├── .gitignore ├── LICENSE ├── README.md └── main.go /.gitignore: -------------------------------------------------------------------------------- 1 | /tor-dns 2 | /Tor-DNS 3 | /build.sh 4 | /.project 5 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU AFFERO GENERAL PUBLIC LICENSE 2 | Version 3, 19 November 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU Affero General Public License is a free, copyleft license for 11 | software and other kinds of works, specifically designed to ensure 12 | cooperation with the community in the case of network server software. 13 | 14 | The licenses for most software and other practical works are designed 15 | to take away your freedom to share and change the works. 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It is safest 628 | to attach them to the start of each source file to most effectively 629 | state the exclusion of warranty; and each file should have at least 630 | the "copyright" line and a pointer to where the full notice is found. 631 | 632 | 633 | Copyright (C) 634 | 635 | This program is free software: you can redistribute it and/or modify 636 | it under the terms of the GNU Affero General Public License as published 637 | by the Free Software Foundation, either version 3 of the License, or 638 | (at your option) any later version. 639 | 640 | This program is distributed in the hope that it will be useful, 641 | but WITHOUT ANY WARRANTY; without even the implied warranty of 642 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 643 | GNU Affero General Public License for more details. 644 | 645 | You should have received a copy of the GNU Affero General Public License 646 | along with this program. If not, see . 647 | 648 | Also add information on how to contact you by electronic and paper mail. 649 | 650 | If your software can interact with users remotely through a computer 651 | network, you should also make sure that it provides a way for users to 652 | get its source. For example, if your program is a web application, its 653 | interface could display a "Source" link that leads users to an archive 654 | of the code. There are many ways you could offer source, and different 655 | solutions will be better for different programs; see section 13 for the 656 | specific requirements. 657 | 658 | You should also get your employer (if you work as a programmer) or school, 659 | if any, to sign a "copyright disclaimer" for the program, if necessary. 660 | For more information on this, and how to apply and follow the GNU AGPL, see 661 | . 662 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | 2 | Tor-DNS: Simple DNS server that uses a Tor SOCKS5 proxy to resolve names 3 | ======================================================================== 4 | 5 | (c) 2013-2019 Bernd Fix >Y< 6 | 7 | (c) 2017,2020 Michał Trojnara 8 | 9 | This program is free software: you can redistribute it and/or modify it 10 | under the terms of the GNU Affero General Public License as published 11 | by the Free Software Foundation, either version 3 of the License, or 12 | (at your option) any later version. 13 | 14 | This program is distributed in the hope that it will be useful, but 15 | WITHOUT ANY WARRANTY; without even the implied warranty of 16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 | Affero General Public License for more details. 18 | 19 | You should have received a copy of the GNU Affero General Public License 20 | along with this program. If not, see . 