1 /* RFC2136 DNS inform - necessary for Win2k3 DNS servers */
15 [1] "request format error",
16 [2] "internal server error",
17 [3] "domain name does not exist",
18 [4] "request not supported",
19 [5] "permission denied",
20 [6] "domain name already exists",
21 [7] "resource record already exists",
22 [8] "resource record does not exist",
23 [9] "server not authoritative",
24 [10] "domain name not in zone",
30 fprint(2, "usage: %s [-x netmtpt]\n", argv0);
35 ding(void *, char *msg)
37 if(strstr(msg, "alarm") != nil)
69 pmem(uchar **p, void *v, int len)
76 pname(uchar **p, char *s)
82 while(*s && *s != '.')
92 main(int argc, char *argv[])
96 char *sysname, *dnsdomain, *dom, *inform, *ns, net[32];
97 uchar *p, buf[4096], addr[IPv4addrlen], v6addr[IPaddrlen];
101 static char *query[] = { "dom", "dnsdomain", "ns", "inform" };
103 fmtinstall('I', eipfmt);
104 fmtinstall('V', eipfmt);
105 setnetmtpt(net, sizeof net, nil);
117 setnetmtpt(net, sizeof net, EARGF(usage()));
126 if((sysname = getenv("sysname")) == nil)
127 sysfatal("$sysname not set");
129 if((db = ndbopen(nil)) == nil)
130 sysfatal("can't open ndb: %r");
131 tt = ndbipinfo(db, "sys", sysname, query, nelem(query));
132 for(t = tt; t; t = t->entry){
133 if(strcmp(t->attr, "ns") == 0)
135 else if(strcmp(t->attr, "dom") == 0)
137 else if(strcmp(t->attr, "dnsdomain") == 0)
139 else if(strcmp(t->attr, "inform") == 0)
149 sysfatal("no relevant ns=");
151 sysfatal("no relevant dom=");
153 sysfatal("no relevant dnsdomain=");
155 myipaddr(v6addr, net);
156 memmove(addr, v6addr + IPaddrlen - IPv4addrlen, IPv4addrlen);
159 print("ip=%V\n", addr);
160 print("ns=%s\n", ns);
161 print("dnsdomain=%s\n", dnsdomain);
162 print("dom=%s\n", dom);
165 if((fd = dial(netmkaddr(ns, "udp", "dns"), 0, 0, 0)) < 0)
166 sysfatal("can't dial %s: %r", ns);
168 txid = time(nil) + getpid();
171 p16(&p, txid); /* ID */
172 p16(&p, 5<<11); /* flags */
173 p16(&p, 1); /* # Zones */
174 p16(&p, 0); /* # prerequisites */
175 p16(&p, 2); /* # updates */
176 p16(&p, 0); /* # additionals */
178 pname(&p, dnsdomain); /* zone */
179 p16(&p, Tsoa); /* zone type */
180 p16(&p, Cin); /* zone class */
182 /* delete old name */
183 pname(&p, dom); /* name */
184 p16(&p, Ta); /* type: v4 addr */
185 p16(&p, Call); /* class */
186 p32(&p, 0); /* TTL */
187 p16(&p, 0); /* data len */
189 /* add new A record */
190 pname(&p, dom); /* name */
191 p16(&p, Ta); /* type: v4 addr */
192 p16(&p, Cin); /* class */
193 p32(&p, 60*60*25); /* TTL (25 hours) */
194 p16(&p, IPv4addrlen); /* data len */
195 pmem(&p, addr, IPv4addrlen); /* v4 address */
198 if(write(fd, buf, len) != len)
199 sysfatal("write failed: %r");
204 if(read(fd, buf, sizeof buf) < 0)
207 }while(g16(&p) != txid);
213 if(err != 0 && err != 7) /* err==7 is just a "yes, I know" warning */
214 if(err < nelem(errmsgs))
215 sysfatal("%s", errmsgs[err]);
217 sysfatal("unknown dns server error %d", err);