1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
|
cdcc(8) Distributed Checksum Clearinghouse cdcc(8)
NNAAMMEE
ccddcccc -- Control Distributed Checksum Clearinghouse
SSYYNNOOPPSSIISS
ccddcccc [--VVddqq] [--hh _h_o_m_e_d_i_r] [--cc _i_d_s] [_o_p_1 _o_p_2 _._._. [_-]]
DDEESSCCRRIIPPTTIIOONN
CCddcccc is used to clear, control, and query the control file used by Dis-
tributed Checksum Clearinghouse clients such as dccm(8). The host names,
UDP port numbers, IDs, and passwords local clients use to talk to servers
as well as IP addresses, round trip times, and other information are con-
tained in the _m_a_p file. While ccddcccc is set-UID, it uses the real UID only
when accessing the _m_a_p file. It refuses to display sensitive information
such as passwords unless the real UID is the same as the effective UID.
Note that ccddcccc needs to be set to a UID that can read and write the _m_a_p
file, but that UID need not be 0.
CCddcccc is also used to send commands to DCC servers to tell them to stop,
reload their lists of DCC IDs, turn on tracing, and so forth.
Many commands sent to DCC servers require a numeric DCC ID and a password
recognized by the server. A DCC password is a 1-32 character string that
does not contain blank, tab, newline or carriage return characters. The
ID is specified with the iidd operation. If ccddcccc is run with a real UID
that can read the _i_d_s file and a password is not specified (see the
ppaasssswwoorrdd operation), then the current password for the specified ID in
the _i_d_s file will be used. If no _i_d_s file is available and a password
and DCC ID are not specified, ccddcccc uses the anonymous DCC client-ID. DCC
servers do not expect a password from clients using the anonymous client-
ID, but they also won't honor control requests.
Operations that modify the _m_a_p file can only be performed when the real
UID is sufficient to modify the file directly. Trying to perform an
operation that requires a password without specifying a server-ID or
without using a UID that can access the _i_d_s file produces an error mes-
sage complaining about a "privileged operation."
Commands and operations are read from the command line or from stdin. A
series of _o_p_1 _o_p_2 _._._. operations followed a _- (a dash) causes operations
to be read from stdin after the command line operations are processed.
Semi-colons or newlines separate commands in UNIX command-line "words,"
as well as when commands are read from stdin. Since each command line
operation must be a shell "word," quotes are often required as in
% cdcc "load map.txt"
or
% cdcc "host localhost;info" stats
OOPPTTIIOONNSS
The following options are available:
--VV displays the version of the DCC controller.
--dd enables debugging output from the DCC client library. Additional --dd
options increase the number of messages. --qq quiets initial com-
plaints about the map file, and some messages about successful com-
mands.
--hh _h_o_m_e_d_i_r
overrides the default DCC home directory, which is often /var/dcc.
See the hhoommeeddiirr operation.
--cc _i_d_s
specifies file containing DCC IDs and passwords known by the local
DCC server. An _i_d_s file that can be read by others cannot be used.
The format of the _i_d_s file is described in dccd(8).
_o_p_1 _o_p_2 _._._.
are operations or commands such as "id 100; stop". Commands or
operations specified on the command line are performed before the
first interactive request. The last command can be _- to specify
that additional commands should be read from stdin.
OOPPEERRAATTIIOONNSS
Local operations include the following:
hheellpp [_c_o_m_m_a_n_d]
lists information about one or all available commands and opera-
tions.
eexxiitt stops ccddcccc
ggrreeyy [_o_n | _o_f_f]
switches between DCC and greylist servers.
hhoommeeddiirr [_p_a_t_h]
displays or specifies the DCC home directory.
ffiillee [_m_a_p]
displays or specifies the name or path of the map file. The string
"-" specifies the default file _m_a_p in the DCC home directory.
nneeww mmaapp [_m_a_p]
creates a new, empty file for DCC server host names, port numbers,
passwords, and so forth. There must not already be a file of the
same name. The default is _m_a_p in the DCC home directory.
ddeelleettee _h_o_s_t[,_p_o_r_t]
deletes the entry in the _m_a_p file for _h_o_s_t and UDP _p_o_r_t_. If
greylist mode has been set with the ggrreeyy oonn command, the entry for
the grelist server at _h_o_s_t is deleted.
aadddd _h_o_s_t[,_p_o_r_t] [_R_T_T_+_a_d_j|_R_T_T_-_a_d_j] [_G_r_e_y_l_i_s_t] [_c_l_i_e_n_t_-_I_D [password]]
adds an entry to the _m_a_p file. The _p_o_r_t can be "-" to specify the
default DCC server port number.
An adjustment to the round trip time is a multiple of 10 millisec-
onds between -4000 and +4000 following the string _R_T_T. The adjust-
ment is added to the average measured round trip time when the DCC
client software picks the "nearest" DCC server, or the server with
the smallest RTT. If an IP address is mentioned more than once in
the list of servers, for example because it is among the addresses
for more than one server name, conflicts among RTT adjustments are
resolved by picking the adjustment with the largest absolute value.
