#ifndef MESHLINK_H
#define MESHLINK_H
+#include <stdint.h>
#include <stdbool.h>
#include <stddef.h>
+#include <unistd.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/// The length in bytes of a signature made with meshlink_sign()
+#define MESHLINK_SIGLEN 64
/// A handle for an instance of MeshLink.
typedef struct meshlink_handle meshlink_handle_t;
/// A handle for a MeshLink node.
typedef struct meshlink_node meshlink_node_t;
+/// A handle for a MeshLink channel.
+typedef struct meshlink_channel meshlink_channel_t;
+
/// Code of most recent error encountered.
typedef enum {
- MESHLINK_OK, // Everything is fine
- MESHLINK_ENOMEM, // Out of memory
- MESHLINK_ENOENT, // Node is not known
+ MESHLINK_OK, ///< Everything is fine
+ MESHLINK_ENOMEM, ///< Out of memory
+ MESHLINK_ENOENT, ///< Node is not known
} meshlink_errno_t;
#ifndef MESHLINK_INTERNAL_H
struct meshlink_handle {
- meshlink_errno_t errno; /// Code of the last encountered error.
- const char *errstr; /// Textual representation of most recent error encountered.
+ meshlink_errno_t meshlink_errno; ///< Code of the last encountered error.
+ const char *errstr; ///< Textual representation of most recent error encountered.
};
struct meshlink_node {
- const char *name; // Textual name of this node.
- void *priv; // Private pointer which the application can set at will.
+ const char *name; ///< Textual name of this node.
+ void *priv; ///< Private pointer which the application can set at will.
+};
+
+struct meshlink_channel {
};
#endif // MESHLINK_INTERNAL_H
* but it is not a problem if it is run more than once, as long as
* the arguments given are the same.
*
+ * 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.
* @param name The name which this instance of the application will use in the mesh.
*
extern meshlink_handle_t *meshlink_open(const char *confbase, const char *name);
/// Start MeshLink.
-/** This function causes MeshLink to create a new thread, which will
- * handle all network I/O.
+/** This function causes MeshLink to open network sockets, make outgoing connections, and
+ * create a new thread, which will handle all network I/O.
*
- * @param confbase The directory in which MeshLink will store its configuration files.
+ * @param mesh A handle which represents an instance of MeshLink.
*
* @return This function will return true if MeshLink has succesfully started its thread, false otherwise.
*/
/// Stop MeshLink.
/** This function causes MeshLink to disconnect from all other nodes,
- * and shuts down its own thread.
+ * close all sockets, and shut down its own thread.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
*/
extern void meshlink_stop(meshlink_handle_t *mesh);
* and frees all memory allocated by MeshLink.
* Afterwards, the handle and any pointers to a struct meshlink_node are invalid.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
*/
extern void meshlink_close(meshlink_handle_t *mesh);
/// A callback for receiving data from the mesh.
-/** @param handle A handle which represents an instance of MeshLink.
+/** @param mesh A handle which represents an instance of MeshLink.
* @param source A pointer to a meshlink_node_t describing the source of the data.
* @param data A pointer to a buffer containing the data sent by the source.
* @param len The length of the received data.
* to hand the data over to the application's thread.
* The callback should also not block itself and return as quickly as possible.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param cb A pointer to the function which will be called when another node sends data to the local node.
*/
extern void meshlink_set_receive_cb(meshlink_handle_t *mesh, meshlink_receive_cb_t cb);
/// A callback reporting node status changes.
-/** @param handle A handle which represents an instance of MeshLink.
+/** @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.
* @param reachable True if the node is reachable, false otherwise.
*/
* to hand the data over to the application's thread.
* The callback should also not block itself and return as quickly as possible.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param cb A pointer to the function which will be called when another node's status changes.
*/
extern void meshlink_set_node_status_cb(meshlink_handle_t *mesh, meshlink_node_status_cb_t cb);
/// Severity of log messages generated by MeshLink.
typedef enum {
- MESHLINK_DEBUG, // Internal debugging messages. Only useful during application development.
- MESHLINK_INFO, // Informational messages.
- MESHLINK_WARNING, // Warnings which might indicate problems, but which are not real errors.
- MESHLINK_ERROR, // Errors which hamper correct functioning of MeshLink, without causing it to fail completely.
- MESHLINK_CRITICAL, // Critical errors which cause MeshLink to fail completely.
+ MESHLINK_DEBUG, ///< Internal debugging messages. Only useful during application development.
