X-Git-Url: http://git.meshlink.io/?p=meshlink;a=blobdiff_plain;f=src%2Fmeshlink.h;h=43d269cea76492134c08e4c8ffd9684a69502e52;hp=6858b5bc9d889f80b07331edf7fcc36106632114;hb=ecfe7cbbe08dc99ba6f329ad66bb8ee09ce9539b;hpb=f416117836dc944822cac06efb54377fb21ee66f diff --git a/src/meshlink.h b/src/meshlink.h index 6858b5bc..43d269ce 100644 --- a/src/meshlink.h +++ b/src/meshlink.h @@ -1,6 +1,9 @@ +#ifndef MESHLINK_H +#define MESHLINK_H + /* meshlink.h -- MeshLink API - Copyright (C) 2014 Guus Sliepen + Copyright (C) 2014-2019 Guus Sliepen This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -17,16 +20,13 @@ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ -#ifndef MESHLINK_H -#define MESHLINK_H - #include #include #include #include #if defined(_WIN32) -#include +#include #else #include #include @@ -37,10 +37,10 @@ extern "C" { #endif /// The length in bytes of a signature made with meshlink_sign() -#define MESHLINK_SIGLEN (64) +#define MESHLINK_SIGLEN (64ul) // The maximum length of fingerprints -#define MESHLINK_FINGERPRINTLEN (64) +#define MESHLINK_FINGERPRINTLEN (64ul) /// A handle for an instance of MeshLink. typedef struct meshlink_handle meshlink_handle_t; @@ -51,48 +51,80 @@ typedef struct meshlink_node meshlink_node_t; /// A handle for a MeshLink channel. typedef struct meshlink_channel meshlink_channel_t; +/// A struct containing all parameters used for opening a mesh. +typedef struct meshlink_open_params meshlink_open_params_t; + +/// A handle for a MeshLink sub-mesh. +typedef struct meshlink_submesh meshlink_submesh_t; + /// Code of most recent error encountered. typedef enum { - MESHLINK_OK, ///< Everything is fine - MESHLINK_EINVAL, ///< Invalid parameter(s) to function call - MESHLINK_ENOMEM, ///< Out of memory - MESHLINK_ENOENT, ///< Node is not known - MESHLINK_EEXIST, ///< Node already exists + MESHLINK_OK, ///< Everything is fine + MESHLINK_EINVAL, ///< Invalid parameter(s) to function call + MESHLINK_ENOMEM, ///< Out of memory + MESHLINK_ENOENT, ///< Node is not known + MESHLINK_EEXIST, ///< Node already exists MESHLINK_EINTERNAL, ///< MeshLink internal error - MESHLINK_ERESOLV, ///< MeshLink could not resolve a hostname - MESHLINK_ESTORAGE, ///< MeshLink coud not load or write data from/to disk - MESHLINK_ENETWORK, ///< MeshLink encountered a network error - MESHLINK_EPEER, ///< A peer caused an error + MESHLINK_ERESOLV, ///< MeshLink could not resolve a hostname + MESHLINK_ESTORAGE, ///< MeshLink could not load or write data from/to disk + MESHLINK_ENETWORK, ///< MeshLink encountered a network error + MESHLINK_EPEER, ///< A peer caused an error + MESHLINK_ENOTSUP, ///< The operation is not supported in the current configuration of MeshLink + MESHLINK_EBUSY ///< The MeshLink instance is already in use by another process } meshlink_errno_t; -// Device class +/// Device class typedef enum { - BACKBONE = 1, - STATIONARY = 2, - PORTABLE = 3 -} dclass_t; + DEV_CLASS_BACKBONE = 0, + DEV_CLASS_STATIONARY = 1, + DEV_CLASS_PORTABLE = 2, + DEV_CLASS_UNKNOWN = 3, + _DEV_CLASS_MAX = 3 +} dev_class_t; + +/// Invitation flags +static const uint32_t MESHLINK_INVITE_LOCAL = 1; // Only use local addresses in the URL +static const uint32_t MESHLINK_INVITE_PUBLIC = 2; // Only use public or canonical addresses in the URL +static const uint32_t MESHLINK_INVITE_IPV4 = 4; // Only use IPv4 addresses in the URL +static const uint32_t MESHLINK_INVITE_IPV6 = 8; // Only use IPv6 addresses in the URL +static const uint32_t MESHLINK_INVITE_NUMERIC = 16; // Don't look up hostnames + +/// Channel flags +static const uint32_t MESHLINK_CHANNEL_RELIABLE = 1; // Data is retransmitted when packets are lost. +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_TCP = 3; // Select TCP semantics. +static const uint32_t MESHLINK_CHANNEL_UDP = 0; // Select UDP semantics. /// A variable holding the last encountered error from MeshLink. /** This is a thread local variable that contains the error code of the most recent error * encountered by a MeshLink API function called in the current thread. * The variable is only updated when an error is encountered, and is not reset to MESHLINK_OK - * if a function returned succesfully. + * if a function returned successfully. */ extern __thread meshlink_errno_t meshlink_errno; #ifndef MESHLINK_INTERNAL_H struct meshlink_handle { - const char *name; - void *priv; + const char *const name; ///< Textual name of ourself. It is stored in a nul-terminated C string, which is allocated by MeshLink. + void *priv; ///< Private pointer which may be set freely by the application, and is never used or modified by MeshLink. }; struct meshlink_node { - const char *name; ///< Textual name of this node. It is stored in a nul-terminated C string, which is allocated by MeshLink. - void *priv; ///< Private pointer which may be set freely by the application, and is never used or modified by MeshLink. + const char *const name; ///< Textual name of this node. It is stored in a nul-terminated C string, which is allocated by MeshLink. + void *priv; ///< Private pointer which may be set freely by the application, and is never used or modified by MeshLink. +}; + +struct meshlink_submesh { + const char *const name; ///< Textual name of this Sub-Mesh. It is stored in a