21 | 22 | Introduction 23 | ------------ 24 | 25 | **N.B.: The functionality provided by this little application is 26 | basically identical to what you get by setting the 27 | *"DNSPort [address:]port|auto [isolation flags]"* parameter in your 28 | Tor configuration file. So consider this as a hands-on experiment 29 | for Tor proxy communication in Go.** 30 | 31 | In case you run a torified application (using the torsocks or tsocks 32 | helper scripts) and the application in question still uses (domain) 33 | names to address computers on the internet, the resulting DNS queries 34 | can jeopardize your anonymity if an adversary can monitor your DNS 35 | queries to the nameservers. 36 | 37 | This little DNS server uses the built-in Tor SOCKS5 functionality to 38 | resolve names via the Tor network and therefore helps to ensure your 39 | anonymity in the above cases. 40 | 41 | Currently the DNS server can only handle very simple queries (like 42 | resolving a name or reverse lookup of an IP address), but it can't 43 | return other records than those of type "A" (IPv4 addresses), so no 44 | "MX", "AAAA", "SOA", "NS" or "TXT" queries are answered at all. 45 | This is due to the limitations within the Tor proxy; whenever it is 46 | extended, the Tor-DNS service will make use of that new query types. 47 | 48 | Prerequisites 49 | ------------- 50 | 51 | This application assumes you have installed Tor on your local computer 52 | and that the local Tor relay is up and running as a SOCKS5 proxy. 53 | 54 | A detailed help is available at . 55 | 56 | Install 57 | ------- 58 | 59 | This version ot Tor-DNS is designed for the Go1 release; see 60 | for more details. 61 | 62 | To build an executable for your platform, change into the source directory 63 | and type the following command: 64 | 65 | ```bash 66 | $ go build -o tor-dns 67 | ``` 68 | 69 | This builds the required executable. 70 | 71 | Usage 72 | ----- 73 | 74 | The program can be run using the following command: 75 | 76 | ```bash 77 | $ sudo ./tor-dns 78 | ``` 79 | 80 | Because the server is running on the privileged port 53 (domain) it requires 81 | root permissions to be run. 82 | 83 | The program accepts the following command line arguments: 84 | 85 | * `-v`: verbose output (default: off) 86 | * `-D`: debug output (default: off) 87 | * `-p`: UDP port to listen on for DNS requests (default: 53) 88 | * `-s`: SOCKSv5 proxy used to resolve names (default: ":9050") 89 | 90 | The `-s` option is a two part string seperated by the `+` character; the first 91 | part specifies the network (`tcp` or `unix`) to use for connecting to the Tor 92 | proxy, the second part specifies the address (format depending on the selected 93 | network). If the first part is missing, the network is assumed to be `tcp` 94 | (backwards compatibility). To access the Tor proxy via a Unix domain socket, 95 | you can for example specify: 96 | 97 | ```bash 98 | $ sudo ./tor-dns -s "unix+/tmp/tor-proxy.sock" 99 | ``` 100 | 101 | Things to consider 102 | ------------------ 103 | 104 | * Make sure you have stopped any other DNS service on your local machine 105 | before starting Tor-DNS. 106 | * Make sure that Tor-DNS is used to resolve local queries by modifying the 107 | **/etc/resolv.conf** file or whatever is appropriate on your platform. 108 | -------------------------------------------------------------------------------- /main.go: -------------------------------------------------------------------------------- 1 | /* 2 | * Run simple DNS service loop: 3 | * - listen for incoming UDP4 packets on localhosts port 53 (domain). 4 | * - parse request and filter for simple DNS resolve queries (one query 5 | * per request, one result per response) 6 | * - forward valid requests to the Tor SOCKS5 proxy running on 7 | * localhost:9050 (default). 