+/****f* silccore/SilcPacketAPI/silc_packet_stream_get_stream
+ *
+ * SYNOPSIS
+ *
+ * SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
+ *
+ * DESCRIPTION
+ *
+ * Returns the actual stream that is associated with the packet stream
+ * `stream'. The caller must not free the returned stream. The returned
+ * stream is the same pointer that was set for silc_packet_stream_create.
+ * This function could be used for example when an error callback is
+ * called by the packet engine to retrieve the actual lower level error
+ * from the stream.
+ *
+ ***/
+SilcStream silc_packet_stream_get_stream(SilcPacketStream stream);
+
+/****f* silccore/SilcPacketAPI/silc_packet_stream_link
+ *
+ * SYNOPSIS
+ *
+ * SilcBool silc_packet_stream_link(SilcPacketStream stream,
+ * SilcPacketCallbacks *callbacks,
+ * void *callback_context,
+ * int priority, ...);
+ *
+ * DESCRIPTION
+ *
+ * Links the packet processing callbacks indicated by `callbacks' into
+ * the packet stream indicated by `stream' with priority `priority' for
+ * the packet types given in the variable argument list. This function
+ * can be used to link to the packet stream for specific packet types
+ * and receive them in the specified callbacks. This way, a third party,
+ * for example some library may attach itself into the packet stream
+ * and receive and process certain packets. The variable argument
+ * list is ended with -1. To link to receive all packets use
+ * SILC_PACKET_ANY.
+ *
+ * The default packet processing callbacks given as argument to the
+ * silc_packet_engine_start has the priority 0. Any priority higher
+ * than 0 will then take precedence over the default callbacks. Any
+ * priority lower than 0 (negative value) will be processed after the
+ * default callbacks.
+ *
+ * Note that setting only the 'packet_receive' callback in the `callbacks'
+ * is required.
+ *
+ * EXAMPLE
+ *
+ * // Link to this packet stream, with high priority, for
+ * // SILC_PACKET_CONNECTION_AUTH and SILC_PACKET_CONNECTION_AUTH_REQUEST
+ * // packets. We don't care about other packets.
+ * silc_packet_stream_link(stream, our_callbacks, our_context,
+ * 1000000, SILC_PACKET_CONNECTION_AUTH,
+ * SILC_PACKET_CONNECTION_AUTH_REQUEST, -1);
+ *
+ ***/
+SilcBool silc_packet_stream_link(SilcPacketStream stream,
+ const SilcPacketCallbacks *callbacks,
+ void *callback_context,
+ int priority, ...);
+
+/****f* silccore/SilcPacketAPI/silc_packet_stream_unlink
+ *
+ * SYNOPSIS
+ *
+ * void silc_packet_stream_unlink(SilcPacketStream stream,
+ * SilcPacketCallbacks *callbacks,
+ * void *callback_context);
+ *
+ * DESCRIPTION
+ *
+ * Unlinks the `callbacks' with `callback_context' from the packet stream
+ * indicated by `stream'. This function must be called for the callbacks
+ * that was linked to `stream' when they are not needed anymore.
+ *
+ ***/
+void silc_packet_stream_unlink(SilcPacketStream stream,
+ const SilcPacketCallbacks *callbacks,
+ void *callback_context);
+
+/****f* silccore/SilcPacketAPI/SilcPacketWrapCoder
+ *
+ * SYNOPSIS
+ *
+ * typedef SilcBool (*SilcPacketWrapCoder)(SilcStream stream,
+ * SilcStreamStatus status,
+ * SilcBuffer buffer,
+ * void *context);
+ *
+ * DESCRIPTION
+ *
+ * The encoder/decoder callback for silc_packet_stream_wrap. If the
+ * `status' is SILC_STREAM_CAN_WRITE then additional data can be added
+ * to `buffer'. It is added before the data that is written with
+ * silc_stream_write. The silc_buffer_enlarge should be called to verify
+ * there is enough room in `buffer' before adding data to it. The `buffer'
+ * must not be freed.
