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2024-02-16ima: Move to LSM infrastructureRoberto Sassu1-0/+1
Move hardcoded IMA function calls (not appraisal-specific functions) from various places in the kernel to the LSM infrastructure, by introducing a new LSM named 'ima' (at the end of the LSM list and always enabled like 'integrity'). Having IMA before EVM in the Makefile is sufficient to preserve the relative order of the new 'ima' LSM in respect to the upcoming 'evm' LSM, and thus the order of IMA and EVM function calls as when they were hardcoded. Make moved functions as static (except ima_post_key_create_or_update(), which is not in ima_main.c), and register them as implementation of the respective hooks in the new function init_ima_lsm(). Select CONFIG_SECURITY_PATH, to ensure that the path-based LSM hook path_post_mknod is always available and ima_post_path_mknod() is always executed to mark files as new, as before the move. A slight difference is that IMA and EVM functions registered for the inode_post_setattr, inode_post_removexattr, path_post_mknod, inode_post_create_tmpfile, inode_post_set_acl and inode_post_remove_acl won't be executed for private inodes. Since those inodes are supposed to be fs-internal, they should not be of interest to IMA or EVM. The S_PRIVATE flag is used for anonymous inodes, hugetlbfs, reiserfs xattrs, XFS scrub and kernel-internal tmpfs files. Conditionally register ima_post_key_create_or_update() if CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS is enabled. Also, conditionally register ima_kernel_module_request() if CONFIG_INTEGRITY_ASYMMETRIC_KEYS is enabled. Finally, add the LSM_ID_IMA case in lsm_list_modules_test.c. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Acked-by: Chuck Lever <chuck.lever@oracle.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2023-11-27ima: Remove EXPERIMENTAL from KconfigEric Snowberg1-1/+1
Remove the EXPERIMENTAL from the IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY Kconfig now that digitalSignature usage enforcement is set. Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> link: https://lore.kernel.org/all/20230508220708.2888510-4-eric.snowberg@oracle.com/ Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2023-11-27ima: Reword IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARYEric Snowberg1-5/+5
When the machine keyring is enabled, it may be used as a trust source for the .ima keyring. Add a reference to this in IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY. Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2023-09-27ima: rework CONFIG_IMA dependency blockArnd Bergmann1-12/+6
Changing the direct dependencies of IMA_BLACKLIST_KEYRING and IMA_LOAD_X509 caused them to no longer depend on IMA, but a a configuration without IMA results in link failures: arm-linux-gnueabi-ld: security/integrity/iint.o: in function `integrity_load_keys': iint.c:(.init.text+0xd8): undefined reference to `ima_load_x509' aarch64-linux-ld: security/integrity/digsig_asymmetric.o: in function `asymmetric_verify': digsig_asymmetric.c:(.text+0x104): undefined reference to `ima_blacklist_keyring' Adding explicit dependencies on IMA would fix this, but a more reliable way to do this is to enclose the entire Kconfig file in an 'if IMA' block. This also allows removing the existing direct dependencies. Fixes: be210c6d3597f ("ima: Finish deprecation of IMA_TRUSTED_KEYRING Kconfig") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2023-09-27ima: Finish deprecation of IMA_TRUSTED_KEYRING KconfigOleksandr Tymoshenko1-2/+2
The removal of IMA_TRUSTED_KEYRING made IMA_LOAD_X509 and IMA_BLACKLIST_KEYRING unavailable because the latter two depend on the former. Since IMA_TRUSTED_KEYRING was deprecated in favor of INTEGRITY_TRUSTED_KEYRING use it as a dependency for the two Kconfigs affected by the deprecation. Fixes: 5087fd9e80e5 ("ima: Remove deprecated IMA_TRUSTED_KEYRING Kconfig") Signed-off-by: Oleksandr Tymoshenko <ovt@google.com> Reviewed-by: Nayna Jain <nayna@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2023-08-30Merge tag 'integrity-v6.6' of ↵Linus Torvalds1-12/+0
git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity Pull integrity subsystem updates from Mimi Zohar: - With commit 099f26f22f58 ("integrity: machine keyring CA configuration") certificates may be loaded onto the IMA keyring, directly or indirectly signed by keys on either the "builtin" or the "machine" keyrings. With the ability for the system/machine owner to sign the IMA policy itself without needing to recompile the kernel, update the IMA architecture specific policy rules to require the IMA policy itself be signed. [ As commit 099f26f22f58 was upstreamed in linux-6.4, updating the IMA architecture specific policy now to require signed IMA policies may break userspace expectations. ] - IMA only checked the file data hash was not on the system blacklist keyring for files with an appended signature (e.g. kernel modules, Power kernel image). Check all file data hashes regardless of how it was signed - Code cleanup, and a kernel-doc update * tag 'integrity-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity: kexec_lock: Replace kexec_mutex() by kexec_lock() in two comments ima: require signed IMA policy when UEFI secure boot is enabled integrity: Always reference the blacklist keyring with appraisal ima: Remove deprecated IMA_TRUSTED_KEYRING Kconfig
