#
75a323e6 |
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15-Feb-2024 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Make it independent from 'integrity' LSM Define a new structure for EVM-specific metadata, called evm_iint_cache, and embed it in the inode security blob. Introduce evm_iint_inode() to retrieve metadata, and register evm_inode_alloc_security() for the inode_alloc_security LSM hook, to initialize the structure (before splitting metadata, this task was done by iint_init_always()). Keep the non-NULL checks after calling evm_iint_inode() except in evm_inode_alloc_security(), to take into account inodes for which security_inode_alloc() was not called. When using shared metadata, obtaining a NULL pointer from integrity_iint_find() meant that the file wasn't in the IMA policy. Now, because IMA and EVM use disjoint metadata, the EVM status has to be stored for every inode regardless of the IMA policy. Given that from now on EVM relies on its own metadata, remove the iint parameter from evm_verifyxattr(). Also, directly retrieve the iint in evm_verify_hmac(), called by both evm_verifyxattr() and evm_verify_current_integrity(), since now there is no performance penalty in retrieving EVM metadata (constant time). Replicate the management of the IMA_NEW_FILE flag, by introducing evm_post_path_mknod() and evm_file_release() to respectively set and clear the newly introduced flag EVM_NEW_FILE, at the same time IMA does. Like for IMA, select CONFIG_SECURITY_PATH when EVM is enabled, to ensure that files are marked as new. Unlike ima_post_path_mknod(), evm_post_path_mknod() cannot check if a file must be appraised. Thus, it marks all affected files. Also, it does not clear EVM_NEW_FILE depending on i_version, but that is not a problem because IMA_NEW_FILE is always cleared when set in ima_check_last_writer(). Move the EVM-specific flag EVM_IMMUTABLE_DIGSIG to security/integrity/evm/evm.h, since that definition is now unnecessary in the common integrity layer. Finally, switch to the LSM reservation mechanism for the EVM xattr, and consequently decrement by one the number of xattrs to allocate in security_inode_init_security(). Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
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#
c31288e5 |
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10-Jun-2023 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Support multiple LSMs providing an xattr Currently, evm_inode_init_security() processes a single LSM xattr from the array passed by security_inode_init_security(), and calculates the HMAC on it and other inode metadata. As the LSM infrastructure now can pass to EVM an array with multiple xattrs, scan them until the terminator (xattr name NULL), and calculate the HMAC on all of them. Also, double check that the xattrs array terminator is the first non-filled slot (obtained with lsm_get_xattr_slot()). Consumers of the xattrs array, such as the initxattrs() callbacks, rely on the terminator. Finally, change the name of the lsm_xattr parameter of evm_init_hmac() to xattrs, to reflect the new type of information passed. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
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#
996e0a97 |
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06-Jun-2023 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Fix build warnings Fix build warnings (function parameters description) for evm_read_protected_xattrs(), evm_set_key() and evm_verifyxattr(). Fixes: 7626676320f3 ("evm: provide a function to set the EVM key from the kernel") # v4.5+ Fixes: 8314b6732ae4 ("ima: Define new template fields xattrnames, xattrlengths and xattrvalues") # v5.14+ Fixes: 2960e6cb5f7c ("evm: additional parameter to pass integrity cache entry 'iint'") # v3.2+ Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
8250865c |
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30-Jan-2023 |
Xiu Jianfeng <xiujianfeng@huawei.com> |
evm: call dump_security_xattr() in all cases to remove code duplication Currently dump_security_xattr() is used to dump security xattr value which is larger than 64 bytes, otherwise, pr_debug() is used. In order to remove code duplication, refactor dump_security_xattr() and call it in all cases. Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
39f60c1c |
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12-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port xattr to mnt_idmap Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
4609e1f1 |
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12-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port ->permission() to pass mnt_idmap Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
f6fbd8cb |
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09-Nov-2022 |
Paul Moore <paul@paul-moore.com> |
lsm,fs: fix vfs_getxattr_alloc() return type and caller error paths The vfs_getxattr_alloc() function currently returns a ssize_t value despite the fact that it only uses int values internally for return values. Fix this by converting vfs_getxattr_alloc() to return an int type and adjust the callers as necessary. As part of these caller modifications, some of the callers are fixed to properly free the xattr value buffer on both success and failure to ensure that memory is not leaked in the failure case. Reviewed-by: Serge Hallyn <serge@hallyn.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
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#
51dd64bb |
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27-May-2022 |
Xiu Jianfeng <xiujianfeng@huawei.com> |
Revert "evm: Fix memleak in init_desc" This reverts commit ccf11dbaa07b328fa469415c362d33459c140a37. Commit ccf11dbaa07b ("evm: Fix memleak in init_desc") said there is memleak in init_desc. That may be incorrect, as we can see, tmp_tfm is saved in one of the two global variables hmac_tfm or evm_tfm[hash_algo], then if init_desc is called next time, there is no need to alloc tfm again, so in the error path of kmalloc desc or crypto_shash_init(desc), It is not a problem without freeing tmp_tfm. And also that commit did not reset the global variable to NULL after freeing tmp_tfm and this makes *tfm a dangling pointer which may cause a UAF issue. Reported-by: Guozihua (Scott) <guozihua@huawei.com> Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