+ *
+ * If the `status' is SILC_STREAM_CAN_READ then data from the `buffer'
+ * may be read before it is passed to readed when silc_stream_read is
+ * called. The `buffer' may be advanced also to hide data in it.
+ *
+ * This function returns FALSE in case of error.
+ *
+ ***/
+typedef SilcBool (*SilcPacketWrapCoder)(SilcStream stream,
+ SilcStreamStatus status,
+ SilcBuffer buffer,
+ void *context);
+
+/****f* silccore/SilcPacketAPI/silc_packet_stream_wrap
+ *
+ * SYNOPSIS
+ *
+ * SilcStream silc_packet_stream_wrap(SilcPacketStream stream,
+ * SilcPacketType type,
+ * SilcPacketFlags flags,
+ * SilcBool blocking_mode,
+ * SilcPacketWrapCoder coder,
+ * void *context);
+ *
+ * DESCRIPTION
+ *
+ * Wraps the packet stream indicated by `stream' into a SilcStream for
+ * the packet type indicated by `type' with packet flags indicated by
+ * `flags'. The returned SilcStream can be used to read and write the
+ * specified SILC packets with the specified packet flags, by calling
+ * silc_stream_read and silc_stream_write, respectively. The returned
+ * stream can be destroyed by calling silc_stream_destroy. It does not
+ * destroy the wrapped packet stream.
+ *
+ * If the `blocking_mode' mode is TRUE then the silc_stream_read and
+ * silc_stream_write may block the calling process or thread until SILC
+ * packet is read or written. If it is FALSE the stream is in non-blocking
+ * mode and the calls never block. The returned stream is thread-safe and
+ * packets may be read and written in multi-threaded environment.
+ *
+ * In non-blocking mode the silc_stream_set_notifier must be called before
+ * the returned stream can be used to read packets. The stream status
+ * SILC_STREAM_CAN_READ will be returned to the notifier callback to
+ * indicate that a packet is ready for reading. Calling silc_stream_read
+ * once returns one complete SILC packet data payload (which is of type of
+ * `type').
+ *
+ * The `coder' is optional encoder/decoder callback which the packet engine
+ * will call if it is non-NULL. It can be used to encode additional data
+ * into each packet when silc_stream_write is called or decode data before
+ * it is passed to reader when silc_stream_read is called. The `context'
+ * is passed to `coder'.
+ *
+ * The returned SilcStream can be used as any normal stream and all
+ * SilcStream API functions may be used with the stream. This returns
+ * NULL on error.
+ *
+ ***/
+SilcStream silc_packet_stream_wrap(SilcPacketStream stream,
+ SilcPacketType type,
+ SilcPacketFlags flags,
+ SilcBool blocking_mode,
+ SilcPacketWrapCoder coder,
+ void *context);
+
+/****f* silccore/SilcPacketAPI/silc_packet_stream_is_udp
+ *
+ * SYNOPSIS
+ *
+ * SilcBool silc_packet_stream_is_udp(SilcPacketStream stream);
+ *
+ * DESCRIPTION
+ *
+ * Returns TRUE if the packet stream indicated by `stream' is using
+ * UDP transport.
+ *
+ ***/
+SilcBool silc_packet_stream_is_udp(SilcPacketStream stream);
+
+/****f* silccore/SilcPacketAPI/silc_packet_get_sender
+ *
+ * SYNOPSIS
+ *
+ * SilcBool silc_packet_get_sender(SilcPacket packet,
+ * const char **sender_ip,
+ * SilcUInt16 *sender_port);
+ *
+ * DESCRIPTION
+ *
+ * Returns the packet sender's IP address and port from UDP packet
+ * indicated by `packet'. This can be called only from the packet
+ * callback to retrieve the information of the packet's sender. Returns
+ * FALSE if the information is not available.