2023-08-17integrity: Enforce digitalSignature usage in the ima and evm keyringsEric Snowberg1-1/+2
After being vouched for by a system keyring, only allow keys into the .ima and .evm keyrings that have the digitalSignature usage field set. Link: https://lore.kernel.org/all/41dffdaeb7eb7840f7e38bc691fbda836635c9f9.camel@linux.ibm.com Suggested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com> Acked-and-tested-by: Mimi Zohar <zohar@linux.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
2023-08-01ima: Remove deprecated IMA_TRUSTED_KEYRING KconfigNayna Jain1-12/+0
Time to remove "IMA_TRUSTED_KEYRING". Fixes: f4dc37785e9b ("integrity: define '.evm' as a builtin 'trusted' keyring") # v4.5+ Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2023-03-16IMA: allow/fix UML buildsRandy Dunlap1-1/+1
UML supports HAS_IOMEM since 0bbadafdc49d (um: allow disabling NO_IOMEM). Current IMA build on UML fails on allmodconfig (with TCG_TPM=m): ld: security/integrity/ima/ima_queue.o: in function `ima_add_template_entry': ima_queue.c:(.text+0x2d9): undefined reference to `tpm_pcr_extend' ld: security/integrity/ima/ima_init.o: in function `ima_init': ima_init.c:(.init.text+0x43f): undefined reference to `tpm_default_chip' ld: security/integrity/ima/ima_crypto.o: in function `ima_calc_boot_aggregate_tfm': ima_crypto.c:(.text+0x1044): undefined reference to `tpm_pcr_read' ld: ima_crypto.c:(.text+0x10d8): undefined reference to `tpm_pcr_read' Modify the IMA Kconfig entry so that it selects TCG_TPM if HAS_IOMEM is set, regardless of the UML Kconfig setting. This updates TCG_TPM from =m to =y and fixes the linker errors. Fixes: f4a0391dfa91 ("ima: fix Kconfig dependencies") Cc: Stable <stable@vger.kernel.org> # v5.14+ Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Fabio Estevam <festevam@gmail.com> Cc: Richard Weinberger <richard@nod.at> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: linux-um@lists.infradead.org Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-11-29ima: Fix hash dependency to correct algorithmTianjia Zhang1-1/+1
Commit d2825fa9365d ("crypto: sm3,sm4 - move into crypto directory") moves the SM3 and SM4 stand-alone library and the algorithm implementation for the Crypto API into the same directory, and the corresponding relationship of Kconfig is modified, CONFIG_CRYPTO_SM3/4 corresponds to the stand-alone library of SM3/4, and CONFIG_CRYPTO_SM3/4_GENERIC corresponds to the algorithm implementation for the Crypto API. Therefore, it is necessary for this module to depend on the correct algorithm. Fixes: d2825fa9365d ("crypto: sm3,sm4 - move into crypto directory") Cc: Jason A. Donenfeld <Jason@zx2c4.com> Cc: stable@vger.kernel.org # v5.19+ Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-04-07ima: remove the IMA_TEMPLATE Kconfig optionGUO Zihua1-8/+6
The original 'ima' measurement list template contains a hash, defined as 20 bytes, and a null terminated pathname, limited to 255 characters. Other measurement list templates permit both larger hashes and longer pathnames. When the "ima" template is configured as the default, a new measurement list template (ima_template=) must be specified before specifying a larger hash algorithm (ima_hash=) on the boot command line. To avoid this boot command line ordering issue, remove the legacy "ima" template configuration option, allowing it to still be specified on the boot command line. The root cause of this issue is that during the processing of ima_hash, we would try to check whether the hash algorithm is compatible with the template. If the template is not set at the moment we do the check, we check the algorithm against the configured default template. If the default template is "ima", then we reject any hash algorithm other than sha1 and md5. For example, if the compiled default template is "ima", and the default algorithm is sha1 (which is the current default). In the cmdline, we put in "ima_hash=sha256 ima_template=ima-ng". The expected behavior would be that ima starts with ima-ng as the template and sha256 as the hash algorithm. However, during the processing of "ima_hash=", "ima_template=" has not been processed yet, and hash_setup would check the configured hash algorithm against the compiled default: ima, and reject sha256. So at the end, the hash algorithm that is actually used will be sha1. With template "ima" removed from the configured default, we ensure that the default tempalte would at least be "ima-ng" which allows for basically any hash algorithm. This change would not break the algorithm compatibility checks for IMA. Fixes: 4286587dccd43 ("ima: add Kconfig default measurement list template") Signed-off-by: GUO Zihua <guozihua@huawei.com> Cc: <Stable@vger.kernel.org> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2021-08-17IMA: remove the dependency on CRYPTO_MD5THOBY Simon1-1/+0
