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-rw-r--r--security/integrity/digsig.c4
-rw-r--r--security/integrity/evm/evm_crypto.c7
-rw-r--r--security/integrity/ima/ima.h8
-rw-r--r--security/integrity/ima/ima_api.c8
-rw-r--r--security/integrity/ima/ima_appraise.c2
-rw-r--r--security/integrity/ima/ima_asymmetric_keys.c2
-rw-r--r--security/integrity/ima/ima_init.c5
-rw-r--r--security/integrity/ima/ima_kexec.c3
-rw-r--r--security/integrity/ima/ima_main.c59
-rw-r--r--security/integrity/ima/ima_policy.c115
-rw-r--r--security/integrity/ima/ima_queue_keys.c3
-rw-r--r--security/selinux/Makefile2
-rw-r--r--security/selinux/ima.c44
-rw-r--r--security/selinux/include/ima.h24
-rw-r--r--security/selinux/include/security.h3
-rw-r--r--security/selinux/ss/services.c64
16 files changed, 301 insertions, 52 deletions
diff --git a/security/integrity/digsig.c b/security/integrity/digsig.c
index 0f518dcfde05..250fb0836156 100644
--- a/security/integrity/digsig.c
+++ b/security/integrity/digsig.c
@@ -143,8 +143,8 @@ out:
return __integrity_init_keyring(id, perm, restriction);
}
-int __init integrity_add_key(const unsigned int id, const void *data,
- off_t size, key_perm_t perm)
+static int __init integrity_add_key(const unsigned int id, const void *data,
+ off_t size, key_perm_t perm)
{
key_ref_t key;
int rc = 0;
diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
index 168c3b78ac47..a6dd47eb086d 100644
--- a/security/integrity/evm/evm_crypto.c
+++ b/security/integrity/evm/evm_crypto.c
@@ -73,7 +73,7 @@ static struct shash_desc *init_desc(char type, uint8_t hash_algo)
{
long rc;
const char *algo;
- struct crypto_shash **tfm, *tmp_tfm;
+ struct crypto_shash **tfm, *tmp_tfm = NULL;
struct shash_desc *desc;
if (type == EVM_XATTR_HMAC) {
@@ -118,13 +118,16 @@ unlock:
alloc:
desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(*tfm),
GFP_KERNEL);
- if (!desc)
+ if (!desc) {
+ crypto_free_shash(tmp_tfm);
return ERR_PTR(-ENOMEM);
+ }
desc->tfm = *tfm;
rc = crypto_shash_init(desc);
if (rc) {
+ crypto_free_shash(tmp_tfm);
kfree(desc);
return ERR_PTR(rc);
}
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 8e8b1e3cb847..aa312472c7c5 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -201,6 +201,7 @@ static inline unsigned int ima_hash_key(u8 *digest)
hook(POLICY_CHECK, policy) \
hook(KEXEC_CMDLINE, kexec_cmdline) \
hook(KEY_CHECK, key) \
+ hook(CRITICAL_DATA, critical_data) \
hook(MAX_CHECK, none)
#define __ima_hook_enumify(ENUM, str) ENUM,
@@ -256,7 +257,7 @@ static inline void ima_process_queued_keys(void) {}
int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
int mask, enum ima_hooks func, int *pcr,
struct ima_template_desc **template_desc,
- const char *keyring);
+ const char *func_data);
int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
int ima_collect_measurement(struct integrity_iint_cache *iint,
struct file *file, void *buf, loff_t size,
@@ -268,7 +269,8 @@ void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
struct ima_template_desc *template_desc);
void process_buffer_measurement(struct inode *inode, const void *buf, int size,
const char *eventname, enum ima_hooks func,
- int pcr, const char *keyring);
+ int pcr, const char *func_data,
+ bool buf_hash);
void ima_audit_measurement(struct integrity_iint_cache *iint,
const unsigned char *filename);
int ima_alloc_init_template(struct ima_event_data *event_data,
@@ -284,7 +286,7 @@ const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
enum ima_hooks func, int mask, int flags, int *pcr,
struct ima_template_desc **template_desc,
- const char *keyring);
+ const char *func_data);
void ima_init_policy(void);
void ima_update_policy(void);
void ima_update_policy_flag(void);
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 4f39fb93f278..1dd70dc68ffd 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -170,13 +170,13 @@ err_out:
* @func: caller identifier
* @pcr: pointer filled in if matched measure policy sets pcr=
* @template_desc: pointer filled in if matched measure policy sets template=
- * @keyring: keyring name used to determine the action
+ * @func_data: func specific data, may be NULL
*
* The policy is defined in terms of keypairs:
* subj=, obj=, type=, func=, mask=, fsmagic=
* subj,obj, and type: are LSM specific.