+ *
+ ***/
+SilcBool silc_packet_get_sender(SilcPacket packet,
+ const char **sender_ip,
+ SilcUInt16 *sender_port);
+
+/****f* silccore/SilcPacketAPI/silc_packet_stream_ref
+ *
+ * SYNOPSIS
+ *
+ * void silc_packet_stream_ref(SilcPacketStream stream);
+ *
+ * DESCRIPTION
+ *
+ * Increase reference counter for the stream indicated by `stream'. This
+ * can be used to take a reference for the stream. To unreference the
+ * stream call silc_packet_stream_unref function.
+ *
+ ***/
+void silc_packet_stream_ref(SilcPacketStream stream);
+
+/****f* silccore/SilcPacketAPI/silc_packet_stream_unref
+ *
+ * SYNOPSIS
+ *
+ * void silc_packet_stream_unref(SilcPacketStream stream);
+ *
+ * DESCRIPTION
+ *
+ * Decrease reference counter for the stream indicated by `stream'. If
+ * the counter hits zero the stream will be destroyed automatically.
+ *
+ ***/
+void silc_packet_stream_unref(SilcPacketStream stream);
+
+/****f* silccore/SilcPacketAPI/silc_packet_get_engine
+ *
+ * SYNOPSIS
+ *
+ * SilcPacketEngine silc_packet_get_engine(SilcPacketStream stream);
+ *
+ * DESCRIPTION
+ *
+ * Returns the packet engine from the `stream'.
+ *
+ ***/
+SilcPacketEngine silc_packet_get_engine(SilcPacketStream stream);
+
+/****f* silccore/SilcPacketAPI/silc_packet_set_context
+ *
+ * SYNOPSIS
+ *
+ * void silc_packet_set_context(SilcPacketStream stream,
+ * void *stream_context);
+ *
+ * DESCRIPTION
+ *
+ * Sets a stream specific context to the stream. The context will
+ * be delivered to all callback functions, and it can be retrieved by
+ * calling silc_packet_get_context function as well. Note that this is
+ * separate packet stream specific context, and not the same as
+ * `callback_context' in silc_packet_engine_start. Both will be delivered
+ * to the callbacks, and this context as the `stream_context' argument.
+ *
+ ***/
+void silc_packet_set_context(SilcPacketStream stream, void *stream_context);
+
+/****f* silccore/SilcPacketAPI/silc_packet_get_context
+ *
+ * SYNOPSIS
+ *
+ * void *silc_packet_get_context(SilcPacketStream stream);
+ *
+ * DESCRIPTION
+ *
+ * Returns the current set application context, or NULL if none is set.
+ *
+ ***/
+void *silc_packet_get_context(SilcPacketStream stream);
+
+/****f* silccore/SilcPacketAPI/silc_packet_set_keys
+ *
+ * SYNOPSIS
+ *
+ * void silc_packet_set_keys(SilcPacketStream stream, SilcCipher send_key,
+ * SilcCipher receive_key, SilcHmac send_hmac,
+ * SilcHmac receive_hmac, SilcBool rekey);
+ *
+ * DESCRIPTION
+ *
+ * Set ciphers and HMACs to be used to encrypt sent packets, and decrypt
+ * received packets. This can be called multiple times to change the
+ * ciphers and HMACs.
+ *
+ * If the `rekey' is TRUE this function will send SILC_PACKET_REKEY_DONE
+ * to the `stream' and will set the new keys. If it is FALSE the keys
+ * are changed but the packet is not changed.
+ *
+ * When changing keys the old cipher and HMACs will be freed. If the keys
+ * are not set at all, packets will not be encrypted or decrypted.
+ *
+ ***/
+SilcBool silc_packet_set_keys(SilcPacketStream stream, SilcCipher send_key,
+ SilcCipher receive_key, SilcHmac send_hmac,
+ SilcHmac receive_hmac, SilcBool rekey);
+
+/****f* silccore/SilcPacketAPI/silc_packet_get_keys
+ *
+ * SYNOPSIS
+ *
+ * SilcBool silc_packet_get_keys(SilcPacketStream stream,
+ * SilcCipher *send_key,
+ * SilcCipher *receive_key,
+ * SilcHmac *send_hmac,
+ * SilcHmac *receive_hmac);
+ *
+ * DESCRIPTION
+ *
+ * Returns the pointers of current ciphers and HMACs from the `stream'.
