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1 .\" Copyright (c) 2008 by Rhyolite Software, LLC |
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2 .\" |
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3 .\" This agreement is not applicable to any entity which sells anti-spam |
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4 .\" solutions to others or provides an anti-spam solution as part of a |
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5 .\" security solution sold to other entities, or to a private network |
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6 .\" which employs the DCC or uses data provided by operation of the DCC |
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7 .\" but does not provide corresponding data to other users. |
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8 .\" |
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9 .\" Permission to use, copy, modify, and distribute this software without |
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10 .\" changes for any purpose with or without fee is hereby granted, provided |
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11 .\" that the above copyright notice and this permission notice appear in all |
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12 .\" copies and any distributed versions or copies are either unchanged |
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13 .\" or not called anything similar to "DCC" or "Distributed Checksum |
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14 .\" Clearinghouse". |
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15 .\" |
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16 .\" Parties not eligible to receive a license under this agreement can |
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17 .\" obtain a commercial license to use DCC by contacting Rhyolite Software |
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18 .\" at sales@rhyolite.com. |
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19 .\" |
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20 .\" A commercial license would be for Distributed Checksum and Reputation |
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21 .\" Clearinghouse software. That software includes additional features. This |
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22 .\" free license for Distributed ChecksumClearinghouse Software does not in any |
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23 .\" way grant permision to use Distributed Checksum and Reputation Clearinghouse |
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24 .\" software |
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25 .\" |
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26 .\" THE SOFTWARE IS PROVIDED "AS IS" AND RHYOLITE SOFTWARE, LLC DISCLAIMS ALL |
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27 .\" WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES |
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28 .\" OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL RHYOLITE SOFTWARE, LLC |
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29 .\" BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES |
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30 .\" OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, |
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31 .\" WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, |
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32 .\" ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS |
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33 .\" SOFTWARE. |
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34 .\" |
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35 .\" Rhyolite Software DCC 1.3.103-1.143 $Revision$ |
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36 .\" |
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37 .Dd February 26, 2009 |
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38 .ds volume-ds-DCC Distributed Checksum Clearinghouse |
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39 .Dt dccd 8 DCC |
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40 .Os " " |
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41 .Sh NAME |
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42 .Nm dccd |
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43 .Nd Distributed Checksum Clearinghouse Daemon |
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44 .Sh SYNOPSIS |
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45 .Bk -words |
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46 .Nm dccd |
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47 .Op Fl 64dVbfFQ |
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48 .Fl i Ar server-ID |
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49 .Op Fl n Ar brand |
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50 .Op Fl h Ar homedir |
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51 .Fl I Xo |
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52 .Sm off |
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53 .Op Ar host-ID |
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54 .Op Ar ,user |
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55 .Sm on |
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56 .Xc |
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57 .br |
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58 .Oo |
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59 .Fl a Xo |
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60 .Sm off |
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61 .Op Ar server-addr |
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62 .Op Ar ,server-port |
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63 .Xc |
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64 .Sm on |
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65 .Oc |
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66 .Op Fl q Ar qsize |
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67 .br |
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68 .Oo |
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69 .Fl G Xo |
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70 .Sm off |
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71 .Op Ar on, |
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72 .Op Ar weak-body, |
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73 .Op Ar weak-IP, |
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74 .Op Ar embargo |
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75 .Op Ar ,window |
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76 .Op Ar ,white |
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77 .Xc |
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78 .Sm on |
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79 .Oc |
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80 .br |
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81 .Oo |
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82 .Fl W Xo |
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83 .Sm off |
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84 .Op Ar rate |
