1 /* net/atm/signaling.c - ATM signaling */ 2 3 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */ 4 5 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__ 6 7 #include <linux/errno.h> /* error codes */ 8 #include <linux/kernel.h> /* printk */ 9 #include <linux/skbuff.h> 10 #include <linux/wait.h> 11 #include <linux/sched.h> /* jiffies and HZ */ 12 #include <linux/atm.h> /* ATM stuff */ 13 #include <linux/atmsap.h> 14 #include <linux/atmsvc.h> 15 #include <linux/atmdev.h> 16 #include <linux/bitops.h> 17 #include <linux/slab.h> 18 19 #include "resources.h" 20 #include "signaling.h" 21 22 struct atm_vcc *sigd = NULL; 23 24 static void sigd_put_skb(struct sk_buff *skb) 25 { 26 if (!sigd) { 27 pr_debug("atmsvc: no signaling daemon\n"); 28 kfree_skb(skb); 29 return; 30 } 31 atm_force_charge(sigd, skb->truesize); 32 skb_queue_tail(&sk_atm(sigd)->sk_receive_queue, skb); 33 sk_atm(sigd)->sk_data_ready(sk_atm(sigd)); 34 } 35 36 static void modify_qos(struct atm_vcc *vcc, struct atmsvc_msg *msg) 37 { 38 struct sk_buff *skb; 39 40 if (test_bit(ATM_VF_RELEASED, &vcc->flags) || 41 !test_bit(ATM_VF_READY, &vcc->flags)) 42 return; 43 msg->type = as_error; 44 if (!vcc->dev->ops->change_qos) 45 msg->reply = -EOPNOTSUPP; 46 else { 47 /* should lock VCC */ 48 msg->reply = vcc->dev->ops->change_qos(vcc, &msg->qos, 49 msg->reply); 50 if (!msg->reply) 51 msg->type = as_okay; 52 } 53 /* 54 * Should probably just turn around the old skb. But the, the buffer 55 * space accounting needs to follow the change too. Maybe later. 56 */ 57 while (!(skb = alloc_skb(sizeof(struct atmsvc_msg), GFP_KERNEL))) 58 schedule(); 59 *(struct atmsvc_msg *)skb_put(skb, sizeof(struct atmsvc_msg)) = *msg; 60 sigd_put_skb(skb); 61 } 62 63 static int sigd_send(struct atm_vcc *vcc, struct sk_buff *skb) 64 { 65 struct atmsvc_msg *msg; 66 struct atm_vcc *session_vcc; 67 struct sock *sk; 68 69 msg = (struct atmsvc_msg *) skb->data; 70 WARN_ON(refcount_sub_and_test(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc)); 71 vcc = *(struct atm_vcc **) &msg->vcc; 72 pr_debug("%d (0x%lx)\n", (int)msg->type, (unsigned long)vcc); 73 sk = sk_atm(vcc); 74 75 switch (msg->type) { 76 case as_okay: 77 sk->sk_err = -msg->reply; 78 clear_bit(ATM_VF_WAITING, &vcc->flags); 79 if (!*vcc->local.sas_addr.prv && !*vcc->local.sas_addr.pub) { 80 vcc->local.sas_family = AF_ATMSVC; 81 memcpy(vcc->local.sas_addr.prv, 82 msg->local.sas_addr.prv, ATM_ESA_LEN); 83 memcpy(vcc->local.sas_addr.pub, 84 msg->local.sas_addr.pub, ATM_E164_LEN + 1); 85 } 86 session_vcc = vcc->session ? vcc->session : vcc; 87 if (session_vcc->vpi || session_vcc->vci) 88 break; 89 session_vcc->itf = msg->pvc.sap_addr.itf; 90 session_vcc->vpi = msg->pvc.sap_addr.vpi; 91 session_vcc->vci = msg->pvc.sap_addr.vci; 92 if (session_vcc->vpi || session_vcc->vci) 93 session_vcc->qos = msg->qos; 94 break; 95 case as_error: 96 clear_bit(ATM_VF_REGIS, &vcc->flags); 97 clear_bit(ATM_VF_READY, &vcc->flags); 98 sk->sk_err = -msg->reply; 99 clear_bit(ATM_VF_WAITING, &vcc->flags); 100 break; 101 case as_indicate: 102 vcc = *(struct atm_vcc **)&msg->listen_vcc; 103 sk = sk_atm(vcc); 104 pr_debug("as_indicate!!!