+ * Returns FALSE if keys are not set.
+ *
+ ***/
+SilcBool silc_packet_get_keys(SilcPacketStream stream,
+ SilcCipher *send_key, SilcCipher *receive_key,
+ SilcHmac *send_hmac, SilcHmac *receive_hmac);
+
+/****f* silccore/SilcPacketAPI/silc_packet_set_ids
+ *
+ * SYNOPSIS
+ *
+ * SilcBool silc_packet_set_ids(SilcPacketStream stream,
+ * SilcIdType src_id_type, const void *src_id
+ * SilcIdType dst_id_type, const void *dst_id);
+ *
+ * DESCRIPTION
+ *
+ * Set the source ID and destination ID to be used when sending packets to
+ * this packet stream. The IDs to be used for a packet stream can be
+ * overridden when sending packets. However, if the IDs do not ever change
+ * for the packet stream it is recommended they are set using this function.
+ * In this case they can be omitted when sending packets to the stream.
+ * It is also possible to set only source or destination ID.
+ *
+ ***/
+SilcBool silc_packet_set_ids(SilcPacketStream stream,
+ SilcIdType src_id_type, const void *src_id,
+ SilcIdType dst_id_type, const void *dst_id);
+
+/****f* silccore/SilcPacketAPI/silc_packet_get_ids
+ *
+ * SYNOPSIS
+ *
+ * SilcBool silc_packet_get_ids(SilcPacketStream stream,
+ * SilcBool *src_id_set, SilcID *src_id,
+ * SilcBool *dst_id_set, SilcID *dst_id);
+ *
+ * DESCRIPTION
+ *
+ * Returns source and destination IDs from the packet stream. The
+ * `src_id_set' is set to TRUE if the source ID was returned. The
+ * `dst_id_set' is set to TRUE if the destination ID was returned.
+ *
+ ***/
+SilcBool silc_packet_get_ids(SilcPacketStream stream,
+ SilcBool *src_id_set, SilcID *src_id,
+ SilcBool *dst_id_set, SilcID *dst_id);
+
+/****f* silccore/SilcPacketAPI/silc_packet_set_sid
+ *
+ * SYNOPSIS
+ *
+ * SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
+ *
+ * DESCRIPTION
+ *
+ * Sets new Security ID to the packet stream indicated by `stream'. This
+ * is called only if the IV Included property was set to the stream
+ * by calling silc_packet_stream_set_iv_included. This function sets
+ * new Security ID to the stream which is then included in the ciphertext
+ * of a packet. The `sid' must be 0 when it is set for the very first
+ * time and must be increased by one after each rekey. This function must
+ * be called every time new keys are added to the stream after a rekey.
+ *
+ * If this function is called when the IV Included property has not been
+ * set to the stream the `sid' will be ignored. Returns FALSE if the
+ * IV Included has not been set, TRUE otherwise.
+ *
+ ***/
+SilcBool silc_packet_set_sid(SilcPacketStream stream, SilcUInt8 sid);
+
+/****f* silccore/SilcPacketAPI/silc_packet_send
+ *
+ * SYNOPSIS
+ *
+ * SilcBool silc_packet_send(SilcPacketStream stream,
+ * SilcPacketType type, SilcPacketFlags flags,
+ * const unsigned char *data,
+ * SilcUInt32 data_len);
+ *
+ * DESCRIPTION
+ *
+ * Send `data' of length of `data_len' to the packet stream indicated by
+ * `stream'. If ciphers and HMACs were set using silc_packet_set_keys
+ * the packet will be encrypted and MAC will be computed for it. If
+ * silc_packet_set_ids was used to set source and destination ID for the
+ * packet stream those IDs are used in the packet. If IDs have not been
+ * set and they need to be provided then silc_packet_send_ext function
+ * should be used. Otherwise, the packet will not have IDs set at all.
+ * Returns FALSE if packet could not be sent.