nul-terminated C string, which is allocated by MeshLink. + void *priv; ///< Private pointer which may be set freely by the application, and is never used or modified by MeshLink. }; struct meshlink_channel { + struct meshlink_node *const node; ///< Pointer to the peer of this channel. + void *priv; ///< Private pointer which may be set freely by the application, and is never used or modified by MeshLink. }; #endif // MESHLINK_INTERNAL_H @@ -108,9 +140,54 @@ struct meshlink_channel { */ extern const char *meshlink_strerror(meshlink_errno_t err); +/// Create a new meshlink_open_params_t struct. +/** This function allocates and initializes a new meshlink_open_params_t struct that can be passed to meshlink_open_ex(). + * The resulting struct may be reused for multiple calls to meshlink_open_ex(). + * After the last use, the application must free this struct using meshlink_open_params_free(). + * + * @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. + * @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. + * @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. + * @param devclass The device class which will be used in the mesh. + * + * @return A pointer to a meshlink_open_params_t which can be passed to meshlink_open_ex(), or NULL in case of an error. + * The pointer is valid until meshlink_open_params_free() is called. + */ +extern meshlink_open_params_t *meshlink_open_params_init(const char *confbase, const char *name, const char *appname, dev_class_t devclass); + +/// Free a meshlink_open_params_t struct. +/** This function frees a meshlink_open_params_t struct and all resources associated with it. + * + * @param params A pointer to a meshlink_open_params_t which must have been created earlier with meshlink_open_params_init(). + */ +extern void meshlink_open_params_free(meshlink_open_params_t *params); + /// Open or create a MeshLink instance. /** This function opens or creates a MeshLink instance. - * The state is stored in the configuration directory passed in the variable @a confbase @a. + * All parameters needed by MeshLink are passed via a meshlink_open_params_t struct, + * which must have been initialized earlier by the application. + * + * 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 params A pointer to a meshlink_open_params_t which must be filled in by the application. + * After the function returns, the application is free to reuse or free @a params. + * + * @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_ex(const meshlink_open_params_t *params); + +/// Open or create a MeshLink instance. +/** This function opens or creates a MeshLink instance. + * The state is stored in the configuration directory passed in the variable @a confbase. * 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. @@ -125,20 +202,32 @@ extern const char *meshlink_strerror(meshlink_errno_t err); * 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. + * After the function returns, the application is free to overwrite or free @a confbase. * @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. + * After the function returns, the application is free to overwrite or free @a name. * @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 dclass The device class which will be used in the mesh. + * After the function returns, the application is free to overwrite or free @a name. + * @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(const char *confbase, const char *name, const char* appname, dclass_t dclass); +extern meshlink_handle_t *meshlink_open(const char *confbase, const char *name, const char *appname, dev_class_t devclass); -/// is used by the C++ wrapper to allocate more memory behind the handle -extern meshlink_handle_t *meshlink_open_with_size(const char *confbase, const char *name, const char* appname, dclass_t dclass, size_t size); +/// 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. + * + * It is allowed to call this function even if MeshLink is already started, in which case it will return true. + * + * @param mesh A handle which represents an instance of MeshLink. + * + * @param submesh Name of the new Sub-Mesh to create. + * + * @return A pointer to a meshlink_submesh_t which represents this instance of SubMesh, or NULL in case of an error. + * The pointer is valid until meshlink_close() is called. + */ +meshlink_submesh_t *meshlink_submesh_open(meshlink_handle_t *mesh, const char *submesh); /// Start MeshLink. /** This function causes MeshLink to open network sockets, make outgoing connections, and @@ -148,7 +237,7 @@ extern meshlink_handle_t *meshlink_open_with_size(const char *confbase, const ch * * @param mesh A handle which represents an instance of MeshLink. * - * @return This function will return true if MeshLink has succesfully started, false otherwise. + * @return This function will return true if MeshLink has successfully started, false otherwise. */ extern bool meshlink_start(meshlink_handle_t *mesh); @@ -157,6 +246,7 @@ extern bool meshlink_start(meshlink_handle_t *mesh); * close all sockets, and shut down its own thread. * * This function always succeeds. It is allowed to call meshlink_stop() even if MeshLink is already stopped or has never been started. + * Channels that are still open will remain valid, but any