MD5 is a weak digest algorithm that shouldn't be used for cryptographic operation. It hinders the efficiency of a patch set that aims to limit the digests allowed for the extended file attribute namely security.ima. MD5 is no longer a requirement for IMA, nor should it be used there. The sole place where we still use the MD5 algorithm inside IMA is setting the ima_hash algorithm to MD5, if the user supplies 'ima_hash=md5' parameter on the command line. With commit ab60368ab6a4 ("ima: Fallback to the builtin hash algorithm"), setting "ima_hash=md5" fails gracefully when CRYPTO_MD5 is not set: ima: Can not allocate md5 (reason: -2) ima: Allocating md5 failed, going to use default hash algorithm sha256 Remove the CRYPTO_MD5 dependency for IMA. Signed-off-by: THOBY Simon <Simon.THOBY@viveris.fr> Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> [zohar@linux.ibm.com: include commit number in patch description for stable.] Cc: stable@vger.kernel.org # 4.17 Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2021-06-11IMA: support for duplicate measurement recordsTushar Sugandhi1-0/+7
IMA measures contents of a given file/buffer/critical-data record, and properly re-measures it on change. However, IMA does not measure the duplicate value for a given record, since TPM extend is a very expensive operation. For example, if the record changes from value 'v#1' to 'v#2', and then back to 'v#1', IMA will not measure and log the last change to 'v#1', since the hash of 'v#1' for that record is already present in the IMA htable. This limits the ability of an external attestation service to accurately determine the current state of the system. The service would incorrectly conclude that the latest value of the given record on the system is 'v#2', and act accordingly. Define and use a new Kconfig option IMA_DISABLE_HTABLE to permit duplicate records in the IMA measurement list. In addition to the duplicate measurement records described above, other duplicate file measurement records may be included in the log, when CONFIG_IMA_DISABLE_HTABLE is enabled. For example, - i_version is not enabled, - i_generation changed, - same file present on different filesystems, - an inode is evicted from dcache Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Reviewed-by: Petr Vorel <pvorel@suse.cz> [zohar@linux.ibm.com: updated list of duplicate measurement records] Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-08-12Merge tag 'for-v5.9' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "A couple of minor documentation updates only for this release" * tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: LSM: drop duplicated words in header file comments Replace HTTP links with HTTPS ones: security
2020-08-06Replace HTTP links with HTTPS ones: securityAlexander A. Klimov1-1/+1
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de> Acked-by: John Johansen <john.johansen@canonical.com> Signed-off-by: James Morris <jmorris@namei.org>
2020-07-21ima: move APPRAISE_BOOTPARAM dependency on ARCH_POLICY to runtimeBruno Meneguele1-1/+1
The IMA_APPRAISE_BOOTPARAM config allows enabling different "ima_appraise=" modes - log, fix, enforce - at run time, but not when IMA architecture specific policies are enabled.  This prevents properly labeling the filesystem on systems where secure boot is supported, but not enabled on the platform.  Only when secure boot is actually enabled should these IMA appraise modes be disabled. This patch removes the compile time dependency and makes it a runtime decision, based on the secure boot state of that platform. Test results as follows: -> x86-64 with secure boot enabled [ 0.015637] Kernel command line: <...> ima_policy=appraise_tcb ima_appraise=fix [ 0.015668] ima: Secure boot enabled: ignoring ima_appraise=fix boot parameter option -> powerpc with secure boot disabled [ 0.000000] Kernel command line: <...> ima_policy=appraise_tcb ima_appraise=fix [ 0.000000] Secure boot mode disabled -> Running the system without secure boot and with both options set: CONFIG_IMA_APPRAISE_BOOTPARAM=y CONFIG_IMA_ARCH_POLICY=y Audit prompts "missing-hash" but still allow execution and, consequently, filesystem labeling: type=INTEGRITY_DATA msg=audit(07/09/2020 12:30:27.778:1691) : pid=4976 uid=root auid=root ses=2 subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 op=appraise_data cause=missing-hash comm=bash name=/usr/bin/evmctl dev="dm-0" ino=493150 res=no Cc: stable@vger.kernel.org Fixes: d958083a8f64 ("x86/ima: define arch_get_ima_policy() for x86") Signed-off-by: Bruno Meneguele <bmeneg@redhat.com> Cc: stable@vger.kernel.org # 5.0 Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-21ima: AppArmor satisfies the audit rule requirementsTyler Hicks1-1/+1
