net/atm/addr.c

   1 /* net/atm/addr.c - Local ATM address registry */
   2
   3 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
   4
   5
   6 #include <linux/atm.h>
   7 #include <linux/atmdev.h>
   8 #include <linux/sched.h>
   9 #include <asm/uaccess.h>
  10
  11 #include "signaling.h"
  12 #include "addr.h"
  13
  14
  15 static int check_addr(struct sockaddr_atmsvc *addr)
  16 {
  17         int i;
  18
  19         if (addr->sas_family != AF_ATMSVC) return -EAFNOSUPPORT;
  20         if (!*addr->sas_addr.pub)
  21                 return *addr->sas_addr.prv ? 0 : -EINVAL;
  22         for (i = 1; i < ATM_E164_LEN+1; i++) /* make sure it's \0-terminated */
  23                 if (!addr->sas_addr.pub[i]) return 0;
  24         return -EINVAL;
  25 }
  26
  27
  28 static int identical(struct sockaddr_atmsvc *a,struct sockaddr_atmsvc *b)
  29 {
  30         if (*a->sas_addr.prv)
  31                 if (memcmp(a->sas_addr.prv,b->sas_addr.prv,ATM_ESA_LEN))
  32                         return 0;
  33         if (!*a->sas_addr.pub) return !*b->sas_addr.pub;
  34         if (!*b->sas_addr.pub) return 0;
  35         return !strcmp(a->sas_addr.pub,b->sas_addr.pub);
  36 }
  37
  38
  39 /*
  40  * Avoid modification of any list of local interfaces while reading it
  41  * (which may involve page faults and therefore rescheduling)
  42  */
  43
  44 static DECLARE_MUTEX(local_lock);
  45 extern  spinlock_t atm_dev_lock;
  46
  47 static void notify_sigd(struct atm_dev *dev)
  48 {
  49         struct sockaddr_atmpvc pvc;
  50
  51         pvc.sap_addr.itf = dev->number;
  52         sigd_enq(NULL,as_itf_notify,NULL,&pvc,NULL);
  53 }
  54
  55
  56 void reset_addr(struct atm_dev *dev)
  57 {
  58         struct atm_dev_addr *this;
  59
  60         down(&local_lock);
  61         spin_lock (&atm_dev_lock);
  62         while (dev->local) {
  63                 this = dev->local;
  64                 dev->local = this->next;
  65                 kfree(this);
  66         }
  67         up(&local_lock);
  68         spin_unlock (&atm_dev_lock);
  69         notify_sigd(dev);
  70 }
  71
  72
  73 int add_addr(struct atm_dev *dev,struct sockaddr_atmsvc *addr)
  74 {
  75         struct atm_dev_addr **walk;
  76         int error;
  77
  78         error = check_addr(addr);
  79         if (error) return error;
  80         down(&local_lock);
  81         for (walk = &dev->local; *walk; walk = &(*walk)->next)
  82                 if (identical(&(*walk)->addr,addr)) {
  83                         up(&local_lock);
  84                         return -EEXIST;
  85                 }
  86         *walk = kmalloc(sizeof(struct atm_dev_addr),GFP_KERNEL);
  87         if (!*walk) {
  88                 up(&local_lock);
  89                 return -ENOMEM;
  90         }
  91         (*walk)->addr = *addr;
  92         (*walk)->next = NULL;
  93         up(&local_lock);
  94         notify_sigd(dev);
  95         return 0;
  96 }
  97
  98
  99 int del_addr(struct atm_dev *dev,struct sockaddr_atmsvc *addr)
 100 {
 101         struct atm_dev_addr **walk,*this;
 102         int error;
 103
 104         error = check_addr(addr);
 105         if (error) return error;
 106         down(&local_lock);
 107         for (walk = &dev->local; *walk; walk = &(*walk)->next)
 108                 if (identical(&(*walk)->addr,addr)) break;
 109         if (!*walk) {
 110                 up(&local_lock);
 111                 return -ENOENT;
 112         }
 113         this = *walk;
 114         *walk = this->next;
 115         kfree(this);
 116         up(&local_lock);
 117         notify_sigd(dev);
 118         return 0;
 119 }
 120
 121
 122 int get_addr(struct atm_dev *dev,struct sockaddr_atmsvc *u_buf,int size)
 123 {
 124         struct atm_dev_addr *walk;
 125         int total;
 126
 127         down(&local_lock);
 128         total = 0;
 129         for (walk = dev->local; walk; walk = walk->next) {
 130                 total += sizeof(struct sockaddr_atmsvc);
 131                 if (total > size) {
 132                         up(&local_lock);
 133                         return -E2BIG;
 134                 }
 135                 if (copy_to_user(u_buf,&walk->addr,
 136                     sizeof(struct sockaddr_atmsvc))) {
 137                         up(&local_lock);
 138                         return -EFAULT;
 139                 }
 140                 u_buf++;
 141         }
 142         up(&local_lock);
 143         return total;
 144 }