+ MESHLINK_INFO, ///< Informational messages.
+ MESHLINK_WARNING, ///< Warnings which might indicate problems, but which are not real errors.
+ MESHLINK_ERROR, ///< Errors which hamper correct functioning of MeshLink, without causing it to fail completely.
+ MESHLINK_CRITICAL, ///< Critical errors which cause MeshLink to fail completely.
} meshlink_log_level_t;
/// A callback for receiving log messages generated by MeshLink.
-/** @param handle A handle which represents an instance of MeshLink.
+/** @param mesh A handle which represents an instance of MeshLink.
* @param level An enum describing the severity level of the message.
* @param text A pointer to a string containing the textual log message.
*/
* to hand the data over to the application's thread.
* The callback should also not block itself and return as quickly as possible.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param level An enum describing the minimum severity level. Debugging information with a lower level will not trigger the callback.
* @param cb A pointer to the function which will be called when another node sends data to the local node.
*/
* and that there is no guarantee that the packet will arrive at the destination.
* The application should take care of getting an acknowledgement and retransmission if necessary.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param destination A pointer to a meshlink_node_t describing the destination for the data.
* @param data A pointer to a buffer containing the data to be sent to the source.
* @param len The length of the data.
/// Get a handle for a specific node.
/** This function returns a handle for the node with the given name.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param name The name of the node for which a handle is requested.
*
* @return A pointer to a meshlink_node_t which represents the requested node,
/// Get a list of all nodes.
/** This function returns a list with handles for all known nodes.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param nodes A pointer to an array of pointers to meshlink_node_t, which should be allocated by the application.
* @param nmemb The maximum number of pointers that can be stored in the nodes array.
*
- * @param return The number of known nodes. This can be larger than nmemb, in which case not all nodes were stored in the nodes array.
+ * @return The number of known nodes. This can be larger than nmemb, in which case not all nodes were stored in the nodes array.
*/
extern size_t meshlink_get_all_nodes(meshlink_handle_t *mesh, meshlink_node_t **nodes, size_t nmemb);
/** This function signs data using the local node's MeshLink key.
* The generated signature can be securely verified by other nodes.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param data A pointer to a buffer containing the data to be signed.
* @param len The length of the data to be signed.
+ * @param signature A pointer to a buffer where the signature will be stored.
+ * @param siglen The size of the signature buffer. Will be changed after the call to match the size of the signature itself.
*
- * @return This function returns a pointer to a string containing the signature, or NULL in case of an error.
- * The application should call free() after it has finished using the signature.
+ * @return This function returns true if the signature was correctly generated, false otherwise.
*/
-extern char *meshlink_sign(meshlink_handle_t *mesh, const char *data, size_t len);
+extern bool meshlink_sign(meshlink_handle_t *mesh, const void *data, size_t len, void *signature, size_t *siglen);
/// Verify the signature generated by another node of a piece of data.
/** This function verifies the signature that another node generated for a piece of data.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param source A pointer to a meshlink_node_t describing the source of the signature.
* @param data A pointer to a buffer containing the data to be verified.
* @param len The length of the data to be verified.
* @param signature A pointer to a string containing the signature.
+ * @param siglen The size of the signature.
*
* @return This function returns true if the signature is valid, false otherwise.
*/
-extern bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const char *data, size_t len, const char *signature);
+extern bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const void *data, size_t len, const void *signature, size_t siglen);
+
+/// Add an Address for the local node.
+/** This function adds an Address for the local node, which will be used for invitation URLs.
+ *
+ * @param mesh A handle which represents an instance of MeshLink.
+ * @param address A string containing the address, which can be either in numeric format or a hostname.
+ *
+ * @return This function returns true if the address was added, false otherwise.
+ */
+extern bool meshlink_add_address(meshlink_handle_t *mesh, const char *address);
/// Invite another node into the mesh.
/** This function generates an invitation that can be used by another node to join the same mesh as the local node.
* This URL should be passed by the application to the invitee in a way that no eavesdroppers can see the URL.
* The URL can only be used once, after the user has joined the mesh the URL is no longer valid.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param name The name that the invitee will use in the mesh.
*
* @return This function returns a string that contains the invitation URL.
* An invitation can only be used if the local node has never connected to other nodes before.
* After a succesfully accepted invitation, the name of the local node may have changed.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param invitation A string containing the invitation URL.
*
* @return This function returns true if the local node joined the mesh it was invited to, false otherwise.
