linux/net/tipc/node.c, branch v5.7

tipc: Fix potential tipc_node refcnt leak in tipc_rcv

2020-04-18T20:24:20Z

tipc_rcv() invokes tipc_node_find() twice, which returns a reference of the specified tipc_node object to "n" with increased refcnt. When tipc_rcv() returns or a new object is assigned to "n", the original local reference of "n" becomes invalid, so the refcount should be decreased to keep refcount balanced. The issue happens in some paths of tipc_rcv(), which forget to decrease the refcnt increased by tipc_node_find() and will cause a refcnt leak. Fix this issue by calling tipc_node_put() before the original object pointed by "n" becomes invalid. Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Signed-off-by: David S. Miller

tipc: Add a missing case of TIPC_DIRECT_MSG type

2020-03-26T18:21:02Z

In the commit f73b12812a3d ("tipc: improve throughput between nodes in netns"), we're missing a check to handle TIPC_DIRECT_MSG type, it's still using old sending mechanism for this message type. So, throughput improvement is not significant as expected. Besides that, when sending a large message with that type, we're also handle wrong receiving queue, it should be enqueued in socket receiving instead of multicast messages. Fix this by adding the missing case for TIPC_DIRECT_MSG. Fixes: f73b12812a3d ("tipc: improve throughput between nodes in netns") Reported-by: Tuong Lien Signed-off-by: Hoang Le Acked-by: Jon Maloy Signed-off-by: David S. Miller

tipc: make three functions static

2020-02-10T09:23:00Z

Fix the following sparse warning: net/tipc/node.c:281:6: warning: symbol 'tipc_node_free' was not declared. Should it be static? net/tipc/node.c:2801:5: warning: symbol '__tipc_nl_node_set_key' was not declared. Should it be static? net/tipc/node.c:2878:5: warning: symbol '__tipc_nl_node_flush_key' was not declared. Should it be static? Fixes: fc1b6d6de220 ("tipc: introduce TIPC encryption & authentication") Fixes: e1f32190cf7d ("tipc: add support for AEAD key setting via netlink") Signed-off-by: Chen Wandun Signed-off-by: David S. Miller

tipc: introduce variable window congestion control

2019-12-11T01:31:15Z

We introduce a simple variable window congestion control for links. The algorithm is inspired by the Reno algorithm, covering both 'slow start', 'congestion avoidance', and 'fast recovery' modes. - We introduce hard lower and upper window limits per link, still different and configurable per bearer type. - We introduce a 'slow start theshold' variable, initially set to the maximum window size. - We let a link start at the minimum congestion window, i.e. in slow start mode, and then let is grow rapidly (+1 per rceived ACK) until it reaches the slow start threshold and enters congestion avoidance mode. - In congestion avoidance mode we increment the congestion window for each window-size number of acked packets, up to a possible maximum equal to the configured maximum window. - For each non-duplicate NACK received, we drop back to fast recovery mode, by setting the both the slow start threshold to and the congestion window to (current_congestion_window / 2). - If the timeout handler finds that the transmit queue has not moved since the previous timeout, it drops the link back to slow start and forces a probe containing the last sent sequence number to the sent to the peer, so that this can discover the stale situation. This change does in reality have effect only on unicast ethernet transport, as we have seen that there is no room whatsoever for increasing the window max size for the UDP bearer. For now, we also choose to keep the limits for the broadcast link unchanged and equal. This algorithm seems to give a 50-100% throughput improvement for messages larger than MTU. Suggested-by: Xin Long Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: update replicast capability for broadcast send link

2019-11-22T17:29:50Z

When setting up a cluster with non-replicast/replicast capability supported. This capability will be disabled for broadcast send link in order to be backwards compatible. However, when these non-support nodes left and be removed out the cluster. We don't update this capability on broadcast send link. Then, some of features that based on this capability will also disabling as unexpected. In this commit, we make sure the broadcast send link capabilities will be re-calculated as soon as a node removed/rejoined a cluster. Acked-by: Jon Maloy Signed-off-by: Hoang Le Signed-off-by: David S. Miller

tipc: add support for AEAD key setting via netlink

2019-11-08T22:01:59Z

This commit adds two netlink commands to TIPC in order for user to be able to set or remove AEAD keys: - TIPC_NL_KEY_SET - TIPC_NL_KEY_FLUSH When the 'KEY_SET' is given along with the key data, the key will be initiated and attached to TIPC crypto. On the other hand, the 'KEY_FLUSH' command will remove all existing keys if any. Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: introduce TIPC encryption & authentication

