1 /* rrl.h - Response Rate Limiting for NSD. 2 * By W.C.A. Wijngaards 3 * Copyright 2012, NLnet Labs. 4 * BSD, see LICENSE. 5 */ 6 #ifndef RRL_H 7 #define RRL_H 8 #include "query.h" 9 10 /** the classification types for the rrl */ 11 enum rrl_type { 12 /* classification types */ 13 rrl_type_nxdomain = 0x01, 14 rrl_type_error = 0x02, 15 rrl_type_referral = 0x04, 16 rrl_type_any = 0x08, 17 rrl_type_wildcard = 0x10, 18 rrl_type_nodata = 0x20, 19 rrl_type_dnskey = 0x40, 20 rrl_type_positive = 0x80, 21 rrl_type_rrsig = 0x100, 22 23 /* all classification types */ 24 rrl_type_all = 0x1ff, 25 /* to distinguish between ip4 and ip6 netblocks, used in code */ 26 rrl_ip6 = 0x8000 27 }; 28 29 /** Number of buckets */ 30 #define RRL_BUCKETS 1000000 31 /** default rrl limit, in 2x qps , the default is 200 qps */ 32 #define RRL_LIMIT 400 33 /** default whitelist rrl limit, in 2x qps, default is thus 2000 qps */ 34 #define RRL_WLIST_LIMIT 4000 35 36 /** 37 * Initialize for n children (optional, otherwise no mmaps used) 38 * ratelimits lm and wlm are in qps (this routines x2s them for internal use). 39 */ 40 void rrl_mmap_init(int numch, size_t numbuck, size_t lm, size_t wlm); 41 42 /** 43 * Initialize rate limiting (for this child server process) 44 */ 45 void rrl_init(size_t ch); 46 47 /** 48 * Process query that happens, the query structure contains the 49 * information about the query and the answer. 50 * returns true if the query is ratelimited. 51 */ 52 int rrl_process_query(query_type* query); 53 54 /** 55 * Deny the query, with slip. 56 * Returns DISCARD or PROCESSED(with TC flag). 57 */ 58 query_state_type rrl_slip(query_type* query); 59 60 /** convert classification type to string */ 61 const char* rrltype2str(enum rrl_type c); 62 /** convert string to classification type */ 63 enum rrl_type rrlstr2type(const char* s); 64 65 /** for unit test, update rrl bucket; return rate */ 66 uint32_t rrl_update(query_type* query, uint32_t hash, uint64_t source, 67 uint16_t flags, int32_t now, uint32_t lm); 68 /** set the rate limit counters, pass variables in qps */ 69 void rrl_set_limit(size_t lm, size_t wlm); 70 71 #endif /* RRL_H */ 72