kernel/linux.git/security/integrity/ima/ima_template.c, branch v5.18

ima: Allow template selection with ima_template[_fmt]= after ima_hash=

2022-02-02T16:59:54+00:00

Commit c2426d2ad5027 ("ima: added support for new kernel cmdline parameter ima_template_fmt") introduced an additional check on the ima_template variable to avoid multiple template selection. Unfortunately, ima_template could be also set by the setup function of the ima_hash= parameter, when it calls ima_template_desc_current(). This causes attempts to choose a new template with ima_template= or with ima_template_fmt=, after ima_hash=, to be ignored. Achieve the goal of the commit mentioned with the new static variable template_setup_done, so that template selection requests after ima_hash= are not ignored. Finally, call ima_init_template_list(), if not already done, to initialize the list of templates before lookup_template_desc() is called. Reported-by: Guo Zihua Signed-off-by: Roberto Sassu Cc: stable@vger.kernel.org Fixes: c2426d2ad5027 ("ima: added support for new kernel cmdline parameter ima_template_fmt") Signed-off-by: Mimi Zohar

ima: Set correct casting types

2021-06-08T20:29:10+00:00

The code expects that the values being parsed from a buffer when the ima_canonical_fmt global variable is true are in little endian. Thus, this patch sets the casting types accordingly. Reported-by: kernel test robot Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar

ima: Define new template evm-sig

2021-06-03T14:02:37+00:00

With the recent introduction of the evmsig template field, remote verifiers can obtain the EVM portable signature instead of the IMA signature, to verify file metadata. After introducing the new fields to include file metadata in the measurement list, this patch finally defines the evm-sig template, whose format is: d-ng|n-ng|evmsig|xattrnames|xattrlengths|xattrvalues|iuid|igid|imode xattrnames, xattrlengths and xattrvalues are populated only from defined EVM protected xattrs, i.e. the ones that EVM considers to verify the portable signature. xattrnames and xattrlengths are populated only if the xattr is present. xattrnames and xattrlengths are not necessary for verifying the EVM portable signature, but they are included for completeness of information, if a remote verifier wants to infer more from file metadata. Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar

ima: Define new template fields xattrnames, xattrlengths and xattrvalues

2021-06-02T22:56:13+00:00

This patch defines the new template fields xattrnames, xattrlengths and xattrvalues, which contain respectively a list of xattr names (strings, separated by |), lengths (u32, hex) and values (hex). If an xattr is not present, the name and length are not displayed in the measurement list. Reported-by: kernel test robot (Missing prototype def) Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar

ima: Define new template field imode

2021-06-01T19:17:30+00:00

This patch defines the new template field imode, which includes the inode mode. It can be used by a remote verifier to verify the EVM portable signature, if it was included with the template fields sig or evmsig. Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar

ima: Define new template fields iuid and igid

2021-06-01T19:17:30+00:00

This patch defines the new template fields iuid and igid, which include respectively the inode UID and GID. For idmapped mounts, still the original UID and GID are provided. These fields can be used to verify the EVM portable signature, if it was included with the template fields sig or evmsig. Signed-off-by: Roberto Sassu Acked-by: Christian Brauner Signed-off-by: Mimi Zohar

ima: Introduce template field evmsig and write to field sig as fallback

2021-06-01T16:30:51+00:00

With the patch to accept EVM portable signatures when the appraise_type=imasig requirement is specified in the policy, appraisal can be successfully done even if the file does not have an IMA signature. However, remote attestation would not see that a different signature type was used, as only IMA signatures can be included in the measurement list. This patch solves the issue by introducing the new template field 'evmsig' to show EVM portable signatures and by including its value in the existing field 'sig' if the IMA signature is not found. Suggested-by: Mimi Zohar Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar

ima: Fix the error code for restoring the PCR value

2021-03-24T11:14:53+00:00

In ima_restore_measurement_list(), hdr[HDR_PCR].data is pointing to a buffer of type u8, which contains the dumped 32-bit pcr value. Currently, only the least significant byte is used to restore the pcr value. We should convert hdr[HDR_PCR].data to a pointer of type u32 before fetching the value to restore the correct pcr value. Fixes: 47fdee60b47f ("ima: use ima_parse_buf() to parse measurements headers") Signed-off-by: Li Huafei Reviewed-by: Roberto Sassu Signed-off-by: Mimi Zohar

ima: select ima-buf template for buffer measurement

2020-11-20T18:52:43+00:00

The default IMA template used for all policy rules is the value set for CONFIG_IMA_DEFAULT_TEMPLATE if the policy rule does not specify a template. The default IMA template for buffer measurements should be 'ima-buf' - so that the measured buffer is correctly included in the IMA measurement log entry. With the default template format, buffer measurements are added to the measurement list, but do not include the buffer data, making it difficult, if not impossible, to validate. Including 'ima-buf' template records in the measurement list by default, should not impact existing attestation servers without 'ima-buf' template support. Initialize a global 'ima-buf' template and select that template, by default, for buffer measurements. Signed-off-by: Lakshmi Ramasubramanian Signed-off-by: Mimi Zohar

Merge tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

2020-08-11T21:30:36+00:00

Pull security subsystem updates from James Morris: "A couple of minor documentation updates only for this release" * tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: LSM: drop duplicated words in header file comments Replace HTTP links with HTTPS ones: security