* added netlink_proto_exit
* Tue Jan 22 18:32:44 BRST 2002 Arnaldo C. de Melo <acme@conectiva.com.br>
* use nlk_sk, as sk->protinfo is on a diet 8)
- *
+ * Fri Jul 22 19:51:12 MEST 2005 Harald Welte <laforge@gnumonks.org>
+ * - inc module use count of module that owns
+ * the kernel socket in case userspace opens
+ * socket of same protocol
+ * - remove all module support, since netlink is
+ * mandatory if CONFIG_NET=y these days
*/
#include <linux/config.h>
#include <linux/module.h>
+#include <linux/capability.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/major.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/bitops.h>
#include <linux/mm.h>
#include <linux/types.h>
+#include <linux/audit.h>
+#include <linux/selinux.h>
+#include <linux/vs_base.h>
+#include <linux/vs_context.h>
+#include <linux/vs_network.h>
+#include <linux/vs_limit.h>
+
#include <net/sock.h>
#include <net/scm.h>
+#include <net/netlink.h>
-#define Nprintk(a...)
-
-#if defined(CONFIG_NETLINK_DEV) || defined(CONFIG_NETLINK_DEV_MODULE)
-#define NL_EMULATE_DEV
-#endif
+#define NLGRPSZ(x) (ALIGN(x, sizeof(unsigned long) * 8) / 8)
-struct netlink_opt
-{
+struct netlink_sock {
+ /* struct sock has to be the first member of netlink_sock */
+ struct sock sk;
u32 pid;
- unsigned int groups;
u32 dst_pid;
- unsigned int dst_groups;
+ u32 dst_group;
+ u32 flags;
+ u32 subscriptions;
+ u32 ngroups;
+ unsigned long *groups;
unsigned long state;
- int (*handler)(int unit, struct sk_buff *skb);
wait_queue_head_t wait;
struct netlink_callback *cb;
spinlock_t cb_lock;
void (*data_ready)(struct sock *sk, int bytes);
+ struct module *module;
};
-#define nlk_sk(__sk) ((struct netlink_opt *)(__sk)->sk_protinfo)
+#define NETLINK_KERNEL_SOCKET 0x1
+#define NETLINK_RECV_PKTINFO 0x2
+
+static inline struct netlink_sock *nlk_sk(struct sock *sk)
+{
+ return (struct netlink_sock *)sk;
+}
struct nl_pid_hash {
struct hlist_head *table;
struct netlink_table {
struct nl_pid_hash hash;
struct hlist_head mc_list;
+ unsigned long *listeners;
+ unsigned int nl_nonroot;
+ unsigned int groups;
+ struct module *module;
+ int registered;
};
static struct netlink_table *nl_table;
static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait);
-static unsigned int nl_nonroot[MAX_LINKS];
-
-#ifdef NL_EMULATE_DEV
-static struct socket *netlink_kernel[MAX_LINKS];
-#endif
static int netlink_dump(struct sock *sk);
static void netlink_destroy_callback(struct netlink_callback *cb);
-static rwlock_t nl_table_lock = RW_LOCK_UNLOCKED;
+static DEFINE_RWLOCK(nl_table_lock);
static atomic_t nl_table_users = ATOMIC_INIT(0);
-static struct notifier_block *netlink_chain;
+static ATOMIC_NOTIFIER_HEAD(netlink_chain);
+
+static u32 netlink_group_mask(u32 group)
+{
+ return group ? 1 << (group - 1) : 0;
+}
static struct hlist_head *nl_pid_hashfn(struct nl_pid_hash *hash, u32 pid)
{
BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
BUG_TRAP(!nlk_sk(sk)->cb);
-
- kfree(nlk_sk(sk));
+ BUG_TRAP(!nlk_sk(sk)->groups);
}
/* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on SMP.
