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* IMA: Add KEY_CHECK func to measure keysLakshmi Ramasubramanian2019-12-121-1/+3
| | | | | | | | | | | Measure keys loaded onto any keyring. This patch defines a new IMA policy func namely KEY_CHECK to measure keys. Updated ima_match_rules() to check for KEY_CHECK and ima_parse_rule() to handle KEY_CHECK. Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* ima: Check against blacklisted hashes for files with modsigNayna Jain2019-11-121-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Asymmetric private keys are used to sign multiple files. The kernel currently supports checking against blacklisted keys. However, if the public key is blacklisted, any file signed by the blacklisted key will automatically fail signature verification. Blacklisting the public key is not fine enough granularity, as we might want to only blacklist a particular file. This patch adds support for checking against the blacklisted hash of the file, without the appended signature, based on the IMA policy. It defines a new policy option "appraise_flag=check_blacklist". In addition to the blacklisted binary hashes stored in the firmware "dbx" variable, the Linux kernel may be configured to load blacklisted binary hashes onto the .blacklist keyring as well. The following example shows how to blacklist a specific kernel module hash. $ sha256sum kernel/kheaders.ko 77fa889b35a05338ec52e51591c1b89d4c8d1c99a21251d7c22b1a8642a6bad3 kernel/kheaders.ko $ grep BLACKLIST .config CONFIG_SYSTEM_BLACKLIST_KEYRING=y CONFIG_SYSTEM_BLACKLIST_HASH_LIST="blacklist-hash-list" $ cat certs/blacklist-hash-list "bin:77fa889b35a05338ec52e51591c1b89d4c8d1c99a21251d7c22b1a8642a6bad3" Update the IMA custom measurement and appraisal policy rules (/etc/ima-policy): measure func=MODULE_CHECK template=ima-modsig appraise func=MODULE_CHECK appraise_flag=check_blacklist appraise_type=imasig|modsig After building, installing, and rebooting the kernel: 545660333 ---lswrv 0 0 \_ blacklist: bin:77fa889b35a05338ec52e51591c1b89d4c8d1c99a21251d7c22b1a8642a6bad3 measure func=MODULE_CHECK template=ima-modsig appraise func=MODULE_CHECK appraise_flag=check_blacklist appraise_type=imasig|modsig modprobe: ERROR: could not insert 'kheaders': Permission denied 10 0c9834db5a0182c1fb0cdc5d3adcf11a11fd83dd ima-sig sha256:3bc6ed4f0b4d6e31bc1dbc9ef844605abc7afdc6d81a57d77a1ec9407997c40 2 /usr/lib/modules/5.4.0-rc3+/kernel/kernel/kheaders.ko 10 82aad2bcc3fa8ed94762356b5c14838f3bcfa6a0 ima-modsig sha256:3bc6ed4f0b4d6e31bc1dbc9ef844605abc7afdc6d81a57d77a1ec9407997c40 2 /usr/lib/modules/5.4.0rc3+/kernel/kernel/kheaders.ko sha256:77fa889b3 5a05338ec52e51591c1b89d4c8d1c99a21251d7c22b1a8642a6bad3 3082029a06092a864886f70d010702a082028b30820287020101310d300b0609608648 016503040201300b06092a864886f70d01070131820264.... 10 25b72217cc1152b44b134ce2cd68f12dfb71acb3 ima-buf sha256:8b58427fedcf8f4b20bc8dc007f2e232bf7285d7b93a66476321f9c2a3aa132 b blacklisted-hash 77fa889b35a05338ec52e51591c1b89d4c8d1c99a21251d7c22b1a8642a6bad3 Signed-off-by: Nayna Jain <nayna@linux.ibm.com> [zohar@linux.ibm.com: updated patch description] Signed-off-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/1572492694-6520-8-git-send-email-zohar@linux.ibm.com
* Merge branch 'next-lockdown' of ↵Linus Torvalds2019-09-281-0/+50
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * kexec: Allow kexec_file() with appropriate IMA policy when locked downMatthew Garrett2019-08-191-0/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Systems in lockdown mode should block the kexec of untrusted kernels. For x86 and ARM we can ensure that a kernel is trustworthy by validating a PE signature, but this isn't possible on other architectures. On those platforms we can use IMA digital signatures instead. Add a function to determine whether IMA has or will verify signatures for a given event type, and if so permit kexec_file() even if the kernel is otherwise locked down. This is restricted to cases where CONFIG_INTEGRITY_TRUSTED_KEYRING is set in order to prevent an attacker from loading additional keys at runtime. Signed-off-by: Matthew Garrett <mjg59@google.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> Cc: linux-integrity@vger.kernel.org Signed-off-by: James Morris <jmorris@namei.org>
