1 | /* |
1 | /* |
2 | vpn_dns.C -- handle the dns tunnel part of the protocol. |
2 | vpn_dns.C -- handle the dns tunnel part of the protocol. |
3 | Copyright (C) 2003-2004 Marc Lehmann <pcg@goof.com> |
3 | Copyright (C) 2003-2005 Marc Lehmann <gvpe@schmorp.de> |
4 | |
4 | |
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5 | This file is part of GVPE. |
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6 | |
5 | This program is free software; you can redistribute it and/or modify |
7 | GVPE is free software; you can redistribute it and/or modify |
6 | it under the terms of the GNU General Public License as published by |
8 | it under the terms of the GNU General Public License as published by |
7 | the Free Software Foundation; either version 2 of the License, or |
9 | the Free Software Foundation; either version 2 of the License, or |
8 | (at your option) any later version. |
10 | (at your option) any later version. |
9 | |
11 | |
10 | This program is distributed in the hope that it will be useful, |
12 | This program is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
13 | GNU General Public License for more details. |
15 | GNU General Public License for more details. |
14 | |
16 | |
15 | You should have received a copy of the GNU General Public License |
17 | You should have received a copy of the GNU General Public License |
16 | along with this program; if not, write to the Free Software |
18 | along with gvpe; if not, write to the Free Software |
17 | Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
19 | Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
18 | */ |
20 | */ |
19 | |
21 | |
20 | #include "config.h" |
22 | #include "config.h" |
21 | |
23 | |
… | |
… | |
35 | #include <unistd.h> |
37 | #include <unistd.h> |
36 | #include <fcntl.h> |
38 | #include <fcntl.h> |
37 | |
39 | |
38 | #include <map> |
40 | #include <map> |
39 | |
41 | |
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42 | #include <gmp.h> |
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43 | |
40 | #include "netcompat.h" |
44 | #include "netcompat.h" |
41 | |
45 | |
42 | #include "vpn.h" |
46 | #include "vpn.h" |
43 | |
47 | |
44 | #define MIN_RETRY 1. |
48 | #define MIN_RETRY 1. |
45 | #define MAX_RETRY 60. |
49 | #define MAX_RETRY 60. |
46 | |
50 | |
47 | #define MAX_OUTSTANDING 10 // max. outstanding requests |
51 | #define MAX_OUTSTANDING 400 // max. outstanding requests |
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52 | #define MAX_WINDOW 1000 // max. for MAX_OUTSTANDING |
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53 | #define MAX_RATE 10000 // requests/s |
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54 | #define MAX_BACKLOG (10*1024) // size of protocol backlog, must be > MAXSIZE |
48 | |
55 | |
49 | /* |
56 | #define MAX_DOMAIN_SIZE 220 // 255 is legal limit, but bind doesn't compress well |
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57 | // 240 leaves about 4 bytes of server reply data |
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58 | // every two request byte sless give room for one reply byte |
50 | |
59 | |
51 | protocol, in shorthand :) |
60 | // seqno has 12 bits (3 bytes a 4 bits in the header) |
52 | |
61 | #define SEQNO_MASK 0x7fff |
53 | client -> server <req> ANY? |
62 | #define SEQNO_EQ(a,b) ( 0 == ( ((a) ^ (b)) & SEQNO_MASK) ) |
54 | server -> client <req> TXT <rep> |
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55 | |
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56 | <req> is dns64-encoded <client-id:12><recv-seqno:10>[<send-seqno:10><data>] |
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57 | <rep> is dns64-encoded <0:12><recv-seqno:10>[<send-seqno:10><data>] |
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58 | |
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59 | if <client-id> is zero, the connection will be configured: |
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60 | |
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61 | <0:12><0:4>client-id:12><default-ttl:8><max-size:16><flags:16> |
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62 | |
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63 | */ |
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64 | |
63 | |
65 | #define MAX_LBL_SIZE 63 |
64 | #define MAX_LBL_SIZE 63 |
66 | #define MAX_PKT_SIZE 512 |
65 | #define MAX_PKT_SIZE 512 |
67 | |
66 | |
68 | #define RR_TYPE_TXT 16 |
67 | #define RR_TYPE_TXT 16 |
69 | #define RR_TYPE_ANY 255 |
68 | #define RR_TYPE_ANY 255 |
70 | #define RR_CLASS_IN 1 |
69 | #define RR_CLASS_IN 1 |
71 | |
70 | |
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71 | // works for cmaps up to 255 (not 256!) |
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72 | struct charmap |
|
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73 | { |
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74 | enum { INVALID = (u8)255 }; |
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75 | |
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76 | char encode [256]; // index => char |
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77 | u8 decode [256]; // char => index |
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78 | unsigned int size; |
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79 | |
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80 | charmap (const char *cmap); |
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81 | }; |
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82 | |
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83 | charmap::charmap (const char *cmap) |
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84 | { |
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85 | char *enc = encode; |
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86 | u8 *dec = decode; |
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87 | |
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88 | memset (enc, (char) 0, 256); |
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89 | memset (dec, (char)INVALID, 256); |
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90 | |
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91 | for (size = 0; cmap [size]; size++) |
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92 | { |
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93 | enc [size] = cmap [size]; |
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94 | dec [(u8)enc [size]] = size; |
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95 | } |
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96 | |