return 0;
}
-static struct proto_ops netlink_ops;
+static const struct proto_ops netlink_ops;
+
+static void
+netlink_update_listeners(struct sock *sk)
+{
+ struct netlink_table *tbl = &nl_table[sk->sk_protocol];
+ struct hlist_node *node;
+ unsigned long mask;
+ unsigned int i;
+
+ for (i = 0; i < NLGRPSZ(tbl->groups)/sizeof(unsigned long); i++) {
+ mask = 0;
+ sk_for_each_bound(sk, node, &tbl->mc_list)
+ mask |= nlk_sk(sk)->groups[i];
+ tbl->listeners[i] = mask;
+ }
+ /* this function is only called with the netlink table "grabbed", which
+ * makes sure updates are visible before bind or setsockopt return. */
+}
static int netlink_insert(struct sock *sk, u32 pid)
{
static void netlink_remove(struct sock *sk)
{
netlink_table_grab();
- nl_table[sk->sk_protocol].hash.entries--;
- sk_del_node_init(sk);
- if (nlk_sk(sk)->groups)
+ if (sk_del_node_init(sk))
+ nl_table[sk->sk_protocol].hash.entries--;
+ if (nlk_sk(sk)->subscriptions)
__sk_del_bind_node(sk);
netlink_table_ungrab();
}
-static int netlink_create(struct socket *sock, int protocol)
+static struct proto netlink_proto = {
+ .name = "NETLINK",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct netlink_sock),
+};
+
+static int __netlink_create(struct socket *sock, int protocol)
{
struct sock *sk;
- struct netlink_opt *nlk;
-
- sock->state = SS_UNCONNECTED;
-
- if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
- return -ESOCKTNOSUPPORT;
-
- if (protocol<0 || protocol >= MAX_LINKS)
- return -EPROTONOSUPPORT;
+ struct netlink_sock *nlk;
sock->ops = &netlink_ops;
- sk = sk_alloc(PF_NETLINK, GFP_KERNEL, 1, NULL);
+ sk = sk_alloc(PF_NETLINK, GFP_KERNEL, &netlink_proto, 1);
if (!sk)
return -ENOMEM;
- sock_init_data(sock,sk);
- sk_set_owner(sk, THIS_MODULE);
-
- nlk = sk->sk_protinfo = kmalloc(sizeof(*nlk), GFP_KERNEL);
- if (!nlk) {
- sk_free(sk);
- return -ENOMEM;
- }
- memset(nlk, 0, sizeof(*nlk));
+ sock_init_data(sock, sk);
+ nlk = nlk_sk(sk);
spin_lock_init(&nlk->cb_lock);
init_waitqueue_head(&nlk->wait);
- sk->sk_destruct = netlink_sock_destruct;
+ sk->sk_destruct = netlink_sock_destruct;
sk->sk_protocol = protocol;
return 0;
}
+static int netlink_create(struct socket *sock, int protocol)
+{
+ struct module *module = NULL;
+ struct netlink_sock *nlk;
+ unsigned int groups;
+ int err = 0;
+
+ sock->state = SS_UNCONNECTED;
+
+ if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
+ return -ESOCKTNOSUPPORT;
+
+ if (protocol<0 || protocol >= MAX_LINKS)
+ return -EPROTONOSUPPORT;
+
+ netlink_lock_table();
+#ifdef CONFIG_KMOD
+ if (!nl_table[protocol].registered) {
+ netlink_unlock_table();
+ request_module("net-pf-%d-proto-%d", PF_NETLINK, protocol);
+ netlink_lock_table();
+ }
+#endif
+ if (nl_table[protocol].registered &&
+ try_module_get(nl_table[protocol].module))
+ module = nl_table[protocol].module;
+ groups = nl_table[protocol].groups;
+ netlink_unlock_table();
+
+ if ((err = __netlink_create(sock, protocol)) < 0)
+ goto out_module;
+
+ nlk = nlk_sk(sock->sk);
+ nlk->module = module;
+out:
+ return err;
+
+out_module:
+ module_put(module);
+ goto out;
+}
+
static int netlink_release(struct socket *sock)
{
struct sock *sk = sock->sk;
- struct netlink_opt *nlk;
+ struct netlink_sock *nlk;
if (!sk)
return 0;
spin_lock(&nlk->cb_lock);
if (nlk->cb) {
- nlk->cb->done(nlk->cb);
+ if (nlk->cb->done)
+ nlk->cb->done(nlk->cb);
netlink_destroy_callback(nlk->cb);
nlk->cb = NULL;
- __sock_put(sk);
}
spin_unlock(&nlk->cb_lock);
skb_queue_purge(&sk->sk_write_queue);
- if (nlk->pid && !nlk->groups) {
+ if (nlk->pid && !nlk->subscriptions) {
struct netlink_notify n = {
.protocol = sk->sk_protocol,
.pid = nlk->pid,
};
- notifier_call_chain(&netlink_chain, NETLINK_URELEASE, &n);
+ atomic_notifier_call_chain(&netlink_chain,
+ NETLINK_URELEASE, &n);
}
-
+
+ if (nlk->module)
+ module_put(nlk->module);
+
+ netlink_table_grab();
+ if (nlk->flags & NETLINK_KERNEL_SOCKET) {
+ kfree(nl_table[sk->sk_protocol].listeners);
+ nl_table[sk->sk_protocol].module = NULL;
+ nl_table[sk->sk_protocol].registered = 0;
+ } else if (nlk->subscriptions)
+ netlink_update_listeners(sk);
+ netlink_table_ungrab();
+
+ kfree(nlk->groups);
+ nlk->groups = NULL;
+
sock_put(sk);
return 0;
}
struct hlist_head *head;
struct sock *osk;
struct hlist_node *node;
- s32 pid = current->pid;
+ s32 pid = current->tgid;
int err;
static s32 rover = -4097;
err = netlink_insert(sk, pid);
if (err == -EADDRINUSE)