* | ima: Define ima-modsig templateThiago Jung Bauermann2019-08-051-0/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | ima: Implement support for module-style appended signaturesThiago Jung Bauermann2019-08-051-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | ima: Add modsig appraise_type option for module-style appended signaturesThiago Jung Bauermann2019-08-051-2/+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>
* | ima: initialize the "template" field with the default templateMimi Zohar2019-08-011-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | IMA policy rules are walked sequentially. Depending on the ordering of the policy rules, the "template" field might be defined in one rule, but will be replaced by subsequent, applicable rules, even if the rule does not explicitly define the "template" field. This patch initializes the "template" once and only replaces the "template", when explicitly defined. Fixes: 19453ce0bcfb ("IMA: support for per policy rule template formats") Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* | Merge branch 'next-integrity' of ↵Linus Torvalds2019-07-081-23/+140
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * IMA: Define a new hook to measure the kexec boot command line argumentsPrakhar Srivastava2019-06-241-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently during soft reboot(kexec_file_load) boot command line arguments are not measured. Define hooks needed to measure kexec command line arguments during soft reboot(kexec_file_load). - A new ima hook ima_kexec_cmdline is defined to be called by the kexec code. - A new function process_buffer_measurement is defined to measure the buffer hash into the IMA measurement list. - A new func policy KEXEC_CMDLINE is defined to control the measurement. Signed-off-by: Prakhar Srivastava <prsriva02@gmail.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * IMA: support for per policy rule template formatsMatthew Garrett2019-06-191-2/+36
| | | | | | | | | | | | | | | | | | | | Admins may wish to log different measurements using different IMA templates. Add support for overriding the default template on a per-rule basis. Inspired-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * ima: use the lsm policy update notifierJanne Karhunen2019-06-141-20/+96
| | | | | | | | | | | | | | | | | | | | Don't do lazy policy updates while running the rule matching, run the updates as they happen. Depends on commit f242064c5df3 ("LSM: switch to blocking policy update notifiers") Signed-off-by: Janne Karhunen <janne.karhunen@gmail.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| * ima: Make arch_policy_entry staticYueHaibing2019-06-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Fix sparse warning: security/integrity/ima/ima_policy.c:202:23: warning: symbol 'arch_policy_entry' was not declared. Should it be static? Fixes: 6191706246de ("ima: add support for arch specific policies") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: YueHaibing <yuehaibing@huawei.com> Cc: stable@vger.kernel.org (linux-5.0) Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* | treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441Thomas Gleixner2019-06-051-5/+1
|/ | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation version 2 of the license extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 315 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ima: show rules with IMA_INMASK correctlyRoberto Sassu2019-05-291-9/+12
| | | | | | | | | Show the '^' character when a policy rule has flag IMA_INMASK. Fixes: 80eae209d63ac ("IMA: allow reading back the current IMA policy") Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* ima: fix wrong signed policy requirement when not appraisingPetr Vorel2019-05-191-3/+4