communication via channels will stop as well. * * @param mesh A handle which represents an instance of MeshLink. */ @@ -164,7 +254,7 @@ extern void meshlink_stop(meshlink_handle_t *mesh); /// Close the MeshLink handle. /** This function calls meshlink_stop() if necessary, - * and frees the struct meshlink_handle and all associacted memory allocated by MeshLink. + * and frees the struct meshlink_handle and all associacted memory allocated by MeshLink, including all channels. * Afterwards, the handle and any pointers to a struct meshlink_node or struct meshlink_channel are invalid. * * It is allowed to call this function at any time on a valid handle, except inside callback functions. @@ -175,6 +265,18 @@ extern void meshlink_stop(meshlink_handle_t *mesh); */ extern void meshlink_close(meshlink_handle_t *mesh); +/// Destroy a MeshLink instance. +/** This function remove all configuration files of a MeshLink instance. It should only be called when the application + * does not have an open handle to this instance. Afterwards, a call to meshlink_open() will create a completely + * new instance. + * + * @param confbase The directory in which MeshLink stores its configuration files. + * After the function returns, the application is free to overwrite or free @a confbase. + * + * @return This function will return true if the MeshLink instance was successfully destroyed, false otherwise. + */ +extern bool meshlink_destroy(const char *confbase); + /// A callback for receiving data from the mesh. /** @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. @@ -219,13 +321,33 @@ typedef void (*meshlink_node_status_cb_t)(meshlink_handle_t *mesh, meshlink_node */ extern void meshlink_set_node_status_cb(meshlink_handle_t *mesh, meshlink_node_status_cb_t cb); +/// A callback reporting duplicate node detection. +/** @param mesh A handle which represents an instance of MeshLink. + * @param node A pointer to a meshlink_node_t describing the node which is duplicate. + * This pointer is valid until meshlink_close() is called. + */ +typedef void (*meshlink_node_duplicate_cb_t)(meshlink_handle_t *mesh, meshlink_node_t *node); + +/// Set the node duplicate callback. +/** This functions sets the callback that is called whenever a duplicate node is detected. + * 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 a duplicate node is detected. + * If a NULL pointer is given, the callback will be disabled. + */ +extern void meshlink_set_node_duplicate_cb(meshlink_handle_t *mesh, meshlink_node_duplicate_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_CRITICAL ///< Critical errors which cause MeshLink to fail completely. } meshlink_log_level_t; /// A callback for receiving log messages generated by MeshLink. @@ -241,16 +363,16 @@ typedef void (*meshlink_log_cb_t)(meshlink_handle_t *mesh, meshlink_log_level_t /// Set the log callback. /** This functions sets the callback that is called whenever MeshLink has some information to log. * - * The @a mesh @a parameter can either be a valid MeshLink handle, or NULL. + * The @a mesh parameter can either be a valid MeshLink handle, or NULL. * In case it is NULL, the callback will be called for errors that happen outside the context of a valid mesh instance. * Otherwise, it will be called for errors that happen in the context of the given mesh instance. * - * If @a mesh @a is not NULL, then the callback is run in MeshLink's own thread. + * If @a mesh is not NULL, then the callback is run in MeshLink's own thread. * It is 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. * - * The @a mesh @a parameter can either be a valid MeshLink handle, or NULL. + * The @a mesh parameter can either be a valid MeshLink handle, or NULL. * In case it is NULL, the callback will be called for errors that happen outside the context of a valid mesh instance. * Otherwise, it will be called for errors that happen in the context of the given mesh instance. * @@ -274,7 +396,7 @@ extern void meshlink_set_log_cb(meshlink_handle_t *mesh, meshlink_log_level_t le * @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. * After meshlink_send() returns, the application is free to overwrite or free this buffer. - * It is valid to specify a NULL pointer, but only if @a len @a is also 0. + * It is valid to specify a NULL pointer, but only if @a len is also 0. * @param len The length of the data. * @return This function will return true if MeshLink has queued the message for transmission, and false otherwise. * A return value of true does not guarantee that the message will actually arrive at the destination. @@ -296,12 +418,22 @@ extern bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, */ extern ssize_t meshlink_get_pmtu(meshlink_handle_t *mesh, meshlink_node_t *destination); +/// Get a handle for our own node. +/** This function returns a handle for the local node. + * + * @param mesh A handle which represents an instance of MeshLink. + * + * @return A pointer to a meshlink_node_t which represents the local node. + * The pointer is guaranteed to be valid until meshlink_close() is called. + */ +extern meshlink_node_t *meshlink_get_self(meshlink_handle_t *mesh); + /// Get a handle for a specific node. /** This function returns a handle for the node with the given