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-rw-r--r--security/integrity/ima/ima_init.c97
1 files changed, 97 insertions, 0 deletions
diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c
new file mode 100644
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--- /dev/null
+++ b/security/integrity/ima/ima_init.c
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+/*
+ * Copyright (C) 2005,2006,2007,2008 IBM Corporation
+ *
+ * Authors:
+ * Reiner Sailer <sailer@watson.ibm.com>
+ * Leendert van Doorn <leendert@watson.ibm.com>
+ * Mimi Zohar <zohar@us.ibm.com>
+ *
+ * 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.
+ *
+ * File: ima_init.c
+ * initialization and cleanup functions
+ */
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include "ima.h"
+
+/* name for boot aggregate entry */
+static const char *boot_aggregate_name = "boot_aggregate";
+int ima_used_chip;
+
+/* Add the boot aggregate to the IMA measurement list and extend
+ * the PCR register.
+ *
+ * Calculate the boot aggregate, a SHA1 over tpm registers 0-7,
+ * assuming a TPM chip exists, and zeroes if the TPM chip does not
+ * exist. Add the boot aggregate measurement to the measurement
+ * list and extend the PCR register.
+ *
+ * If a tpm chip does not exist, indicate the core root of trust is
+ * not hardware based by invalidating the aggregate PCR value.
+ * (The aggregate PCR value is invalidated by adding one value to
+ * the measurement list and extending the aggregate PCR value with
+ * a different value.) Violations add a zero entry to the measurement
+ * list and extend the aggregate PCR value with ff...ff's.
+ */
+static void __init ima_add_boot_aggregate(void)
+{
+ struct ima_template_entry *entry;
+ const char *op = "add_boot_aggregate";
+ const char *audit_cause = "ENOMEM";
+ int result = -ENOMEM;
+ int violation = 1;
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ goto err_out;
+
+ memset(&entry->template, 0, sizeof(entry->template));
+ strncpy(entry->template.file_name, boot_aggregate_name,
+ IMA_EVENT_NAME_LEN_MAX);
+ if (ima_used_chip) {
+ violation = 0;
+ result = ima_calc_boot_aggregate(entry->template.digest);
+ if (result < 0) {
+ audit_cause = "hashing_error";
+ kfree(entry);
+ goto err_out;
+ }
+ }
+ result = ima_store_template(entry, violation, NULL);
+ if (result < 0)
+ kfree(entry);
+ return;
+err_out:
+ integrity_audit_msg(AUDIT_INTEGRITY_PCR, NULL, boot_aggregate_name, op,
+ audit_cause, result, 0);
+}
+
+int __init ima_init(void)
+{
+ u8 pcr_i[IMA_DIGEST_SIZE];
+ int rc;
+
+ ima_used_chip = 0;
+ rc = tpm_pcr_read(TPM_ANY_NUM, 0, pcr_i);
+ if (rc == 0)
+ ima_used_chip = 1;
+
+ if (!ima_used_chip)
+ pr_info("IMA: No TPM chip found, activating TPM-bypass!\n");
+
+ ima_add_boot_aggregate(); /* boot aggregate must be first entry */
+ ima_init_policy();
+
+ return ima_fs_init();
+}
+
+void __exit ima_cleanup(void)
+{
+ ima_fs_cleanup();
+}