goto retry;
- nlk_sk(sk)->groups = 0;
- return 0;
+
+ /* If 2 threads race to autobind, that is fine. */
+ if (err == -EBUSY)
+ err = 0;
+
+ return err;
}
static inline int netlink_capable(struct socket *sock, unsigned int flag)
{
- return (nl_nonroot[sock->sk->sk_protocol] & flag) ||
+ return (nl_table[sock->sk->sk_protocol].nl_nonroot & flag) ||
capable(CAP_NET_ADMIN);
}
+static void
+netlink_update_subscriptions(struct sock *sk, unsigned int subscriptions)
+{
+ struct netlink_sock *nlk = nlk_sk(sk);
+
+ if (nlk->subscriptions && !subscriptions)
+ __sk_del_bind_node(sk);
+ else if (!nlk->subscriptions && subscriptions)
+ sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list);
+ nlk->subscriptions = subscriptions;
+}
+
+static int netlink_alloc_groups(struct sock *sk)
+{
+ struct netlink_sock *nlk = nlk_sk(sk);
+ unsigned int groups;
+ int err = 0;
+
+ netlink_lock_table();
+ groups = nl_table[sk->sk_protocol].groups;
+ if (!nl_table[sk->sk_protocol].registered)
+ err = -ENOENT;
+ netlink_unlock_table();
+
+ if (err)
+ return err;
+
+ nlk->groups = kmalloc(NLGRPSZ(groups), GFP_KERNEL);
+ if (nlk->groups == NULL)
+ return -ENOMEM;
+ memset(nlk->groups, 0, NLGRPSZ(groups));
+ nlk->ngroups = groups;
+ return 0;
+}
+
static int netlink_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
{
struct sock *sk = sock->sk;
- struct netlink_opt *nlk = nlk_sk(sk);
+ struct netlink_sock *nlk = nlk_sk(sk);
struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
int err;
return -EINVAL;
/* Only superuser is allowed to listen multicasts */
- if (nladdr->nl_groups && !netlink_capable(sock, NL_NONROOT_RECV))
- return -EPERM;
+ if (nladdr->nl_groups) {
+ if (!netlink_capable(sock, NL_NONROOT_RECV))
+ return -EPERM;
+ if (nlk->groups == NULL) {
+ err = netlink_alloc_groups(sk);
+ if (err)
+ return err;
+ }
+ }
if (nlk->pid) {
if (nladdr->nl_pid != nlk->pid)
return err;
}
- if (!nladdr->nl_groups && !nlk->groups)
+ if (!nladdr->nl_groups && (nlk->groups == NULL || !(u32)nlk->groups[0]))
return 0;
netlink_table_grab();
- if (nlk->groups && !nladdr->nl_groups)
- __sk_del_bind_node(sk);
- else if (!nlk->groups && nladdr->nl_groups)
- sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list);
- nlk->groups = nladdr->nl_groups;
+ netlink_update_subscriptions(sk, nlk->subscriptions +
+ hweight32(nladdr->nl_groups) -
+ hweight32(nlk->groups[0]));
+ nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | nladdr->nl_groups;
+ netlink_update_listeners(sk);
netlink_table_ungrab();
return 0;
{
int err = 0;
struct sock *sk = sock->sk;
- struct netlink_opt *nlk = nlk_sk(sk);
+ struct netlink_sock *nlk = nlk_sk(sk);
struct sockaddr_nl *nladdr=(struct sockaddr_nl*)addr;
if (addr->sa_family == AF_UNSPEC) {
sk->sk_state = NETLINK_UNCONNECTED;
nlk->dst_pid = 0;
- nlk->dst_groups = 0;
+ nlk->dst_group = 0;
return 0;
}
if (addr->sa_family != AF_NETLINK)
if (err == 0) {
sk->sk_state = NETLINK_CONNECTED;
nlk->dst_pid = nladdr->nl_pid;
- nlk->dst_groups = nladdr->nl_groups;
+ nlk->dst_group = ffs(nladdr->nl_groups);
}
return err;
static int netlink_getname(struct socket *sock, struct sockaddr *addr, int *addr_len, int peer)
{
struct sock *sk = sock->sk;
- struct netlink_opt *nlk = nlk_sk(sk);
+ struct netlink_sock *nlk = nlk_sk(sk);
struct sockaddr_nl *nladdr=(struct sockaddr_nl *)addr;
nladdr->nl_family = AF_NETLINK;
if (peer) {
nladdr->nl_pid = nlk->dst_pid;
- nladdr->nl_groups = nlk->dst_groups;
+ nladdr->nl_groups = netlink_group_mask(nlk->dst_group);
} else {
nladdr->nl_pid = nlk->pid;
- nladdr->nl_groups = nlk->groups;
+ nladdr->nl_groups = nlk->groups ? nlk->groups[0] : 0;
}
return 0;
}
}
}
-struct sock *netlink_getsockbypid(struct sock *ssk, u32 pid)
+static struct sock *netlink_getsockbypid(struct sock *ssk, u32 pid)
{
int protocol = ssk->sk_protocol;
struct sock *sock;
- struct netlink_opt *nlk;
+ struct netlink_sock *nlk;
sock = netlink_lookup(protocol, pid);
if (!sock)
struct sock *netlink_getsockbyfilp(struct file *filp)
{
struct inode *inode = filp->f_dentry->d_inode;
- struct socket *socket;
struct sock *sock;
- if (!inode->i_sock || !(socket = SOCKET_I(inode)))
+ if (!S_ISSOCK(inode->i_mode))
return ERR_PTR(-ENOTSOCK);
- sock = socket->sk;
+ sock = SOCKET_I(inode)->sk;
if (sock->sk_family != AF_NETLINK)
return ERR_PTR(-EINVAL);
* 0: continue
* 1: repeat lookup - reference dropped while waiting for socket memory.
