net/tipc/udp_media.c

Source file repositories/reference/linux-study-clean/net/tipc/udp_media.c

File Facts

System
Linux kernel
Corpus path
net/tipc/udp_media.c
Extension
.c
Size
22130 bytes
Lines
865
Domain
Networking Core
Bucket
Sockets, Protocols, Packet Path, And Network Policy
Inferred role
Networking Core: implementation source
Status
source implementation candidate

Why This File Exists

Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.

Dependency Surface

Detected Declarations

Annotated Snippet

struct udp_media_addr {
	__be16	proto;
	__be16	port;
	union {
		struct in_addr ipv4;
		struct in6_addr ipv6;
	};
};

/* struct udp_replicast - container for UDP remote addresses */
struct udp_replicast {
	struct udp_media_addr addr;
	struct dst_cache dst_cache;
	struct rcu_head rcu;
	struct list_head list;
};

/**
 * struct udp_bearer - ip/udp bearer data structure
 * @bearer:	associated generic tipc bearer
 * @sk:		bearer associated socket
 * @ifindex:	local address scope
 * @work:	used to schedule deferred work on a bearer
 * @rcast:	associated udp_replicast container
 */
struct udp_bearer {
	struct tipc_bearer __rcu *bearer;
	struct sock *sk;
	u32 ifindex;
	struct work_struct work;
	struct udp_replicast rcast;
};

static int tipc_udp_is_mcast_addr(struct udp_media_addr *addr)
{
	if (ntohs(addr->proto) == ETH_P_IP)
		return ipv4_is_multicast(addr->ipv4.s_addr);
#if IS_ENABLED(CONFIG_IPV6)
	else
		return ipv6_addr_is_multicast(&addr->ipv6);
#endif
	return 0;
}

/* udp_media_addr_set - convert a ip/udp address to a TIPC media address */
static void tipc_udp_media_addr_set(struct tipc_media_addr *addr,
				    struct udp_media_addr *ua)
{
	memset(addr, 0, sizeof(struct tipc_media_addr));
	addr->media_id = TIPC_MEDIA_TYPE_UDP;
	memcpy(addr->value, ua, sizeof(struct udp_media_addr));

	if (tipc_udp_is_mcast_addr(ua))
		addr->broadcast = TIPC_BROADCAST_SUPPORT;
}

/* tipc_udp_addr2str - convert ip/udp address to string */
static int tipc_udp_addr2str(struct tipc_media_addr *a, char *buf, int size)
{
	struct udp_media_addr *ua = (struct udp_media_addr *)&a->value;

	if (ntohs(ua->proto) == ETH_P_IP)
		snprintf(buf, size, "%pI4:%u", &ua->ipv4, ntohs(ua->port));
	else if (ntohs(ua->proto) == ETH_P_IPV6)
		snprintf(buf, size, "%pI6:%u", &ua->ipv6, ntohs(ua->port));
	else {
		pr_err("Invalid UDP media address\n");
		return 1;
	}

	return 0;
}

/* tipc_udp_msg2addr - extract an ip/udp address from a TIPC ndisc message */
static int tipc_udp_msg2addr(struct tipc_bearer *b, struct tipc_media_addr *a,
			     char *msg)
{
	struct udp_media_addr *ua;

	ua = (struct udp_media_addr *) (msg + TIPC_MEDIA_ADDR_OFFSET);
	if (msg[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_UDP)
		return -EINVAL;
	tipc_udp_media_addr_set(a, ua);
	return 0;
}

/* tipc_udp_addr2msg - write an ip/udp address to a TIPC ndisc message */
static int tipc_udp_addr2msg(char *msg, struct tipc_media_addr *a)
{
	memset(msg, 0, TIPC_MEDIA_INFO_SIZE);

Annotation

Implementation Notes