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97 | assert (size < 256); |
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98 | } |
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99 | |
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100 | #define MAX_DEC_LEN 500 |
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101 | #define MAX_ENC_LEN (MAX_DEC_LEN * 2) |
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102 | #define MAX_LIMBS ((MAX_DEC_LEN * 8 + GMP_NUMB_BITS - 1) / GMP_NUMB_BITS) |
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103 | |
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104 | // ugly. minimum base is 16(!) |
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105 | struct basecoder |
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106 | { |
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107 | charmap cmap; |
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108 | unsigned int enc_len [MAX_DEC_LEN]; |
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109 | unsigned int dec_len [MAX_ENC_LEN]; |
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110 | |
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111 | unsigned int encode_len (unsigned int len); |
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112 | unsigned int decode_len (unsigned int len); |
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113 | |
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114 | unsigned int encode (char *dst, u8 *src, unsigned int len); |
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115 | unsigned int decode (u8 *dst, char *src, unsigned int len); |
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116 | |
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117 | basecoder (const char *cmap); |
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118 | }; |
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119 | |
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120 | basecoder::basecoder (const char *cmap) |
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121 | : cmap (cmap) |
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122 | { |
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123 | for (unsigned int len = 0; len < MAX_DEC_LEN; ++len) |
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124 | { |
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125 | u8 src [MAX_DEC_LEN]; |
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126 | u8 dst [MAX_ENC_LEN]; |
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127 | |
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128 | memset (src, 255, len); |
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129 | |
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130 | mp_limb_t m [MAX_LIMBS]; |
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131 | mp_size_t n; |
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132 | |
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133 | n = mpn_set_str (m, src, len, 256); |
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134 | n = mpn_get_str (dst, this->cmap.size, m, n); |
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135 | |
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136 | for (int i = 0; !dst [i]; ++i) |
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137 | n--; |
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138 | |
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139 | enc_len [len] = n; |
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140 | dec_len [n] = len; |
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141 | } |
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142 | } |
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143 | |
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144 | unsigned int basecoder::encode_len (unsigned int len) |
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145 | { |
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146 | return enc_len [len]; |
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147 | } |
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148 | |
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149 | unsigned int basecoder::decode_len (unsigned int len) |
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150 | { |
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151 | while (len && !dec_len [len]) |
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152 | --len; |
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153 | |
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154 | return dec_len [len]; |
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155 | } |
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156 | |
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157 | unsigned int basecoder::encode (char *dst, u8 *src, unsigned int len) |
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158 | { |
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159 | if (!len) |
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160 | return 0; |
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161 | |
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162 | int elen = encode_len (len); |
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163 | |
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164 | mp_limb_t m [MAX_LIMBS]; |
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165 | mp_size_t n; |
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166 | |
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167 | u8 dst_ [MAX_ENC_LEN]; |
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168 | |
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169 | n = mpn_set_str (m, src, len, 256); |
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170 | n = mpn_get_str (dst_, cmap.size, m, n); |
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171 | |
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172 | int plen = elen; // for padding |
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173 | |
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174 | while (n < plen) |
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175 | { |
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176 | *dst++ = cmap.encode [0]; |
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177 | plen--; |
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178 | } |
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179 | |
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180 | for (unsigned int i = n - plen; i < n; ++i) |
