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2019-09-27Merge branch 'next-integrity' of ↵Linus Torvalds1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull integrity updates from Mimi Zohar: "The major feature in this time is IMA support for measuring and appraising appended file signatures. In addition are a couple of bug fixes and code cleanup to use struct_size(). In addition to the PE/COFF and IMA xattr signatures, the kexec kernel image may be signed with an appended signature, using the same scripts/sign-file tool that is used to sign kernel modules. Similarly, the initramfs may contain an appended signature. This contained a lot of refactoring of the existing appended signature verification code, so that IMA could retain the existing framework of calculating the file hash once, storing it in the IMA measurement list and extending the TPM, verifying the file's integrity based on a file hash or signature (eg. xattrs), and adding an audit record containing the file hash, all based on policy. (The IMA support for appended signatures patch set was posted and reviewed 11 times.) The support for appended signature paves the way for adding other signature verification methods, such as fs-verity, based on a single system-wide policy. The file hash used for verifying the signature and the signature, itself, can be included in the IMA measurement list" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: ima: ima_api: Use struct_size() in kzalloc() ima: use struct_size() in kzalloc() sefltest/ima: support appended signatures (modsig) ima: Fix use after free in ima_read_modsig() MODSIGN: make new include file self contained ima: fix freeing ongoing ahash_request ima: always return negative code for error ima: Store the measurement again when appraising a modsig ima: Define ima-modsig template ima: Collect modsig ima: Implement support for module-style appended signatures ima: Factor xattr_verify() out of ima_appraise_measurement() ima: Add modsig appraise_type option for module-style appended signatures integrity: Select CONFIG_KEYS instead of depending on it PKCS#7: Introduce pkcs7_get_digest() PKCS#7: Refactor verify_pkcs7_signature() MODSIGN: Export module signature definitions ima: initialize the "template" field with the default template
2019-09-17Merge tag 'docs-5.4' of git://git.lwn.net/linuxLinus Torvalds2-0/+56
Pull documentation updates from Jonathan Corbet: "It's a somewhat calmer cycle for docs this time, as the churn of the mass RST conversion is happily mostly behind us. - A new document on reproducible builds. - We finally got around to zapping the documentation for hardware support that was removed in 2004; one doesn't want to rush these things. - The usual assortment of fixes, typo corrections, etc" * tag 'docs-5.4' of git://git.lwn.net/linux: (67 commits) Documentation: kbuild: Add document about reproducible builds docs: printk-formats: Stop encouraging use of unnecessary %h[xudi] and %hh[xudi] Documentation: Add "earlycon=sbi" to the admin guide doc:lock: remove reference to clever use of read-write lock devices.txt: improve entry for comedi (char major 98) docs: mtd: Update spi nor reference driver doc: arm64: fix grammar dtb placed in no attributes region Documentation: sysrq: don't recommend 'S' 'U' before 'B' mailmap: Update email address for Quentin Perret docs: ftrace: clarify when tracing is disabled by the trace file docs: process: fix broken link Documentation/arm/samsung-s3c24xx: Remove stray U+FEFF character to fix title Documentation/arm/sa1100/assabet: Fix 'make assabet_defconfig' command Documentation/arm/sa1100: Remove some obsolete documentation docs/zh_CN: update Chinese howto.rst for latexdocs making Documentation: virt: Fix broken reference to virt tree's index docs: Fix typo on pull requests guide kernel-doc: Allow anonymous enum Documentation: sphinx: Don't parse socket() as identifier reference Documentation: sphinx: Add missing comma to list of strings ...
