zephyr/include/net/net_context.h

833 lines
26 KiB
C

/** @file
* @brief Network context definitions
*
* An API for applications to define a network connection.
*/
/*
* Copyright (c) 2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef __NET_CONTEXT_H
#define __NET_CONTEXT_H
/**
* @brief Application network context
* @defgroup net_context Application network context
* @ingroup networking
* @{
*/
#include <kernel.h>
#include <atomic.h>
#include <net/net_ip.h>
#include <net/net_if.h>
#include <net/net_stats.h>
#ifdef __cplusplus
extern "C" {
#endif
/** Is this context used or not */
#define NET_CONTEXT_IN_USE BIT(0)
/** State of the context (bits 1 & 2 in the flags) */
enum net_context_state {
NET_CONTEXT_IDLE = 0,
NET_CONTEXT_UNCONNECTED = 0,
NET_CONTEXT_CONFIGURING = 1,
NET_CONTEXT_CONNECTING = 1,
NET_CONTEXT_READY = 2,
NET_CONTEXT_CONNECTED = 2,
NET_CONTEXT_LISTENING = 3,
};
/**
* The address family, connection type and IP protocol are
* stored into a bit field to save space.
*/
/** Protocol family of this connection */
#define NET_CONTEXT_FAMILY BIT(4)
/** Type of the connection (datagram / stream) */
#define NET_CONTEXT_TYPE BIT(5)
/** IP protocol (like UDP or TCP) */
#define NET_CONTEXT_PROTO BIT(6)
/** Remote address set */
#define NET_CONTEXT_REMOTE_ADDR_SET BIT(7)
struct net_context;
/**
* @typedef net_context_recv_cb_t
* @brief Network data receive callback.
*
* @details The recv callback is called after a network data packet is
* received. This callback is called by RX thread so its stack and execution
* context is used here. Keep processing in the callback minimal to reduce the
* time spent blocked while handling packets.
*
* @param context The context to use.
* @param pkt Network buffer that is received. If the pkt is not NULL,
* then the callback will own the buffer and it needs to to unref the pkt
* as soon as it has finished working with it. On EOF, pkt will be NULL.
* @param status Value is set to 0 if some data or the connection is
* at EOF, <0 if there was an error receiving data, in this case the
* pkt parameter is set to NULL.
* @param user_data The user data given in net_recv() call.
*/
typedef void (*net_context_recv_cb_t)(struct net_context *context,
struct net_pkt *pkt,
int status,
void *user_data);
/**
* @typedef net_context_send_cb_t
* @brief Network data send callback.
*
* @details The send callback is called after a network data packet is sent.
* This callback is called by TX thread so its stack and execution context is
* used here. Keep processing in the callback minimal to reduce the time spent
* blocked while handling packets.
*
* @param context The context to use.
* @param status Value is set to 0 if all data was sent ok, <0 if
* there was an error sending data. >0 amount of data that was
* sent when not all data was sent ok.
* @param token User specified value specified in net_send() call.
* @param user_data The user data given in net_send() call.
*/
typedef void (*net_context_send_cb_t)(struct net_context *context,
int status,
void *token,
void *user_data);
/**
* @typedef net_tcp_accept_cb_t
* @brief Accept callback
*
* @details The accept callback is called after a successful connection was
* established or if there was an error while we were waiting for a connection
* attempt. This callback is called by RX thread so its stack and execution
* context is used here. Keep processing in the callback minimal to reduce the
* time spent blocked while handling packets.
*
* @param context The context to use.
* @param addr The peer address.
* @param addrlen Length of the peer address.
* @param status The status code, 0 on success, < 0 otherwise
* @param user_data The user data given in net_context_accept() call.
*/
typedef void (*net_tcp_accept_cb_t)(struct net_context *new_context,
struct sockaddr *addr,
socklen_t addrlen,
int status,
void *user_data);
/**
* @typedef net_context_connect_cb_t
* @brief Connection callback.
*
* @details The connect callback is called after a connection is being
* established.