* func: FILE_CHECK | BPRM_CHECK | CREDS_CHECK | MMAP_CHECK | MODULE_CHECK
- * | KEXEC_CMDLINE | KEY_CHECK
+ * | KEXEC_CMDLINE | KEY_CHECK | CRITICAL_DATA
* mask: contains the permission mask
* fsmagic: hex value
*
@@ -186,14 +186,14 @@ err_out:
int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
int mask, enum ima_hooks func, int *pcr,
struct ima_template_desc **template_desc,
- const char *keyring)
+ const char *func_data)
{
int flags = IMA_MEASURE | IMA_AUDIT | IMA_APPRAISE | IMA_HASH;
flags &= ima_policy_flag;
return ima_match_policy(inode, cred, secid, func, mask, flags, pcr,
- template_desc, keyring);
+ template_desc, func_data);
}
/*
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 8361941ee0a1..46ffa38bab12 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -352,7 +352,7 @@ int ima_check_blacklist(struct integrity_iint_cache *iint,
if ((rc == -EPERM) && (iint->flags & IMA_MEASURE))
process_buffer_measurement(NULL, digest, digestsize,
"blacklisted-hash", NONE,
- pcr, NULL);
+ pcr, NULL, false);
}
return rc;
diff --git a/security/integrity/ima/ima_asymmetric_keys.c b/security/integrity/ima/ima_asymmetric_keys.c
index 1c68c500c26f..a74095793936 100644
--- a/security/integrity/ima/ima_asymmetric_keys.c
+++ b/security/integrity/ima/ima_asymmetric_keys.c
@@ -60,5 +60,5 @@ void ima_post_key_create_or_update(struct key *keyring, struct key *key,
*/
process_buffer_measurement(NULL, payload, payload_len,
keyring->description, KEY_CHECK, 0,
- keyring->description);
+ keyring->description, false);
}
diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c
index 4902fe7bd570..6e8742916d1d 100644
--- a/security/integrity/ima/ima_init.c
+++ b/security/integrity/ima/ima_init.c
@@ -15,6 +15,8 @@
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/err.h>
+#include <linux/ima.h>
+#include <generated/utsrelease.h>
#include "ima.h"
@@ -147,5 +149,8 @@ int __init ima_init(void)
ima_init_key_queue();
+ ima_measure_critical_data("kernel_info", "kernel_version",
+ UTS_RELEASE, strlen(UTS_RELEASE), false);
+
return rc;
}
diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c
index 121de3e04af2..e29bea3dd4cc 100644
--- a/security/integrity/ima/ima_kexec.c
+++ b/security/integrity/ima/ima_kexec.c
@@ -119,6 +119,7 @@ void ima_add_kexec_buffer(struct kimage *image)
ret = kexec_add_buffer(&kbuf);
if (ret) {
pr_err("Error passing over kexec measurement buffer.\n");
+ vfree(kexec_buffer);
return;
}
@@ -128,6 +129,8 @@ void ima_add_kexec_buffer(struct kimage *image)
return;
}
+ image->ima_buffer = kexec_buffer;
+
pr_debug("kexec measurement buffer for the loaded kernel at 0x%lx.\n",
kbuf.mem);
}
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index f87cb29329e9..6a429846f90a 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -809,20 +809,22 @@ int ima_post_load_data(char *buf, loff_t size,
}
/*
- * process_buffer_measurement - Measure the buffer to ima log.
+ * process_buffer_measurement - Measure the buffer or the buffer data hash
* @inode: inode associated with the object being measured (NULL for KEY_CHECK)
* @buf: pointer to the buffer that needs to be added to the log.
* @size: size of buffer(in bytes).
* @eventname: event name to be used for the buffer entry.
* @func: IMA hook
* @pcr: pcr to extend the measurement
- * @keyring: keyring name to determine the action to be performed
+ * @func_data: func specific data, may be NULL
+ * @buf_hash: measure buffer data hash
*
- * Based on policy, the buffer is measured into the ima log.