2019-09-02tpm/tpm_ftpm_tee: Document fTPM TEE driverSasha Levin2-0/+28
Documentation briefly the new fTPM driver running inside TEE. Signed-off-by: Sasha Levin <sashal@kernel.org> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2019-08-05ima: Define ima-modsig templateThiago Jung Bauermann1-0/+3
Define new "d-modsig" template field which holds the digest that is expected to match the one contained in the modsig, and also new "modsig" template field which holds the appended file signature. Add a new "ima-modsig" defined template descriptor with the new fields as well as the ones from the "ima-sig" descriptor. Change ima_store_measurement() to accept a struct modsig * argument so that it can be passed along to the templates via struct ima_event_data. Suggested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-31tpm: Document UEFI event log quirksJarkko Sakkinen2-0/+56
There are some weird quirks when it comes to UEFI event log. Provide a brief introduction to TPM event log mechanism and describe the quirks and how they can be sorted out. Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-07-15docs: security: move some books to it and updateMauro Carvalho Chehab7-3/+486
The following files belong to security: Documentation/security/LSM.rst -> Documentation/security/lsm-development.rst Documentation/lsm.txt -> Documentation/security/lsm.rst Documentation/SAK.txt -> Documentation/security/sak.rst Documentation/siphash.txt -> Documentation/security/siphash.rst Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15docs: xen-tpmfront.txt: convert it to .rstMauro Carvalho Chehab1-47/+60
In order to be able to add this file to the security book, we need first to convert it to reST. While this is not part of any book, mark it as :orphan:, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-10Revert "Merge tag 'keys-acl-20190703' of ↵Linus Torvalds2-106/+31
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>
2019-07-09Merge tag 'docs-5.3' of git://git.lwn.net/linuxLinus Torvalds2-7/+13
Pull Documentation updates from Jonathan Corbet: "It's been a relatively busy cycle for docs: - A fair pile of RST conversions, many from Mauro. These create more than the usual number of simple but annoying merge conflicts with other trees, unfortunately. He has a lot more of these waiting on the wings that, I think, will go to you directly later on. - A new document on how to use merges and rebases in kernel repos, and one on Spectre vulnerabilities. - Various improvements to the build system, including automatic markup of function() references because some people, for reasons I will never understand, were of the opinion that :c:func:``function()`` is unattractive and not fun to type. - We now recommend using sphinx 1.7, but still support back to 1.4. - Lots of smaller improvements, warning fixes, typo fixes, etc" * tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits) docs: automarkup.py: ignore exceptions when seeking for xrefs docs: Move binderfs to admin-guide Disable Sphinx SmartyPants in HTML output doc: RCU callback locks need only _bh, not necessarily _irq docs: format kernel-parameters -- as code Doc : doc-guide : Fix a typo platform: x86: get rid of a non-existent document Add the RCU docs to the core-api manual Documentation: RCU: Add TOC tree hooks Documentation: RCU: Rename txt files to rst Documentation: RCU: Convert RCU UP systems to reST Documentation: RCU: Convert RCU linked list to reST Documentation: RCU: Convert RCU basic concepts to reST docs: filesystems: Remove uneeded .rst extension on toctables scripts/sphinx-pre-install: fix out-of-tree build docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/ Documentation: PGP: update for newer HW devices Documentation: Add section about CPU vulnerabilities for Spectre Documentation: platform: Delete x86-laptop-drivers.txt docs: Note that :c:func: should no longer be used ...
2019-07-08Merge branch 'next-integrity' of ↵Linus Torvalds1-3/+4
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull integrity updates from Mimi Zohar: "Bug fixes, code clean up, and new features: - IMA policy rules can be defined in terms of LSM labels, making the IMA policy dependent on LSM policy label changes, in particular LSM label deletions. The new environment, in which IMA-appraisal is being used, frequently updates the LSM policy and permits LSM label deletions. - Prevent an mmap'ed shared file opened for write from also being mmap'ed execute. In the long term, making this and other similar changes at the VFS layer would be preferable. - The IMA per policy rule template format support is needed for a couple of new/proposed features (eg. kexec boot command line measurement, appended signatures, and VFS provided file hashes). - Other than the "boot-aggregate" record in the IMA measuremeent list, all other measurements are of file data. Measuring and storing the kexec boot command line in the IMA measurement list is the first buffer based measurement included in the measurement list" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: integrity: Introduce struct evm_xattr ima: Update MAX_TEMPLATE_NAME_LEN to fit largest reasonable definition KEXEC: Call ima_kexec_cmdline to measure the boot command line args IMA: Define a new template field buf IMA: Define a new hook to measure the kexec boot command line arguments IMA: support for per policy rule template formats integrity: Fix __integrity_init_keyring() section mismatch ima: Use designated initializers for struct ima_event_data ima: use the lsm policy update notifier LSM: switch to blocking policy update notifiers x86/ima: fix the Kconfig dependency for IMA_ARCH_POLICY ima: Make arch_policy_entry static ima: prevent a file already mmap'ed write to be mmap'ed execute x86/ima: check EFI SetupMode too
2019-06-30IMA: Define a new template field bufPrakhar Srivastava1-3/+4
