summaryrefslogtreecommitdiffstats
path: root/certs/system_keyring.c
Commit message (Collapse)AuthorAgeFilesLines
* certs: Reference revocation list for all keyringsEric Snowberg2023-08-171-6/+6
| | | | | | | | | | | | | | | | | | Systems booted with shim have a Forbidden Signature Database called mokx. During boot, hashes and certs contained within the mokx are loaded into the blacklist keyring. When calling verify_pkcs7_message_sig the contents of the blacklist keyring (or revocation list) are referenced when validating keys on the platform keyring. Currently, when validating against the secondary or builtin keyrings, the revocation list is not referenced. Move up the check to allow the revocation list to be used with all keyrings, including the secondary and builtin, allowing the system owner to take corrective action should a vulnerability be found within keys contained within either keyring. Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
* integrity: PowerVM support for loading third party code signing keysNayna Jain2023-08-171-0/+30
| | | | | | | | | | | | | | | On secure boot enabled PowerVM LPAR, third party code signing keys are needed during early boot to verify signed third party modules. These third party keys are stored in moduledb object in the Platform KeyStore (PKS). Load third party code signing keys onto .secondary_trusted_keys keyring. Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Reviewed-and-tested-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Nageswara R Sastry <rnsastry@linux.ibm.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
* KEYS: DigitalSignature link restrictionEric Snowberg2023-08-171-0/+49
| | | | | | | | | | | | | | Add a new link restriction. Restrict the addition of keys in a keyring based on the key having digitalSignature usage set. Additionally, verify the new certificate against the ones in the system keyrings. Add two additional functions to use the new restriction within either the builtin or secondary keyrings. [jarkko@kernel.org: Fix checkpatch.pl --strict issues] Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Reviewed-and-tested-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
* KEYS: Add missing function documentationEric Snowberg2023-04-241-3/+11
| | | | | | | | | | | | | | | | | | | | | | Compiling with 'W=1' results in warnings that 'Function parameter or member not described' Add the missing parameters for restrict_link_by_builtin_and_secondary_trusted and restrict_link_to_builtin_trusted. Use /* instead of /** for get_builtin_and_secondary_restriction, since it is a static function. Fix wrong function name restrict_link_to_builtin_trusted. Fixes: d3bfe84129f6 ("certs: Add a secondary system keyring that can be added to dynamically") Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Reviewed-by: Petr Vorel <pvorel@suse.cz> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
* certs: Move load_certificate_list() to be with the asymmetric keys codeDavid Howells2022-06-211-3/+3
| | | | | | | | | | | | | | | | Move load_certificate_list(), which loads a series of binary X.509 certificates from a blob and inserts them as keys into a keyring, to be with the asymmetric keys code that it drives. This makes it easier to add FIPS selftest code in which we need to load up a private keyring for the tests to use. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Simo Sorce <simo@redhat.com> Reviewed-by: Herbert Xu <herbert@gondor.apana.org.au> cc: keyrings@vger.kernel.org cc: linux-crypto@vger.kernel.org Link: https://lore.kernel.org/r/165515742145.1554877.13488098107542537203.stgit@warthog.procyon.org.uk/
* KEYS: Introduce link restriction for machine keysEric Snowberg2022-03-081-1/+34
| | | | | | | | | | | | | | | | | | | | | | Introduce a new link restriction that includes the trusted builtin, secondary and machine keys. The restriction is based on the key to be added being vouched for by a key in any of these three keyrings. With the introduction of the machine keyring, the end-user may choose to trust Machine Owner Keys (MOK) within the kernel. If they have chosen to trust them, the .machine keyring will contain these keys. If not, the machine keyring will always be empty. Update the restriction check to allow the secondary trusted keyring to also trust machine keys. Allow the .machine keyring to be linked to the secondary_trusted_keys. After the link is created, keys contained in the .machine keyring will automatically be searched when searching secondary_trusted_keys. Suggested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