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181 | *dst++ = cmap.encode [dst_ [i]]; |
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182 | |
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183 | return elen; |
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184 | } |
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185 | |
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186 | unsigned int basecoder::decode (u8 *dst, char *src, unsigned int len) |
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187 | { |
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188 | if (!len) |
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189 | return 0; |
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190 | |
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191 | u8 src_ [MAX_ENC_LEN]; |
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192 | unsigned int elen = 0; |
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193 | |
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194 | while (len--) |
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195 | { |
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196 | u8 val = cmap.decode [(u8)*src++]; |
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197 | |
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198 | if (val != charmap::INVALID) |
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199 | src_ [elen++] = val; |
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200 | } |
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201 | |
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202 | int dlen = decode_len (elen); |
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203 | |
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204 | mp_limb_t m [MAX_LIMBS]; |
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205 | mp_size_t n; |
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206 | |
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207 | u8 dst_ [MAX_DEC_LEN]; |
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208 | |
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209 | n = mpn_set_str (m, src_, elen, cmap.size); |
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210 | n = mpn_get_str (dst_, 256, m, n); |
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211 | |
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212 | if (n < dlen) |
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213 | { |
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214 | memset (dst, 0, dlen - n); |
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215 | memcpy (dst + dlen - n, dst_, n); |
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216 | } |
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217 | else |
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218 | memcpy (dst, dst_ + n - dlen, dlen); |
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219 | |
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220 | return dlen; |
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221 | } |
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222 | |
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223 | #if 0 |
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224 | struct test { test (); } test; |
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225 | |
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226 | test::test () |
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227 | { |
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228 | basecoder cdc ("0123456789abcdefghijklmnopqrstuvwxyz"); |
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229 | |
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230 | u8 in[] = "0123456789abcdefghijklmnopqrstuvwxyz"; |
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231 | static char enc[200]; |
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232 | static u8 dec[200]; |
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233 | |
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234 | for (int i = 1; i < 20; i++) |
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235 | { |
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236 | int elen = cdc.encode (enc, in, i); |
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237 | int dlen = cdc.decode (dec, enc, elen); |
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238 | |
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239 | printf ("%d>%d>%d (%s>%s)\n", i, elen, dlen, enc, dec); |
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240 | } |
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241 | abort (); |
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242 | } |
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243 | #endif |
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244 | |
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245 | // the following sequence has been crafted to |
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246 | // a) look somewhat random |
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247 | // b) the even (and odd) indices never share the same character as upper/lowercase |
72 | // the "_" is not valid but widely accepted (all octets should be supported, but let's be conservative) |
248 | // the "_" is not valid but widely accepted (all octets should be supported, but let's be conservative) |
73 | struct dns64 |
249 | // the other sequences are obviously derived |
74 | { |
250 | //static basecoder cdc63 ("_dDpPhHzZrR06QqMmjJkKBb34TtSsvVlL81xXaAeEFf92WwGgYyoO57UucCNniI"); |
75 | static const char encode_chars[64 + 1]; |
251 | static basecoder cdc62 ("dDpPhHzZrR06QqMmjJkKBb34TtSsvVlL81xXaAeEFf92WwGgYyoO57UucCNniI"); |
76 | static s8 decode_chars[256]; |
252 | //static basecoder cdc36 ("dphzr06qmjkb34tsvl81xaef92wgyo57ucni"); // unused as of yet |
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253 | static basecoder cdc26 ("dPhZrQmJkBtSvLxAeFwGyO"); |
77 | |
254 | |
78 | static int encode_len (int bytes) { return (bytes * 8 + 5) / 6; } |
255 | ///////////////////////////////////////////////////////////////////////////// |
79 | static int decode_len (int bytes) { return (bytes * 6) / 8; } |
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80 | static void encode (char *dst, u8 *src, int len); |
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81 | static void decode (u8 *dst, char *src, int len); |
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82 | |
256 | |
83 | dns64 (); |
257 | #define HDRSIZE 6 |