*/
-int netlink_attachskb(struct sock *sk, struct sk_buff *skb, int nonblock, long timeo)
+int netlink_attachskb(struct sock *sk, struct sk_buff *skb, int nonblock,
+ long timeo, struct sock *ssk)
{
- struct netlink_opt *nlk;
+ struct netlink_sock *nlk;
nlk = nlk_sk(sk);
-#ifdef NL_EMULATE_DEV
- if (nlk->handler)
- return 0;
-#endif
if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
test_bit(0, &nlk->state)) {
DECLARE_WAITQUEUE(wait, current);
if (!timeo) {
- if (!nlk->pid)
+ if (!ssk || nlk_sk(ssk)->pid == 0)
netlink_overrun(sk);
sock_put(sk);
kfree_skb(skb);
}
return 1;
}
- skb_orphan(skb);
skb_set_owner_r(skb, sk);
return 0;
}
int netlink_sendskb(struct sock *sk, struct sk_buff *skb, int protocol)
{
- struct netlink_opt *nlk;
int len = skb->len;
- nlk = nlk_sk(sk);
-#ifdef NL_EMULATE_DEV
- if (nlk->handler) {
- skb_orphan(skb);
- len = nlk->handler(protocol, skb);
- sock_put(sk);
- return len;
- }
-#endif
-
skb_queue_tail(&sk->sk_receive_queue, skb);
sk->sk_data_ready(sk, len);
sock_put(sk);
sock_put(sk);
}
-static inline void netlink_trim(struct sk_buff *skb, int allocation)
+static inline struct sk_buff *netlink_trim(struct sk_buff *skb,
+ gfp_t allocation)
{
- int delta = skb->end - skb->tail;
+ int delta;
- /* If the packet is charged to a socket, the modification
- * of truesize below is illegal and will corrupt socket
- * buffer accounting state.
- */
- BUG_ON(skb->list != NULL);
+ skb_orphan(skb);
+ delta = skb->end - skb->tail;
if (delta * 2 < skb->truesize)
- return;
- if (pskb_expand_head(skb, 0, -delta, allocation))
- return;
- skb->truesize -= delta;
+ return skb;
+
+ if (skb_shared(skb)) {
+ struct sk_buff *nskb = skb_clone(skb, allocation);
+ if (!nskb)
+ return skb;
+ kfree_skb(skb);
+ skb = nskb;
+ }
+
+ if (!pskb_expand_head(skb, 0, -delta, allocation))
+ skb->truesize -= delta;
+
+ return skb;
}
int netlink_unicast(struct sock *ssk, struct sk_buff *skb, u32 pid, int nonblock)
int err;
long timeo;
- netlink_trim(skb, gfp_any());
+ skb = netlink_trim(skb, gfp_any());
timeo = sock_sndtimeo(ssk, nonblock);
retry:
kfree_skb(skb);
return PTR_ERR(sk);
}
- err = netlink_attachskb(sk, skb, nonblock, timeo);
+ err = netlink_attachskb(sk, skb, nonblock, timeo, ssk);
if (err == 1)
goto retry;
if (err)
return netlink_sendskb(sk, skb, ssk->sk_protocol);
}
+int netlink_has_listeners(struct sock *sk, unsigned int group)
+{
+ int res = 0;
+
+ BUG_ON(!(nlk_sk(sk)->flags & NETLINK_KERNEL_SOCKET));
+ if (group - 1 < nl_table[sk->sk_protocol].groups)
+ res = test_bit(group - 1, nl_table[sk->sk_protocol].listeners);
+ return res;
+}
+EXPORT_SYMBOL_GPL(netlink_has_listeners);
+
static __inline__ int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb)
{
- struct netlink_opt *nlk = nlk_sk(sk);
-#ifdef NL_EMULATE_DEV
- if (nlk->handler) {
- skb_orphan(skb);
- nlk->handler(sk->sk_protocol, skb);
- return 0;
- } else
-#endif
+ struct netlink_sock *nlk = nlk_sk(sk);
+
if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf &&
!test_bit(0, &nlk->state)) {
- skb_orphan(skb);
skb_set_owner_r(skb, sk);
skb_queue_tail(&sk->sk_receive_queue, skb);
sk->sk_data_ready(sk, skb->len);
int failure;
int congested;
int delivered;
- int allocation;
+ gfp_t allocation;
struct sk_buff *skb, *skb2;
};
static inline int do_one_broadcast(struct sock *sk,
struct netlink_broadcast_data *p)
{
- struct netlink_opt *nlk = nlk_sk(sk);
+ struct netlink_sock *nlk = nlk_sk(sk);
int val;
if (p->exclude_sk == sk)
goto out;
- if (nlk->pid == p->pid || !(nlk->groups & p->group))
+ if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups ||
+ !test_bit(p->group - 1, nlk->groups))
goto out;
if (p->failure) {
sock_hold(sk);
if (p->skb2 == NULL) {
- if (atomic_read(&p->skb->users) != 1) {
+ if (skb_shared(p->skb)) {
p->skb2 = skb_clone(p->skb, p->allocation);
} else {
- p->skb2 = p->skb;
- atomic_inc(&p->skb->users);
+ p->skb2 = skb_get(p->skb);
+ /*
+ * skb ownership may have been set when
+ * delivered to a previous socket.
