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author | 2016-01-14 20:59:14 -0500 | |
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committer | 2016-02-21 09:06:16 -0500 | |
commit | d9ddf077bb85b54200dfcb5f2edec4f0d6a7c2ca (patch) | |
tree | 1319aaa27cd27007ef02c076056be5d0268ee666 /security/integrity | |
parent | kexec: replace call to copy_file_from_fd() with kernel version (diff) | |
download | linux-d9ddf077bb85b54200dfcb5f2edec4f0d6a7c2ca.tar.gz linux-d9ddf077bb85b54200dfcb5f2edec4f0d6a7c2ca.tar.bz2 linux-d9ddf077bb85b54200dfcb5f2edec4f0d6a7c2ca.zip |
ima: support for kexec image and initramfs
Add IMA policy support for measuring/appraising the kexec image and
initramfs. Two new IMA policy identifiers KEXEC_KERNEL_CHECK and
KEXEC_INITRAMFS_CHECK are defined.
Example policy rules:
measure func=KEXEC_KERNEL_CHECK
appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig
measure func=KEXEC_INITRAMFS_CHECK
appraise func=KEXEC_INITRAMFS_CHECK appraise_type=imasig
Moving the enumeration to the vfs layer simplified the patches, allowing
the IMA changes, for the most part, to be separated from the other
changes. Unfortunately, passing either a kernel_read_file_id or a
ima_hooks enumeration within IMA is messy.
Option 1: duplicate kernel_read_file enumeration in ima_hooks
enum kernel_read_file_id {
...
READING_KEXEC_IMAGE,
READING_KEXEC_INITRAMFS,
READING_MAX_ID
enum ima_hooks {
...
KEXEC_KERNEL_CHECK
KEXEC_INITRAMFS_CHECK
Option 2: define ima_hooks as extension of kernel_read_file
eg: enum ima_hooks {
FILE_CHECK = READING_MAX_ID,
MMAP_CHECK,
In order to pass both kernel_read_file_id and ima_hooks values, we
would need to specify a struct containing a union.
struct caller_id {
union {
enum ima_hooks func_id;
enum kernel_read_file_id read_id;
};
};
Option 3: incorportate the ima_hooks enumeration into kernel_read_file_id,
perhaps changing the enumeration name.
For now, duplicate the new READING_KEXEC_IMAGE/INITRAMFS in the ima_hooks.
Changelog v4:
- replaced switch statement with a kernel_read_file_id to an ima_hooks
id mapping array - Dmitry
- renamed ima_hook tokens KEXEC_CHECK and INITRAMFS_CHECK to
KEXEC_KERNEL_CHECK and KEXEC_INITRAMFS_CHECK respectively - Dave Young
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Petko Manolov <petkan@mip-labs.com>
Acked-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Cc: Dave Young <dyoung@redhat.com>
Diffstat (limited to 'security/integrity')
-rw-r--r-- | security/integrity/ima/ima.h | 2 | ||||
-rw-r--r-- | security/integrity/ima/ima_main.c | 15 | ||||
-rw-r--r-- | security/integrity/ima/ima_policy.c | 17 |
3 files changed, 27 insertions, 7 deletions
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index a5d25921ee3c..bd97e0d290de 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -147,6 +147,8 @@ enum ima_hooks { POST_SETATTR, MODULE_CHECK, FIRMWARE_CHECK, + KEXEC_KERNEL_CHECK, + KEXEC_INITRAMFS_CHECK, MAX_CHECK }; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 5da0b9c00072..f76488162c1e 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -339,6 +339,13 @@ int ima_read_file(struct file *file, enum kernel_read_file_id read_id) return 0; } +static int read_idmap[READING_MAX_ID] = { + [READING_FIRMWARE] = FIRMWARE_CHECK, + [READING_MODULE] = MODULE_CHECK, + [READING_KEXEC_IMAGE] = KEXEC_KERNEL_CHECK, + [READING_KEXEC_INITRAMFS] = KEXEC_INITRAMFS_CHECK, +}; + /** * ima_post_read_file - in memory collect/appraise/audit measurement * @file: pointer to the file to be measured/appraised/audit @@ -355,7 +362,7 @@ int ima_read_file(struct file *file, enum kernel_read_file_id read_id) int ima_post_read_file(struct file *file, void *buf, loff_t size, enum kernel_read_file_id read_id) { - enum ima_hooks func = FILE_CHECK; + enum ima_hooks func; if (!file && read_id == READING_FIRMWARE) { if ((ima_appraise & IMA_APPRAISE_FIRMWARE) && @@ -373,11 +380,7 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size, return 0; } - if (read_id == READING_FIRMWARE) - func = FIRMWARE_CHECK; - else if (read_id == READING_MODULE) - func = MODULE_CHECK; - + func = read_idmap[read_id] ?: FILE_CHECK; return process_measurement(file, buf, size, MAY_READ, func, 0); } diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 7571ce8841ff..646134cdf3e8 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -612,6 +612,12 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry) entry->func = MMAP_CHECK; else if (strcmp(args[0].from, "BPRM_CHECK") == 0) entry->func = BPRM_CHECK; + else if (strcmp(args[0].from, "KEXEC_KERNEL_CHECK") == + 0) + entry->func = KEXEC_KERNEL_CHECK; + else if (strcmp(args[0].from, "KEXEC_INITRAMFS_CHECK") + == 0) + entry->func = KEXEC_INITRAMFS_CHECK; else result = -EINVAL; if (!result) @@ -855,7 +861,8 @@ static char *mask_tokens[] = { enum { func_file = 0, func_mmap, func_bprm, - func_module, func_firmware, func_post + func_module, func_firmware, func_post, + func_kexec_kernel, func_kexec_initramfs }; static char *func_tokens[] = { @@ -864,6 +871,8 @@ static char *func_tokens[] = { "BPRM_CHECK", "MODULE_CHECK", "FIRMWARE_CHECK", + "KEXEC_KERNEL_CHECK", + "KEXEC_INITRAMFS_CHECK", "POST_SETATTR" }; @@ -929,6 +938,12 @@ static void policy_func_show(struct seq_file *m, enum ima_hooks func) case POST_SETATTR: seq_printf(m, pt(Opt_func), ft(func_post)); break; + case KEXEC_KERNEL_CHECK: + seq_printf(m, pt(Opt_func), ft(func_kexec_kernel)); + break; + case KEXEC_INITRAMFS_CHECK: + seq_printf(m, pt(Opt_func), ft(func_kexec_initramfs)); + break; default: snprintf(tbuf, sizeof(tbuf), "%d", func); seq_printf(m, pt(Opt_func), tbuf); |