+ * Based on policy, either the buffer data or buffer data hash is measured
*/
void process_buffer_measurement(struct inode *inode, const void *buf, int size,
const char *eventname, enum ima_hooks func,
- int pcr, const char *keyring)
+ int pcr, const char *func_data,
+ bool buf_hash)
{
int ret = 0;
const char *audit_cause = "ENOMEM";
@@ -837,6 +839,8 @@ void process_buffer_measurement(struct inode *inode, const void *buf, int size,
struct ima_digest_data hdr;
char digest[IMA_MAX_DIGEST_SIZE];
} hash = {};
+ char digest_hash[IMA_MAX_DIGEST_SIZE];
+ int digest_hash_len = hash_digest_size[ima_hash_algo];
int violation = 0;
int action = 0;
u32 secid;
@@ -861,7 +865,7 @@ void process_buffer_measurement(struct inode *inode, const void *buf, int size,
if (func) {
security_task_getsecid(current, &secid);
action = ima_get_action(inode, current_cred(), secid, 0, func,
- &pcr, &template, keyring);
+ &pcr, &template, func_data);
if (!(action & IMA_MEASURE))
return;
}
@@ -879,13 +883,27 @@ void process_buffer_measurement(struct inode *inode, const void *buf, int size,
goto out;
}
+ if (buf_hash) {
+ memcpy(digest_hash, hash.hdr.digest, digest_hash_len);
+
+ ret = ima_calc_buffer_hash(digest_hash, digest_hash_len,
+ iint.ima_hash);
+ if (ret < 0) {
+ audit_cause = "hashing_error";
+ goto out;
+ }
+
+ event_data.buf = digest_hash;
+ event_data.buf_len = digest_hash_len;
+ }
+
ret = ima_alloc_init_template(&event_data, &entry, template);
if (ret < 0) {
audit_cause = "alloc_entry";
goto out;
}
- ret = ima_store_template(entry, violation, NULL, buf, pcr);
+ ret = ima_store_template(entry, violation, NULL, event_data.buf, pcr);
if (ret < 0) {
audit_cause = "store_entry";
ima_free_template_entry(entry);
@@ -920,10 +938,37 @@ void ima_kexec_cmdline(int kernel_fd, const void *buf, int size)
return;
process_buffer_measurement(file_inode(f.file), buf, size,
- "kexec-cmdline", KEXEC_CMDLINE, 0, NULL);
+ "kexec-cmdline", KEXEC_CMDLINE, 0, NULL,
+ false);
fdput(f);
}
+/**
+ * ima_measure_critical_data - measure kernel integrity critical data
+ * @event_label: unique event label for grouping and limiting critical data
+ * @event_name: event name for the record in the IMA measurement list
+ * @buf: pointer to buffer data
+ * @buf_len: length of buffer data (in bytes)
+ * @hash: measure buffer data hash
+ *
+ * Measure data critical to the integrity of the kernel into the IMA log
+ * and extend the pcr. Examples of critical data could be various data
+ * structures, policies, and states stored in kernel memory that can
+ * impact the integrity of the system.
+ */
+void ima_measure_critical_data(const char *event_label,
+ const char *event_name,
+ const void *buf, size_t buf_len,
+ bool hash)
+{
+ if (!event_name || !event_label || !buf || !buf_len)
+ return;
+
+ process_buffer_measurement(NULL, buf, buf_len, event_name,
+ CRITICAL_DATA, 0, event_label,
+ hash);
+}
+
static int __init init_ima(void)
{
int error;
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 823a0c1379cb..9b45d064a87d 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -34,6 +34,7 @@
#define IMA_PCR 0x0100
#define IMA_FSNAME 0x0200
#define IMA_KEYRINGS 0x0400
+#define IMA_LABEL 0x0800
#define UNKNOWN 0
#define MEASURE 0x0001 /* same as IMA_MEASURE */
@@ -85,6 +86,7 @@ struct ima_rule_entry {
} lsm[MAX_LSM_RULES];
char *fsname;
struct ima_rule_opt_list *keyrings; /* Measure keys added to these keyrings */
+ struct ima_rule_opt_list *label; /* Measure data grouped under this label */
struct ima_template_desc *template;
};
@@ -204,6 +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;
@@ -226,6 +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)
{
@@ -240,6 +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
@@ -453,30 +462,46 @@ int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
}
/**
- * ima_match_keyring - determine whether the keyring matches the measure rule
+ * ima_match_rule_data - determine whether func_data matches the policy rule
* @rule: a pointer to a rule
- * @keyring: name of the keyring to match against the measure rule
+ * @func_data: data to match against the measure rule data
* @cred: a pointer to a credentials structure for user validation
*
- * Returns true if keyring matches one in the rule, false otherwise.