8 | * - send the response from the Tor resolver back to the requesting 9 | * client. 10 | * 11 | * (c) 2013-2019 Bernd Fix >Y< 12 | * (c) 2017,2020 Michał Trojnara 13 | * 14 | * This program is free software: you can redistribute it and/or modify it 15 | * under the terms of the GNU Affero General Public License as published 16 | * by the Free Software Foundation, either version 3 of the License, or 17 | * (at your option) any later version. 18 | * 19 | * This program is distributed in the hope that it will be useful, but 20 | * WITHOUT ANY WARRANTY; without even the implied warranty of 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 22 | * Affero General Public License for more details. 23 | * 24 | * You should have received a copy of the GNU Affero General Public License 25 | * along with this program. If not, see . 26 | */ 27 | 28 | package main 29 | 30 | import ( 31 | "encoding/hex" 32 | "errors" 33 | "flag" 34 | "fmt" 35 | "log" 36 | "net" 37 | "strconv" 38 | "strings" 39 | "time" 40 | ) 41 | 42 | var ( 43 | flVerbose = flag.Bool("v", false, "verbose output") 44 | flDebug = flag.Bool("D", false, "debug output") 45 | flDnsPort = flag.String("p", ":53", "the UDP port to listen for DNS requests on") 46 | flSocksProxy = flag.String("s", ":9050", "the SOCKSv5 proxy to resolve names via") 47 | ) 48 | 49 | // Run a simple DNS service on port 53 (domain) at localhost. 50 | func main() { 51 | if err := run(); err != nil { 52 | log.Fatal(err) 53 | } 54 | } 55 | 56 | // returned errors mean to exit non-zero 57 | func run() error { 58 | flag.Parse() 59 | 60 | srv_addr, err := net.ResolveUDPAddr("udp", *flDnsPort) 61 | if err != nil { 62 | return fmt.Errorf("[Tor-DNS] Can't resolve service address: " + err.Error()) 63 | } 64 | 65 | conn, err := net.ListenUDP("udp", srv_addr) 66 | if err != nil { 67 | return fmt.Errorf("[Tor-DNS] Can't listen on service port: " + err.Error()) 68 | } 69 | defer conn.Close() 70 | 71 | c := make(chan packet) 72 | for i := 0; i < 5; i++ { 73 | go worker(conn, c) 74 | } 75 | 76 | for { 77 | buf := make([]byte, 2048) 78 | n, addr, err := conn.ReadFrom(buf) 79 | if err == nil { 80 | var pkt packet 81 | pkt.addr = addr 82 | pkt.buf = buf[:n] 83 | select { 84 | case c <- pkt: 85 | default: // The pool is busy 86 | go process(conn, c, pkt) 87 | } 88 | } 89 | } 90 | 91 | return nil 92 | } 93 | 94 | type packet struct { 95 | addr net.Addr 96 | buf []byte 97 | } 98 | 99 | /* 100 | * DNS request/response data structures: 101 | * This assumes that each query returns one (or none) result. 102 | * - query opcode (0 for QUERY, 1 for IQUERY) 103 | * - query parameters (name/addr, type and class for names) 104 | * - response values (name/addr) 105 | */ 106 | type query struct { 107 | pkt *packet 108 | id int 109 | opcode int 110 | name string 111 | addr net.IP 112 | typ int 113 | class int 114 | } 115 | 116 | type result struct { 117 | q *query 118 | valid bool 119 | typ int 120 | name string 121 | addr net.IP 122 | } 123 | 124 | func worker(dns_conn *net.UDPConn, c <-chan packet) { 125 | for { 126 | resolve(dns_conn, c) 127 | } 128 | } 129 | 130 | func process(dns_conn *net.UDPConn, c chan packet, pkt packet) { 131 | go resolve(dns_conn, c) 132 | c <- pkt 133 | } 134 | 135 | func resolve(dns_conn *net.UDPConn, c <-chan packet) { 136 | defer func() { // Gracefully recover from index out of range 137 | if r := recover(); r != nil { 138 | fmt.Println("[Tor-DNS] recovered:", r) 139 | } 140 | }() 141 | 142 | // split SOCKS address into parts; use first part as network specification 143 | // and second part as