cregit-Linux how code gets into the kernel

Release 4.11 net/decnet/dn_dev.c

Directory: net/decnet
/*
 * DECnet       An implementation of the DECnet protocol suite for the LINUX
 *              operating system.  DECnet is implemented using the  BSD Socket
 *              interface as the means of communication with the user level.
 *
 *              DECnet Device Layer
 *
 * Authors:     Steve Whitehouse <SteveW@ACM.org>
 *              Eduardo Marcelo Serrat <emserrat@geocities.com>
 *
 * Changes:
 *          Steve Whitehouse : Devices now see incoming frames so they
 *                             can mark on who it came from.
 *          Steve Whitehouse : Fixed bug in creating neighbours. Each neighbour
 *                             can now have a device specific setup func.
 *          Steve Whitehouse : Added /proc/sys/net/decnet/conf/<dev>/
 *          Steve Whitehouse : Fixed bug which sometimes killed timer
 *          Steve Whitehouse : Multiple ifaddr support
 *          Steve Whitehouse : SIOCGIFCONF is now a compile time option
 *          Steve Whitehouse : /proc/sys/net/decnet/conf/<sys>/forwarding
 *          Steve Whitehouse : Removed timer1 - it's a user space issue now
 *         Patrick Caulfield : Fixed router hello message format
 *          Steve Whitehouse : Got rid of constant sizes for blksize for
 *                             devices. All mtu based now.
 */

#include <linux/capability.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/if_addr.h>
#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/skbuff.h>
#include <linux/sysctl.h>
#include <linux/notifier.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/uaccess.h>
#include <net/net_namespace.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/fib_rules.h>
#include <net/netlink.h>
#include <net/dn.h>
#include <net/dn_dev.h>
#include <net/dn_route.h>
#include <net/dn_neigh.h>
#include <net/dn_fib.h>


#define DN_IFREQ_SIZE (sizeof(struct ifreq) - sizeof(struct sockaddr) + sizeof(struct sockaddr_dn))


static char dn_rt_all_end_mcast[ETH_ALEN] = {0xAB,0x00,0x00,0x04,0x00,0x00};

static char dn_rt_all_rt_mcast[ETH_ALEN]  = {0xAB,0x00,0x00,0x03,0x00,0x00};

static char dn_hiord[ETH_ALEN]            = {0xAA,0x00,0x04,0x00,0x00,0x00};

static unsigned char dn_eco_version[3]    = {0x02,0x00,0x00};

extern struct neigh_table dn_neigh_table;

/*
 * decnet_address is kept in network order.
 */

__le16 decnet_address = 0;

static DEFINE_SPINLOCK(dndev_lock);

static struct net_device *decnet_default_device;
static BLOCKING_NOTIFIER_HEAD(dnaddr_chain);

static struct dn_dev *dn_dev_create(struct net_device *dev, int *err);
static void dn_dev_delete(struct net_device *dev);
static void dn_ifaddr_notify(int event, struct dn_ifaddr *ifa);

static int dn_eth_up(struct net_device *);
static void dn_eth_down(struct net_device *);
static void dn_send_brd_hello(struct net_device *dev, struct dn_ifaddr *ifa);
static void dn_send_ptp_hello(struct net_device *dev, struct dn_ifaddr *ifa);


