kernel/linux.git/security/keys/key.c, branch v6.6.131

keys: Fix overwrite of key expiration on instantiation

2024-05-17T10:02:39+00:00

commit 9da27fb65a14c18efd4473e2e82b76b53ba60252 upstream. The expiry time of a key is unconditionally overwritten during instantiation, defaulting to turn it permanent. This causes a problem for DNS resolution as the expiration set by user-space is overwritten to TIME64_MAX, disabling further DNS updates. Fix this by restoring the condition that key_set_expiry is only called when the pre-parser sets a specific expiry. Fixes: 39299bdd2546 ("keys, dns: Allow key types (eg. DNS) to be reclaimed immediately on expiry") Signed-off-by: Silvio Gissi cc: David Howells cc: Hazem Mohamed Abuelfotoh cc: linux-afs@lists.infradead.org cc: linux-cifs@vger.kernel.org cc: keyrings@vger.kernel.org cc: netdev@vger.kernel.org cc: stable@vger.kernel.org Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen Signed-off-by: Greg Kroah-Hartman

keys, dns: Allow key types (eg. DNS) to be reclaimed immediately on expiry

2024-01-01T12:42:33+00:00

[ Upstream commit 39299bdd2546688d92ed9db4948f6219ca1b9542 ] If a key has an expiration time, then when that time passes, the key is left around for a certain amount of time before being collected (5 mins by default) so that EKEYEXPIRED can be returned instead of ENOKEY. This is a problem for DNS keys because we want to redo the DNS lookup immediately at that point. Fix this by allowing key types to be marked such that keys of that type don't have this extra period, but are reclaimed as soon as they expire and turn this on for dns_resolver-type keys. To make this easier to handle, key->expiry is changed to be permanent if TIME64_MAX rather than 0. Furthermore, give such new-style negative DNS results a 1s default expiry if no other expiry time is set rather than allowing it to stick around indefinitely. This shouldn't be zero as ls will follow a failing stat call immediately with a second with AT_SYMLINK_NOFOLLOW added. Fixes: 1a4240f4764a ("DNS: Separate out CIFS DNS Resolver code") Signed-off-by: David Howells Tested-by: Markus Suvanto cc: Wang Lei cc: Jeff Layton cc: Steve French cc: Marc Dionne cc: Jarkko Sakkinen cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: linux-afs@lists.infradead.org cc: linux-cifs@vger.kernel.org cc: linux-nfs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: keyrings@vger.kernel.org cc: netdev@vger.kernel.org Signed-off-by: Sasha Levin

KEYS: Add new function key_create()

2023-02-13T08:11:20+00:00

key_create() works like key_create_or_update() but does not allow updating an existing key, instead returning ERR_PTR(-EEXIST). key_create() will be used by the blacklist keyring which should not create duplicate entries or update existing entries. Instead a dedicated message with appropriate severity will be logged. Signed-off-by: Thomas Weißschuh Signed-off-by: Jarkko Sakkinen

certs: Fix blacklist flag type confusion

2021-01-21T16:16:10+00:00

KEY_FLAG_KEEP is not meant to be passed to keyring_alloc() or key_alloc(), as these only take KEY_ALLOC_* flags. KEY_FLAG_KEEP has the same value as KEY_ALLOC_BYPASS_RESTRICTION, but fortunately only key_create_or_update() uses it. LSMs using the key_alloc hook don't check that flag. KEY_FLAG_KEEP is then ignored but fortunately (again) the root user cannot write to the blacklist keyring, so it is not possible to remove a key/hash from it. Fix this by adding a KEY_ALLOC_SET_KEEP flag that tells key_alloc() to set KEY_FLAG_KEEP on the new key. blacklist_init() can then, correctly, pass this to keyring_alloc(). We can also use this in ima_mok_init() rather than setting the flag manually. Note that this doesn't fix an observable bug with the current implementation but it is required to allow addition of new hashes to the blacklist in the future without making it possible for them to be removed. Fixes: 734114f8782f ("KEYS: Add a system blacklist keyring") Reported-by: Mickaël Salaün Signed-off-by: David Howells cc: Mickaël Salaün cc: Mimi Zohar Cc: David Woodhouse

keys: Provide the original description to the key preparser

2020-11-23T18:09:29+00:00

Provide the proposed description (add key) or the original description (update/instantiate key) when preparsing a key so that the key type can validate it against the data. This is important for rxrpc server keys as we need to check that they have the right amount of key material present - and it's better to do that when the key is loaded rather than deep in trying to process a response packet. Signed-off-by: David Howells cc: Jarkko Sakkinen cc: keyrings@vger.kernel.org

