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2018-12-17ima: cleanup the match_token policy codeMimi Zohar
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>
2018-12-17integrity: Remove references to module keyringThiago Jung Bauermann
From what I can tell, it has never been used. Mimi: This was introduced prior to Rusty's decision to use appended signatures for kernel modules. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-12-17Merge tag 'tpmdd-next-20181217' of ↵James Morris
git://git.infradead.org/users/jjs/linux-tpmdd into next-tpm tpmdd updates for Linux v4.21 From Jarkko: v4.21 updates: * Support for partial reads of /dev/tpm0. * Clean up for TPM 1.x code: move the commands to tpm1-cmd.c and make everything to use the same data structure for building TPM commands i.e. struct tpm_buf.
2018-12-17Merge branch 'next-integrity' of ↵James Morris
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.)
2018-12-17Merge tag 'v4.20-rc7' into next-generalJames Morris
Sync with Linux 4.20-rc7, to pick up: Revert "ovl: relax permission checking on underlying layers"
2018-12-12ima: Use inode_is_open_for_writeNikolay Borisov
Use the aptly named function rather than open coding the check. No functional changes. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-12-12ima: Support platform keyring for kernel appraisalNayna Jain
On secure boot enabled systems, the bootloader verifies the kernel image and possibly the initramfs signatures based on a set of keys. A soft reboot(kexec) of the system, with the same kernel image and initramfs, requires access to the original keys to verify the signatures. This patch allows IMA-appraisal access to those original keys, now loaded on the platform keyring, needed for verifying the kernel image and initramfs signatures. [zohar@linux.ibm.com: only use platform keyring if it's enabled (Thiago)] Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: James Morris <james.morris@microsoft.com> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-12-12efi: Allow the "db" UEFI variable to be suppressedJosh Boyer
If a user tells shim to not use the certs/hashes in the UEFI db variable for verification purposes, shim will set a UEFI variable called MokIgnoreDB. Have the uefi import code look for this and ignore the db variable if it is found. [zohar@linux.ibm.com: removed reference to "secondary" keyring comment] Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Nayna Jain <nayna@linux.ibm.com> Acked-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: James Morris <james.morris@microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-12-12efi: Import certificates from UEFI Secure BootJosh Boyer
Secure Boot stores a list of allowed certificates in the 'db' variable. This patch imports those certificates into the platform keyring. The shim UEFI bootloader has a similar certificate list stored in the 'MokListRT' variable. We import those as well. Secure Boot also maintains a list of disallowed certificates in the 'dbx' variable. We load those certificates into the system blacklist keyring and forbid any kernel signed with those from loading. [zohar@linux.ibm.com: dropped Josh's original patch description] Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-12-12efi: Add an EFI signature blob parserDave Howells
Add a function to parse an EFI signature blob looking for elements of interest. A list is made up of a series of sublists, where all the elements in a sublist are of the same type, but sublists can be of different types. For each sublist encountered, the function pointed to by the get_handler_for_guid argument is called with the type specifier GUID and returns either a pointer to a function to handle elements of that type or NULL if the type is not of interest. If the sublist is of interest, each element is passed to the handler function in turn. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-12-12integrity: Load certs to the platform keyringNayna Jain
The patch refactors integrity_load_x509(), making it a wrapper for a new function named integrity_add_key(). This patch also defines a new function named integrity_load_cert() for loading the platform keys. Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: James Morris <james.morris@microsoft.com> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-12-12integrity: Define a trusted platform keyringNayna Jain
On secure boot enabled systems, a verified kernel may need to kexec additional kernels. For example, it may be used as a bootloader needing to kexec a target kernel or it may need to kexec a crashdump kernel. In such cases, it may want to verify the signature of the next kernel image. It is further possible that the kernel image is signed with third party keys which are stored as platform or firmware keys in the 'db' variable. The kernel, however, can not directly verify these platform keys, and an administrator may therefore not want to trust them for arbitrary usage. In order to differentiate platform keys from other keys and provide the necessary separation of trust, the kernel needs an additional keyring to store platform keys. This patch creates the new keyring called ".platform" to isolate keys provided by platform from keys by kernel. These keys are used to facilitate signature verification during kexec. Since the scope of this keyring is only the platform/firmware keys, it cannot be updated from userspace. This keyring can be enabled by setting CONFIG_INTEGRITY_PLATFORM_KEYRING. Signed-off-by: Nayna Jain <nayna@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: James Morris <james.morris@microsoft.com> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-12-12security: audit and remove any unnecessary uses of module.hPaul Gortmaker