+ *
+ ***/
+SilcBool silc_packet_send(SilcPacketStream stream,
+ SilcPacketType type, SilcPacketFlags flags,
+ const unsigned char *data, SilcUInt32 data_len);
+
+/****f* silccore/SilcPacketAPI/silc_packet_send_ext
+ *
+ * SYNOPSIS
+ *
+ * SilcBool
+ * silc_packet_send_ext(SilcPacketStream stream,
+ * SilcPacketType type, SilcPacketFlags flags,
+ * SilcIdType src_id_type, void *srd_id,
+ * SilcIdType dst_id_type, void *dst_id,
+ * const unsigned char *data, SilcUInt32 data_len,
+ * SilcCipher cipher, SilcHmac hmac);
+ *
+ * DESCRIPTION
+ *
+ * Same as silc_packet_send but with this function different sending
+ * parameters can be sent as argument. This function can be used to
+ * set specific IDs, cipher and HMAC to be used in packet sending,
+ * instead of the ones saved in the `stream'. If any of the extra
+ * pointers are NULL, default values set to the stream will apply.
+ *
+ ***/
+SilcBool silc_packet_send_ext(SilcPacketStream stream,
+ SilcPacketType type, SilcPacketFlags flags,
+ SilcIdType src_id_type, void *src_id,
+ SilcIdType dst_id_type, void *dst_id,
+ const unsigned char *data, SilcUInt32 data_len,
+ SilcCipher cipher, SilcHmac hmac);
+
+/****f* silccore/SilcPacketAPI/silc_packet_send_va
+ *
+ * SYNOPSIS
+ *
+ * SilcBool silc_packet_send_va(SilcPacketStream stream,
+ * SilcPacketType type,
+ * SilcPacketFlags flags, ...);
+ *
+ * DESCRIPTION
+ *
+ * Same as silc_packet_send but takes the data in as variable argument
+ * formatted buffer (see silcbuffmt.h). The arguments must be ended
+ * with SILC_STR_END. Returns FALSE if packet could not be sent or
+ * the buffer could not be formatted.
+ *
+ * EXAMPLE
+ *
+ * // Send NEW_CLIENT packet
+ * silc_packet_send_va(stream, SILC_PACKET_NEW_CLIENT, 0,
+ * SILC_STR_UI_SHORT(username_len),
+ * SILC_STR_DATA(username, username_len),
+ * SILC_STR_UI_SHORT(realname_len),
+ * SILC_STR_DATA(realname, realname_len),
+ * SILC_STR_END);
+ *
+ ***/
+SilcBool silc_packet_send_va(SilcPacketStream stream,
+ SilcPacketType type, SilcPacketFlags flags, ...);
+
+/****f* silccore/SilcPacketAPI/silc_packet_send_va_ext
+ *
+ * SYNOPSIS
+ *
+ * SilcBool
+ * silc_packet_send_va_ext(SilcPacketStream stream,
+ * SilcPacketType type, SilcPacketFlags flags,
+ * SilcIdType src_id_type, void *srd_id,
+ * SilcIdType dst_id_type, void *dst_id,
+ * SilcCipher cipher, SilcHmac hmac, ...);
+ *
+ * DESCRIPTION
+ *
+ * Same as silc_packet_send_va but with this function different sending
+ * parameters can be sent as argument. This function can be used to
+ * set specific IDs, cipher and HMAC to be used in packet sending,
+ * instead of the ones saved in the `stream'. If any of the extra
+ * pointers are NULL, default values set to the stream will apply.
+ *
+ ***/
+SilcBool silc_packet_send_va_ext(SilcPacketStream stream,
+ SilcPacketType type, SilcPacketFlags flags,
+ SilcIdType src_id_type, void *src_id,
+ SilcIdType dst_id_type, void *dst_id,
+ SilcCipher cipher, SilcHmac hmac, ...);
+
+/****f* silccore/SilcPacketAPI/silc_packet_wait_init
+ *
+ * SYNOPSIS
+ *
+ * void *silc_packet_wait_init(SilcPacketStream stream,
+ * const SilcID *source_id, ...);
+ *
+ * DESCRIPTION
+ *
+ * Initializes a packet waiter for the packet stream `stream' and
+ * for the variable argument list of packet types. The function
+ * silc_packet_wait can be used to block the thread until a packet
+ * has been received.