84 | } dns64; |
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85 | |
258 | |
86 | const char dns64::encode_chars[64 + 1] = "0123456789-abcdefghijklmnopqrstuvwxyz_ABCDEFGHIJKLMNOPQRSTUVWXYZ"; |
259 | inline void encode_header (char *data, int clientid, int seqno) |
87 | s8 dns64::decode_chars[256]; |
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88 | |
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89 | dns64::dns64 () |
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90 | { |
260 | { |
91 | for (int i = 0; i < 64; i++) |
261 | u8 hdr[3] = { clientid, seqno >> 8, seqno }; |
92 | decode_chars [encode_chars [i]] = i + 1; |
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93 | } |
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94 | |
262 | |
95 | void dns64::encode (char *dst, u8 *src, int len) |
263 | assert (clientid < 256); |
96 | { |
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97 | // slow, but easy to debug |
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98 | unsigned int accum, bits = 0; |
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99 | |
264 | |
100 | while (len--) |
265 | cdc26.encode (data, hdr, 3); |
101 | { |
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102 | accum <<= 8; |
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103 | accum |= *src++; |
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104 | bits += 8; |
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105 | |
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106 | while (bits >= 6) |
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107 | { |
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108 | *dst++ = encode_chars [(accum >> (bits - 6)) & 63]; |
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109 | bits -= 6; |
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110 | } |
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111 | } |
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112 | |
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113 | if (bits) |
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114 | *dst++ = encode_chars [(accum << (6 - bits)) & 63]; |
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115 | } |
266 | } |
116 | |
267 | |
117 | void dns64::decode (u8 *dst, char *src, int len) |
268 | inline void decode_header (char *data, int &clientid, int &seqno) |
118 | { |
269 | { |
119 | // slow, but easy to debug |
270 | u8 hdr[3]; |
120 | unsigned int accum, bits = 0; |
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121 | |
271 | |
122 | while (len--) |
272 | cdc26.decode (hdr, data, HDRSIZE); |
123 | { |
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124 | s8 chr = decode_chars [(u8)*src++]; |
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125 | |
273 | |
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274 | printf ("DEC %02x %02x %02x %02x\n", hdr[0], hdr[1], hdr[2], hdr[3]); |
126 | |
275 | |
127 | if (!chr) |
276 | clientid = hdr[0]; |
128 | break; |
277 | seqno = (hdr[1] << 8) | hdr[2]; |
|
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278 | } |
129 | |
279 | |
130 | accum <<= 6; |
280 | ///////////////////////////////////////////////////////////////////////////// |
131 | accum |= chr - 1; |
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132 | bits += 6; |
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133 | |
281 | |
134 | while (bits >= 8) |
282 | struct byte_stream |
135 | { |
283 | { |
136 | *dst++ = accum >> (bits - 8); |
284 | u8 *data; |
137 | bits -= 8; |
285 | int maxsize; |
138 | } |
286 | int fill; |
139 | } |
287 | |
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288 | byte_stream (int maxsize); |
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289 | ~byte_stream (); |
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290 | |
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291 | bool empty () { return !fill; } |
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292 | int size () { return fill; } |
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293 | |
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294 | bool put (u8 *data, unsigned int datalen); |
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295 | bool put (vpn_packet *pkt); |
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296 | vpn_packet *get (); |
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297 | |
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298 | u8 *begin () { return data; } |
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299 | void remove (int count); |
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300 | }; |
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301 | |
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302 | byte_stream::byte_stream (int maxsize) |
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303 | : maxsize (maxsize), fill (0) |
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304 | { |
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305 | data = new u8 [maxsize]; |
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306 | } |
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307 | |
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308 | byte_stream::~byte_stream () |
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309 | { |
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310 | delete data; |
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311 | } |
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312 | |
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313 | void byte_stream::remove (int count) |
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314 | { |
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315 | if (count > fill) |
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316 | abort (); |
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317 | |
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318 | memmove (data, data + count, fill -= count); |
|
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319 | } |
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320 | |
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321 | bool byte_stream::put (u8 *data, unsigned int datalen) |
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322 | { |
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323 | if (maxsize - fill < datalen) |
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324 | return false; |
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325 | |
