diff --git a/libknet/libknet.h b/libknet/libknet.h index 68ac16c9..27399e84 100644 --- a/libknet/libknet.h +++ b/libknet/libknet.h @@ -1,1942 +1,1942 @@ /* * Copyright (C) 2010-2018 Red Hat, Inc. All rights reserved. * * Authors: Fabio M. Di Nitto * Federico Simoncelli * * This software licensed under GPL-2.0+, LGPL-2.0+ */ #ifndef __LIBKNET_H__ #define __LIBKNET_H__ #include #include #include #include /** * @file libknet.h * @brief kronosnet API include file * @copyright Copyright (C) 2010-2018 Red Hat, Inc. All rights reserved. * * Kronosnet is an advanced VPN system for High Availability applications. */ /* * libknet limits */ /* * Maximum number of hosts */ typedef uint16_t knet_node_id_t; #define KNET_MAX_HOST 65536 /* * Maximum number of links between 2 hosts */ #define KNET_MAX_LINK 8 /* * Maximum packet size that should be written to datafd * see knet_handle_new for details */ #define KNET_MAX_PACKET_SIZE 65536 /* * Buffers used for pretty logging * host is used to store both ip addresses and hostnames */ #define KNET_MAX_HOST_LEN 256 #define KNET_MAX_PORT_LEN 6 /* * Some notifications can be generated either on TX or RX */ #define KNET_NOTIFY_TX 0 #define KNET_NOTIFY_RX 1 /* * Link flags */ /* * Where possible, set traffic priority to high. * On Linux this sets the TOS to INTERACTIVE (6), * see tc-prio(8) for more infomation */ #define KNET_LINK_FLAG_TRAFFICHIPRIO (1ULL << 0) typedef struct knet_handle *knet_handle_t; /* * Handle structs/API calls */ /** * knet_handle_new * * @brief create a new instance of a knet handle * * host_id - Each host in a knet is identified with a unique * ID. when creating a new handle local host_id * must be specified (0 to UINT16T_MAX are all valid). * It is the user's responsibility to check that the value * is unique, or bad things might happen. * * log_fd - Write file descriptor. If set to a value > 0, it will be used * to write log packets from libknet to the application. * Setting to 0 will disable logging from libknet. * It is possible to enable logging at any given time (see logging API). * Make sure to either read from this filedescriptor properly and/or * mark it O_NONBLOCK, otherwise if the fd becomes full, libknet could * block. * * default_log_level - * If logfd is specified, it will initialize all subsystems to log * at default_log_level value. (see logging API) * * @return * on success, a new knet_handle_t is returned. * on failure, NULL is returned and errno is set. * knet-specific errno values: * ENAMETOOLONG - socket buffers couldn't be set big enough * ERANGE - buffer size readback returned unexpected type */ knet_handle_t knet_handle_new(knet_node_id_t host_id, int log_fd, uint8_t default_log_level); /** * knet_handle_free * @brief Destroy a knet handle, free all resources * * knet_h - pointer to knet_handle_t * * @return * knet_handle_free returns * 0 on success * -1 on error and errno is set. */ int knet_handle_free(knet_handle_t knet_h); /** * knet_handle_enable_sock_notify * @brief Register a callback to receive socket events * * knet_h - pointer to knet_handle_t * * sock_notify_fn_private_data * void pointer to data that can be used to identify * the callback. * * sock_notify_fn * A callback function that is invoked every time * a socket in the datafd pool will report an error (-1) * or an end of read (0) (see socket.7). * This function MUST NEVER block or add substantial delays. * The callback is invoked in an internal unlocked area * to allow calls to knet_handle_add_datafd/knet_handle_remove_datafd * to swap/replace the bad fd. * if both err and errno are 0, it means that the socket * has received a 0 byte packet (EOF?). * The callback function must either remove the fd from knet * (by calling knet_handle_remove_fd()) or dup a new fd in its place. * Failure to do this can cause problems. * * @return * knet_handle_enable_sock_notify returns * 0 on success * -1 on error and errno is set. */ int knet_handle_enable_sock_notify(knet_handle_t knet_h, void *sock_notify_fn_private_data, void (*sock_notify_fn) ( void *private_data, int datafd, int8_t channel, uint8_t tx_rx, int error, int errorno)); /* sorry! can't call it errno ;) */ #define KNET_DATAFD_MAX 32 /** * knet_handle_add_datafd * * @brief Install a file descriptor for communication * * IMPORTANT: In order to add datafd to knet, knet_handle_enable_sock_notify * _MUST_ be set and be able to handle both errors (-1) and * 0 bytes read / write from the provided datafd. * On read error (< 0) from datafd, the socket is automatically * removed from polling to avoid spinning on dead sockets. * It is safe to call knet_handle_remove_datafd even on sockets * that have been removed. * * knet_h - pointer to knet_handle_t * * *datafd - read/write file descriptor. * knet will read data here to send to the other hosts * and will write data received from the network. * Each data packet can be of max size KNET_MAX_PACKET_SIZE! * Applications using knet_send/knet_recv will receive a * proper error if the packet size is not within boundaries. * Applications using their own functions to write to the * datafd should NOT write more than KNET_MAX_PACKET_SIZE. * * Please refer to handle.c on how to set up a socketpair. * * datafd can be 0, and knet_handle_add_datafd will create a properly * populated socket pair the same way as ping_test, or a value * higher than 0. A negative number will return an error. * On exit knet_handle_free will take care to cleanup the * socketpair only if they have been created by knet_handle_add_datafd. * * It is possible to pass either sockets or normal fds. * User provided datafd will be marked as non-blocking and close-on-exit. * * *channel - This value has the same effect of VLAN tagging. * A negative value will auto-allocate a channel. * Setting a value between 0 and 31 will try to allocate that * specific channel (unless already in use). * * It is possible to add up to 32 datafds but be aware that each * one of them must have a receiving end on the other host. * * Example: * hostA channel 0 will be delivered to datafd on hostB channel 0 * hostA channel 1 to hostB channel 1. * * Each channel must have a unique file descriptor. * * If your application could have 2 