* KEYS: store reference to machine keyringEric Snowberg2022-03-081-0/+9
| | | | | | | | | | | | Expose the .machine keyring created in integrity code by adding a reference. Store a reference to the machine keyring in system keyring code. The system keyring code needs this to complete the keyring link to the machine keyring. Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
* Merge tag 'integrity-v5.13' of ↵Linus Torvalds2021-05-011-2/+23
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull IMA updates from Mimi Zohar: "In addition to loading the kernel module signing key onto the builtin keyring, load it onto the IMA keyring as well. Also six trivial changes and bug fixes" * tag 'integrity-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: ima: ensure IMA_APPRAISE_MODSIG has necessary dependencies ima: Fix fall-through warnings for Clang integrity: Add declarations to init_once void arguments. ima: Fix function name error in comment. ima: enable loading of build time generated key on .ima keyring ima: enable signing of modules with build time generated key keys: cleanup build time module signing keys ima: Fix the error code for restoring the PCR value ima: without an IMA policy loaded, return quickly
| * ima: enable loading of build time generated key on .ima keyringNayna Jain2021-04-091-10/+40
| | | | | | | | | | | | | | | | | | | | The kernel currently only loads the kernel module signing key onto the builtin trusted keyring. Load the module signing key onto the IMA keyring as well. Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Acked-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* | certs: Move load_system_certificate_list to a common functionEric Snowberg2021-03-111-46/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move functionality within load_system_certificate_list to a common function, so it can be reused in the future. DH Changes: - Added inclusion of common.h to common.c (Eric [1]). Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: David Howells <dhowells@redhat.com> cc: keyrings@vger.kernel.org Link: https://lore.kernel.org/r/EDA280F9-F72D-4181-93C7-CDBE95976FF7@oracle.com/ [1] Link: https://lore.kernel.org/r/20200930201508.35113-2-eric.snowberg@oracle.com/ Link: https://lore.kernel.org/r/20210122181054.32635-3-eric.snowberg@oracle.com/ # v5 Link: https://lore.kernel.org/r/161428672825.677100.7545516389752262918.stgit@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/161433311696.902181.3599366124784670368.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/161529605850.163428.7786675680201528556.stgit@warthog.procyon.org.uk/ # v3
* | certs: Add EFI_CERT_X509_GUID support for dbx entriesEric Snowberg2021-03-111-0/+6
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes CVE-2020-26541. The Secure Boot Forbidden Signature Database, dbx, contains a list of now revoked signatures and keys previously approved to boot with UEFI Secure Boot enabled. The dbx is capable of containing any number of EFI_CERT_X509_SHA256_GUID, EFI_CERT_SHA256_GUID, and EFI_CERT_X509_GUID entries. Currently when EFI_CERT_X509_GUID are contained in the dbx, the entries are skipped. Add support for EFI_CERT_X509_GUID dbx entries. When a EFI_CERT_X509_GUID is found, it is added as an asymmetrical key to the .blacklist keyring. Anytime the .platform keyring is used, the keys in the .blacklist keyring are referenced, if a matching key is found, the key will be rejected. [DH: Made the following changes: - Added to have a config option to enable the facility. This allows a Kconfig solution to make sure that pkcs7_validate_trust() is enabled.[1][2] - Moved the functions out from the middle of the blacklist functions. - Added kerneldoc comments.] Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> cc: Randy Dunlap <rdunlap@infradead.org> cc: Mickaël Salaün <mic@digikod.net> cc: Arnd Bergmann <arnd@kernel.org> cc: keyrings@vger.kernel.org Link: https://lore.kernel.org/r/20200901165143.10295-1-eric.snowberg@oracle.com/ # rfc Link: https://lore.kernel.org/r/20200909172736.73003-1-eric.snowberg@oracle.com/ # v2 Link: https://lore.kernel.org/r/20200911182230.62266-1-eric.snowberg@oracle.com/ # v3 Link: https://lore.kernel.org/r/20200916004927.64276-1-eric.snowberg@oracle.com/ # v4 Link: https://lore.kernel.org/r/20210122181054.32635-2-eric.snowberg@oracle.com/ # v5 Link: https://lore.kernel.org/r/161428672051.677100.11064981943343605138.stgit@warthog.procyon.org.uk/ Link: https://lore.kernel.org/r/161433310942.902181.4901864302675874242.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/161529605075.163428.14625520893961300757.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/bc2c24e3-ed68-2521-0bf4-a1f6be4a895d@infradead.org/ [1] Link: https://lore.kernel.org/r/20210225125638.1841436-1-arnd@kernel.org/ [2]
