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 atomic_sub(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 = (struct atmsvc_msg *)skb_put(skb, sizeof(struct atmsvc_msg)); 154 memset(msg, 0, sizeof(*msg)); 155 msg->type = type; 156 *(struct atm_vcc **) &msg->vcc = vcc; 157 *(struct atm_vcc **) &msg->listen_vcc = listen_vcc; 158 msg->reply = reply; 159 if (qos) 160 msg->qos = *qos; 161 if (vcc) 162 msg->sap = vcc->sap; 163 if (svc) 164 msg->svc = *svc; 165 if (vcc) 166 msg->local = vcc->local; 167 if (pvc) 168 msg->pvc = *pvc; 169 if (vcc) { 170 if (type == as_connect && test_bit(ATM_VF_SESSION, &vcc->flags)) 171 msg->session = ++session; 172 /* every new pmp connect gets the next session number */ 173 } 174 sigd_put_skb(skb); 175 if (vcc) 176 set_bit(ATM_VF_REGIS, &vcc->flags); 177 } 178 179 void sigd_enq(struct atm_vcc *vcc, enum atmsvc_msg_type type, 180 struct atm_vcc *listen_vcc, const struct sockaddr_atmpvc *pvc, 181 const struct sockaddr_atmsvc *svc) 182 { 183 sigd_enq2(vcc, type, listen_vcc, pvc, svc, vcc ? &vcc->qos : NULL, 0); 184 /* other ISP applications may use "reply" */ 185 } 186 187 static void purge_vcc(struct atm_vcc *vcc) 188 { 189 if (sk_atm(vcc)->sk_family == PF_ATMSVC && 190 !test_bit(ATM_VF_META, &vcc->flags)) { 191 set_bit(ATM_VF_RELEASED, &vcc->flags); 192 clear_bit(ATM_VF_REGIS, &vcc->flags); 193 vcc_release_async(vcc, -EUNATCH); 194 } 195 } 196 197 static void sigd_close(struct atm_vcc *vcc) 198 { 199 struct sock *s; 200 int i; 201 202 pr_debug("\n"); 203 sigd = NULL; 204 if (skb_peek(&sk_atm(vcc)->sk_receive_queue)) 205 pr_err("closing with requests pending\n"); 206 skb_queue_purge(&sk_atm(vcc)->sk_receive_queue); 207 208 read_lock(&vcc_sklist_lock); 209 for (i = 0; i < VCC_HTABLE_SIZE; ++i) { 210 struct hlist_head *head = &vcc_hash[i]; 211 212 sk_for_each(s, head) { 213 vcc = atm_sk(s); 214 215 purge_vcc(vcc); 216 } 217 } 218 read_unlock(&vcc_sklist_lock); 219 } 220 221 static struct atmdev_ops sigd_dev_ops = { 222 .close = sigd_close, 223 .send = sigd_send 224 }; 225 226 static struct atm_dev sigd_dev = { 227 .ops = &sigd_dev_ops, 228 .type = "sig", 229 .number = 999, 230 .lock = __SPIN_LOCK_UNLOCKED(sigd_dev.lock) 231 }; 232 233 int sigd_attach(struct atm_vcc *vcc) 234 { 235 if (sigd) 236 return -EADDRINUSE; 237 pr_debug("\n"); 238 sigd = vcc; 239 vcc->dev = &sigd_dev; 240 vcc_insert_socket(sk_atm(vcc)); 241 set_bit(ATM_VF_META, &vcc->flags); 242 set_bit(ATM_VF_READY, &vcc->flags); 243 return 0; 244 } 245