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85 .Op Ar ,chg |
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86 .Op Ar ,dbsize |
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87 .Sm on |
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88 .Xc |
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89 .Oc |
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90 .Oo |
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91 .Fl K Xo |
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92 .Sm off |
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93 .Op Ar no- |
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94 .Ar type |
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95 .Sm on |
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96 .Xc |
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97 .Oc |
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98 .Op Fl T Ar tracemode |
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99 .Op Fl u Ar anon-delay Ns Op Ar *inflate |
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100 .Op Fl C Ar dbclean |
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101 .Op Fl L Ar ltype,facility.level |
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102 .br |
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103 .Oo |
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104 .Fl R Xo |
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105 .Sm off |
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106 .Op Ar RL_SUB , |
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107 .Op Ar RL_ANON , |
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108 .Op Ar RL_ALL_ANON , |
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109 .Op Ar RL_BUGS |
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110 .Xc |
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111 .Sm on |
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112 .Oc |
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113 .Ek |
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114 .Sh DESCRIPTION |
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115 .Nm Dccd |
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116 receives reports of checksums related to mail received by DCC clients |
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117 and queries about the total number of reports of particular checksums. |
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118 A DCC server never receives |
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119 mail, address, headers, or other information from clients, but only |
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120 cryptographically secure checksums of such information. |
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121 A DCC server cannot determine the text or other information that corresponds |
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122 to the checksums it receives. |
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123 It only acts as a clearinghouse of total counts of checksums |
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124 computed by clients. |
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125 .Pp |
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126 Each DCC server or close cluster of DCC servers is identified by a numeric |
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127 .Ar server-ID . |
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128 Each DCC client is identified by a |
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129 .Ar client-ID , |
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130 either explicitly listed in the |
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131 .Pa ids |
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132 file or |
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133 the special anonymous client-ID. |
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134 Many computers are expected to share a single |
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135 .Ar client-ID . |
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136 A |
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137 .Ar server-ID |
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138 is less than 32768 while a |
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139 .Ar client-ID |
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140 is between 32768 and 16777215. |
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141 DCC server-IDs need be known only to DCC servers and the people running |
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142 them. |
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143 The passwords associated with DCC server-IDs should be protected, |
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144 because DCC servers listen to commands authenticated with server-IDs |
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145 and their associated passwords. |
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146 Each client that does not use the anonymous ID must know the client-ID |
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147 and password used by each of its servers. |
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148 A single client computer can use different passwords with different |
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149 server computers. |
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150 See the |
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151 .Pa ids |
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152 file. |
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153 .Pp |
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154 A whitelist of known good (or bad) sources of email prevents |
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155 legitimate mailing lists from being seen as unsolicited bulk email |
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156 by DCC clients. |
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157 The whitelist used by a DCC server is built into |
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158 the database when old entries are removed by |
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159 .Xr dbclean 8 . |
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160 Each DCC client has its own, local whitelist, and in general, |
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161 whitelists work better in DCC clients than servers. |
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162 .Pp |
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163 The effectiveness of a Distributed Checksum Clearinghouse |
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164 increases as the number of subscribers increases. |
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165 Flooding reports of checksums among DCC servers increases |
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166 the effective number of subscribers to each server. |
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167 Each |
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168 .Nm |
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169 daemon tries to maintain TCP/IP connections to the other servers |