channels on one host and one * channel on another host, then you can use dst_host_filter * to manipulate channel values on TX and RX. * * @return * knet_handle_add_datafd returns * @retval 0 on success, * *datafd will be populated with a socket if the original value was 0 * or if a specific fd was set, the value is untouched. * *channel will be populated with a channel number if the original value * was negative or the value is untouched if a specific channel * was requested. * * @retval -1 on error and errno is set. * *datafd and *channel are untouched or empty. */ int knet_handle_add_datafd(knet_handle_t knet_h, int *datafd, int8_t *channel); /** * knet_handle_remove_datafd * @brief Remove a file descriptor from knet * * knet_h - pointer to knet_handle_t * * datafd - file descriptor to remove. * NOTE that if the socket/fd was created by knet_handle_add_datafd, * the socket will be closed by libknet. * * @return * knet_handle_remove_datafd returns * 0 on success * -1 on error and errno is set. */ int knet_handle_remove_datafd(knet_handle_t knet_h, int datafd); /** * knet_handle_get_channel * @brief Get the channel associated with a file descriptor * * knet_h - pointer to knet_handle_t * * datafd - get the channel associated to this datafd * * *channel - will contain the result * * @return * knet_handle_get_channel returns * @retval 0 on success * and *channel will contain the result * @retval -1 on error and errno is set. * and *channel content is meaningless */ int knet_handle_get_channel(knet_handle_t knet_h, const int datafd, int8_t *channel); /** * knet_handle_get_datafd * @brief Get the file descriptor associated with a channel * * knet_h - pointer to knet_handle_t * * channel - get the datafd associated to this channel * * *datafd - will contain the result * * @return * knet_handle_get_datafd returns * @retval 0 on success * and *datafd will contain the results * @retval -1 on error and errno is set. * and *datafd content is meaningless */ int knet_handle_get_datafd(knet_handle_t knet_h, const int8_t channel, int *datafd); /** * knet_recv * @brief Receive data from knet nodes * * knet_h - pointer to knet_handle_t * * buff - pointer to buffer to store the received data * * buff_len - buffer length * * channel - channel number * * @return * knet_recv is a commodity function to wrap iovec operations * around a socket. It returns a call to readv(2). */ ssize_t knet_recv(knet_handle_t knet_h, char *buff, const size_t buff_len, const int8_t channel); /** * knet_send * @brief Send data to knet nodes * * knet_h - pointer to knet_handle_t * * buff - pointer to the buffer of data to send * * buff_len - length of data to send * * channel - channel number * * @return * knet_send is a commodity function to wrap iovec operations * around a socket. It returns a call to writev(2). */ ssize_t knet_send(knet_handle_t knet_h, const char *buff, const size_t buff_len, const int8_t channel); /** * knet_send_sync * * @brief Synchronously send data to knet nodes * * knet_h - pointer to knet_handle_t * * buff - pointer to the buffer of data to send * * buff_len - length of data to send * * channel - data channel to use (see knet_handle_add_datafd(3)) * * All knet RX/TX operations are async for performance reasons. * There are applications that might need a sync version of data * transmission and receive errors in case of failure to deliver * to another host. * knet_send_sync bypasses the whole TX async layer and delivers * data directly to the link layer, and returns errors accordingly. * knet_send_sync sends only one packet to one host at a time. * It does NOT support multiple destinations or multicast packets. * Decision is still based on dst_host_filter_fn. * * @return * knet_send_sync returns 0 on success and -1 on error. * In addition to normal sendmmsg errors, knet_send_sync can fail * due to: * * @retval ECANCELED - data forward is disabled * @retval EFAULT - dst_host_filter fatal error * @retval EINVAL - dst_host_filter did not provide dst_host_ids_entries on unicast pckts * @retval E2BIG - dst_host_filter did return more than one dst_host_ids_entries on unicast pckts * @retval ENOMSG - received unknown message type * @retval EHOSTDOWN - unicast pckt cannot be delivered because dest host is not connected yet * @retval ECHILD - crypto failed * @retval EAGAIN - sendmmsg was unable to send all messages and there was no progress during retry */ int knet_send_sync(knet_handle_t knet_h, const char *buff, const size_t buff_len, const int8_t channel); /** * knet_handle_enable_filter * * @brief install a filter to route packets * * knet_h - pointer to knet_handle_t * * dst_host_filter_fn_private_data * void pointer to data that can be used to identify * the callback. * * dst_host_filter_fn - * is a callback function that is invoked every time * a packet hits datafd (see knet_handle_new(3)). * the function allows users to tell libknet where the * packet has to be delivered. * * const unsigned char *outdata - is a pointer to the * current packet * ssize_t outdata_len - length of the above data * uint8_t tx_rx - filter is called on tx or rx * (KNET_NOTIFY_TX, KNET_NOTIFY_RX) * knet_node_id_t this_host_id - host_id processing the packet * knet_node_id_t src_host_id - host_id that generated the * packet * knet_node_id_t *dst_host_ids - array of KNET_MAX_HOST knet_node_id_t * where to store the destinations * size_t *dst_host_ids_entries - number of hosts to send the message * * dst_host_filter_fn should return * -1 on error, packet is discarded. * 0 packet is unicast and should be sent to dst_host_ids and there are * dst_host_ids_entries in the buffer. * 1 packet is broadcast/multicast and is sent all hosts. * contents of dst_host_ids and dst_host_ids_entries are ignored. * (see also kronosnetd/etherfilter.