kernel/linux.git/net/tipc/netlink.c, branch linux-6.0.y

tipc: add automatic rekeying for encryption key

2020-09-18T20:58:37+00:00

Rekeying is required for security since a key is less secure when using for a long time. Also, key will be detached when its nonce value (or seqno ...) is exhausted. We now make the rekeying process automatic and configurable by user. Basically, TIPC will at a specific interval generate a new key by using the kernel 'Random Number Generator' cipher, then attach it as the node TX key and securely distribute to others in the cluster as RX keys (- the key exchange). The automatic key switching will then take over, and make the new key active shortly. Afterwards, the traffic from this node will be encrypted with the new session key. The same can happen in peer nodes but not necessarily at the same time. For simplicity, the automatically generated key will be initiated as a per node key. It is not too hard to also support a cluster key rekeying (e.g. a given node will generate a unique cluster key and update to the others in the cluster...), but that doesn't bring much benefit, while a per-node key is even more secure. We also enable user to force a rekeying or change the rekeying interval via netlink, the new 'set key' command option: 'TIPC_NLA_NODE_REKEYING' is added for these purposes as follows: - A value >= 1 will be set as the rekeying interval (in minutes); - A value of 0 will disable the rekeying; - A value of 'TIPC_REKEYING_NOW' (~0) will force an immediate rekeying; The default rekeying interval is (60 * 24) minutes i.e. done every day. There isn't any restriction for the value but user shouldn't set it too small or too large which results in an "ineffective" rekeying (thats ok for testing though). Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: introduce encryption master key

2020-09-18T20:58:37+00:00

In addition to the supported cluster & per-node encryption keys for the en/decryption of TIPC messages, we now introduce one option for user to set a cluster key as 'master key', which is simply a symmetric key like the former but has a longer life cycle. It has two purposes: - Authentication of new member nodes in the cluster. New nodes, having no knowledge of current session keys in the cluster will still be able to join the cluster as long as they know the master key. This is because all neighbor discovery (LINK_CONFIG) messages must be encrypted with this key. - Encryption of session encryption keys during automatic exchange and update of those.This is a feature we will introduce in a later commit in this series. We insert the new key into the currently unused slot 0 in the key array and start using it immediately once the user has set it. After joining, a node only knowing the master key should be fully communicable to existing nodes in the cluster, although those nodes may have their own session keys activated (i.e. not the master one). To support this, we define a 'grace period', starting from the time a node itself reports having no RX keys, so the existing nodes will use the master key for encryption instead. The grace period can be extended but will automatically stop after e.g. 5 seconds without a new report. This is also the basis for later key exchanging feature as the new node will be impossible to decrypt anything without the support from master key. For user to set a master key, we define a new netlink flag - 'TIPC_NLA_NODE_KEY_MASTER', so it can be added to the current 'set key' netlink command to specify the setting key to be a master key. Above all, the traditional cluster/per-node key mechanism is guaranteed to work when user comes not to use this master key option. This is also compatible to legacy nodes without the feature supported. Even this master key can be updated without any interruption of cluster connectivity but is so is needed, this has to be coordinated and set by the user. Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: add support for broadcast rcv stats dumping

2020-05-26T22:16:52+00:00

This commit enables dumping the statistics of a broadcast-receiver link like the traditional 'broadcast-link' one (which is for broadcast- sender). The link dumping can be triggered via netlink (e.g. the iproute2/tipc tool) by the link flag - 'TIPC_NLA_LINK_BROADCAST' as the indicator. The name of a broadcast-receiver link of a specific peer will be in the format: 'broadcast-link:'. For example: Link Window:50 packets RX packets:7841 fragments:2408/440 bundles:0/0 TX packets:0 fragments:0/0 bundles:0/0 RX naks:0 defs:124 dups:0 TX naks:21 acks:0 retrans:0 Congestion link:0 Send queue max:0 avg:0 In addition, the broadcast-receiver link statistics can be reset in the usual way via netlink by specifying that link name in command. Note: the 'tipc_link_name_ext()' is removed because the link name can now be retrieved simply via the 'l->name'. Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: add missing attribute validation for MTU property

2020-03-03T21:28:49+00:00

Add missing attribute validation for TIPC_NLA_PROP_MTU to the netlink policy. Fixes: 901271e0403a ("tipc: implement configuration of UDP media MTU") Signed-off-by: Jakub Kicinski Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller

tipc: make legacy address flag readable over netlink

2019-12-21T05:18:42+00:00

To enable iproute2/tipc to generate backwards compatible printouts and validate command parameters for nodes using a node address, it needs to be able to read the legacy address flag from the kernel. The legacy address flag records the way in which the node identity was originally specified. The legacy address flag is requested by the netlink message TIPC_NL_ADDR_LEGACY_GET. If the flag is set the attribute TIPC_NLA_NET_ADDR_LEGACY is set in the return message. Signed-off-by: John Rutherford Acked-by: Jon Maloy Signed-off-by: David S. Miller

tipc: add support for AEAD key setting via netlink

2019-11-08T22:01:59+00:00

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

net: tipc: allocate attrs locally instead of using genl_family_attrbuf in compat_dumpit()

2019-10-06T13:44:47+00:00

As this is the last user of genl_family_attrbuf, convert to allocate attrs locally and do it in a similar way this is done in compat_doit(). Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller

net: tipc: have genetlink code to parse the attrs during dumpit

2019-10-06T13:44:47+00:00

Benefit from the fact that the generic netlink code can parse the attrs for dumpit op and avoid need to parse it in the op callback. Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller

tipc: fix missing indentation in source code

2019-06-24T14:29:45+00:00

Fix misalignment of policy statement in netlink.c due to automatic spatch code transformation. Fixes: 3b0f31f2b8c9 ("genetlink: make policy common to family") Acked-by: Jon Maloy Signed-off-by: John Rutherford Signed-off-by: David S. Miller

genetlink: optionally validate strictly/dumps

2019-04-27T21:07:22+00:00

Add options to strictly validate messages and dump messages, sometimes perhaps validating dump messages non-strictly may be required, so add an option for that as well. Since none of this can really be applied to existing commands, set the options everwhere using the following spatch: @@ identifier ops; expression X; @@ struct genl_ops ops[] = { ..., { .cmd = X, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, ... }, ... }; For new commands one should just not copy the .validate 'opt-out' flags and thus get strict validation. Signed-off-by: Johannes Berg Signed-off-by: David S. Miller