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>
2018-12-12security: integrity: make evm_main explicitly non-modularPaul Gortmaker
The Makefile/Kconfig entry controlling compilation of this code is: obj-$(CONFIG_EVM) += evm.o evm-y := evm_main.o evm_crypto.o evm_secfs.o security/integrity/evm/Kconfig:config EVM security/integrity/evm/Kconfig: bool "EVM support" ...meaning that it currently is not being built as a module by anyone. Lets remove the couple traces of modular infrastructure use, so that when reading the driver there is no doubt it is builtin-only. We also delete the MODULE_LICENSE tag etc. since all that information is already contained at the top of the file in the comments. Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: linux-ima-devel@lists.sourceforge.net Cc: linux-security-module@vger.kernel.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-12-12security: integrity: make ima_main explicitly non-modularPaul Gortmaker
The Makefile/Kconfig entry controlling compilation of this code is: obj-$(CONFIG_IMA) += ima.o ima-y := ima_fs.o ima_queue.o ima_init.o ima_main.o ima_crypto.o ima_api.o \ ima_policy.o ima_template.o ima_template_lib.o security/integrity/ima/Kconfig:config IMA security/integrity/ima/Kconfig- bool "Integrity Measurement Architecture(IMA)" ...meaning that it currently is not being built as a module by anyone. Lets remove the couple traces of modular infrastructure use, so that when reading the driver there is no doubt it is builtin-only. We also delete the MODULE_LICENSE tag etc. since all that information is already contained at the top of the file in the comments. Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: linux-ima-devel@lists.sourceforge.net Cc: linux-security-module@vger.kernel.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-12-11ima: don't measure/appraise files on efivarfsMimi Zohar
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>
2018-12-11x86/ima: define arch_get_ima_policy() for x86Eric Richter
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>
2018-12-11ima: add support for arch specific policiesNayna Jain
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>
2018-12-11ima: refactor ima_init_policy()Nayna Jain
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>
2018-12-11ima: prevent kexec_load syscall based on runtime secureboot flagNayna Jain
When CONFIG_KEXEC_VERIFY_SIG is enabled, the kexec_file_load syscall requires the kexec'd kernel image to be signed. Distros are concerned about totally disabling the kexec_load syscall. As a compromise, the kexec_load syscall will only be disabled when CONFIG_KEXEC_VERIFY_SIG is configured and the system is booted with secureboot enabled. This patch disables the kexec_load syscall only for systems booted with secureboot enabled. [zohar@linux.ibm.com: add missing mesage on kexec_load failure] 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>
2018-11-26audit: use current whenever possiblePaul Moore
There are many places, notably audit_log_task_info() and audit_log_exit(), that take task_struct pointers but in reality they are always working on the current task. This patch eliminates the task_struct arguments and uses current directly which allows a number of cleanups as well. Acked-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2018-11-20crypto: drop mask=CRYPTO_ALG_ASYNC from 'shash' tfm allocationsEric Biggers
'shash' algorithms are always synchronous, so passing CRYPTO_ALG_ASYNC in the mask to crypto_alloc_shash() has no effect. Many users therefore already don't pass it, but some still do. This inconsistency can cause confusion, especially since the way the 'mask' argument works is somewhat counterintuitive. Thus, just remove the unneeded CRYPTO_ALG_ASYNC flags. This patch shouldn't change any actual behavior. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-13integrity: support new struct public_key_signature encoding fieldMimi Zohar
On systems with IMA-appraisal enabled with a policy requiring file signatures, the "good" signature values are stored on the filesystem as extended attributes (security.ima). Signature verification failure would normally be limited to just a particular file (eg. executable), but during boot signature verification failure could result in a system hang. Defining and requiring a new public_key_signature field requires all callers of asymmetric signature verification to be updated to reflect the change. This patch updates the integrity asymmetric_verify() caller. Fixes: 82f94f24475c ("KEYS: Provide software public key query function [ver #2]") Signed-off-by: Mimi Zohar <zohar@linux.ibm.com> Cc: David Howells <dhowells@redhat.com> Acked-by: Denis Kenzior <denkenz@gmail.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-11-13integrity: support new struct public_key_signature encoding fieldMimi Zohar