* certs: Replace K{U,G}IDT_INIT() with GLOBAL_ROOT_{U,G}IDMickaël Salaün2021-01-211-2/+3
| | | | | | | | Align with the new macros and add appropriate include files. Signed-off-by: Mickaël Salaün <mic@linux.microsoft.com> Signed-off-by: David Howells <dhowells@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org>
* PKCS#7: Refactor verify_pkcs7_signature()Thiago Jung Bauermann2019-08-051-16/+45
| | | | | | | | | | | | | | | IMA will need to verify a PKCS#7 signature which has already been parsed. For this reason, factor out the code which does that from verify_pkcs7_signature() into a new function which takes a struct pkcs7_message instead of a data buffer. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Cc: David Howells <dhowells@redhat.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* Revert "Merge tag 'keys-acl-20190703' of ↵Linus Torvalds2019-07-101-3/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs" 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 <ebiggers@kernel.org> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'keys-acl-20190703' of ↵Linus Torvalds2019-07-081-9/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs 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
| * keys: Replace uid/gid/perm permissions checking with an ACLDavid Howells2019-06-271-9/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the uid/gid/perm permissions checking on a key with an ACL to allow the SETATTR and SEARCH permissions to be split. This will also allow a greater range of subjects to represented. ============ WHY DO THIS? ============ The problem is that SETATTR and SEARCH cover a slew of actions, not all of which should be grouped together. For SETATTR, this includes actions that are about controlling access to a key: (1) Changing a key's ownership. (2) Changing a key's security information. (3) Setting a keyring's restriction. And actions that are about managing a key's lifetime: (4) Setting an expiry time. (5) Revoking a key. and (proposed) managing a key as part of a cache: (6) Invalidating a key. Managing a key's lifetime doesn't really have anything to do with controlling access to that key. Expiry time is awkward since it's more about the lifetime of the content and so, in some ways goes better with WRITE permission. It can, however, be set unconditionally by a process with an appropriate authorisation token for instantiating a key, and can also be set by the key type driver when a key is instantiated, so lumping it with the access-controlling actions is probably okay. As for SEARCH permission, that currently covers: (1) Finding keys in a keyring tree during a search. (2) Permitting keyrings to be joined. (3) Invalidation. But these don't really belong together either, since these actions really need to be controlled separately. Finally, there are number of special cases to do with granting the administrator special rights to invalidate or clear keys that I would like to handle with the ACL rather than key flags and special checks. =============== WHAT IS CHANGED =============== The SETATTR permission is split to create two new permissions: (1) SET_SECURITY - which allows the key's owner, group and ACL to be changed and a restriction to be placed on a keyring. (2) REVOKE - which allows a key to be revoked. The SEARCH permission is split to create: (1) SEARCH - which allows a keyring to be search and a key to be found. (2) JOIN - which allows a keyring to be joined as a session keyring. (3) INVAL - which allows a key to be invalidated. The WRITE permission is also split to create: (1) WRITE - which allows a key's content to be altered and links to be added, removed and replaced in a keyring. (2) CLEAR - which allows a keyring to be cleared completely. This is split out to make it possible to give just this to an administrator. (3) REVOKE - see above. Keys acquire ACLs which consist of a series of ACEs, and all that apply are unioned together. An ACE specifies a subject, such as: (*) Possessor - permitted to anyone who 'possesses' a key (*) Owner - permitted to the key owner (*) Group - permitted to the key group (*) Everyone - permitted to everyone Note that 'Other' has been replaced with 'Everyone' on