name. * * @param mesh A handle which represents an instance of MeshLink. * @param name The name of the node for which a handle is requested. - * After this function returns, the application is free to overwrite or free @a name @a. + * After this function returns, the application is free to overwrite or free @a name. * * @return A pointer to a meshlink_node_t which represents the requested node, * or NULL if the requested node does not exist. @@ -316,7 +448,7 @@ extern meshlink_node_t *meshlink_get_node(meshlink_handle_t *mesh, const char *n * @param mesh A handle which represents an instance of MeshLink. * @param node A pointer to a meshlink_node_t describing the node. * - * @return A nul-terminated C string containing the fingerprint of the node's public key in a printable ASCII format. + * @return A nul-terminated C string containing the fingerprint of the node's public key in a printable ASCII format. * The application should call free() after it is done using this string. */ extern char *meshlink_get_fingerprint(meshlink_handle_t *mesh, meshlink_node_t *node); @@ -330,12 +462,12 @@ extern char *meshlink_get_fingerprint(meshlink_handle_t *mesh, meshlink_node_t * * The application is allowed to call free() on the array whenever it wishes. * The pointers in the array are valid until meshlink_close() is called. * @param nmemb A pointer to a variable holding the number of nodes that are stored in the array. - * In case the @a nodes @a argument is not NULL, MeshLink might call realloc() on the array to change its size. + * In case the @a nodes argument is not NULL, MeshLink might call realloc() on the array to change its size. * The contents of this variable will be changed to reflect the new size of the array. * * @return A pointer to an array containing pointers to all known nodes, or NULL in case of an error. - * If the @a nodes @a argument was not NULL, then the return value can either be the same value or a different value. - * If it is a new value, the old value of @a nodes @a should not be used anymore. + * If the @a nodes argument was not NULL, then the return value can either be the same value or a different value. + * If it is a new value, the old value of @a nodes should not be used anymore. * If the new value is NULL, then the old array will have been freed by MeshLink. */ extern meshlink_node_t **meshlink_get_all_nodes(meshlink_handle_t *mesh, meshlink_node_t **nodes, size_t *nmemb); @@ -356,6 +488,66 @@ extern meshlink_node_t **meshlink_get_all_nodes(meshlink_handle_t *mesh, meshlin */ extern bool meshlink_sign(meshlink_handle_t *mesh, const void *data, size_t len, void *signature, size_t *siglen); +/// Get the list of all nodes by device class. +/** This function returns a list with handles for all the nodes that matches with the given @a devclass. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param devclass Device class of the nodes for which the list has to be obtained. + * @param nodes A pointer to a previously allocated array of pointers to meshlink_node_t, or NULL in which case MeshLink will allocate a new array. + * The application can supply an array it allocated itself with malloc, or the return value from the previous call to this function (which is the preferred way). + * The application is allowed to call free() on the array whenever it wishes. + * The pointers in the array are valid until meshlink_close() is called. + * @param nmemb A pointer to a variable holding the number of nodes with the same @a device class that are stored in the array. + * In case the @a nodes argument is not NULL, MeshLink might call realloc() on the array to change its size. + * The contents of this variable will be changed to reflect the new size of the array. + * + * @return A pointer to an array containing pointers to all known nodes of the given device class, or NULL in case of an error. + * If the @a nodes argument was not NULL, then the return value can either be the same value or a different value. + * If it is a new value, the old value of @a nodes should not be used anymore. + * If the new value is NULL, then the old array will have been freed by MeshLink. + */ +extern meshlink_node_t **meshlink_get_all_nodes_by_dev_class(meshlink_handle_t *mesh, dev_class_t devclass, meshlink_node_t **nodes, size_t *nmemb); + +/// Get the list of all nodes by Submesh. +/** This function returns a list with handles for all the nodes that matches with the given @a Submesh. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param submesh Submesh handle of the nodes for which the list has to be obtained. + * @param nodes A pointer to a previously allocated array of pointers to meshlink_node_t, or NULL in which case MeshLink will allocate a new array. + * The application can supply an array it allocated itself with malloc, or the return value from the previous call to this function (which is the preferred way). + * The application is allowed to call free() on the array whenever it wishes. + * The pointers in the array are valid until meshlink_close() is called. + * @param nmemb A pointer to a variable holding the number of nodes with the same @a device class that are stored in the array. + * In case the @a nodes argument is not NULL, MeshLink might call realloc() on the array to change its size. + * The contents of this variable will be changed to reflect the new size of the array. + * + * @return A pointer to an array containing pointers to all known nodes of the given Submesh, or NULL in case of an error. + * If the @a nodes argument was not NULL, then the return value can either be the same value or a different value. + * If it is a new value, the old value of @a nodes should not be used anymore. + * If the new value is NULL, then the old array will have been freed by MeshLink. + */ +extern meshlink_node_t **meshlink_get_all_nodes_by_submesh(meshlink_handle_t *mesh, meshlink_submesh_t *submesh, meshlink_node_t **nodes, size_t *nmemb); + +/// Get the node's device class. +/** This function returns the device class of the given node. