For a while it was looked down upon to directly read files from Linux. These days there exists a few mechanisms in the kernel that do just this though to load a file into a local buffer. There are minor but important checks differences on each, we should take all the best practices from each of them, generalize them and make all places in the kernel that read a file use it.[1] One difference is the method for opening the file. In some cases we have a file, while in other cases we have a pathname or a file descriptor. Another difference is the security hook calls, or lack of them. In some versions there is a post file read hook, while in others there is a pre file read hook. This patch set attempts to resolve these differences. It does not attempt to merge the different methods of opening a file, but defines a single common kernel file read function with two wrappers. In addition, as none of the upstreamed LSMs define either a kernel_module_from_file or a kernel_fw_from_file hook, this patch set removes these hooks and the associated functions. The ima_module_check() and ima_fw_from_file() functions are renamed and called from the pre and post kernel_read_file security functions respectively. Changelog: - First four IMA patches removed from this patch set. - Cleaned up the kernel_read_file_id to ima_hooks enumeration mapping. - Renamed the kexec IMA policy identifiers. - Added missing include file for other architectures. - Rebased on top of some of the "firmware_class: extensible firmware API" patches posted by Luis. - Removed the kernel_module_from_file and kernel_fw_from_file security hooks and functions. - Defined "kernel_read_file_id" enumeration, independently of "ima_hooks". - Split patches for ease of review. The latest version of these patches can be found in the next-kernel-read branch of: git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git [1] Taken from Luis Rodriguez's wiki - http://kernelnewbies.org/KernelProjects/common-kernel-loader Mimi Dmitry Kasatkin (2): ima: provide buffer hash calculation function ima: load policy using path Kees Cook (1): firmware: clean up filesystem load exit path Luis R. Rodriguez (2): firmware: simplify dev_*() print messages for generic helpers firmware: move completing fw into a helper Mimi Zohar (14): vfs: define a generic function to read a file from the kernel vfs: define kernel_read_file_id enumeration ima: calculate the hash of a buffer using aynchronous hash(ahash) ima: define a new hook to measure and appraise a file already in memory vfs: define kernel_read_file_from_path firmware: replace call to fw_read_file_contents() with kernel version security: define kernel_read_file hook vfs: define kernel_copy_file_from_fd() module: replace copy_module_from_fd with kernel version ima: remove firmware and module specific cached status info kexec: replace call to copy_file_from_fd() with kernel version ima: support for kexec image and initramfs ima: measure and appraise the IMA policy itself ima: require signed IMA policy Documentation/ABI/testing/ima_policy | 1 + drivers/base/firmware_class.c | 74 +++++++-------------- fs/exec.c | 95 +++++++++++++++++++++++++++ include/linux/fs.h | 15 +++++ include/linux/ima.h | 10 +-- include/linux/lsm_hooks.h | 35 +++++----- include/linux/security.h | 16 +++-- kernel/kexec_file.c | 73 +++------------------ kernel/module.c | 68 +++----------------- security/integrity/iint.c | 4 +- security/integrity/ima/ima.h | 13 +++- security/integrity/ima/ima_api.c | 6 +- security/integrity/ima/ima_appraise.c | 37 +++++------ security/integrity/ima/ima_crypto.c | 118 ++++++++++++++++++++++++++++++++++ security/integrity/ima/ima_fs.c | 51 ++++++++++++++- security/integrity/ima/ima_main.c | 73 ++++++++++++++++----- security/integrity/ima/ima_policy.c | 41 ++++++++++-- security/integrity/integrity.h | 15 ++--- security/security.c | 32 ++++----- 19 files changed, 499 insertions(+), 278 deletions(-) -- 2.1.0