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326 | memcpy (this->data + fill, data, datalen); fill += datalen; |
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327 | |
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328 | return true; |
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329 | } |
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330 | |
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331 | bool byte_stream::put (vpn_packet *pkt) |
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332 | { |
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333 | if (maxsize - fill < pkt->len + 2) |
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334 | return false; |
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335 | |
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336 | data [fill++] = pkt->len >> 8; |
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337 | data [fill++] = pkt->len; |
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338 | |
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339 | memcpy (data + fill, &((*pkt)[0]), pkt->len); fill += pkt->len; |
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340 | |
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341 | return true; |
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342 | } |
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343 | |
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344 | vpn_packet *byte_stream::get () |
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345 | { |
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346 | int len = (data [0] << 8) | data [1]; |
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347 | |
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348 | if (len > MAXSIZE && fill >= 2) |
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349 | abort (); // TODO handle this gracefully, connection reset |
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350 | |
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351 | if (fill < len + 2) |
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352 | return 0; |
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353 | |
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354 | vpn_packet *pkt = new vpn_packet; |
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355 | |
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356 | pkt->len = len; |
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357 | memcpy (&((*pkt)[0]), data + 2, len); |
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358 | remove (len + 2); |
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359 | |
|
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360 | return pkt; |
140 | } |
361 | } |
141 | |
362 | |
142 | ///////////////////////////////////////////////////////////////////////////// |
363 | ///////////////////////////////////////////////////////////////////////////// |
143 | |
364 | |
144 | #define FLAG_QUERY ( 0 << 15) |
365 | #define FLAG_QUERY ( 0 << 15) |
… | |
… | |
147 | #define FLAG_OP_QUERY ( 0 << 11) |
368 | #define FLAG_OP_QUERY ( 0 << 11) |
148 | #define FLAG_AA ( 1 << 10) |
369 | #define FLAG_AA ( 1 << 10) |
149 | #define FLAG_TC ( 1 << 9) |
370 | #define FLAG_TC ( 1 << 9) |
150 | #define FLAG_RD ( 1 << 8) |
371 | #define FLAG_RD ( 1 << 8) |
151 | #define FLAG_RA ( 1 << 7) |
372 | #define FLAG_RA ( 1 << 7) |
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373 | #define FLAG_AUTH ( 1 << 5) |
152 | #define FLAG_RCODE_MASK (15 << 0) |
374 | #define FLAG_RCODE_MASK (15 << 0) |
153 | #define FLAG_RCODE_OK ( 0 << 0) |
375 | #define FLAG_RCODE_OK ( 0 << 0) |
154 | #define FLAG_RCODE_FORMERR ( 1 << 0) |
376 | #define FLAG_RCODE_FORMERR ( 1 << 0) |
155 | #define FLAG_RCODE_SERVFAIL ( 2 << 0) |
377 | #define FLAG_RCODE_SERVFAIL ( 2 << 0) |
156 | #define FLAG_RCODE_NXDOMAIN ( 3 << 0) |
378 | #define FLAG_RCODE_NXDOMAIN ( 3 << 0) |
157 | #define FLAG_RCODE_REFUSED ( 5 << 0) |
379 | #define FLAG_RCODE_REFUSED ( 5 << 0) |
158 | |
380 | |
159 | #define DEFAULT_CLIENT_FLAGS (FLAG_QUERY | FLAG_OP_QUERY | FLAG_RD) |
381 | #define DEFAULT_CLIENT_FLAGS (FLAG_QUERY | FLAG_OP_QUERY | FLAG_RD) |
160 | #define DEFAULT_SERVER_FLAGS (FLAG_RESPONSE | FLAG_OP_QUERY | FLAG_AA | FLAG_RD) |
382 | #define DEFAULT_SERVER_FLAGS (FLAG_RESPONSE | FLAG_OP_QUERY | FLAG_AA | FLAG_RD | FLAG_RA) |
161 | |
383 | |
162 | struct dns_packet : net_packet |
384 | struct dns_packet : net_packet |
163 | { |
385 | { |
164 | u16 id; |
386 | u16 id; |
165 | u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4 |
387 | u16 flags; // QR:1 Opcode:4 AA:1 TC:1 RD:1 RA:1 Z:3 RCODE:4 |
… | |
… | |
209 | struct dns_req |
431 | struct dns_req |
210 | { |
432 | { |
211 | dns_packet *pkt; |
433 | dns_packet *pkt; |
212 | tstamp next; |
434 | tstamp next; |
213 | int retry; |
435 | int retry; |
|
|
436 | connection *conn; |
|
|
437 | int seqno; |
214 | |
438 | |
215 | dns_req (connection *c, vpn_packet *p, int &offs); |
439 | dns_req (connection *c); |
|
|
440 | void gen_stream_req (int seqno, byte_stream *stream); |
216 | }; |
441 | }; |
217 | |
442 | |
218 | struct dns_rep |
|
|
219 | { |
|
|
220 | }; |
|
|
221 | |
|
|
222 | static u16 dns_id; // TODO: should be per-vpn |
443 | static u16 dns_id = 12098; // TODO: should be per-vpn |
223 | |
444 | |
224 | dns_req::dns_req (connection *c, vpn_packet *p, int &offs) |
445 | static u16 next_id () |
|
|
446 | { |
|
|
447 | // the simplest lsfr with periodicity 65535 i could find |
|
|
448 | dns_id = (dns_id << 1) |
|
|
449 | | (((dns_id >> 1) |
|
|
450 | ^ (dns_id >> 2) |
|
|
451 | ^ (dns_id >> 4) |
|
|
452 | ^ (dns_id >> 15)) & 1); |
|
|
453 | |
|
|
454 | return dns_id; |
|
|
455 | } |
|
|
456 | |
|
|
457 | dns_req::dns_req (connection *c) |
|
|
458 | : conn (c) |
225 | { |
459 | { |
226 | next = 0; |
460 | next = 0; |
227 | retry = 0; |
461 | retry = 0; |
228 | |
462 | |
229 | pkt = new dns_packet; |
463 | pkt = new dns_packet; |
230 | |
464 | |
231 | pkt->id = dns_id++; |
465 | pkt->id = next_id (); |
|
|
466 | } |
|
|
467 | |
|
|
468 | void dns_req::gen_stream_req (int seqno, byte_stream *stream) |
|
|
469 | { |
|
|
470 | this->seqno = seqno; |
|
|
471 | |
232 | pkt->flags = DEFAULT_CLIENT_FLAGS; |
472 | pkt->flags = htons (DEFAULT_CLIENT_FLAGS); |
233 | pkt->qdcount = htons (1 * 0); |
473 | pkt->qdcount = htons (1); |
234 | pkt->ancount = 0; |
|
|
235 | pkt->nscount = 0; |
|
|
236 | pkt->arcount = 0; |
|
|
237 | |
474 | |
238 | offs += 10000; |
475 | int offs = 6*2; |
|
|
476 | int dlen = MAX_DOMAIN_SIZE - (strlen (THISNODE->domain) + 2); |
|
|
