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/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
*/
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <net/ax25.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <linux/uaccess.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/notifier.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/stat.h>
#include <linux/sysctl.h>
#include <linux/export.h>
#include <net/ip.h>
#include <net/arp.h>
/*
* Callsign/UID mapper. This is in kernel space for security on multi-amateur machines.
*/
static HLIST_HEAD(ax25_uid_list);
static DEFINE_RWLOCK(ax25_uid_lock);
int ax25_uid_policy;
EXPORT_SYMBOL(ax25_uid_policy);
ax25_uid_assoc *ax25_findbyuid(kuid_t uid)
{
ax25_uid_assoc *ax25_uid, *res = NULL;
read_lock(&ax25_uid_lock);
ax25_uid_for_each(ax25_uid, &ax25_uid_list) {
if (uid_eq(ax25_uid->uid, uid)) {
ax25_uid_hold(ax25_uid);
res = ax25_uid;
break;
}
}
read_unlock(&ax25_uid_lock);
return res;
}
EXPORT_SYMBOL(ax25_findbyuid);
int ax25_uid_ioctl(int cmd, struct sockaddr_ax25 *sax)
{
ax25_uid_assoc *ax25_uid;
ax25_uid_assoc *user;
unsigned long res;
switch (cmd) {
case SIOCAX25GETUID:
res = -ENOENT;
read_lock(&ax25_uid_lock);
ax25_uid_for_each(ax25_uid, &ax25_uid_list) {
if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0) {
res = from_kuid_munged(current_user_ns(), ax25_uid->uid);
break;
}
}
read_unlock(&ax25_uid_lock);
return res;
case SIOCAX25ADDUID:
{
kuid_t sax25_kuid;
if (!capable(CAP_NET_ADMIN))
return -EPERM;
sax25_kuid = make_kuid(current_user_ns(), sax->sax25_uid);
if (!uid_valid(sax25_kuid))
return -EINVAL;
user = ax25_findbyuid(sax25_kuid);
if (user) {
ax25_uid_put(user);
return -EEXIST;
}
if (sax->sax25_uid == 0)
return -EINVAL;
if ((ax25_uid = kmalloc(sizeof(*ax25_uid), GFP_KERNEL)) == NULL)
return -ENOMEM;
refcount_set(&ax25_uid->refcount, 1);
ax25_uid->uid = sax25_kuid;
ax25_uid->call = sax->sax25_call;
write_lock(&ax25_uid_lock);
hlist_add_head(&ax25_uid->uid_node, &ax25_uid_list);
write_unlock(&ax25_uid_lock);
return 0;
}
case SIOCAX25DELUID:
if (!capable(CAP_NET_ADMIN))
return -EPERM;
ax25_uid = NULL;
write_lock(&ax25_uid_lock);
ax25_uid_for_each(ax25_uid, &ax25_uid_list) {
if (ax25cmp(&sax->sax25_call, &ax25_uid->call) == 0)
break;
}
if (ax25_uid == NULL) {
write_unlock(&ax25_uid_lock);
return -ENOENT;
}
hlist_del_init(&ax25_uid->uid_node);
ax25_uid_put(ax25_uid);
write_unlock(&ax25_uid_lock);
return 0;
default:
return -EINVAL;
}
return -EINVAL; /*NOTREACHED */
}
#ifdef CONFIG_PROC_FS
static void *ax25_uid_seq_start(struct seq_file *seq, loff_t *pos)
__acquires(ax25_uid_lock)
{
read_lock(&ax25_uid_lock);
return seq_hlist_start_head(&ax25_uid_list, *pos);
}
static void *ax25_uid_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
return seq_hlist_next(v, &ax25_uid_list, pos);
}
static void ax25_uid_seq_stop(struct seq_file *seq, void *v)
__releases(ax25_uid_lock)
{
read_unlock(&ax25_uid_lock);
}
static int ax25_uid_seq_show(struct seq_file *seq, void *v)
{
char buf[11];
if (v == SEQ_START_TOKEN)
seq_printf(seq, "Policy: %d\n", ax25_uid_policy);
else {
struct ax25_uid_assoc *pt;
pt = hlist_entry(v, struct ax25_uid_assoc, uid_node);
seq_printf(seq, "%6d %s\n",
from_kuid_munged(seq_user_ns(seq), pt->uid),
ax2asc(buf, &pt->call));
}
return 0;
}
static const struct seq_operations ax25_uid_seqops = {
.start = ax25_uid_seq_start,
.next = ax25_uid_seq_next,
.stop = ax25_uid_seq_stop,
.show = ax25_uid_seq_show,
};
static int ax25_uid_info_open(struct inode *inode, struct file *file)
{
return seq_open(file, &ax25_uid_seqops);
}
const struct file_operations ax25_uid_fops = {
.open = ax25_uid_info_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
#endif
/*
* Free all memory associated with UID/Callsign structures.
*/
void __exit ax25_uid_free(void)
{
ax25_uid_assoc *ax25_uid;
write_lock(&ax25_uid_lock);
again:
ax25_uid_for_each(ax25_uid, &ax25_uid_list) {
hlist_del_init(&ax25_uid->uid_node);
ax25_uid_put(ax25_uid);
goto again;
}
write_unlock(&ax25_uid_lock);
}
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