| | | | | | | | | | | | Kernel booted just with ima_policy=tcb (not with ima_policy=appraise_tcb) shouldn't require signed policy. Regression found with LTP test ima_policy.sh. Fixes: c52657d93b05 ("ima: refactor ima_init_policy()") Cc: stable@vger.kernel.org (linux-5.0) Signed-off-by: Petr Vorel <pvorel@suse.cz> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* Merge tag 'audit-pr-20190305' of ↵Linus Torvalds2019-03-071-4/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit updates from Paul Moore: "A lucky 13 audit patches for v5.1. Despite the rather large diffstat, most of the changes are from two bug fix patches that move code from one Kconfig option to another. Beyond that bit of churn, the remaining changes are largely cleanups and bug-fixes as we slowly march towards container auditing. It isn't all boring though, we do have a couple of new things: file capabilities v3 support, and expanded support for filtering on filesystems to solve problems with remote filesystems. All changes pass the audit-testsuite. Please merge for v5.1" * tag 'audit-pr-20190305' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: audit: mark expected switch fall-through audit: hide auditsc_get_stamp and audit_serial prototypes audit: join tty records to their syscall audit: remove audit_context when CONFIG_ AUDIT and not AUDITSYSCALL audit: remove unused actx param from audit_rule_match audit: ignore fcaps on umount audit: clean up AUDITSYSCALL prototypes and stubs audit: more filter PATH records keyed on filesystem magic audit: add support for fcaps v3 audit: move loginuid and sessionid from CONFIG_AUDITSYSCALL to CONFIG_AUDIT audit: add syscall information to CONFIG_CHANGE records audit: hand taken context to audit_kill_trees for syscall logging audit: give a clue what CONFIG_CHANGE op was involved
| * audit: remove unused actx param from audit_rule_matchRichard Guy Briggs2019-01-311-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The audit_rule_match() struct audit_context *actx parameter is not used by any in-tree consumers (selinux, apparmour, integrity, smack). The audit context is an internal audit structure that should only be accessed by audit accessor functions. It was part of commit 03d37d25e0f9 ("LSM/Audit: Introduce generic Audit LSM hooks") but appears to have never been used. Remove it. Please see the github issue https://github.com/linux-audit/audit-kernel/issues/107 Signed-off-by: Richard Guy Briggs <rgb@redhat.com> [PM: fixed the referenced commit title] Signed-off-by: Paul Moore <paul@paul-moore.com>
* | security: mark expected switch fall-throughs and add a missing breakGustavo A. R. Silva2019-02-221-0/+4
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. This patch fixes the following warnings: security/integrity/ima/ima_template_lib.c:85:10: warning: this statement may fall through [-Wimplicit-fallthrough=] security/integrity/ima/ima_policy.c:940:18: warning: this statement may fall through [-Wimplicit-fallthrough=] security/integrity/ima/ima_policy.c:943:7: warning: this statement may fall through [-Wimplicit-fallthrough=] security/integrity/ima/ima_policy.c:972:21: warning: this statement may fall through [-Wimplicit-fallthrough=] security/integrity/ima/ima_policy.c:974:7: warning: this statement may fall through [-Wimplicit-fallthrough=] security/smack/smack_lsm.c:3391:9: warning: this statement may fall through [-Wimplicit-fallthrough=] security/apparmor/domain.c:569:6: warning: this statement may fall through [-Wimplicit-fallthrough=] Warning level 3 was used: -Wimplicit-fallthrough=3 Also, add a missing break statement to fix the following warning: security/integrity/ima/ima_appraise.c:116:26: warning: this statement may fall through [-Wimplicit-fallthrough=] Acked-by: John Johansen <john.johansen@canonical.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: James Morris <james.morris@microsoft.com>
* Merge branch 'next-integrity' of ↵Linus Torvalds2019-01-021-43/+128
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
| * Merge branch 'next-integrity' of ↵James Morris2018-12-171-43/+128
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity into next-integrity From Mimi: 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 pull request 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.)
