// SPDX-License-Identifier: GPL-2.0 /* Copyright (C) B.A.T.M.A.N. contributors: * * Edo Monticelli, Antonio Quartulli */ #include "tp_meter.h" #include "main.h" #include <linux/atomic.h> #include <linux/build_bug.h> #include <linux/byteorder/generic.h> #include <linux/cache.h> #include <linux/compiler.h> #include <linux/container_of.h> #include <linux/err.h> #include <linux/etherdevice.h> #include <linux/gfp.h> #include <linux/if_ether.h> #include <linux/init.h> #include <linux/jiffies.h> #include <linux/kref.h> #include <linux/kthread.h> #include <linux/limits.h> #include <linux/list.h> #include <linux/minmax.h> #include <linux/netdevice.h> #include <linux/param.h> #include <linux/printk.h> #include <linux/random.h> #include <linux/rculist.h> #include <linux/rcupdate.h> #include <linux/sched.h> #include <linux/skbuff.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/stddef.h> #include <linux/string.h> #include <linux/timer.h> #include <linux/wait.h> #include <linux/workqueue.h> #include <uapi/linux/batadv_packet.h> #include <uapi/linux/batman_adv.h> #include "hard-interface.h" #include "log.h" #include "netlink.h" #include "originator.h" #include "send.h" /** * BATADV_TP_DEF_TEST_LENGTH - Default test length if not specified by the user * in milliseconds */ #define BATADV_TP_DEF_TEST_LENGTH … /** * BATADV_TP_AWND - Advertised window by the receiver (in bytes) */ #define BATADV_TP_AWND … /** * BATADV_TP_RECV_TIMEOUT - Receiver activity timeout. If the receiver does not * get anything for such amount of milliseconds, the connection is killed */ #define BATADV_TP_RECV_TIMEOUT … /** * BATADV_TP_MAX_RTO - Maximum sender timeout. If the sender RTO gets beyond * such amount of milliseconds, the receiver is considered unreachable and the * connection is killed */ #define BATADV_TP_MAX_RTO … /** * BATADV_TP_FIRST_SEQ - First seqno of each session. The number is rather high * in order to immediately trigger a wrap around (test purposes) */ #define BATADV_TP_FIRST_SEQ … /** * BATADV_TP_PLEN - length of the payload (data after the batadv_unicast header) * to simulate */ #define BATADV_TP_PLEN … static u8 batadv_tp_prerandom[4096] __read_mostly; /** * batadv_tp_session_cookie() - generate session cookie based on session ids * @session: TP session identifier * @icmp_uid: icmp pseudo uid of the tp session * * Return: 32 bit tp_meter session cookie */ static u32 batadv_tp_session_cookie(const u8 session[2], u8 icmp_uid) { … } /** * batadv_tp_cwnd() - compute the new cwnd size * @base: base cwnd size value * @increment: the value to add to base to get the new size * @min: minimum cwnd value (usually MSS) * * Return the new cwnd size and ensure it does not exceed the Advertised * Receiver Window size. It is wrapped around safely. * For details refer to Section 3.1 of RFC5681 * * Return: new congestion window size in bytes */ static u32 batadv_tp_cwnd(u32 base, u32 increment, u32 min) { … } /** * batadv_tp_update_cwnd() - update the Congestion Windows * @tp_vars: the private data of the current TP meter session * @mss: maximum segment size of transmission * * 1) if the session is in Slow Start, the CWND has to be increased by 1 * MSS every unique received ACK * 2) if the session is in Congestion Avoidance, the CWND has to be * increased by MSS * MSS / CWND for every unique received ACK */ static void batadv_tp_update_cwnd(struct batadv_tp_vars *tp_vars, u32 mss) { … } /** * batadv_tp_update_rto() - calculate new retransmission timeout * @tp_vars: the private data of the current TP meter session * @new_rtt: new roundtrip time in msec */ static void batadv_tp_update_rto(struct batadv_tp_vars *tp_vars, u32 new_rtt) { … } /** * batadv_tp_batctl_notify() - send client status result to client * @reason: reason for tp meter session stop * @dst: destination of tp_meter session * @bat_priv: the bat priv with all the soft interface information * @start_time: start of transmission in jiffies * @total_sent: bytes acked to the receiver * @cookie: cookie of tp_meter session */ static void batadv_tp_batctl_notify(enum batadv_tp_meter_reason reason, const u8 *dst, struct batadv_priv *bat_priv, unsigned long start_time, u64 total_sent, u32 cookie) { … } /** * batadv_tp_batctl_error_notify() - send client error result to client * @reason: reason for tp meter session stop * @dst: destination of tp_meter session * @bat_priv: the bat priv with all the soft interface information * @cookie: cookie of tp_meter session */ static void batadv_tp_batctl_error_notify(enum batadv_tp_meter_reason reason, const u8 *dst, struct batadv_priv *bat_priv, u32 cookie) { … } /** * batadv_tp_list_find() - find a tp_vars object in the global list * @bat_priv: the bat priv with all the soft interface information * @dst: the other endpoint MAC address to look for * * Look for a tp_vars object matching dst as end_point and return it after * having increment the refcounter. Return NULL is not found * * Return: matching tp_vars or NULL when no tp_vars with @dst was found */ static struct batadv_tp_vars *batadv_tp_list_find(struct batadv_priv *bat_priv, const u8 *dst) { … } /** * batadv_tp_list_find_session() - find tp_vars session object in the global * list * @bat_priv: the bat priv with all the soft interface information * @dst: the other endpoint MAC address to look for * @session: session identifier * * Look for a tp_vars object matching dst as end_point, session as tp meter * session and return it after having increment the refcounter. Return NULL * is not found * * Return: matching tp_vars or NULL when no tp_vars was found */ static struct batadv_tp_vars * batadv_tp_list_find_session(struct batadv_priv *bat_priv, const u8 *dst, const u8 *session) { … } /** * batadv_tp_vars_release() - release batadv_tp_vars from lists and queue for * free after rcu grace period * @ref: kref pointer of the batadv_tp_vars */ static void batadv_tp_vars_release(struct kref *ref) { … } /** * batadv_tp_vars_put() - decrement the batadv_tp_vars refcounter and possibly * release it * @tp_vars: the private data of the current TP meter session to be free'd */ static void batadv_tp_vars_put(struct batadv_tp_vars *tp_vars) { … } /** * batadv_tp_sender_cleanup() - cleanup sender data and drop and timer * @bat_priv: the bat priv with all the soft interface information * @tp_vars: the private data of the current TP meter session to cleanup */ static void batadv_tp_sender_cleanup(struct batadv_priv *bat_priv, struct batadv_tp_vars *tp_vars) { … } /** * batadv_tp_sender_end() - print info about ended session and inform client * @bat_priv: the bat priv with all the soft interface information * @tp_vars: the private data of the current TP meter session */ static void batadv_tp_sender_end(struct batadv_priv *bat_priv, struct batadv_tp_vars *tp_vars) { … } /** * batadv_tp_sender_shutdown() - let sender thread/timer stop gracefully * @tp_vars: the private data of the current TP meter session * @reason: reason for tp meter session stop */ static void batadv_tp_sender_shutdown(struct batadv_tp_vars *tp_vars, enum batadv_tp_meter_reason reason) { … } /** * batadv_tp_sender_finish() - stop sender session after test_length was reached * @work: delayed work reference of the related tp_vars */ static void batadv_tp_sender_finish(struct work_struct *work) { … } /** * batadv_tp_reset_sender_timer() - reschedule the sender timer * @tp_vars: the private TP meter data for this session * * Reschedule the timer using tp_vars->rto as delay */ static void batadv_tp_reset_sender_timer(struct batadv_tp_vars *tp_vars) { … } /** * batadv_tp_sender_timeout() - timer that fires in case of packet loss * @t: address to timer_list inside tp_vars * * If fired it means that there was packet loss. * Switch to Slow Start, set the ss_threshold to half of the current cwnd and * reset the cwnd to 3*MSS */ static void batadv_tp_sender_timeout(struct timer_list *t) { … } /** * batadv_tp_fill_prerandom() - Fill buffer with prefetched random bytes * @tp_vars: the private TP meter data for this session * @buf: Buffer to fill with bytes * @nbytes: amount of pseudorandom bytes */ static void batadv_tp_fill_prerandom(struct batadv_tp_vars *tp_vars, u8 *buf, size_t nbytes) { … } /** * batadv_tp_send_msg() - send a single message * @tp_vars: the private TP meter data for this session * @src: source mac address * @orig_node: the originator of the destination * @seqno: sequence number of this packet * @len: length of the entire packet * @session: session identifier * @uid: local ICMP "socket" index * @timestamp: timestamp in jiffies which is replied in ack * * Create and send a single TP Meter message. * * Return: 0 on success, BATADV_TP_REASON_DST_UNREACHABLE if the destination is * not reachable, BATADV_TP_REASON_MEMORY_ERROR if the packet couldn't be * allocated */ static int batadv_tp_send_msg(struct batadv_tp_vars *tp_vars, const u8 *src, struct batadv_orig_node *orig_node, u32 seqno, size_t len, const u8 *session, int uid, u32 timestamp) { … } /** * batadv_tp_recv_ack() - ACK receiving function * @bat_priv: the bat priv with all the soft interface information * @skb: the buffer containing the received packet * * Process a received TP ACK packet */ static void batadv_tp_recv_ack(struct batadv_priv *bat_priv, const struct sk_buff *skb) { … } /** * batadv_tp_avail() - check if congestion window is not full * @tp_vars: the private data of the current TP meter session * @payload_len: size of the payload of a single message * * Return: true