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170 listed in the |
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171 .Pa flod |
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172 file, and send them reports containing checksums with total |
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173 counts exceeding thresholds. |
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174 Changes in the |
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175 .Pa flod |
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176 file are noticed automatically within minutes. |
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177 .Pp |
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178 Controls on report flooding are specified in the |
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179 .Pa flod |
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180 file. |
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181 Each line specifies a hostname and port number to which reports |
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182 should be flooded, |
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183 a server-ID to identify and authenticate the output stream, |
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184 a server-ID to identify and authenticate an input stream from the |
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185 same server, |
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186 and flags with each ID. |
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187 The ability to delete reports of checksums is handy, but could |
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188 be abused. |
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189 If |
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190 .Ar del |
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191 is not present among the |
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192 .Ar in-opts |
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193 options for the incoming ID, |
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194 incoming delete requests are logged and then ignored. |
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195 Floods from DCC "brands" that count only mail to |
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196 spam traps and whose servers use the |
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197 .Fl Q |
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198 option to count extremely bulk mail |
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199 should be marked with |
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200 .Ar traps . |
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201 They can be seen as counting millions of targets, so the |
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202 .Ar traps |
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203 flag on their |
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204 .Pa flod |
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205 file entry changes their incoming flooded reports counts to |
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206 .Em many. |
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207 .Pp |
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208 .Nm Dccd |
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209 automatically checks its |
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210 .Pa flod |
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211 and |
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212 .Pa ids |
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213 files periodically. |
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214 .Xr Cdcc 8 |
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215 has the commands |
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216 .Ic new ids |
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217 and |
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218 .Ic flood check |
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219 to tell |
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220 .Nm |
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221 to check those two files immediately. |
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222 Both files are also checked for changes after the SIGHUP signal. |
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223 .Ss OPTIONS |
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224 The following options are available: |
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225 .Bl -tag -width 3n |
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226 .It Fl 6 |
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227 enable IPv6. |
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228 The default is equivalent to |
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229 .Fl 4 . |
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230 See also the IPv4 and IPv6 options in the |
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231 .Pa flod |
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232 file description below and the |
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233 .Em IPv6 on |
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234 .Xr cdcc 8 |
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235 command. |
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236 .It Fl 4 |
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237 disable IPv6. |
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238 See also |
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239 .Fl 6 . |
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240 .It Fl d |
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241 enables debugging output. |
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242 Additional |
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243 .Fl d |
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244 options increase the number of messages. |
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245 .It Fl V |
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246 displays the version of the DCC server daemon. |
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247 .It Fl b |
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248 causes the server to not detach itself from the controlling tty |
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249 or put itself into the background. |
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250 .It Fl F |
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251 uses write() instead of mmap() in some cases to modify the DCC database. |
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252 It is the default on Solaris. |
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253 .It Fl f |
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254 turns off |
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255 .Fl F . |
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256 .It Fl Q |
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257 causes the server to treat reports of checksums as queries |