+ */
+ skb_orphan(p->skb2);
}
}
if (p->skb2 == NULL) {
}
int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 pid,
- u32 group, int allocation)
+ u32 group, gfp_t allocation)
{
struct netlink_broadcast_data info;
struct hlist_node *node;
struct sock *sk;
+ skb = netlink_trim(skb, allocation);
+
info.exclude_sk = ssk;
info.pid = pid;
info.group = group;
info.skb = skb;
info.skb2 = NULL;
- netlink_trim(skb, allocation);
-
- netlink_trim(skb, allocation);
-
/* While we sleep in clone, do not allow to change socket list */
netlink_lock_table();
sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
do_one_broadcast(sk, &info);
+ kfree_skb(skb);
+
netlink_unlock_table();
if (info.skb2)
kfree_skb(info.skb2);
- kfree_skb(skb);
if (info.delivered) {
if (info.congested && (allocation & __GFP_WAIT))
static inline int do_one_set_err(struct sock *sk,
struct netlink_set_err_data *p)
{
- struct netlink_opt *nlk = nlk_sk(sk);
+ struct netlink_sock *nlk = nlk_sk(sk);
if (sk == p->exclude_sk)
goto out;
- if (nlk->pid == p->pid || !(nlk->groups & p->group))
+ if (nlk->pid == p->pid || p->group - 1 >= nlk->ngroups ||
+ !test_bit(p->group - 1, nlk->groups))
goto out;
sk->sk_err = p->code;
read_unlock(&nl_table_lock);
}
+static int netlink_setsockopt(struct socket *sock, int level, int optname,
+ char __user *optval, int optlen)
+{
+ struct sock *sk = sock->sk;
+ struct netlink_sock *nlk = nlk_sk(sk);
+ int val = 0, err;
+
+ if (level != SOL_NETLINK)
+ return -ENOPROTOOPT;
+
+ if (optlen >= sizeof(int) &&
+ get_user(val, (int __user *)optval))
+ return -EFAULT;
+
+ switch (optname) {
+ case NETLINK_PKTINFO:
+ if (val)
+ nlk->flags |= NETLINK_RECV_PKTINFO;
+ else
+ nlk->flags &= ~NETLINK_RECV_PKTINFO;
+ err = 0;
+ break;
+ case NETLINK_ADD_MEMBERSHIP:
+ case NETLINK_DROP_MEMBERSHIP: {
+ unsigned int subscriptions;
+ int old, new = optname == NETLINK_ADD_MEMBERSHIP ? 1 : 0;
+
+ if (!netlink_capable(sock, NL_NONROOT_RECV))
+ return -EPERM;
+ if (nlk->groups == NULL) {
+ err = netlink_alloc_groups(sk);
+ if (err)
+ return err;
+ }
+ if (!val || val - 1 >= nlk->ngroups)
+ return -EINVAL;
+ netlink_table_grab();
+ old = test_bit(val - 1, nlk->groups);
+ subscriptions = nlk->subscriptions - old + new;
+ if (new)
+ __set_bit(val - 1, nlk->groups);
+ else
+ __clear_bit(val - 1, nlk->groups);
+ netlink_update_subscriptions(sk, subscriptions);
+ netlink_update_listeners(sk);
+ netlink_table_ungrab();
+ err = 0;
+ break;
+ }
+ default:
+ err = -ENOPROTOOPT;
+ }
+ return err;
+}
+
+static int netlink_getsockopt(struct socket *sock, int level, int optname,
+ char __user *optval, int __user *optlen)
+{
+ struct sock *sk = sock->sk;
+ struct netlink_sock *nlk = nlk_sk(sk);
+ int len, val, err;
+
+ if (level != SOL_NETLINK)
+ return -ENOPROTOOPT;
+
+ if (get_user(len, optlen))
+ return -EFAULT;
+ if (len < 0)
+ return -EINVAL;
+
+ switch (optname) {
+ case NETLINK_PKTINFO:
+ if (len < sizeof(int))
+ return -EINVAL;
+ len = sizeof(int);
+ val = nlk->flags & NETLINK_RECV_PKTINFO ? 1 : 0;
+ put_user(len, optlen);
+ put_user(val, optval);
+ err = 0;
+ break;
+ default:
+ err = -ENOPROTOOPT;
+ }
+ return err;
+}
+
+static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
+{
+ struct nl_pktinfo info;
+
+ info.group = NETLINK_CB(skb).dst_group;
+ put_cmsg(msg, SOL_NETLINK, NETLINK_PKTINFO, sizeof(info), &info);
+}
+
static inline void netlink_rcv_wake(struct sock *sk)
{
- struct netlink_opt *nlk = nlk_sk(sk);
+ struct netlink_sock *nlk = nlk_sk(sk);
- if (!skb_queue_len(&sk->sk_receive_queue))
+ if (skb_queue_empty(&sk->sk_receive_queue))