* For TCP connections, this callback is called by RX thread so its stack and
* execution context is used here. The callback is called after the TCP
* connection was established or if the connection failed. Keep processing in
* the callback minimal to reduce the time spent blocked while handling
* packets.
* For UDP connections, this callback is called immediately by
* net_context_connect() function. UDP is a connectionless protocol so the
* connection can be thought of being established immediately.
*
* @param context The context to use.
* @param status Status of the connection establishment. This is 0
* if the connection was established successfully, <0 if there was an
* error.
* @param user_data The user data given in net_context_connect() call.
*/
typedef void (*net_context_connect_cb_t)(struct net_context *context,
int status,
void *user_data);
/* The net_pkt_get_slab_func_t is here in order to avoid circular
* dependency between net_pkt.h and net_context.h
*/
/**
* @typedef net_pkt_get_slab_func_t
*
* @brief Function that is called to get the slab that is used
* for net_pkt allocations.
*
* @return Pointer to valid struct k_mem_slab instance.
*/
typedef struct k_mem_slab *(*net_pkt_get_slab_func_t)(void);
/* The net_pkt_get_pool_func_t is here in order to avoid circular
* dependency between net_pkt.h and net_context.h
*/
/**
* @typedef net_pkt_get_pool_func_t
*
* @brief Function that is called to get the pool that is used
* for net_buf allocations.
*
* @return Pointer to valid struct net_buf_pool instance.
*/
typedef struct net_buf_pool *(*net_pkt_get_pool_func_t)(void);
struct net_tcp;
struct net_conn_handle;
/**
* Note that we do not store the actual source IP address in the context
* because the address is already be set in the network interface struct.
* If there is no such source address there, the packet cannot be sent
* anyway. This saves 12 bytes / context in IPv6.
*/
struct net_context {
/** User data.
*
* First member of the structure to let users either have user data
* associated with a context, or put contexts into a FIFO.
*/
void *user_data;
/** Reference count
*/
atomic_t refcount;
/** Local IP address. Note that the values are in network byte order.
*/
struct sockaddr_ptr local;
/** Remote IP address. Note that the values are in network byte order.
*/
struct sockaddr remote;
/** Connection handle */
struct net_conn_handle *conn_handler;
/** Receive callback to be called when desired packet
* has been received.
*/
net_context_recv_cb_t recv_cb;
/** Send callback to be called when the packet has been sent
* successfully.
*/
net_context_send_cb_t send_cb;
/** Connect callback to be called when a connection has been
* established.
*/
net_context_connect_cb_t connect_cb;
#if defined(CONFIG_NET_CONTEXT_NET_PKT_POOL)
/** Get TX net_buf pool for this context.
*/
net_pkt_get_slab_func_t tx_slab;
/** Get DATA net_buf pool for this context.
*/
net_pkt_get_pool_func_t data_pool;
#endif /* CONFIG_NET_CONTEXT_NET_PKT_POOL */
#if defined(CONFIG_NET_CONTEXT_SYNC_RECV)
/**
* Semaphore to signal synchronous recv call completion.
*/
struct k_sem recv_data_wait;
#endif /* CONFIG_NET_CONTEXT_SYNC_RECV */
/** Network interface assigned to this context */
u8_t iface;
/** Flags for the context */
u8_t flags;
#if defined(CONFIG_NET_TCP)
/** TCP connection information */
struct net_tcp *tcp;
#endif /* CONFIG_NET_TCP */
#if defined(CONFIG_NET_APP)
/** net_app connection information */
void *net_app;
#endif /* CONFIG_NET_APP */
#if defined(CONFIG_NET_SOCKETS)
/** Per-socket packet or connection queues */
union {
struct k_fifo recv_q;
struct k_fifo accept_q;
};
#endif /* CONFIG_NET_SOCKETS */
};
static inline bool net_context_is_used(struct net_context *context)
{
NET_ASSERT(context);
return context->flags & NET_CONTEXT_IN_USE;
}
#define NET_CONTEXT_STATE_SHIFT 1
#define NET_CONTEXT_STATE_MASK 0x03
/**
* @brief Get state for this network context.
