linux/security/integrity/ima/ima_init.c, branch v3.13.2

ima: properly free ima_template_entry structures

2013-12-03T01:46:56Z

The new templates management mechanism records information associated to an event into an array of 'ima_field_data' structures and makes it available through the 'template_data' field of the 'ima_template_entry' structure (the element of the measurements list created by IMA). Since 'ima_field_data' contains dynamically allocated data (which length varies depending on the data associated to a selected template field), it is not enough to just free the memory reserved for a 'ima_template_entry' structure if something goes wrong. This patch creates the new function ima_free_template_entry() which walks the array of 'ima_field_data' structures, frees the memory referenced by the 'data' pointer and finally the space reserved for the 'ima_template_entry' structure. Further, it replaces existing kfree() that have a pointer to an 'ima_template_entry' structure as argument with calls to the new function. Fixes: a71dc65: ima: switch to new template management mechanism Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar

ima: Do not free 'entry' before it is initialized

2013-12-03T01:46:32Z

7bc5f447ce9d0 (ima: define new function ima_alloc_init_template() to API) moved the initialization of 'entry' in ima_add_boot_aggregate() a bit more below, after the if (ima_used_chip). So, 'entry' is not initialized while being inside this if-block. So, we should not attempt to free it. Found by Coverity (CID: 1131971) Fixes: 7bc5f447ce9d0 (ima: define new function ima_alloc_init_template() to API) Signed-off-by: Christoph Paasch Signed-off-by: Mimi Zohar

ima: extend the measurement list to include the file signature

2013-11-01T00:19:35Z

This patch defines a new template called 'ima-sig', which includes the file signature in the template data, in addition to the file's digest and pathname. A template is composed of a set of fields. Associated with each field is an initialization and display function. This patch defines a new template field called 'sig', the initialization function ima_eventsig_init(), and the display function ima_show_template_sig(). This patch modifies the .field_init() function definition to include the 'security.ima' extended attribute and length. Changelog: - remove unused code (Dmitry Kasatkin) - avoid calling ima_write_template_field_data() unnecesarily (Roberto Sassu) - rename DATA_FMT_SIG to DATA_FMT_HEX - cleanup ima_eventsig_init() based on Roberto's comments Signed-off-by: Mimi Zohar Signed-off-by: Dmitry Kasatkin Signed-off-by: Roberto Sassu

ima: new templates management mechanism

2013-10-25T21:17:04Z

The original 'ima' template is fixed length, containing the filedata hash and pathname. The filedata hash is limited to 20 bytes (md5/sha1). The pathname is a null terminated string, limited to 255 characters. To overcome these limitations and to add additional file metadata, it is necessary to extend the current version of IMA by defining additional templates. The main reason to introduce this feature is that, each time a new template is defined, the functions that generate and display the measurement list would include the code for handling a new format and, thus, would significantly grow over time. This patch set solves this problem by separating the template management from the remaining IMA code. The core of this solution is the definition of two new data structures: a template descriptor, to determine which information should be included in the measurement list, and a template field, to generate and display data of a given type. To define a new template field, developers define the field identifier and implement two functions, init() and show(), respectively to generate and display measurement entries. Initially, this patch set defines the following template fields (support for additional data types will be added later): - 'd': the digest of the event (i.e. the digest of a measured file), calculated with the SHA1 or MD5 hash algorithm; - 'n': the name of the event (i.e. the file name), with size up to 255 bytes; - 'd-ng': the digest of the event, calculated with an arbitrary hash algorithm (field format: [:]digest, where the digest prefix is shown only if the hash algorithm is not SHA1 or MD5); - 'n-ng': the name of the event, without size limitations. Defining a new template descriptor requires specifying the template format, a string of field identifiers separated by the '|' character. This patch set defines the following template descriptors: - "ima": its format is 'd|n'; - "ima-ng" (default): its format is 'd-ng|n-ng' Further details about the new template architecture can be found in Documentation/security/IMA-templates.txt. Changelog: - don't defer calling ima_init_template() - Mimi - don't define ima_lookup_template_desc() until used - Mimi - squashed with documentation patch - Mimi Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar

ima: define new function ima_alloc_init_template() to API

2013-10-25T21:17:04Z

Instead of allocating and initializing the template entry from multiple places (eg. boot aggregate, violation, and regular measurements), this patch defines a new function called ima_alloc_init_template(). The new function allocates and initializes the measurement entry with the inode digest and the filename. In respect to the current behavior, it truncates the file name passed in the 'filename' argument if the latter's size is greater than 255 bytes and the passed file descriptor is NULL. Changelog: - initialize 'hash' variable for non TPM case - Mimi - conform to expectation for 'iint' to be defined as a pointer. - Mimi - add missing 'file' dependency for recalculating file hash. - Mimi Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar

ima: pass the filename argument up to ima_add_template_entry()

2013-10-25T21:17:03Z

Pass the filename argument to ima_add_template_entry() in order to eliminate a dependency on template specific data (third argument of integrity_audit_msg). This change is required because, with the new template management mechanism, the generation of a new measurement entry will be performed by new specific functions (introduced in next patches) and the current IMA code will not be aware anymore of how data is stored in the entry payload. Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar

ima: ima_calc_boot_agregate must use SHA1

2013-10-25T21:17:02Z

With multiple hash algorithms, ima_hash_tfm is no longer guaranteed to be sha1. Need to force to use sha1. Changelog: - pass ima_digest_data to ima_calc_boot_aggregate() instead of char * (Roberto Sassu); - create an ima_digest_data structure in ima_add_boot_aggregate() (Roberto Sassu); - pass hash->algo to ima_alloc_tfm() (Roberto Sassu, reported by Dmitry). - "move hash definition in ima_add_boot_aggregate()" commit hunk to here. - sparse warning fix - Fengguang Wu Signed-off-by: Dmitry Kasatkin Signed-off-by: Roberto Sassu Signed-off-by: Mimi Zohar

ima: differentiate between template hash and file data hash sizes

2013-10-25T21:17:00Z

The TPM v1.2 limits the template hash size to 20 bytes. This patch differentiates between the template hash size, as defined in the ima_template_entry, and the file data hash size, as defined in the ima_template_data. Subsequent patches add support for different file data hash algorithms. Change log: - hash digest definition in ima_store_template() should be TPM_DIGEST_SIZE Signed-off-by: Mimi Zohar

ima: use new crypto_shash API instead of old crypto_hash

2013-02-06T15:41:12Z

Old crypto hash API internally uses shash API. Using shash API directly is more efficient. Signed-off-by: Dmitry Kasatkin Signed-off-by: Mimi Zohar

ima: remove unused cleanup functions

2012-07-02T20:43:30Z

IMA cannot be used as module and does not need __exit functions. Removed them. Signed-off-by: Dmitry Kasatkin Signed-off-by: Mimi Zohar