clear_bit(0, &nlk->state);
if (!test_bit(0, &nlk->state))
wake_up_interruptible(&nlk->wait);
{
struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
struct sock *sk = sock->sk;
- struct netlink_opt *nlk = nlk_sk(sk);
+ struct netlink_sock *nlk = nlk_sk(sk);
struct sockaddr_nl *addr=msg->msg_name;
u32 dst_pid;
- u32 dst_groups;
+ u32 dst_group;
struct sk_buff *skb;
int err;
struct scm_cookie scm;
if (addr->nl_family != AF_NETLINK)
return -EINVAL;
dst_pid = addr->nl_pid;
- dst_groups = addr->nl_groups;
- if (dst_groups && !netlink_capable(sock, NL_NONROOT_SEND))
+ dst_group = ffs(addr->nl_groups);
+ if (dst_group && !netlink_capable(sock, NL_NONROOT_SEND))
return -EPERM;
} else {
dst_pid = nlk->dst_pid;
- dst_groups = nlk->dst_groups;
+ dst_group = nlk->dst_group;
}
if (!nlk->pid) {
goto out;
NETLINK_CB(skb).pid = nlk->pid;
- NETLINK_CB(skb).groups = nlk->groups;
NETLINK_CB(skb).dst_pid = dst_pid;
- NETLINK_CB(skb).dst_groups = dst_groups;
+ NETLINK_CB(skb).dst_group = dst_group;
+ NETLINK_CB(skb).loginuid = audit_get_loginuid(current->audit_context);
+ selinux_get_task_sid(current, &(NETLINK_CB(skb).sid));
memcpy(NETLINK_CREDS(skb), &siocb->scm->creds, sizeof(struct ucred));
/* What can I do? Netlink is asynchronous, so that
goto out;
}
- if (dst_groups) {
+ if (dst_group) {
atomic_inc(&skb->users);
- netlink_broadcast(sk, skb, dst_pid, dst_groups, GFP_KERNEL);
+ netlink_broadcast(sk, skb, dst_pid, dst_group, GFP_KERNEL);
}
err = netlink_unicast(sk, skb, dst_pid, msg->msg_flags&MSG_DONTWAIT);
struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
struct scm_cookie scm;
struct sock *sk = sock->sk;
- struct netlink_opt *nlk = nlk_sk(sk);
+ struct netlink_sock *nlk = nlk_sk(sk);
int noblock = flags&MSG_DONTWAIT;
size_t copied;
struct sk_buff *skb;
addr->nl_family = AF_NETLINK;
addr->nl_pad = 0;
addr->nl_pid = NETLINK_CB(skb).pid;
- addr->nl_groups = NETLINK_CB(skb).dst_groups;
+ addr->nl_groups = netlink_group_mask(NETLINK_CB(skb).dst_group);
msg->msg_namelen = sizeof(*addr);
}
+ if (nlk->flags & NETLINK_RECV_PKTINFO)
+ netlink_cmsg_recv_pktinfo(msg, skb);
+
if (NULL == siocb->scm) {
memset(&scm, 0, sizeof(scm));
siocb->scm = &scm;
static void netlink_data_ready(struct sock *sk, int len)
{
- struct netlink_opt *nlk = nlk_sk(sk);
+ struct netlink_sock *nlk = nlk_sk(sk);
if (nlk->data_ready)
nlk->data_ready(sk, len);
*/
struct sock *
-netlink_kernel_create(int unit, void (*input)(struct sock *sk, int len))
+netlink_kernel_create(int unit, unsigned int groups,
+ void (*input)(struct sock *sk, int len),
+ struct module *module)
{
struct socket *sock;
struct sock *sk;
+ struct netlink_sock *nlk;
+ unsigned long *listeners = NULL;
if (!nl_table)
return NULL;
if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock))
return NULL;
- if (netlink_create(sock, unit) < 0) {
- sock_release(sock);
- return NULL;
- }
+ if (__netlink_create(sock, unit) < 0)
+ goto out_sock_release;
+
+ if (groups < 32)
+ groups = 32;
+
+ listeners = kzalloc(NLGRPSZ(groups), GFP_KERNEL);
+ if (!listeners)
+ goto out_sock_release;
+
sk = sock->sk;
sk->sk_data_ready = netlink_data_ready;
if (input)
nlk_sk(sk)->data_ready = input;
- if (netlink_insert(sk, 0)) {
- sock_release(sock);
- return NULL;
- }
+ if (netlink_insert(sk, 0))
+ goto out_sock_release;
+
+ nlk = nlk_sk(sk);
+ nlk->flags |= NETLINK_KERNEL_SOCKET;
+
+ netlink_table_grab();
+ nl_table[unit].groups = groups;
+ nl_table[unit].listeners = listeners;
+ nl_table[unit].module = module;
+ nl_table[unit].registered = 1;
+ netlink_table_ungrab();
+