address. If only one part is given, the network 144 | // defaults to "tcp" (backwards compatibility) 145 | network := "tcp" 146 | addr := *flSocksProxy 147 | parts := strings.Split(addr, "+") 148 | if len(parts) > 1 { 149 | network = parts[0] 150 | addr = parts[1] 151 | } 152 | 153 | socks_conn, err := net.Dial(network, addr) 154 | if err != nil { 155 | fmt.Println("[Tor-DNS] failed to connect to Tor proxy server: " + err.Error()) 156 | time.Sleep(time.Second * 1) // Rate-limit connection attempts 157 | return 158 | } 159 | defer socks_conn.Close() 160 | 161 | q, ok := disassemble(<-c) 162 | if !ok { 163 | return 164 | } 165 | 166 | if r, err := answer(socks_conn, q); err == nil { 167 | dns_conn.WriteTo(assemble(r), q.pkt.addr) 168 | } else { 169 | fmt.Printf("[Tor-DNS] Can't answer query %x: %s\n", q.id, err.Error()) 170 | } 171 | } 172 | 173 | /* 174 | * Handle incoming DNS packet: 175 | * - Only handle requests with at least one query resource record and 176 | * empty response resource records; skip all other packets. 177 | */ 178 | func disassemble(pkt packet) (q query, ok bool) { 179 | var pos, id, flags int 180 | id, pos = getShort(pkt.buf, pos) 181 | flags, pos = getShort(pkt.buf, pos) 182 | opcode := (flags >> 11) & 0xF 183 | if opcode > 1 { 184 | if *flVerbose { 185 | fmt.Printf("[Tor-DNS] Request has unsupported Opcode: %d\n", opcode) 186 | } 187 | return 188 | } 189 | 190 | var qd_cnt, an_cnt, ns_cnt, ar_cnt int 191 | qd_cnt, pos = getShort(pkt.buf, pos) 192 | an_cnt, pos = getShort(pkt.buf, pos) 193 | ns_cnt, pos = getShort(pkt.buf, pos) 194 | ar_cnt, pos = getShort(pkt.buf, pos) 195 | 196 | if ar_cnt > 0 { 197 | if *flVerbose { 198 | fmt.Printf("[Query:%x] Request has %d Additional RRs, but that is not supported\n", id, ar_cnt) 199 | } 200 | } 201 | if an_cnt > 0 || ns_cnt > 0 || qd_cnt != 1 { 202 | if *flVerbose { 203 | fmt.Printf("[Tor-DNS] Request has invalid counts: (%d,%d,%d)\n", qd_cnt, an_cnt, ns_cnt) 204 | } 205 | return 206 | } 207 | 208 | q.pkt = &pkt 209 | q.id = id 210 | q.opcode = opcode 211 | name, num := read_name(pkt.buf[pos:]) 212 | q.name = name 213 | pos += num 214 | q.typ, pos = getShort(pkt.buf, pos) 215 | q.class, pos = getShort(pkt.buf, pos) 216 | ok = true 217 | return 218 | } 219 | 220 | /* 221 | * Assemble DNS response from list of Tor SOCKS responses. 222 | */ 223 | func assemble(r result) []byte { 224 | buf := make([]byte, 2048) 225 | flags := 0x8180 // QR|RD|RA 226 | num := 0 227 | if r.valid { 228 | num = 1 229 | } else { 230 | flags |= 3 // NXDOMAIN 231 | } 232 | 233 | // Header 234 | pos := setShort(buf, 0, r.q.id) // ID 235 | pos = setShort(buf, pos, flags) 236 | pos = setShort(buf, pos, 1) // QDCOUNT 237 | pos = setShort(buf, pos, num) // ANCOUNT 238 | pos = setShort(buf, pos, 0) // NSCOUNT 239 | pos = setShort(buf, pos, 0) // ARCOUNT 240 | 241 | // Question 242 | name_start := pos 243 | pos = write_name(buf, pos, r.q.name) // QNAME 244 | pos = setShort(buf, pos, r.q.typ) // QTYPE 245 | pos = setShort(buf, pos, r.q.class) // QCLASS 246 | 247 | // Answer 248 | if r.valid { 249 | pos = setShort(buf, pos, 0xC000|name_start) // NAME 250 | if r.typ == 1 { // SOCKS5 IP v4 address 251 | pos = setShort(buf, pos, 1) // TYPE := A 252 | } else if r.typ == 4 { // SOCKS5 IP v6 address 253 | pos = setShort(buf, pos, 28) // TYPE := AAAA 254 | } else { 255 | pos = setShort(buf, pos, r.q.typ) // TYPE := requested 256 | } 257 | pos = setShort(buf, pos, r.q.class) // CLASS 258 | pos = setShort(buf, pos, 0) // TTL high 259 | pos = setShort(buf, pos, 900) // TTL low (15 minutes) 260 | rdlength := pos 261 | pos += 2 // Fill RDLENGTH later 262 | idx := pos 263 | if r.typ == 1 || r.typ == 4 { // SOCKS5 IP address 264 | for i, v := range r.addr { 265 | buf[pos+i] = v 266 | } 267 | pos += 4 * r.typ 268 | } else { 269 | pos = write_name(buf, pos, r.name) 270 | } 271 | setShort(buf, rdlength, pos-idx) // RDLENGTH 272 | } 273 | 274 | if *flDebug { 275 | fmt.Println("!!! " + hex.EncodeToString(buf[:pos])) 276 | } 277 | return buf[:pos] 278 | } 279 | 280 | /* 281 | * Use the Tor SOCKS5 proxy to resolve names: 282 | * Simple approach - one query returns exactly one result (or none at all) 283 | * - normal queries (op=0) pass a name and (usually) request a ip-addr 284 | * (reverse queries can be name-based with names of the form 285 | * "a.b.c.d.in-addr.arpa"; this yields a name instead of an ip-addr) 286 | * - reverse queries (op=1) pass an ip-addr and request a name 287 | */ 288 | func answer(conn net.Conn, q query) (r result, err error) { 289 | buf := make([]byte, 128) 290 | r.q = &q 291 | r.valid = false 292 | 293 | buf[0] = 5 294 | buf[1] = 1 295 | buf[2] = 0 296 | n, err := conn.Write(buf[:3]) 297 | if n != 3 || err != nil { 298 | fmt.Println("[Tor-DNS] failed to write to Tor proxy server: " + err.Error()) 299 | return 300 | } 301 | n, err = conn.Read(buf) 302 | if n != 2 || err != nil { 303 | fmt.Println("[Tor-DNS] failed to read from Tor proxy server: " + err.Error()) 304 | return 305 | } 306 | if buf[0] != 5 || buf[1] == 0xFF { 307 | fmt.Println("[Tor-DNS] Tor proxy server refuses non-authenticated connection.") 308 | err = errors.New("Failed authentication") 309 | return 310 | } 311 | 312 | if *flVerbose { 313 | if q.opcode == 0 { 314 | fmt.Printf("[Query:%x:%d] %s\n", q.id, q.typ, q.name) 315 | } else { 316 | fmt.Printf("[Query:%x:%d] %s\n", q.id, q.typ, q.addr.String()) 317 | } 318 | } 319 | 320 | size := 0 321 | buf[0] = 5 // VER: 5 322 | if q.opcode == 0 { // QUERY 323 | var dn []byte 324 | if q.typ == 12 { // PTR 325 | buf[1] = 0xF1 // CMD: RESOLVE_PTR 326 | dn = []byte(ptr2ip(q.name)) 327 | } else { // Any other record type 328 | buf[1] = 0xF0 // CMD: RESOLVE 329 | dn = []byte(q.name) 330 | } 331 | num := len(dn) 332 | buf[2] = 0 // RSV 333 | buf[3] = 3 // ATYP: DOMAINNAME 334 | buf[4] = byte(num) 335 | for i, v := range dn { 336 | buf[5+i] = v 337 | } 338 | buf[5+num] = 0 // DST.PORT 339 | buf[6+num] = 0 // DST.PORT 340 | size = num + 7 341 | } else { // IQUERY (obsoleted by RFC 3425 in November 2002) 342 | buf[1] = 0xF1 // CMD: RESOLVE_PTR 343 | buf[2] = 0 // RSV 344 | if len(q.addr) != 4 { 345 | return 346 | } 347 | buf[3] = 1 // ATYP: IP V4 address 348 | for i, v := range q.addr { 349 | buf[4+i] = v 350 | } 351 | buf[8] = 0 // DST.PORT 352 | buf[9] = 0 // DST.PORT 353 | size = 10 354 | } 355 | 356 | if *flDebug { 357 | fmt.Println("<<< " + hex.EncodeToString(buf[:size])) 358 | } 359 | 360 | n, err = conn.Write(buf[:size]) 361 | if err != nil { 362 | fmt.Printf("[Tor-DNS] Tor proxy request failure for query %x: %s\n", q.id, err.Error()) 363 | return 364 | } 365 | if n != size { 366 | err = errors.New("Size mismtach") 367 | fmt.Printf("[Tor-DNS] Tor proxy request failure for query %x: %s\n", q.id, err.Error()) 368 | return 369 | } 370 | n, err = conn.Read(buf) 371 | if err != nil { 372 | fmt.Printf("[Tor-DNS] Tor proxy response failure for query %x: %s\n", q.id, err.Error()) 373 | return 374 | } 375 | if buf[1] != 0 { 376 | fmt.Printf("[Tor-DNS] Tor proxy response failure for query %x: %d\n", q.id, int(buf[1])&0xFF) 377 | return 378 | } 379 | 380 | if *flDebug { 381 | fmt.Println(">>> " + hex.EncodeToString(buf[:n])) 382 | } 383 | 384 | r.typ = int(buf[3]) & 0xFF 385 | if r.typ == 1 { // SOCKS5 