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258 except from DCC clients marked trusted in the |
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259 .Pa ids |
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260 file with |
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261 .Ar rpt-ok . |
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262 See |
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263 .Fl u |
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264 to turn off access by anonymous or unauthenticated clients |
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265 .It Fl i Ar server-ID |
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266 specifies the ID of this DCC server. |
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267 Each server identifies itself as responsible for checksums |
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268 that it forwards to other servers. |
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269 .It Fl n Ar brand |
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270 is an arbitrary string of letters and numbers that |
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271 identifies the organization running the DCC server. |
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272 The brand is required, and appears in the SMTP |
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273 .Em X-DCC |
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274 headers generated by the DCC. |
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275 .It Fl h Ar homedir |
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276 overrides the default DCC home directory, |
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277 .Pa @prefix@ . |
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278 .It Fl I Xo |
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279 .Sm off |
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280 .Op Ar host-ID |
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281 .Op Ar ,user |
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282 .Sm on |
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283 .Xc |
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284 changes the server's globally unique identity for flooding |
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285 from the default value |
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286 consisting of the first 16 characters of the host name. |
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287 or changes the UID and GID of the process |
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288 .Ar Host-ID |
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289 is a string of up to 16 characters that replaces the first |
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290 16 characters of the system's hostname in assertions |
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291 of the server-ID that are flooded to peers. |
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292 .Ar User |
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293 must be valid user name. |
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294 .It Fl a Xo |
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295 .Sm off |
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296 .Op Ar server-addr |
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297 .Op Ar ,server-port |
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298 .Sm on |
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299 .Xc |
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300 adds an hostname or IP address to the list of local IP addresses |
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301 that the server answers. |
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302 Multiple |
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303 .Fl a |
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304 options can be used to specify a subset of the available network |
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305 interfaces or to use more than one port number. |
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306 The default without any |
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307 .Fl a |
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308 options is to listen on all local IP addresses. |
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309 It can be useful to list some of the IP addresses of |
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310 multi-homed hosts to deal with firewalls. |
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311 By default |
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312 .Ar server-port |
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313 is 6277 for DCC servers and 6276 for Greylist servers. |
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314 It is the UDP port at which DCC |
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315 requests are received and the TCP port for incoming floods of reports. |
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316 .Pp |
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317 If |
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318 .Ar server-addr |
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319 is absent |
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320 and if the |
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321 .Xr getifaddrs 8 |
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322 function is supported, |
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323 separate UDP sockets are bound to each configured network interface so |
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324 that each DCC clients receives replies from the |
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325 IP addresses to which corresponding request are sent. |
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326 If |
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327 .Nm |
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328 is started before all network interfaces are turned on or |
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329 there are interfaces that are turned on and off or change their addresses |
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330 such as PPP interfaces, |
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331 then the special string |
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332 .Ar @ |
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333 should be used to tell |
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334 .Nm |
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335 to bind to an IN_ADDRANY UDP socket. |
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336 .Pp |
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337 Outgoing TCP connections to flood checksum reports to other DCC servers |
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338 used the IP address of a single |
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339 .Fl a |
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340 option, |
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341 but only if there is single option that is not localhost. |