AppArmor meets all the requirements for IMA in terms of audit rules since commit e79c26d04043 ("apparmor: Add support for audit rule filtering"). Update IMA's Kconfig section for CONFIG_IMA_LSM_RULES to reflect this. Fixes: e79c26d04043 ("apparmor: Add support for audit rule filtering") Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-03-12ima: add a new CONFIG for loading arch-specific policiesNayna Jain1-0/+7
Every time a new architecture defines the IMA architecture specific functions - arch_ima_get_secureboot() and arch_ima_get_policy(), the IMA include file needs to be updated. To avoid this "noise", this patch defines a new IMA Kconfig IMA_SECURE_AND_OR_TRUSTED_BOOT option, allowing the different architectures to select it. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Philipp Rudo <prudo@linux.ibm.com> (s390) Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-02-18ima: add sm3 algorithm to hash algorithm configuration listTianjia Zhang1-0/+5
sm3 has been supported by the ima hash algorithm, but it is not yet in the Kconfig configuration list. After adding, both ima and tpm2 can support sm3 well. Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-01-23IMA: Define workqueue for early boot key measurementsLakshmi Ramasubramanian1-0/+6
Measuring keys requires a custom IMA policy to be loaded. Keys created or updated before a custom IMA policy is loaded should be queued and will be processed after a custom policy is loaded. This patch defines a workqueue for queuing keys when a custom IMA policy has not yet been loaded. An intermediate Kconfig boolean option namely IMA_QUEUE_EARLY_BOOT_KEYS is used to declare the workqueue functions. A flag namely ima_process_keys is used to check if the key should be queued or should be processed immediately. Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-01-09IMA: fix measuring asymmetric keys KconfigLakshmi Ramasubramanian1-0/+6
As a result of the asymmetric public keys subtype Kconfig option being defined as tristate, with the existing IMA Makefile, ima_asymmetric_keys.c could be built as a kernel module. To prevent this from happening, this patch defines and uses an intermediate Kconfig boolean option named IMA_MEASURE_ASYMMETRIC_KEYS. Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Suggested-by: James.Bottomley <James.Bottomley@HansenPartnership.com> Cc: David Howells <dhowells@redhat.com> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Reported-by: kbuild test robot <lkp@intel.com> # ima_asymmetric_keys.c is built as a kernel module. Fixes: 88e70da170e8 ("IMA: Define an IMA hook to measure keys") Fixes: cb1aa3823c92 ("KEYS: Call the IMA hook to measure keys") [zohar@linux.ibm.com: updated patch description] Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-09-28Merge branch 'next-lockdown' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull kernel lockdown mode from James Morris: "This is the latest iteration of the kernel lockdown patchset, from Matthew Garrett, David Howells and others. From the original description: This patchset introduces an optional kernel lockdown feature, intended to strengthen the boundary between UID 0 and the kernel. When enabled, various pieces of kernel functionality are restricted. Applications that rely on low-level access to either hardware or the kernel may cease working as a result - therefore this should not be enabled without appropriate evaluation beforehand. The majority of mainstream distributions have been carrying variants of this patchset for many years now, so there's value in providing a doesn't meet every distribution requirement, but gets us much closer to not requiring external patches. There are two major changes since this was last proposed for mainline: - Separating lockdown from EFI secure boot. Background discussion is covered here: https://lwn.net/Articles/751061/ - Implementation as an LSM, with a default stackable lockdown LSM module. This allows the lockdown feature to be policy-driven, rather than encoding an implicit policy within the mechanism. The new locked_down LSM hook is provided to allow LSMs to make a policy decision around whether kernel functionality that would allow tampering with or examining the runtime state of the kernel should be permitted. The included lockdown LSM provides an implementation with a simple policy intended for general purpose use. This policy provides a coarse level of granularity, controllable via the kernel command line: lockdown={integrity|confidentiality} Enable the kernel lockdown feature. If set to integrity, kernel features that allow