*
* @details This function returns the state of the context.
*
* @param context Network context.
*
* @return Network state.
*/
static inline
enum net_context_state net_context_get_state(struct net_context *context)
{
NET_ASSERT(context);
return (context->flags >> NET_CONTEXT_STATE_SHIFT) &
NET_CONTEXT_STATE_MASK;
}
/**
* @brief Set state for this network context.
*
* @details This function sets the state of the context.
*
* @param context Network context.
* @param state New network context state.
*/
static inline void net_context_set_state(struct net_context *context,
enum net_context_state state)
{
NET_ASSERT(context);
context->flags &= ~(NET_CONTEXT_STATE_MASK << NET_CONTEXT_STATE_SHIFT);
context->flags |= ((state & NET_CONTEXT_STATE_MASK) <<
NET_CONTEXT_STATE_SHIFT);
}
/**
* @brief Get address family for this network context.
*
* @details This function returns the address family (IPv4 or IPv6)
* of the context.
*
* @param context Network context.
*
* @return Network state.
*/
static inline sa_family_t net_context_get_family(struct net_context *context)
{
NET_ASSERT(context);
if (context->flags & NET_CONTEXT_FAMILY) {
return AF_INET6;
}
return AF_INET;
}
/**
* @brief Set address family for this network context.
*
* @details This function sets the address family (IPv4 or IPv6)
* of the context.
*
* @param context Network context.
* @param family Address family (AF_INET or AF_INET6)
*/
static inline void net_context_set_family(struct net_context *context,
sa_family_t family)
{
NET_ASSERT(context);
if (family == AF_INET6) {
context->flags |= NET_CONTEXT_FAMILY;
return;
}
context->flags &= ~NET_CONTEXT_FAMILY;
}
/**
* @brief Get context type for this network context.
*
* @details This function returns the context type (stream or datagram)
* of the context.
*
* @param context Network context.
*
* @return Network context type.
*/
static inline
enum net_sock_type net_context_get_type(struct net_context *context)
{
NET_ASSERT(context);
if (context->flags & NET_CONTEXT_TYPE) {
return SOCK_STREAM;
}
return SOCK_DGRAM;
}
/**
* @brief Set context type for this network context.
*
* @details This function sets the context type (stream or datagram)
* of the context.
*
* @param context Network context.
* @param type Context type (SOCK_STREAM or SOCK_DGRAM)
*/
static inline void net_context_set_type(struct net_context *context,
enum net_sock_type type)
{
NET_ASSERT(context);
if (type == SOCK_STREAM) {
context->flags |= NET_CONTEXT_TYPE;
return;
}
context->flags &= ~NET_CONTEXT_TYPE;
}
/**
* @brief Get context IP protocol for this network context.
*
* @details This function returns the context IP protocol (UDP / TCP)
* of the context.
*
* @param context Network context.
*
* @return Network context IP protocol.
*/
static inline
enum net_ip_protocol net_context_get_ip_proto(struct net_context *context)
{
NET_ASSERT(context);
if (context->flags & NET_CONTEXT_PROTO) {
return IPPROTO_TCP;
}
return IPPROTO_UDP;
}
/**
* @brief Set context IP protocol for this network context.
*
* @details This function sets the context IP protocol (UDP / TCP)
* of the context.
*
* @param context Network context.
* @param ip_proto Context IP protocol (IPPROTO_UDP or IPPROTO_TCP)
*/
static inline void net_context_set_ip_proto(struct net_context *context,
enum net_ip_protocol ip_proto)
{
NET_ASSERT(context);
if (ip_proto == IPPROTO_TCP) {
context->flags |= NET_CONTEXT_PROTO;
return;
}
context->flags &= ~NET_CONTEXT_PROTO;
}
/**
* @brief Get network interface for this context.
*
* @details This function returns the used network interface.
*
* @param context Network context.
*
* @return Context network interface if context is bind to interface,
* NULL otherwise.
