#ifdef DEBUG
+ dlog("No SOA found");
+#endif
+ return(-2);
+ }
+ while (ancount-- > 0 && cp < eom) {
+ if ((n = dn_expand(msg, eom, cp, key, PACKETSZ)) < 0)
+ break;
+ cp += n;
+ if ((type = _getshort(cp)) == T_SOA) {
+ soacnt++;
+ }
+ cp += 2*sizeof(u_short) + sizeof(u_long);
+ len = _getshort(cp);
+ cp += sizeof(u_short);
+ /* Check to see if key is in our domain */
+ if (type == T_TXT && hs_strip_our_domain(key)) {
+ value = hs_make_value(cp, len);
+ if (value == NULL)
+ return(-1);
+ key_cpy = strdup(key);
+#ifdef DEBUG
+ dlog("hs_parse: Parsed key: %s, value: %s", key,
+ value);
+#endif
+ mapc_add_kv(hs_map, key_cpy, value);
+ }
+ cp += len;
+ errno = 0;
+ }
+ return(0);
+}
+
+/* Check to see if the domain name in the supplied argument matches
+ hs_domain. Strip hs_domain from supplied argument if so. */
+hs_strip_our_domain(name)
+char *name;
+{
+ char *end_pos;
+ short targ_len, cur_len;
+
+ targ_len = strlen(hs_domain);
+ cur_len = strlen(name);
+ if (cur_len <= targ_len)
+ return(0);
+ end_pos = &name[cur_len - targ_len];
+ if (strcmp(end_pos, hs_domain) != 0)
+ return(0);
+ if (*--end_pos != '.')
+ return(0);
+ *end_pos = '\0';
+ return(1);
+}
+
+#define MAXDATA 8*1024
+
+char *
+hs_make_value(cp, len)
+char *cp;
+int len;
+{
+ char *value, *cpcpy, *valuep;
+ int cnt, nextcnt, totalcnt, lencpy;
+#ifdef DEBUG
+ char *dbgname;
+
+ dbgname = &cp[1];
+#endif DEBUG
+
+ lencpy = len;
+ cpcpy = cp;
+ totalcnt = 0;
+ cnt = *cpcpy++;
+ while (cnt) {
+ totalcnt += cnt;
+ lencpy -= cnt+1;
+ if (lencpy == 0)
+ break;
+ nextcnt = cpcpy[cnt];
+ cpcpy = &cpcpy[cnt+1];
+ cnt = nextcnt;
+ }
+ if (totalcnt < 1 || totalcnt > MAXDATA || totalcnt > len) {
+#ifdef DEBUG
+ dlog("TXT RR not of expected length (%d %d): %s", totalcnt,
+ len, dbgname);
+#endif DEBUG
+ return(NULL);
+ }
+ /* Allocate null terminated string */
+ value = (char *) xmalloc(totalcnt+1);
+ value[totalcnt] = '\0';
+ cnt = *cp++;
+ valuep = value;
+ while (cnt) {
+ bcopy(cp, valuep, cnt);
+ len -= cnt+1;
+ if (len == 0)
+ break;
+ valuep = &valuep[cnt];
+ nextcnt = cp[cnt];
+ cp = &cp[cnt+1];
+ cnt = nextcnt;
+ }
+ return(value);
+}
+
+hs_make_ns_query(domain, ansbuf)
+char *domain;
+char *ansbuf;
+{
+ int status, len;
+ char buf[PACKETSZ];
+
+ if ((len = res_mkquery(QUERY, domain, C_HS, T_NS,
+ (char *)NULL, 0, NULL, buf, PACKETSZ)) == -1) {
+#ifdef DEBUG
+ dlog("hs_get_ns_list: res_mkquery failed");
+#endif
+ errno = 0;
+ return(-1);
+ }
+ if ((status = res_send(buf, len, (char *)ansbuf, PACKETSZ)) == -1) {
+#ifdef DEBUG
+ dlog("hs_get_ns_list: res_send failed. status %d errno %d",
+ status, errno);
+#endif
+ errno = 0;
+ return(-1);
+ }
+ return(0);
+}
+
+static void
+add_address(addr)
+struct in_addr *addr;
+{
+ char dq[20];