On systems with IMA-appraisal enabled with a policy requiring file signatures, the "good" signature values are stored on the filesystem as extended attributes (security.ima). Signature verification failure would normally be limited to just a particular file (eg. executable), but during boot signature verification failure could result in a system hang. Defining and requiring a new public_key_signature field requires all callers of asymmetric signature verification to be updated to reflect the change. This patch updates the integrity asymmetric_verify() caller. Fixes: 82f94f24475c ("KEYS: Provide software public key query function [ver #2]") Signed-off-by: Mimi Zohar <zohar@linux.ibm.com> Cc: David Howells <dhowells@redhat.com> Acked-by: Denis Kenzior <denkenz@gmail.com>
2018-11-13tpm: use u32 instead of int for PCR indexTomas Winkler
The TPM specs defines PCR index as a positive number, and there is no reason to use a signed number. It is also a possible security issue as currently no functions check for a negative index, which may become a large number when converted to u32. Adjust the API to use u32 instead of int in all PCR related functions. Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-10-25Merge branch 'next-integrity' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull integrity updates from James Morris: "From Mimi: This contains a couple of bug fixes, including one for a recent problem with calculating file hashes on overlayfs, and some code cleanup" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: MAINTAINERS: add Jarkko as maintainer for trusted keys ima: open a new file instance if no read permissions ima: fix showing large 'violations' or 'runtime_measurements_count' security/integrity: remove unnecessary 'init_keyring' variable security/integrity: constify some read-only data vfs: require i_size <= SIZE_MAX in kernel_read_file()
2018-10-10LSM: Record LSM name in struct lsm_infoKees Cook
In preparation for making LSM selections outside of the LSMs, include the name of LSMs in struct lsm_info. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-10LSM: Convert security_initcall() into DEFINE_LSM()Kees Cook
Instead of using argument-based initializers, switch to defining the contents of struct lsm_info on a per-LSM basis. This also drops the final use of the now inaccurate "initcall" naming. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: James Morris <james.morris@microsoft.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-10LSM: Convert from initcall to struct lsm_infoKees Cook
In preparation for doing more interesting LSM init probing, this converts the existing initcall system into an explicit call into a function pointer from a section-collected struct lsm_info array. Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: James Morris <james.morris@microsoft.com> Reviewed-by: John Johansen <john.johansen@canonical.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-10ima: open a new file instance if no read permissionsGoldwyn Rodrigues
Open a new file instance as opposed to changing file->f_mode when the file is not readable. This is done to accomodate overlayfs stacked file operations change. The real struct file is hidden behind the overlays struct file. So, any file->f_mode manipulations are not reflected on the real struct file. Open the file again in read mode if original file cannot be read, read and calculate the hash. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Cc: stable@vger.kernel.org (linux-4.19) Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-10-10ima: fix showing large 'violations' or 'runtime_measurements_count'Eric Biggers
The 12 character temporary buffer is not necessarily long enough to hold a 'long' value. Increase it. Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-10-10security/integrity: remove unnecessary 'init_keyring' variableEric Biggers
The 'init_keyring' variable actually just gave the value of CONFIG_INTEGRITY_TRUSTED_KEYRING. We should check the config option directly instead. No change in behavior; this just simplifies the code. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-10-10security/integrity: constify some read-only dataEric Biggers
Constify some static data that is never modified, so that it is placed in .rodata. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-08-15Merge branch 'next-integrity' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull integrity updates from James Morris: "This adds support for EVM signatures based on larger digests, contains a new audit record AUDIT_INTEGRITY_POLICY_RULE to differentiate the IMA policy rules from the IMA-audit messages, addresses two deadlocks due to either loading or searching for crypto algorithms, and cleans up the audit messages" * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: EVM: fix return value check in evm_write_xattrs() integrity: prevent deadlock during digsig verification. evm: Allow non-SHA1 digital signatures evm: Don't deadlock if a crypto algorithm is unavailable integrity: silence warning when CONFIG_SECURITYFS is not enabled ima: Differentiate auditing policy rules from "audit" actions ima: Do not audit if CONFIG_INTEGRITY_AUDIT is not set ima: Use audit_log_format() rather than audit_log_string() ima: Call audit_log_string() rather than logging it untrusted