477 | // MAX_DOMAIN_SIZE is technically 255, but bind doesn't compress responses well, |
|
|
478 | // so we need to have space for 2*MAX_DOMAIN_SIZE + header + extra |
239 | |
479 | |
240 | c->dns_sndq.push_back (this); |
480 | char enc[256], *encp = enc; |
|
|
481 | encode_header (enc, THISNODE->id, seqno); |
|
|
482 | |
|
|
483 | int datalen = cdc62.decode_len (dlen - (dlen + MAX_LBL_SIZE - 1) / MAX_LBL_SIZE - HDRSIZE); |
|
|
484 | |
|
|
485 | if (datalen > stream->size ()) |
|
|
486 | datalen = stream->size (); |
|
|
487 | |
|
|
488 | int enclen = cdc62.encode (enc + HDRSIZE, stream->begin (), datalen) + HDRSIZE; |
|
|
489 | |
|
|
490 | printf ("cdc62.encode %d->%d:%02x %02x %02x %02x\n", datalen, enclen, |
|
|
491 | stream->begin ()[0], |
|
|
492 | stream->begin ()[1], |
|
|
493 | stream->begin ()[2], |
|
|
494 | stream->begin ()[3]); |
|
|
495 | |
|
|
496 | stream->remove (datalen); |
|
|
497 | |
|
|
498 | while (enclen) |
|
|
499 | { |
|
|
500 | int lbllen = enclen < MAX_LBL_SIZE ? enclen : MAX_LBL_SIZE; |
|
|
501 | |
|
|
502 | (*pkt)[offs++] = lbllen; |
|
|
503 | memcpy (pkt->at (offs), encp, lbllen); |
|
|
504 | |
|
|
505 | offs += lbllen; |
|
|
506 | encp += lbllen; |
|
|
507 | |
|
|
508 | enclen -= lbllen; |
|
|
509 | } |
|
|
510 | |
|
|
511 | const char *suffix = THISNODE->domain; |
|
|
512 | |
|
|
513 | // add tunnel domain |
|
|
514 | for (;;) |
|
|
515 | { |
|
|
516 | const char *end = strchr (suffix, '.'); |
|
|
517 | |
|
|
518 | if (!end) |
|
|
519 | end = suffix + strlen (suffix); |
|
|
520 | |
|
|
521 | int len = end - suffix; |
|
|
522 | |
|
|
523 | (*pkt)[offs++] = len; |
|
|
524 | memcpy (&((*pkt)[offs]), suffix, len); |
|
|
525 | offs += len; |
|
|
526 | |
|
|
527 | if (!*end) |
|
|
528 | break; |
|
|
529 | |
|
|
530 | suffix = end + 1; |
|
|
531 | } |
|
|
532 | |
|
|
533 | (*pkt)[offs++] = 0; |
|
|
534 | (*pkt)[offs++] = RR_TYPE_ANY >> 8; (*pkt)[offs++] = RR_TYPE_ANY; |
|
|
535 | (*pkt)[offs++] = RR_CLASS_IN >> 8; (*pkt)[offs++] = RR_CLASS_IN; |
|
|
536 | |
|
|
537 | pkt->len = offs; |
|
|
538 | } |
|
|
539 | |
|
|
540 | struct dns_rcv |
|
|
541 | { |
|
|
542 | int seqno; |
|
|
543 | dns_packet *pkt; // reply packet |
|
|
544 | u8 data [MAXSIZE]; // actually part of the reply packet... |
|
|
545 | int datalen; |
|
|
546 | |
|
|
547 | dns_rcv (int seqno, u8 *data, int datalen); |
|
|
548 | ~dns_rcv (); |
|
|
549 | }; |
|
|
550 | |
|
|
551 | dns_rcv::dns_rcv (int seqno, u8 *data, int datalen) |
|
|
552 | : seqno (seqno), pkt (new dns_packet), datalen (datalen) |
|
|
553 | { |
|
|
554 | memcpy (this->data, data, datalen); |
|
|
555 | } |
|
|
556 | |
|
|
557 | dns_rcv::~dns_rcv () |
|
|
558 | { |
|
|
559 | delete pkt; |
241 | } |
560 | } |
242 | |
561 | |
243 | ///////////////////////////////////////////////////////////////////////////// |
562 | ///////////////////////////////////////////////////////////////////////////// |
244 | |
563 | |
245 | struct dns_cfg |
564 | struct dns_cfg |
… | |
… | |
249 | u8 unused1; |
568 | u8 unused1; |
250 | u16 max_size; |
569 | u16 max_size; |
251 | u8 flags1, flags2; |
570 | u8 flags1, flags2; |
252 | }; |
571 | }; |
253 | |
572 | |
254 | // reply to client-poll |
573 | void connection::dnsv4_receive_rep (struct dns_rcv *r) |
255 | void dnsv4_poll (dns_packet *pkt, int &offs) |
|
|
256 | { |
574 | { |
257 | int dlen = MAX_PKT_SIZE - offs - 2; |
575 | dns_rcvpq.push_back (r); |
258 | |
576 | |
259 | (*pkt) [offs++] = 0; |
577 | printf ("%d got inketc %d (%02x %02x %02x %02x)\n", THISNODE->id, r->seqno |
260 | (*pkt) [offs++] = 5; |
578 | ,r->data[0] |
261 | memcpy (&((*pkt)[offs]), "\01H\02\xff\x00", 5); |
579 | ,r->data[1] |
262 | offs += 5; |
580 | ,r->data[2] |
|
|
581 | ,r->data[3] |
|
|
582 | ); |
|
|
583 | redo: |
263 | |
584 | |
264 | pkt->ancount = htons (1); |
585 | // find next packet |
|
|
586 | for (vector<dns_rcv *>::iterator i = dns_rcvpq.end (); i-- != dns_rcvpq.begin (); ) |
|
|
587 | if (SEQNO_EQ (dns_rcvseq, (*i)->seqno)) |
|
|
588 | { |
|
|
589 | // enter the packet into our input stream |
|
|
590 | r = *i; |
|
|
591 | |
|
|
592 | printf ("%d checking for older packet %d\n", THISNODE->id, dns_rcvseq); |
|
|
593 | // remove the oldest packet, look forward, as it's oldest first |
|
|
594 | for (vector<dns_rcv *>::iterator j = dns_rcvpq.begin (); j != dns_rcvpq.end (); ++j) |
|
|
595 | if (SEQNO_EQ ((*j)->seqno, dns_rcvseq - MAX_WINDOW)) |
|
|
596 | { |
|
|
597 | printf ("%d removing %d\n", THISNODE->id, (*j)->seqno); |
|
|
598 | delete *j; |
|
|
599 | dns_rcvpq.erase (j); |
|
|
600 | break; |
|
|
601 | } |
|
|
602 | |
|
|
603 | dns_rcvseq = (dns_rcvseq + 1) & SEQNO_MASK; |
|
|
604 | |
|
|
605 | if (!dns_snddq && !dns_rcvdq) |
|
|
606 | { |
|
|
607 | dns_rcvdq = new byte_stream (MAX_BACKLOG * 2); |
|
|
608 | dns_snddq = new byte_stream (MAX_BACKLOG); |
|
|
609 | |
|
|
610 | dns_si.set (::conf.dns_forw_host, ::conf.dns_forw_port, PROT_DNSv4); |
|
|
611 | } |
|
|
612 | |
|
|
613 | if (!dns_rcvdq->put (r->data, r->datalen)) |
|
|
614 | abort (); // MUST never overflow, can be caused by data corruption, TODO |
|
|
615 | |
|
|
616 | while (vpn_packet *pkt = dns_rcvdq->get ()) |
|
|
617 | { |
|
|
618 | sockinfo si; |
|
|
619 | si.host = 0; si.port = 0; si.prot = PROT_DNSv4; |
|
|
620 | |
|
|
621 | vpn->recv_vpn_packet (pkt, si); |
|
|
622 | } |
|
|
623 | |
|
|
624 | // check for further packets |
|
|
625 | goto redo; |
|
|
626 | } |
|
|
627 | } |
|
|
628 | |
|
|
629 | dns_packet * |
|
|
630 | vpn::dnsv4_server (dns_packet *pkt) |
|
|
631 | { |
|
|
632 | u16 flags = ntohs (pkt->flags); |
|
|
633 | |
|
|
634 | //memcpy (&((*rep)[0]), &((*pkt)[0]), pkt->len); |
|
|
635 | int offs = 6 * 2; // skip header |
|
|
636 | |
265 | pkt->flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_OK); |
637 | pkt->flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_FORMERR); |
266 | |
638 | |
267 | printf ("we have room for %d bytes\n", dlen); |
639 | if (!(flags & (FLAG_RESPONSE | FLAG_OP_MASK | FLAG_TC)) |
|
|
640 | && pkt->qdcount == htons (1)) |
|
|
641 | { |
|
|
642 | char qname[MAXSIZE]; |
|
|
643 | int qlen = pkt->decode_label ((char *)qname, MAXSIZE - offs, offs); |
|
|
644 | |
|
|
645 | u16 qtype = (*pkt) [offs++] << 8; qtype |= (*pkt) [offs++]; |
|
|
646 | u16 qclass = (*pkt) [offs++] << 8; qclass |= (*pkt) [offs++]; |
|
|
647 | |
|
|
648 | pkt->qdcount = htons (1); |
|
|
649 | pkt->ancount = 0; |
|
|
650 | pkt->nscount = 0; // should be self, as other nameservers reply like this |
|
|
651 | pkt->arcount = 0; // a record for self, as other nameservers reply like this |
|
|
652 | |
|
|
653 | pkt->flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_NXDOMAIN); |