4c41186f |
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13-May-2022 |
Stefan Berger <stefanb@linux.ibm.com> |
evm: Clean up some variables Make hmac_tfm static since it's not used anywhere else besides the file it is in. Remove declaration of hash_tfm since it doesn't exist. Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
907a399d |
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21-Jun-2021 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Check xattr size discrepancy between kernel and user The kernel and the user obtain an xattr value in two different ways: kernel (EVM): uses vfs_getxattr_alloc() which obtains the xattr value from the filesystem handler (raw value); user (ima-evm-utils): uses vfs_getxattr() which obtains the xattr value from the LSMs (normalized value). Normally, this does not have an impact unless security.selinux is set with setfattr, with a value not terminated by '\0' (this is not the recommended way, security.selinux should be set with the appropriate tools such as chcon and restorecon). In this case, the kernel and the user see two different xattr values: the former sees the xattr value without '\0' (raw value), the latter sees the value with '\0' (value normalized by SELinux). This could result in two different verification outcomes from EVM and ima-evm-utils, if a signature was calculated with a security.selinux value terminated by '\0' and the value set in the filesystem is not terminated by '\0'. The former would report verification failure due to the missing '\0', while the latter would report verification success (because it gets the normalized value with '\0'). This patch mitigates this issue by comparing in evm_calc_hmac_or_hash() the size of the xattr returned by the two xattr functions and by warning the user if there is a discrepancy. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Suggested-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
87ac3d00 |
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13-May-2021 |
Mimi Zohar <zohar@linux.ibm.com> |
evm: output EVM digest calculation info Output the data used in calculating the EVM digest and the resulting digest as ascii hexadecimal strings. Suggested-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> (CONFIG_DYNAMIC_DEBUG) Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Reported-by: kernel test robot <lkp@intel.com> (Use %zu for size_t) Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
8c7a703e |
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28-May-2021 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Verify portable signatures against all protected xattrs Currently, the evm_config_default_xattrnames array contains xattr names only related to LSMs which are enabled in the kernel configuration. However, EVM portable signatures do not depend on local information and a vendor might include in the signature calculation xattrs that are not enabled in the target platform. Just including all xattrs names in evm_config_default_xattrnames is not a safe approach, because a target system might have already calculated signatures or HMACs based only on the enabled xattrs. After applying this patch, EVM would verify those signatures and HMACs with all xattrs instead. The non-enabled ones, which could possibly exist, would cause a verification error. Thus, this patch adds a new field named enabled to the xattr_list structure, which is set to true if the LSM associated to a given xattr name is enabled in the kernel configuration. The non-enabled xattrs are taken into account only in evm_calc_hmac_or_hash(), if the passed security.evm type is EVM_XATTR_PORTABLE_DIGSIG. The new function evm_protected_xattr_if_enabled() has been defined so that IMA can include all protected xattrs and not only the enabled ones in the measurement list, if the new template fields xattrnames, xattrlengths or xattrvalues have been included in the template format. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
c7c7a1a1 |
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21-Jan-2021 |
Tycho Andersen <tycho@tycho.pizza> |
xattr: handle idmapped mounts When interacting with extended attributes the vfs verifies that the caller is privileged over the inode with which the extended attribute is associated. For posix access and posix default extended attributes a uid or gid can be stored on-disk. Let the functions handle posix extended attributes on idmapped mounts. If the inode is accessed through an idmapped mount we need to map it according to the mount's user namespace. Afterwards the checks are identical to non-idmapped mounts. This has no effect for e.g. security xattrs since they don't store uids or gids and don't perform permission checks on them like posix acls do. Link: https://lore.kernel.org/r/20210121131959.646623-10-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Tycho Andersen <tycho@tycho.pizza> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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#
ccf11dba |
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10-Jan-2021 |
Dinghao Liu <dinghao.liu@zju.edu.cn> |
evm: Fix memleak in init_desc tmp_tfm is allocated, but not freed on subsequent kmalloc failure, which leads to a memory leak. Free tmp_tfm. Fixes: d46eb3699502b ("evm: crypto hash replaced by shash") Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn> [zohar@linux.ibm.com: formatted/reworded patch description] Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
84338569 |
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12-May-2020 |
Dan Carpenter <dan.carpenter@oracle.com> |
