1/* 2 * q_red.c RED. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 10 * 11 */ 12 13#include <stdio.h> 14#include <stdlib.h> 15#include <unistd.h> 16#include <syslog.h> 17#include <fcntl.h> 18#include <sys/socket.h> 19#include <netinet/in.h> 20#include <arpa/inet.h> 21#include <string.h> 22 23#include "utils.h" 24#include "tc_util.h" 25 26#include "tc_red.h" 27 28static void explain(void) 29{ 30 fprintf(stderr, "Usage: ... red limit BYTES min BYTES max BYTES avpkt BYTES burst PACKETS\n"); 31 fprintf(stderr, " probability PROBABILITY bandwidth KBPS [ ecn ]\n"); 32} 33 34static int red_parse_opt(struct qdisc_util *qu, int argc, char **argv, struct nlmsghdr *n) 35{ 36 struct tc_red_qopt opt; 37 unsigned burst = 0; 38 unsigned avpkt = 0; 39 double probability = 0.02; 40 unsigned rate = 0; 41 int ecn_ok = 0; 42 int wlog; 43 __u8 sbuf[256]; 44 struct rtattr *tail; 45 46 memset(&opt, 0, sizeof(opt)); 47 48 while (argc > 0) { 49 if (strcmp(*argv, "limit") == 0) { 50 NEXT_ARG(); 51 if (get_size(&opt.limit, *argv)) { 52 fprintf(stderr, "Illegal \"limit\"\n"); 53 return -1; 54 } 55 } else if (strcmp(*argv, "min") == 0) { 56 NEXT_ARG(); 57 if (get_size(&opt.qth_min, *argv)) { 58 fprintf(stderr, "Illegal \"min\"\n"); 59 return -1; 60 } 61 } else if (strcmp(*argv, "max") == 0) { 62 NEXT_ARG(); 63 if (get_size(&opt.qth_max, *argv)) { 64 fprintf(stderr, "Illegal \"max\"\n"); 65 return -1; 66 } 67 } else if (strcmp(*argv, "burst") == 0) { 68 NEXT_ARG(); 69 if (get_unsigned(&burst, *argv, 0)) { 70 fprintf(stderr, "Illegal \"burst\"\n"); 71 return -1; 72 } 73 } else if (strcmp(*argv, "avpkt") == 0) { 74 NEXT_ARG(); 75 if (get_size(&avpkt, *argv)) { 76 fprintf(stderr, "Illegal \"avpkt\"\n"); 77 return -1; 78 } 79 } else if (strcmp(*argv, "probability") == 0) { 80 NEXT_ARG(); 81 if (sscanf(*argv, "%lg", &probability) != 1) { 82 fprintf(stderr, "Illegal \"probability\"\n"); 83 return -1; 84 } 85 } else if (strcmp(*argv, "bandwidth") == 0) { 86 NEXT_ARG(); 87 if (get_rate(&rate, *argv)) { 88 fprintf(stderr, "Illegal \"bandwidth\"\n"); 89 return -1; 90 } 91 } else if (strcmp(*argv, "ecn") == 0) { 92 ecn_ok = 1; 93 } else if (strcmp(*argv, "help") == 0) { 94 explain(); 95 return -1; 96 } else { 97 fprintf(stderr, "What is \"%s\"?\n", *argv); 98 explain(); 99 return -1; 100 } 101 argc--; argv++; 102 } 103 104 if (rate == 0) 105 get_rate(&rate, "10Mbit"); 106 107 if (!opt.qth_min || !opt.qth_max || !burst || !opt.limit || !avpkt) { 108 fprintf(stderr, "Required parameter (min, max, burst, limit, avpkt) is missing\n"); 109 return -1; 110 } 111 112 if ((wlog = tc_red_eval_ewma(opt.qth_min, burst, avpkt)) < 0) { 113 fprintf(stderr, "RED: failed to calculate EWMA constant.\n"); 114 return -1; 115 } 116 if (wlog >= 10) 117 fprintf(stderr, "RED: WARNING. Burst %d seems to be to large.\n", burst); 118 opt.Wlog = wlog; 119 if ((wlog = tc_red_eval_P(opt.qth_min, opt.qth_max, probability)) < 0) { 120 fprintf(stderr, "RED: failed to calculate probability.\n"); 121 return -1; 122 } 123 opt.Plog = wlog; 124 if ((wlog = tc_red_eval_idle_damping(opt.Wlog, avpkt, rate, sbuf)) < 0) { 125 fprintf(stderr, "RED: failed to calculate idle damping table.\n"); 126 return -1; 127 } 128 opt.Scell_log = wlog; 129 if (ecn_ok) { 130#ifdef TC_RED_ECN 131 opt.flags |= TC_RED_ECN; 132#else 133 fprintf(stderr, "RED: ECN support is missing in this binary.\n"); 134 return -1; 135#endif 136 } 137 138 tail = NLMSG_TAIL(n); 139 addattr_l(n, 1024, TCA_OPTIONS, NULL, 0); 140 addattr_l(n, 1024, TCA_RED_PARMS, &opt, sizeof(opt)); 141 addattr_l(n, 1024, TCA_RED_STAB, sbuf, 256); 142 tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail; 143 return 0; 144} 145 146static int red_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt) 147{ 148 struct rtattr *tb[TCA_RED_STAB+1]; 149 struct tc_red_qopt *qopt; 150 SPRINT_BUF(b1); 151 SPRINT_BUF(b2); 152 SPRINT_BUF(b3); 153 154 if (opt == NULL) 155 return 0; 156 157 parse_rtattr_nested(tb, TCA_RED_STAB, opt); 158 159 if (tb[TCA_RED_PARMS] == NULL) 160 return -1; 161 qopt = RTA_DATA(tb[TCA_RED_PARMS]); 162 if (RTA_PAYLOAD(tb[TCA_RED_PARMS]) < sizeof(*qopt)) 163 return -1; 164 fprintf(f, "limit %s min %s max %s ", 165 sprint_size(qopt->limit, b1), 166 sprint_size(qopt->qth_min, b2), 167 sprint_size(qopt->qth_max, b3)); 168#ifdef TC_RED_ECN 169 if (qopt->flags & TC_RED_ECN) 170 fprintf(f, "ecn "); 171#endif 172 if (show_details) { 173 fprintf(f, "ewma %u Plog %u Scell_log %u", 174 qopt->Wlog, qopt->Plog, qopt->Scell_log); 175 } 176 return 0; 177} 178 179static int red_print_xstats(struct qdisc_util *qu, FILE *f, struct rtattr *xstats) 180{ 181#ifdef TC_RED_ECN 182 struct tc_red_xstats *st; 183 184 if (xstats == NULL) 185 return 0; 186 187 if (RTA_PAYLOAD(xstats) < sizeof(*st)) 188 return -1; 189 190 st = RTA_DATA(xstats); 191 fprintf(f, " marked %u early %u pdrop %u other %u", 192 st->marked, st->early, st->pdrop, st->other); 193 return 0; 194 195#endif 196 return 0; 197} 198 199 200struct qdisc_util red_qdisc_util = { 201 .id = "red", 202 .parse_qopt = red_parse_opt, 203 .print_qopt = red_print_opt, 204 .print_xstats = red_print_xstats, 205}; 206