2019-11-08T22:01:59Z

This commit offers an option to encrypt and authenticate all messaging, including the neighbor discovery messages. The currently most advanced algorithm supported is the AEAD AES-GCM (like IPSec or TLS). All encryption/decryption is done at the bearer layer, just before leaving or after entering TIPC. Supported features: - Encryption & authentication of all TIPC messages (header + data); - Two symmetric-key modes: Cluster and Per-node; - Automatic key switching; - Key-expired revoking (sequence number wrapped); - Lock-free encryption/decryption (RCU); - Asynchronous crypto, Intel AES-NI supported; - Multiple cipher transforms; - Logs & statistics; Two key modes: - Cluster key mode: One single key is used for both TX & RX in all nodes in the cluster. - Per-node key mode: Each nodes in the cluster has one specific TX key. For RX, a node requires its peers' TX key to be able to decrypt the messages from those peers. Key setting from user-space is performed via netlink by a user program (e.g. the iproute2 'tipc' tool). Internal key state machine: Attach Align(RX) +-+ +-+ | V | V +---------+ Attach +---------+ | IDLE |---------------->| PENDING |(user = 0) +---------+ +---------+ A A Switch| A | | | | | | Free(switch/revoked) | | (Free)| +----------------------+ | |Timeout | (TX) | | |(RX) | | | | | | v | +---------+ Switch +---------+ | PASSIVE |<----------------| ACTIVE | +---------+ (RX) +---------+ (user = 1) (user >= 1) The number of TFMs is 10 by default and can be changed via the procfs 'net/tipc/max_tfms'. At this moment, as for simplicity, this file is also used to print the crypto statistics at runtime: echo 0xfff1 > /proc/sys/net/tipc/max_tfms The patch defines a new TIPC version (v7) for the encryption message (- backward compatibility as well). The message is basically encapsulated as follows: +----------------------------------------------------------+ | TIPCv7 encryption | Original TIPCv2 | Authentication | | header | packet (encrypted) | Tag | +----------------------------------------------------------+ The throughput is about ~40% for small messages (compared with non- encryption) and ~9% for large messages. With the support from hardware crypto i.e. the Intel AES-NI CPU instructions, the throughput increases upto ~85% for small messages and ~55% for large messages. By default, the new feature is inactive (i.e. no encryption) until user sets a key for TIPC. There is however also a new option - "TIPC_CRYPTO" in the kernel configuration to enable/disable the new code when needed. MAINTAINERS | add two new files 'crypto.h' & 'crypto.c' in tipc Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: enable creating a "preliminary" node

2019-11-08T22:01:59Z

When user sets RX key for a peer not existing on the own node, a new node entry is needed to which the RX key will be attached. However, since the peer node address (& capabilities) is unknown at that moment, only the node-ID is provided, this commit allows the creation of a node with only the data that we call as “preliminary”. A preliminary node is not the object of the “tipc_node_find()” but the “tipc_node_find_by_id()”. Once the first message i.e. LINK_CONFIG comes from that peer, and is successfully decrypted by the own node, the actual peer node data will be properly updated and the node will function as usual. In addition, the node timer always starts when a node object is created so if a preliminary node is not used, it will be cleaned up. The later encryption functions will also use the node timer and be able to create a preliminary node automatically when needed. Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: eliminate checking netns if node established

2019-11-08T04:08:53Z

Currently, we scan over all network namespaces at each received discovery message in order to check if the sending peer might be present in a host local namespaces. This is unnecessary since we can assume that a peer will not change its location during an established session. We now improve the condition for this testing so that we don't perform any redundant scans. Fixes: f73b12812a3d ("tipc: improve throughput between nodes in netns") Acked-by: Jon Maloy Signed-off-by: Hoang Le Signed-off-by: David S. Miller

tipc: update cluster capabilities if node deleted

2019-11-07T01:37:43Z

There are two improvements when re-calculate cluster capabilities: - When deleting a specific down node, need to re-calculate. - In tipc_node_cleanup(), do not need to re-calculate if node is still existing in cluster. Acked-by: Jon Maloy Signed-off-by: Hoang Le Acked-by: Jon Signed-off-by: David S. Miller