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  *      This is called from atm_ioctl only. You must hold the lock as a caller
  57  */
  58
  59 void atm_reset_addr(struct atm_dev *dev)
  60 {
  61         struct atm_dev_addr *this;
  62
  63         down(&local_lock);
  64         while (dev->local) {
  65                 this = dev->local;
  66                 dev->local = this->next;
  67                 kfree(this);
  68         }
  69         up(&local_lock);
  70         notify_sigd(dev);
  71 }
  72
  73
  74 int atm_add_addr(struct atm_dev *dev,struct sockaddr_atmsvc *addr)
  75 {
  76         struct atm_dev_addr **walk;
  77         int error;
  78
  79         error = check_addr(addr);
  80         if (error) return error;
  81         down(&local_lock);
  82         for (walk = &dev->local; *walk; walk = &(*walk)->next)
  83                 if (identical(&(*walk)->addr,addr)) {
  84                         up(&local_lock);
  85                         return -EEXIST;
  86                 }
  87         *walk = kmalloc(sizeof(struct atm_dev_addr),GFP_KERNEL);
  88         if (!*walk) {
  89                 up(&local_lock);
  90                 return -ENOMEM;
  91         }
  92         (*walk)->addr = *addr;
  93         (*walk)->next = NULL;
  94         up(&local_lock);
  95         notify_sigd(dev);
  96         return 0;
  97 }
  98
  99
 100 int atm_del_addr(struct atm_dev *dev,struct sockaddr_atmsvc *addr)
 101 {
 102         struct atm_dev_addr **walk,*this;
 103         int error;
 104
 105         error = check_addr(addr);
 106         if (error) return error;
 107         down(&local_lock);
 108         for (walk = &dev->local; *walk; walk = &(*walk)->next)
 109                 if (identical(&(*walk)->addr,addr)) break;
 110         if (!*walk) {
 111                 up(&local_lock);
 112                 return -ENOENT;
 113         }
 114         this = *walk;
 115         *walk = this->next;
 116         kfree(this);
 117         up(&local_lock);
 118         notify_sigd(dev);
 119         return 0;
 120 }
 121
 122
 123 int atm_get_addr(struct atm_dev *dev,struct sockaddr_atmsvc *u_buf,int size)
 124 {
 125         struct atm_dev_addr *walk;
 126         int total;
 127
 128         down(&local_lock);
 129         total = 0;
 130         for (walk = dev->local; walk; walk = walk->next) {
 131                 total += sizeof(struct sockaddr_atmsvc);
 132                 if (total > size) {
 133                         up(&local_lock);
 134                         return -E2BIG;
 135                 }
 136                 if (copy_to_user(u_buf,&walk->addr,
 137                     sizeof(struct sockaddr_atmsvc))) {
 138                         up(&local_lock);
 139                         return -EFAULT;
 140                 }
 141                 u_buf++;
 142         }
 143         up(&local_lock);
 144         return total;
 145 }