evm: Fix a small race in init_desc() The IS_ERR_OR_NULL() function has two conditions and if we got really unlucky we could hit a race where "ptr" started as an error pointer and then was set to NULL. Both conditions would be false even though the pointer at the end was NULL. This patch fixes the problem by ensuring that "*tfm" can only be NULL or valid. I have introduced a "tmp_tfm" variable to make that work. I also reversed a condition and pulled the code in one tab. Reported-by: Roberto Sassu <roberto.sassu@huawei.com> Fixes: 53de3b080d5e ("evm: Check also if *tfm is an error pointer in init_desc()") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Roberto Sassu <roberto.sassu@huawei.com> Acked-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
0c4395fb |
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14-Apr-2020 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Fix possible memory leak in evm_calc_hmac_or_hash() Don't immediately return if the signature is portable and security.ima is not present. Just set error so that memory allocated is freed before returning from evm_calc_hmac_or_hash(). Fixes: 50b977481fce9 ("EVM: Add support for portable signature format") Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
770f6058 |
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30-Apr-2020 |
Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com> |
evm: Fix RCU list related warnings This patch fixes the following warning and few other instances of traversal of evm_config_xattrnames list: [ 32.848432] ============================= [ 32.848707] WARNING: suspicious RCU usage [ 32.848966] 5.7.0-rc1-00006-ga8d5875ce5f0b #1 Not tainted [ 32.849308] ----------------------------- [ 32.849567] security/integrity/evm/evm_main.c:231 RCU-list traversed in non-reader section!! Since entries are only added to the list and never deleted, use list_for_each_entry_lockless() instead of list_for_each_entry_rcu for traversing the list. Also, add a relevant comment in evm_secfs.c to indicate this fact. Reported-by: kernel test robot <lkp@intel.com> Suggested-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> (RCU viewpoint) Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
53de3b08 |
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26-Apr-2020 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Check also if *tfm is an error pointer in init_desc() This patch avoids a kernel panic due to accessing an error pointer set by crypto_alloc_shash(). It occurs especially when there are many files that require an unsupported algorithm, as it would increase the likelihood of the following race condition: Task A: *tfm = crypto_alloc_shash() <= error pointer Task B: if (*tfm == NULL) <= *tfm is not NULL, use it Task B: rc = crypto_shash_init(desc) <= panic Task A: *tfm = NULL This patch uses the IS_ERR_OR_NULL macro to determine whether or not a new crypto context must be created. Cc: stable@vger.kernel.org Fixes: d46eb3699502b ("evm: crypto hash replaced by shash") Co-developed-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com> Signed-off-by: Krzysztof Struczynski <krzysztof.struczynski@huawei.com> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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555d6d71 |
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18-Feb-2020 |
Tushar Sugandhi <tusharsu@linux.microsoft.com> |
integrity: Remove duplicate pr_fmt definitions The #define for formatting log messages, pr_fmt, is duplicated in the files under security/integrity. This change moves the definition to security/integrity/integrity.h and removes the duplicate definitions in the other files under security/integrity. With this change, the messages in the following files will be prefixed with 'integrity'. security/integrity/platform_certs/platform_keyring.c security/integrity/platform_certs/load_powerpc.c security/integrity/platform_certs/load_uefi.c security/integrity/iint.c e.g. "integrity: Error adding keys to platform keyring %s\n" And the messages in the following file will be prefixed with 'ima'. security/integrity/ima/ima_mok.c e.g. "ima: Allocating IMA blacklist keyring.\n" For the rest of the files under security/integrity, there will be no change in the message format. Suggested-by: Shuah Khan <skhan@linuxfoundation.org> Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
028db3e2 |
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10-Jul-2019 |
Linus Torvalds <torvalds@linux-foundation.org> |
Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs" This reverts merge 0f75ef6a9cff49ff612f7ce0578bced9d0b38325 (and thus effectively commits 7a1ade847596 ("keys: Provide KEYCTL_GRANT_PERMISSION") 2e12256b9a76 ("keys: Replace uid/gid/perm permissions checking with an ACL") that the merge brought in). It turns out that it breaks booting with an encrypted volume, and Eric biggers reports that it also breaks the fscrypt tests [1] and loading of in-kernel X.509 certificates [2]. The root cause of all the breakage is likely the same, but David Howells is off email so rather than try to work it out it's getting reverted in order to not impact the rest of the merge window. [1] https://lore.kernel.org/lkml/20190710011559.GA7973@sol.localdomain/ [2] https://lore.kernel.org/lkml/20190710013225.GB7973@sol.localdomain/ Link: https://lore.kernel.org/lkml/CAHk-=wjxoeMJfeBahnWH=9zShKp2bsVy527vo3_y8HfOdhwAAw@mail.gmail.com/ Reported-by: Eric Biggers <ebiggers@kernel.org> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
2e12256b |
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27-Jun-2019 |
David Howells <dhowells@redhat.com> |