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param node A pointer to a meshlink_node_t describing the node. + * + * @return This function returns the device class of the @a node, or -1 in case of an error. + */ +extern dev_class_t meshlink_get_node_dev_class(meshlink_handle_t *mesh, meshlink_node_t *node); + +/// Get the node's submesh handle. +/** This function returns the submesh handle of the given node. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param node A pointer to a meshlink_node_t describing the node. + * + * @return This function returns the submesh handle of the @a node, or NULL in case of an error. + */ +extern meshlink_submesh_t *meshlink_get_node_submesh(meshlink_handle_t *mesh, meshlink_node_t *node); + /// 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. * @@ -371,6 +563,25 @@ extern bool meshlink_sign(meshlink_handle_t *mesh, const void *data, size_t len, */ extern bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const void *data, size_t len, const void *signature, size_t siglen); +/// Set the canonical Address for a node. +/** This function sets the canonical Address for a node. + * This address is stored permanently until it is changed by another call to this function, + * unlike other addresses associated with a node, + * such as those added with meshlink_hint_address() or addresses discovered at runtime. + * + * If a canonical Address is set for the local node, + * it will be used for the hostname part of generated invitation URLs. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param node A pointer to a meshlink_node_t describing the node. + * @param address A nul-terminated C string containing the address, which can be either in numeric format or a hostname. + * @param port A nul-terminated C string containing the port, which can be either in numeric or symbolic format. + * If it is NULL, the listening port's number will be used. + * + * @return This function returns true if the address was added, false otherwise. + */ +extern bool meshlink_set_canonical_address(meshlink_handle_t *mesh, meshlink_node_t *node, const char *address, const char *port); + /// Add an Address for the local node. /** This function adds an Address for the local node, which will be used for invitation URLs. * @@ -381,29 +592,175 @@ extern bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, co */ extern bool meshlink_add_address(meshlink_handle_t *mesh, const char *address); +/// Try to discover the external address for the local node. +/** This function performs tries to discover the local node's external address + * by contacting the meshlink.io server. If a reverse lookup of the address works, + * the FQDN associated with the address will be returned. + * + * Please note that this is function only returns a single address, + * even if the local node might have more than one external address. + * In that case, there is no control over which address will be selected. + * Also note that if you have a dynamic IP address, or are behind carrier-grade NAT, + * there is no guarantee that the external address will be valid for an extended period of time. + * + * This function is blocking. It can take several seconds before it returns. + * There is no guarantee it will be able to resolve the external address. + * Failures might be because by temporary network outages. + * + * @param mesh A handle which represents an instance of MeshLink. + * + * @return This function returns a pointer to a C string containing the discovered external address, + * or NULL if there was an error looking up the address. + * After meshlink_get_external_address() returns, the application is free to overwrite or free this string. + */ +extern char *meshlink_get_external_address(meshlink_handle_t *mesh); + +/// Try to discover the external address for the local node. +/** This function performs tries to discover the local node's external address + * by contacting the meshlink.io server. If a reverse lookup of the address works, + * the FQDN associated with the address will be returned. + * + * Please note that this is function only returns a single address, + * even if the local node might have more than one external address. + * In that case, there is no control over which address will be selected. + * Also note that if you have a dynamic IP address, or are behind carrier-grade NAT, + * there is no guarantee that the external address will be valid for an extended period of time. + * + * This function is blocking. It can take several seconds before it returns. + * There is no guarantee it will be able to resolve the external address. + * Failures might be because by temporary network outages. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param address_family The address family to check, for example AF_INET or AF_INET6. If AF_UNSPEC is given, + * this might return the external address for any working address family. + * + * @return This function returns a pointer to a C string containing the discovered external address, + * or NULL if there was an error looking up the address. + * After meshlink_get_external_address_for_family() returns, the application is free to overwrite or free this string. + */ +extern char *meshlink_get_external_address_for_family(meshlink_handle_t *mesh, int address_family); + +/// Try to discover the local address for the local node. +/** This function performs tries to discover the address of the local interface used for outgoing connection. + * + * Please note that this is function only returns a single address, + * even if the interface might have more than one address. + * In that case, there is no control over which address will be selected. + * Also note that if you have a dynamic IP address, + * there is no guarantee that the local address will be valid for an extended period of time. + * + * This function will fail if it couldn't find a local address for the given address family. + * If hostname resolving is requested, this function may block for a few seconds. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param address_family The address family to check, for example AF_INET or AF_INET6. If AF_UNSPEC is given, + * this might return the local address for any working address family. + * + * @return This function returns a pointer to a C string containing the discovered local address, + * or NULL if there was an error looking up the address. + * After meshlink_get_local_address_for_family() returns, the application is free to overwrite or free this string. + */ +extern char *meshlink_get_local_address_for_family(meshlink_handle_t *mesh, int address_family); + +/// Try to discover the external address for the local node, and add it to its list of addresses. +/** This function is equivalent to: + * + * meshlink_add_address(mesh, meshlink_get_external_address(mesh)); + * + * Read the description of meshlink_get_external_address() for the limitations of this function. + * + * @param mesh A handle which represents an instance of MeshLink. + * + * @return This function returns true if the address was added, false otherwise. + */ +extern bool meshlink_add_external_address(meshlink_handle_t *mesh); + +/// Get the network port used by the local node. +/** This function returns the network port that the local node is listening on. + * + * @param mesh A handle which represents an instance of MeshLink. + * + * @return This function returns the port number, or -1 in case of an error. + */ +extern int meshlink_get_port(meshlink_handle_t *mesh); + +/// Set the network port used by the local node. +/** This function sets the network port that the local node is listening on. + * It may only be called when the mesh is not running. + * If unsure, call meshlink_stop() before calling this function. + * Also note that if your node is already part of a mesh with other nodes, + * that the other nodes may no longer be able to initiate connections to the local node, + * since they will try to connect to the previously configured port. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param port The port number to listen on. This must be between 0 and 65535. + * 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. + */ + +extern bool meshlink_set_port(meshlink_handle_t *mesh, int port); + +/// Set the timeout for invitations. +/** This function sets the timeout for invitations. + * Note that timeouts are only checked at the time a node tries to join using an invitation. + * The default timeout for invitations is 1 week. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param timeout The timeout for invitations in seconds. + */ +extern void meshlink_set_invitation_timeout(meshlink_handle_t *mesh, int timeout); + +/// 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. + * The generated invitation is a string containing a URL. + * 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 mesh A handle which represents an instance of MeshLink. + * @param submesh A handle which represents an instance of SubMesh. + * @param name A nul-terminated C string containing the name that the invitee will be allowed to use in the mesh. + * After this function returns, the application is free to overwrite or free @a name. + * @param flags A bitwise-or'd combination of flags that controls how the URL is generated. + * + * @return This function returns a nul-terminated C string that contains the invitation URL, or NULL in case of an error. + * The application should call free() after it has finished using the URL. + */ +extern char *meshlink_invite_ex(meshlink_handle_t *mesh, meshlink_submesh_t *submesh, const char *name, uint32_t flags); + /// 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. * The generated invitation is a string containing a