static struct dn_dev_parms dn_dev_list[] =  {
{
	.type =		ARPHRD_ETHER, /* Ethernet */
	.mode =		DN_DEV_BCAST,
	.state =	DN_DEV_S_RU,
	.t2 =		1,
	.t3 =		10,
	.name =		"ethernet",
	.up =		dn_eth_up,
	.down = 	dn_eth_down,
	.timer3 =	dn_send_brd_hello,
},
{
	.type =		ARPHRD_IPGRE, /* DECnet tunneled over GRE in IP */
	.mode =		DN_DEV_BCAST,
	.state =	DN_DEV_S_RU,
	.t2 =		1,
	.t3 =		10,
	.name =		"ipgre",
	.timer3 =	dn_send_brd_hello,
},
#if 0
{
        .type =         ARPHRD_X25, /* Bog standard X.25 */
	.mode =         DN_DEV_UCAST,
        .state =        DN_DEV_S_DS,
        .t2 =           1,
        .t3 =           120,
        .name =         "x25",
        .timer3 =       dn_send_ptp_hello,
},
#endif
#if 0
{
        .type =         ARPHRD_PPP, /* DECnet over PPP */
	.mode =         DN_DEV_BCAST,
        .state =        DN_DEV_S_RU,
        .t2 =           1,
        .t3 =           10,
        .name =         "ppp",
        .timer3 =       dn_send_brd_hello,
},
#endif
{
	.type =		ARPHRD_DDCMP, /* DECnet over DDCMP */
	.mode =		DN_DEV_UCAST,
	.state =	DN_DEV_S_DS,
	.t2 =		1,
	.t3 =		120,
	.name =		"ddcmp",
	.timer3 =	dn_send_ptp_hello,
},
{
	.type =		ARPHRD_LOOPBACK, /* Loopback interface - always last */
	.mode =		DN_DEV_BCAST,
	.state =	DN_DEV_S_RU,
	.t2 =		1,
	.t3 =		10,
	.name =		"loopback",
	.timer3 =	dn_send_brd_hello,
}
};


#define DN_DEV_LIST_SIZE ARRAY_SIZE(dn_dev_list)


#define DN_DEV_PARMS_OFFSET(x) offsetof(struct dn_dev_parms, x)

#ifdef CONFIG_SYSCTL


static int min_t2[] = { 1 };

static int max_t2[] = { 60 }; 
/* No max specified, but this seems sensible */

static int min_t3[] = { 1 };

static int max_t3[] = { 8191 }; 
/* Must fit in 16 bits when multiplied by BCT3MULT or T3MULT */


static int min_priority[1];

static int max_priority[] = { 127 }; 
/* From DECnet spec */

static int dn_forwarding_proc(struct ctl_table *, int,
			void __user *, size_t *, loff_t *);

static struct dn_dev_sysctl_table {
	
struct ctl_table_header *sysctl_header;
	
struct ctl_table dn_dev_vars[5];
} 
dn_dev_sysctl = {
	NULL,
	{
	{
		.procname = "forwarding",
		.data = (void *)DN_DEV_PARMS_OFFSET(forwarding),
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = dn_forwarding_proc,
        },
	{
		.procname = "priority",
		.data = (void *)DN_DEV_PARMS_OFFSET(priority),
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = proc_dointvec_minmax,
		.extra1 = &min_priority,
		.extra2 = &max_priority
	},
	{
		.procname = "t2",
		.data = (void *)DN_DEV_PARMS_OFFSET(t2),
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = proc_dointvec_minmax,
		.extra1 = &min_t2,
		.extra2 = &max_t2
	},
	{
		.procname = "t3",
		.data = (void *)DN_DEV_PARMS_OFFSET(t3),
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = proc_dointvec_minmax,
		.extra1 = &min_t3,
		.extra2 = &max_t3
	},
	{ }
	},
};




static void dn_dev_sysctl_register(struct net_device *dev, struct dn_dev_parms *parms)
{
	struct dn_dev_sysctl_table *t;
	int i;

	char path[sizeof("net/decnet/conf/") + IFNAMSIZ];

	t = kmemdup(&dn_dev_sysctl, sizeof(*t), GFP_KERNEL);
	if (t == NULL)
		return;

	for(i = 0; i < ARRAY_SIZE(t->dn_dev_vars) - 1; i++) {
		long offset = (long)t->dn_dev_vars[i].data;
		t->dn_dev_vars[i].data = ((char *)parms) + offset;
	}

	snprintf(path, sizeof(path), "net/decnet/conf/%s",
		dev? dev->name : parms->name);

	t->dn_dev_vars[0].extra1 = (void *)dev;

	t->sysctl_header = register_net_sysctl(&init_net, path, t->dn_dev_vars);
	if (t->sysctl_header == NULL)
		kfree(t);
	else
		parms->sysctl = t;
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)12968.98%337.50%