userland to modify the running kernel are disabled. If set to confidentiality, kernel features that allow userland to extract confidential information from the kernel are also disabled. This may also be controlled via /sys/kernel/security/lockdown and overriden by kernel configuration. New or existing LSMs may implement finer-grained controls of the lockdown features. Refer to the lockdown_reason documentation in include/linux/security.h for details. The lockdown feature has had signficant design feedback and review across many subsystems. This code has been in linux-next for some weeks, with a few fixes applied along the way. Stephen Rothwell noted that commit 9d1f8be5cf42 ("bpf: Restrict bpf when kernel lockdown is in confidentiality mode") is missing a Signed-off-by from its author. Matthew responded that he is providing this under category (c) of the DCO" * 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits) kexec: Fix file verification on S390 security: constify some arrays in lockdown LSM lockdown: Print current->comm in restriction messages efi: Restrict efivar_ssdt_load when the kernel is locked down tracefs: Restrict tracefs when the kernel is locked down debugfs: Restrict debugfs when the kernel is locked down kexec: Allow kexec_file() with appropriate IMA policy when locked down lockdown: Lock down perf when in confidentiality mode bpf: Restrict bpf when kernel lockdown is in confidentiality mode lockdown: Lock down tracing and perf kprobes when in confidentiality mode lockdown: Lock down /proc/kcore x86/mmiotrace: Lock down the testmmiotrace module lockdown: Lock down module params that specify hardware parameters (eg. ioport) lockdown: Lock down TIOCSSERIAL lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down acpi: Disable ACPI table override if the kernel is locked down acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down ACPI: Limit access to custom_method when the kernel is locked down x86/msr: Restrict MSR access when the kernel is locked down x86: Lock down IO port access when the kernel is locked down ...
2019-08-20kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCEJiri Bohac1-1/+1
This is a preparatory patch for kexec_file_load() lockdown. A locked down kernel needs to prevent unsigned kernel images from being loaded with kexec_file_load(). Currently, the only way to force the signature verification is compiling with KEXEC_VERIFY_SIG. This prevents loading usigned images even when the kernel is not locked down at runtime. This patch splits KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE. Analogous to the MODULE_SIG and MODULE_SIG_FORCE for modules, KEXEC_SIG turns on the signature verification but allows unsigned images to be loaded. KEXEC_SIG_FORCE disallows images without a valid signature. Signed-off-by: Jiri Bohac <jbohac@suse.cz> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Matthew Garrett <mjg59@google.com> cc: kexec@lists.infradead.org Signed-off-by: James Morris <jmorris@namei.org>
2019-08-06ima: Implement support for module-style appended signaturesThiago Jung Bauermann1-0/+3
Implement the appraise_type=imasig|modsig option, allowing IMA to read and verify modsig signatures. In case a file has both an xattr signature and an appended modsig, IMA will only use the appended signature if the key used by the xattr signature isn't present in the IMA or platform keyring. Because modsig verification needs to convert from an integrity keyring id to the keyring itself, add an integrity_keyring_from_id() function in digsig.c so that integrity_modsig_verify() can use it. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-08-06ima: Add modsig appraise_type option for module-style appended signaturesThiago Jung Bauermann1-0/+10
Introduce the modsig keyword to the IMA policy syntax to specify that a given hook should expect the file to have the IMA signature appended to it. Here is how it can be used in a rule: appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig With this rule, IMA will accept either a signature stored in the extended attribute or an appended signature. For now, the rule above will behave exactly the same as if appraise_type=imasig was specified. The actual modsig implementation will be introduced separately. 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>
2019-07-09Merge branch 'next-integrity' of ↵Linus Torvalds1-1/+2
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
2019-06-14x86/ima: fix the Kconfig dependency for IMA_ARCH_POLICYNayna Jain1-1/+2
If enabled, ima arch specific policies always adds the measurements rules, this makes it dependent on CONFIG_IMA. CONFIG_IMA_APPRAISE implicitly takes care of this, however it is needed explicitly for CONFIG_KEXEC_VERIFY_SIG. This patch adds the CONFIG_IMA dependency in combination with CONFIG_KEXEC_VERIFY_SIG for CONFIG_IMA_ARCH_POLICY Fixes: d958083a8f640 (x86/ima: define arch_get_ima_policy() for x86) Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Dave Young <dyoung@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner1-0/+1
