X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fmeshlink.h;h=06f8791334d67ec8378aa45c15fec9ad4baac1be;hb=c023ad12147aa88810629c110ea6b1ab94267196;hp=9c800ab805115866d7bf33c6604b834d52e4b8d8;hpb=ec02aca3d7888f072c5c0d52ba6b5c37ed42b69e;p=meshlink diff --git a/src/meshlink.h b/src/meshlink.h index 9c800ab8..06f87913 100644 --- a/src/meshlink.h +++ b/src/meshlink.h @@ -94,6 +94,7 @@ static const uint32_t MESHLINK_CHANNEL_RELIABLE = 1; // Data is retransmitted static const uint32_t MESHLINK_CHANNEL_ORDERED = 2; // Data is delivered in-order to the application. static const uint32_t MESHLINK_CHANNEL_FRAMED = 4; // Data is delivered in chunks of the same length as data was originally sent. static const uint32_t MESHLINK_CHANNEL_DROP_LATE = 8; // When packets are reordered, late packets are ignored. +static const uint32_t MESHLINK_CHANNEL_NO_PARTIAL = 16; // Calls to meshlink_channel_send() will either send all data or nothing. static const uint32_t MESHLINK_CHANNEL_TCP = 3; // Select TCP semantics. static const uint32_t MESHLINK_CHANNEL_UDP = 0; // Select UDP semantics. @@ -165,6 +166,27 @@ extern meshlink_open_params_t *meshlink_open_params_init(const char *confbase, c */ extern void meshlink_open_params_free(meshlink_open_params_t *params); +/// Set the network namespace MeshLink should use. +/** This function changes the open parameters to use the given netns filedescriptor. + * + * @param params A pointer to a meshlink_open_params_t which must have been created earlier with meshlink_open_params_init(). + * @param netns A filedescriptor that must point to a valid network namespace, or -1 to have MeshLink use the same namespace as the calling thread. + * + * @return This function will return true if the open parameters have been succesfully updated, false otherwise. + */ +extern bool meshlink_open_params_set_netns(meshlink_open_params_t *params, int netns); + +/// Set the encryption key MeshLink should use for local storage. +/** This function changes the open parameters to use the given key for encrypting MeshLink's own configuration files. + * + * @param params A pointer to a meshlink_open_params_t which must have been created earlier with meshlink_open_params_init(). + * @param key A pointer to a key, or NULL in case no encryption should be used. + * @param keylen The length of the given key, or 0 in case no encryption should be used. + * + * @return This function will return true if the open parameters have been succesfully updated, false otherwise. + */ +extern bool meshlink_open_params_set_storage_key(meshlink_open_params_t *params, const void *key, size_t keylen); + /// Open or create a MeshLink instance. /** This function opens or creates a MeshLink instance. * All parameters needed by MeshLink are passed via a meshlink_open_params_t struct, @@ -214,6 +236,61 @@ extern meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) */ extern meshlink_handle_t *meshlink_open(const char *confbase, const char *name, const char *appname, dev_class_t devclass); +/// Open or create a MeshLink instance that uses encrypted storage. +/** This function opens or creates a MeshLink instance. + * The state is stored in the configuration directory passed in the variable @a confbase @a. + * If the configuration directory does not exist yet, for example when it is the first time + * this instance is opened, the configuration directory will be automatically created and initialized. + * However, the parent directory should already exist, otherwise an error will be returned. + * + * The name given should be a unique identifier for this instance. + * + * This function returns a pointer to a struct meshlink_handle that will be allocated by MeshLink. + * When the application does no longer need to use this handle, it must call meshlink_close() to + * free its resources. + * + * This function does not start any network I/O yet. The application should + * first set callbacks, and then call meshlink_start(). + * + * @param confbase The directory in which MeshLink will store its configuration files. + * After the function returns, the application is free to overwrite or free @a confbase @a. + * @param name The name which this instance of the application will use in the mesh. + * After the function returns, the application is free to overwrite or free @a name @a. + * @param appname The application name which will be used in the mesh. + * After the function returns, the application is free to overwrite or free @a name @a. + * @param devclass The device class which will be used in the mesh. + * @param key A pointer to a key used to encrypt storage. + * @param keylen The