| | * ima: don't measure/appraise files on efivarfsMimi Zohar2018-12-111-1/+3
| | | | | | | | | | | | | | | | | | | | | Update the builtin IMA policies specified on the boot command line (eg. ima_policy="tcb|appraise_tcb") to permit accessing efivar files. Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| | * ima: add support for arch specific policiesNayna Jain2018-12-111-2/+70
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Builtin IMA policies can be enabled on the boot command line, and replaced with a custom policy, normally during early boot in the initramfs. Build time IMA policy rules were recently added. These rules are automatically enabled on boot and persist after loading a custom policy. There is a need for yet another type of policy, an architecture specific policy, which is derived at runtime during kernel boot, based on the runtime secure boot flags. Like the build time policy rules, these rules persist after loading a custom policy. This patch adds support for loading an architecture specific IMA policy. Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Co-Developed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
| | * ima: refactor ima_init_policy()Nayna Jain2018-12-111-41/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes the code duplication in ima_init_policy() by defining a new function named add_rules(). The new function adds the rules to the initial IMA policy, the custom policy or both based on the policy mask (IMA_DEFAULT_POLICY, IMA_CUSTOM_POLICY). Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
* | | Merge branch 'next-general' of ↵Linus Torvalds2018-12-271-1/+1
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull general security subsystem updates from James Morris: "The main changes here are Paul Gortmaker's removal of unneccesary module.h infrastructure" * 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: security: integrity: partial revert of make ima_main explicitly non-modular security: fs: make inode explicitly non-modular security: audit and remove any unnecessary uses of module.h security: integrity: make evm_main explicitly non-modular keys: remove needless modular infrastructure from ecryptfs_format security: integrity: make ima_main explicitly non-modular tomoyo: fix small typo
| * | security: audit and remove any unnecessary uses of module.hPaul Gortmaker2018-12-121-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Historically a lot of these existed because we did not have a distinction between what was modular code and what was providing support to modules via EXPORT_SYMBOL and friends. That changed when we forked out support for the latter into the export.h file. This means we should be able to reduce the usage of module.h in code that is obj-y Makefile or bool Kconfig. The advantage in removing such instances is that module.h itself sources about 15 other headers; adding significantly to what we feed cpp, and it can obscure what headers we are effectively using. Since module.h might have been the implicit source for init.h (for __init) and for export.h (for EXPORT_SYMBOL) we consider each instance for the presence of either and replace as needed. Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: John Johansen <john.johansen@canonical.com> Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: linux-security-module@vger.kernel.org Cc: linux-integrity@vger.kernel.org Cc: keyrings@vger.kernel.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: James Morris <james.morris@microsoft.com>
* / ima: cleanup the match_token policy codeMimi Zohar2018-12-171-5/+5
|/ | | | | | | | Start the policy_tokens and the associated enumeration from zero, simplifying the pt macro. Signed-off-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ima: Differentiate auditing policy rules from "audit" actionsStefan Berger2018-07-181-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | The AUDIT_INTEGRITY_RULE is used for auditing IMA policy rules and the IMA "audit" policy action. This patch defines AUDIT_INTEGRITY_POLICY_RULE to reflect the IMA policy rules. Since we defined a new message type we can now also pass the audit_context and get an associated SYSCALL record. This now produces the following records when parsing IMA policy's rules: type=UNKNOWN[1807] msg=audit(1527888965.738:320): action=audit \ func=MMAP_CHECK mask=MAY_EXEC res=1 type=UNKNOWN[1807] msg=audit(1527888965.738:320): action=audit \ func=FILE_CHECK mask=MAY_READ res=1 type=SYSCALL msg=audit(1527888965.738:320): arch=c000003e syscall=1 \ success=yes exit=17 a0=1 a1=55bcfcca9030 a2=11 a3=7fcc1b55fb38 \ items=0 ppid=1567 pid=1601 auid=0 uid=0 gid=0 euid=0 suid=0 \ fsuid=0 egid=0 sgid=0 fsgid=0 tty=tty2 ses=2 comm="echo" \ exe="/usr/bin/echo" \ subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null) 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>