the assumption that you wouldn't grant a permit to 'Other' that you wouldn't also grant to everyone else. Further subjects may be made available by later patches. The ACE also specifies a permissions mask. The set of permissions is now: VIEW Can view the key metadata READ Can read the key content WRITE Can update/modify the key content SEARCH Can find the key by searching/requesting LINK Can make a link to the key SET_SECURITY Can change owner, ACL, expiry INVAL Can invalidate REVOKE Can revoke JOIN Can join this keyring CLEAR Can clear this keyring The KEYCTL_SETPERM function is then deprecated. The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set, or if the caller has a valid instantiation auth token. The KEYCTL_INVALIDATE function then requires INVAL. The KEYCTL_REVOKE function then requires REVOKE. The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an existing keyring. The JOIN permission is enabled by default for session keyrings and manually created keyrings only. ====================== BACKWARD COMPATIBILITY ====================== To maintain backward compatibility, KEYCTL_SETPERM will translate the permissions mask it is given into a new ACL for a key - unless KEYCTL_SET_ACL has been called on that key, in which case an error will be returned. It will convert possessor, owner, group and other permissions into separate ACEs, if each portion of the mask is non-zero. SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY. WRITE permission turns on WRITE, REVOKE and, if a keyring, CLEAR. JOIN is turned on if a keyring is being altered. The KEYCTL_DESCRIBE function translates the ACL back into a permissions mask to return depending on possessor, owner, group and everyone ACEs. It will make the following mappings: (1) INVAL, JOIN -> SEARCH (2) SET_SECURITY -> SETATTR (3) REVOKE -> WRITE if SETATTR isn't already set (4) CLEAR -> WRITE Note that the value subsequently returned by KEYCTL_DESCRIBE may not match the value set with KEYCTL_SETATTR. ======= TESTING ======= This passes the keyutils testsuite for all but a couple of tests: (1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed if the type doesn't have ->read(). You still can't actually read the key. (2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't work as Other has been replaced with Everyone in the ACL. Signed-off-by: David Howells <dhowells@redhat.com>
* | treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 36Thomas Gleixner2019-05-241-5/+1
|/ | | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public licence as published by the free software foundation either version 2 of the licence or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 114 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520170857.552531963@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* kexec, KEYS: Make use of platform keyring for signature verifyKairui Song2019-02-041-1/+12
| | | | | | | | | | | | | | | | | | | | | This patch allows the kexec_file_load syscall to verify the PE signed kernel image signature based on the preboot keys stored in the .platform keyring, as fall back, if the signature verification failed due to not finding the public key in the secondary or builtin keyrings. This commit adds a VERIFY_USE_PLATFORM_KEYRING similar to previous VERIFY_USE_SECONDARY_KEYRING indicating that verify_pkcs7_signature should verify the signature using platform keyring. Also, decrease the error message log level when verification failed with -ENOKEY, so that if called tried multiple time with different keyring it won't generate extra noises. Signed-off-by: Kairui Song <kasong@redhat.com> Cc: David Howells <dhowells@redhat.com> Acked-by: Dave Young <dyoung@redhat.com> (for kexec_file_load part) [zohar@linux.ibm.com: tweaked the first paragraph of the patch description, and fixed checkpatch warning.] Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* integrity, KEYS: add a reference to platform keyringKairui Song2019-02-041-0/+10
| | | | | | | | | | | | | | | | | commit 9dc92c45177a ("integrity: Define a trusted platform keyring") introduced a .platform keyring for storing preboot keys, used for verifying kernel image signatures. Currently only IMA-appraisal is able to use the keyring to verify kernel images that have their signature stored in xattr. This patch exposes the .platform keyring, making it accessible for verifying PE signed kernel images as well. Suggested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Kairui Song <kasong@redhat.com> Cc: David Howells <dhowells@redhat.com> [zohar@linux.ibm.com: fixed checkpatch errors, squashed with patch fix] Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* Replace magic for trusting the secondary keyring with #defineYannik Sembritzki2018-08-161-1/+2