+ * Returns true if func_data matches one in the rule, false otherwise.
*/
-static bool ima_match_keyring(struct ima_rule_entry *rule,
- const char *keyring, const struct cred *cred)
+static bool ima_match_rule_data(struct ima_rule_entry *rule,
+ const char *func_data,
+ const struct cred *cred)
{
+ const struct ima_rule_opt_list *opt_list = NULL;
bool matched = false;
size_t i;
if ((rule->flags & IMA_UID) && !rule->uid_op(cred->uid, rule->uid))
return false;
- if (!rule->keyrings)
- return true;
+ switch (rule->func) {
+ case KEY_CHECK:
+ if (!rule->keyrings)
+ return true;
+
+ opt_list = rule->keyrings;
+ break;
+ case CRITICAL_DATA:
+ if (!rule->label)
+ return true;
+
+ opt_list = rule->label;
+ break;
+ default:
+ return false;
+ }
- if (!keyring)
+ if (!func_data)
return false;
- for (i = 0; i < rule->keyrings->count; i++) {
- if (!strcmp(rule->keyrings->items[i], keyring)) {
+ for (i = 0; i < opt_list->count; i++) {
+ if (!strcmp(opt_list->items[i], func_data)) {
matched = true;
break;
}
@@ -493,24 +518,30 @@ static bool ima_match_keyring(struct ima_rule_entry *rule,
* @secid: the secid of the task to be validated
* @func: LIM hook identifier
* @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
- * @keyring: keyring name to check in policy for KEY_CHECK func
+ * @func_data: func specific data, may be NULL
*
* Returns true on rule match, false on failure.
*/
static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
const struct cred *cred, u32 secid,
enum ima_hooks func, int mask,
- const char *keyring)
+ const char *func_data)
{
int i;
- if (func == KEY_CHECK) {
- return (rule->flags & IMA_FUNC) && (rule->func == func) &&
- ima_match_keyring(rule, keyring, cred);
- }
if ((rule->flags & IMA_FUNC) &&
(rule->func != func && func != POST_SETATTR))
return false;
+
+ switch (func) {
+ case KEY_CHECK:
+ case CRITICAL_DATA:
+ return ((rule->func == func) &&
+ ima_match_rule_data(rule, func_data, cred));
+ default:
+ break;
+ }
+
if ((rule->flags & IMA_MASK) &&
(rule->mask != mask && func != POST_SETATTR))
return false;
@@ -610,8 +641,7 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
* @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
* @pcr: set the pcr to extend
* @template_desc: the template that should be used for this rule
- * @keyring: the keyring name, if given, to be used to check in the policy.
- * keyring can be NULL if func is anything other than KEY_CHECK.
+ * @func_data: func specific data, may be NULL
*
* Measure decision based on func/mask/fsmagic and LSM(subj/obj/type)
* conditions.
@@ -623,7 +653,7 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
enum ima_hooks func, int mask, int flags, int *pcr,
struct ima_template_desc **template_desc,
- const char *keyring)
+ const char *func_data)
{
struct ima_rule_entry *entry;
int action = 0, actmask = flags | (flags << 1);
@@ -638,7 +668,7 @@ int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
continue;
if (!ima_match_rules(entry, inode, cred, secid, func, mask,
- keyring))
+ func_data))
continue;
action |= entry->flags & IMA_ACTION_FLAGS;
@@ -848,6 +878,11 @@ 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();
}
@@ -907,7 +942,7 @@ enum {
Opt_uid_lt, Opt_euid_lt, Opt_fowner_lt,
Opt_appraise_type, Opt_appraise_flag,
Opt_permit_directio, Opt_pcr, Opt_template, Opt_keyrings,
- Opt_err
+ Opt_label, Opt_err
};
static const match_table_t policy_tokens = {
@@ -944,6 +979,7 @@ static const match_table_t policy_tokens = {
