rl.c

   1 // L2TPNS Rate Limiting Stuff
   2 // $Id: rl.c,v 1.4 2004/05/24 04:28:41 fred_nerk Exp $
   3
   4 #include <arpa/inet.h>
   5 #include <errno.h>
   6 #include <malloc.h>
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <string.h>
  10 #include <sys/file.h>
  11 #include <sys/stat.h>
  12 #include <sys/types.h>
  13 #include <sys/wait.h>
  14 #include <time.h>
  15 #include <unistd.h>
  16 #include "l2tpns.h"
  17
  18 extern radiust *radius;
  19 extern sessiont *session;
  20 extern u32 sessionid;
  21 extern tbft *filter_buckets;
  22 extern struct configt *config;
  23
  24 #define DEVICE "tun0"
  25
  26 void init_rl()
  27 {
  28     char *commands[] = {
  29         "tc qdisc add dev " DEVICE " root handle 1: htb",
  30         "tc filter del dev " DEVICE " protocol ip pref 1 fw",
  31         "iptables -t mangle -N throttle 2>&1 >/dev/null",
  32         "iptables -t mangle -F throttle 2>&1 >/dev/null",
  33         "iptables -t mangle -A l2tpns -j throttle 2>&1 >/dev/null",
  34         NULL
  35     };
  36     int i;
  37
  38     log(2, 0, 0, 0, "Initializing HTB\n");
  39     for (i = 0; commands[i] && *commands[i]; i++)
  40     {
  41         log(3, 0, 0, 0, "Running \"%s\"\n", commands[i]);
  42         system(commands[i]);
  43     }
  44     log(2, 0, 0, 0, "Done initializing HTB\n");
  45 }
  46
  47 u16 rl_create_tbf()
  48 {
  49     u16 t;
  50     char cmd[2048];
  51     if (!config->rl_rate) return 0;
  52
  53     t = ++config->next_tbf;
  54     if (config->next_tbf >= MAXSESSION) return 0;
  55     snprintf(filter_buckets[t].handle, 9, "1:%d0", t);
  56
  57     log(2, 0, 0, 0, "Creating new htb %s\n", filter_buckets[t].handle);
  58     snprintf(cmd, 2048, "tc class add dev " DEVICE " parent 1: classid %s htb rate %lukbit burst 15k",
  59             filter_buckets[t].handle, config->rl_rate);
  60     log(3, 0, 0, 0, "%s\n", cmd);
  61     if (WEXITSTATUS(system(cmd)) != 0)
  62     {
  63         memset(filter_buckets[t].handle, 0, sizeof(filter_buckets[t].handle));
  64         log(0, 0, 0, 0, "tc returned an error creating a token bucket\n");
  65         return 0;
  66     }
  67
  68     snprintf(cmd, 2048, "tc filter add dev " DEVICE " protocol ip parent 1:0 prio 1 handle %d fw flowid %s",
  69             t, filter_buckets[t].handle);
  70     log(3, 0, 0, 0, "%s\n", cmd);
  71     if (WEXITSTATUS(system(cmd)) != 0)
  72     {
  73         memset(filter_buckets[t].handle, 0, sizeof(filter_buckets[t].handle));
  74         log(0, 0, 0, 0, "tc returned an error creating a filter\n");
  75         return 0;
  76     }
  77
  78     return t;
  79 }
  80
  81 u16 rl_get_tbf()
  82 {
  83     int i;
  84     if (!config->rl_rate) return 0;
  85
  86     for (i = 1; i < MAXSESSION; i++)
  87     {
  88         if (!*filter_buckets[i].handle) continue;
  89         if (filter_buckets[i].in_use) continue;
  90
  91         filter_buckets[i].in_use = 1;
  92         log(2, 0, 0, 0, "Returning tbf %s\n", filter_buckets[i].handle);
  93         return i;
  94     }
  95     i = rl_create_tbf();
  96     if (i) filter_buckets[i].in_use = 1;
  97     return i;
  98 }
  99
 100 void rl_done_tbf(u16 t)
 101 {
 102     if (!t) return;
 103     log(2, 0, 0, 0, "Freeing up HTB %s\n", filter_buckets[t].handle);
 104     filter_buckets[t].in_use = 0;
 105 }
 106
 107 void rl_destroy_tbf(u16 t)
 108 {
 109     char cmd[2048];
 110     if (!config->rl_rate) return;
 111     if (filter_buckets[t].in_use)
 112     {
 113         log(0, 0, 0, 0, "Trying to destroy an in-use HTB %s\n", filter_buckets[t].handle);
 114         return;
 115     }
 116     snprintf(cmd, 2048, "tc qdisc del dev " DEVICE " handle %s", filter_buckets[t].handle);
 117     if (WEXITSTATUS(system(cmd)) != 0)
 118         log(0, 0, 0, 0, "tc returned an error deleting a token bucket\n");
 119     memset(filter_buckets[t].handle, 0, sizeof(filter_buckets[t].handle));
 120 }
 121