length of the key in bytes. + * + * @return A pointer to a meshlink_handle_t which represents this instance of MeshLink, or NULL in case of an error. + * The pointer is valid until meshlink_close() is called. + */ +extern meshlink_handle_t *meshlink_open_encrypted(const char *confbase, const char *name, const char *appname, dev_class_t devclass, const void *key, size_t keylen); + +/// Create an ephemeral MeshLink instance that does not store any state. +/** This function creates a MeshLink instance. + * No state is ever saved, so once this instance is closed, all its state is gone. + * + * The name given should be a unique identifier for this instance. + * + * This function returns a pointer to a struct meshlink_handle that will be allocated by MeshLink. + * When the application does no longer need to use this handle, it must call meshlink_close() to + * free its resources. + * + * This function does not start any network I/O yet. The application should + * first set callbacks, and then call meshlink_start(). + * + * @param name The name which this instance of the application will use in the mesh. + * After the function returns, the application is free to overwrite or free @a name @a. + * @param appname The application name which will be used in the mesh. + * After the function returns, the application is free to overwrite or free @a name @a. + * @param devclass The device class which will be used in the mesh. + * + * @return A pointer to a meshlink_handle_t which represents this instance of MeshLink, or NULL in case of an error. + * The pointer is valid until meshlink_close() is called. + */ +extern meshlink_handle_t *meshlink_open_ephemeral(const char *name, const char *appname, dev_class_t devclass); + /// Create Sub-Mesh. /** This function causes MeshLink to open a new Sub-Mesh network * create a new thread, which will handle all network I/O. @@ -300,6 +377,26 @@ typedef void (*meshlink_receive_cb_t)(meshlink_handle_t *mesh, meshlink_node_t * */ extern void meshlink_set_receive_cb(meshlink_handle_t *mesh, meshlink_receive_cb_t cb); +/// A callback reporting the meta-connection attempt made by the host node to an another node. +/** @param mesh A handle which represents an instance of MeshLink. + * @param node A pointer to a meshlink_node_t describing the node to whom meta-connection is being tried. + * This pointer is valid until meshlink_close() is called. + */ +typedef void (*meshlink_connection_try_cb_t)(meshlink_handle_t *mesh, meshlink_node_t *node); + +/// Set the meta-connection try callback. +/** This functions sets the callback that is called whenever a connection attempt is happened to another node. + * The callback is run in MeshLink's own thread. + * It is therefore important that the callback uses apprioriate methods (queues, pipes, locking, etc.) + * to hand the data over to the application's thread. + * The callback should also not block itself and return as quickly as possible. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param cb A pointer to the function which will be called when host node attempts to make + * the connection to another node. If a NULL pointer is given, the callback will be disabled. + */ +extern void meshlink_set_connection_try_cb(meshlink_handle_t *mesh, meshlink_connection_try_cb_t cb); + /// A callback reporting node status changes. /** @param mesh A handle which represents an instance of MeshLink. * @param node A pointer to a meshlink_node_t describing the node whose status changed. @@ -441,6 +538,19 @@ extern meshlink_node_t *meshlink_get_self(meshlink_handle_t *mesh); */ extern meshlink_node_t *meshlink_get_node(meshlink_handle_t *mesh, const char *name); +/// Get a handle for a specific submesh. +/** This function returns a handle for the submesh with the given name. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param name The name of the submesh for which a handle is requested. + * After this function returns, the application is free to overwrite or free @a name @a. + * + * @return A pointer to a meshlink_submesh_t which represents the requested submesh, + * or NULL if the requested submesh does not exist. + * The pointer is guaranteed to be valid until meshlink_close() is called. + */ +extern meshlink_submesh_t *meshlink_get_submesh(meshlink_handle_t *mesh, const char *name); + /// Get the fingerprint of a node's public key. /** This function returns a fingerprint of the node's public key. * It should be treated as an opaque blob. @@ -697,7 +807,9 @@ extern int meshlink_get_port(meshlink_handle_t *mesh); * If the port is set to 0, then MeshLink will listen on a port * that is randomly assigned