{Opt_pcr, "pcr=%s"},
{Opt_template, "template=%s"},
{Opt_keyrings, "keyrings=%s"},
+ {Opt_label, "label=%s"},
{Opt_err, NULL}
};
@@ -1107,6 +1143,18 @@ static bool ima_validate_rule(struct ima_rule_entry *entry)
return false;
break;
+ case CRITICAL_DATA:
+ if (entry->action & ~(MEASURE | DONT_MEASURE))
+ return false;
+
+ if (entry->flags & ~(IMA_FUNC | IMA_UID | IMA_PCR |
+ IMA_LABEL))
+ return false;
+
+ if (ima_rule_contains_lsm_cond(entry))
+ return false;
+
+ break;
default:
return false;
}
@@ -1238,6 +1286,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
else if (IS_ENABLED(CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS) &&
strcmp(args[0].from, "KEY_CHECK") == 0)
entry->func = KEY_CHECK;
+ else if (strcmp(args[0].from, "CRITICAL_DATA") == 0)
+ entry->func = CRITICAL_DATA;
else
result = -EINVAL;
if (!result)
@@ -1308,6 +1358,23 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
entry->flags |= IMA_KEYRINGS;
break;
+ case Opt_label:
+ ima_log_string(ab, "label", args[0].from);
+
+ if (entry->label) {
+ result = -EINVAL;
+ break;
+ }
+
+ entry->label = ima_alloc_rule_opt_list(args);
+ if (IS_ERR(entry->label)) {
+ result = PTR_ERR(entry->label);
+ entry->label = NULL;
+ break;
+ }
+
+ entry->flags |= IMA_LABEL;
+ break;
case Opt_fsuuid:
ima_log_string(ab, "fsuuid", args[0].from);
@@ -1688,6 +1755,12 @@ int ima_policy_show(struct seq_file *m, void *v)
seq_puts(m, " ");
}
+ if (entry->flags & IMA_LABEL) {
+ seq_puts(m, "label=");
+ ima_show_rule_opt_list(m, entry->label);
+ seq_puts(m, " ");
+ }
+
if (entry->flags & IMA_PCR) {
snprintf(tbuf, sizeof(tbuf), "%d", entry->pcr);
seq_printf(m, pt(Opt_pcr), tbuf);
diff --git a/security/integrity/ima/ima_queue_keys.c b/security/integrity/ima/ima_queue_keys.c
index 69a8626a35c0..c2f2ad34f9b7 100644
--- a/security/integrity/ima/ima_queue_keys.c
+++ b/security/integrity/ima/ima_queue_keys.c
@@ -162,7 +162,8 @@ void ima_process_queued_keys(void)
entry->payload_len,
entry->keyring_name,
KEY_CHECK, 0,
- entry->keyring_name);
+ entry->keyring_name,
+ false);
list_del(&entry->list);
ima_free_key_entry(entry);
}
diff --git a/security/selinux/Makefile b/security/selinux/Makefile
index 4d8e0e8adf0b..776162444882 100644
--- a/security/selinux/Makefile
+++ b/security/selinux/Makefile
@@ -16,6 +16,8 @@ selinux-$(CONFIG_NETLABEL) += netlabel.o
selinux-$(CONFIG_SECURITY_INFINIBAND) += ibpkey.o
+selinux-$(CONFIG_IMA) += ima.o
+
ccflags-y := -I$(srctree)/security/selinux -I$(srctree)/security/selinux/include
$(addprefix $(obj)/,$(selinux-y)): $(obj)/flask.h
diff --git a/security/selinux/ima.c b/security/selinux/ima.c
new file mode 100644
index 000000000000..03715893ff97
--- /dev/null
+++ b/security/selinux/ima.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2021 Microsoft Corporation
+ *
+ * Author: Lakshmi Ramasubramanian (nramas@linux.microsoft.com)
+ *
+ * Measure critical data structures maintainted by SELinux
+ * using IMA subsystem.
+ */
+#include <linux/vmalloc.h>
+#include <linux/ima.h>
+#include "security.h"
+#include "ima.h"
+
+/*
+ * selinux_ima_measure_state - Measure hash of the SELinux policy
+ *
+ * @state: selinux state struct
+ *
+ * NOTE: This function must be called with policy_mutex held.
+ */
+void selinux_ima_measure_state(struct selinux_state *state)
+{
+ void *policy = NULL;
+ size_t policy_len;
+ int rc = 0;
+
+ /*
+ * Measure SELinux policy only after initialization is completed.