Eric W. Biedermann2915.51%225.00%


Pavel Emelyanov2412.83%112.50%


Arnaldo Carvalho de Melo42.14%112.50%


Andries E. Brouwer10.53%112.50%


Total187100.00%8100.00%






static void dn_dev_sysctl_unregister(struct dn_dev_parms *parms)
{
	if (parms->sysctl) {
		struct dn_dev_sysctl_table *t = parms->sysctl;
		parms->sysctl = NULL;
		unregister_net_sysctl_table(t->sysctl_header);
		kfree(t);
	}
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)4597.83%150.00%


Eric W. Biedermann12.17%150.00%


Total46100.00%2100.00%






static int dn_forwarding_proc(struct ctl_table *table, int write,
				void __user *buffer,
				size_t *lenp, loff_t *ppos)
{
#ifdef CONFIG_DECNET_ROUTER
	struct net_device *dev = table->extra1;
	struct dn_dev *dn_db;
	int err;
	int tmp, old;

	if (table->extra1 == NULL)
		return -EINVAL;

	dn_db = rcu_dereference_raw(dev->dn_ptr);
	old = dn_db->parms.forwarding;

	err = proc_dointvec(table, write, buffer, lenp, ppos);

	if ((err >= 0) && write) {
		if (dn_db->parms.forwarding < 0)
			dn_db->parms.forwarding = 0;
		if (dn_db->parms.forwarding > 2)
			dn_db->parms.forwarding = 2;
		/*
                 * What an ugly hack this is... its works, just. It
                 * would be nice if sysctl/proc were just that little
                 * bit more flexible so I don't have to write a special
                 * routine, or suffer hacks like this - SJW
                 */
		tmp = dn_db->parms.forwarding;
		dn_db->parms.forwarding = old;
		if (dn_db->parms.down)
			dn_db->parms.down(dev);
		dn_db->parms.forwarding = tmp;
		if (dn_db->parms.up)
			dn_db->parms.up(dev);
	}

	return err;
#else
	return -EINVAL;
#endif
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)20394.86%233.33%


Linus Torvalds62.80%116.67%


Eric Dumazet31.40%116.67%


Al Viro10.47%116.67%


Joe Perches10.47%116.67%


Total214100.00%6100.00%



#else /* CONFIG_SYSCTL */



static void dn_dev_sysctl_unregister(struct dn_dev_parms *parms)
{
}

Contributors
PersonTokensPropCommitsCommitProp
Hideaki Yoshifuji / 吉藤英明10100.00%1100.00%


Total10100.00%1100.00%






static void dn_dev_sysctl_register(struct net_device *dev, struct dn_dev_parms *parms)
{
}


Contributors
PersonTokensPropCommitsCommitProp
Hideaki Yoshifuji / 吉藤英明15100.00%1100.00%


Total15100.00%1100.00%



#endif /* CONFIG_SYSCTL */




static inline __u16 mtu2blksize(struct net_device *dev)
{
	u32 blksize = dev->mtu;
	if (blksize > 0xffff)
		blksize = 0xffff;

	if (dev->type == ARPHRD_ETHER ||
	    dev->type == ARPHRD_PPP ||
	    dev->type == ARPHRD_IPGRE ||
	    dev->type == ARPHRD_LOOPBACK)
		blksize -= 2;

	return (__u16)blksize;
}


Contributors
PersonTokensPropCommitsCommitProp
Hideaki Yoshifuji / 吉藤英明6396.92%150.00%


