1 /* 2 * net/sched/act_gact.c Generic actions 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 * copyright Jamal Hadi Salim (2002-4) 10 * 11 */ 12 13 #include <linux/types.h> 14 #include <linux/kernel.h> 15 #include <linux/string.h> 16 #include <linux/errno.h> 17 #include <linux/skbuff.h> 18 #include <linux/rtnetlink.h> 19 #include <linux/module.h> 20 #include <linux/init.h> 21 #include <net/netlink.h> 22 #include <net/pkt_sched.h> 23 #include <linux/tc_act/tc_gact.h> 24 #include <net/tc_act/tc_gact.h> 25 26 #define GACT_TAB_MASK 15 27 28 #ifdef CONFIG_GACT_PROB 29 static int gact_net_rand(struct tcf_gact *gact) 30 { 31 if (!gact->tcfg_pval || prandom_u32() % gact->tcfg_pval) 32 return gact->tcf_action; 33 return gact->tcfg_paction; 34 } 35 36 static int gact_determ(struct tcf_gact *gact) 37 { 38 if (!gact->tcfg_pval || gact->tcf_bstats.packets % gact->tcfg_pval) 39 return gact->tcf_action; 40 return gact->tcfg_paction; 41 } 42 43 typedef int (*g_rand)(struct tcf_gact *gact); 44 static g_rand gact_rand[MAX_RAND] = { NULL, gact_net_rand, gact_determ }; 45 #endif /* CONFIG_GACT_PROB */ 46 47 static const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = { 48 [TCA_GACT_PARMS] = { .len = sizeof(struct tc_gact) }, 49 [TCA_GACT_PROB] = { .len = sizeof(struct tc_gact_p) }, 50 }; 51 52 static int tcf_gact_init(struct net *net, struct nlattr *nla, 53 struct nlattr *est, struct tc_action *a, 54 int ovr, int bind) 55 { 56 struct nlattr *tb[TCA_GACT_MAX + 1]; 57 struct tc_gact *parm; 58 struct tcf_gact *gact; 59 int ret = 0; 60 int err; 61 #ifdef CONFIG_GACT_PROB 62 struct tc_gact_p *p_parm = NULL; 63 #endif 64 65 if (nla == NULL) 66 return -EINVAL; 67 68 err = nla_parse_nested(tb, TCA_GACT_MAX, nla, gact_policy); 69 if (err < 0) 70 return err; 71 72 if (tb[TCA_GACT_PARMS] == NULL) 73 return -EINVAL; 74 parm = nla_data(tb[TCA_GACT_PARMS]); 75 76 #ifndef CONFIG_GACT_PROB 77 if (tb[TCA_GACT_PROB] != NULL) 78 return -EOPNOTSUPP; 79 #else 80 if (tb[TCA_GACT_PROB]) { 81 p_parm = nla_data(tb[TCA_GACT_PROB]); 82 if (p_parm->ptype >= MAX_RAND) 83 return -EINVAL; 84 } 85 #endif 86 87 if (!tcf_hash_check(parm->index, a, bind)) { 88 ret = tcf_hash_create(parm->index, est, a, sizeof(*gact), bind); 89 if (ret) 90 return ret; 91 ret = ACT_P_CREATED; 92 } else { 93 if (bind)/* dont override defaults */ 94 return 0; 95 tcf_hash_release(a, bind); 96 if (!ovr) 97 return -EEXIST; 98 } 99 100 gact = to_gact(a); 101 102 spin_lock_bh(&gact->tcf_lock); 103 gact->tcf_action = parm->action; 104 #ifdef CONFIG_GACT_PROB 105 if (p_parm) { 106 gact->tcfg_paction = p_parm->paction; 107 gact->tcfg_pval = p_parm->pval; 108 gact->tcfg_ptype = p_parm->ptype; 109 } 110 #endif 111 spin_unlock_bh(&gact->tcf_lock); 112 if (ret == ACT_P_CREATED) 113 tcf_hash_insert(a); 114 return ret; 115 } 116 117 static int tcf_gact(struct sk_buff *skb, const struct tc_action *a, 118 struct tcf_result *res) 119 { 120 struct tcf_gact *gact = a->priv; 121 int action = TC_ACT_SHOT; 122 123 spin_lock(&gact->tcf_lock); 124 #ifdef CONFIG_GACT_PROB 125 if (gact->tcfg_ptype) 126 action = gact_rand[gact->tcfg_ptype](gact); 127 else 128 action = gact->tcf_action; 129 #else 130 action = gact->tcf_action; 131 #endif 132 gact->tcf_bstats.bytes += qdisc_pkt_len(skb); 133 gact->tcf_bstats.packets++; 134 if (action == TC_ACT_SHOT) 135 gact->tcf_qstats.drops++; 136 gact->tcf_tm.lastuse = jiffies; 137 spin_unlock(&gact->tcf_lock); 138 139 return action; 140 } 141 142 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref) 143 { 144 unsigned char *b = skb_tail_pointer(skb); 145 struct tcf_gact *gact = a->priv; 146 struct tc_gact opt = { 147 .index = gact->tcf_index, 148 .refcnt = gact->tcf_refcnt - ref, 149 .bindcnt = gact->tcf_bindcnt - bind, 150 .action = gact->tcf_action, 151 }; 152 struct tcf_t t; 153 154 if (nla_put(skb, TCA_GACT_PARMS, sizeof(opt), &opt)) 155 goto nla_put_failure; 156 #ifdef CONFIG_GACT_PROB 157 if (gact->tcfg_ptype) { 158 struct tc_gact_p p_opt = { 159 .paction = gact->tcfg_paction, 160 .pval = gact->tcfg_pval, 161 .ptype = gact->tcfg_ptype, 162 }; 163 164 if (nla_put(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt)) 165 goto nla_put_failure; 166 } 167 #endif 168 t.install = jiffies_to_clock_t(jiffies - gact->tcf_tm.install); 169 t.lastuse = jiffies_to_clock_t(jiffies - gact->tcf_tm.lastuse); 170 t.expires = jiffies_to_clock_t(gact->tcf_tm.expires); 171 if (nla_put(skb, TCA_GACT_TM, sizeof(t), &t)) 172 goto nla_put_failure; 173 return skb->len; 174 175 nla_put_failure: 176 nlmsg_trim(skb, b); 177 return -1; 178 } 179 180 static struct tc_action_ops act_gact_ops = { 181 .kind = "gact", 182 .type = TCA_ACT_GACT, 183 .owner = THIS_MODULE, 184 .act = tcf_gact, 185 .dump = tcf_gact_dump, 186 .init = tcf_gact_init, 187 }; 188 189 MODULE_AUTHOR("Jamal Hadi Salim(2002-4)"); 190 MODULE_DESCRIPTION("Generic Classifier actions"); 191 MODULE_LICENSE("GPL"); 192 193 static int __init gact_init_module(void) 194 { 195 #ifdef CONFIG_GACT_PROB 196 pr_info("GACT probability on\n"); 197 #else 198 pr_info("GACT probability NOT on\n"); 199 #endif 200 return tcf_register_action(&act_gact_ops, GACT_TAB_MASK); 201 } 202 203 static void __exit gact_cleanup_module(void) 204 { 205 tcf_unregister_action(&act_gact_ops); 206 } 207 208 module_init(gact_init_module); 209 module_exit(gact_cleanup_module); 210