keys: Replace uid/gid/perm permissions checking with an ACL Replace the uid/gid/perm permissions checking on a key with an ACL to allow the SETATTR and SEARCH permissions to be split. This will also allow a greater range of subjects to represented. ============ WHY DO THIS? ============ The problem is that SETATTR and SEARCH cover a slew of actions, not all of which should be grouped together. For SETATTR, this includes actions that are about controlling access to a key: (1) Changing a key's ownership. (2) Changing a key's security information. (3) Setting a keyring's restriction. And actions that are about managing a key's lifetime: (4) Setting an expiry time. (5) Revoking a key. and (proposed) managing a key as part of a cache: (6) Invalidating a key. Managing a key's lifetime doesn't really have anything to do with controlling access to that key. Expiry time is awkward since it's more about the lifetime of the content and so, in some ways goes better with WRITE permission. It can, however, be set unconditionally by a process with an appropriate authorisation token for instantiating a key, and can also be set by the key type driver when a key is instantiated, so lumping it with the access-controlling actions is probably okay. As for SEARCH permission, that currently covers: (1) Finding keys in a keyring tree during a search. (2) Permitting keyrings to be joined. (3) Invalidation. But these don't really belong together either, since these actions really need to be controlled separately. Finally, there are number of special cases to do with granting the administrator special rights to invalidate or clear keys that I would like to handle with the ACL rather than key flags and special checks. =============== WHAT IS CHANGED =============== The SETATTR permission is split to create two new permissions: (1) SET_SECURITY - which allows the key's owner, group and ACL to be changed and a restriction to be placed on a keyring. (2) REVOKE - which allows a key to be revoked. The SEARCH permission is split to create: (1) SEARCH - which allows a keyring to be search and a key to be found. (2) JOIN - which allows a keyring to be joined as a session keyring. (3) INVAL - which allows a key to be invalidated. The WRITE permission is also split to create: (1) WRITE - which allows a key's content to be altered and links to be added, removed and replaced in a keyring. (2) CLEAR - which allows a keyring to be cleared completely. This is split out to make it possible to give just this to an administrator. (3) REVOKE - see above. Keys acquire ACLs which consist of a series of ACEs, and all that apply are unioned together. An ACE specifies a subject, such as: (*) Possessor - permitted to anyone who 'possesses' a key (*) Owner - permitted to the key owner (*) Group - permitted to the key group (*) Everyone - permitted to everyone Note that 'Other' has been replaced with 'Everyone' on the assumption that you wouldn't grant a permit to 'Other' that you wouldn't also grant to everyone else. Further subjects may be made available by later patches. The ACE also specifies a permissions mask. The set of permissions is now: VIEW Can view the key metadata READ Can read the key content WRITE Can update/modify the key content SEARCH Can find the key by searching/requesting LINK Can make a link to the key SET_SECURITY Can change owner, ACL, expiry INVAL Can invalidate REVOKE Can revoke JOIN Can join this keyring CLEAR Can clear this keyring The KEYCTL_SETPERM function is then deprecated. The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set, or if the caller has a valid instantiation auth token. The KEYCTL_INVALIDATE function then requires INVAL. The KEYCTL_REVOKE function then requires REVOKE. The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an existing keyring. The JOIN permission is enabled by default for session keyrings and manually created keyrings only. ====================== BACKWARD COMPATIBILITY ====================== To maintain backward compatibility, KEYCTL_SETPERM will translate the permissions mask it is given into a new ACL for a key - unless KEYCTL_SET_ACL has been called on that key, in which case an error will be returned. It will convert possessor, owner, group and other permissions into separate ACEs, if each portion of the mask is non-zero. SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY. WRITE permission turns on WRITE, REVOKE and, if a keyring, CLEAR. JOIN is turned on if a keyring is being altered. The KEYCTL_DESCRIBE function translates the ACL back into a permissions mask to return depending on possessor, owner, group and everyone ACEs. It will make the following mappings: (1) INVAL, JOIN -> SEARCH (2) SET_SECURITY -> SETATTR (3) REVOKE -> WRITE if SETATTR isn't already set (4) CLEAR -> WRITE Note that the value subsequently returned by KEYCTL_DESCRIBE may not match the value set with KEYCTL_SETATTR. ======= TESTING ======= This passes the keyutils testsuite for all but a couple of tests: (1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed if the type doesn't have ->read(). You still can't actually read the key. (2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't work as Other has been replaced with Everyone in the ACL. Signed-off-by: David Howells <dhowells@redhat.com>
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#
b886d83c |
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01-Jun-2019 |
Thomas Gleixner <tglx@linutronix.de> |
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation version 2 of the license extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 315 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
221be106 |
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29-May-2019 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: check hash algorithm passed to init_desc() This patch prevents memory access beyond the evm_tfm array by checking the validity of the index (hash algorithm) passed to init_desc(). The hash algorithm can be arbitrarily set if the security.ima xattr type is not EVM_XATTR_HMAC. Fixes: 5feeb61183dde ("evm: Allow non-SHA1 digital signatures") Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
877b5691 |
|
14-Apr-2019 |
Eric Biggers <ebiggers@google.com> |