|
|
654 | |
|
|
655 | int dlen = strlen (THISNODE->domain); |
|
|
656 | |
|
|
657 | if (qclass == RR_CLASS_IN |
|
|
658 | && (qtype == RR_TYPE_ANY || qtype == RR_TYPE_TXT) |
|
|
659 | && qlen > dlen + 1 + HDRSIZE |
|
|
660 | && !memcmp (qname + qlen - dlen - 1, THISNODE->domain, dlen)) |
|
|
661 | { |
|
|
662 | // correct class, domain: parse |
|
|
663 | int client, seqno; |
|
|
664 | decode_header (qname, client, seqno); |
|
|
665 | |
|
|
666 | u8 data[MAXSIZE]; |
|
|
667 | int datalen = cdc62.decode (data, qname + HDRSIZE, qlen - (dlen + 1 + HDRSIZE)); |
|
|
668 | |
|
|
669 | printf ("cdc62.decode %d(%d): %02x %02x %02x %02x\n", |
|
|
670 | qlen - (dlen + 1 + HDRSIZE), datalen |
|
|
671 | ,data[0] |
|
|
672 | ,data[1] |
|
|
673 | ,data[2] |
|
|
674 | ,data[3]); |
|
|
675 | |
|
|
676 | printf ("SRV got %d <%.*s>\n", seqno, qlen, qname + HDRSIZE);//D |
|
|
677 | printf ("SRV got %d <%.*s>\n", seqno, qlen - (dlen + 1 + HDRSIZE), qname + HDRSIZE);//D |
|
|
678 | |
|
|
679 | if (0 < client && client <= conns.size ()) |
|
|
680 | { |
|
|
681 | connection *c = conns [client - 1]; |
|
|
682 | |
|
|
683 | for (vector<dns_rcv *>::iterator i = c->dns_rcvpq.end (); i-- != c->dns_rcvpq.begin (); ) |
|
|
684 | if (SEQNO_EQ ((*i)->seqno, seqno)) |
|
|
685 | { |
|
|
686 | // already seen that request: simply reply with the cached reply |
|
|
687 | dns_rcv *r = *i; |
|
|
688 | |
|
|
689 | printf ("DUPLICATE %d\n", htons (r->pkt->id));//D |
|
|
690 | |
|
|
691 | memcpy (pkt->at (0), r->pkt->at (0), offs = r->pkt->len); |
|
|
692 | pkt->id = r->pkt->id; |
|
|
693 | goto duplicate_request; |
|
|
694 | } |
|
|
695 | |
|
|
696 | // new packet, queue |
|
|
697 | dns_rcv *rcv = new dns_rcv (seqno, data, datalen); |
|
|
698 | c->dnsv4_receive_rep (rcv); |
|
|
699 | |
|
|
700 | // now generate reply |
|
|
701 | pkt->ancount = htons (1); // one answer RR |
|
|
702 | pkt->flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_OK); |
|
|
703 | |
|
|
704 | (*pkt) [offs++] = 0xc0; |
|
|
705 | (*pkt) [offs++] = 6 * 2; // same as in query section |
|
|
706 | |
|
|
707 | (*pkt) [offs++] = RR_TYPE_TXT >> 8; (*pkt) [offs++] = RR_TYPE_TXT; |
|
|
708 | (*pkt) [offs++] = RR_CLASS_IN >> 8; (*pkt) [offs++] = RR_CLASS_IN; |
|
|
709 | |
|
|
710 | (*pkt) [offs++] = 0; (*pkt) [offs++] = 0; |
|
|
711 | (*pkt) [offs++] = 0; (*pkt) [offs++] = 0; // TTL |
|
|
712 | |
|
|
713 | int dlen = MAX_PKT_SIZE - offs - 2; |
|
|
714 | |
|
|
715 | // bind doesn't compress well, so reduce further by one label length |
|
|
716 | dlen -= qlen; |
|
|
717 | |
|
|
718 | int rdlen_offs = offs += 2; |
|
|
719 | |
|
|
720 | while (c->dns_snddq |
|
|
721 | && !c->dns_snddq->empty () |
|
|
722 | && dlen > 1) |
|
|
723 | { |
|
|
724 | int txtlen = dlen <= 255 ? dlen - 1 : 255; |
|
|
725 | |
|
|
726 | if (txtlen > c->dns_snddq->size ()) |
|
|
727 | txtlen = c->dns_snddq->size (); |
|
|
728 | |
|
|
729 | (*pkt)[offs++] = txtlen; |
|
|
730 | memcpy (pkt->at (offs), c->dns_snddq->begin (), txtlen); |
|
|
731 | offs += txtlen; |
|
|
732 | c->dns_snddq->remove (txtlen); |
|
|
733 | |
|
|
734 | dlen -= txtlen + 1; |
|
|
735 | } |
|
|
736 | |
|
|
737 | // avoid empty TXT rdata |
|
|
738 | if (offs == rdlen_offs) |
|
|
739 | (*pkt)[offs++] = 0; |
|
|
740 | |
|
|
741 | int rdlen = offs - rdlen_offs; |
|
|
742 | |
|
|
743 | (*pkt) [rdlen_offs - 2] = rdlen >> 8; |
|
|
744 | (*pkt) [rdlen_offs - 1] = rdlen; |
|
|
745 | |
|
|
746 | // now update dns_rcv copy |
|
|
747 | rcv->pkt->len = offs; |
|
|
748 | memcpy (rcv->pkt->at (0), pkt->at (0), offs); |
|
|
749 | |
|
|
750 | duplicate_request: ; |
|
|
751 | } |
|
|
752 | else |
|
|
753 | pkt->flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_FORMERR); |
|
|
754 | } |
|
|
755 | |
|
|
756 | pkt->len = offs; |
|
|
757 | } |
|
|
758 | |
|
|
759 | return pkt; |
|
|
760 | } |
|
|
761 | |
|
|
762 | void |
|
|
763 | vpn::dnsv4_client (dns_packet *pkt) |
|
|
764 | { |
|
|
765 | u16 flags = ntohs (pkt->flags); |
|
|
766 | int offs = 6 * 2; // skip header |
|
|
767 | |
|
|
768 | pkt->qdcount = ntohs (pkt->qdcount); |
|
|
769 | pkt->ancount = ntohs (pkt->ancount); |
|
|
770 | |
|
|
771 | // go through our request list and find the corresponding request |
|
|
772 | for (vector<dns_req *>::iterator i = dns_sndpq.begin (); |
|
|
773 | i != dns_sndpq.end (); |
|
|
774 | ++i) |
|
|
775 | if ((*i)->pkt->id == pkt->id) |
|
|
776 | { |
|
|
777 | connection *c = (*i)->conn; |
|
|
778 | int seqno = (*i)->seqno; |
|
|
779 | u8 data[MAXSIZE], *datap = data; |
|
|
780 | |
|
|
781 | delete *i; |
|
|
782 | dns_sndpq.erase (i); |
|
|
783 | |
|
|
784 | if (flags & (FLAG_RESPONSE | FLAG_OP_MASK | FLAG_TC)) |
|
|
785 | { |
|
|
786 | char qname[MAXSIZE]; |
|
|
787 | |
|
|
788 | while (pkt->qdcount-- && offs < MAXSIZE - 4) |
|
|
789 | { |
|
|
790 | int qlen = pkt->decode_label ((char *)qname, MAXSIZE - offs, offs); |
|
|
791 | offs += 4; // skip qtype, qclass |
|
|
792 | } |
|
|
793 | |
|
|
794 | while (pkt->ancount-- && offs < MAXSIZE - 10) |
|
|
795 | { |
|
|
796 | int qlen = //D |
|
|
797 | pkt->decode_label ((char *)qname, MAXSIZE - offs, offs); |
|
|
798 | |
|
|
799 | printf ("got reply to <%.*s>\n", qlen, qname);//D |
|
|
800 | |
|
|
801 | u16 qtype = (*pkt) [offs++] << 8; qtype |= (*pkt) [offs++]; |
|
|
802 | u16 qclass = (*pkt) [offs++] << 8; qclass |= (*pkt) [offs++]; |
|
|
803 | u32 ttl = (*pkt) [offs++] << 24; |
|
|
804 | ttl |= (*pkt) [offs++] << 16; |
|
|
805 | ttl |= (*pkt) [offs++] << 8; |
|
|
806 | ttl |= (*pkt) [offs++]; |
|
|
807 | |
|
|
808 | u16 rdlen = (*pkt) [offs++] << 8; rdlen |= (*pkt) [offs++]; |
|
|
809 | |
|
|
810 | if (rdlen <= MAXSIZE - offs) |
|
|
811 | { |
|
|
812 | // decode bytes, finally |
|
|
813 | |
|
|
814 | while (rdlen) |
|
|
815 | { |
|
|
816 | int txtlen = (*pkt) [offs++]; |
|
|
817 | |
|
|
818 | assert (txtlen + offs < MAXSIZE - 1); |
|
|
819 | |
|
|
820 | memcpy (datap, pkt->at (offs), txtlen); |
|
|
821 | datap += txtlen; offs += txtlen; |
|
|
822 | |
|
|
823 | rdlen -= txtlen + 1; |
|
|
824 | } |
|
|
825 | |
|
|
826 | } |
|
|
827 | |
|
|
828 | } |
|
|
829 | } |
|
|
830 | |
|
|
831 | // todo: pkt now used |
|
|
832 | c->dnsv4_receive_rep (new dns_rcv (seqno, data, datap - data)); |
|
|
833 | |
|
|
834 | break; |
|
|
835 | } |
|
|
836 | |
|
|
837 | delete pkt; |
268 | } |
838 | } |
269 | |
839 | |
270 | void |
840 | void |
271 | vpn::dnsv4_ev (io_watcher &w, short revents) |
841 | vpn::dnsv4_ev (io_watcher &w, short revents) |
272 | { |
842 | { |
… | |
… | |
274 | { |
844 | { |
275 | dns_packet *pkt = new dns_packet; |
845 | dns_packet *pkt = new dns_packet; |
276 | struct sockaddr_in sa; |