+ */
+ if (!selinux_initialized(state))
+ return;
+
+ rc = security_read_state_kernel(state, &policy, &policy_len);
+ if (rc) {
+ pr_err("SELinux: %s: failed to read policy %d.\n", __func__, rc);
+ return;
+ }
+
+ ima_measure_critical_data("selinux", "selinux-policy-hash",
+ policy, policy_len, true);
+
+ vfree(policy);
+}
diff --git a/security/selinux/include/ima.h b/security/selinux/include/ima.h
new file mode 100644
index 000000000000..d69c36611423
--- /dev/null
+++ b/security/selinux/include/ima.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2021 Microsoft Corporation
+ *
+ * Author: Lakshmi Ramasubramanian (nramas@linux.microsoft.com)
+ *
+ * Measure critical data structures maintainted by SELinux
+ * using IMA subsystem.
+ */
+
+#ifndef _SELINUX_IMA_H_
+#define _SELINUX_IMA_H_
+
+#include "security.h"
+
+#ifdef CONFIG_IMA
+extern void selinux_ima_measure_state(struct selinux_state *selinux_state);
+#else
+static inline void selinux_ima_measure_state(struct selinux_state *selinux_state)
+{
+}
+#endif
+
+#endif /* _SELINUX_IMA_H_ */
diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index 765a258a899e..6fe25300b89d 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -229,7 +229,8 @@ void selinux_policy_cancel(struct selinux_state *state,
struct selinux_policy *policy);
int security_read_policy(struct selinux_state *state,
void **data, size_t *len);
-
+int security_read_state_kernel(struct selinux_state *state,
+ void **data, size_t *len);
int security_policycap_supported(struct selinux_state *state,
unsigned int req_cap);
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index 5e08ce2c5994..3438d0130378 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -65,6 +65,7 @@
#include "ebitmap.h"
#include "audit.h"
#include "policycap_names.h"
+#include "ima.h"
/* Forward declaration. */
static int context_struct_to_string(struct policydb *policydb,
@@ -2178,6 +2179,7 @@ static void selinux_notify_policy_change(struct selinux_state *state,
selinux_status_update_policyload(state, seqno);
selinux_netlbl_cache_invalidate();
selinux_xfrm_notify_policyload();
+ selinux_ima_measure_state(state);
}
void selinux_policy_commit(struct selinux_state *state,
@@ -3870,7 +3872,32 @@ out:
#endif /* CONFIG_NETLABEL */
/**
+ * __security_read_policy - read the policy.
+ * @policy: SELinux policy
+ * @data: binary policy data
+ * @len: length of data in bytes
+ *
+ */
+static int __security_read_policy(struct selinux_policy *policy,
+ void *data, size_t *len)
+{
+ int rc;
+ struct policy_file fp;
+
+ fp.data = data;
+ fp.len = *len;
+
+ rc = policydb_write(&policy->policydb, &fp);
+ if (rc)
+ return rc;
+
+ *len = (unsigned long)fp.data - (unsigned long)data;
+ return 0;
+}
+
+/**
* security_read_policy - read the policy.
+ * @state: selinux_state
* @data: binary policy data
* @len: length of data in bytes
*
@@ -3879,8 +3906,6 @@ int security_read_policy(struct selinux_state *state,
void **data, size_t *len)
{
struct selinux_policy *policy;
- int rc;
- struct policy_file fp;
policy = rcu_dereference_protected(
state->policy, lockdep_is_held(&state->policy_mutex));
@@ -3892,14 +3917,35 @@ int security_read_policy(struct selinux_state *state,
if (!*data)
return -ENOMEM;
- fp.data = *data;
- fp.len = *len;
+ return __security_read_policy(policy, *data, len);
+}
- rc = policydb_write(&policy->policydb, &fp);
- if (rc)
- return rc;
+/**
+ * security_read_state_kernel - read the policy.
+ * @state: selinux_state
+ * @data: binary policy data
+ * @len: length of data in bytes
+ *
+ * Allocates kernel memory for reading SELinux policy.
+ * This function is for internal use only and should not
+ * be used for returning data to user space.
+ *
+ * This function must be called with policy_mutex held.
+ */
+int security_read_state_kernel(struct selinux_state *state,
+ void **data, size_t *len)
+{
+ struct selinux_policy *policy;
- *len = (unsigned long)fp.data - (unsigned long)*data;
- return 0;
+ policy = rcu_dereference_protected(
+ state->policy, lockdep_is_held(&state->policy_mutex));
+ if (!policy)
+ return -EINVAL;
+
+ *len = policy->policydb.len;
+ *data = vmalloc(*len);
+ if (!*data)
+ return -ENOMEM;
+ return __security_read_policy(policy, *data, len);
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-11 11:37:00 +0000