A buffer(kexec boot command line arguments) measured into IMA measuremnt list cannot be appraised, without already being aware of the buffer contents. Since hashes are non-reversible, raw buffer is needed for validation or regenerating hash for appraisal/attestation. Add support to store/read the buffer contents in HEX. The kexec cmdline hash is stored in the "d-ng" field of the template data. It can be verified using sudo cat /sys/kernel/security/integrity/ima/ascii_runtime_measurements | grep kexec-cmdline | cut -d' ' -f 6 | xxd -r -p | sha256sum - Add two new fields to ima_event_data to hold the buf and buf_len - Add a new template field 'buf' to be used to store/read the buffer data. - Updated process_buffer_meaurement to add the buffer to ima_event_data. process_buffer_measurement added in "Define a new IMA hook to measure the boot command line arguments" - Add a new template policy name ima-buf to represent 'd-ng|n-ng|buf' Signed-off-by: Prakhar Srivastava <prsriva02@gmail.com> Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-06-27keys: Replace uid/gid/perm permissions checking with an ACLDavid Howells2-31/+106
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>
2019-06-27keys: Pass the network namespace into request_key mechanismDavid Howells2-14/+43
Create a request_key_net() function and use it to pass the network namespace domain tag into DNS revolver keys and rxrpc/AFS keys so that keys for different domains can coexist in the same keyring. Signed-off-by: David Howells <dhowells@redhat.com> cc: netdev@vger.kernel.org cc: linux-nfs@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: linux-afs@lists.infradead.org
2019-06-26keys: Add a 'recurse' flag for keyring searchesDavid Howells1-4/+6
Add a 'recurse' flag for keyring searches so that the flag can be omitted and recursion disabled, thereby allowing just the nominated keyring to be searched and none of the children. Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-26keys: Kill off request_key_async{,_with_auxdata}David Howells2-53/+2
Kill off request_key_async{,_with_auxdata}() as they're not currently used. Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-19keys: Cache result of request_key*() temporarily in task_structDavid Howells1-1/+6
If a filesystem uses keys to hold authentication tokens, then it needs a token for each VFS operation that might perform an authentication check - either by passing it to the server, or using to perform a check based on authentication data cached locally. For open files this isn't a problem, since the key should be cached in the file struct since it represents the subject performing operations on that file descriptor. During pathwalk, however, there isn't anywhere to cache the key, except perhaps in the nameidata struct - but that isn't exposed to the filesystems. Further, a pathwalk can incur a lot of operations, calling one or more of the following, for instance: ->lookup() ->permission() ->d_revalidate() ->d_automount() ->get_acl() ->getxattr() on each dentry/inode it encounters - and each one may need to call request_key(). And then, at the end of pathwalk, it will call the actual operation: ->mkdir() ->mknod() ->getattr() ->open() ... which may need to go and get the token again. However, it is very likely that all of the operations on a single dentry/inode - and quite possibly a sequence of them - will all want to use the same authentication token, which suggests that caching it would be a good idea. To this end: (1) Make it so that a positive result of request_key() and co. that didn't require upcalling to userspace is cached temporarily in task_struct. (2) The cache is 1 deep, so a new result displaces the old one. (3) The key is released by exit and by notify-resume. (4) The cache is cleared in a newly forked process. Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-19keys: Provide request_key_rcu()David Howells2-0/+19
Provide a request_key_rcu() function that can be used to request a key under RCU conditions. It can only search and check permissions; it cannot allocate a new key, upcall or wait for an upcall to complete. It may return a partially constructed key. Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-19keys: Move the RCU locks outwards from the keyring search functionsDavid Howells1-1/+1
Move the RCU locks outwards from the keyring search functions so that it will become possible to provide an RCU-capable partial request_key() function in a later commit. Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-19keys: Fix request_key() lack of Link perm check on found keyDavid Howells1-0/+4
The request_key() syscall allows a process to gain access to the 'possessor' permits of any key that grants it Search permission by virtue of request_key() not checking whether a key it finds grants Link permission to the caller. Signed-off-by: David Howells <dhowells@redhat.com>
2019-06-08docs: security: core.rst: Fix several warningsMauro Carvalho Chehab1-6/+10
Multi-line literal markups only work when they're idented at the same level, with is not the case here: Documentation/security/keys/core.rst:1597: WARNING: Inline literal start-string without end-string. Documentation/security/keys/core.rst:1597: WARNING: Inline emphasis start-string without end-string. Documentation/security/keys/core.rst:1597: WARNING: Inline emphasis start-string without end-string. Documentation/security/keys/core.rst:1598: WARNING: Inline emphasis start-string without end-string. Documentation/security/keys/core.rst:1598: WARNING: Inline emphasis start-string without end-string. Documentation/security/keys/core.rst:1600: WARNING: Inline literal start-string without end-string. Documentation/security/keys/core.rst:1600: WARNING: Inline emphasis start-string without end-string. Documentation/security/keys/core.rst:1600: WARNING: Inline emphasis start-string without end-string. Documentation/security/keys/core.rst:1600: WARNING: Inline emphasis start-string without end-string. Documentation/security/keys/core.rst:1600: WARNING: Inline emphasis start-string without end-string. Documentation/security/keys/core.rst:1666: WARNING: Inline literal start-string without end-string. Documentation/security/keys/core.rst:1666: WARNING: Inline emphasis start-string without end-string. Documentation/security/keys/core.rst:1666: WARNING: Inline emphasis start-string without end-string. Documentation/security/keys/core.rst:1666: WARNING: Inline emphasis start-string without end-string. Fix it by using a code-block instead. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-08docs: security: trusted-encrypted.rst: fix code-block tagMauro Carvalho Chehab1-1/+3