* for an example that filters based * on ether protocol) * * @return * knet_handle_enable_filter returns * 0 on success * -1 on error and errno is set. */ int knet_handle_enable_filter(knet_handle_t knet_h, void *dst_host_filter_fn_private_data, int (*dst_host_filter_fn) ( void *private_data, const unsigned char *outdata, ssize_t outdata_len, uint8_t tx_rx, knet_node_id_t this_host_id, knet_node_id_t src_host_id, int8_t *channel, knet_node_id_t *dst_host_ids, size_t *dst_host_ids_entries)); /** * knet_handle_setfwd * * @brief Start packet forwarding * * knet_h - pointer to knet_handle_t * * enable - set to 1 to allow data forwarding, 0 to disable data forwarding. * * @return * knet_handle_setfwd returns * 0 on success * -1 on error and errno is set. * * By default data forwarding is off and no traffic will pass through knet until * it is set on. */ int knet_handle_setfwd(knet_handle_t knet_h, unsigned int enabled); #define KNET_PMTUD_DEFAULT_INTERVAL 60 /** * knet_handle_pmtud_setfreq * * @brief Set the interval between PMTUd scans * * knet_h - pointer to knet_handle_t * * interval - define the interval in seconds between PMTUd scans * range from 1 to 86400 (24h) * * @return * knet_handle_pmtud_setfreq returns * 0 on success * -1 on error and errno is set. * * default interval is 60. */ int knet_handle_pmtud_setfreq(knet_handle_t knet_h, unsigned int interval); /** * knet_handle_pmtud_getfreq * * @brief Get the interval between PMTUd scans * * knet_h - pointer to knet_handle_t * * interval - pointer where to store the current interval value * * @return * knet_handle_pmtud_setfreq returns * 0 on success * -1 on error and errno is set. */ int knet_handle_pmtud_getfreq(knet_handle_t knet_h, unsigned int *interval); /** * knet_handle_enable_pmtud_notify * * @brief install a callback to receive PMTUd changes * * knet_h - pointer to knet_handle_t * * pmtud_notify_fn_private_data * void pointer to data that can be used to identify * the callback. * * pmtud_notify_fn * is a callback function that is invoked every time * a path MTU size change is detected. * The function allows libknet to notify the user * of data MTU, that's the max value that can be send * onwire without fragmentation. The data MTU will always * be lower than real link MTU because it accounts for * protocol overhead, knet packet header and (if configured) * crypto overhead, * This function MUST NEVER block or add substantial delays. * * @return * knet_handle_enable_pmtud_notify returns * 0 on success * -1 on error and errno is set. */ int knet_handle_enable_pmtud_notify(knet_handle_t knet_h, void *pmtud_notify_fn_private_data, void (*pmtud_notify_fn) ( void *private_data, unsigned int data_mtu)); /** * knet_handle_pmtud_get * * @brief Get the current data MTU * * knet_h - pointer to knet_handle_t * * data_mtu - pointer where to store data_mtu * * @return * knet_handle_pmtud_get returns * 0 on success * -1 on error and errno is set. */ int knet_handle_pmtud_get(knet_handle_t knet_h, unsigned int *data_mtu); #define KNET_MIN_KEY_LEN 256 #define KNET_MAX_KEY_LEN 4096 struct knet_handle_crypto_cfg { char crypto_model[16]; char crypto_cipher_type[16]; char crypto_hash_type[16]; unsigned char private_key[KNET_MAX_KEY_LEN]; unsigned int private_key_len; }; /** * knet_handle_crypto * * @brief set up packet cryptographic signing & encryption * * knet_h - pointer to knet_handle_t * * knet_handle_crypto_cfg - * pointer to a knet_handle_crypto_cfg structure * * crypto_model should contain the model name. * Currently only "openssl" and "nss" are supported. * Setting to "none" will disable crypto. * * crypto_cipher_type * should contain the cipher algo name. * It can be set to "none" to disable * encryption. * Currently supported by "nss" model: * "3des", "aes128", "aes192" and "aes256". * "openssl" model supports more modes and it strictly * depends on the openssl build. See: EVP_get_cipherbyname * openssl API call for details. * * crypto_hash_type * should contain the hashing algo name. * It can be set to "none" to disable * hashing. * Currently supported by "nss" model: * "md5", "sha1", "sha256", "sha384" and "sha512". * "openssl" model supports more modes and it strictly * depends on the openssl build. See: EVP_get_digestbyname * openssl API call for details. * * private_key will contain the private shared key. * It has to be at least KNET_MIN_KEY_LEN long. * * private_key_len * length of the provided private_key. * * Implementation notes/current limitations: * - enabling crypto, will increase latency as packets have * to processed. * - enabling crypto might reduce the overall throughtput * due to crypto data overhead. * - re-keying is not implemented yet. * - private/public key encryption/hashing is not currently * planned. * - crypto key must be the same for all hosts in the same * knet instance. * - it is safe to call knet_handle_crypto multiple times at runtime. * The last config will be used. * IMPORTANT: a call to knet_handle_crypto can fail due to: * 1) failure to obtain locking * 2) errors to initializing the crypto level. * This can happen even in subsequent calls to knet_handle_crypto. * A failure in crypto init, might leave your traffic unencrypted! * It's best to stop data forwarding (see knet_handle_setfwd(3)), change crypto config, * start forward again. * * @return * knet_handle_crypto returns: * @retval 0 on success * @retval -1 on error and errno is set. * @retval -2 on crypto subsystem initialization error. No errno is provided at the moment (yet). */ int knet_handle_crypto(knet_handle_t knet_h, struct knet_handle_crypto_cfg *knet_handle_crypto_cfg); #define KNET_COMPRESS_THRESHOLD 100 struct knet_handle_compress_cfg { char compress_model[16]; uint32_t compress_threshold; int compress_level; }; /** * knet_handle_compress * * @brief Set up packet compression * * knet_h - pointer to knet_handle_t * * knet_handle_compress_cfg - * pointer to a knet_handle_compress_cfg structure * * compress_model contains the model name. * See "compress_level" for the list of accepted values. - * The "none" value disables compression. + * Setting the value to "none" disables compression. * * compress_threshold * tells the transmission thread to NOT compress * any packets that are smaller than the value * indicated. Default 100 bytes. * Set to 0 to reset to the default. * Set to 1 to compress everything. * Max accepted value is KNET_MAX_PACKET_SIZE. * * compress_level is the "level" parameter for most models: * zlib: 0 (no compression), 1 (minimal) .. 9 (max compression). * lz4: 1 (max compression)... 