2018-08-15Merge branch 'next-tpm' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull TPM updates from James Morris: - Migrate away from PM runtime as explicit cmdReady/goIdle transactions for every command is a spec requirement. PM runtime adds only a layer of complexity on our case. - tpm_tis drivers can now specify the hwrng quality. - TPM 2.0 code uses now tpm_buf for constructing messages. Jarkko thinks Tomas Winkler has done the same for TPM 1.2, and will start digging those changes from the patchwork in the near future. - Bug fixes and clean ups * 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: ima: Get rid of ima_used_chip and use ima_tpm_chip != NULL instead ima: Use tpm_default_chip() and call TPM functions with a tpm_chip tpm: replace TPM_TRANSMIT_RAW with TPM_TRANSMIT_NESTED tpm: Convert tpm_find_get_ops() to use tpm_default_chip() tpm: Implement tpm_default_chip() to find a TPM chip tpm: rename tpm_chip_find_get() to tpm_find_get_ops() tpm: Allow tpm_tis drivers to set hwrng quality. tpm: Return the actual size when receiving an unsupported command tpm: separate cmd_ready/go_idle from runtime_pm tpm/tpm_i2c_infineon: switch to i2c_lock_bus(..., I2C_LOCK_SEGMENT) tpm_tis_spi: Pass the SPI IRQ down to the driver tpm: migrate tpm2_get_random() to use struct tpm_buf tpm: migrate tpm2_get_tpm_pt() to use struct tpm_buf tpm: migrate tpm2_probe() to use struct tpm_buf tpm: migrate tpm2_shutdown() to use struct tpm_buf
2018-08-15Merge branch 'next-general' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: - kstrdup() return value fix from Eric Biggers - Add new security_load_data hook to differentiate security checking of kernel-loaded binaries in the case of there being no associated file descriptor, from Mimi Zohar. - Add ability to IMA to specify a policy at build-time, rather than just via command line params or by loading a custom policy, from Mimi. - Allow IMA and LSMs to prevent sysfs firmware load fallback (e.g. if using signed firmware), from Mimi. - Allow IMA to deny loading of kexec kernel images, as they cannot be measured by IMA, from Mimi. * 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: security: check for kstrdup() failure in lsm_append() security: export security_kernel_load_data function ima: based on policy warn about loading firmware (pre-allocated buffer) module: replace the existing LSM hook in init_module ima: add build time policy ima: based on policy require signed firmware (sysfs fallback) firmware: add call to LSM hook before firmware sysfs fallback ima: based on policy require signed kexec kernel images kexec: add call to LSM hook in original kexec_load syscall security: define new LSM hook named security_kernel_load_data MAINTAINERS: remove the outdated "LINUX SECURITY MODULE (LSM) FRAMEWORK" entry
2018-07-28ima: Get rid of ima_used_chip and use ima_tpm_chip != NULL insteadStefan Berger
Get rid of ima_used_chip and use ima_tpm_chip variable instead for determining whether to use the TPM chip. Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-07-28ima: Use tpm_default_chip() and call TPM functions with a tpm_chipStefan Berger
Rather than accessing the TPM functions by passing a NULL pointer for the tpm_chip, which causes a lookup for a suitable chip every time, get a hold of a tpm_chip and access the TPM functions using it. Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
2018-07-22EVM: fix return value check in evm_write_xattrs()Wei Yongjun
In case of error, the function audit_log_start() returns NULL pointer not ERR_PTR(). The IS_ERR() test in the return value check should be replaced with NULL test. Fixes: fa516b66a1bf ("EVM: Allow runtime modification of the set of verified xattrs") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2018-07-18integrity: prevent deadlock during digsig verification.Mikhail Kurinnoi
This patch aimed to prevent deadlock during digsig verification.The point of issue - user space utility modprobe and/or it's dependencies (ld-*.so, libz.so.*, libc-*.so and /lib/modules/ files) that could be used for kernel modules load during digsig verification and could be signed by digsig in the same time. First at all, look at crypto_alloc_tfm() work algorithm: crypto_alloc_tfm() will first attempt to locate an already loaded algorithm. If that fails and the kernel supports dynamically loadable modules, it will then attempt to load a module of the same name or alias. If that fails it will send a query to any loaded crypto manager to construct an algorithm on the fly. We have situation, when public_key_verify_signature() in case of RSA algorithm use alg_name to store internal information in order to construct an algorithm on the fly, but crypto_larval_lookup() will try to use alg_name in order to load kernel module with same name. 1) we can't do anything with crypto module work, since it designed to work exactly in this way; 2) we can't globally filter module requests for modprobe, since it designed to work with any requests. In this patch, I propose add an exception for "crypto-pkcs1pad(rsa,*)" module requests only in case of enabled integrity asymmetric keys support. Since we don't have any real "crypto-pkcs1pad(rsa,*)" kernel modules for sure, we are safe to fail such module request from crypto_larval_lookup(). In this way we prevent modprobe execution during digsig verification and avoid possible deadlock if modprobe and/or it's dependencies also signed with digsig. Requested "crypto-pkcs1pad(rsa,*)" kernel module name formed by: 1) "pkcs1pad(rsa,%s)" in public_key_verify_signature(); 2) "crypto-%s" / "crypto-%s-all" in crypto_larval_lookup(). "crypto-pkcs1pad(rsa," part of request is a constant and unique and could be used as filter. Signed-off-by: Mikhail Kurinnoi <viewizard@viewizard.