kernel.git/security/integrity/ima/ima.h, branch linux-5.4.y

ima: Rename internal filter rule functions

2023-01-18T10:41:01Z

[ Upstream commit b8867eedcf76caef8ae6412da97cd9abfd092ff8 ] Rename IMA's internal filter rule functions from security_filter_rule_*() to ima_filter_rule_*(). This avoids polluting the security_* namespace, which is typically reserved for general security subsystem infrastructure. Signed-off-by: Tyler Hicks Suggested-by: Casey Schaufler [zohar@linux.ibm.com: reword using the term "filter", not "audit"] Signed-off-by: Mimi Zohar Stable-dep-of: c7423dbdbc9e ("ima: Handle -ESTALE returned by ima_filter_rule_match()") Signed-off-by: Sasha Levin

ima: extend boot_aggregate with kernel measurements

2020-12-08T09:40:24Z

[ Upstream commit 20c59ce010f84300f6c655d32db2610d3433f85c ] Registers 8-9 are used to store measurements of the kernel and its command line (e.g., grub2 bootloader with tpm module enabled). IMA should include them in the boot aggregate. Registers 8-9 should be only included in non-SHA1 digests to avoid ambiguity. Signed-off-by: Maurizio Drocco Reviewed-by: Bruno Meneguele Tested-by: Bruno Meneguele (TPM 1.2, TPM 2.0) Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

ima: Have the LSM free its audit rule

2020-08-19T06:16:12Z

[ Upstream commit 9ff8a616dfab96a4fa0ddd36190907dc68886d9b ] Ask the LSM to free its audit rule rather than directly calling kfree(). Both AppArmor and SELinux do additional work in their audit_rule_free() hooks. Fix memory leaks by allowing the LSMs to perform necessary work. Fixes: b16942455193 ("ima: use the lsm policy update notifier") Signed-off-by: Tyler Hicks Cc: Janne Karhunen Cc: Casey Schaufler Reviewed-by: Mimi Zohar Signed-off-by: Mimi Zohar Signed-off-by: Sasha Levin

ima: Call ima_calc_boot_aggregate() in ima_eventdigest_init()

2020-06-22T07:31:15Z

commit 6cc7c266e5b47d3cd2b5bb7fd3aac4e6bb2dd1d2 upstream. If the template field 'd' is chosen and the digest to be added to the measurement entry was not calculated with SHA1 or MD5, it is recalculated with SHA1, by using the passed file descriptor. However, this cannot be done for boot_aggregate, because there is no file descriptor. This patch adds a call to ima_calc_boot_aggregate() in ima_eventdigest_init(), so that the digest can be recalculated also for the boot_aggregate entry. Cc: stable@vger.kernel.org # 3.13.x Fixes: 3ce1217d6cd5d ("ima: define template fields library and new helpers") Reported-by: Takashi Iwai Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

ima: Fix ima digest hash table key calculation

2020-06-22T07:31:14Z

commit 1129d31b55d509f15e72dc68e4b5c3a4d7b4da8d upstream. Function hash_long() accepts unsigned long, while currently only one byte is passed from ima_hash_key(), which calculates a key for ima_htable. Given that hashing the digest does not give clear benefits compared to using the digest itself, remove hash_long() and return the modulus calculated on the first two bytes of the digest with the number of slots. Also reduce the depth of the hash table by doubling the number of slots. Cc: stable@vger.kernel.org Fixes: 3323eec921ef ("integrity: IMA as an integrity service provider") Co-developed-by: Roberto Sassu Signed-off-by: Roberto Sassu Signed-off-by: Krzysztof Struczynski Acked-by: David.Laight@aculab.com (big endian system concerns) Signed-off-by: Mimi Zohar Signed-off-by: Greg Kroah-Hartman

Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

2019-09-28T15:14:15Z

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 down

2019-08-20T04:54:16Z

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 Acked-by: Mimi Zohar Cc: Dmitry Kasatkin Cc: linux-integrity@vger.kernel.org Signed-off-by: James Morris

ima: Store the measurement again when appraising a modsig

2019-08-05T22:40:26Z

If the IMA template contains the "modsig" or "d-modsig" field, then the modsig should be added to the measurement list when the file is appraised. And that is what normally happens, but if a measurement rule caused a file containing a modsig to be measured before a different rule causes it to be appraised, the resulting measurement entry will not contain the modsig because it is only fetched during appraisal. When the appraisal rule triggers, it won't store a new measurement containing the modsig because the file was already measured. We need to detect that situation and store an additional measurement with the modsig. This is done by adding an IMA_MEASURE action flag if we read a modsig and the IMA template contains a modsig field. Suggested-by: Mimi Zohar Signed-off-by: Thiago Jung Bauermann Signed-off-by: Mimi Zohar

ima: Define ima-modsig template

2019-08-05T22:40:25Z

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 Signed-off-by: Thiago Jung Bauermann Signed-off-by: Mimi Zohar

ima: Collect modsig

2019-08-05T22:40:24Z

Obtain the modsig and calculate its corresponding hash in ima_collect_measurement(). Signed-off-by: Thiago Jung Bauermann Signed-off-by: Mimi Zohar