crypto: shash - remove shash_desc::flags The flags field in 'struct shash_desc' never actually does anything. The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP. However, no shash algorithm ever sleeps, making this flag a no-op. With this being the case, inevitably some users who can't sleep wrongly pass MAY_SLEEP. These would all need to be fixed if any shash algorithm actually started sleeping. For example, the shash_ahash_*() functions, which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP from the ahash API to the shash API. However, the shash functions are called under kmap_atomic(), so actually they're assumed to never sleep. Even if it turns out that some users do need preemption points while hashing large buffers, we could easily provide a helper function crypto_shash_update_large() which divides the data into smaller chunks and calls crypto_shash_update() and cond_resched() for each chunk. It's not necessary to have a flag in 'struct shash_desc', nor is it necessary to make individual shash algorithms aware of this at all. Therefore, remove shash_desc::flags, and document that the crypto_shash_*() functions can be called from any context. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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#
e7fde070 |
|
24-Jan-2019 |
Andy Shevchenko <andriy.shevchenko@linux.intel.com> |
evm: Use defined constant for UUID representation Instead of sizeof use pre-defined constant for UUID representation. While here, drop the implementation details of uuid_t type. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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#
876979c9 |
|
09-Dec-2018 |
Paul Gortmaker <paul.gortmaker@windriver.com> |
security: audit and remove any unnecessary uses of module.h 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>
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#
3d234b33 |
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14-Nov-2018 |
Eric Biggers <ebiggers@google.com> |
crypto: drop mask=CRYPTO_ALG_ASYNC from 'shash' tfm allocations '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>
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#
b2724d58 |
|
07-Sep-2018 |
Eric Biggers <ebiggers@google.com> |
security/integrity: constify some read-only data 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>
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#
5feeb611 |
|
08-Jun-2018 |
Matthew Garrett <mjg59@google.com> |
evm: Allow non-SHA1 digital signatures 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>
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#
e2861fa7 |
|
08-Jun-2018 |
Matthew Garrett <mjg59@google.com> |
evm: Don't deadlock if a crypto algorithm is unavailable 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>
|
#
fa516b66 |
|
15-May-2018 |
Matthew Garrett <mjg59@google.com> |
EVM: Allow runtime modification of the set of verified xattrs Sites may wish to provide additional metadata alongside files in order to make more fine-grained security decisions[1]. The security of this is enhanced if this metadata is protected, something that EVM makes possible. However, the kernel cannot know about the set of extended attributes that local admins may wish to protect, and hardcoding this policy in the kernel makes it difficult to change over time and less convenient for distributions to enable. This patch adds a new /sys/kernel/security/integrity/evm/evm_xattrs node, which can be read to obtain the current set of EVM-protected extended attributes or written to in order to add new entries. Extending this list will not change the validity of any existing signatures provided that the file in question does not have any of the additional extended attributes - missing xattrs are skipped when calculating the EVM hash. [1] For instance, a package manager could install information about the package uploader in an additional extended attribute. Local LSM policy could then be associated with that extended attribute in order to restrict the privileges available to packages from less trusted uploaders. Signed-off-by: Matthew Garrett <mjg59@google.com> Reviewed-by: James Morris <james.morris@microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
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#
21af7663 |
|
11-May-2018 |
Matthew Garrett <mjg59@google.com> |
EVM: turn evm_config_xattrnames into a list Use a list of xattrs rather than an array - this makes it easier to extend the list at runtime. Signed-off-by: Matthew Garrett <mjg59@google.com> Reviewed-by: James Morris <james.morris@microsoft.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
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#
a3a5c966 |
|
22-Dec-2017 |
Seth Forshee <seth.forshee@canonical.com> |
evm: Don't update hmacs in user ns mounts The kernel should not calculate new hmacs for mounts done by non-root users. Update evm_calc_hmac_or_hash() to refuse to calculate new hmacs for mounts for non-init user namespaces. Cc: linux-integrity@vger.kernel.org Cc: linux-security-module@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: James Morris <james.l.morris@oracle.com> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: "Serge E. Hallyn" <serge@hallyn.com> Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Dongsu Park <dongsu@kinvolk.io> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
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#
1a82cee3 |
|
27-Feb-2018 |
Hernán Gonzalez <hernan@vanguardiasur.com.ar> |
evm: Move evm_hmac and evm_hash from evm_main.c to evm_crypto.c These variables are not used where they are was defined. There is no point in declaring them there as extern. Move and constify them, saving 2 bytes. Function old new delta init_desc 273 271 -2 Total: Before=2112094, After=2112092, chg -0.00% Signed-off-by: Hernán Gonzalez <hernan@vanguardiasur.com.ar> Tested-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
|
#
50b97748 |
|
07-Nov-2017 |
Matthew Garrett <mjg59@google.com> |