* The application can pass it in some way to another node, which can then import it,
* granting the local node access to the other node's mesh.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
*
* @return This function returns a string that contains the exported key and addresses.
* The application should call free() after it has finished using this string.
/** This function accepts a string containing the exported public key and addresses of another node.
* By importing this data, the local node grants the other node access to its mesh.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param data A string containing the other node's exported key and addresses.
*
* @return This function returns true if the data was valid and the other node has been granted access to the mesh, false otherwise.
* The local node will drop any existing connections to that node,
* and will not send data to it nor accept any data received from it any more.
*
- * @param handle A handle which represents an instance of MeshLink.
+ * @param mesh A handle which represents an instance of MeshLink.
* @param node A pointer to a meshlink_node_t describing the node to be blacklisted.
*/
extern void meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node);
+/// A callback for accepting incoming channels.
+/** 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.
+ *
+ * @param mesh A handle which represents an instance of MeshLink.
+ * @param channel A handle for the incoming channel.
+ * @param node The node from which this channel is being initiated.
+ * @param port The port number the peer wishes to connect to.
+ * @param data A pointer to a buffer containing data already received. (Not yet used.)
+ * @param len The length of the data. (Not yet used.)
+ *
+ * @return This function should return true if the application accepts the incoming channel, false otherwise.
+ * If returning false, the channel is invalid and may not be used anymore.
+ */
+typedef bool (*meshlink_channel_accept_cb_t)(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_node_t *node, uint16_t port, const void *data, size_t len);
+
+/// A callback for receiving data from a channel.
+/** 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.
+ *
+ * @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.
+ * @param len The length of the data.
+ */
+typedef void (*meshlink_channel_receive_cb_t)(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len);
+
+/// Set the accept callback.
+/** This functions sets the callback that is called whenever another node sends data to the local 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 another node sends data to the local node.
+ */
+extern void meshlink_set_channel_accept_cb(meshlink_handle_t *mesh, meshlink_channel_accept_cb_t cb);
+
+/// Set the receive callback.
+/** This functions sets the callback that is called whenever another node sends data to the local 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 channel A handle for the channel.
+ * @param cb A pointer to the function which will be called when another node sends data to the local node.
+ */
+extern void meshlink_set_channel_receive_cb(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_channel_receive_cb_t cb);
+
+/// 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.
+ *
+ * @param mesh A handle which represents an instance of MeshLink.
+ * @param node The node to which this channel is being initiated.
+ * @param port The port number the peer wishes to connect to.
+ * @param cb A pointer to the function which will be called when the remote node sends data to the local node.
+ * @param data A pointer to a buffer containing data to already queue for sending.
+ * @param len The length of the data.
+ *
+ * @return A handle for the channel, or NULL in case of an error.
+ */
+extern meshlink_channel_t *meshlink_channel_open(meshlink_handle_t *mesh, meshlink_node_t *node, uint16_t port, meshlink_channel_receive_cb_t cb, const void *data, size_t len);
+
+/// Partially close a reliable stream channel.
+/** This shuts down the read or write side of a channel, or both, without closing the handle.
+ * It can be used to inform the remote node that the local node has finished sending all data on the channel,
+ * but still allows waiting for incoming data from the remote node.
+ *
+ * @param mesh A handle which represents an instance of MeshLink.
+ * @param channel A handle for the channel.
+ * @param direction Must be one of SHUT_RD, SHUT_WR or SHUT_RDWR.
+ */
+extern void meshlink_channel_shutdown(meshlink_handle_t *mesh, meshlink_channel_t *channel, int direction);
+
+/// Close a reliable stream channel.
+/** This informs the remote node that the local node has finished sending all data on the channel.
+ * It also causes the local node to stop accepting incoming data from the remote node.
+ * Afterwards, the channel handle is invalid and must not be used any more.
+ *
+ * @param mesh A handle which represents an instance of MeshLink.
+ * @param channel A handle for the channel.
+ */
+extern void meshlink_channel_close(meshlink_handle_t *mesh, meshlink_channel_t *channel);
+
+/// Transmit data on a channel
+/** This queues data to send to the remote node.
+ *
+ * @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.
+ * @param len The length of the data.
+ *
+ * @return The amount of data that was queued, which can be less than len, or a negative value in case of an error.
+ */
+extern ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len);
+
+#ifdef __cplusplus
+}
+#endif
+
#endif // MESHLINK_H
projects / meshlink / blobdiff