| Message ID | 20201212180251.9943-8-tusharsu@linux.microsoft.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | IMA: support for measuring kernel integrity critical data | expand |
On Sat, 2020-12-12 at 10:02 -0800, Tushar Sugandhi wrote: > From: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> > > Define a new critical data builtin policy to allow measuring > early kernel integrity critical data before a custom IMA policy > is loaded. > > Add critical data to built-in IMA rules if the kernel command line > contains "ima_policy=critical_data". This sentence isn't really necessary. > > Update the documentation on kernel parameters to document > the new critical data builtin policy. > > Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> > Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com> Otherwise, Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> thanks, Mimi
On 2020-12-24 6:41 a.m., Mimi Zohar wrote: > On Sat, 2020-12-12 at 10:02 -0800, Tushar Sugandhi wrote: >> From: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> >> >> Define a new critical data builtin policy to allow measuring >> early kernel integrity critical data before a custom IMA policy >> is loaded. >> >> Add critical data to built-in IMA rules if the kernel command line >> contains "ima_policy=critical_data". > > This sentence isn't really necessary. > Will remove. >> >> Update the documentation on kernel parameters to document >> the new critical data builtin policy. >> >> Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com> >> Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com> > > Otherwise, > Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Thanks again for the "Reviewed-by" tag. Thanks, Tushar > > thanks, > > Mimi >
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 526d65d8573a..6034d75c3ca0 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1746,7 +1746,7 @@ ima_policy= [IMA] The builtin policies to load during IMA setup. Format: "tcb | appraise_tcb | secure_boot | - fail_securely" + fail_securely | critical_data" The "tcb" policy measures all programs exec'd, files mmap'd for exec, and all files opened with the read @@ -1765,6 +1765,9 @@ filesystems with the SB_I_UNVERIFIABLE_SIGNATURE flag. + The "critical_data" policy measures kernel integrity + critical data. + ima_tcb [IMA] Deprecated. Use ima_policy= instead. Load a policy which meets the needs of the Trusted Computing Base. This means IMA will measure all diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index fea996a9e26c..376b625acc72 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -206,6 +206,10 @@ static struct ima_rule_entry secure_boot_rules[] __ro_after_init = { .flags = IMA_FUNC | IMA_DIGSIG_REQUIRED}, }; +static struct ima_rule_entry critical_data_rules[] __ro_after_init = { + {.action = MEASURE, .func = CRITICAL_DATA, .flags = IMA_FUNC}, +}; + /* An array of architecture specific rules */ static struct ima_rule_entry *arch_policy_entry __ro_after_init; @@ -228,6 +232,7 @@ __setup("ima_tcb", default_measure_policy_setup); static bool ima_use_appraise_tcb __initdata; static bool ima_use_secure_boot __initdata; +static bool ima_use_critical_data __initdata; static bool ima_fail_unverifiable_sigs __ro_after_init; static int __init policy_setup(char *str) { @@ -242,6 +247,8 @@ static int __init policy_setup(char *str) ima_use_appraise_tcb = true; else if (strcmp(p, "secure_boot") == 0) ima_use_secure_boot = true; + else if (strcmp(p, "critical_data") == 0) + ima_use_critical_data = true; else if (strcmp(p, "fail_securely") == 0) ima_fail_unverifiable_sigs = true; else @@ -872,6 +879,11 @@ void __init ima_init_policy(void) ARRAY_SIZE(default_appraise_rules), IMA_DEFAULT_POLICY); + if (ima_use_critical_data) + add_rules(critical_data_rules, + ARRAY_SIZE(critical_data_rules), + IMA_DEFAULT_POLICY); + ima_update_policy_flag(); }