The code-block tag is at the wrong place, causing those warnings: Documentation/security/keys/trusted-encrypted.rst:112: WARNING: Literal block expected; none found. Documentation/security/keys/trusted-encrypted.rst:121: WARNING: Unexpected indentation. Documentation/security/keys/trusted-encrypted.rst:122: WARNING: Block quote ends without a blank line; unexpected unindent. Documentation/security/keys/trusted-encrypted.rst:123: WARNING: Block quote ends without a blank line; unexpected unindent. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-30keys: Add a keyctl to move a key between keyringsDavid Howells1-0/+21
Add a keyctl to atomically move a link to a key from one keyring to another. The key must exist in "from" keyring and a flag can be given to cause the operation to fail if there's a matching key already in the "to" keyring. This can be done with: keyctl(KEYCTL_MOVE, key_serial_t key, key_serial_t from_keyring, key_serial_t to_keyring, unsigned int flags); The key being moved must grant Link permission and both keyrings must grant Write permission. flags should be 0 or KEYCTL_MOVE_EXCL, with the latter preventing displacement of a matching key from the "to" keyring. Signed-off-by: David Howells <dhowells@redhat.com>
2019-02-22doc: security: Add kern-doc for lsm_hooks.hKees Cook1-1/+4
There is a lot of kern-doc for the LSM internals, but it wasn't visible in the HTML output. This exposes some formatting flaws in lsm_hooks.h that will be fixed in a later series of patches. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-02-22doc: sctp: Merge and clean up rst filesKees Cook3-166/+175
The SCTP sections were ending up at the top-level table of contents under the security section when they should have be sections with the SCTP chapters. In addition to correcting the section and subsection headings, this merges the SCTP documents into a single file to organize the chapters more clearly, internally linkifies them, and adds the missing SPDX header. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-01-02Merge branch 'next-integrity' of ↵Linus Torvalds1-1/+30
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull integrity updates from James Morris: "In Linux 4.19, a new LSM hook named security_kernel_load_data was upstreamed, allowing LSMs and IMA to prevent the kexec_load syscall. Different signature verification methods exist for verifying the kexec'ed kernel image. This adds additional support in IMA to prevent loading unsigned kernel images via the kexec_load syscall, independently of the IMA policy rules, based on the runtime "secure boot" flag. An initial IMA kselftest is included. In addition, this pull request defines a new, separate keyring named ".platform" for storing the preboot/firmware keys needed for verifying the kexec'ed kernel image's signature and includes the associated IMA kexec usage of the ".platform" keyring. (David Howell's and Josh Boyer's patches for reading the preboot/firmware keys, which were previously posted for a different use case scenario, are included here)" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: integrity: Remove references to module keyring ima: Use inode_is_open_for_write ima: Support platform keyring for kernel appraisal efi: Allow the "db" UEFI variable to be suppressed efi: Import certificates from UEFI Secure Boot efi: Add an EFI signature blob parser efi: Add EFI signature data types integrity: Load certs to the platform keyring integrity: Define a trusted platform keyring selftests/ima: kexec_load syscall test ima: don't measure/appraise files on efivarfs x86/ima: retry detecting secure boot mode docs: Extend trusted keys documentation for TPM 2.0 x86/ima: define arch_get_ima_policy() for x86 ima: add support for arch specific policies ima: refactor ima_init_policy() ima: prevent kexec_load syscall based on runtime secureboot flag x86/ima: define arch_ima_get_secureboot integrity: support new struct public_key_signature encoding field
2018-12-29Merge tag 'docs-5.0' of git://git.lwn.net/linuxLinus Torvalds2-5/+5
Pull documentation update from Jonathan Corbet: "A fairly normal cycle for documentation stuff. We have a new document on perf security, more Italian translations, more improvements to the memory-management docs, improvements to the pathname lookup documentation, and the usual array of smaller fixes. As is often the case, there are a few reaches outside of Documentation/ to adjust kerneldoc comments" * tag 'docs-5.0' of git://git.lwn.net/linux: (38 commits) docs: improve pathname-lookup document structure configfs: fix wrong name of struct in documentation docs/mm-api: link slab_common.c to "The Slab Cache" section slab: make kmem_cache_create{_usercopy} description proper kernel-doc doc:process: add links where missing docs/core-api: make mm-api.rst more structured x86, boot: documentation whitespace fixup Documentation: devres: note checking needs when converting doc:it: add some process/* translations doc:it: fixes in process/1.Intro Documentation: convert path-lookup from markdown to resturctured text Documentation/admin-guide: update admin-guide index.rst Documentation/admin-guide: introduce perf-security.rst file scripts/kernel-doc: Fix struct and struct field attribute processing Documentation: dev-tools: Fix typos in index.rst Correct gen_init_cpio tool's documentation Document /proc/pid PID reuse behavior Documentation: update path-lookup.md for parallel lookups Documentation: Use "while" instead of "whilst" dmaengine: Add mailing list address to the documentation ...