9 (fastest compression). * lz4hc: 1 (min compression) ... LZ4HC_MAX_CLEVEL (16) or LZ4HC_CLEVEL_MAX (12) * depending on the version of lz4hc libknet was built with. * lzma: 0 (minimal) .. 9 (max compression) * bzip2: 1 (minimal) .. 9 (max compression) * For lzo2 it selects the algorithm to use: * 1 : lzo1x_1_compress (default) * 11 : lzo1x_1_11_compress * 12 : lzo1x_1_12_compress * 15 : lzo1x_1_15_compress * 999: lzo1x_999_compress * Other values select the default algorithm. * Please refer to the documentation of the respective * compression library for guidance about setting this * value. * * Implementation notes: * - it is possible to enable/disable compression at any time. * - nodes can be using a different compression algorithm at any time. * - knet does NOT implement the compression algorithm directly. it relies * on external libraries for this functionality. Please read * the libraries man pages to figure out which algorithm/compression * level is best for the data you are planning to transmit. * * @return * knet_handle_compress returns * 0 on success * -1 on error and errno is set. EINVAL means that either the model or the * level are not supported. */ int knet_handle_compress(knet_handle_t knet_h, struct knet_handle_compress_cfg *knet_handle_compress_cfg); struct knet_handle_stats { size_t size; uint64_t tx_uncompressed_packets; uint64_t tx_compressed_packets; uint64_t tx_compressed_original_bytes; uint64_t tx_compressed_size_bytes; uint64_t tx_compress_time_ave; uint64_t tx_compress_time_min; uint64_t tx_compress_time_max; uint64_t rx_compressed_packets; uint64_t rx_compressed_original_bytes; uint64_t rx_compressed_size_bytes; uint64_t rx_compress_time_ave; uint64_t rx_compress_time_min; uint64_t rx_compress_time_max; /* Overhead times, measured in usecs */ uint64_t tx_crypt_packets; uint64_t tx_crypt_byte_overhead; uint64_t tx_crypt_time_ave; uint64_t tx_crypt_time_min; uint64_t tx_crypt_time_max; uint64_t rx_crypt_packets; uint64_t rx_crypt_time_ave; uint64_t rx_crypt_time_min; uint64_t rx_crypt_time_max; }; /** * knet_handle_get_stats * * @brief Get statistics for compression & crypto * * knet_h - pointer to knet_handle_t * * knet_handle_stats * pointer to a knet_handle_stats structure * * struct_size * size of knet_handle_stats structure to allow * for backwards compatibility. libknet will only * copy this much data into the stats structure * so that older callers will not get overflowed if * new fields are added. * * @return * 0 on success * -1 on error and errno is set. * */ int knet_handle_get_stats(knet_handle_t knet_h, struct knet_handle_stats *stats, size_t struct_size); /* * Tell knet_handle_clear_stats whether to clear just the handle stats * or all of them. */ #define KNET_CLEARSTATS_HANDLE_ONLY 1 #define KNET_CLEARSTATS_HANDLE_AND_LINK 2 /** * knet_handle_clear_stats * * @brief Clear knet stats, link and/or handle * * knet_h - pointer to knet_handle_t * * clear_option - Which stats to clear, must be one of * * KNET_CLEARSTATS_HANDLE_ONLY or * KNET_CLEARSTATS_HANDLE_AND_LINK * * @return * 0 on success * -1 on error and errno is set. * */ int knet_handle_clear_stats(knet_handle_t knet_h, int clear_option); struct knet_crypto_info { const char *name; /* openssl,nss,etc.. */ uint8_t properties; /* currently unused */ char pad[256]; /* currently unused */ }; /** * knet_get_crypto_list * * @brief Get a list of supported crypto libraries * * crypto_list - array of struct knet_crypto_info * * If NULL then only the number of structs is returned in crypto_list_entries * to allow the caller to allocate sufficient space. * libknet does not allow more than 256 crypto methods at the moment. * it is safe to allocate 256 structs to avoid calling * knet_get_crypto_list twice. * * crypto_list_entries - returns the number of structs in crypto_list * * @return * knet_get_crypto_list returns * 0 on success * -1 on error and errno is set. */ int knet_get_crypto_list(struct knet_crypto_info *crypto_list, size_t *crypto_list_entries); struct knet_compress_info { const char *name; /* bzip2, lz4, etc.. */ uint8_t properties; /* currently unused */ char pad[256]; /* currently unused */ }; /** * knet_get_compress_list * * @brief Get a list of support compression types * * compress_list - array of struct knet_compress_info * * If NULL then only the number of structs is returned in compress_list_entries * to allow the caller to allocate sufficient space. * libknet does not allow more than 256 compress methods at the moment. * it is safe to allocate 256 structs to avoid calling * knet_get_compress_list twice. * * compress_list_entries - returns the number of structs in compress_list * * @return * knet_get_compress_list returns * 0 on success * -1 on error and errno is set. */ int knet_get_compress_list(struct knet_compress_info *compress_list, size_t *compress_list_entries); /* * host structs/API calls */ /** * knet_host_add * * @brief Add a new host ID to knet * * knet_h - pointer to knet_handle_t * * host_id - each host in a knet is identified with a unique ID * (see also knet_handle_new(3)) * * @return * knet_host_add returns: * 0 on success * -1 on error and errno is set. */ int knet_host_add(knet_handle_t knet_h, knet_node_id_t host_id); /** * knet_host_remove * * @brief Remove a host ID from knet * * knet_h - pointer to knet_handle_t * * host_id - each host in a knet is identified with a unique ID * (see also knet_handle_new(3)) * * @return * knet_host_remove returns: * 0 on success * -1 on error and errno is set. */ int knet_host_remove(knet_handle_t knet_h, knet_node_id_t host_id); /** * knet_host_set_name * * @brief Set the name of a knet host * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * name - this name will be used for pretty logging and eventually * search for hosts (see also knet_handle_host_get_name(2) and knet_handle_host_get_id(3)). * Only up to KNET_MAX_HOST_LEN - 1 bytes will be accepted and * name has to be unique for each host. * * @return * knet_host_set_name returns: * 0 on success * -1 on error and errno is set. */ int knet_host_set_name(knet_handle_t knet_h, knet_node_id_t host_id, const char *name); /** * knet_host_get_name_by_host_id * * @brief Get the name of a host given its ID * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * name - pointer to a preallocated buffer of at least size KNET_MAX_HOST_LEN * where the current host name will be stored * (as set by knet_host_set_name or default by knet_host_add) * * @return * knet_host_get_name_by_host_id returns: * 0 on success * -1 on error and errno is set (name is left untouched) */ int knet_host_get_name_by_host_id(knet_handle_t knet_h, knet_node_id_t host_id, char *name); /** * knet_host_get_id_by_host_name * * @brief Get the ID of a host given its name * * knet_h - pointer to knet_handle_t * * name - name to lookup, max len KNET_MAX_HOST_LEN * * host_id - where to store the result * * @return * knet_host_get_id_by_host_name returns: * 0 on success * -1 on error and errno is set. */ int knet_host_get_id_by_host_name(knet_handle_t knet_h, const char *name, knet_node_id_t *host_id); /** * knet_host_get_host_list * * @brief Get a list of hosts known to knet * * knet_h - pointer to knet_handle_t * * host_ids - array of at lest KNET_MAX_HOST size * * host_ids_entries - * number of entries writted in host_ids * * @return * knet_host_get_host_list returns * 0 on success * -1 on error and errno is set. */ int knet_host_get_host_list(knet_handle_t knet_h, knet_node_id_t *host_ids, size_t *host_ids_entries); /* * define switching policies */ #define KNET_LINK_POLICY_PASSIVE 0 #define KNET_LINK_POLICY_ACTIVE 1 #define KNET_LINK_POLICY_RR 2 /** * knet_host_set_policy * * knet_h - pointer to knet_handle_t * * @brief Set the switching policy for a host's links * * host_id - see knet_host_add(3) * * policy - there are currently 3 kind of simple switching policies * based on link configuration. * KNET_LINK_POLICY_PASSIVE - the active link with the lowest * priority will be used. * if one or more active links share * the same priority, the one with * lowest link_id will be used. * * KNET_LINK_POLICY_ACTIVE - all active links will be used * simultaneously to send traffic. * link priority is ignored. * * KNET_LINK_POLICY_RR - round-robin policy, every packet * will be send on a different active * link. * * @return * knet_host_set_policy returns * 0 on success * -1 on error and errno is set. */ int knet_host_set_policy(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t policy); /** * knet_host_get_policy * * @brief Get the switching policy for a host's links * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * policy - will contain the current configured switching policy. * Default is passive when creating a new host. * * @return * knet_host_get_policy returns * 0 on success * -1 on error and errno is set. */ int knet_host_get_policy(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t *policy); /** * knet_host_enable_status_change_notify * * @brief Install a callback to get host status change events * * knet_h - pointer to knet_handle_t * * host_status_change_notify_fn_private_data - * void pointer to data that can be used to identify * the callback * * host_status_change_notify_fn - * is a callback function that is invoked every time * there is a change in the host status. * host status is identified by: * - reachable, this host can send/receive data to/from host_id * - remote, 0 if the host_id is connected locally or 1 if * the there is one or more knet host(s) in between. * NOTE: re-switching is NOT currently implemented, * but this is ready for future and can avoid * an API/ABI breakage later on. * - external, 0 if the host_id is configured locally or 1 if * it has been added from remote nodes config. * NOTE: dynamic topology is NOT currently implemented, * but this is ready for future and can avoid * an API/ABI breakage later on. * This function MUST NEVER block or add substantial delays. * * @return * knet_host_status_change_notify returns * 0 on success * -1 on error and errno is set. */ int knet_host_enable_status_change_notify(knet_handle_t knet_h, void *host_status_change_notify_fn_private_data, void (*host_status_change_notify_fn) ( void *private_data, knet_node_id_t host_id, uint8_t reachable, uint8_t remote, uint8_t external)); /* * define host status structure for quick lookup * struct is in flux as more stats will be added soon * * reachable host_id can be seen either directly connected * or via another host_id * * remote 0 = node is connected locally, 1 is visible via * via another host_id * * external 0 = node is configured/known locally, * 1 host_id has been received via another host_id */ struct knet_host_status { uint8_t reachable; uint8_t remote; uint8_t external; /* add host statistics */ }; /** * knet_host_status_get * * @brief Get the status of a host * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * status - pointer to knet_host_status struct * * @return * knet_handle_pmtud_get returns * 0 on success * -1 on error and errno is set. */ int knet_host_get_status(knet_handle_t knet_h, knet_node_id_t host_id, struct knet_host_status *status); /* * link structs/API calls * * every host allocated/managed by knet_host_* has * KNET_MAX_LINK structures to define the network * paths that connect 2 hosts. * * Each link is identified by a link_id that has a * values between 0 and KNET_MAX_LINK - 1. * * KNOWN LIMITATIONS: * * - let's assume the scenario where two hosts are connected * with any number of links. link_id must match on both sides. * If host_id 0 link_id 0 is configured to connect IP1 to IP2 and * host_id 0 link_id 1 is configured to connect IP3 to IP4, * host_id 1 link_id 0 _must_ connect IP2 to IP1 and likewise * host_id 1 link_id 1 _must_ connect IP4 to IP3. * We might be able to lift this restriction in future, by using * other data to determine src/dst link_id, but for now, deal with it. */ /* * commodity functions to convert strings to sockaddr and viceversa */ /** * knet_strtoaddr * * @brief Convert a hostname string to an address * * host - IPaddr/hostname to convert * be aware only the first IP address will be returned * in case a hostname resolves to multiple IP * * port - port to connect to * * ss - sockaddr_storage where to store the converted data * * sslen - len of the sockaddr_storage * * @return * knet_strtoaddr returns same error codes as getaddrinfo * */ int knet_strtoaddr(const char *host, const char *port, struct sockaddr_storage *ss, socklen_t sslen); /** * knet_addrtostr * * @brief Convert an address to a host name * * ss - sockaddr_storage to convert * * sslen - len of the sockaddr_storage * * host - IPaddr/hostname where to store data * (recommended size: KNET_MAX_HOST_LEN) * * port - port buffer where to store data * (recommended size: KNET_MAX_PORT_LEN) * * @return * knet_strtoaddr returns same error codes as getnameinfo */ int knet_addrtostr(const struct sockaddr_storage *ss, socklen_t sslen, char *addr_buf, size_t addr_buf_size, char *port_buf, size_t port_buf_size); #define KNET_TRANSPORT_LOOPBACK 0 #define KNET_TRANSPORT_UDP 1 #define KNET_TRANSPORT_SCTP 2 #define KNET_MAX_TRANSPORTS UINT8_MAX /* * The Loopback transport is only valid for connections to localhost, the host * with the same node_id specified in knet_handle_new(). Only one link of this * type is allowed. Data sent down a LOOPBACK link will be copied directly from * the knet send datafd to the knet receive datafd so the application must be set * up to take data from that socket at least as often as it is sent or deadlocks * could occur. If used, a LOOPBACK link must be the only link configured to the * local host. */ struct knet_transport_info { const char *name; /* UDP/SCTP/etc... */ uint8_t id; /* value that can be used for link_set_config */ uint8_t properties; /* currently unused */ char pad[256]; /* currently unused */ }; /** * knet_get_transport_list * * @brief Get a list of the transports support by this build of knet * * transport_list - an array of struct transport_info that must be * at least of size struct transport_info * KNET_MAX_TRANSPORTS * * transport_list_entries - pointer to a size_t where to store how many transports * are available in this build of libknet. * * @return * knet_get_transport_list returns * 0 on success * -1 on error and errno is set. */ int knet_get_transport_list(struct knet_transport_info *transport_list, size_t *transport_list_entries); /** * knet_get_transport_name_by_id * * @brief Get a transport name from its ID number * * transport - one of the KNET_TRANSPORT_xxx constants * * @return * knet_get_transport_name_by_id returns: * * @retval pointer to the name on success or * @retval NULL on error and errno is set. */ const char *knet_get_transport_name_by_id(uint8_t transport); /** * knet_get_transport_id_by_name * * @brief Get a transport ID from its name * * name - transport name (UDP/SCTP/etc) * * @return * knet_get_transport_name_by_id returns: * * @retval KNET_MAX_TRANSPORTS on error and errno is set accordingly * @retval KNET_TRANSPORT_xxx on success. */ uint8_t knet_get_transport_id_by_name(const char *name); #define KNET_TRANSPORT_DEFAULT_RECONNECT_INTERVAL 1000 /** * knet_handle_set_transport_reconnect_interval * * @brief Set the interval between transport attempts to reconnect a failed link * * knet_h - pointer to knet_handle_t * * msecs - milliseconds * * @return * knet_handle_set_transport_reconnect_interval returns * 0 on success * -1 on error and errno is set. */ int knet_handle_set_transport_reconnect_interval(knet_handle_t knet_h, uint32_t msecs); /** * knet_handle_get_transport_reconnect_interval * * @brief Get the interval between transport attempts to reconnect a failed link * * knet_h - pointer to knet_handle_t * * msecs - milliseconds * * @return * knet_handle_get_transport_reconnect_interval returns * 0 on success * -1 on error and errno is set. */ int knet_handle_get_transport_reconnect_interval(knet_handle_t knet_h, uint32_t *msecs); /** * knet_link_set_config * * @brief Configure the link to a host * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * transport - one of the KNET_TRANSPORT_xxx constants * * src_addr - sockaddr_storage that can be either IPv4 or IPv6 * * dst_addr - sockaddr_storage that can be either IPv4 or IPv6 * this can be null if we don't know the incoming * IP address/port and the link will remain quiet * till the node on the other end will initiate a * connection * * flags - KNET_LINK_FLAG_* * * @return * knet_link_set_config returns * 0 on success * -1 on error and errno is set. */ int knet_link_set_config(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id, uint8_t transport, struct sockaddr_storage *src_addr, struct sockaddr_storage *dst_addr, uint64_t flags); /** * knet_link_get_config * * @brief Get the link configutation information * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * transport - see knet_link_set_config(3) * * src_addr - sockaddr_storage that can be either IPv4 or IPv6 * * dst_addr - sockaddr_storage that can be either IPv4 or IPv6 * * dynamic - 0 if dst_addr is static or 1 if dst_addr is dynamic. * In case of 1, dst_addr can be NULL and it will be left * untouched. * * flags - KNET_LINK_FLAG_* * * @return * knet_link_get_config returns * 0 on success. * -1 on error and errno is set. */ int knet_link_get_config(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id, uint8_t *transport, struct sockaddr_storage *src_addr, struct sockaddr_storage *dst_addr, uint8_t *dynamic, uint64_t *flags); /** * knet_link_clear_config * * @brief Clear link information and disconnect the link * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * @return * knet_link_clear_config returns * 0 on success. * -1 on error and errno is set. */ int knet_link_clear_config(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id); /** * knet_link_set_enable * * @brief Enable traffic on a link * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * enabled - 0 disable the link, 1 enable the link * * @return * knet_link_set_enable returns * 0 on success * -1 on error and errno is set. */ int knet_link_set_enable(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id, unsigned int enabled); /** * knet_link_get_enable * * @brief Find out whether a link is enabled or not * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * enabled - 0 disable the link, 1 enable the link * * @return * knet_link_get_enable returns * 0 on success * -1 on error and errno is set. */ int knet_link_get_enable(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id, unsigned int *enabled); #define KNET_LINK_DEFAULT_PING_INTERVAL 1000 /* 1 second */ #define KNET_LINK_DEFAULT_PING_TIMEOUT 2000 /* 2 seconds */ #define KNET_LINK_DEFAULT_PING_PRECISION 2048 /* samples */ /** * knet_link_set_ping_timers * * @brief Set the ping timers for a link * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * interval - specify the ping interval in milliseconds. * * timeout - if no pong is received within this time, * the link is declared dead, in milliseconds. * NOTE: in future it will be possible to set timeout to 0 * for an autocalculated timeout based on interval, pong_count * and latency. The API already accept 0 as value and it will * return ENOSYS / -1. Once the automatic calculation feature * will be implemented, this call will only return EINVAL * for incorrect values. * * precision - how many values of latency are used to calculate * the average link latency (see also knet_link_get_status(3)) * * @return * knet_link_set_ping_timers returns * 0 on success * -1 on error and errno is set. */ int knet_link_set_ping_timers(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id, time_t interval, time_t timeout, unsigned int precision); /** * knet_link_get_ping_timers * * @brief Get the ping timers for a link * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * interval - ping interval * * timeout - if no pong is received within this time, * the link is declared dead * * precision - how many values of latency are used to calculate * the average link latency (see also knet_link_get_status(3)) * * @return * knet_link_get_ping_timers returns * 0 on success * -1 on error and errno is set. */ int knet_link_get_ping_timers(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id, time_t *interval, time_t *timeout, unsigned int *precision); #define KNET_LINK_DEFAULT_PONG_COUNT 5 /** * knet_link_set_pong_count * * @brief Set the pong count for a link * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * pong_count - how many valid ping/pongs before a link is marked UP. * default: 5, value should be > 0 * * @return * knet_link_set_pong_count returns * 0 on success * -1 on error and errno is set. */ int knet_link_set_pong_count(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id, uint8_t pong_count); /** * knet_link_get_pong_count * * @brief Get the pong count for a link * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * pong_count - how many valid ping/pongs before a link is marked UP. * default: 5, value should be > 0 * * @return * knet_link_get_pong_count returns * 0 on success * -1 on error and errno is set. */ int knet_link_get_pong_count(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id, uint8_t *pong_count); /** * knet_link_set_priority * * @brief Set the priority for a link * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * priority - specify the switching priority for this link * see also knet_host_set_policy * * @return * knet_link_set_priority returns * 0 on success * -1 on error and errno is set. */ int knet_link_set_priority(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id, uint8_t priority); /** * knet_link_get_priority * * @brief Get the priority for a link * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * priority - gather the switching priority for this link * see also knet_host_set_policy * * @return * knet_link_get_priority returns * 0 on success * -1 on error and errno is set. */ int knet_link_get_priority(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id, uint8_t *priority); /** * knet_link_get_link_list * * @brief Get a list of links connecting a host * * knet_h - pointer to knet_handle_t * * link_ids - array of at lest KNET_MAX_LINK size * with the list of configured links for a certain host. * * link_ids_entries - * number of entries contained in link_ids * * @return * knet_link_get_link_list returns * 0 on success * -1 on error and errno is set. */ int knet_link_get_link_list(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t *link_ids, size_t *link_ids_entries); /* * define link status structure for quick lookup * * src/dst_{ipaddr,port} strings are filled by * getnameinfo(3) when configuring the link. * if the link is dynamic (see knet_link_set_config(3)) * dst_ipaddr/port will contain ipaddr/port of the currently * connected peer or "Unknown" if it was not possible * to determine the ipaddr/port at runtime. * * enabled see also knet_link_set/get_enable. * * connected the link is connected to a peer and ping/pong traffic * is flowing. * * dynconnected the link has dynamic ip on the other end, and * we can see the other host is sending pings to us. * * latency average latency of this link * see also knet_link_set/get_timeout. * * pong_last if the link is down, this value tells us how long * ago this link was active. A value of 0 means that the link * has never been active. * * knet_link_stats structure that contains details statistics for the link */ #define MAX_LINK_EVENTS 16 struct knet_link_stats { /* onwire values */ uint64_t tx_data_packets; uint64_t rx_data_packets; uint64_t tx_data_bytes; uint64_t rx_data_bytes; uint64_t rx_ping_packets; uint64_t tx_ping_packets; uint64_t rx_ping_bytes; uint64_t tx_ping_bytes; uint64_t rx_pong_packets; uint64_t tx_pong_packets; uint64_t rx_pong_bytes; uint64_t tx_pong_bytes; uint64_t rx_pmtu_packets; uint64_t tx_pmtu_packets; uint64_t rx_pmtu_bytes; uint64_t tx_pmtu_bytes; /* Only filled in when requested */ uint64_t tx_total_packets; uint64_t rx_total_packets; uint64_t tx_total_bytes; uint64_t rx_total_bytes; uint64_t tx_total_errors; uint64_t tx_total_retries; uint32_t tx_pmtu_errors; uint32_t tx_pmtu_retries; uint32_t tx_ping_errors; uint32_t tx_ping_retries; uint32_t tx_pong_errors; uint32_t tx_pong_retries; uint32_t tx_data_errors; uint32_t tx_data_retries; /* measured in usecs */ uint32_t latency_min; uint32_t latency_max; uint32_t latency_ave; uint32_t latency_samples; /* how many times the link has been going up/down */ uint32_t down_count; uint32_t up_count; /* * circular buffer of time_t structs collecting the history * of up/down events on this link. * the index indicates current/last event. * it is safe to walk back the history by decreasing the index */ time_t last_up_times[MAX_LINK_EVENTS]; time_t last_down_times[MAX_LINK_EVENTS]; int8_t