by the operating system every time meshlink_open() is called. * - * @return This function returns true if the port was successfully changed, false otherwise. + * @return This function returns true if the port was successfully changed + * to the desired port, false otherwise. If it returns false, there + * is no guarantee that MeshLink is listening on the old port. */ extern bool meshlink_set_port(meshlink_handle_t *mesh, int port); @@ -923,6 +1035,28 @@ extern void meshlink_set_channel_receive_cb(meshlink_handle_t *mesh, meshlink_ch */ extern void meshlink_set_channel_poll_cb(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_channel_poll_cb_t cb); +/// Set the send buffer size of a channel. +/** This function sets the desired size of the send buffer. + * The default size is 128 kB. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel. + * @param size The desired size for the send buffer. + * If a NULL pointer is given, the callback will be disabled. + */ +extern void meshlink_set_channel_sndbuf(meshlink_handle_t *mesh, meshlink_channel_t *channel, size_t size); + +/// Set the receive buffer size of a channel. +/** This function sets the desired size of the receive buffer. + * The default size is 128 kB. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel. + * @param size The desired size for the send buffer. + * If a NULL pointer is given, the callback will be disabled. + */ +extern void meshlink_set_channel_rcvbuf(meshlink_handle_t *mesh, meshlink_channel_t *channel, size_t size); + /// Open a reliable stream channel to another node. /** This function is called whenever a remote node wants to open a channel to the local node. * The application then has to decide whether to accept or reject this channel. @@ -1008,9 +1142,98 @@ extern void meshlink_channel_close(meshlink_handle_t *mesh, meshlink_channel_t * * @param len The length of the data, or 0 if there is no data to send. * * @return The amount of data that was queued, which can be less than len, or a negative value in case of an error. + * If MESHLINK_CHANNEL_NO_PARTIAL is set, then the result will either be len, + * 0 if the buffer is currently too full, or -1 if len is too big even for an empty buffer. */ extern ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len); +/// A callback for cleaning up buffers submitted for asynchronous I/O. +/** This callbacks signals that MeshLink has finished using this buffer. + * The ownership of the buffer is now back into the application's hands. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel which used this buffer. + * @param data A pointer to a buffer containing the enqueued data. + * @param len The length of the buffer. + * @param priv A private pointer which was set by the application when submitting the buffer. + */ +typedef void (*meshlink_aio_cb_t)(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len, void *priv); + +/// A callback for asynchronous I/O to and from filedescriptors. +/** This callbacks signals that MeshLink has finished using this filedescriptor. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel which used this filedescriptor. + * @param fd The filedescriptor that was used. + * @param len The length of the data that was successfully sent or received. + * @param priv A private pointer which was set by the application when submitting the buffer. + */ +typedef void (*meshlink_aio_fd_cb_t)(meshlink_handle_t *mesh, meshlink_channel_t *channel, int fd, size_t len, void *priv); + +/// Transmit data on a channel asynchronously +/** This registers a buffer that will be used to send data to the remote node. + * Multiple buffers can be registered, in which case data will be sent in the order the buffers were registered. + * While there are still buffers with unsent data, the poll callback will not be called. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel. + * @param data A pointer to a buffer containing data sent by the source, or NULL if there is no data to send. + * After meshlink_channel_aio_send() returns, the buffer may not be modified or freed by the application + * until the callback routine is called. + * @param len The length of the data, or 0 if there is no data to send. + * @param cb A pointer to the function which will be called when MeshLink has finished using the buffer. + * + * @return True if the buffer was enqueued, false otherwise. + */ +extern bool meshlink_channel_aio_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len, meshlink_aio_cb_t cb, void *priv); + +/// Transmit data on a channel asynchronously from a filedescriptor +/** This will read up to the specified length number of bytes from the given filedescriptor, and send it over the channel. + * The callback may be returned early if there is an error reading from the filedescriptor. + * While there is still with unsent data, the poll callback will not be called. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel. + * @param fd A file descriptor from which data will be read. + * @param len The length of the data, or 0 if there is no data to send. + * @param cb A pointer to the function which will be called when MeshLink has finished using the filedescriptor. + * + * @return True if the buffer was enqueued, false otherwise. + */ +extern bool meshlink_channel_aio_fd_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, int fd, size_t len, meshlink_aio_fd_cb_t cb, void *priv); + +/// Receive data on a channel asynchronously +/** This registers a buffer that will be filled with incoming channel data. + * Multiple buffers can be registered, in which case data will be received in the order the buffers were registered. + * While there are still buffers that have not been filled, the receive callback will not be called. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel. + * @param data A pointer to a buffer that will be filled with incoming data. + * After meshlink_channel_aio_receive() returns, the buffer may not be modified or freed by the application + * until the callback routine is called. + * @param len The length of the data. + * @param cb A pointer to the function which will be called when MeshLink has finished using the buffer. + * + * @return True if the buffer was enqueued, false otherwise. + */ +extern bool meshlink_channel_aio_receive(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len, meshlink_aio_cb_t cb, void *priv); + +/// Receive data on a channel asynchronously and send it to a filedescriptor +/** This will read up to the specified length number of bytes from the channel, and send it to the filedescriptor. + * The callback may be returned early if there is an error writing to the filedescriptor. + * While there is still unread data, the receive callback will not be called. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel. + * @param fd A file descriptor to which data will be written. + * @param len The length of the data. + * @param cb A pointer to the function which will be called when MeshLink has finished using the filedescriptor. + * + * @return True if the buffer was enqueued, false otherwise. + */ +extern bool meshlink_channel_aio_fd_receive(meshlink_handle_t *mesh, meshlink_channel_t *channel, int fd, size_t len, meshlink_aio_fd_cb_t cb, void *priv); + /// Get channel flags. /** This returns the flags used when opening this channel. * @@ -1021,6 +1244,28 @@ extern ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t */ extern uint32_t meshlink_channel_get_flags(meshlink_handle_t *mesh, meshlink_channel_t *channel); +/// Get the amount of bytes in the send buffer. +/** This returns the amount of bytes in the send buffer. + * These bytes have not been received by the peer yet. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel. + * + * @return The amount of un-ACKed bytes in the send buffer. + */ +extern size_t meshlink_channel_get_sendq(meshlink_handle_t *mesh, meshlink_channel_t *channel); + +/// Get the amount of bytes in the receive buffer. +/** This returns the amount of bytes in the receive buffer. + * These bytes have not been processed by the application yet. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel. + * + * @return The amount of bytes in the receive buffer. + */ +extern size_t meshlink_channel_get_recvq(meshlink_handle_t *mesh, meshlink_channel_t *channel); + /// Hint that a hostname may be found at an address /** This function indicates to meshlink that the given hostname is likely found * at the given IP address and port. @@ -1043,6 +1288,19 @@ extern void meshlink_hint_address(meshlink_handle_t *mesh, meshlink_node_t *node */ extern void meshlink_enable_discovery(meshlink_handle_t *mesh, bool enable); +/// Performs key rotation for an encrypted storage + +/** This rotates the (master) key for an encrypted storage and discards the old key + * if the call succeeded. This is an atomic call. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param key A pointer to the new key used to encrypt storage. + * @param keylen The length of the new key in bytes. + * + * @return This function returns true if the key rotation for the encrypted storage succeeds, false otherwise. + */ +extern bool meshlink_encrypted_key_rotate(meshlink_handle_t *mesh, const void *new_key, size_t new_keylen); + #ifdef __cplusplus } #endif