URL. * 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. * + * Calling this function is equal to callen meshlink_invite_ex() with flags set to 0. + * * @param mesh A handle which represents an instance of MeshLink. + * @param submesh A handle which represents an instance of SubMesh. * @param name A nul-terminated C string containing the name that the invitee will be allowed to use in the mesh. - * After this function returns, the application is free to overwrite or free @a name @a. + * After this function returns, the application is free to overwrite or free @a name. * * @return This function returns a nul-terminated C string that contains the invitation URL, or NULL in case of an error. * The application should call free() after it has finished using the URL. */ -extern char *meshlink_invite(meshlink_handle_t *mesh, const char *name); +extern char *meshlink_invite(meshlink_handle_t *mesh, meshlink_submesh_t *submesh, const char *name); /// Use an invitation to join a mesh. /** This function allows the local node to join an existing mesh using an invitation URL generated by another node. * 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. + * After a successfully accepted invitation, the name of the local node may have changed. + * + * This function may only be called on a mesh that has not been started yet and which is not already part of an existing mesh. + * + * This function is blocking. It can take several seconds before it returns. + * There is no guarantee it will perform a successful join. + * Failures might be caused by temporary network outages, or by the invitation having expired. * * @param mesh A handle which represents an instance of MeshLink. * @param invitation A nul-terminated C string containing the invitation URL. - * After this function returns, the application is free to overwrite or free @a invitation @a. + * After this function returns, the application is free to overwrite or free @a invitation. * * @return This function returns true if the local node joined the mesh it was invited to, false otherwise. */ @@ -433,7 +790,7 @@ extern char *meshlink_export(meshlink_handle_t *mesh); * * @param mesh A handle which represents an instance of MeshLink. * @param data A nul-terminated C string containing the other node's exported key and addresses. - * After this function returns, the application is free to overwrite or free @a data @a. + * After this function returns, the application is free to overwrite or free @a data. * * @return This function returns true if the data was valid and the other node has been granted access to the mesh, false otherwise. */ @@ -455,9 +812,21 @@ extern void meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node); * and will send data to it and accept any data received from it. * * @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. + * @param node A pointer to a meshlink_node_t describing the node to be whitelisted. */ -extern void meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node); +extern void meshlink_whitelist(meshlink_handle_t *mesh, meshlink_node_t *node); + +/// Set whether new nodes are blacklisted by default. +/** This function sets the blacklist behaviour for newly discovered nodes. + * If set to true, new nodes will be automatically blacklisted. + * If set to false, which is the default, new nodes are automatically whitelisted. + * The whitelist/blacklist status of a node may be changed afterwards with the + * meshlink_whitelist() and meshlink_blacklist() functions. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param blacklist True if new nodes are to be blacklisted, false if whitelisted. + */ +extern void meshlink_set_default_blacklist(meshlink_handle_t *mesh, bool blacklist); /// A callback for accepting incoming channels. /** This function is called whenever a remote node wants to open a channel to the local node. @@ -474,8 +843,6 @@ extern void meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node); * If the application rejects the incoming channel by returning false, * then this handle is invalid after the callback returns * (the callback does not need to call meshlink_channel_close() itself in this case). - * @param node The node from which this channel is being initiated. - * The pointer is guaranteed to be valid until meshlink_close() is called. * @param port The port number the peer wishes to connect to. * @param data A pointer to a buffer containing data already received, or NULL in case no data has been received yet. (Not yet used.) * The pointer is only valid during the lifetime of the callback. @@ -485,14 +852,14 @@ extern void meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node); * @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); +typedef bool (*meshlink_channel_accept_cb_t)(meshlink_handle_t *mesh, meshlink_channel_t *channel, uint16_t port, const void *data, size_t len); /// A callback for receiving data from a channel. /** This function is called whenever data is received from a remote node on a channel. * * This function is also called in case the channel has been closed by the remote node, or when the channel is terminated abnormally. - * In both cases, @a data @a will be NULL and @a len @a will be 0, and meshlink_errno will be