2018-12-13keys-encrypted: add nvdimm key format type to encrypted keysDave Jiang1-1/+5
Adding nvdimm key format type to encrypted keys in order to limit the size of the key to 32bytes. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-12-11docs: Extend trusted keys documentation for TPM 2.0Stefan Berger1-1/+30
Extend the documentation for trusted keys with documentation for how to set up a key for a TPM 2.0 so it can be used with a TPM 2.0 as well. Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Jerry Snitselaar <jsnitsel@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-11-20Documentation: Use "while" instead of "whilst"Will Deacon2-5/+5
Whilst making an unrelated change to some Documentation, Linus sayeth: | Afaik, even in Britain, "whilst" is unusual and considered more | formal, and "while" is the common word. | | [...] | | Can we just admit that we work with computers, and we don't need to | use þe eald Englisc spelling of words that most of the world never | uses? dictionary.com refers to the word as "Chiefly British", which is probably an undesirable attribute for technical documentation. Replace all occurrences under Documentation/ with "while". Cc: David Howells <dhowells@redhat.com> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-11-01Merge branch 'next-keys2' of ↵Linus Torvalds1-0/+217
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull keys updates from James Morris: "Provide five new operations in the key_type struct that can be used to provide access to asymmetric key operations. These will be implemented for the asymmetric key type in a later patch and may refer to a key retained in RAM by the kernel or a key retained in crypto hardware. int (*asym_query)(const struct kernel_pkey_params *params, struct kernel_pkey_query *info); int (*asym_eds_op)(struct kernel_pkey_params *params, const void *in, void *out); int (*asym_verify_signature)(struct kernel_pkey_params *params, const void *in, const void *in2); Since encrypt, decrypt and sign are identical in their interfaces, they're rolled together in the asym_eds_op() operation and there's an operation ID in the params argument to distinguish them. Verify is different in that we supply the data and the signature instead and get an error value (or 0) as the only result on the expectation that this may well be how a hardware crypto device may work" * 'next-keys2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (22 commits) KEYS: asym_tpm: Add support for the sign operation [ver #2] KEYS: asym_tpm: Implement tpm_sign [ver #2] KEYS: asym_tpm: Implement signature verification [ver #2] KEYS: asym_tpm: Implement the decrypt operation [ver #2] KEYS: asym_tpm: Implement tpm_unbind [ver #2] KEYS: asym_tpm: Add loadkey2 and flushspecific [ver #2] KEYS: Move trusted.h to include/keys [ver #2] KEYS: trusted: Expose common functionality [ver #2] KEYS: asym_tpm: Implement encryption operation [ver #2] KEYS: asym_tpm: Implement pkey_query [ver #2] KEYS: Add parser for TPM-based keys [ver #2] KEYS: asym_tpm: extract key size & public key [ver #2] KEYS: asym_tpm: add skeleton for asym_tpm [ver #2] crypto: rsa-pkcs1pad: Allow hash to be optional [ver #2] KEYS: Implement PKCS#8 RSA Private Key parser [ver #2] KEYS: Implement encrypt, decrypt and sign for software asymmetric key [ver #2] KEYS: Allow the public_key struct to hold a private key [ver #2] KEYS: Provide software public key query function [ver #2] KEYS: Make the X.509 and PKCS7 parsers supply the sig encoding type [ver #2] KEYS: Provide missing asymmetric key subops for new key type ops [ver #2] ...