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342 See also the |
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343 .Pa flod |
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344 file. |
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345 .It Fl q Ar qsize |
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346 specifies the maximum size of the queue of requests from anonymous or |
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347 unauthenticated clients. |
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348 The default value is the maximum DCC RTT in seconds times 200 or 1000. |
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349 .It Fl G Xo |
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350 .Sm off |
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351 .Op Ar on, |
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352 .Op Ar weak-body, |
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353 .Op Ar weak-IP, |
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354 .Op Ar embargo |
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355 .Op Ar ,window |
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356 .Op Ar ,white |
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357 .Xc |
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358 .Sm on |
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359 changes |
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360 .Nm |
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361 to a Greylist server for |
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362 .Xr dccm 8 |
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363 or |
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364 .Xr dccifd 8 . |
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365 Greylisting consists of temporarily rejecting or embargoing mail from |
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366 unfamiliar combinations of SMTP client IP address, SMTP envelope sender, |
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367 and SMTP envelope recipient. |
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368 If the SMTP client persists for |
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369 .Ar embargo seconds |
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370 and so is probably not an open proxy, worm-infected personal computer, |
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371 or other transient source of spam, the triple of |
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372 .Em (IP\ address,sender,recipient) |
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373 is added to a database similar to the usual DCC database. |
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374 If the SMTP client does not try again after |
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375 .Ar embargo |
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376 seconds and before |
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377 .Ar window |
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378 seconds after the first attempt, |
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379 the triple is forgotten. |
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380 If the SMTP client persists past the embargo, |
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381 the triple is added to the database and becomes familiar |
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382 and the message is accepted. |
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383 Familiar triples are remembered for |
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384 .Ar white |
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385 seconds after the last accepted mail message. |
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386 The triple is forgotten if it is ever associated with unsolicited bulk email. |
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387 .Pp |
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388 All three durations can be a number of minutes, hours, days, or |
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389 weeks followed by |
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390 .Ar MINUTES , |
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391 .Ar M , |
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392 .Ar HOURS , |
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393 .Ar H , |
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394 .Ar DAYS , |
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395 .Ar D , |
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396 .Ar WEEKS |
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397 or |
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398 .Ar W . |
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399 The default is |
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400 .Fl G Ar 270seconds,7days,63days . |
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401 The first duration or the |
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402 .Ar embargo |
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403 should be longer than open proxies can linger retransmitting. |
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404 The second |
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405 .Ar window |
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406 time should be as long as legitimate mail servers persist in retransmitting |
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407 to recognize embargoed messages whose retransmissions were not |
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408 received because of network or other problems. |
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409 The |
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410 .Ar white |
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411 time should be long enough to recognize and not embargo messages from |
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412 regular senders. |
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413 .Pp |
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414 Usually the DCC greylist system requires that an almost |
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415 identical copy of the message be retransmitted during the |
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416 .Ar embargo . |
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417 If |
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418 .Ar weak-body |
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419 is present, |
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420 any message with the same triple of sender IP address, sender mail |
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421 address, and target mail address ends the embargo, |
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422 even if the body of the message differs. |
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423 .Pp |
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424 If |
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425 .Ar weak-IP |
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426 is present, |