*/
static inline
struct net_if *net_context_get_iface(struct net_context *context)
{
NET_ASSERT(context);
return net_if_get_by_index(context->iface);
}
/**
* @brief Set network interface for this context.
*
* @details This function binds network interface to this context.
*
* @param context Network context.
* @param iface Network interface.
*/
static inline void net_context_set_iface(struct net_context *context,
struct net_if *iface)
{
NET_ASSERT(iface);
context->iface = net_if_get_by_iface(iface);
}
/**
* @brief Get network context.
*
* @details Network context is used to define the connection 5-tuple
* (protocol, remote address, remote port, source address and source
* port). Random free port number will be assigned to source port when
* context is created. This is similar as BSD socket() function.
* The context will be created with a reference count of 1.
*
* @param family IP address family (AF_INET or AF_INET6)
* @param type Type of the socket, SOCK_STREAM or SOCK_DGRAM
* @param ip_proto IP protocol, IPPROTO_UDP or IPPROTO_TCP
* @param context The allocated context is returned to the caller.
*
* @return 0 if ok, < 0 if error
*/
int net_context_get(sa_family_t family,
enum net_sock_type type,
enum net_ip_protocol ip_proto,
struct net_context **context);
/**
* @brief Close and unref a network context.
*
* @details This releases the context. It is not possible to send or
* receive data via this context after this call. This is similar as
* BSD shutdown() function. For legacy compatibility, this function
* will implicitly decrement the reference count and possibly destroy
* the context either now or when it reaches a final state.
*
* @param context The context to be closed.
*
* @return 0 if ok, < 0 if error
*/
int net_context_put(struct net_context *context);
/**
* @brief Take a reference count to a net_context, preventing destruction
*
* @details Network contexts are not recycled until their reference
* count reaches zero. Note that this does not prevent any "close"
* behavior that results from errors or net_context_put. It simply
* prevents the context from being recycled for further use.
*
* @param context The context on which to increment the reference count
*
* @return The new reference count
*/
int net_context_ref(struct net_context *context);
/**
* @brief Decrement the reference count to a network context
*
* @details Decrements the refcount. If it reaches zero, the context
* will be recycled. Note that this does not cause any
* network-visible "close" behavior (i.e. future packets to this
* connection may see TCP RST or ICMP port unreachable responses). See
* net_context_put() for that.
*
* @param context The context on which to decrement the reference count
*
* @return The new reference count, zero if the context was destroyed
*/
int net_context_unref(struct net_context *context);
/**
* @brief Assign a socket a local address.
*
* @details This is similar as BSD bind() function.
*
* @param context The context to be assigned.
* @param addr Address to assigned.
* @param addrlen Length of the address.
*
* @return 0 if ok, < 0 if error
*/
int net_context_bind(struct net_context *context,
const struct sockaddr *addr,
socklen_t addrlen);
/**
* @brief Mark the context as a listening one.
*
* @details This is similar as BSD listen() function.
*
* @param context The context to use.
* @param backlog The size of the pending connections backlog.
*
* @return 0 if ok, < 0 if error
*/
int net_context_listen(struct net_context *context,
int backlog);
/**
* @brief Create a network connection.
*
* @details The net_context_connect function creates a network
* connection to the host specified by addr. After the
* connection is established, the user-supplied callback (cb)
* is executed. cb is called even if the timeout was set to
* K_FOREVER. cb is not called if the timeout expires.
* For datagram sockets (SOCK_DGRAM), this function only sets
* the peer address.
* This function is similar to the BSD connect() function.
*
* @param context The network context.
* @param addr The peer address to connect to.
* @param addrlen Peer address length.
* @param cb Callback function. Set to NULL if not required.
* @param timeout The timeout value for the connection. Possible values:
* * K_NO_WAIT: this function will return immediately,
* * K_FOREVER: this function will block until the
* connection is established,
* * >0: this function will wait the specified ms.
* @param user_data Data passed to the callback function.
*
* @return 0 on success.
* @return -EINVAL if an invalid parameter is passed as an argument.