EVM: Add support for portable signature format The EVM signature includes the inode number and (optionally) the filesystem UUID, making it impractical to ship EVM signatures in packages. This patch adds a new portable format intended to allow distributions to include EVM signatures. It is identical to the existing format but hardcodes the inode and generation numbers to 0 and does not include the filesystem UUID even if the kernel is configured to do so. Removing the inode means that the metadata and signature from one file could be copied to another file without invalidating it. This is avoided by ensuring that an IMA xattr is present during EVM validation. Portable signatures are intended to be immutable - ie, they will never be transformed into HMACs. Based on earlier work by Dmitry Kasatkin and Mikhail Kurinnoi. Signed-off-by: Matthew Garrett <mjg59@google.com> Cc: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Cc: Mikhail Kurinnoi <viewizard@viewizard.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
|
#
0485d066 |
|
11-Oct-2017 |
Matthew Garrett <mjg59@google.com> |
EVM: Only complain about a missing HMAC key once A system can validate EVM digital signatures without requiring an HMAC key, but every EVM validation will generate a kernel error. Change this so we only generate an error once. Signed-off-by: Matthew Garrett <mjg59@google.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
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#
85787090 |
|
10-May-2017 |
Christoph Hellwig <hch@lst.de> |
fs: switch ->s_uuid to uuid_t For some file systems we still memcpy into it, but in various places this already allows us to use the proper uuid helpers. More to come.. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Amir Goldstein <amir73il@gmail.com> Acked-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (Changes to IMA/EVM) Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
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#
19339c25 |
|
02-Dec-2016 |
Eric W. Biederman <ebiederm@xmission.com> |
Revert "evm: Translate user/group ids relative to s_user_ns when computing HMAC" This reverts commit 0b3c9761d1e405514a551ed24d3ea89aea26ce14. Seth Forshee <seth.forshee@canonical.com> writes: > All right, I think 0b3c9761d1e405514a551ed24d3ea89aea26ce14 should be > reverted then. EVM is a machine-local integrity mechanism, and so it > makes sense that the signature would be based on the kernel's notion of > the uid and not the filesystem's. I added a commment explaining why the EVM hmac needs to be in the kernel's notion of uid and gid, not the filesystems to prevent remounting the filesystem and gaining unwaranted trust in files. Acked-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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#
5d6c3191 |
|
29-Sep-2016 |
Andreas Gruenbacher <agruenba@redhat.com> |
xattr: Add __vfs_{get,set,remove}xattr helpers Right now, various places in the kernel check for the existence of getxattr, setxattr, and removexattr inode operations and directly call those operations. Switch to helper functions and test for the IOP_XATTR flag instead. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Acked-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
0b3c9761 |
|
05-Feb-2015 |
Seth Forshee <seth.forshee@canonical.com> |
evm: Translate user/group ids relative to s_user_ns when computing HMAC The EVM HMAC should be calculated using the on disk user and group ids, so the k[ug]ids in the inode must be translated relative to the s_user_ns of the inode's super block. Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
|
#
76266763 |
|
22-Oct-2015 |
Dmitry Kasatkin <dmitry.kasatkin@huawei.com> |
evm: provide a function to set the EVM key from the kernel A crypto HW kernel module can possibly initialize the EVM key from the kernel __init code to enable EVM before calling the 'init' process. This patch provides a function evm_set_key() to set the EVM key directly without using the KEY subsystem. Changes in v4: * kernel-doc style for evm_set_key Changes in v3: * error reporting moved to evm_set_key * EVM_INIT_HMAC moved to evm_set_key * added bitop to prevent key setting race Changes in v2: * use size_t for key size instead of signed int * provide EVM_MAX_KEY_SIZE macro in <linux/evm.h> * provide EVM_MIN_KEY_SIZE macro in <linux/evm.h> Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
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#
26ddabfe |
|
22-Oct-2015 |
Dmitry Kasatkin <dmitry.kasatkin@huawei.com> |
evm: enable EVM when X509 certificate is loaded In order to enable EVM before starting the 'init' process, evm_initialized needs to be non-zero. Previously non-zero indicated that the HMAC key was loaded. When EVM loads the X509 before calling 'init', with this patch it is now possible to enable EVM to start signature based verification. This patch defines bits to enable EVM if a key of any type is loaded. Changes in v3: * print error message if key is not set Changes in v2: * EVM_STATE_KEY_SET replaced by EVM_INIT_HMAC * EVM_STATE_X509_SET replaced by EVM_INIT_X509 Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
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#
146aa8b1 |
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21-Oct-2015 |
David Howells <dhowells@redhat.com> |
KEYS: Merge the type-specific data with the payload data Merge the type-specific data with the payload data into one four-word chunk as it seems pointless to keep them separate. Use user_key_payload() for accessing the payloads of overloaded user-defined keys. Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cifs@vger.kernel.org cc: ecryptfs@vger.kernel.org cc: linux-ext4@vger.kernel.org cc: linux-f2fs-devel@lists.sourceforge.net cc: linux-nfs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: linux-ima-devel@lists.sourceforge.net
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#
c6f493d6 |
|
17-Mar-2015 |
David Howells <dhowells@redhat.com> |
VFS: security/: d_backing_inode() annotations most of the ->d_inode uses there refer to the same inode IO would go to, i.e. d_backing_inode() Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
d3b33679 |
|
28-Mar-2014 |
Dmitry Kasatkin <d.kasatkin@samsung.com> |