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427 all mail from an SMTP client at an IP address is accept |
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428 after any message from the same IP address has been accepted. |
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429 .Pp |
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430 Unlike DCC checksums, the contents of |
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431 greylist databases are private and do not benefit from broad sharing. |
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432 However, large installations can use more two or more greylist servers |
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433 flooding triples among themselves. |
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434 Flooding among greylist servers is controlled by the |
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435 .Pa grey_flod |
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436 file. |
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437 .Pp |
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438 All greylist cooperating or flooding greylist servers |
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439 .Em must |
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440 use the same |
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441 .Fl G |
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442 values. |
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443 .Pp |
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444 Clients of greylist servers cannot be anonymous and must have |
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445 client-IDs and passwords assigned in the |
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446 .Pa ids |
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447 file. |
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448 This implies that |
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449 .Xr cdcc |
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450 commands directed to greylist servers must specify the server-ID. |
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451 .Pp |
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452 White- and blacklists are honored by the DCC clients. |
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453 whitelisted messages are embargoed or checked with a greylist server. |
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454 The greylist triples of blacklisted messages, messages whose DCC counts make |
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455 them spam, and other messages known to be spam are sent to a greylist |
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456 server to be removed from the greylist database and cause an embargo |
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457 on the next messages with those triples. |
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458 .Pp |
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459 Messages whose checksums match greylist server whitelists |
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460 are not embargoed and the checksums of their triples are not |
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461 added to the greylist database. |
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462 .Pp |
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463 The target counts of embargoed messages are reported to the DCC network |
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464 to improve the detection of bulk mail. |
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465 .It Fl W Xo |
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466 .Sm off |
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467 .Op Ar rate |
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468 .Op Ar ,chg |
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469 .Op Ar ,dbsize |
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470 .Sm on |
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471 .Xc |
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472 controls quick database cleaning. |
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473 If the database is larger than |
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474 .Ar dbsize , |
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475 it seems that the database has not recently and is not about to be cleaned, |
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476 .Nm |
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477 is receiving fewer than |
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478 .Ar rate |
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479 requests per second, |
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480 and if telling DCC clients that the database is about to be cleaned |
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481 reduces that rate by |
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482 .Ar chg Ns %, |
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483 then |
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484 .Nm |
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485 starts |
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486 .Xr dbclean 8 |
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487 for a quick database cleaning. |
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|
488 The cleaning is abandoned if it takes too long. |
|
|
489 The default values are equivalent to |
|
|
490 .Bk -words |
|
|
491 .Fl W Ar 1.0,40.0,RSS |
|
|
492 where |
|
|
493 .Ar RSS |
|
|
494 is the maximum dccd resident set |
|
|
495 displayed the system log by |
|
|
496 .Fl d |
|
|
497 when |
|
|
498 .Nm starts . |
|
|
499 .Ek |
|
|
500 .It Fl K Xo |
|
|
501 .Sm off |
|
|
502 .Op Ar no- |
|
|
503 .Ar type |
|
|
504 .Sm on |
|
|
505 .Xc |
|
|
506 marks checksums of |
|
|
507 .Ar type |
|
|
508 (not) be kept |
|
|
509 or counted in the database unless they appear in the whitelist. |
|
|
510 Explicit settings add to or remove from the initial contents of the list, |
|
|
511 which is equivalent to |
|
|
512 .Fl K Ar Body |
|
|
513 .Fl K Ar Fuz1 |
|
|
514 .Fl K Ar Fuz2 . |
|
|
515 .It Fl T Ar tracemode |
|
|
516 causes the server to trace or record some operations. |
|
|
517 .Ar tracemode |
|
|
518 must be one of the following: |
|
|
519 .Bl -tag -width FLOOD2 -offset 2n -compact |
|
|
520 .It Ar ADMN |
|
|
521 administrative requests from the control program, |
|
|
522 .Xr cdcc 8 |
|
|
523 .It Ar ANON |
|
|
524 errors by anonymous clients |
|
|
525 .It Ar CLNT |
|
|
526 errors by authenticated clients |
|
|
527 .It Ar RLIM |
|
|
528 rate-limited messages |
|
|
529 .It Ar QUERY |
|
|
530 all queries and reports |
|
|
531 .It Ar RIDC |
|
|
532 some messages concerning the report-ID cache that is used |
|
|
533 to detect duplicate reports from clients |
|
|
534 .It Ar FLOOD |
|
|
535 messages about inter-server flooding connections |
|
|
536 .It Ar FLOOD2 |
|
|
537 messages about flooded reports |
|
|
538 .It Ar IDS |
|
|
539 unknown server-IDs in flooded reports |
|
|
540 .It Ar BL |
|
|
541 requests from clients in the |
|
|
542 .Pa blacklist |
|
|
543 file. |
|
|
544 .It Ar DB |
|
|