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> include/linux/integrity.h | 13 +++++++++++++ security/integrity/digsig_asymmetric.c | 23 +++++++++++++++++++++++ security/security.c | 7 ++++++- 3 files changed, 42 insertions(+), 1 deletion(-)
2018-07-18evm: Allow non-SHA1 digital signaturesMatthew Garrett
SHA1 is reasonable in HMAC constructs, but it's desirable to be able to use stronger hashes in digital signatures. Modify the EVM crypto code so the hash type is imported from the digital signature and passed down to the hash calculation code, and return the digest size to higher layers for validation. Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-07-18evm: Don't deadlock if a crypto algorithm is unavailableMatthew Garrett
When EVM attempts to appraise a file signed with a crypto algorithm the kernel doesn't have support for, it will cause the kernel to trigger a module load. If the EVM policy includes appraisal of kernel modules this will in turn call back into EVM - since EVM is holding a lock until the crypto initialisation is complete, this triggers a deadlock. Add a CRYPTO_NOLOAD flag and skip module loading if it's set, and add that flag in the EVM case in order to fail gracefully with an error message instead of deadlocking. Signed-off-by: Matthew Garrett <mjg59@google.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-07-18integrity: silence warning when CONFIG_SECURITYFS is not enabledSudeep Holla
When CONFIG_SECURITYFS is not enabled, securityfs_create_dir returns -ENODEV which throws the following error: "Unable to create integrity sysfs dir: -19" However, if the feature is disabled, it can't be warning and hence we need to silence the error. This patch checks for the error -ENODEV which is returned when CONFIG_SECURITYFS is disabled to stop the error being thrown. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2018-07-18ima: Differentiate auditing policy rules from "audit" actionsStefan Berger
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>
2018-07-18ima: Do not audit if CONFIG_INTEGRITY_AUDIT is not setStefan Berger
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>
2018-07-18ima: Use audit_log_format() rather than audit_log_string()Stefan Berger
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>
2018-07-18ima: Call audit_log_string() rather than logging it untrustedStefan Berger
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>
2018-07-16ima: based on policy warn about loading firmware (pre-allocated buffer)Mimi Zohar
Some systems are memory constrained but they need to load very large firmwares. The firmware subsystem allows drivers to request this firmware be loaded from the filesystem, but this requires that the entire firmware be loaded into kernel memory first before it's provided to the driver. This can lead to a situation where we map the firmware twice, once to load the firmware into kernel memory and once to copy the firmware into the final resting place. To resolve this problem, commit a098ecd2fa7d ("firmware: support loading into a pre-allocated buffer") introduced request_firmware_into_buf() API that allows drivers to request firmware be loaded directly into a pre-allocated buffer. Do devices using pre-allocated memory run the risk of the firmware being accessible to the device prior to the completion of IMA's signature verification any more than when using two buffers? (Refer to mailing list discussion[1]). Only on systems with an IOMMU can the access be prevented. As long as the signature verification completes prior to the DMA map is performed, the device can not access the buffer. This implies that the same buffer can not be re-used. Can we ensure the buffer has not been DMA mapped before using the pre-allocated buffer? [1] https://lkml.org/lkml/2018/7/10/56 Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Stephen Boyd <sboyd@kernel.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-07-16module: replace the existing LSM hook in init_moduleMimi Zohar
Both the init_module and finit_module syscalls call either directly or indirectly the security_kernel_read_file LSM hook. This patch replaces the direct call in init_module with a call to the new security_kernel_load_data hook and makes the corresponding changes in SELinux, LoadPin, and IMA. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Jeff Vander Stoep <jeffv@google.com> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: Kees Cook <keescook@chromium.org> Acked-by: Jessica Yu <jeyu@kernel.org> Acked-by: Paul Moore <paul@paul-moore.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-07-16ima: add build time policyMimi Zohar
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>