set. - * In any case, the @a channel @a handle will still be valid until the application calls meshlink_close(). + * In both cases, @a data will be NULL and @a len will be 0, and meshlink_errno will be set. + * In any case, the @a channel handle will still be valid until the application calls meshlink_close(). * * @param mesh A handle which represents an instance of MeshLink. * @param channel A handle for the channel. @@ -503,6 +870,16 @@ typedef bool (*meshlink_channel_accept_cb_t)(meshlink_handle_t *mesh, meshlink_c */ typedef void (*meshlink_channel_receive_cb_t)(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len); +/// A callback informing the application when data can be sent on a channel. +/** This function is called whenever there is enough free buffer space so a call to meshlink_channel_send() will succeed. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel. + * @param len The maximum amount of data that is guaranteed to be accepted by meshlink_channel_send(), + * or 0 in case of an error. + */ +typedef void (*meshlink_channel_poll_cb_t)(meshlink_handle_t *mesh, meshlink_channel_t *channel, 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. @@ -532,6 +909,43 @@ extern void meshlink_set_channel_accept_cb(meshlink_handle_t *mesh, meshlink_cha */ extern void meshlink_set_channel_receive_cb(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_channel_receive_cb_t cb); +/// Set the poll callback. +/** This functions sets the callback that is called whenever data can be sent 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 pass data to or from 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 data can be sent to another node. + * If a NULL pointer is given, the callback will be disabled. + */ +extern void meshlink_set_channel_poll_cb(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_channel_poll_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. + * + * This function returns a pointer to a struct meshlink_channel that will be allocated by MeshLink. + * When the application does no longer need to use this channel, it must call meshlink_close() + * to free its resources. + * + * @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. + * The pointer may be NULL, in which case incoming data is ignored. + * @param data A pointer to a buffer containing data to already queue for sending, or NULL if there is no data to send. + * After meshlink_send() returns, the application is free to overwrite or free this buffer. + * @param len The length of the data, or 0 if there is no data to send. + * @param flags A bitwise-or'd combination of flags that set the semantics for this channel. + * + * @return A handle for the channel, or NULL in case of an error. + * The handle is valid until meshlink_channel_close() is called. + */ +extern meshlink_channel_t *meshlink_channel_open_ex(meshlink_handle_t *mesh, meshlink_node_t *node, uint16_t port, meshlink_channel_receive_cb_t cb, const void *data, size_t len, uint32_t flags); + /// 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. @@ -540,6 +954,9 @@ extern void meshlink_set_channel_receive_cb(meshlink_handle_t *mesh, meshlink_ch * When the application does no longer need to use this channel, it must call meshlink_close() * to free its resources. * + * Calling this function is equivalent to calling meshlink_channel_open_ex() + * with the flags set to MESHLINK_CHANNEL_TCP. + * * @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. @@ -594,22 +1011,62 @@ extern void meshlink_channel_close(meshlink_handle_t *mesh, meshlink_channel_t * */ extern ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len); +/// Get channel flags. +/** This returns the flags used when opening this channel. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param channel A handle for the channel. + * + * @return The flags set for this channel. + */ +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. * - * @param mesh A handle which represents an instance of MeshLink. - * @param hostname The hostname which can be found at the given address. - * The caller is free to overwrite or free this string - * once meshlink returns. - * @param addr The IP address and port which should be tried for the - * given hostname. The caller is free to overwrite or free - * this memory once meshlink returns. + * @param mesh A handle which represents an instance of MeshLink. + * @param node A pointer to a meshlink_node_t describing the node to add the address hint for. + * @param addr The IP address and port which should be tried for the + * given hostname. The caller is free to overwrite or free + * this memory once meshlink returns. */ extern void meshlink_hint_address(meshlink_handle_t *mesh, meshlink_node_t *node, const struct sockaddr *addr); +/// Enable or disable zeroconf discovery of local peers + +/** This controls whether zeroconf discovery using the Catta library will be + * enabled to search for peers on the local network. By default, it is enabled. + * + * @param mesh A handle which represents an instance of MeshLink. + * @param enable Set to true to enable discovery, false to disable. + */ +extern void meshlink_enable_discovery(meshlink_handle_t *mesh, bool enable); + #ifdef __cplusplus } #endif -#endif // MESHLINK_H +#endif