+ *
+ * This function is used to initialize the waiting and to give the list
+ * of packet types that caller wish to receive. The variable argument
+ * list must end with -1. To receive all packets use SILC_PACKET_ANY.
+ * If the `source_id' is non-NULL then only packets of the specified
+ * type from the specified `source_id' are received. If it is NULL
+ * then the packet source is ignored.
+ *
+ * Returns a context that must be given to the silc_packet_wait function
+ * as argument. Returns NULL on error. To uninitialize the waiting
+ * call silc_packet_wait_uninit.
+ *
+ * NOTES
+ *
+ * Note that packets may be available immediately after calling this
+ * function and they will be buffered, until silc_packet_wait is called.
+ *
+ * EXAMPLE
+ *
+ * void *waiter;
+ *
+ * // Will wait for private message packets
+ * waiter = silc_packet_wait_init(stream, NULL,
+ * SILC_PACKET_PRIVATE_MESSAGE, -1);
+ *
+ ***/
+void *silc_packet_wait_init(SilcPacketStream stream,
+ const SilcID *source_id, ...);
+
+/****f* silccore/SilcPacketAPI/silc_packet_wait_uninit
+ *
+ * SYNOPSIS
+ *
+ * void silc_packet_wait_uninit(void *waiter, SilcPacketStream stream);
+ *
+ * DESCRIPTION
+ *
+ * Uninitializes the waiting context. This may be called also from
+ * another thread while other thread is waiting for packets. This will
+ * inform the waiting thread to stop waiting.
+ *
+ ***/
+void silc_packet_wait_uninit(void *waiter, SilcPacketStream stream);
+
+/****f* silccore/SilcPacketAPI/silc_packet_wait
+ *
+ * SYNOPSIS
+ *
+ * int silc_packet_wait(void *waiter, int timeout,
+ * SilcPacket *return_packet)
+ *
+ * DESCRIPTION
+ *
+ * A special function that can be used to wait for a packet to arrive.
+ * This function will block the calling process or thread until either
+ * a packet is received into the `return_packet' pointer or the specified
+ * timeout value `timeout', which is in milliseconds, will expire. If
+ * the timeout is 0, no timeout exist. Before calling this function the
+ * silc_packet_wait_init must be called. The caller is responsible for
+ * freeing the returned packet with silc_packet_free.
+ *
+ * This function can be used for example from a thread that wants to
+ * block until SILC packet has been received.
+ *
+ * Returns 1 when packet was received, 0 if timeout occurred and -1 if
+ * error occurred.
+ *
+ * EXAMPLE
+ *
+ * static int foo_read_data(FooContext c)
+ * {
+ * SilcPacket packet;
+ * void *waiter;
+ * ...
+ *
+ * // Will wait for private message packets
+ * if (c->initialized == FALSE) {
+ * waiter = silc_packet_wait_init(stream,
+ * SILC_PACKET_PRIVATE_MESSAGE, -1);
+ * c->initialized = TRUE;
+ * }
+ *
+ * ...
+ * // Wait here until private message packet is received
+ * if ((silc_packet_wait(waiter, 0, &packet)) < 0)
+ * return -1;
+ *
+ * ... process packet ...
+ *
+ * return 1;
+ * }
+ *
+ ***/
+int silc_packet_wait(void *waiter, int timeout, SilcPacket *return_packet);
+
+/****f* silccore/SilcPacketAPI/silc_packet_free
+ *
+ * SYNOPSIS
+ *
+ * void silc_packet_free(SilcPacket packet);
+ *
+ * DESCRIPTION
+ *
+ * This function is used to free the SilcPacket pointer that application
+ * receives in the SilcPacketReceive callback. Application must free
+ * the packet if it takes it in to processing.
+ *
+ ***/
+void silc_packet_free(SilcPacket packet);
+
+#endif /* SILCPACKET_H */