_G_r_e_y_l_i_s_t marks an entry for a greylist servers. _G_r_e_y_l_i_s_t is
assumed if greylist mode has been set with the ggrreeyy oonn command, See
dccd(8).
If both the client-ID and the password are absent, the anonymous
client-ID, 1, is used. The string _a_n_o_n is equivalent to the anony-
mous client-ID. A null password string is assumed if the password
is missing and the client-ID is 1 or also missing.
llooaadd _i_n_f_o_-_f_i_l_e
loads the current parameter file with the host names, port numbers,
IDs, and passwords in _i_n_f_o_-_f_i_l_e. Standard input is understood if
_i_n_f_o_-_f_i_l_e is "-".
A suitable file can be created with the iinnffoo operation. It con-
sists of blank lines and comment lines starting with '#' other
lines in the same format as the arguments to the aadddd and llooaadd oper-
ations. Note that output of the iinnffoo command will lack passwords
unless it is run by a privileged user.
hhoosstt [_h_o_s_t_n_a_m_e]
specifies the host name of the DCC server to which commands should
be sent. If _h_o_s_t_n_a_m_e is "-", the current default DCC server is
chosen.
ppoorrtt [_p_o_r_t]
specifies the UDP port number of the DCC server to which commands
should be sent. The default is 6277 or 6276 depending on the set-
ting of the greylist mode controlled with the ggrreeyy command.
ppaasssswwoorrdd _s_e_c_r_e_t
specifies the password with which to sign commands sent to the DCC
server specified with the sseerrvveerr and ppoorrtt operations.
iidd [_I_D]
specifies or displays the numeric DCC ID for commands sent to the
DCC server specified with the sseerrvveerr and ppoorrtt operations. If no
password is specified with the ppaasssswwoorrdd command, the password is
sought in the local _i_d_s.
iinnffoo [--NN]
displays information about the connections to DCC servers. It
starts with the current date and name of the current _m_a_p file or
says that ccddcccc is using the implicit file created with the sseerrvveerr
and ppoorrtt operations. It then says when host names will next be
resolved into IP addresses, the smallest round trip time to the IP
addresses of known DCC servers. The host name, UDP port number (or
dash if it is the default), DCC client-ID, and password (if ccddcccc is
used by a privileged user) are shown in one line per configured DCC
server.
The currently preferred IP address is indicated by an asterisk.
The "brand" of the server, its DCC ID, and its IP address are dis-
played in one line per IP address. The performance of the server
at each IP address in the most recent 32 operations is displayed in
a second line. The second line ends with the measured delay
imposed by the server on requests with this client's ID.
--NN displays the reverse DNS name of each server.
RRTTTT [--NN]
measures the round trip time to the DCC servers. It does this by
discarding accumulated information and forcing a probe of all
listed server IP addresses.
_B_e_w_a_r_e that when run with sufficient privilege, the RRTTTT operation
is like the iinnffoo and llooaadd operations and displays cleartext pass-
words.
--NN displays the reverse DNS name of each server.
ddeebbuugg [_o_n | _o_f_f | _T_T_L_=_x]
increases or decreases debugging information from the DCC client
library or sets the IP TTL on queries to the server. See --dd.
Some systems do not include the functions required to change the IP
TTL. Others apparently including Microsoft Windows XP include
required functions but have no apparent effect.
IIPPvv66 [_o_n | _o_f_f]
sets a switch to cause clients using the map file to try to use
IPv6.
SSOOCCKKSS [_o_n _o_f_f]
sets a switch to cause DCC clients using the map to use the SOCKS5
protocol, if they have been built with a SOCKS library. The socks
library linked with the DCC client must be configured appropri-
ately, often including knowing which DCC servers must be connected
via the SOCKS proxy and which can be reached directly. DCC clients
use SOCKS functions such as Rsendto() with all or no servers
depending on the setting of this switch.
DDCCCC SSEERRVVEERR CCOOMMMMAANNDDSS
Commands that can be sent to a DCC server include the following. Most of
the commands must be used with the server's _I_D specified with the iidd com-
mand. The specified ID is included in the commands sent to the server
The command itself is digitally signed with the first password associated
with the ID in the _i_d_s file. The server requires that the signature
match one of the passwords associated with the ID in its _i_d_s file.
ddeellcckk ttyyppee hheexx11 hheexx22 hheexx33 hheexx44
asks the server to delete the _t_y_p_e checksum with value _h_e_x_1 _h_e_x_2
_h_e_x_3 _h_e_x_4. The type and checksum values can be found in dccproc(8)
and dccm(8) log files or computed with _d_c_c_p_r_o_c_-_Q_C.