last_up_time_index; int8_t last_down_time_index; /* Always add new stats at the end */ }; struct knet_link_status { size_t size; /* For ABI checking */ char src_ipaddr[KNET_MAX_HOST_LEN]; char src_port[KNET_MAX_PORT_LEN]; char dst_ipaddr[KNET_MAX_HOST_LEN]; char dst_port[KNET_MAX_PORT_LEN]; uint8_t enabled; /* link is configured and admin enabled for traffic */ uint8_t connected; /* link is connected for data (local view) */ uint8_t dynconnected; /* link has been activated by remote dynip */ unsigned long long latency; /* average latency computed by fix/exp */ struct timespec pong_last; unsigned int mtu; /* current detected MTU on this link */ unsigned int proto_overhead; /* contains the size of the IP protocol, knet headers and * crypto headers (if configured). This value is filled in * ONLY after the first PMTUd run on that given link, * and can change if link configuration or crypto configuration * changes at runtime. * WARNING: in general mtu + proto_overhead might or might * not match the output of ifconfig mtu due to crypto * requirements to pad packets to some specific boundaries. */ /* Link statistics */ struct knet_link_stats stats; }; /** * knet_link_get_status * * @brief Get the status (and statistics) for a link * * knet_h - pointer to knet_handle_t * * host_id - see knet_host_add(3) * * link_id - see knet_link_set_config(3) * * status - pointer to knet_link_status struct * * struct_size - max size of knet_link_status - allows library to * add fields without ABI change. Returned structure * will be truncated to this length and .size member * indicates the full size. * * @return * knet_link_get_status returns * 0 on success * -1 on error and errno is set. */ int knet_link_get_status(knet_handle_t knet_h, knet_node_id_t host_id, uint8_t link_id, struct knet_link_status *status, size_t struct_size); /* * logging structs/API calls */ /* * libknet is composed of several subsystems. In order * to easily distinguish log messages coming from different * places, each subsystem has its own ID. * * 0-19 config/management * 20-39 internal threads * 40-59 transports * 60-69 crypto implementations */ #define KNET_SUB_COMMON 0 /* common.c */ #define KNET_SUB_HANDLE 1 /* handle.c alloc/dealloc config changes */ #define KNET_SUB_HOST 2 /* host add/del/modify */ #define KNET_SUB_LISTENER 3 /* listeners add/del/modify... */ #define KNET_SUB_LINK 4 /* link add/del/modify */ #define KNET_SUB_TRANSPORT 5 /* Transport common */ #define KNET_SUB_CRYPTO 6 /* crypto.c config generic layer */ #define KNET_SUB_COMPRESS 7 /* compress.c config generic layer */ #define KNET_SUB_FILTER 19 /* allocated for users to log from dst_filter */ #define KNET_SUB_DSTCACHE 20 /* switching thread (destination cache handling) */ #define KNET_SUB_HEARTBEAT 21 /* heartbeat thread */ #define KNET_SUB_PMTUD 22 /* Path MTU Discovery thread */ #define KNET_SUB_TX 23 /* send to link thread */ #define KNET_SUB_RX 24 /* recv from link thread */ #define KNET_SUB_TRANSP_BASE 40 /* Base log level for transports */ #define KNET_SUB_TRANSP_LOOPBACK (KNET_SUB_TRANSP_BASE + KNET_TRANSPORT_LOOPBACK) #define KNET_SUB_TRANSP_UDP (KNET_SUB_TRANSP_BASE + KNET_TRANSPORT_UDP) #define KNET_SUB_TRANSP_SCTP (KNET_SUB_TRANSP_BASE + KNET_TRANSPORT_SCTP) #define KNET_SUB_NSSCRYPTO 60 /* nsscrypto.c */ #define KNET_SUB_OPENSSLCRYPTO 61 /* opensslcrypto.c */ #define KNET_SUB_ZLIBCOMP 70 /* compress_zlib.c */ #define KNET_SUB_LZ4COMP 71 /* compress_lz4.c */ #define KNET_SUB_LZ4HCCOMP 72 /* compress_lz4.c */ #define KNET_SUB_LZO2COMP 73 /* compress_lzo.c */ #define KNET_SUB_LZMACOMP 74 /* compress_lzma.c */ #define KNET_SUB_BZIP2COMP 75 /* compress_bzip2.c */ #define KNET_SUB_UNKNOWN UINT8_MAX - 1 #define KNET_MAX_SUBSYSTEMS UINT8_MAX /* * Convert between subsystem IDs and names */ /** * knet_log_get_subsystem_name * * @brief Get a logging system name from its numeric ID * * @return * returns internal name of the subsystem or "common" */ const char *knet_log_get_subsystem_name(uint8_t subsystem); /** * knet_log_get_subsystem_id * * @brief Get a logging system ID from its name * * @return * returns internal ID of the subsystem or KNET_SUB_COMMON */ uint8_t knet_log_get_subsystem_id(const char *name); /* * 4 log levels are enough for everybody */ #define KNET_LOG_ERR 0 /* unrecoverable errors/conditions */ #define KNET_LOG_WARN 1 /* recoverable errors/conditions */ #define KNET_LOG_INFO 2 /* info, link up/down, config changes.. */ #define KNET_LOG_DEBUG 3 /* * Convert between log level values and names */ /** * knet_log_get_loglevel_name * * @brief Get a logging level name from its numeric ID * * @return * returns internal name of the log level or "ERROR" for unknown values */ const char *knet_log_get_loglevel_name(uint8_t level); /** * knet_log_get_loglevel_id * * @brief Get a logging level ID from its name * * @return * returns internal log level ID or KNET_LOG_ERR for invalid names */ uint8_t knet_log_get_loglevel_id(const char *name); /* * every log message is composed by a text message (including a trailing \n) * and message level/subsystem IDs. * In order to make debugging easier it is possible to send those packets * straight to stdout/stderr (see knet_bench.c stdout option). */ #define KNET_MAX_LOG_MSG_SIZE 256 struct knet_log_msg { char msg[KNET_MAX_LOG_MSG_SIZE - (sizeof(uint8_t)*2)]; uint8_t subsystem; /* KNET_SUB_* */ uint8_t msglevel; /* KNET_LOG_* */ }; /** * knet_log_set_log_level * * @brief Set the logging level for a subsystem * * knet_h - same as above * * subsystem - same as above * * level - same as above * * knet_log_set_loglevel allows fine control of log levels by subsystem. * See also knet_handle_new for defaults. * * @return * knet_log_set_loglevel returns * 0 on success * -1 on error and errno is set. */ int knet_log_set_loglevel(knet_handle_t knet_h, uint8_t subsystem, uint8_t level); /** * knet_log_get_log_level * * @brief Get the logging level for a subsystem * * knet_h - same as above * * subsystem - same as above * * level - same as above * * @return * knet_log_get_loglevel returns * 0 on success * -1 on error and errno is set. */ int knet_log_get_loglevel(knet_handle_t knet_h, uint8_t subsystem, uint8_t *level); #endif