| | | | | | | | | | | Replace the use of a magic number that indicates that verify_*_signature() should use the secondary keyring with a symbol. Signed-off-by: Yannik Sembritzki <yannik@sembritzki.me> Signed-off-by: David Howells <dhowells@redhat.com> Cc: keyrings@vger.kernel.org Cc: linux-security-module@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* KEYS: Use structure to capture key restriction function and dataMat Martineau2017-04-041-1/+20
| | | | | | | | | | | | | | Replace struct key's restrict_link function pointer with a pointer to the new struct key_restriction. The structure contains pointers to the restriction function as well as relevant data for evaluating the restriction. The garbage collector checks restrict_link->keytype when key types are unregistered. Restrictions involving a removed key type are converted to use restrict_link_reject so that restrictions cannot be removed by unregistering key types. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
* KEYS: Split role of the keyring pointer for keyring restrict functionsMat Martineau2017-04-031-7/+11
| | | | | | | | | | | | | | The first argument to the restrict_link_func_t functions was a keyring pointer. These functions are called by the key subsystem with this argument set to the destination keyring, but restrict_link_by_signature expects a pointer to the relevant trusted keyring. Restrict functions may need something other than a single struct key pointer to allow or reject key linkage, so the data used to make that decision (such as the trust keyring) is moved to a new, fourth argument. The first argument is now always the destination keyring. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
* certs: Add a secondary system keyring that can be added to dynamicallyDavid Howells2016-04-111-16/+71
| | | | | | | | | | | | | | | | | Add a secondary system keyring that can be added to by root whilst the system is running - provided the key being added is vouched for by a key built into the kernel or already added to the secondary keyring. Rename .system_keyring to .builtin_trusted_keys to distinguish it more obviously from the new keyring (called .secondary_trusted_keys). The new keyring needs to be enabled with CONFIG_SECONDARY_TRUSTED_KEYRING. If the secondary keyring is enabled, a link is created from that to .builtin_trusted_keys so that the the latter will automatically be searched too if the secondary keyring is searched. Signed-off-by: David Howells <dhowells@redhat.com>
* KEYS: Remove KEY_FLAG_TRUSTED and KEY_ALLOC_TRUSTEDDavid Howells2016-04-111-2/+0
| | | | | | | | | | | | Remove KEY_FLAG_TRUSTED and KEY_ALLOC_TRUSTED as they're no longer meaningful. Also we can drop the trusted flag from the preparse structure. Given this, we no longer need to pass the key flags through to restrict_link(). Further, we can now get rid of keyring_restrict_trusted_only() also. Signed-off-by: David Howells <dhowells@redhat.com>
* KEYS: Move the point of trust determination to __key_link()David Howells2016-04-111-3/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move the point at which a key is determined to be trustworthy to __key_link() so that we use the contents of the keyring being linked in to to determine whether the key being linked in is trusted or not. What is 'trusted' then becomes a matter of what's in the keyring. Currently, the test is done when the key is parsed, but given that at that point we can only sensibly refer to the contents of the system trusted keyring, we can only use that as the basis for working out the trustworthiness of a new key. With this change, a trusted keyring is a set of keys that once the trusted-only flag is set cannot be added to except by verification through one of the contained keys. Further, adding a key into a trusted keyring, whilst it might grant trustworthiness in the context of that keyring, does not automatically grant trustworthiness in the context of a second keyring to which it could be secondarily linked. To accomplish this, the authentication data associated with the key source must now be retained. For an X.509 cert, this means the contents of the AuthorityKeyIdentifier and the signature data. If system keyrings are disabled then restrict_link_by_builtin_trusted() resolves to restrict_link_reject(). The integrity digital signature code still works correctly with this as it was previously using KEY_FLAG_TRUSTED_ONLY, which doesn't permit anything to be added if there is no system keyring against which trust can be determined. Signed-off-by: David Howells <dhowells@redhat.com>