* ima: Do not audit if CONFIG_INTEGRITY_AUDIT is not setStefan Berger2018-07-181-1/+5
| | | | | | | | 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>
* ima: Use audit_log_format() rather than audit_log_string()Stefan Berger2018-07-181-2/+1
| | | | | | | | | | Remove the usage of audit_log_string() and replace it with audit_log_format(). Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Suggested-by: Steve Grubb <sgrubb@redhat.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: Call audit_log_string() rather than logging it untrustedStefan Berger2018-07-181-1/+1
| | | | | | | | | | | The parameters passed to this logging function are all provided by a privileged user and therefore we can call audit_log_string() rather than audit_log_untrustedstring(). Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Suggested-by: Steve Grubb <sgrubb@redhat.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: add build time policyMimi Zohar2018-07-161-3/+43
| | | | | | | | | | | | | | | 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>
* ima: based on policy require signed kexec kernel imagesMimi Zohar2018-07-161-0/+2
| | | | | | | | | | | | The original kexec_load syscall can not verify file signatures, nor can the kexec image be measured. Based on policy, deny the kexec_load syscall. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.morris@microsoft.com>
* IMA: use list_splice_tail_init_rcu() instead of its open coded variantPetko Manolov2018-05-311-15/+2
| | | | | | | | Use list_splice_tail_init_rcu() to extend the existing custom IMA policy with additional IMA policy rules. Signed-off-by: Petko Manolov <petko.manolov@konsulko.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: fix updating the ima_appraise flagMimi Zohar2018-05-221-9/+19
| | | | | | | | | | | | | | | As IMA policy rules are added, a mask of the type of rule (eg. kernel modules, firmware, IMA policy) is updated. Unlike custom IMA policy rules, which replace the original builtin policy rules and update the mask, the builtin "secure_boot" policy rules were loaded, but did not update the mask. This patch refactors the code to load custom policies, defining a new function named ima_appraise_flag(). The new function is called either when loading the builtin "secure_boot" or custom policies. Fixes: 503ceaef8e2e ("ima: define a set of appraisal rules requiring file signatures") Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: define a new policy condition based on the filesystem nameMimi Zohar2018-05-221-1/+24
| | | | | | | | | | | | | | | | | | | | | | If/when file data signatures are distributed with the file data, this patch will not be needed. In the current environment where only some files are signed, the ability to differentiate between file systems is needed. Some file systems consider the file system magic number internal to the file system. This patch defines a new IMA policy condition named "fsname", based on the superblock's file_system_type (sb->s_type) name. This allows policy rules to be expressed in terms of the filesystem name. The following sample rules require file signatures on rootfs files executed or mmap'ed. appraise func=BPRM_CHECK fsname=rootfs appraise_type=imasig appraise func=FILE_MMAP fsname=rootfs appraise_type=imasig Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Theodore Ts'o <tytso@mit.edu>
* ima: Add smackfs to the default appraise/measure listMartin Townsend2018-03-251-0/+2
| | | | | | | | | This is required to use SMACK and IMA/EVM together. Add it to the default nomeasure/noappraise list like other pseudo filesystems. Signed-off-by: Martin Townsend <mtownsend1973@gmail.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: fail signature verification based on policyMimi Zohar2018-03-231-0/+5
| | | | | | | | | | | | | | | | | | This patch addresses the fuse privileged mounted filesystems in environments which are unwilling to accept the risk of trusting the signature verification and want to always fail safe, but are for example using a pre-built kernel. This patch defines a new builtin policy named "fail_securely", which can be specified on the boot command line as an argument to "ima_policy=". Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Seth Forshee <seth.forshee@canonical.com> Cc: Dongsu Park <dongsu@kinvolk.io> Cc: Alban Crequy <alban@kinvolk.io> Acked-by: Serge Hallyn <serge@hallyn.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
* ima: clear IMA_HASHMimi Zohar2018-03-231-1/+1