return sk;
+
+out_sock_release:
+ kfree(listeners);
+ sock_release(sock);
+ return NULL;
}
void netlink_set_nonroot(int protocol, unsigned int flags)
{
if ((unsigned int)protocol < MAX_LINKS)
- nl_nonroot[protocol] = flags;
+ nl_table[protocol].nl_nonroot = flags;
}
static void netlink_destroy_callback(struct netlink_callback *cb)
static int netlink_dump(struct sock *sk)
{
- struct netlink_opt *nlk = nlk_sk(sk);
+ struct netlink_sock *nlk = nlk_sk(sk);
struct netlink_callback *cb;
struct sk_buff *skb;
struct nlmsghdr *nlh;
return 0;
}
- nlh = __nlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq, NLMSG_DONE, sizeof(int));
- nlh->nlmsg_flags |= NLM_F_MULTI;
+ nlh = NLMSG_NEW_ANSWER(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI);
memcpy(NLMSG_DATA(nlh), &len, sizeof(len));
skb_queue_tail(&sk->sk_receive_queue, skb);
sk->sk_data_ready(sk, skb->len);
- cb->done(cb);
+ if (cb->done)
+ cb->done(cb);
nlk->cb = NULL;
spin_unlock(&nlk->cb_lock);
netlink_destroy_callback(cb);
- sock_put(sk);
return 0;
+
+nlmsg_failure:
+ return -ENOBUFS;
}
int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
{
struct netlink_callback *cb;
struct sock *sk;
- struct netlink_opt *nlk;
+ struct netlink_sock *nlk;
cb = kmalloc(sizeof(*cb), GFP_KERNEL);
if (cb == NULL)
spin_unlock(&nlk->cb_lock);
netlink_dump(sk);
+ sock_put(sk);
return 0;
}
}
rep = __nlmsg_put(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
- NLMSG_ERROR, sizeof(struct nlmsgerr));
+ NLMSG_ERROR, sizeof(struct nlmsgerr), 0);
errmsg = NLMSG_DATA(rep);
errmsg->error = err;
memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(struct nlmsghdr));
netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT);
}
+static int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *,
+ struct nlmsghdr *, int *))
+{
+ unsigned int total_len;
+ struct nlmsghdr *nlh;
+ int err;
-#ifdef NL_EMULATE_DEV
+ while (skb->len >= nlmsg_total_size(0)) {
+ nlh = (struct nlmsghdr *) skb->data;
-static rwlock_t nl_emu_lock = RW_LOCK_UNLOCKED;
+ if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len)
+ return 0;
+
+ total_len = min(NLMSG_ALIGN(nlh->nlmsg_len), skb->len);
+
+ if (cb(skb, nlh, &err) < 0) {
+ /* Not an error, but we have to interrupt processing
+ * here. Note: that in this case we do not pull
+ * message from skb, it will be processed later.
+ */
+ if (err == 0)
+ return -1;
+ netlink_ack(skb, nlh, err);
+ } else if (nlh->nlmsg_flags & NLM_F_ACK)
+ netlink_ack(skb, nlh, 0);
+
+ skb_pull(skb, total_len);
+ }
-/*
- * Backward compatibility.
- */
-
-int netlink_attach(int unit, int (*function)(int, struct sk_buff *skb))
-{
- struct sock *sk = netlink_kernel_create(unit, NULL);
- if (sk == NULL)
- return -ENOBUFS;
- nlk_sk(sk)->handler = function;
- write_lock_bh(&nl_emu_lock);
- netlink_kernel[unit] = sk->sk_socket;
- write_unlock_bh(&nl_emu_lock);
return 0;
}
-void netlink_detach(int unit)
+/**
+ * nelink_run_queue - Process netlink receive queue.
+ * @sk: Netlink socket containing the queue
+ * @qlen: Place to store queue length upon entry
+ * @cb: Callback function invoked for each netlink message found
+ *
+ * Processes as much as there was in the queue upon entry and invokes
+ * a callback function for each netlink message found. The callback
+ * function may refuse a message by returning a negative error code
+ * but setting the error pointer to 0 in which case this function
+ * returns with a qlen != 0.
+ *
+ * qlen must be initialized to 0 before the initial entry, afterwards
+ * the function may be called repeatedly until qlen reaches 0.
