diff --git a/build/Makefile.am b/build/Makefile.am index aa004388..c2667d5d 100644 --- a/build/Makefile.am +++ b/build/Makefile.am @@ -5,6 +5,7 @@ noinst_bindir = $(top_builddir)/build EXTRA_DIST= include ../toxcore/Makefile.inc +include ../toxdns/Makefile.inc include ../toxav/Makefile.inc include ../other/Makefile.inc include ../testing/Makefile.inc diff --git a/libtoxcore.pc.in b/libtoxcore.pc.in index e05e51cd..a91a1fb7 100644 --- a/libtoxcore.pc.in +++ b/libtoxcore.pc.in @@ -7,5 +7,5 @@ Name: libtoxcore Description: Tox protocol library Requires: Version: @PACKAGE_VERSION@ -Libs: @NACL_OBJECTS_PKGCONFIG@ -L${libdir} @NACL_LDFLAGS@ -ltoxcore @NACL_LIBS@ @LIBS@ @MATH_LDFLAGS@ +Libs: @NACL_OBJECTS_PKGCONFIG@ -L${libdir} @NACL_LDFLAGS@ -ltoxdns -ltoxcore @NACL_LIBS@ @LIBS@ @MATH_LDFLAGS@ Cflags: -I${includedir} diff --git a/toxdns/Makefile.inc b/toxdns/Makefile.inc new file mode 100644 index 00000000..1e66ab3f --- /dev/null +++ b/toxdns/Makefile.inc @@ -0,0 +1,28 @@ +lib_LTLIBRARIES += libtoxdns.la + +libtoxdns_la_include_HEADERS = \ + ../toxdns/toxdns.h + +libtoxdns_la_includedir = $(includedir)/tox + +libtoxdns_la_SOURCES = ../toxdns/toxdns.h \ + ../toxdns/toxdns.c + +libtoxdns_la_CFLAGS = -I$(top_srcdir) \ + -I$(top_srcdir)/toxcore \ + $(LIBSODIUM_CFLAGS) \ + $(NACL_CFLAGS) \ + $(PTHREAD_CFLAGS) + +libtoxdns_la_LDFLAGS = $(TOXCORE_LT_LDFLAGS) \ + $(EXTRA_LT_LDFLAGS) \ + $(LIBSODIUM_LDFLAGS) \ + $(NACL_LDFLAGS) \ + $(MATH_LDFLAGS) \ + $(RT_LIBS) \ + $(WINSOCK2_LIBS) + +libtoxdns_la_LIBADD = $(LIBSODIUM_LIBS) \ + $(NACL_OBJECTS) \ + $(NAC_LIBS) \ + $(PTHREAD_LIBS) diff --git a/toxdns/toxdns.c b/toxdns/toxdns.c new file mode 100644 index 00000000..20a4486c --- /dev/null +++ b/toxdns/toxdns.c @@ -0,0 +1,224 @@ +/* toxdns.c + * + * Tox secure username DNS toxid resolving functions. + * + * Copyright (C) 2013 Tox project All Rights Reserved. + * + * This file is part of Tox. + * + * Tox is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * Tox is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with Tox. If not, see . + * + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include "../toxcore/Messenger.h" + +static const char base32[32] = {"abcdefghijklmnopqrstuvwxyz012345"}; + +#define _encode(a, b, c) \ +{ \ +uint8_t i = 0; \ + while(i != c) { \ + *a++ = base32[((b[0] >> bits) | (b[1] << (8 - bits))) & 0x1F]; \ + bits += 5; \ + if(bits >= 8) { \ + bits -= 8; \ + b++; \ + i++; \ + } \ + } \ +} \ + +typedef struct { + uint8_t temp_pk[crypto_box_PUBLICKEYBYTES]; + uint8_t temp_sk[crypto_box_SECRETKEYBYTES]; + uint8_t server_public_key[crypto_box_PUBLICKEYBYTES]; + uint8_t shared_key[crypto_box_KEYBYTES]; + uint32_t nonce; + uint32_t nonce_start; +} DNS_Object; + +static void dns_new_temp_keys(DNS_Object *d) +{ + d->nonce = d->nonce_start = random_int(); + crypto_box_keypair(d->temp_pk, d->temp_sk); + encrypt_precompute(d->server_public_key, d->temp_sk, d->shared_key); +} + +/* Create a new tox_dns3 object for server with server_public_key. + * + * return Null on failure. + * return pointer object on success. + */ +void *tox_dns3_new(uint8_t *server_public_key) +{ + DNS_Object *d = malloc(sizeof(DNS_Object)); + + if (d == NULL) + return NULL; + + memcpy(d->server_public_key, server_public_key, crypto_box_PUBLICKEYBYTES); + dns_new_temp_keys(d); + return d; +} + +/* Destroy the tox dns3 object. + */ +void tox_dns3_kill(void *dns3_object) +{ + memset(dns3_object, 0, sizeof(DNS_Object)); + free(dns3_object); +} + +/* Generate a dns3 string of string_max_len used to query the dns server reffered to by to + * dns3_object for a tox id registered to user with name of name_len. + * + * This is what the string returned looks like: + * 4haaaaipr1o3mz0bxweox541airydbovqlbju51mb4p0ebxq.rlqdj4kkisbep2ks3fj2nvtmk4daduqiueabmexqva1jc + * + * returns length of string on sucess. + * returns -1 on failure. + */ +int tox_generate_dns3_string(void *dns3_object, uint8_t *string, uint16_t string_max_len, uint8_t *name, + uint8_t name_len) +{ +#define DOT_INTERVAL (6 * 5) + int base = (sizeof(uint32_t) + crypto_box_PUBLICKEYBYTES + name_len + crypto_box_MACBYTES); + int end_len = ((base * 8) / 5) + (base / DOT_INTERVAL) + !!(base % 5); + + if (end_len > string_max_len) + return -1; + + DNS_Object *d = dns3_object; + uint8_t buffer[1024]; + uint8_t nonce[crypto_box_NONCEBYTES] = {0}; + memcpy(nonce, &d->nonce, sizeof(uint32_t)); + memcpy(buffer, &d->nonce, sizeof(uint32_t)); + memcpy(buffer + sizeof(uint32_t), d->temp_pk, crypto_box_PUBLICKEYBYTES); + int len = encrypt_data_symmetric(d->shared_key, nonce, name, name_len, + buffer + sizeof(uint32_t) + crypto_box_PUBLICKEYBYTES); + + if (len == -1) + return -1; + + int total_len = len + sizeof(uint32_t) + crypto_box_PUBLICKEYBYTES; + uint8_t *buff = buffer, *old_str = string; + buffer[total_len] = 0; + uint8_t bits = 0; + int i; + + for (i = 0; i < (total_len / DOT_INTERVAL); ++i) { + _encode(string, buff, DOT_INTERVAL); + *string = '.'; + ++string; + } + + _encode(string, buff, total_len % DOT_INTERVAL); +#undef DOT_INTERVAL + ++d->nonce; + + if (d->nonce == d->nonce_start) { + dns_new_temp_keys(d); + } + + if (end_len != string - old_str) { + printf("tox_generate_dns3_string Fail\n"); + return -1; + } + + return string - old_str; +} + + +static int decode(uint8_t *dest, uint8_t *src) +{ + uint8_t *p = src, *op = dest, bits = 0; + *op = 0; + + while (*p) { + uint8_t ch = *p++; + + switch (ch) { + case 'A' ... 'Z': { + ch = ch - 'A'; + break; + } + + case 'a' ... 'z': { + ch = ch - 'a'; + break; + } + + case '0' ... '5': { + ch = ch - '0' + 26; + break; + } + + default: { + return - 1; + } + } + + *op |= (ch << bits); + bits += 5; + + if (bits >= 8) { + bits -= 8; + ++op; + *op = (ch >> (5 - bits)); + } + } + + return op - dest; +} + +/* Decode and decrypt the id_record returned of length id_record_len into + * tox_id (needs to be at least TOX_FRIEND_ADDRESS_SIZE). + * + * the id_record passed to this function should look somewhat like this: + * 4haaaa2vgcxuycbuctvauik3plsv3d3aadv4zfjfhi3thaizwxinelrvigchv0ah3qjcsx5qhmaksb2lv2hm5cwbtx0yp + * + * returns -1 on failure. + * returns 0 on success. + * + */ +int tox_decrypt_dns3_TXT(void *dns3_object, uint8_t *tox_id, uint8_t *id_record, uint32_t id_record_len) +{ + DNS_Object *d = dns3_object; + + if (id_record_len != 93) + return -1; + + /*if (id_record_len > 255 || id_record_len <= (sizeof(uint32_t) + crypto_box_MACBYTES)) + return -1;*/ + + uint8_t data[id_record_len]; + int length = decode(data, id_record); + + if (length == -1) + return -1; + + uint8_t nonce[crypto_box_NONCEBYTES] = {0}; + memcpy(nonce, data, sizeof(uint32_t)); + nonce[sizeof(uint32_t)] = 1; + int len = decrypt_data_symmetric(d->shared_key, nonce, data + sizeof(uint32_t), length - sizeof(uint32_t), tox_id); + + if (len != FRIEND_ADDRESS_SIZE) + return -1; + + return 0; +} \ No newline at end of file diff --git a/toxdns/toxdns.h b/toxdns/toxdns.h new file mode 100644 index 00000000..ac84af9c --- /dev/null +++ b/toxdns/toxdns.h @@ -0,0 +1,78 @@ +/* toxdns.h + * + * Tox secure username DNS toxid resolving functions. + * + * Copyright (C) 2013 Tox project All Rights Reserved. + * + * This file is part of Tox. + * + * Tox is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * Tox is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with Tox. If not, see . + * + */ + +#ifndef TOXDNS_H +#define TOXDNS_H + +#include + +/* How to use this api to make secure tox dns3 requests: + * + * 1. Get the public key of a server that supports tox dns3. + * 2. use tox_dns3_new() to create a new object to create DNS requests + * and handle responses for that server. + * 3. Use tox_generate_dns3_string() to generate a string based on the name we want to query. + * 4. take the string and use it for your DNS request like this: + * _4haaaaipr1o3mz0bxweox541airydbovqlbju51mb4p0ebxq.rlqdj4kkisbep2ks3fj2nvtmk4daduqiueabmexqva1jc_._tox.utox.org + * + * 5. The TXT in the DNS you recieve should look like this: + * v=tox3;id=4haaaa2vgcxuycbuctvauik3plsv3d3aadv4zfjfhi3thaizwxinelrvigchv0ah3qjcsx5qhmaksb2lv2hm5cwbtx0yp + * 6. Take the id string and use it with tox_decrypt_dns3_TXT() to get the Tox id returned by the DNS server. + */ + +/* Create a new tox_dns3 object for server with server_public_key of size TOX_CLIENT_ID_SIZE. + * + * return Null on failure. + * return pointer object on success. + */ +void *tox_dns3_new(uint8_t *server_public_key); + +/* Destroy the tox dns3 object. + */ +void tox_dns3_kill(void *dns3_object); + +/* Generate a dns3 string of string_max_len used to query the dns server reffered to by to + * dns3_object for a tox id registered to user with name of name_len. + * + * This is what the string returned looks like: + * 4haaaaipr1o3mz0bxweox541airydbovqlbju51mb4p0ebxq.rlqdj4kkisbep2ks3fj2nvtmk4daduqiueabmexqva1jc + * + * returns length of string on sucess. + * returns -1 on failure. + */ +int tox_generate_dns3_string(void *dns3_object, uint8_t *string, uint16_t string_max_len, uint8_t *name, + uint8_t name_len); + +/* Decode and decrypt the id_record returned of length id_record_len into + * tox_id (needs to be at least TOX_FRIEND_ADDRESS_SIZE). + * + * the id_record passed to this function should look somewhat like this: + * 4haaaa2vgcxuycbuctvauik3plsv3d3aadv4zfjfhi3thaizwxinelrvigchv0ah3qjcsx5qhmaksb2lv2hm5cwbtx0yp + * + * returns -1 on failure. + * returns 0 on success. + * + */ +int tox_decrypt_dns3_TXT(void *dns3_object, uint8_t *tox_id, uint8_t *id_record, uint32_t id_record_len); + +#endif