| | | | | | | The IMA_APPRAISE and IMA_HASH policies overlap. Clear IMA_HASH properly. Fixes: da1b0029f527 ("ima: support new "hash" and "dont_hash" policy actions") Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* IMA: Support using new creds in appraisal policyMatthew Garrett2018-03-231-8/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The existing BPRM_CHECK functionality in IMA validates against the credentials of the existing process, not any new credentials that the child process may transition to. Add an additional CREDS_CHECK target and refactor IMA to pass the appropriate creds structure. In ima_bprm_check(), check with both the existing process credentials and the credentials that will be committed when the new process is started. This will not change behaviour unless the system policy is extended to include CREDS_CHECK targets - BPRM_CHECK will continue to check the same credentials that it did previously. After this patch, an IMA policy rule along the lines of: measure func=CREDS_CHECK subj_type=unconfined_t will trigger if a process is executed and runs as unconfined_t, ignoring the context of the parent process. This is in contrast to: measure func=BPRM_CHECK subj_type=unconfined_t which will trigger if the process that calls exec() is already executing in unconfined_t, ignoring the context that the child process executes into. Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Changelog: - initialize ima_creds_status
* ima/policy: fix parsing of fsuuidMike Rapoport2018-01-181-1/+1
| | | | | | | | | | | | | The switch to uuid_t invereted the logic of verfication that &entry->fsuuid is zero during parsing of "fsuuid=" rule. Instead of making sure the &entry->fsuuid field is not attempted to be overwritten, we bail out for perfectly correct rule. Fixes: 787d8c530af7 ("ima/policy: switch to use uuid_t") Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* ima: support new "hash" and "dont_hash" policy actionsMimi Zohar2017-12-181-2/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | The builtin ima_appraise_tcb policy, which is specified on the boot command line, can be replaced with a custom policy, normally early in the boot process. Custom policies can be more restrictive in some ways, like requiring file signatures, but can be less restrictive in other ways, like not appraising mutable files. With a less restrictive policy in place, files in the builtin policy might not be hashed and labeled with a security.ima hash. On reboot, files which should be labeled in the ima_appraise_tcb are not labeled, possibly preventing the system from booting properly. To resolve this problem, this patch extends the existing IMA policy actions "measure", "dont_measure", "appraise", "dont_appraise", and "audit" with "hash" and "dont_hash". The new "hash" action will write the file hash as security.ima, but without requiring the file to be appraised as well. For example, the builtin ima_appraise_tcb policy includes the rule, "appraise fowner=0". Adding the "hash fowner=0" rule to a custom policy, will cause the needed file hashes to be calculated and written as security.ima xattrs. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
* ima: Fix bool initialization/comparisonThomas Meyer2017-11-081-3/+3
| | | | | | | | Bool initializations should use true and false. Bool tests don't need comparisons. Signed-off-by: Thomas Meyer <thomas@m3y3r.de> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* Merge branch 'next' of ↵Linus Torvalds2017-07-051-60/+46
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security layer updates from James Morris: - a major update for AppArmor. From JJ: * several bug fixes and cleanups * the patch to add symlink support to securityfs that was floated on the list earlier and the apparmorfs changes that make use of securityfs symlinks * it introduces the domain labeling base code that Ubuntu has been carrying for several years, with several cleanups applied. And it converts the current mediation over to using the domain labeling base, which brings domain stacking support with it. This finally will bring the base upstream code in line with Ubuntu and provide a base to upstream the new feature work that Ubuntu carries. * This does _not_ contain any of the newer apparmor mediation features/controls (mount, signals, network, keys, ...) that Ubuntu is currently carrying, all of which will be RFC'd on top of this. - Notable also is the Infiniband work in SELinux, and the new file:map permission. From Paul: "While we're down to 21 patches for v4.13 (it was 31 for v4.12), the diffstat jumps up tremendously with over 2k of line changes. Almost all of these changes are the SELinux/IB work done by Daniel Jurgens; some other noteworthy changes include a NFS v4.2 labeling fix, a new file:map permission, and reporting of policy capabilities on policy load" There's also now genfscon labeling support for