Linus Torvalds (pre-git)23.08%150.00%


Total65100.00%2100.00%






static struct dn_ifaddr *dn_dev_alloc_ifa(void)
{
	struct dn_ifaddr *ifa;

	ifa = kzalloc(sizeof(*ifa), GFP_KERNEL);

	return ifa;
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)3096.77%150.00%


Panagiotis Issaris13.23%150.00%


Total31100.00%2100.00%






static void dn_dev_free_ifa(struct dn_ifaddr *ifa)
{
	kfree_rcu(ifa, rcu);
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)1583.33%133.33%


Lai Jiangshan211.11%133.33%


Eric Dumazet15.56%133.33%


Total18100.00%3100.00%






static void dn_dev_del_ifa(struct dn_dev *dn_db, struct dn_ifaddr __rcu **ifap, int destroy)
{
	struct dn_ifaddr *ifa1 = rtnl_dereference(*ifap);
	unsigned char mac_addr[6];
	struct net_device *dev = dn_db->dev;

	ASSERT_RTNL();

	*ifap = ifa1->ifa_next;

	if (dn_db->dev->type == ARPHRD_ETHER) {
		if (ifa1->ifa_local != dn_eth2dn(dev->dev_addr)) {
			dn_dn2eth(mac_addr, ifa1->ifa_local);
			dev_mc_del(dev, mac_addr);
		}
	}

	dn_ifaddr_notify(RTM_DELADDR, ifa1);
	blocking_notifier_call_chain(&dnaddr_chain, NETDEV_DOWN, ifa1);
	if (destroy) {
		dn_dev_free_ifa(ifa1);

		if (dn_db->ifa_list == NULL)
			dn_dev_delete(dn_db->dev);
	}
}


Contributors
PersonTokensPropCommitsCommitProp
Steven Whitehouse8357.64%228.57%


Linus Torvalds (pre-git)5437.50%114.29%


Eric Dumazet42.78%114.29%


Jiri Pirko10.69%114.29%


Alan Stern10.69%114.29%


Thomas Graf10.69%114.29%


Total144100.00%7100.00%






static int dn_dev_insert_ifa(struct dn_dev *dn_db, struct dn_ifaddr *ifa)
{
	struct net_device *dev = dn_db->dev;
	struct dn_ifaddr *ifa1;
	unsigned char mac_addr[6];

	ASSERT_RTNL();

	/* Check for duplicates */
	for (ifa1 = rtnl_dereference(dn_db->ifa_list);
	     ifa1 != NULL;
	     ifa1 = rtnl_dereference(ifa1->ifa_next)) {
		if (ifa1->ifa_local == ifa->ifa_local)
			return -EEXIST;
	}

	if (dev->type == ARPHRD_ETHER) {
		if (ifa->ifa_local != dn_eth2dn(dev->dev_addr)) {
			dn_dn2eth(mac_addr, ifa->ifa_local);
			dev_mc_add(dev, mac_addr);
		}
	}

	ifa->ifa_next = dn_db->ifa_list;
	rcu_assign_pointer(dn_db->ifa_list, ifa);

	dn_ifaddr_notify(RTM_NEWADDR, ifa);
	blocking_notifier_call_chain(&dnaddr_chain, NETDEV_UP, ifa);

	return 0;
}


Contributors
PersonTokensPropCommitsCommitProp
Steven Whitehouse10767.30%228.57%


Linus Torvalds (pre-git)3823.90%114.29%


Eric Dumazet127.55%228.57%


Thomas Graf10.63%114.29%


Alan Stern10.63%114.29%


Total159100.00%7100.00%






static int dn_dev_set_ifa(struct net_device *dev, struct dn_ifaddr *ifa)
{
	struct dn_dev *dn_db = rtnl_dereference(dev->dn_ptr);
	int rv;

	if (dn_db == NULL) {
		int err;
		dn_db = dn_dev_create(dev, &err);
		if (dn_db == NULL)
			return err;
	}

	ifa->ifa_dev = dn_db;

	if (dev->flags & IFF_LOOPBACK)
		ifa->ifa_scope = RT_SCOPE_HOST;

	rv = dn_dev_insert_ifa(dn_db, ifa);
	if (rv)
		dn_dev_free_ifa(ifa);
	return rv;
}



Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)8280.39%250.00%


Steven Whitehouse1716.67%125.00%


Eric Dumazet32.94%125.00%


Total102100.00%4100.00%






int dn_dev_ioctl(unsigned int cmd, void __user *arg)
{
	char buffer[DN_IFREQ_SIZE];
	struct ifreq *ifr = (struct ifreq *)buffer;
	struct sockaddr_dn *sdn = (struct sockaddr_dn *)&ifr->ifr_addr;
	struct dn_dev *dn_db;
	struct net_device *dev;
	struct dn_ifaddr *ifa = NULL;
	struct dn_ifaddr __rcu **ifap = NULL;
	int ret = 0;

	if (copy_from_user(ifr, arg, DN_IFREQ_SIZE))
		return -EFAULT;
	ifr->ifr_name[IFNAMSIZ-1] = 0;

	dev_load(&init_net, ifr->ifr_name);

	switch (cmd) {
	case SIOCGIFADDR:
		break;
	case SIOCSIFADDR:
		if (!capable(CAP_NET_ADMIN))
			return -EACCES;
		if (sdn->sdn_family != AF_DECnet)
			return -EINVAL;
		break;
	default:
		return -EINVAL;
	}

	rtnl_lock();

	if ((dev = __dev_get_by_name(&init_net, ifr->ifr_name)) == NULL) {
		ret = -ENODEV;
		goto done;
	}

	if ((dn_db = rtnl_dereference(dev->dn_ptr)) != NULL) {
		for (ifap = &dn_db->ifa_list;
		     (ifa = rtnl_dereference(*ifap)) != NULL;
		     ifap = &ifa->ifa_next)
			if (strcmp(ifr->ifr_name, ifa->ifa_label) == 0)
				break;
	}

	if (ifa == NULL && cmd != SIOCSIFADDR) {
		ret = -EADDRNOTAVAIL;
		goto done;
	}

	switch (cmd) {
	case SIOCGIFADDR:
		*((__le16 *)sdn->sdn_nodeaddr) = ifa->ifa_local;
		goto rarok;

	case SIOCSIFADDR:
		if (!ifa) {
			if ((ifa = dn_dev_alloc_ifa()) == NULL) {
				ret = -ENOBUFS;
				break;
			}
			memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
		} else {
			if (ifa->ifa_local == dn_saddr2dn(sdn))
				break;
			dn_dev_del_ifa(dn_db, ifap, 0);
		}

		ifa->ifa_local = ifa->ifa_address = dn_saddr2dn(sdn);

		ret = dn_dev_set_ifa(dev, ifa);
	}
done:
	rtnl_unlock();

	return ret;
rarok:
	if (copy_to_user(arg, ifr, DN_IFREQ_SIZE))
		ret = -EFAULT;
	goto done;
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)38292.49%436.36%


Steven Whitehouse133.15%327.27%


Eric Dumazet102.42%19.09%


Eric W. Biedermann61.45%19.09%


Al Viro10.24%19.09%


David S. Miller10.24%19.09%


Total413100.00%11100.00%






struct net_device *dn_dev_get_default(void)
{
	struct net_device *dev;

	spin_lock(&dndev_lock);
	dev = decnet_default_device;
	if (dev) {
		if (dev->dn_ptr)
			dev_hold(dev);
		else
			dev = NULL;
	}
	spin_unlock(&dndev_lock);

	return dev;
}


Contributors
PersonTokensPropCommitsCommitProp
Hideaki Yoshifuji / 吉藤英明5396.36%150.00%