evm: replace HMAC version with attribute mask Using HMAC version limits the posibility to arbitrarily add new attributes such as SMACK64EXEC to the hmac calculation. This patch replaces hmac version with attribute mask. Desired attributes can be enabled with configuration parameter. It allows to build kernels which works with previously labeled filesystems. Currently supported attribute is 'fsuuid' which is equivalent of the former version 2. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
|
#
627bf81a |
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01-Feb-2014 |
Al Viro <viro@zeniv.linux.org.uk> |
get rid of pointless checks for NULL ->i_op Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
#
2bb930ab |
|
04-Mar-2014 |
Dmitry Kasatkin <d.kasatkin@samsung.com> |
integrity: fix checkpatch errors Between checkpatch changes (eg. sizeof) and inconsistencies between Lindent and checkpatch, unfixed checkpatch errors make it difficult to see new errors. This patch fixes them. Some lines with over 80 chars remained unchanged to improve code readability. The "extern" keyword is removed from internal evm.h to make it consistent with internal ima.h. Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
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#
20ee451f |
|
24-Feb-2014 |
Joe Perches <joe@perches.com> |
security: integrity: Use a more current logging style Convert printks to pr_<level>. Add pr_fmt. Remove embedded prefixes. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
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#
74de6684 |
|
10-Sep-2012 |
Dmitry Kasatkin <dmitry.kasatkin@intel.com> |
evm: add file system uuid to EVM hmac EVM uses the same key for all file systems to calculate the HMAC, making it possible to paste inodes from one file system on to another one, without EVM being able to detect it. To prevent such an attack, it is necessary to make the EVM HMAC file system specific. This patch uses the file system UUID, a file system unique identifier, to bind the EVM HMAC to the file system. The value inode->i_sb->s_uuid is used for the HMAC hash calculation, instead of using it for deriving the file system specific key. Initializing the key for every inode HMAC calculation is a bit more expensive operation than adding the uuid to the HMAC hash. Changing the HMAC calculation method or adding additional info to the calculation, requires existing EVM labeled file systems to be relabeled. This patch adds a Kconfig HMAC version option for backwards compatability. Changelog v1: - squash "hmac version setting" Changelog v0: - add missing Kconfig depends (Mimi) Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
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#
a67adb99 |
|
18-Jan-2013 |
Dmitry Kasatkin <dmitry.kasatkin@intel.com> |
evm: checking if removexattr is not a NULL The following lines of code produce a kernel oops. fd = socket(PF_FILE, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); fchmod(fd, 0666); [ 139.922364] BUG: unable to handle kernel NULL pointer dereference at (null) [ 139.924982] IP: [< (null)>] (null) [ 139.924982] *pde = 00000000 [ 139.924982] Oops: 0000 [#5] SMP [ 139.924982] Modules linked in: fuse dm_crypt dm_mod i2c_piix4 serio_raw evdev binfmt_misc button [ 139.924982] Pid: 3070, comm: acpid Tainted: G D 3.8.0-rc2-kds+ #465 Bochs Bochs [ 139.924982] EIP: 0060:[<00000000>] EFLAGS: 00010246 CPU: 0 [ 139.924982] EIP is at 0x0 [ 139.924982] EAX: cf5ef000 EBX: cf5ef000 ECX: c143d600 EDX: c15225f2 [ 139.924982] ESI: cf4d2a1c EDI: cf4d2a1c EBP: cc02df10 ESP: cc02dee4 [ 139.924982] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 [ 139.924982] CR0: 80050033 CR2: 00000000 CR3: 0c059000 CR4: 000006d0 [ 139.924982] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 139.924982] DR6: ffff0ff0 DR7: 00000400 [ 139.924982] Process acpid (pid: 3070, ti=cc02c000 task=d7705340 task.ti=cc02c000) [ 139.924982] Stack: [ 139.924982] c1203c88 00000000 cc02def4 cf4d2a1c ae21eefa 471b60d5 1083c1ba c26a5940 [ 139.924982] e891fb5e 00000041 00000004 cc02df1c c1203964 00000000 cc02df4c c10e20c3 [ 139.924982] 00000002 00000000 00000000 22222222 c1ff2222 cf5ef000 00000000 d76efb08 [ 139.924982] Call Trace: [ 139.924982] [<c1203c88>] ? evm_update_evmxattr+0x5b/0x62 [ 139.924982] [<c1203964>] evm_inode_post_setattr+0x22/0x26 [ 139.924982] [<c10e20c3>] notify_change+0x25f/0x281 [ 139.924982] [<c10cbf56>] chmod_common+0x59/0x76 [ 139.924982] [<c10e27a1>] ? put_unused_fd+0x33/0x33 [ 139.924982] [<c10cca09>] sys_fchmod+0x39/0x5c [ 139.924982] [<c13f4f30>] syscall_call+0x7/0xb [ 139.924982] Code: Bad EIP value. This happens because sockets do not define the removexattr operation. Before removing the xattr, verify the removexattr function pointer is not NULL. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Signed-off-by: James Morris <james.l.morris@oracle.com>
|
#
cf9c9352 |
|
25-May-2012 |
Eric W. Biederman <ebiederm@xmission.com> |
userns: Convert EVM to deal with kuids and kgids in it's hmac computation Cc: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
|
#
97426f98 |
|
05-Dec-2011 |
Dmitry Kasatkin <dmitry.kasatkin@intel.com> |
evm: prevent racing during tfm allocation There is a small chance of racing during tfm allocation. This patch fixes it. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
|
#
d21b5945 |
|
05-Dec-2011 |
Dmitry Kasatkin <dmitry.kasatkin@intel.com> |
evm: key must be set once during initialization On multi-core systems, setting of the key before every caclculation, causes invalid HMAC calculation for other tfm users, because internal state (ipad, opad) can be invalid before set key call returns. It needs to be set only once during initialization. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
|
#
143b01d3 |
|
05-Dec-2011 |
Dmitry Kasatkin <dmitry.kasatkin@intel.com> |
evm: prevent racing during tfm allocation There is a small chance of racing during tfm allocation. This patch fixes it. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
|
#
88d7ed35 |
|
05-Dec-2011 |
Dmitry Kasatkin <dmitry.kasatkin@intel.com> |