2018-11-01Merge tag 'stackleak-v4.20-rc1' of ↵Linus Torvalds1-5/+5
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull stackleak gcc plugin from Kees Cook: "Please pull this new GCC plugin, stackleak, for v4.20-rc1. This plugin was ported from grsecurity by Alexander Popov. It provides efficient stack content poisoning at syscall exit. This creates a defense against at least two classes of flaws: - Uninitialized stack usage. (We continue to work on improving the compiler to do this in other ways: e.g. unconditional zero init was proposed to GCC and Clang, and more plugin work has started too). - Stack content exposure. By greatly reducing the lifetime of valid stack contents, exposures via either direct read bugs or unknown cache side-channels become much more difficult to exploit. This complements the existing buddy and heap poisoning options, but provides the coverage for stacks. The x86 hooks are included in this series (which have been reviewed by Ingo, Dave Hansen, and Thomas Gleixner). The arm64 hooks have already been merged through the arm64 tree (written by Laura Abbott and reviewed by Mark Rutland and Will Deacon). With VLAs having been removed this release, there is no need for alloca() protection, so it has been removed from the plugin" * tag 'stackleak-v4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: arm64: Drop unneeded stackleak_check_alloca() stackleak: Allow runtime disabling of kernel stack erasing doc: self-protection: Add information about STACKLEAK feature fs/proc: Show STACKLEAK metrics in the /proc file system lkdtm: Add a test for STACKLEAK gcc-plugins: Add STACKLEAK plugin for tracking the kernel stack x86/entry: Add STACKLEAK erasing the kernel stack at the end of syscalls
2018-10-26KEYS: Provide keyctls to drive the new key type ops for asymmetric keys [ver #2]David Howells1-0/+111
Provide five keyctl functions that permit userspace to make use of the new key type ops for accessing and driving asymmetric keys. (*) Query an asymmetric key. long keyctl(KEYCTL_PKEY_QUERY, key_serial_t key, unsigned long reserved, struct keyctl_pkey_query *info); Get information about an asymmetric key. The information is returned in the keyctl_pkey_query struct: __u32 supported_ops; A bit mask of flags indicating which ops are supported. This is constructed from a bitwise-OR of: KEYCTL_SUPPORTS_{ENCRYPT,DECRYPT,SIGN,VERIFY} __u32 key_size; The size in bits of the key. __u16 max_data_size; __u16 max_sig_size; __u16 max_enc_size; __u16 max_dec_size; The maximum sizes in bytes of a blob of data to be signed, a signature blob, a blob to be encrypted and a blob to be decrypted. reserved must be set to 0. This is intended for future use to hand over one or more passphrases needed unlock a key. If successful, 0 is returned. If the key is not an asymmetric key, EOPNOTSUPP is returned. (*) Encrypt, decrypt, sign or verify a blob using an asymmetric key. long keyctl(KEYCTL_PKEY_ENCRYPT, const struct keyctl_pkey_params *params, const char *info, const void *in, void *out); long keyctl(KEYCTL_PKEY_DECRYPT, const struct keyctl_pkey_params *params, const char *info, const void *in, void *out); long keyctl(KEYCTL_PKEY_SIGN, const struct keyctl_pkey_params *params, const char *info, const void *in, void *out); long keyctl(KEYCTL_PKEY_VERIFY, const struct keyctl_pkey_params *params, const char *info, const void *in, const void *in2); Use an asymmetric key to perform a public-key cryptographic operation a blob of data. The parameter block pointed to by params contains a number of integer values: __s32 key_id; __u32 in_len; __u32 out_len; __u32 in2_len; For a given operation, the in and out buffers are used as follows: Operation ID in,in_len out,out_len in2,in2_len ======================= =============== =============== =========== KEYCTL_PKEY_ENCRYPT Raw data Encrypted data - KEYCTL_PKEY_DECRYPT Encrypted data Raw data - KEYCTL_PKEY_SIGN Raw data Signature - KEYCTL_PKEY_VERIFY Raw data - Signature info is a string of key=value pairs that supply supplementary information. The __spare space in the parameter block must be set to 0. This is intended, amongst other things, to allow the passing of passphrases required to unlock a key. If successful, encrypt, decrypt and sign all return the amount of data written into the output buffer. Verification returns 0 on success. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: Denis Kenzior <denkenz@gmail.com> Tested-by: Denis Kenzior <denkenz@gmail.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-26KEYS: Provide key type operations for asymmetric key ops [ver #2]David Howells1-0/+106