when congestion window is not full, false otherwise */ static bool batadv_tp_avail(struct batadv_tp_vars *tp_vars, size_t payload_len) { … } /** * batadv_tp_wait_available() - wait until congestion window becomes free or * timeout is reached * @tp_vars: the private data of the current TP meter session * @plen: size of the payload of a single message * * Return: 0 if the condition evaluated to false after the timeout elapsed, * 1 if the condition evaluated to true after the timeout elapsed, the * remaining jiffies (at least 1) if the condition evaluated to true before * the timeout elapsed, or -ERESTARTSYS if it was interrupted by a signal. */ static int batadv_tp_wait_available(struct batadv_tp_vars *tp_vars, size_t plen) { … } /** * batadv_tp_send() - main sending thread of a tp meter session * @arg: address of the related tp_vars * * Return: nothing, this function never returns */ static int batadv_tp_send(void *arg) { … } /** * batadv_tp_start_kthread() - start new thread which manages the tp meter * sender * @tp_vars: the private data of the current TP meter session */ static void batadv_tp_start_kthread(struct batadv_tp_vars *tp_vars) { … } /** * batadv_tp_start() - start a new tp meter session * @bat_priv: the bat priv with all the soft interface information * @dst: the receiver MAC address * @test_length: test length in milliseconds * @cookie: session cookie */ void batadv_tp_start(struct batadv_priv *bat_priv, const u8 *dst, u32 test_length, u32 *cookie) { … } /** * batadv_tp_stop() - stop currently running tp meter session * @bat_priv: the bat priv with all the soft interface information * @dst: the receiver MAC address * @return_value: reason for tp meter session stop */ void batadv_tp_stop(struct batadv_priv *bat_priv, const u8 *dst, u8 return_value) { … } /** * batadv_tp_reset_receiver_timer() - reset the receiver shutdown timer * @tp_vars: the private data of the current TP meter session * * start the receiver shutdown timer or reset it if already started */ static void batadv_tp_reset_receiver_timer(struct batadv_tp_vars *tp_vars) { … } /** * batadv_tp_receiver_shutdown() - stop a tp meter receiver when timeout is * reached without received ack * @t: address to timer_list inside tp_vars */ static void batadv_tp_receiver_shutdown(struct timer_list *t) { … } /** * batadv_tp_send_ack() - send an ACK packet * @bat_priv: the bat priv with all the soft interface information * @dst: the mac address of the destination originator * @seq: the sequence number to ACK * @timestamp: the timestamp to echo back in the ACK * @session: session identifier * @socket_index: local ICMP socket identifier * * Return: 0 on success, a positive integer representing the reason of the * failure otherwise */ static int batadv_tp_send_ack(struct batadv_priv *bat_priv, const u8 *dst, u32 seq, __be32 timestamp, const u8 *session, int socket_index) { … } /** * batadv_tp_handle_out_of_order() - store an out of order packet * @tp_vars: the private data of the current TP meter session * @skb: the buffer containing the received packet * * Store the out of order packet in the unacked list for late processing. This * packets are kept in this list so that they can be ACKed at once as soon as * all the previous packets have been received * * Return: true if the packed has been successfully processed, false otherwise */ static bool batadv_tp_handle_out_of_order(struct batadv_tp_vars *tp_vars, const struct sk_buff *skb) { … } /** * batadv_tp_ack_unordered() - update number received bytes in current stream * without gaps * @tp_vars: the private data of the current TP meter session */ static void batadv_tp_ack_unordered(struct batadv_tp_vars *tp_vars) { … } /** * batadv_tp_init_recv() - return matching or create new receiver tp_vars * @bat_priv: the bat priv with all the soft interface information * @icmp: received icmp tp msg * * Return: corresponding tp_vars or NULL on errors */ static struct batadv_tp_vars * batadv_tp_init_recv(struct batadv_priv *bat_priv, const struct batadv_icmp_tp_packet *icmp) { … } /** * batadv_tp_recv_msg() - process a single data message * @bat_priv: the bat priv with all the soft interface information * @skb: the buffer containing the received packet * * Process a received TP MSG packet */ static void batadv_tp_recv_msg(struct batadv_priv *bat_priv, const struct sk_buff *skb) { … } /** * batadv_tp_meter_recv() - main TP Meter receiving function * @bat_priv: the bat priv with all the soft interface information * @skb: the buffer containing the received packet */ void batadv_tp_meter_recv(struct batadv_priv *bat_priv, struct sk_buff *skb) { … } /** * batadv_tp_meter_init() - initialize global tp_meter structures */ void __init batadv_tp_meter_init(void) { … }