diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Doc | 2 | ||||
| -rw-r--r-- | lib/Modules | 1 | ||||
| -rw-r--r-- | lib/birdlib.h | 40 | ||||
| -rw-r--r-- | lib/tbf.c | 29 |
4 files changed, 64 insertions, 8 deletions
@@ -1,7 +1,7 @@ H Library functions S ip.c ipv4.c ipv6.c S lists.c -S checksum.c bitops.c patmatch.c printf.c xmalloc.c +S checksum.c bitops.c patmatch.c printf.c xmalloc.c tbf.c D resource.sgml S resource.c S mempool.c diff --git a/lib/Modules b/lib/Modules index c585c9a8..7131f0b2 100644 --- a/lib/Modules +++ b/lib/Modules @@ -19,6 +19,7 @@ resource.c resource.h slab.c socket.h +tbf.c unaligned.h xmalloc.c printf.c diff --git a/lib/birdlib.h b/lib/birdlib.h index 04fb7fed..c489c45f 100644 --- a/lib/birdlib.h +++ b/lib/birdlib.h @@ -68,6 +68,38 @@ typedef s64 btime; #endif +/* Rate limiting */ + +struct tbf { + bird_clock_t timestamp; /* Last update */ + u16 count; /* Available tokens */ + u16 burst; /* Max number of tokens */ + u16 rate; /* Rate of replenishment */ + u16 mark; /* Whether last op was limited */ +}; + +/* Default TBF values for rate limiting log messages */ +#define TBF_DEFAULT_LOG_LIMITS { .rate = 1, .burst = 5 } + +void tbf_update(struct tbf *f); + +static inline int +tbf_limit(struct tbf *f) +{ + tbf_update(f); + + if (!f->count) + { + f->mark = 1; + return 1; + } + + f->count--; + f->mark = 0; + return 0; +} + + /* Logging and dying */ typedef struct buffer { @@ -88,16 +120,10 @@ typedef struct buffer { #define LOG_BUFFER_SIZE 1024 - -struct rate_limit { - bird_clock_t timestamp; - int count; -}; - #define log log_msg void log_commit(int class, buffer *buf); void log_msg(char *msg, ...); -void log_rl(struct rate_limit *rl, char *msg, ...); +void log_rl(struct tbf *rl, char *msg, ...); void die(char *msg, ...) NORET; void bug(char *msg, ...) NORET; diff --git a/lib/tbf.c b/lib/tbf.c new file mode 100644 index 00000000..39e18e57 --- /dev/null +++ b/lib/tbf.c @@ -0,0 +1,29 @@ +/* + * BIRD Library -- Token Bucket Filter + * + * (c) 2014 Ondrej Zajicek <santiago@crfreenet.org> + * (c) 2014 CZ.NIC z.s.p.o. + * + * Can be freely distributed and used under the terms of the GNU GPL. + */ + +#include "nest/bird.h" + +void +tbf_update(struct tbf *f) +{ + bird_clock_t delta = now - f->timestamp; + + if (delta == 0) + return; + + f->timestamp = now; + + if ((0 < delta) && (delta < f->burst)) + { + u32 next = f->count + delta * f->rate; + f->count = MIN(next, f->burst); + } + else + f->count = f->burst; +} |