IP v4 address 386 | r.addr = buf[4:8] 387 | if *flVerbose { 388 | fmt.Printf("[Response:%x] %s\n", q.id, r.addr.String()) 389 | } 390 | } else if r.typ == 3 { // SOCKS5 DOMAINNAME 391 | len := int(buf[4]) & 0xFF 392 | r.name = string(buf[5 : len+5]) 393 | if *flVerbose { 394 | fmt.Printf("[Response:%x] %s\n", q.id, r.name) 395 | } 396 | } else if r.typ == 4 { // SOCKS5 IP v6 address 397 | r.addr = buf[4:20] 398 | if *flVerbose { 399 | fmt.Printf("[Response:%x] %s\n", q.id, r.addr.String()) 400 | } 401 | } else { 402 | len := int(buf[4]) & 0xFF 403 | r.name = string(buf[5 : len+5]) 404 | if *flVerbose { 405 | fmt.Printf("[Response:%x:%d] %s\n", q.id, r.typ, hex.EncodeToString([]byte(r.name))) 406 | } 407 | } 408 | r.valid = true 409 | return 410 | } 411 | 412 | /* 413 | * Get an unsigned short value from two bytes at given position in an 414 | * array. Values are stored in network byte order (big endian). 415 | */ 416 | func getShort(buf []byte, pos int) (int, int) { 417 | val := (256 * (int(buf[pos]) & 0xFF)) + (int(buf[pos+1]) & 0xFF) 418 | return val, pos + 2 419 | } 420 | 421 | /* 422 | * Set an unsigned short value at a given position in a byte array. 423 | * Values are stored in network byte order (big endian). 424 | */ 425 | func setShort(buf []byte, pos, val int) int { 426 | buf[pos] = byte((val >> 8) & 0xFF) 427 | buf[pos+1] = byte(val & 0xFF) 428 | return pos + 2 429 | } 430 | 431 | /* 432 | * Read a name from a DNS resource record. Names can be stored in a 433 | * hierarchical structure where parts of the name are referenced 434 | * (part of a different name). 435 | */ 436 | func read_name(buf []byte) (string, int) { 437 | 438 | name := "" 439 | pos := 0 440 | len := int(buf[pos]) & 0xFF 441 | pos++ 442 | first := true 443 | for len > 0 { 444 | if first { 445 | first = false 446 | } else { 447 | name += "." 448 | } 449 | tag := len >> 6 450 | len &= 0x3F 451 | if tag == 0 { 452 | name += string(buf[pos : pos+len]) 453 | pos += len 454 | len = int(buf[pos]) & 0xFF 455 | pos++ 456 | } else if tag == 3 { 457 | ofs := 256*len + int(buf[pos])&0xFF 458 | subname, _ := read_name(buf[ofs:]) 459 | name += subname 460 | len = 0 461 | } 462 | } 463 | return name, pos 464 | } 465 | 466 | /* 467 | * Write name to DNS resource record (response). 468 | * Do not use funny optimization schemes like referencing sub-strings 469 | * within other names - just write a plain name in DNS convention. 470 | */ 471 | func write_name(buf []byte, pos int, name string) int { 472 | for len(name) > 0 { 473 | idx := strings.IndexRune(name, '.') 474 | if idx == -1 { 475 | idx = len(name) 476 | } 477 | buf[pos] = byte(idx) 478 | pos++ 479 | for i := 0; i < idx; i++ { 480 | buf[pos+i] = byte(name[i]) 481 | } 482 | pos += idx 483 | if idx == len(name) { 484 | break 485 | } 486 | name = string(name[idx+1:]) 487 | } 488 | buf[pos] = 0 489 | return pos + 1 490 | } 491 | 492 | func ptr2ip(name string) string { 493 | if strings.HasSuffix(name, ".in-addr.arpa") { 494 | var ip4 []byte 495 | for _, str := range strings.Split(name, ".")[:4] { 496 | num, _ := strconv.Atoi(str) 497 | ip4 = append([]byte{byte(num)}, ip4...) 498 | } 499 | return net.IP(ip4).String() 500 | } else if strings.HasSuffix(name, ".ip6.arpa") { 501 | var str string 502 | for _, chr := range strings.Split(name, ".")[:32] { 503 | str = chr + str 504 | } 505 | ip6 := make([]byte, hex.DecodedLen(len(str))) 506 | hex.Decode(ip6, []byte(str)) 507 | return net.IP(ip6).String() 508 | } else { 509 | return name // Nothing we could parse 510 | } 511 | } 512 | --------------------------------------------------------------------------------