linux-dev/security/selinux/Makefile, branch master

selinux: include a consumer of the new IMA critical data hook

2021-01-15T04:41:46Z

SELinux stores the active policy in memory, so the changes to this data at runtime would have an impact on the security guarantees provided by SELinux. Measuring in-memory SELinux policy through IMA subsystem provides a secure way for the attestation service to remotely validate the policy contents at runtime. Measure the hash of the loaded policy by calling the IMA hook ima_measure_critical_data(). Since the size of the loaded policy can be large (several MB), measure the hash of the policy instead of the entire policy to avoid bloating the IMA log entry. To enable SELinux data measurement, the following steps are required: 1, Add "ima_policy=critical_data" to the kernel command line arguments to enable measuring SELinux data at boot time. For example, BOOT_IMAGE=/boot/vmlinuz-5.10.0-rc1+ root=UUID=fd643309-a5d2-4ed3-b10d-3c579a5fab2f ro nomodeset security=selinux ima_policy=critical_data 2, Add the following rule to /etc/ima/ima-policy measure func=CRITICAL_DATA label=selinux Sample measurement of the hash of SELinux policy: To verify the measured data with the current SELinux policy run the following commands and verify the output hash values match. sha256sum /sys/fs/selinux/policy | cut -d' ' -f 1 grep "selinux-policy-hash" /sys/kernel/security/integrity/ima/ascii_runtime_measurements | tail -1 | cut -d' ' -f 6 Note that the actual verification of SELinux policy would require loading the expected policy into an identical kernel on a pristine/known-safe system and run the sha256sum /sys/kernel/selinux/policy there to get the expected hash. Signed-off-by: Lakshmi Ramasubramanian Suggested-by: Stephen Smalley Acked-by: Paul Moore Reviewed-by: Tyler Hicks Signed-off-by: Mimi Zohar

selinux: hash context structure directly

2020-04-17T20:04:34Z

Always hashing the string representation is inefficient. Just hash the contents of the structure directly (using jhash). If the context is invalid (str & len are set), then hash the string as before, otherwise hash the structured data. Since the context hashing function is now faster (about 10 times), this patch decreases the overhead of security_transition_sid(), which is called from many hooks. The jhash function seemed as a good choice, since it is used as the default hashing algorithm in rhashtable. Signed-off-by: Ondrej Mosnacek Reviewed-by: Jeff Vander Stoep Tested-by: Jeff Vander Stoep [PM: fixed some spelling errors in the comments pointed out by JVS] Signed-off-by: Paul Moore

selinux: move status variables out of selinux_ss

2020-02-10T15:49:01Z

It fits more naturally in selinux_state, since it reflects also global state (the enforcing and policyload fields). Signed-off-by: Ondrej Mosnacek Reviewed-by: Stephen Smalley Signed-off-by: Paul Moore

selinux: move ibpkeys code under CONFIG_SECURITY_INFINIBAND.

2020-01-10T16:56:37Z

Move cache based pkey sid retrieval code which was added with commit "409dcf31" under CONFIG_SECURITY_INFINIBAND. As its going to alloc a new cache which impacts low RAM devices which was enabled by default. Suggested-by: Paul Moore Signed-off-by: Ravi Kumar Siddojigari [PM: checkpatch.pl cleanups, fixed capitalization in the description] Signed-off-by: Paul Moore

SELinux: Remove unused selinux_is_enabled

2019-01-08T21:18:44Z

There are no longer users of selinux_is_enabled(). Remove it. As selinux_is_enabled() is the only reason for include/linux/selinux.h remove that as well. Signed-off-by: Casey Schaufler Reviewed-by: Kees Cook Signed-off-by: Kees Cook

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

selinux: Add a cache for quicker retreival of PKey SIDs

2017-05-23T16:28:12Z

It is likely that the SID for the same PKey will be requested many times. To reduce the time to modify QPs and process MADs use a cache to store PKey SIDs. This code is heavily based on the "netif" and "netport" concept originally developed by James Morris and Paul Moore (see security/selinux/netif.c and security/selinux/netport.c for more information) Signed-off-by: Daniel Jurgens Acked-by: Doug Ledford Signed-off-by: Paul Moore

selinux: use absolute path to include directory

2016-01-28T15:37:15Z

Compiler warns us a lot that it can't find include folder because it's provided in relative form. CC security/selinux/netlabel.o cc1: warning: security/selinux/include: No such file or directory cc1: warning: security/selinux/include: No such file or directory cc1: warning: security/selinux/include: No such file or directory cc1: warning: security/selinux/include: No such file or directory Add $(srctree) prefix to the path. Signed-off-by: Andy Shevchenko [PM: minor description edits to fit under 80char width] Signed-off-by: Paul Moore

selinux: change to new flag variable

2010-10-20T23:12:40Z

Replace EXTRA_CFLAGS with ccflags-y. Signed-off-by: matt mooney Signed-off-by: James Morris

selinux: really fix dependency causing parallel compile failure.

2010-10-20T23:12:39Z

While the previous change to the selinux Makefile reduced the window significantly for this failure, it is still possible to see a compile failure where cpp starts processing selinux files before the auto generated flask.h file is completed. This is easily reproduced by adding the following temporary change to expose the issue everytime: - cmd_flask = scripts/selinux/genheaders/genheaders ... + cmd_flask = sleep 30 ; scripts/selinux/genheaders/genheaders ... This failure happens because the creation of the object files in the ss subdir also depends on flask.h. So simply incorporate them into the parent Makefile, as the ss/Makefile really doesn't do anything unique. With this change, compiling of all selinux files is dependent on completion of the header file generation, and this test case with the "sleep 30" now confirms it is functioning as expected. Signed-off-by: Paul Gortmaker Signed-off-by: James Morris