There are very few situations where it makes sense to bother to
delete checksums. For example, mail that was accidentally reported
with a target count of "MANY" is either private and so will not be
seen by other people and so will not be affected, or it is bulk and
its source so must have already been white-listed by recipients.
ssttaattss [_a_l_l | _c_l_e_a_r]
displays current status and statistics from the current DCC server
or for _a_l_l known DCC servers.
cclliieennttss [--nn] [--ss] [--ii] [--aa] [_m_a_x [_t_h_o_l_d]]
displays some of the clients recently seen by the server.
cclliieennttss --nn displays only the IP addresses and not the names of
clients. cclliieennttss --ss sorts the clients by the number of requests
they have made. cclliieennttss --ii counts clients with the same client-ID
as single entities. cclliieennttss --aa produces 24 hour average values.
cclliieennttss _m_a_x displays only the most recent _m_a_x clients. cclliieennttss _m_a_x
_t_h_o_l_d displays the most recent _m_a_x clients that have made at least
_t_h_o_l_d requests.
The mechanism that implements this command involves asking the DCC
server for the first approximately 100 clients, then the second
about 100, and so on, If entries change position in the complete
list maintained by the server between requests, the displayed list
will have duplicate or missing entries.
Only clients heard from since the server was started or ssttaattss cclleeaarr
was last used are displayed.
ssttoopp
tells the DCC server to exit.
rreellooaadd IIDDss
tells the DCC server to reload its DCC _i_d_s file. This is handy to
cause the server to notice changes in the file.
fflloooodd cchheecckk
tells the DCC server to check for changes in the _f_l_o_d file and try
to restart any of the streams to peers that are broken.
fflloooodd sshhuuttddoowwnn
tells the DCC server to cleanly stop flooding checksums to and from
peers. The server will wait for sending and receiving peers to
agree to stop. Each fflloooodd sshhuuttddoowwnn or fflloooodd hhaalltt request increases
a count of reasons why the server should not flood checksums.
fflloooodd hhaalltt
tells the DCC server to abruptly stop flooding checksums to and from
peers.
fflloooodd rreewwiinndd _s_e_r_v_e_r_-_I_D
tells the DCC server to ask its peer with _s_e_r_v_e_r_-_I_D to rewind and
resend its stream of checksums.
fflloooodd ffffwwdd iinn _s_e_r_v_e_r_-_I_D
tells the DCC server to ask its peer to "fast forward" or skip to
the end of the incoming flood.
fflloooodd ffffwwdd oouutt _s_e_r_v_e_r_-_I_D
tells the DCC server to "fast forward" or skip to the current end of
the flood to its peer.
fflloooodd rreessuummee
tells the DCC server to reduce the number of reasons to not flood
checksums increased by fflloooodd sshhuuttddoowwnn and fflloooodd hhaalltt.. When the num-
ber of reasons reaches zero, the server tries to resume flooding.
fflloooodd lliisstt
displays the list of current incoming and outgoing floods. Each
line contains the server-ID of the peer, the IP address and port
used for the outgoing flood, the address for the incoming flood if
different, and the host name. Only the server-IDs of flooding peers
are disclosed with the server's ID.
fflloooodd ssttaattss [cclleeaarr] { _s_e_r_v_e_r_-_I_D | _a_l_l }
displays counts of checksum reports sent and received by the current
flooding connections to and from _s_e_r_v_e_r_-_I_D or _a_l_l flooding connec-
tions and then optionally clears the counts.
DDBB uunnlloocckk
is used by ddbbcclleeaann to tell the server that the database expiration
has begun.
DDBB nneeww
is used by ddbbcclleeaann to tell the server that the database cleaning is
complete.
ttrraaccee _m_o_d_e _{_o_n_|_o_f_f_}
turns the server's tracing _m_o_d_e on or off. _M_o_d_e must be one of:
_A_L_L all tracing
_A_D_M_N administrative requests from ccddcccc
_A_N_O_N errors by anonymous clients
_C_L_N_T errors by authenticated clients
_R_L_I_M rate-limited messages
_Q_U_E_R_Y all queries and reports
_R_I_D_C messages concerning the report-ID cache that is used to
detect duplicate reports from clients
_F_L_O_O_D messages about inter-server flooding
_I_D_S unknown server-IDs in flooded reports
_B_L blacklisted clients
ccddcccc exits 0 on success, and >0 if an error occurs in operations speci-
fied on the command line.
FFIILLEESS
/var/dcc DCC home directory
map memory mapped file in the home DCC home directory of server
host names, port numbers, passwords, measured round trip times
(RTT), and so forth.
ids list of IDs and passwords, as described in dccd(8). It is only
required by systems running the DCC server, but is used by ccddcccc
if available.
SSEEEE AALLSSOO
dbclean(8), dcc(8), dccd(8), dblist(8), dccifd(8), dccm(8), dccproc(8),
dccsight(8).
HHIISSTTOORRYY
Implementation of ccddcccc was started at Rhyolite Software in 2000. This
describes version 1.2.74.
FreeBSD 4.9 March 20, 2005 FreeBSD 4.9
|