* @return -ENOTSUP if the operation is not supported or implemented.
* @return -ETIMEDOUT if the connect operation times out.
*/
int net_context_connect(struct net_context *context,
const struct sockaddr *addr,
socklen_t addrlen,
net_context_connect_cb_t cb,
s32_t timeout,
void *user_data);
/**
* @brief Accept a network connection attempt.
*
* @details Accept a connection being established. This function
* will return immediately if the timeout is set to K_NO_WAIT.
* In this case the context will call the supplied callback when ever
* there is a connection established to this context. This is "a register
* handler and forget" type of call (async).
* If the timeout is set to K_FOREVER, the function will wait
* until the connection is established. Timeout value > 0, will wait as
* many ms.
* After the connection is established a caller-supplied callback is called.
* The callback is called even if timeout was set to K_FOREVER, the
* callback is called before this function will return in this case.
* The callback is not called if the timeout expires.
* This is similar as BSD accept() function.
*
* @param context The context to use.
* @param cb Caller-supplied callback function.
* @param timeout Timeout for the connection. Possible values
* are K_FOREVER, K_NO_WAIT, >0.
* @param user_data Caller-supplied user data.
*
* @return 0 if ok, < 0 if error
*/
int net_context_accept(struct net_context *context,
net_tcp_accept_cb_t cb,
s32_t timeout,
void *user_data);
/**
* @brief Send a network buffer to a peer.
*
* @details This function can be used to send network data to a peer
* connection. This function will return immediately if the timeout
* is set to K_NO_WAIT. If the timeout is set to K_FOREVER, the function
* will wait until the network buffer is sent. Timeout value > 0 will
* wait as many ms. After the network buffer is sent,
* a caller-supplied callback is called. The callback is called even
* if timeout was set to K_FOREVER, the callback is called
* before this function will return in this case. The callback is not
* called if the timeout expires. For context of type SOCK_DGRAM,
* the destination address must have been set by the call to
* net_context_connect().
* This is similar as BSD send() function.
*
* @param pkt The network buffer to send.
* @param cb Caller-supplied callback function.
* @param timeout Timeout for the connection. Possible values
* are K_FOREVER, K_NO_WAIT, >0.
* @param token Caller specified value that is passed as is to callback.
* @param user_data Caller-supplied user data.
*
* @return 0 if ok, < 0 if error
*/
int net_context_send(struct net_pkt *pkt,
net_context_send_cb_t cb,
s32_t timeout,
void *token,
void *user_data);
/**
* @brief Send a network buffer to a peer specified by address.
*
* @details This function can be used to send network data to a peer
* specified by address. This variant can only be used for datagram
* connections of type SOCK_DGRAM. This function will return immediately
* if the timeout is set to K_NO_WAIT. If the timeout is set to K_FOREVER,
* the function will wait until the network buffer is sent. Timeout
* value > 0 will wait as many ms. After the network buffer
* is sent, a caller-supplied callback is called. The callback is called
* even if timeout was set to K_FOREVER, the callback is called
* before this function will return. The callback is not called if the
* timeout expires.
* This is similar as BSD sendto() function.
*
* @param pkt The network buffer to send.
* @param dst_addr Destination address. This will override the address
* already set in network buffer.
* @param addrlen Length of the address.
* @param cb Caller-supplied callback function.
* @param timeout Timeout for the connection. Possible values
* are K_FOREVER, K_NO_WAIT, >0.
* @param token Caller specified value that is passed as is to callback.
* @param user_data Caller-supplied user data.
*
* @return 0 if ok, < 0 if error
*/
int net_context_sendto(struct net_pkt *pkt,
const struct sockaddr *dst_addr,
socklen_t addrlen,
net_context_send_cb_t cb,
s32_t timeout,
void *token,
void *user_data);
/**
* @brief Receive network data from a peer specified by context.
*
* @details This function can be used to register a callback function
* that is called by the network stack when network data has been received
* for this context. As this function registers a callback, then there
* is no need to call this function multiple times if timeout is set to
* K_NO_WAIT.