Stephen Hemminger23.64%150.00%


Total55100.00%2100.00%






int dn_dev_set_default(struct net_device *dev, int force)
{
	struct net_device *old = NULL;
	int rv = -EBUSY;
	if (!dev->dn_ptr)
		return -ENODEV;

	spin_lock(&dndev_lock);
	if (force || decnet_default_device == NULL) {
		old = decnet_default_device;
		decnet_default_device = dev;
		rv = 0;
	}
	spin_unlock(&dndev_lock);

	if (old)
		dev_put(old);
	return rv;
}


Contributors
PersonTokensPropCommitsCommitProp
Hideaki Yoshifuji / 吉藤英明8096.39%133.33%


Stephen Hemminger22.41%133.33%


Patrick Caulfield11.20%133.33%


Total83100.00%3100.00%






static void dn_dev_check_default(struct net_device *dev)
{
	spin_lock(&dndev_lock);
	if (dev == decnet_default_device) {
		decnet_default_device = NULL;
	} else {
		dev = NULL;
	}
	spin_unlock(&dndev_lock);

	if (dev)
		dev_put(dev);
}


Contributors
PersonTokensPropCommitsCommitProp
Hideaki Yoshifuji / 吉藤英明4996.08%150.00%


Stephen Hemminger23.92%150.00%


Total51100.00%2100.00%



/*
 * Called with RTNL
 */



static struct dn_dev *dn_dev_by_index(int ifindex)
{
	struct net_device *dev;
	struct dn_dev *dn_dev = NULL;

	dev = __dev_get_by_index(&init_net, ifindex);
	if (dev)
		dn_dev = rtnl_dereference(dev->dn_ptr);

	return dn_dev;
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)4285.71%240.00%


Eric Dumazet48.16%240.00%


Eric W. Biedermann36.12%120.00%


Total49100.00%5100.00%




static const struct nla_policy dn_ifa_policy[IFA_MAX+1] = {
	[IFA_ADDRESS]		= { .type = NLA_U16 },
	[IFA_LOCAL]		= { .type = NLA_U16 },
	[IFA_LABEL]		= { .type = NLA_STRING,
				    .len = IFNAMSIZ - 1 },
	[IFA_FLAGS]		= { .type = NLA_U32 },
};




static int dn_nl_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh)
{
	struct net *net = sock_net(skb->sk);
	struct nlattr *tb[IFA_MAX+1];
	struct dn_dev *dn_db;
	struct ifaddrmsg *ifm;
	struct dn_ifaddr *ifa;
	struct dn_ifaddr __rcu **ifap;
	int err = -EINVAL;

	if (!netlink_capable(skb, CAP_NET_ADMIN))
		return -EPERM;

	if (!net_eq(net, &init_net))
		goto errout;

	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, dn_ifa_policy);
	if (err < 0)
		goto errout;

	err = -ENODEV;
	ifm = nlmsg_data(nlh);
	if ((dn_db = dn_dev_by_index(ifm->ifa_index)) == NULL)
		goto errout;

	err = -EADDRNOTAVAIL;
	for (ifap = &dn_db->ifa_list;
	     (ifa = rtnl_dereference(*ifap)) != NULL;
	     ifap = &ifa->ifa_next) {
		if (tb[IFA_LOCAL] &&
		    nla_memcmp(tb[IFA_LOCAL], &ifa->ifa_local, 2))
			continue;

		if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
			continue;

		dn_dev_del_ifa(dn_db, ifap, 1);
		return 0;
	}

errout:
	return err;
}


Contributors
PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)11847.77%111.11%


Thomas Graf6727.13%111.11%


Denis V. Lunev218.50%111.11%


Eric W. Biedermann145.67%222.22%


Pavel Emelyanov104.05%111.11%


Eric Dumazet93.64%111.11%


Octavian Purdila52.02%111.11%


Hideaki Yoshifuji / 吉藤英明31.21%111.11%


Total247100.00%9100.00%






static int dn_nl_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh)
{
	struct net *net = sock_net(skb->sk);
	struct nlattr *tb[IFA_MAX