]>
Commit | Line | Data |
---|---|---|
1 | /* | |
2 | * charybdis: an advanced ircd | |
3 | * ratelimit.c: Per-client ratelimiting for high-bandwidth commands. | |
4 | * | |
5 | * Copyright (c) 2012 Keith Buck <mr_flea -at- esper.net> | |
6 | * | |
7 | * Permission to use, copy, modify, and/or distribute this software for any | |
8 | * purpose with or without fee is hereby granted, provided that the above | |
9 | * copyright notice and this permission notice is present in all copies. | |
10 | * | |
11 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
12 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED | |
13 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE | |
14 | * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, | |
15 | * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES | |
16 | * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR | |
17 | * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
18 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, | |
19 | * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING | |
20 | * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | |
21 | * POSSIBILITY OF SUCH DAMAGE. | |
22 | */ | |
23 | ||
24 | #include "stdinc.h" | |
25 | #include "s_conf.h" | |
26 | #include "s_stats.h" | |
27 | #include "ratelimit.h" | |
28 | #include "s_assert.h" | |
29 | ||
30 | /* | |
31 | * ratelimit_client(struct Client *client_p, int penalty) | |
32 | * | |
33 | * Applies a penalty to a client for executing a rate-limited command. | |
34 | * | |
35 | * Inputs: | |
36 | * - the client to be rate-limited | |
37 | * - the penalty to apply | |
38 | * | |
39 | * Outputs: | |
40 | * - 1 if the user has been penalized and the command should be | |
41 | * allowed to execute | |
42 | * - 0 if the command should not execute and the user has not | |
43 | * been penalized (they are executing commands too fast and have | |
44 | * been rate-limited) | |
45 | * The caller should return RPL_LOAD2HI | |
46 | * | |
47 | * Side effects: | |
48 | * - The ratelimit for the user will be initialized if it hasn't | |
49 | * been initialized yet. | |
50 | */ | |
51 | int ratelimit_client(struct Client *client_p, unsigned int penalty) | |
52 | { | |
53 | s_assert(client_p); | |
54 | s_assert(MyClient(client_p)); | |
55 | ||
56 | if (!client_p->localClient->ratelimit) | |
57 | { | |
58 | /* Not initialized yet - do it now. */ | |
59 | client_p->localClient->ratelimit = rb_current_time() - ConfigFileEntry.max_ratelimit_tokens; | |
60 | } | |
61 | ||
62 | /* Don't make it impossible to execute anything. */ | |
63 | if (penalty > ConfigFileEntry.max_ratelimit_tokens) | |
64 | penalty = ConfigFileEntry.max_ratelimit_tokens; | |
65 | ||
66 | if (client_p->localClient->ratelimit <= rb_current_time() - ConfigFileEntry.max_ratelimit_tokens) | |
67 | { | |
68 | client_p->localClient->ratelimit = rb_current_time() - ConfigFileEntry.max_ratelimit_tokens + penalty; | |
69 | return 1; | |
70 | } | |
71 | ||
72 | if (client_p->localClient->ratelimit + penalty > rb_current_time()) | |
73 | { | |
74 | ServerStats.is_rl++; | |
75 | return 0; | |
76 | } | |
77 | ||
78 | client_p->localClient->ratelimit += penalty; | |
79 | ||
80 | return 1; | |
81 | } | |
82 | ||
83 | /* | |
84 | * ratelimit_client_who(struct Client *client_p, int penalty) | |
85 | * | |
86 | * Rate-limits a client for a WHO query if they have no remaining "free" | |
87 | * WHO queries to execute. | |
88 | * | |
89 | * Inputs: | |
90 | * - same as ratelimit_client | |
91 | * | |
92 | * Outputs: | |
93 | * - same as ratelimit_client | |
94 | * | |
95 | * Side effects: | |
96 | * - A "free who" token will be removed from the user if one exists. | |
97 | * If one doesn't exist, the user will be ratelimited as normal. | |
98 | */ | |
99 | int ratelimit_client_who(struct Client *client_p, unsigned int penalty) | |
100 | { | |
101 | s_assert(client_p); | |
102 | s_assert(MyClient(client_p)); | |
103 | ||
104 | if (client_p->localClient->join_who_credits) | |
105 | { | |
106 | --client_p->localClient->join_who_credits; | |
107 | return 1; | |
108 | } | |
109 | ||
110 | return ratelimit_client(client_p, penalty); | |
111 | } | |
112 | ||
113 | /* | |
114 | * credit_client_join(struct Client *client_p) | |
115 | * | |
116 | * Gives a user a credit to execute a WHO for joining a channel. | |
117 | * | |
118 | * Inputs: | |
119 | * - the client to be credited | |
120 | * | |
121 | * Outputs: | |
122 | * - (none) | |
123 | * | |
124 | * Side effects: | |
125 | * - (none) | |
126 | */ | |
127 | void credit_client_join(struct Client *client_p) | |
128 | { | |
129 | s_assert(client_p); | |
130 | s_assert(MyClient(client_p)); | |
131 | ||
132 | ++client_p->localClient->join_who_credits; | |
133 | } |