Provide five new operations in the key_type struct that can be used to provide access to asymmetric key operations. These will be implemented for the asymmetric key type in a later patch and may refer to a key retained in RAM by the kernel or a key retained in crypto hardware. int (*asym_query)(const struct kernel_pkey_params *params, struct kernel_pkey_query *info); int (*asym_eds_op)(struct kernel_pkey_params *params, const void *in, void *out); int (*asym_verify_signature)(struct kernel_pkey_params *params, const void *in, const void *in2); Since encrypt, decrypt and sign are identical in their interfaces, they're rolled together in the asym_eds_op() operation and there's an operation ID in the params argument to distinguish them. Verify is different in that we supply the data and the signature instead and get an error value (or 0) as the only result on the expectation that this may well be how a hardware crypto device may work. Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: Denis Kenzior <denkenz@gmail.com> Tested-by: Denis Kenzior <denkenz@gmail.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-24Merge tag 'docs-4.20' of git://git.lwn.net/linuxLinus Torvalds1-4/+4
Pull documentation updates from Jonathan Corbet: "This is a fairly typical cycle for documentation. There's some welcome readability improvements for the formatted output, some LICENSES updates including the addition of the ISC license, the removal of the unloved and unmaintained 00-INDEX files, the deprecated APIs document from Kees, more MM docs from Mike Rapoport, and the usual pile of typo fixes and corrections" * tag 'docs-4.20' of git://git.lwn.net/linux: (41 commits) docs: Fix typos in histogram.rst docs: Introduce deprecated APIs list kernel-doc: fix declaration type determination doc: fix a typo in adding-syscalls.rst docs/admin-guide: memory-hotplug: remove table of contents doc: printk-formats: Remove bogus kobject references for device nodes Documentation: preempt-locking: Use better example dm flakey: Document "error_writes" feature docs/completion.txt: Fix a couple of punctuation nits LICENSES: Add ISC license text LICENSES: Add note to CDDL-1.0 license that it should not be used docs/core-api: memory-hotplug: add some details about locking internals docs/core-api: rename memory-hotplug-notifier to memory-hotplug docs: improve readability for people with poorer eyesight yama: clarify ptrace_scope=2 in Yama documentation docs/vm: split memory hotplug notifier description to Documentation/core-api docs: move memory hotplug description into admin-guide/mm doc: Fix acronym "FEKEK" in ecryptfs docs: fix some broken documentation references iommu: Fix passthrough option documentation ...
2018-10-09security: fix LSM description locationRandy Dunlap1-1/+1
Acked-by: Kees Cook <keescook@chromium.org> Fix Documentation location reference for where LSM descriptions should be placed. Suggested-by: Kees Cook <keescook@chromium.org> Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: linux-security-module@vger.kernel.org Signed-off-by: James Morris <james.morris@microsoft.com>
2018-09-20doc: Fix acronym "FEKEK" in ecryptfsFelix Eckhofer1-4/+4
"FEFEK" was incorrectly used as acronym for "File Encryption Key Encryption Key". This replaces all occurences with "FEKEK". Signed-off-by: Felix Eckhofer <felix@eckhofer.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-09-04doc: self-protection: Add information about STACKLEAK featureAlexander Popov1-5/+5
Add information about STACKLEAK feature to the "Memory poisoning" section of self-protection.rst. Signed-off-by: Alexander Popov <alex.popov@linux.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-14Kbuild: rename CC_STACKPROTECTOR[_STRONG] config variablesLinus Torvalds1-1/+1
The changes to automatically test for working stack protector compiler support in the Kconfig files removed the special STACKPROTECTOR_AUTO option that picked the strongest stack protector that the compiler supported. That was all a nice cleanup - it makes no sense to have the AUTO case now that the Kconfig phase can just determine the compiler support directly. HOWEVER. It also meant that doing "make oldconfig" would now _disable_ the strong stackprotector if you had AUTO enabled, because in a legacy config file, the sane stack protector configuration would look like CONFIG_HAVE_CC_STACKPROTECTOR=y # CONFIG_CC_STACKPROTECTOR_NONE is not set # CONFIG_CC_STACKPROTECTOR_REGULAR is not set # CONFIG_CC_STACKPROTECTOR_STRONG is not set CONFIG_CC_STACKPROTECTOR_AUTO=y and when you ran this through "make oldconfig" with the Kbuild changes, it would ask you about the regular CONFIG_CC_STACKPROTECTOR (that had been renamed from CONFIG_CC_STACKPROTECTOR_REGULAR to just CONFIG_CC_STACKPROTECTOR), but it would think that the STRONG version used to be disabled (because it was really enabled by AUTO), and would disable it in the new config, resulting in: CONFIG_HAVE_CC_STACKPROTECTOR=y CONFIG_CC_HAS_STACKPROTECTOR_NONE=y CONFIG_CC_STACKPROTECTOR=y # CONFIG_CC_STACKPROTECTOR_STRONG is not set CONFIG_CC_HAS_SANE_STACKPROTECTOR=y That's dangerously