watch_queue: Add a key/keyring notification facility

2020-05-19T14:19:06+00:00

Add a key/keyring change notification facility whereby notifications about changes in key and keyring content and attributes can be received. Firstly, an event queue needs to be created: pipe2(fds, O_NOTIFICATION_PIPE); ioctl(fds[1], IOC_WATCH_QUEUE_SET_SIZE, 256); then a notification can be set up to report notifications via that queue: struct watch_notification_filter filter = { .nr_filters = 1, .filters = { [0] = { .type = WATCH_TYPE_KEY_NOTIFY, .subtype_filter[0] = UINT_MAX, }, }, }; ioctl(fds[1], IOC_WATCH_QUEUE_SET_FILTER, &filter); keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fds[1], 0x01); After that, records will be placed into the queue when events occur in which keys are changed in some way. Records are of the following format: struct key_notification { struct watch_notification watch; __u32 key_id; __u32 aux; } *n; Where: n->watch.type will be WATCH_TYPE_KEY_NOTIFY. n->watch.subtype will indicate the type of event, such as NOTIFY_KEY_REVOKED. n->watch.info & WATCH_INFO_LENGTH will indicate the length of the record. n->watch.info & WATCH_INFO_ID will be the second argument to keyctl_watch_key(), shifted. n->key will be the ID of the affected key. n->aux will hold subtype-dependent information, such as the key being linked into the keyring specified by n->key in the case of NOTIFY_KEY_LINKED. Note that it is permissible for event records to be of variable length - or, at least, the length may be dependent on the subtype. Note also that the queue can be shared between multiple notifications of various types. Signed-off-by: David Howells Reviewed-by: James Morris

KEYS: reaching the keys quotas correctly

2020-03-15T18:59:50+00:00

Currently, when we add a new user key, the calltrace as below: add_key() key_create_or_update() key_alloc() __key_instantiate_and_link generic_key_instantiate key_payload_reserve ...... Since commit a08bf91ce28e ("KEYS: allow reaching the keys quotas exactly"), we can reach max bytes/keys in key_alloc, but we forget to remove this limit when we reserver space for payload in key_payload_reserve. So we can only reach max keys but not max bytes when having delta between plen and type->def_datalen. Remove this limit when instantiating the key, so we can keep consistent with key_alloc. Also, fix the similar problem in keyctl_chown_key(). Fixes: 0b77f5bfb45c ("keys: make the keyring quotas controllable through /proc/sys") Fixes: a08bf91ce28e ("KEYS: allow reaching the keys quotas exactly") Cc: stable@vger.kernel.org # 5.0.x Cc: Eric Biggers Signed-off-by: Yang Xu Reviewed-by: Jarkko Sakkinen Reviewed-by: Eric Biggers Signed-off-by: Jarkko Sakkinen

KEYS: Call the IMA hook to measure keys

2019-12-12T13:53:50+00:00

Call the IMA hook from key_create_or_update() function to measure the payload when a new key is created or an existing key is updated. This patch adds the call to the IMA hook from key_create_or_update() function to measure the key on key create or update. Signed-off-by: Lakshmi Ramasubramanian Cc: David Howells Cc: Jarkko Sakkinen Signed-off-by: Mimi Zohar

Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs"

2019-07-11T01:43:43+00:00

This reverts merge 0f75ef6a9cff49ff612f7ce0578bced9d0b38325 (and thus effectively commits 7a1ade847596 ("keys: Provide KEYCTL_GRANT_PERMISSION") 2e12256b9a76 ("keys: Replace uid/gid/perm permissions checking with an ACL") that the merge brought in). It turns out that it breaks booting with an encrypted volume, and Eric biggers reports that it also breaks the fscrypt tests [1] and loading of in-kernel X.509 certificates [2]. The root cause of all the breakage is likely the same, but David Howells is off email so rather than try to work it out it's getting reverted in order to not impact the rest of the merge window. [1] https://lore.kernel.org/lkml/20190710011559.GA7973@sol.localdomain/ [2] https://lore.kernel.org/lkml/20190710013225.GB7973@sol.localdomain/ Link: https://lore.kernel.org/lkml/CAHk-=wjxoeMJfeBahnWH=9zShKp2bsVy527vo3_y8HfOdhwAAw@mail.gmail.com/ Reported-by: Eric Biggers Cc: David Howells Cc: James Morris Signed-off-by: Linus Torvalds

Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

2019-07-09T02:56:57+00:00

Pull keyring ACL support from David Howells: "This changes the permissions model used by keys and keyrings to be based on an internal ACL by the following means: - Replace the permissions mask internally with an ACL that contains a list of ACEs, each with a specific subject with a permissions mask. Potted default ACLs are available for new keys and keyrings. ACE subjects can be macroised to indicate the UID and GID specified on the key (which remain). Future commits will be able to add additional subject types, such as specific UIDs or domain tags/namespaces. Also split a number of permissions to give finer control. Examples include splitting the revocation permit from the change-attributes permit, thereby allowing someone to be granted permission to revoke a key without allowing them to change the owner; also the ability to join a keyring is split from the ability to link to it, thereby stopping a process accessing a keyring by joining it and thus acquiring use of possessor permits. - Provide a keyctl to allow the granting or denial of one or more permits to a specific subject. Direct access to the ACL is not granted, and the ACL cannot be viewed" * tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: keys: Provide KEYCTL_GRANT_PERMISSION keys: Replace uid/gid/perm permissions checking with an ACL