545 odd database events including long chains of duplicate checksums |
|
|
546 .It Ar WLIST |
|
|
547 reports of whitelisted checksums from authenticated, not anonymous DCC clients |
|
|
548 .El |
|
|
549 The default is |
|
|
550 .Ar ANON CLNT . |
|
|
551 .It Fl u Ar anon-delay Ns Op Ar *inflate |
|
|
552 changes the number of milliseconds anonymous or unauthenticated clients |
|
|
553 must wait for answers to their queries and reports. |
|
|
554 The purpose of this delay is to discourage large anonymous clients. |
|
|
555 The |
|
|
556 .Ar anon-delay |
|
|
557 is multiplied by 1 plus the number of recent anonymous requests from |
|
|
558 an IP address divided by the |
|
|
559 .Ar inflate |
|
|
560 value. |
|
|
561 .Pp |
|
|
562 The string |
|
|
563 .Ar FOREVER |
|
|
564 turns off all anonymous or unauthenticated access not only |
|
|
565 for checksum queries and reports but also |
|
|
566 .Xr cdcc 8 |
|
|
567 .Ic stats |
|
|
568 requests. |
|
|
569 A missing value for |
|
|
570 .Ar inflate |
|
|
571 turns off inflation. |
|
|
572 .Pp |
|
|
573 The default value is |
|
|
574 .Ar 50,none , |
|
|
575 except when |
|
|
576 .Fl G |
|
|
577 is used in which case |
|
|
578 .Ar FOREVER |
|
|
579 is assumed and required. |
|
|
580 .It Fl C Ar dbclean |
|
|
581 changes the default name or path of the program used to rebuild |
|
|
582 the hash table when it becomes too full. |
|
|
583 The default value is |
|
|
584 .Pa @libexecdir@/dbclean |
|
|
585 in the |
|
|
586 .Pa @libexecdir@ |
|
|
587 directory. |
|
|
588 The value can include arguments as in |
|
|
589 .Ar -C '$DCC_LIBEXEC/dbclean -F' . |
|
|
590 .Pp |
|
|
591 Dbclean |
|
|
592 .Em should not |
|
|
593 be run by |
|
|
594 .Nm |
|
|
595 except in emergencies such as database corruption or hash table overflow. |
|
|
596 .Xr Dbclean 8 |
|
|
597 should be run daily with the @libexecdir@/cron-dccd cron script |
|
|
598 .It Fl L Ar ltype,facility.level |
|
|
599 specifies how messages should be logged. |
|
|
600 .Ar Ltype |
|
|
601 must be |
|
|
602 .Ar error , |
|
|
603 .Ar info , |
|
|
604 or |
|
|
605 .Ar off |
|
|
606 to indicate which of the two types of messages are being controlled or |
|
|
607 to turn off all |
|
|
608 .Xr syslog 3 |
|
|
609 messages from |
|
|
610 .Nm . |
|
|
611 .Ar Level |
|
|
612 must be a |
|
|
613 .Xr syslog 3 |
|
|
614 level among |
|
|
615 .Ar EMERG , |
|
|
616 .Ar ALERT , |
|
|
617 .Ar CRIT , ERR , |
|
|
618 .Ar WARNING , |
|
|
619 .Ar NOTICE , |
|
|
620 .Ar INFO , |
|
|
621 and |
|
|
622 .Ar DEBUG . |
|
|
623 .Ar Facility |
|
|
624 must be among |
|
|
625 .Ar AUTH , |
|
|
626 .Ar AUTHPRIV , |
|
|
627 .Ar CRON , |
|
|
628 .Ar DAEMON , |
|
|
629 .Ar FTP , |
|
|
630 .Ar KERN , |
|
|
631 .Ar LPR , |
|
|
632 .Ar MAIL , |
|
|
633 .Ar NEWS , |
|
|
634 .Ar USER , |
|
|
635 .Ar UUCP , |
|
|
636 and |
|
|
637 .Ar LOCAL0 |
|
|
638 through |
|
|
639 .Ar LOCAL7 . |
|
|
640 The default is equivalent to |
|
|
641 .Dl Fl L Ar info,MAIL.NOTICE Fl L Ar error,MAIL.ERR |
|
|
642 .It Fl R Xo |
|
|
643 .Sm off |
|
|
644 .Op Ar RL_SUB , |
|
|
645 .Op Ar RL_ANON , |
|
|
646 .Op Ar RL_ALL_ANON , |
|
|
647 .Op Ar RL_BUGS |
|
|
648 .Xc |
|
|
649 .Sm on |
|
|
650 sets one or more of the four rate-limits. |
|
|
651 .Ar RL_SUB |
|
|
652 limits the number of DCC transactions per second from subscribers |
|
|
653 or DCC clients with known client-IDs and passwords. |
|
|
654 This limit applies to each IP address independently. |
|
|
655 .Pp |
|
|
656 .Ar RL_ANON |
|
|
657 limits the number of DCC transactions per second from anonymous DCC clients. |
|
|
658 This limit applies to each IP address independently. |
|
|
659 It is better to use |
|
|
660 .Fl u |
|
|
661 than to change this value to exclude anonymous clients. |
|
|
662 .Pp |
|
|
663 .Ar RL_ALL_ANON |
|
|
664 limits the number of DCC transactions per second from all anonymous DCC clients. |
|
|
665 This limit applies to all anonymous clients as a group, regardless of their |
|
|
666 IP addresses. |
|
|
667 .Pp |
|
|
668 .Ar RL_BUGS |
|
|
669 limits the number of complaints or error messages per second for all |
|
|
670 anonymous DCC clients as a group as well as for each DCC client by IP |
|
|
671 address. |
|
|
672 .Pp |
|
|
673 The default is equivalent to |
|
|
674 .Fl R Ar 400,50,600,0.1 |
|
|
675 .El |
|
|
676 .Sh FILES |
|
|
677 .Bl -hang -width @prefix@ -compact |
|
|
678 .It Pa @prefix@ |
|
|
679 is the DCC home directory containing data and control files. |
|
|
680 .It Pa dcc_db |
|
|
681 is the database of mail checksums. |
|
|
682 .It Pa dcc_db.hash |
|
|
683 is the mail checksum database hash table. |
|
|
684 .It Pa grey_db |
|
|
685 is the database of greylist checksums. |
|
|
686 .It Pa grey_db.hash |
|
|
687 is the greylist database hash table. |
|
|
688 .It Pa flod |
|
|
689 contains lines controlling DCC flooding of the form: |
|
|
690 .br |
|
|
691 .Bd -ragged -compact |
|
|
692 .Ar host Ns Xo |
|
|
693 .Sm off |
|
|
694 .Op Ar ,rport |
|
|
695 .Op Ar ;src Op Ar ,lport |
|
|
696 .Sm on |
|
|
697 .Xc |
|
|
698 .Ar rem-ID |
|
|
699 .Op Ar passwd-ID Op Ar o-opt Op Ar i-opt |
|
|
700 .Ed |
|
|
701 where absent optional values are signaled with "-" and |
|
|
702 .Bl -hang -offset 1n -width 2n -compact |
|
|
703 .It Ar host |
|
|
704 is the IP address or name of a DCC server and |
|
|
705 .Ar rport |
|
|
706 is the name or number of the TCP port used by the remote server. |
|
|
707 .It Ar src |
|
|
708 and |
|
|
709 .Ar lport |
|
|
710 are the IP address or host name and TCP port |
|
|
711 from which the outgoing flooding connection should come. |
|
|
712 Incoming flooding connections must arrive at an address and port |
|
|
713 specified with |
|
|
714 .Fl a . |
|
|
715 .It Ar rem-id |
|
|
716 is the server-ID of the remote DCC server. |
|
|
717 .It Ar passwd-ID |
|
|
718 is a server-ID that is not assigned to a server, |
|
|
719 but whose first password is used to sign |
|
|
720 checksum reports sent to the remote system. |
|
|
721 Either of its passwords are required with incoming reports. |
|
|
722 If it is absent or "-", outgoing floods are signed with the first |
|
|
723 password of the local server in the |
|
|
724 .Pa ids |
|
|
725 file and incoming floods must be signed with either password of |
|
|
726 the remote server-ID. |
|
|
727 .It Ar i-opt Li and Ar o-opt |
|
|
728 are comma separated lists of |
|
|
729 .Bl -hang -offset 1n -width 2n -compact |
|
|
730 .It Ar off |
|
|
731 turns off flooding to the remote or local system. |
|
|
732 .It Ar traps |
|
|
733 indicates that |
|
|
734 the remote sending or local receiving system has only spam traps. |
|
|
735 .It Ar no-del |
|
|
736 says checksum delete requests are refused by the remote or local server |
|
|
737 and so turns off sending or accepting delete requests, respectively. |
|
|
738 By default, delete requests are sent to remote servers and accepted |
|
|
739 in incoming floods if and only if the peers are exchanging DCC reputations. |
|
|
740 .It Ar del |
|
|
741 says delete requests are accepted by the remote or local server. |
|
|
742 .It Ar no-log-del |
|
|
743 turns off logging of incoming requests to delete checksums. |
|
|
744 .It Ar passive |
|
|
745 is used to tell a server outside a firewall to expect a peer |
|
|
746 inside to create both of the pair |
|
|
747 of input and output TCP connections used for flooding. |