evm: key must be set once during initialization On multi-core systems, setting of the key before every caclculation, causes invalid HMAC calculation for other tfm users, because internal state (ipad, opad) can be invalid before set key call returns. It needs to be set only once during initialization. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
|
#
15647eb3 |
|
01-Sep-2011 |
Dmitry Kasatkin <dmitry.kasatkin@intel.com> |
evm: digital signature verification support This patch adds support for digital signature verification to EVM. With this feature file metadata can be protected using digital signature instead of an HMAC. When building an image, which has to be flashed to different devices, an HMAC cannot be used to sign file metadata, because the HMAC key should be different on every device. Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Acked-by: Mimi Zohar <zohar@us.ibm.com>
|
#
d46eb369 |
|
09-Mar-2011 |
Dmitry Kasatkin <dmitry.kasatkin@nokia.com> |
evm: crypto hash replaced by shash Using shash is more efficient, because the algorithm is allocated only once. Only the descriptor to store the hash state needs to be allocated for every operation. Changelog v6: - check for crypto_shash_setkey failure Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
|
#
cb723180 |
|
09-Mar-2011 |
Mimi Zohar <zohar@linux.vnet.ibm.com> |
evm: add evm_inode_init_security to initialize new files Initialize 'security.evm' for new files. Changelog v7: - renamed evm_inode_post_init_security to evm_inode_init_security - moved struct xattr definition to earlier patch - allocate xattr name Changelog v6: - Use 'struct evm_ima_xattr_data' Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
|
#
6be5cc52 |
|
09-Mar-2011 |
Dmitry Kasatkin <dmitry.kasatkin@nokia.com> |
evm: add support for different security.evm data types EVM protects a file's security extended attributes(xattrs) against integrity attacks. The current patchset maintains an HMAC-sha1 value across the security xattrs, storing the value as the extended attribute 'security.evm'. We anticipate other methods for protecting the security extended attributes. This patch reserves the first byte of 'security.evm' as a place holder for the type of method. Changelog v6: - move evm_ima_xattr_type definition to security/integrity/integrity.h - defined a structure for the EVM xattr called evm_ima_xattr_data (based on Serge Hallyn's suggestion) - removed unnecessary memset Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com> Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
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66dbc325 |
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15-Mar-2011 |
Mimi Zohar <zohar@linux.vnet.ibm.com> |
evm: re-release EVM protects a file's security extended attributes(xattrs) against integrity attacks. This patchset provides the framework and an initial method. The initial method maintains an HMAC-sha1 value across the security extended attributes, storing the HMAC value as the extended attribute 'security.evm'. Other methods of validating the integrity of a file's metadata will be posted separately (eg. EVM-digital-signatures). While this patchset does authenticate the security xattrs, and cryptographically binds them to the inode, coming extensions will bind other directory and inode metadata for more complete protection. To help simplify the review and upstreaming process, each extension will be posted separately (eg. IMA-appraisal, IMA-appraisal-directory). For a general overview of the proposed Linux integrity subsystem, refer to Dave Safford's whitepaper: http://downloads.sf.net/project/linux-ima/linux-ima/Integrity_overview.pdf. EVM depends on the Kernel Key Retention System to provide it with a trusted/encrypted key for the HMAC-sha1 operation. The key is loaded onto the root's keyring using keyctl. Until EVM receives notification that the key has been successfully loaded onto the keyring (echo 1 > <securityfs>/evm), EVM can not create or validate the 'security.evm' xattr, but returns INTEGRITY_UNKNOWN. Loading the key and signaling EVM should be done as early as possible. Normally this is done in the initramfs, which has already been measured as part of the trusted boot. For more information on creating and loading existing trusted/encrypted keys, refer to Documentation/keys-trusted-encrypted.txt. A sample dracut patch, which loads the trusted/encrypted key and enables EVM, is available from http://linux-ima.sourceforge.net/#EVM. Based on the LSMs enabled, the set of EVM protected security xattrs is defined at compile. EVM adds the following three calls to the existing security hooks: evm_inode_setxattr(), evm_inode_post_setxattr(), and evm_inode_removexattr. To initialize and update the 'security.evm' extended attribute, EVM defines three calls: evm_inode_post_init(), evm_inode_post_setattr() and evm_inode_post_removexattr() hooks. To verify the integrity of a security xattr, EVM exports evm_verifyxattr(). Changelog v7: - Fixed URL in EVM ABI documentation Changelog v6: (based on Serge Hallyn's review) - fix URL in patch description - remove evm_hmac_size definition - use SHA1_DIGEST_SIZE (removed both MAX_DIGEST_SIZE and evm_hmac_size) - moved linux include before other includes - test for crypto_hash_setkey failure - fail earlier for invalid key - clear entire encrypted key, even on failure - check xattr name length before comparing xattr names Changelog: - locking based on i_mutex, remove evm_mutex - using trusted/encrypted keys for storing the EVM key used in the HMAC-sha1 operation. - replaced crypto hash with shash (Dmitry Kasatkin) - support for additional methods of verifying the security xattrs (Dmitry Kasatkin) - iint not allocated for all regular files, but only for those appraised - Use cap_sys_admin in lieu of cap_mac_admin - Use __vfs_setxattr_noperm(), without permission checks, from EVM Signed-off-by: Mimi Zohar <zohar@us.ibm.com> Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
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