subtle - people could suddenly find themselves with the weaker stack protector setup without even realizing. The solution here is to just rename not just the old RECULAR stack protector option, but also the strong one. This does that by just removing the CC_ prefix entirely for the user choices, because it really is not about the compiler support (the compiler support now instead automatially impacts _visibility_ of the options to users). This results in "make oldconfig" actually asking the user for their choice, so that we don't have any silent subtle security model changes. The end result would generally look like this: CONFIG_HAVE_CC_STACKPROTECTOR=y CONFIG_CC_HAS_STACKPROTECTOR_NONE=y CONFIG_STACKPROTECTOR=y CONFIG_STACKPROTECTOR_STRONG=y CONFIG_CC_HAS_SANE_STACKPROTECTOR=y where the "CC_" versions really are about internal compiler infrastructure, not the user selections. Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-05-08docs: */index.rst: Add newer documents to their respective index.rstMauro Carvalho Chehab1-0/+2
A number of new docs were added, but they're currently not on the index.rst from the session they're supposed to be, causing Sphinx warnings. Add them. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-03-20selinux: Update SELinux SCTP documentationRichard Haines1-5/+6
Update SELinux-sctp.rst "SCTP Peer Labeling" section to reflect how the association permission is validated. Reported-by: Dominick Grift <dac.override@gmail.com> Signed-off-by: Richard Haines <richard_c_haines@btinternet.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-02-26selinux: Add SCTP supportRichard Haines1-0/+157
The SELinux SCTP implementation is explained in: Documentation/security/SELinux-sctp.rst Signed-off-by: Richard Haines <richard_c_haines@btinternet.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-02-22security: Add support for SCTP security hooksRichard Haines1-0/+175
The SCTP security hooks are explained in: Documentation/security/LSM-sctp.rst Signed-off-by: Richard Haines <richard_c_haines@btinternet.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-01-08Documentation: security/credentials.rst: explain need to sort group_listNeilBrown1-0/+7
This patch updates the documentation with the observations that led to commit bdcf0a423ea1 ("kernel: make groups_sort calling a responsibility group_info allocators") and the new behaviour required. Specifically that groups_sort() should be called on a new group_list before set_groups() or set_current_groups() is called. Signed-off-by: NeilBrown <neilb@suse.com> [jc: use proper :c:func: references] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-12-21doc: add documentation on printing kernel addressesTobin C. Harding1-0/+15
Hashing addresses printed with printk specifier %p was implemented recently. During development a number of issues were raised regarding leaking kernel addresses to userspace. Other documentation was updated but security/self-protection missed out. Add self-protection documentation regarding printing kernel addresses. Signed-off-by: Tobin C. Harding <me@tobin.cc> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-11-15KEYS: fix in-kernel documentation for keyctl_read()Eric Biggers1-5/+5
When keyctl_read() is passed a buffer that is too small, the behavior is inconsistent. Some key types will fill as much of the buffer as possible, while others won't copy anything. Moreover, the in-kernel documentation contradicted the man page on this point. Update the in-kernel documentation to say that this point is unspecified. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: David Howells <dhowells@redhat.com>
2017-10-12Documentation: fix security related doc refsTom Saeger3-3/+3
Make security document refs valid. Signed-off-by: Tom Saeger <tom.saeger@oracle.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-08-30docs: ReSTify table of contents in core.rstJosh Holland1-11/+1
Sphinx will now generate the table of contents automatically, which avoids having the ToC getting out of sync with the rest of the document. Signed-off-by: Josh Holland <anowlcalledjosh@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-08-24docs: Fix paths in security/keysJosh Holland3-4/+4
Several paths in the security/keys documentation were incorrect. Signed-off-by: Josh Holland <anowlcalledjosh@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-07-14KEYS: Add documentation for asymmetric keyring restrictionsMat Martineau1-0/+6
Provide more specific examples of keyring restrictions as applied to X.509 signature chain verification. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-05-18docs: Fix some formatting issues in request-key.rstJonathan Corbet1-3/+3
The white space in the big enumerated list was inconsistent, leading to some strange formatting artifacts. Signed-off-by: Jonathan Corbet <corbet@lwn.net>