\n"); 105 lock_sock(sk); 106 if (sk_acceptq_is_full(sk)) { 107 sigd_enq(NULL, as_reject, vcc, NULL, NULL); 108 dev_kfree_skb(skb); 109 goto as_indicate_complete; 110 } 111 sk->sk_ack_backlog++; 112 skb_queue_tail(&sk->sk_receive_queue, skb); 113 pr_debug("waking sk_sleep(sk) 0x%p\n", sk_sleep(sk)); 114 sk->sk_state_change(sk); 115 as_indicate_complete: 116 release_sock(sk); 117 return 0; 118 case as_close: 119 set_bit(ATM_VF_RELEASED, &vcc->flags); 120 vcc_release_async(vcc, msg->reply); 121 goto out; 122 case as_modify: 123 modify_qos(vcc, msg); 124 break; 125 case as_addparty: 126 case as_dropparty: 127 sk->sk_err_soft = -msg->reply; 128 /* < 0 failure, otherwise ep_ref */ 129 clear_bit(ATM_VF_WAITING, &vcc->flags); 130 break; 131 default: 132 pr_alert("bad message type %d\n", (int)msg->type); 133 return -EINVAL; 134 } 135 sk->sk_state_change(sk); 136 out: 137 dev_kfree_skb(skb); 138 return 0; 139 } 140 141 void sigd_enq2(struct atm_vcc *vcc, enum atmsvc_msg_type type, 142 struct atm_vcc *listen_vcc, const struct sockaddr_atmpvc *pvc, 143 const struct sockaddr_atmsvc *svc, const struct atm_qos *qos, 144 int reply) 145 { 146 struct sk_buff *skb; 147 struct atmsvc_msg *msg; 148 static unsigned int session = 0; 149 150 pr_debug("%d (0x%p)\n", (int)type, vcc); 151 while (!(skb = alloc_skb(sizeof(struct atmsvc_msg), GFP_KERNEL))) 152 schedule(); 153 msg = skb_put_zero(skb, sizeof(struct atmsvc_msg)); 154 msg->type = type; 155 *(struct atm_vcc **) &msg->vcc = vcc; 156 *(struct atm_vcc **) &msg->listen_vcc = listen_vcc; 157 msg->reply = reply; 158 if (qos) 159 msg->qos = *qos; 160 if (vcc) 161 msg->sap = vcc->sap; 162 if (svc) 163 msg->svc = *svc; 164 if (vcc) 165 msg->local = vcc->local; 166 if (pvc) 167 msg->pvc = *pvc; 168 if (vcc) { 169 if (type == as_connect && test_bit(ATM_VF_SESSION, &vcc->flags)) 170 msg->session = ++session; 171 /* every new pmp connect gets the next session number */ 172 } 173 sigd_put_skb(skb); 174 if (vcc) 175 set_bit(ATM_VF_REGIS, &vcc->flags); 176 } 177 178 void sigd_enq(struct atm_vcc *vcc, enum atmsvc_msg_type type, 179 struct atm_vcc *listen_vcc, const struct sockaddr_atmpvc *pvc, 180 const struct sockaddr_atmsvc *svc) 181 { 182 sigd_enq2(vcc, type, listen_vcc, pvc, svc, vcc ? &vcc->qos : NULL, 0); 183 /* other ISP applications may use "reply" */ 184 } 185 186 static void purge_vcc(struct atm_vcc *vcc) 187 { 188 if (sk_atm(vcc)->sk_family == PF_ATMSVC && 189 !test_bit(ATM_VF_META, &vcc->flags)) { 190 set_bit(ATM_VF_RELEASED, &vcc->flags); 191 clear_bit(ATM_VF_REGIS, &vcc->flags); 192 vcc_release_async(vcc, -EUNATCH); 193 } 194 } 195 196 static void sigd_close(struct atm_vcc *vcc) 197 { 198 struct sock *s; 199 int i; 200 201 pr_debug("\n"); 202 sigd = NULL; 203 if (skb_peek(&sk_atm(vcc)->sk_receive_queue)) 204 pr_err("closing with requests pending\n"); 205 skb_queue_purge(&sk_atm(vcc)->sk_receive_queue); 206 207 read_lock(&vcc_sklist_lock); 208 for (i = 0; i < VCC_HTABLE_SIZE; ++i) { 209 struct hlist_head *head = &vcc_hash[i]; 210 211 sk_for_each(s, head) { 212 vcc = atm_sk(s); 213 214 purge_vcc(vcc); 215 } 216 } 217 read_unlock(&vcc_sklist_lock); 218 } 219 220 static const struct atmdev_ops sigd_dev_ops = { 221 .close = sigd_close, 222 .send = sigd_send 223 }; 224 225 static struct atm_dev sigd_dev = { 226 .ops = &sigd_dev_ops, 227 .type = "sig", 228 .number = 999, 229 .lock = __SPIN_LOCK_UNLOCKED(sigd_dev.lock) 230 }; 231 232 int sigd_attach(struct atm_vcc *vcc) 233 { 234 if (sigd) 235 return -EADDRINUSE; 236 pr_debug("\n"); 237 sigd = vcc; 238 vcc->dev = &sigd_dev; 239 vcc_insert_socket(sk_atm(vcc)); 240 set_bit(ATM_VF_META, &vcc->flags); 241 set_bit(ATM_VF_READY, &vcc->flags); 242 return 0; 243 } 244