* KEYS: Add a facility to restrict new links into a keyringDavid Howells2016-04-111-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a facility whereby proposed new links to be added to a keyring can be vetted, permitting them to be rejected if necessary. This can be used to block public keys from which the signature cannot be verified or for which the signature verification fails. It could also be used to provide blacklisting. This affects operations like add_key(), KEYCTL_LINK and KEYCTL_INSTANTIATE. To this end: (1) A function pointer is added to the key struct that, if set, points to the vetting function. This is called as: int (*restrict_link)(struct key *keyring, const struct key_type *key_type, unsigned long key_flags, const union key_payload *key_payload), where 'keyring' will be the keyring being added to, key_type and key_payload will describe the key being added and key_flags[*] can be AND'ed with KEY_FLAG_TRUSTED. [*] This parameter will be removed in a later patch when KEY_FLAG_TRUSTED is removed. The function should return 0 to allow the link to take place or an error (typically -ENOKEY, -ENOPKG or -EKEYREJECTED) to reject the link. The pointer should not be set directly, but rather should be set through keyring_alloc(). Note that if called during add_key(), preparse is called before this method, but a key isn't actually allocated until after this function is called. (2) KEY_ALLOC_BYPASS_RESTRICTION is added. This can be passed to key_create_or_update() or key_instantiate_and_link() to bypass the restriction check. (3) KEY_FLAG_TRUSTED_ONLY is removed. The entire contents of a keyring with this restriction emplaced can be considered 'trustworthy' by virtue of being in the keyring when that keyring is consulted. (4) key_alloc() and keyring_alloc() take an extra argument that will be used to set restrict_link in the new key. This ensures that the pointer is set before the key is published, thus preventing a window of unrestrictedness. Normally this argument will be NULL. (5) As a temporary affair, keyring_restrict_trusted_only() is added. It should be passed to keyring_alloc() as the extra argument instead of setting KEY_FLAG_TRUSTED_ONLY on a keyring. This will be replaced in a later patch with functions that look in the appropriate places for authoritative keys. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* PKCS#7: Make trust determination dependent on contents of trust keyringDavid Howells2016-04-061-9/+4
| | | | | | | | | | | Make the determination of the trustworthiness of a key dependent on whether a key that can verify it is present in the supplied ring of trusted keys rather than whether or not the verifying key has KEY_FLAG_TRUSTED set. verify_pkcs7_signature() will return -ENOKEY if the PKCS#7 message trust chain cannot be verified. Signed-off-by: David Howells <dhowells@redhat.com>
* KEYS: Generalise system_verify_data() to provide access to internal contentDavid Howells2016-04-061-10/+35
| | | | | | | | | | | | | | | Generalise system_verify_data() to provide access to internal content through a callback. This allows all the PKCS#7 stuff to be hidden inside this function and removed from the PE file parser and the PKCS#7 test key. If external content is not required, NULL should be passed as data to the function. If the callback is not required, that can be set to NULL. The function is now called verify_pkcs7_signature() to contrast with verify_pefile_signature() and the definitions of both have been moved into linux/verification.h along with the key_being_used_for enum. Signed-off-by: David Howells <dhowells@redhat.com>
* KEYS: Add an alloc flag to convey the builtinness of a keyDavid Howells2016-02-091-2/+2
| | | | | | | | Add KEY_ALLOC_BUILT_IN to convey that a key should have KEY_FLAG_BUILTIN set rather than setting it after the fact. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* Move certificate handling to its own directoryDavid Howells2015-08-141-0/+157
Move certificate handling out of the kernel/ directory and into a certs/ directory to get all the weird stuff in one place and move the generated signing keys into this directory. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: David Woodhouse <David.Woodhouse@intel.com>