tracefs, which was lost in v4.1 with the separation from debugfs. - Smack incorporates a safer socket check in file_receive, and adds a cap_capable call in privilege check. - TPM as usual has a bunch of fixes and enhancements. - Multiple calls to security_add_hooks() can now be made for the same LSM, to allow LSMs to have hook declarations across multiple files. - IMA now supports different "ima_appraise=" modes (eg. log, fix) from the boot command line. * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (126 commits) apparmor: put back designators in struct initialisers seccomp: Switch from atomic_t to recount_t seccomp: Adjust selftests to avoid double-join seccomp: Clean up core dump logic IMA: update IMA policy documentation to include pcr= option ima: Log the same audit cause whenever a file has no signature ima: Simplify policy_func_show. integrity: Small code improvements ima: fix get_binary_runtime_size() ima: use ima_parse_buf() to parse template data ima: use ima_parse_buf() to parse measurements headers ima: introduce ima_parse_buf() ima: Add cgroups2 to the defaults list ima: use memdup_user_nul ima: fix up #endif comments IMA: Correct Kconfig dependencies for hash selection ima: define is_ima_appraise_enabled() ima: define Kconfig IMA_APPRAISE_BOOTPARAM option ima: define a set of appraisal rules requiring file signatures ima: extend the "ima_policy" boot command line to support multiple policies ...
| * ima: Simplify policy_func_show.Thiago Jung Bauermann2017-06-211-52/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the func_tokens array uses the same indices as enum ima_hooks, policy_func_show can be a lot simpler, and the func_* enum becomes unnecessary. Also, if we use the same macro trick used by kernel_read_file_id_str we can use one hooks list for both the enum and the string array, making sure they are always in sync (suggested by Mimi Zohar). Finally, by using the printf pattern for the function token directly instead of using the pt macro we can simplify policy_func_show even further and avoid needing a temporary buffer. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
| * integrity: Small code improvementsThiago Jung Bauermann2017-06-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These changes are too small to warrant their own patches: The keyid and sig_size members of struct signature_v2_hdr are in BE format, so use a type that makes this assumption explicit. Also, use beXX_to_cpu instead of __beXX_to_cpu to read them. Change integrity_kernel_read to take a void * buffer instead of char * buffer, so that callers don't have to use a cast if they provide a buffer that isn't a char *. Add missing #endif comment in ima.h pointing out which macro it refers to. Add missing fall through comment in ima_appraise.c. Constify mask_tokens and func_tokens arrays. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
| * ima: Add cgroups2 to the defaults listLaura Abbott2017-06-211-0/+3
| | | | | | | | | | | | | | | | cgroups2 is beginning to show up in wider usage. Add it to the default nomeasure/noappraise list like other filesystems. Signed-off-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
| * ima: define a set of appraisal rules requiring file signaturesMimi Zohar2017-06-211-1/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The builtin "ima_appraise_tcb" policy should require file signatures for at least a few of the hooks (eg. kernel modules, firmware, and the kexec kernel image), but changing it would break the existing userspace/kernel ABI. This patch defines a new builtin policy named "secure_boot", which can be specified on the "ima_policy=" boot command line, independently or in conjunction with the "ima_appraise_tcb" policy, by specifing ima_policy="appraise_tcb | secure_boot". The new appraisal rules requiring file signatures will be added prior to the "ima_appraise_tcb" rules. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Changelog: - Reference secure boot in the new builtin policy name. (Thiago Bauermann)
| * ima: extend the "ima_policy" boot command line to support multiple policiesMimi Zohar2017-06-211-5/+10
| | | | | | | | | | | | | | Add support for providing multiple builtin policies on the "ima_policy=" boot command line. Use "|" as the delimitor separating the policy names. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
* | fs: switch ->s_uuid to uuid_tChristoph Hellwig2017-06-051-1/+1
| | | | | | | | | | | | | | | | | | | | For some file systems we still memcpy into it, but in various places this already allows us to use the proper uuid helpers. More to come.. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (Changes to IMA/EVM) Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-25 08:22:59 +0000