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-11x86/ima: define arch_get_ima_policy() for x86Eric Richter1-1/+9
On x86, there are two methods of verifying a kexec'ed kernel image signature being loaded via the kexec_file_load syscall - an architecture specific implementaton or a IMA KEXEC_KERNEL_CHECK appraisal rule. Neither of these methods verify the kexec'ed kernel image signature being loaded via the kexec_load syscall. Secure boot enabled systems require kexec images to be signed. Therefore, this patch loads an IMA KEXEC_KERNEL_CHECK policy rule on secure boot enabled systems not configured with CONFIG_KEXEC_VERIFY_SIG enabled. When IMA_APPRAISE_BOOTPARAM is configured, different IMA appraise modes (eg. fix, log) can be specified on the boot command line, allowing unsigned or invalidly signed kernel images to be kexec'ed. This patch permits enabling IMA_APPRAISE_BOOTPARAM or IMA_ARCH_POLICY, but not both. Signed-off-by: Eric Richter <erichte@linux.ibm.com> Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Cc: David Howells <dhowells@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Peter Jones <pjones@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Young <dyoung@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-07-18ima: Do not audit if CONFIG_INTEGRITY_AUDIT is not setStefan Berger1-0/+1
If Integrity is not auditing, IMA shouldn't audit, either. Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-07-16ima: add build time policyMimi Zohar1-0/+58
IMA by default does not measure, appraise or audit files, but can be enabled at runtime by specifying a builtin policy on the boot command line or by loading a custom policy. This patch defines a build time policy, which verifies kernel modules, firmware, kexec image, and/or the IMA policy signatures. This build time policy is automatically enabled at runtime and persists after loading a custom policy. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-03-25ima: Fix Kconfig to select TPM 2.0 CRB interfaceJiandi An1-0/+1
TPM_CRB driver provides TPM CRB 2.0 support. If it is built as a module, the TPM chip is registered after IMA init. tpm_pcr_read() in IMA fails and displays the following message even though eventually there is a TPM chip on the system. ima: No TPM chip found, activating TPM-bypass! (rc=-19) Fix IMA Kconfig to select TPM_CRB so TPM_CRB driver is built in the kernel and initializes before IMA. Signed-off-by: Jiandi An <anjiandi@codeaurora.org> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-06-21IMA: Correct Kconfig dependencies for hash selectionBen Hutchings1-4/+4
IMA uses the hash algorithm too early to be able to use a module. Require the selected hash algorithm to be built-in. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2017-06-21ima: define Kconfig IMA_APPRAISE_BOOTPARAM optionMimi Zohar1-0/+8
Permit enabling the different "ima_appraise=" modes (eg. log, fix) from the boot command line. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2016-12-20ima: maintain memory size needed for serializing the measurement listMimi Zohar1-0/+12
In preparation for serializing the binary_runtime_measurements, this patch maintains the amount of memory required. Link: http://lkml.kernel.org/r/1480554346-29071-5-git-send-email-zohar@linux.vnet.ibm.com Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Andreas Steffen <andreas.steffen@strongswan.org> Cc: Josh Sklar <sklar@linux.vnet.ibm.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Stewart Smith <stewart@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-12IMA: Use the the system trusted keyrings instead of .ima_mokDavid Howells1-13/+23
Add a config option (IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY) that, when enabled, allows keys to be added to the IMA keyrings by userspace - with the restriction that each must be signed by a key in the system trusted keyrings. EPERM will be returned if this option is disabled, ENOKEY will be returned if no authoritative key can be found and EKEYREJECTED will be returned if the signature doesn't match. Other errors such as ENOPKG may also be returned. If this new option is enabled, the builtin system keyring is searched, as is the secondary system keyring if that is also enabled. Intermediate keys between the builtin system keyring and the key being added can be added to the secondary keyring (which replaces .ima_mok) to form a trust chain - provided they are also validly signed by a key in one of the trusted keyrings. The .ima_mok keyring is then removed and the IMA blacklist keyring gets its own config option (IMA_BLACKLIST_KEYRING). Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15IMA: allow reading back the current IMA policyPetko Manolov1-0/+10