+ */
+void netlink_run_queue(struct sock *sk, unsigned int *qlen,
+ int (*cb)(struct sk_buff *, struct nlmsghdr *, int *))
{
- struct socket *sock;
+ struct sk_buff *skb;
- write_lock_bh(&nl_emu_lock);
- sock = netlink_kernel[unit];
- netlink_kernel[unit] = NULL;
- write_unlock_bh(&nl_emu_lock);
+ if (!*qlen || *qlen > skb_queue_len(&sk->sk_receive_queue))
+ *qlen = skb_queue_len(&sk->sk_receive_queue);
+
+ for (; *qlen; (*qlen)--) {
+ skb = skb_dequeue(&sk->sk_receive_queue);
+ if (netlink_rcv_skb(skb, cb)) {
+ if (skb->len)
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ else {
+ kfree_skb(skb);
+ (*qlen)--;
+ }
+ break;
+ }
- sock_release(sock);
+ kfree_skb(skb);
+ }
}
-int netlink_post(int unit, struct sk_buff *skb)
+/**
+ * netlink_queue_skip - Skip netlink message while processing queue.
+ * @nlh: Netlink message to be skipped
+ * @skb: Socket buffer containing the netlink messages.
+ *
+ * Pulls the given netlink message off the socket buffer so the next
+ * call to netlink_queue_run() will not reconsider the message.
+ */
+void netlink_queue_skip(struct nlmsghdr *nlh, struct sk_buff *skb)
{
- struct socket *sock;
-
- read_lock(&nl_emu_lock);
- sock = netlink_kernel[unit];
- if (sock) {
- struct sock *sk = sock->sk;
- memset(skb->cb, 0, sizeof(skb->cb));
- sock_hold(sk);
- read_unlock(&nl_emu_lock);
+ int msglen = NLMSG_ALIGN(nlh->nlmsg_len);
- netlink_broadcast(sk, skb, 0, ~0, GFP_ATOMIC);
+ if (msglen > skb->len)
+ msglen = skb->len;
- sock_put(sk);
- return 0;
- }
- read_unlock(&nl_emu_lock);
- return -EUNATCH;
+ skb_pull(skb, msglen);
}
-#endif
-
#ifdef CONFIG_PROC_FS
struct nl_seq_iter {
int link;
"Rmem Wmem Dump Locks\n");
else {
struct sock *s = v;
- struct netlink_opt *nlk = nlk_sk(s);
+ struct netlink_sock *nlk = nlk_sk(s);
seq_printf(seq, "%p %-3d %-6d %08x %-8d %-8d %p %d\n",
s,
s->sk_protocol,
nlk->pid,
- nlk->groups,
+ nlk->groups ? (u32)nlk->groups[0] : 0,
atomic_read(&s->sk_rmem_alloc),
atomic_read(&s->sk_wmem_alloc),
nlk->cb,
int netlink_register_notifier(struct notifier_block *nb)
{
- return notifier_chain_register(&netlink_chain, nb);
+ return atomic_notifier_chain_register(&netlink_chain, nb);
}
int netlink_unregister_notifier(struct notifier_block *nb)
{
- return notifier_chain_unregister(&netlink_chain, nb);
+ return atomic_notifier_chain_unregister(&netlink_chain, nb);
}
-static struct proto_ops netlink_ops = {
+static const struct proto_ops netlink_ops = {
.family = PF_NETLINK,
.owner = THIS_MODULE,
.release = netlink_release,
.ioctl = sock_no_ioctl,
.listen = sock_no_listen,
.shutdown = sock_no_shutdown,
- .setsockopt = sock_no_setsockopt,
- .getsockopt = sock_no_getsockopt,
+ .setsockopt = netlink_setsockopt,
+ .getsockopt = netlink_getsockopt,
.sendmsg = netlink_sendmsg,
.recvmsg = netlink_recvmsg,
.mmap = sock_no_mmap,
int i;
unsigned long max;
unsigned int order;
+ int err = proto_register(&netlink_proto, 0);
+
+ if (err != 0)
+ goto out;
if (sizeof(struct netlink_skb_parms) > sizeof(dummy_skb->cb))
netlink_skb_parms_too_large();
#endif
/* The netlink device handler may be needed early. */
rtnetlink_init();
- return 0;
-}
-
-static void __exit netlink_proto_exit(void)
-{
- sock_unregister(PF_NETLINK);
- proc_net_remove("netlink");
- kfree(nl_table);
- nl_table = NULL;
+out:
+ return err;
}
core_initcall(netlink_proto_init);
-module_exit(netlink_proto_exit);
-
-MODULE_LICENSE("GPL");
-
-MODULE_ALIAS_NETPROTO(PF_NETLINK);
EXPORT_SYMBOL(netlink_ack);
+EXPORT_SYMBOL(netlink_run_queue);
+EXPORT_SYMBOL(netlink_queue_skip);
EXPORT_SYMBOL(netlink_broadcast);
EXPORT_SYMBOL(netlink_dump_start);
EXPORT_SYMBOL(netlink_kernel_create);
EXPORT_SYMBOL(netlink_unicast);
EXPORT_SYMBOL(netlink_unregister_notifier);
-#if defined(CONFIG_NETLINK_DEV) || defined(CONFIG_NETLINK_DEV_MODULE)
-EXPORT_SYMBOL(netlink_attach);
-EXPORT_SYMBOL(netlink_detach);
-EXPORT_SYMBOL(netlink_post);
-#endif