|
|
748 The peer inside the firewall should use |
|
|
749 .Ar SOCKS |
|
|
750 or |
|
|
751 .Ar NAT |
|
|
752 on its |
|
|
753 .Pa flod |
|
|
754 file entry for this system. |
|
|
755 .It Ar SOCKS |
|
|
756 is used to tell a server inside a firewall that it should create both |
|
|
757 of the TCP connections used for flooding and that SOCKS protocol should |
|
|
758 be used. |
|
|
759 The peer outside the firewall should use |
|
|
760 .Ar passive |
|
|
761 on its |
|
|
762 .Pa flod |
|
|
763 file entry for this system. |
|
|
764 .It Ar NAT |
|
|
765 differs from |
|
|
766 .Ar SOCKS |
|
|
767 only by not using the SOCKS protocol. |
|
|
768 .It Ar ID1->ID2 |
|
|
769 converts server-ID |
|
|
770 .Ar ID1 |
|
|
771 in flooded reports to server-ID |
|
|
772 .Ar ID2 . |
|
|
773 Either |
|
|
774 .Ar ID1 |
|
|
775 or |
|
|
776 .Ar ID2 |
|
|
777 may be the string |
|
|
778 .Sq self |
|
|
779 to specify the server's own ID. |
|
|
780 .Ar ID1 |
|
|
781 can be the string |
|
|
782 .Sq all |
|
|
783 to specify all server-IDs |
|
|
784 or a pair of server-IDs separated by a dash to specify an inclusive range. |
|
|
785 .Ar ID2 |
|
|
786 can be the string |
|
|
787 .Sq ok |
|
|
788 to send or receive reports without translation |
|
|
789 or the string |
|
|
790 .Sq reject |
|
|
791 to not send outgoing or refuse incoming reports. |
|
|
792 Only the first matching conversion is applied. |
|
|
793 For example, when |
|
|
794 .Sq self->ok,all->reject |
|
|
795 is applied to a locally generated report, |
|
|
796 the first conversion is applied and the second is ignored. |
|
|
797 .It Ar leaf=path-len |
|
|
798 does not send reports with paths longer than |
|
|
799 .Ar path-len |
|
|
800 server-IDs. |
|
|
801 .It Ar IPv4 |
|
|
802 overrides a |
|
|
803 .Fl 6 |
|
|
804 setting for this flooding peer. |
|
|
805 .It Ar IPv6 |
|
|
806 overrides the |
|
|
807 default or an explicit |
|
|
808 .Fl 4 |
|
|
809 setting. |
|
|
810 .It Ar vers |
|
|
811 specifies the version of the DCC flooding protocol used by the remote |
|
|
812 DCC server with a string such as |
|
|
813 .Sq version2 . |
|
|
814 .It Ar trace |
|
|
815 sends information about a single peer like the |
|
|
816 .Xr cdcc 8 |
|
|
817 command |
|
|
818 .Ic trace FLOOD on |
|
|
819 does for all peers. |
|
|
820 .It Ar trace2 |
|
|
821 sends information about individual flooded reports like the |
|
|
822 .Xr cdcc 8 |
|
|
823 command |
|
|
824 .Ic trace FLOOD2 on |
|
|
825 does for all peers. |
|
|
826 .El |
|
|
827 .El |
|
|
828 .It Pa grey_flod |
|
|
829 is the equivalent of |
|
|
830 .Pa flod |
|
|
831 used by |
|
|
832 .Nm |
|
|
833 when it is a greylist server. |
|
|
834 .It Pa flod.map |
|
|
835 is an automatically generated file in which |
|
|
836 .Nm |
|
|
837 records its progress sending or flooding reports to DCC peers. |
|
|
838 .It Pa grey_flod.map |
|
|
839 is the equivalent of |
|
|
840 .Pa flod.map used by |
|
|
841 .Nm |
|
|
842 when it is a greylist server. |
|
|
843 .It Pa ids |
|
|
844 contains the IDs and passwords known by the DCC server. |
|
|
845 An |
|
|
846 .Pa ids |
|
|
847 file that can be read by others cannot be used. |
|
|
848 It contains blank lines, comments starting |
|
|
849 with "#" and lines of the form: |
|
|
850 .Bd -ragged -compact -offset indent |
|
|
851 .Sm off |
|
|
852 .Ar id |
|
|
853 .Op Ar ,rpt-ok |
|
|
854 .Op Ar ,delay=ms Ns Op Ar *inflate |
|
|
855 .Sm on |
|
|
856 .Ar passwd1 Op Ar passwd2 |
|
|
857 .Ed |
|
|
858 where |
|
|
859 .Bl -hang -offset 1n -width 2n -compact |
|
|
860 .It Ar id |
|
|
861 is a DCC |
|
|
862 .Ar client-ID |
|
|
863 or |
|
|
864 .Ar server-ID . |
|
|
865 .It Ar Rpt-ok |
|
|
866 if present overrides |
|
|
867 .Fl Q |
|
|
868 by saying that this client is trusted |
|
|
869 to report only checksums for unsolicited bulk mail. |
|
|
870 .It Ar delay=ms Ns Op Ar *inflate |
|
|
871 delays answers to systems using the client |
|
|
872 .Ar id . |
|
|
873 The |
|
|
874 .Ar delay |
|
|
875 in milliseconds is multiplied by 1 plus the number of recent requests from |
|
|
876 an IP address using |
|
|
877 .Ar id |
|
|
878 divided by the |
|
|
879 .Ar inflate |
|
|
880 value. |
|
|
881 See |
|
|
882 .Fl u . |
|
|
883 .It Ar passwd1 |
|
|
884 is the password currently used by clients with identifier |
|
|
885 .Ar id . |
|
|
886 It is a 1 to 32 character string that does not contain |
|
|
887 blank, tab, newline or carriage return characters. |
|
|
888 .It Ar passwd2 |
|
|
889 is the optional next password that those clients will use. |
|
|
890 A DCC server accepts either password if both are present in the file. |
|
|
891 .El |
|
|
892 Both passwords can be absent if the entry not used except to tell |
|
|
893 .Nm |
|
|
894 that server-IDs in the flooded reports are valid. |
|
|
895 The string |
|
|
896 .Em unknown |
|
|
897 is equivalent to the null string. |
|
|
898 .It Pa whitelist |
|
|
899 contains the DCC server whitelist. |
|
|
900 It is not used directly but is loaded into the database when |
|
|
901 .Xr dbclean 8 |
|
|
902 is run. |
|
|
903 .It Pa grey_whitelist |
|
|
904 contains the greylist server whitelist. |
|
|
905 It is not used directly but is loaded into the database when |
|
|
906 .Xr dbclean 8 |
|
|
907 is run with |
|
|
908 .Fl G . |
|
|
909 .It Pa blacklist |
|
|
910 if present, contains a list of IP addresses and blocks of IP addresses |
|
|
911 DCC clients that are ignored. |
|
|
912 Each line in the file should be blank, a comment starting with '#', |
|
|
913 or an IP address or block of IP addresses in the form |
|
|
914 .Bd -ragged -compact -offset indent |
|
|
915 .Op Ar trace, |
|
|
916 .Op Ar ok, |
|
|
917 .Op Ar bad |
|
|
918 .No xxx.xxx.xxx.xxx Ns Op /yy |
|
|
919 .Ed |
|
|
920 Changes to the file are automatically noticed and acted upon within |
|
|
921 a few minutes. |
|
|
922 Addresses or blocks of addresses can be preceded with |
|
|
923 .Em ok |
|
|
924 to "punch holes" |
|
|
925 in blacklisted blocks or with |
|
|
926 .Em trace |
|
|
927 to log activity. |
|
|
928 This mechanism is intended for no more than a few dozen blocks of addresses. |
|
|
929 .It Pa dccd_clients |
|
|
930 contains client IP addresses and activity counts. |
|
|
931 .It Pa grey_clients |
|
|
932 contains greylist client IP addresses and activity counts. |
|
|
933 .El |
|
|
934 .Sh EXAMPLES |
|
|
935 .Nm |
|
|
936 is usually started with other system daemons with something like the |
|
|
937 script |
|
|
938 .Pa @libexecdir@/rcDCC . |
|
|
939 That scripts uses values in @prefix@/dcc_conf to start the server. |
|
|
940 With the argument |
|
|
941 .Em stop , |
|
|
942 .Pa @libexecdir@/rcDCC |
|
|
943 can be used to stop the daemon. |
|
|
944 .Pp |
|
|
945 The database grows too large unless old reports are removed. |
|
|
946 .Xr dbclean 8 |
|
|
947 should be run daily with the @libexecdir@/cron-dccd cron script |
|
|
948 .Sh SEE ALSO |
|
|
949 .Xr cdcc 8 , |
|
|
950 .Xr dcc 8 , |
|
|
951 .Xr dbclean 8 , |
|
|
952 .Xr dblist 8 , |
|
|
953 .Xr dccifd 8 , |
|
|
954 .Xr dccm 8 , |
|
|
955 .Xr dccproc 8 . |
|
|
956 .Xr dccsight 8 , |
|
|
957 .Sh HISTORY |
|
|
958 .Nm |
|
|
959 is based on an idea from Paul Vixie. |
|
|
960 It was designed and written at Rhyolite Software, starting in 2000. |
|
|
961 This document describes version 1.3.103. |