It is often useful to be able to read back the IMA policy. It is even more important after introducing CONFIG_IMA_WRITE_POLICY. This option allows the root user to see the current policy rules. Signed-off-by: Zbigniew Jasinski <z.jasinski@samsung.com> Signed-off-by: Petko Manolov <petkan@mip-labs.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15IMA: create machine owner and blacklist keyringsPetko Manolov1-0/+18
This option creates IMA MOK and blacklist keyrings. IMA MOK is an intermediate keyring that sits between .system and .ima keyrings, effectively forming a simple CA hierarchy. To successfully import a key into .ima_mok it must be signed by a key which CA is in .system keyring. On turn any key that needs to go in .ima keyring must be signed by CA in either .system or .ima_mok keyrings. IMA MOK is empty at kernel boot. IMA blacklist keyring contains all revoked IMA keys. It is consulted before any other keyring. If the search is successful the requested operation is rejected and error is returned to the caller. Signed-off-by: Petko Manolov <petkan@mip-labs.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-12-15IMA: policy can now be updated multiple timesPetko Manolov1-0/+11
The new rules get appended to the original policy, forming a queue. The new rules are first added to a temporary list, which on error get released without disturbing the normal IMA operations. On success both lists (the current policy and the new rules) are spliced. IMA policy reads are many orders of magnitude more numerous compared to writes, the match code is RCU protected. The updater side also does list splice in RCU manner. Signed-off-by: Petko Manolov <petkan@mip-labs.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-11-23integrity: define '.evm' as a builtin 'trusted' keyringDmitry Kasatkin1-1/+4
Require all keys added to the EVM keyring be signed by an existing trusted key on the system trusted keyring. This patch also switches IMA to use integrity_init_keyring(). Changes in v3: * Added 'init_keyring' config based variable to skip initializing keyring instead of using __integrity_init_keyring() wrapper. * Added dependency back to CONFIG_IMA_TRUSTED_KEYRING Changes in v2: * Replace CONFIG_EVM_TRUSTED_KEYRING with IMA and EVM common CONFIG_INTEGRITY_TRUSTED_KEYRING configuration option * Deprecate CONFIG_IMA_TRUSTED_KEYRING but keep it for config file compatibility. (Mimi Zohar) Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2015-02-02ima: /proc/keys is now mandatoryDavid Howells1-1/+0
/proc/keys is now mandatory and its config option no longer exists, so it doesn't need selecting. Reported-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2014-12-07ima: Fix build failure on powerpc when TCG_IBMVTPM dependencies are not metMichael Ellerman1-1/+1
On powerpc we can end up with IMA=y and PPC_PSERIES=n which leads to: warning: (IMA) selects TCG_IBMVTPM which has unmet direct dependencies (TCG_TPM && PPC_PSERIES) tpm_ibmvtpm.c:(.text+0x14f3e8): undefined reference to `.plpar_hcall_norets' I'm not sure why IMA needs to select those user-visible symbols, but if it must then the simplest fix is to just express the proper dependencies on the select. Tested-by: Hon Ching (Vicky) Lo <lo1@us.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-11-18ima: require signature based appraisalDmitry Kasatkin1-0/+7
This patch provides CONFIG_IMA_APPRAISE_SIGNED_INIT kernel configuration option to force IMA appraisal using signatures. This is useful, when EVM key is not initialized yet and we want securely initialize integrity or any other functionality. It forces embedded policy to require signature. Signed initialization script can initialize EVM key, update the IMA policy and change further requirement of everything to be signed. Changes in v3: * kernel parameter fixed to configuration option in the patch description Changes in v2: * policy change of this patch separated from the key loading patch Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-11-18ima: load x509 certificate from the kernelDmitry Kasatkin1-0/+18
Define configuration option to load X509 certificate into the IMA trusted kernel keyring. It implements ima_load_x509() hook to load X509 certificate into the .ima trusted kernel keyring from the root filesystem. Changes in v3: * use ima_policy_flag in ima_get_action() ima_load_x509 temporarily clears ima_policy_flag to disable appraisal to load key. Use it to skip appraisal rules. * Key directory path changed to /etc/keys (Mimi) * Expand IMA_LOAD_X509 Kconfig help Changes in v2: * added '__init' * use ima_policy_flag to disable appraisal to load keys Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-09-09integrity: base integrity subsystem kconfig options on integrityDmitry Kasatkin1-2/+0