+ bcopy((char *)addr, nsaddr_list[hs_nscount++], sizeof(struct in_addr));
+#ifdef DEBUG
+ dlog("Adding NS address %s", inet_dquad(dq, addr->s_addr));
+#endif DEBUG
+}
+
+hs_get_ns_list(domain)
+char *domain;
+{
+ register HEADER *hp;
+ int qdcount, nscount;
+ register char *cp;
+ register int n, len;
+ char key[PACKETSZ], name[PACKETSZ], msg[PACKETSZ], *eom;
+ register long **hptr;
+ struct hostent *ghp;
+ int numns;
+ char nsname[MAXHSNS][MAXDATA];
+ int nshaveaddr[MAXHSNS], i;
+ short type;
+
+ if (hs_make_ns_query(domain, msg) == -1)
+ return(-1);
+ numns = hs_nscount = 0;
+ eom = &msg[PACKETSZ];
+ bzero(nsname, sizeof(nsname));
+ hp = (HEADER *)msg;
+ if (hp->rcode != NOERROR || hp->opcode != QUERY) {
+#ifdef DEBUG
+ dlog("Bad response (%d) from nameserver %#x", hp->rcode,
+ hs_server_addr(servernum)->s_addr);
+#endif DEBUG
+ return(-1);
+ }
+ cp = msg + sizeof(HEADER);
+ qdcount = ntohs(hp->qdcount);
+ while (qdcount-- > 0)
+ cp += dn_skipname(cp, eom) + QFIXEDSZ;
+ nscount = ntohs(hp->ancount) + ntohs(hp->nscount) + ntohs(hp->arcount);
+#ifdef DEBUG
+ dlog("hs_get_ns_list: Processing %d response records", nscount);
+#endif
+ for (;nscount; nscount--) {
+ if ((n = dn_expand(msg, eom, cp, key, PACKETSZ)) < 0)
+ break;
+ cp += n;
+ type = _getshort(cp);
+ cp += 2*sizeof(u_short) + sizeof(u_long);
+ len = _getshort(cp);
+ cp += sizeof(u_short);
+#ifdef DEBUG
+ dlog("hs_get_ns_list: Record type: %d", type);
+#endif
+ switch (type) {
+ case T_NS:
+ if (numns >= MAXHSNS || strcasecmp(domain, key) != 0)
+ break;
+ if ((n = dn_expand(msg, eom, cp, name, PACKETSZ)) < 0)
+ break;
+#ifdef DEBUG
+ dlog("hs_get_ns_list: NS name: %s", name);
+#endif
+ for (i = 0; i < numns; i++)
+ if (strcasecmp(nsname[i], name) == 0)
+ break;
+ if (i == numns) {
+#ifdef DEBUG
+ dlog("hs_get_ns_list: Saving name %s", name);
+#endif
+ strncpy(nsname[numns], name, MAXDATA);
+ nshaveaddr[numns] = 0;
+ numns++;
+ }
+ break;
+ case T_A:
+ if (hs_nscount == MAX_NSADDR)
+ break;
+ for (i = 0; i < numns; i++) {
+ if (strcasecmp(nsname[i], domain) == 0) {
+ nshaveaddr[i]++;
+ add_address((struct in_addr *) cp);
+ break;
+ }
+ }
+ break;
+ default:
+ break;
+ }
+ if (hs_nscount == MAX_NSADDR)
+ break;
+ cp += len;
+ errno = 0;
+ }
+#ifdef DEBUG
+ dlog("hs_get_ns_list: Found %d NS records", numns);
+#endif
+ for (i = 0; i < numns; i++) {
+ if (nshaveaddr[i])
+ continue;
+ if ((ghp = gethostbyname(nsname[i])) == 0)
+ continue;
+ for (hptr = (long **)ghp->h_addr_list;
+ *hptr && hs_nscount < MAX_NSADDR; hptr++) {
+ add_address((struct in_addr *) *hptr);
+ }
+ }
+ if (hs_nscount)
+ return(0);
+#ifdef DEBUG
+ dlog("No NS records found for %s", domain);
+ return(-1);
+#endif DEBUG
+}
+#endif /* HAS_HESIOD_RELOAD */
projects / unix-history / commitdiff