846 | struct sockaddr_in sa; |
277 | socklen_t sa_len = sizeof (sa); |
847 | socklen_t sa_len = sizeof (sa); |
278 | |
848 | |
279 | int len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
849 | pkt->len = recvfrom (w.fd, &((*pkt)[0]), MAXSIZE, 0, (sockaddr *)&sa, &sa_len); |
280 | pkt->len = len; |
|
|
281 | |
850 | |
282 | u16 flags = ntohs (pkt->flags); |
851 | if (pkt->len > 0) |
283 | |
|
|
284 | if (THISNODE->dns_port) |
|
|
285 | { |
852 | { |
286 | // server |
853 | if (pkt->flags & htons (FLAG_TC)) |
287 | pkt->flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_FORMERR); |
|
|
288 | |
|
|
289 | int offs = 6 * 2; // skip header |
|
|
290 | |
|
|
291 | if (!(flags & (FLAG_RESPONSE | FLAG_OP_MASK | FLAG_TC)) |
|
|
292 | && pkt->qdcount == htons (1)) |
|
|
293 | { |
854 | { |
294 | char qname[MAXSIZE]; |
855 | slog (L_WARN, _("DNS request/response truncated, check protocol settings.")); |
295 | int qlen = pkt->decode_label ((char *)qname, MAXSIZE, offs); |
856 | //TODO connection reset |
296 | |
|
|
297 | printf ("rcvd packet len %d, id%04x flags%04x q%04x a%04x n%04x a%04x <%s>\n", len, |
|
|
298 | pkt->id, flags, pkt->qdcount, pkt->ancount, pkt->nscount, pkt->arcount, qname);//D |
|
|
299 | |
|
|
300 | u16 qtype = (*pkt) [offs++] << 8; qtype |= (*pkt) [offs++]; |
|
|
301 | u16 qclass = (*pkt) [offs++] << 8; qclass |= (*pkt) [offs++]; |
|
|
302 | |
|
|
303 | pkt->qdcount = htons (1); |
|
|
304 | pkt->ancount = 0; |
|
|
305 | pkt->nscount = 0; // should be self, as other nameservers reply like this |
|
|
306 | pkt->arcount = 0; // a record for self, as other nameservers reply like this |
|
|
307 | |
|
|
308 | pkt->flags = htons (DEFAULT_SERVER_FLAGS | FLAG_RCODE_NXDOMAIN); |
|
|
309 | |
|
|
310 | int dlen = strlen (THISNODE->domain); |
|
|
311 | |
|
|
312 | if (qclass == RR_CLASS_IN |
|
|
313 | && (qtype == RR_TYPE_ANY || qtype == RR_TYPE_TXT) |
|
|
314 | && qlen > dlen + 1 |
|
|
315 | && !memcmp (qname + qlen - dlen - 1, THISNODE->domain, dlen)) |
|
|
316 | { |
|
|
317 | // correct class, now generate reply |
|
|
318 | pkt->ancount = htons (1); // one answer RR |
|
|
319 | |
|
|
320 | (*pkt) [offs++] = 0xc0; |
|
|
321 | (*pkt) [offs++] = 6 * 2; // same as in query section |
|
|
322 | |
|
|
323 | (*pkt) [offs++] = RR_TYPE_TXT >> 8; (*pkt) [offs++] = RR_TYPE_TXT; |
|
|
324 | (*pkt) [offs++] = RR_CLASS_IN >> 8; (*pkt) [offs++] = RR_CLASS_IN; |
|
|
325 | |
|
|
326 | (*pkt) [offs++] = 0; (*pkt) [offs++] = 0; |
|
|
327 | (*pkt) [offs++] = 0; (*pkt) [offs++] = 0; // TTL |
|
|
328 | |
|
|
329 | dnsv4_poll (pkt, offs); |
|
|
330 | printf ("correct class\n"); |
|
|
331 | } |
|
|
332 | } |
857 | } |
333 | |
858 | |
|
|
859 | if (THISNODE->dns_port) |
|
|
860 | { |
|
|
861 | pkt = dnsv4_server (pkt); |
334 | sendto (w.fd, &((*pkt)[0]), offs, 0, (sockaddr *)&sa, sa_len); |
862 | sendto (w.fd, &((*pkt)[0]), pkt->len, 0, (sockaddr *)&sa, sa_len); |
335 | } |
863 | } |
336 | else |
864 | else |
337 | { |
865 | dnsv4_client (pkt); |
338 | // client |
|
|
339 | } |
866 | } |
340 | } |
867 | } |
341 | } |
868 | } |
342 | |
869 | |
343 | bool |
870 | bool |
344 | connection::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
871 | connection::send_dnsv4_packet (vpn_packet *pkt, const sockinfo &si, int tos) |
345 | { |
872 | { |
346 | if (dns_sndq.size () >= MAX_OUTSTANDING) |
873 | // never initialized |
|
|
874 | if (!dns_snddq && !dns_rcvdq) |
|
|
875 | { |
|
|
876 | dns_rcvdq = new byte_stream (MAX_BACKLOG * 2); |
|
|
877 | dns_snddq = new byte_stream (MAX_BACKLOG); |
|
|
878 | |
|
|
879 | //dns_rcvseq = dns_sndseq = 0; |
|
|
880 | |
|
|
881 | dns_si.set (::conf.dns_forw_host, ::conf.dns_forw_port, PROT_DNSv4); |
|
|
882 | } |
|
|
883 | |
|
|
884 | if (!dns_snddq->put (pkt)) |
347 | return false; |
885 | return false; |
348 | |
886 | |
349 | // split vpn packet into dns packets, add to sndq |
887 | // start timer if neccessary |
350 | for (int offs = 0; offs < pkt->len; ) |
888 | if (!THISNODE->dns_port && !dnsv4_tw.active) |
351 | new dns_req (this, pkt, offs); |
|
|
352 | |
|
|
353 | // force transmit |
|
|
354 | dnsv4_cb (dnsv4_tw); |
889 | dnsv4_cb (dnsv4_tw); |
355 | |
890 | |
356 | return true; |
891 | return true; |
357 | } |
892 | } |
358 | |
893 | |
359 | void |
894 | void |
360 | connection::dnsv4_cb (time_watcher &w) |
895 | connection::dnsv4_cb (time_watcher &w) |
361 | { |
896 | { |
362 | // check for timeouts and (re)transmit |
897 | // check for timeouts and (re)transmit |
363 | tstamp next = NOW + 60; |
898 | tstamp next = NOW + 60; |
|
|
899 | dns_req *send = 0; |
364 | |
900 | |
365 | slog (L_NOISE, _("dnsv4, %d packets in send queue\n"), dns_sndq.size ()); |
|
|
366 | |
|
|
367 | if (dns_sndq.empty ()) |
|
|
368 | { |
|
|
369 | next = NOW + 1; |
|
|
370 | // push poll packet |
|
|
371 | } |
|
|
372 | |
|
|
373 | for (vector<dns_req *>::iterator i = dns_sndq.begin (); |
901 | for (vector<dns_req *>::iterator i = vpn->dns_sndpq.begin (); |
374 | i != dns_sndq.end (); |
902 | i != vpn->dns_sndpq.end (); |
375 | ++i) |
903 | ++i) |
376 | { |
904 | { |
377 | dns_req *r = *i; |
905 | dns_req *r = *i; |
378 | |
906 | |
379 | if (r->next <= NOW) |
907 | if (r->next <= NOW) |
380 | { |
908 | { |
381 | slog (L_NOISE, _("dnsv4, send req %d\n"), r->pkt->id); |
909 | if (!send) |
|
|
910 | { |
|
|
911 | send = r; |
|
|
912 | |
|
|
913 | if (r->retry)//D |
|
|
914 | printf ("req %d:%d, retry %d\n", r->seqno, r->pkt->id, r->retry); |
382 | r->retry++; |
915 | r->retry++; |
383 | r->next = NOW + r->retry; |
916 | r->next = NOW + r->retry; |
|
|
917 | } |
384 | } |
918 | } |
385 | |
919 | |
386 | if (r->next < next) |
920 | if (r->next < next) |
387 | next = r->next; |
921 | next = r->next; |
388 | } |
922 | } |
389 | |
923 | |
390 | printf ("%f next\n", next); |
924 | if (!send |
|
|
925 | && vpn->dns_sndpq.size () < MAX_OUTSTANDING) |
|
|
926 | { |
|
|
927 | send = new dns_req (this); |
|
|
928 | send->gen_stream_req (dns_sndseq, dns_snddq); |
|
|
929 | vpn->dns_sndpq.push_back (send); |
|
|
930 | |
|
|
931 | dns_sndseq = (dns_sndseq + 1) & SEQNO_MASK; |
|
|
932 | } |
|
|
933 | |
|
|
934 | tstamp min_next = NOW + (1. / (tstamp)MAX_RATE); |
|
|
935 | |
|
|
936 | if (send) |
|
|
937 | { |
|
|
938 | dns_packet *pkt = send->pkt; |
|
|
939 | |
|
|
940 | next = min_next; |
|
|
941 | |
|
|
942 | sendto (vpn->dnsv4_fd, &((*pkt)[0]), pkt->len, 0, dns_si.sav4 (), dns_si.salenv4 ()); |
|
|
943 | } |
|
|
944 | else if (next < min_next) |
|
|
945 | next = min_next; |
|
|
946 | |
391 | w.start (next); |
947 | w.start (next); |
392 | } |
948 | } |
393 | |
949 | |
394 | #endif |
950 | #endif |
395 | |
951 | |