The integrity subsystem has lots of options and takes more than half of the security menu. This patch consolidates the options under "integrity", which are hidden if not enabled. This change does not affect existing configurations. Re-configuration is not needed. Changes v4: - no need to change "integrity subsystem" to menuconfig as options are hidden, when not enabled. (Mimi) - add INTEGRITY Kconfig help description Changes v3: - dependency to INTEGRITY removed when behind 'if INTEGRITY' Changes v2: - previous patch moved integrity out of the 'security' menu. This version keeps integrity as a security option (Mimi). Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2014-07-17ima: define '.ima' as a builtin 'trusted' keyringMimi Zohar1-0/+10
Require all keys added to the IMA keyring be signed by an existing trusted key on the system trusted keyring. Changelog v6: - remove ifdef CONFIG_IMA_TRUSTED_KEYRING in C code - Dmitry - update Kconfig dependency and help - select KEYS_DEBUG_PROC_KEYS - Dmitry Changelog v5: - Move integrity_init_keyring() to init_ima() - Dmitry - reset keyring[id] on failure - Dmitry Changelog v1: - don't link IMA trusted keyring to user keyring Changelog: - define stub integrity_init_keyring() function (reported-by Fengguang Wu) - differentiate between regular and trusted keyring names. - replace printk with pr_info (D. Kasatkin) - only make the IMA keyring a trusted keyring (reported-by D. Kastatkin) - define stub integrity_init_keyring() definition based on CONFIG_INTEGRITY_SIGNATURE, not CONFIG_INTEGRITY_ASYMMETRIC_KEYS. (reported-by Jim Davis) Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Acked-by: David Howells <dhowells@redhat.com>
2013-11-24Revert "ima: define '_ima' as a builtin 'trusted' keyring"Linus Torvalds1-8/+0
This reverts commit 217091dd7a7a1bdac027ddb7c5a25f6ac0b8e241, which caused the following build error: security/integrity/digsig.c:70:5: error: redefinition of ‘integrity_init_keyring’ security/integrity/integrity.h:149:12: note: previous definition of ‘integrity_init_keyring’ w security/integrity/integrity.h:149:12: warning: ‘integrity_init_keyring’ defined but not used reported by Krzysztof Kolasa. Mimi says: "I made the classic mistake of requesting this patch to be upstreamed at the last second, rather than waiting until the next open window. At this point, the best course would probably be to revert the two commits and fix them for the next open window" Reported-by: Krzysztof Kolasa <kkolasa@winsoft.pl> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-01ima: define '_ima' as a builtin 'trusted' keyringMimi Zohar1-0/+8
Require all keys added to the IMA keyring be signed by an existing trusted key on the system trusted keyring. Changelog: - define stub integrity_init_keyring() function (reported-by Fengguang Wu) - differentiate between regular and trusted keyring names. - replace printk with pr_info (D. Kasatkin) Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
2013-11-01ima: extend the measurement list to include the file signatureMimi Zohar1-0/+3
This patch defines a new template called 'ima-sig', which includes the file signature in the template data, in addition to the file's digest and pathname. A template is composed of a set of fields. Associated with each field is an initialization and display function. This patch defines a new template field called 'sig', the initialization function ima_eventsig_init(), and the display function ima_show_template_sig(). This patch modifies the .field_init() function definition to include the 'security.ima' extended attribute and length. Changelog: - remove unused code (Dmitry Kasatkin) - avoid calling ima_write_template_field_data() unnecesarily (Roberto Sassu) - rename DATA_FMT_SIG to DATA_FMT_HEX - cleanup ima_eventsig_init() based on Roberto's comments Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
2013-10-27ima: enable support for larger default filedata hash algorithmsMimi Zohar1-0/+35
The IMA measurement list contains two hashes - a template data hash and a filedata hash. The template data hash is committed to the TPM, which is limited, by the TPM v1.2 specification, to 20 bytes. The filedata hash is defined as 20 bytes as well. Now that support for variable length measurement list templates was added, the filedata hash is not limited to 20 bytes. This patch adds Kconfig support for defining larger default filedata hash algorithms and replacing the builtin default with one specified on the kernel command line. <uapi/linux/hash_info.h> contains a list of hash algorithms. The Kconfig default hash algorithm is a subset of this list, but any hash algorithm included in the list can be specified at boot, using the 'ima_hash=' kernel command line option. Changelog v2: - update Kconfig Changelog: - support hashes that are configured - use generic HASH_ALGO_ definitions - add Kconfig support - hash_setup must be called only once (Dmitry) - removed trailing whitespaces (Roberto Sassu) Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>