* If callback function or user data changes, then the function can be called
* multiple times to register new values.
* This function will return immediately if the timeout is set to K_NO_WAIT.
* If the timeout is set to K_FOREVER, the function will wait until the
* network buffer is received. Timeout value > 0 will wait as many ms.
* After the network buffer is received, a caller-supplied callback is
* called. The callback is called even if timeout was set to K_FOREVER,
* the callback is called before this function will return in this case.
* The callback is not called if the timeout expires. The timeout functionality
* can be compiled out if synchronous behavior is not needed. The sync call
* logic requires some memory that can be saved if only async way of call is
* used. If CONFIG_NET_CONTEXT_SYNC_RECV is not set, then the timeout parameter
* value is ignored.
* This is similar as BSD recv() function.
* Note that net_context_bind() should be called before net_context_recv().
* Default random port number is assigned to local port. Only bind() will
* update connection information from context. If recv() is called before
* bind() call, it may refuse to bind to a context which already has
* a connection associated.
*
* @param context The network context to use.
* @param cb Caller-supplied callback function.
* @param timeout Caller-supplied timeout. Possible values
* are K_FOREVER, K_NO_WAIT, >0.
* @param user_data Caller-supplied user data.
*
* @return 0 if ok, < 0 if error
*/
int net_context_recv(struct net_context *context,
net_context_recv_cb_t cb,
s32_t timeout,
void *user_data);
/**
* @brief Update TCP receive window for context.
*
* @details This function should be used by an application which
* doesn't fully process incoming data in its receive callback,
* but for example, queues it. In this case, receive callback
* should decrease the window (call this function with a negative
* value) by the size of queued data, and function(s) which dequeue
* data - with positive value corresponding to the dequeued size.
* For example, if receive callback gets a packet with the data
* size of 256 and queues it, it should call this function with
* delta of -256. If a function extracts 10 bytes of the queued
* data, it should call it with delta of 10.
*
* @param context The TCP network context to use.
* @param delta Size, in bytes, by which to increase TCP receive
* window (negative value to decrease).
*
* @return 0 if ok, < 0 if error
*/
int net_context_update_recv_wnd(struct net_context *context,
s32_t delta);
/**
* @typedef net_context_cb_t
* @brief Callback used while iterating over network contexts
*
* @param context A valid pointer on current network context
* @param user_data A valid pointer on some user data or NULL
*/
typedef void (*net_context_cb_t)(struct net_context *context, void *user_data);
/**
* @brief Go through all the network connections and call callback
* for each network context.
*
* @param cb User-supplied callback function to call.
* @param user_data User specified data.
*/
void net_context_foreach(net_context_cb_t cb, void *user_data);
/**
* @brief Set custom network buffer pools for context send operations
*
* Set custom network buffer pools used by the IP stack to allocate
* network buffers used by the context when sending data to the
* network. Using dedicated buffers may help make send operations on
* a given context more reliable, e.g. not be subject to buffer
* starvation due to operations on other network contexts. Buffer pools
* are set per context, but several contexts may share the same buffers.
* Note that there's no support for per-context custom receive packet
* pools.
*
* @param context Context that will use the given net_buf pools.
* @param tx_pool Pointer to the function that will return TX pool
* to the caller. The TX pool is used when sending data to network.
* There is one TX net_pkt for each network packet that is sent.
* @param data_pool Pointer to the function that will return DATA pool
* to the caller. The DATA pool is used to store data that is sent to
* the network.
*/
#if defined(CONFIG_NET_CONTEXT_NET_PKT_POOL)
static inline void net_context_setup_pools(struct net_context *context,
net_pkt_get_slab_func_t tx_slab,
net_pkt_get_pool_func_t data_pool)
{
NET_ASSERT(context);
context->tx_slab = tx_slab;
context->data_pool = data_pool;
}
#else
#define net_context_setup_pools(context, tx_pool, data_pool)
#endif
#ifdef __cplusplus
}
#endif
/**
* @}
*/
#endif /* __NET_CONTEXT_H */