[PATCH v4 4/9] ima: serialize the binary_runtime_measurements

[Mimi Zohar]

The TPM PCRs are only reset on a hard reboot.  In order to validate a
TPM's quote after a soft reboot (eg. kexec -e), the IMA measurement list
of the running kernel must be saved and restored on boot.  This patch
serializes the IMA measurement list in the binary_runtime_measurements
format.

Signed-off-by: Mimi Zohar 
---
 security/integrity/ima/ima.h   |  1 +
 security/integrity/ima/ima_fs.c|  2 +-
 security/integrity/ima/ima_kexec.c | 51 ++
 3 files changed, 53 insertions(+), 1 deletion(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index f9cd08e..634d140 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -133,6 +133,7 @@ void ima_print_digest(struct seq_file *m, u8 *digest, u32 
size);
 struct ima_template_desc *ima_template_desc_current(void);
 int ima_restore_measurement_entry(struct ima_template_entry *entry);
 int ima_restore_measurement_list(loff_t bufsize, void *buf);
+int ima_measurements_show(struct seq_file *m, void *v);
 unsigned long ima_get_binary_runtime_size(void);
 int ima_init_template(void);
 
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index c07a384..66e5dd5 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c
@@ -116,7 +116,7 @@ void ima_putc(struct seq_file *m, void *data, int datalen)
  *   [eventdata length]
  *   eventdata[n]=template specific data
  */
-static int ima_measurements_show(struct seq_file *m, void *v)
+int ima_measurements_show(struct seq_file *m, void *v)
 {
/* the list never shrinks, so we don't need a lock here */
struct ima_queue_entry *qe = v;
diff --git a/security/integrity/ima/ima_kexec.c 
b/security/integrity/ima/ima_kexec.c
index 6a046ad..e77ca9d 100644
--- a/security/integrity/ima/ima_kexec.c
+++ b/security/integrity/ima/ima_kexec.c
@@ -23,6 +23,57 @@
 
 #include "ima.h"
 
+static int ima_dump_measurement_list(unsigned long *buffer_size, void **buffer,
+unsigned long segment_size)
+{
+   struct ima_queue_entry *qe;
+   struct seq_file file;
+   struct ima_kexec_hdr khdr = {
+   .version = 1, .buffer_size = 0, .count = 0};
+   int ret = 0;
+
+   /* segment size can't change between kexec load and execute */
+   file.buf = vmalloc(segment_size);
+   if (!file.buf) {
+   ret = -ENOMEM;
+   goto out;
+   }
+
+   file.size = segment_size;
+   file.read_pos = 0;
+   file.count = sizeof(khdr);  /* reserved space */
+
+   list_for_each_entry_rcu(qe, _measurements, later) {
+   if (file.count < file.size) {
+   khdr.count++;
+   ima_measurements_show(, qe);
+   } else {
+   ret = -EINVAL;
+   break;
+   }
+   }
+
+   if (ret < 0)
+   goto out;
+
+   /*
+* fill in reserved space with some buffer details
+* (eg. version, buffer size, number of measurements)
+*/
+   khdr.buffer_size = file.count;
+   memcpy(file.buf, , sizeof(khdr));
+   print_hex_dump(KERN_DEBUG, "ima dump: ", DUMP_PREFIX_NONE,
+   16, 1, file.buf,
+   file.count < 100 ? file.count : 100, true);
+
+   *buffer_size = file.count;
+   *buffer = file.buf;
+out:
+   if (ret == -EINVAL)
+   vfree(file.buf);
+   return ret;
+}
+
 /*
  * Restore the measurement list from the previous kernel.
  */
-- 
2.1.0

[PATCH v4 4/9] ima: serialize the binary_runtime_measurements

[Mimi Zohar]

The TPM PCRs are only reset on a hard reboot.  In order to validate a
TPM's quote after a soft reboot (eg. kexec -e), the IMA measurement list
of the running kernel must be saved and restored on boot.  This patch
serializes the IMA measurement list in the binary_runtime_measurements
format.

Signed-off-by: Mimi Zohar 
---
 security/integrity/ima/ima.h   |  1 +
 security/integrity/ima/ima_fs.c|  2 +-
 security/integrity/ima/ima_kexec.c | 51 ++
 3 files changed, 53 insertions(+), 1 deletion(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index f9cd08e..634d140 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -133,6 +133,7 @@ void ima_print_digest(struct seq_file *m, u8 *digest, u32 
size);
 struct ima_template_desc *ima_template_desc_current(void);
 int ima_restore_measurement_entry(struct ima_template_entry *entry);
 int ima_restore_measurement_list(loff_t bufsize, void *buf);
+int ima_measurements_show(struct seq_file *m, void *v);
 unsigned long ima_get_binary_runtime_size(void);
 int ima_init_template(void);
 
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index c07a384..66e5dd5 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c
@@ -116,7 +116,7 @@ void ima_putc(struct seq_file *m, void *data, int datalen)
  *   [eventdata length]
  *   eventdata[n]=template specific data
  */
-static int ima_measurements_show(struct seq_file *m, void *v)
+int ima_measurements_show(struct seq_file *m, void *v)
 {
/* the list never shrinks, so we don't need a lock here */
struct ima_queue_entry *qe = v;
diff --git a/security/integrity/ima/ima_kexec.c 
b/security/integrity/ima/ima_kexec.c
index 6a046ad..e77ca9d 100644
--- a/security/integrity/ima/ima_kexec.c
+++ b/security/integrity/ima/ima_kexec.c
@@ -23,6 +23,57 @@
 
 #include "ima.h"
 
+static int ima_dump_measurement_list(unsigned long *buffer_size, void **buffer,
+unsigned long segment_size)
+{
+   struct ima_queue_entry *qe;
+   struct seq_file file;
+   struct ima_kexec_hdr khdr = {
+   .version = 1, .buffer_size = 0, .count = 0};
+   int ret = 0;
+
+   /* segment size can't change between kexec load and execute */
+   file.buf = vmalloc(segment_size);
+   if (!file.buf) {
+   ret = -ENOMEM;
+   goto out;
+   }
+
+   file.size = segment_size;
+   file.read_pos = 0;
+   file.count = sizeof(khdr);  /* reserved space */
+
+   list_for_each_entry_rcu(qe, _measurements, later) {
+   if (file.count < file.size) {
+   khdr.count++;
+   ima_measurements_show(, qe);
+   } else {
+   ret = -EINVAL;
+   break;
+   }
+   }
+
+   if (ret < 0)
+   goto out;
+
+   /*
+* fill in reserved space with some buffer details
+* (eg. version, buffer size, number of measurements)
+*/
+   khdr.buffer_size = file.count;
+   memcpy(file.buf, , sizeof(khdr));
+   print_hex_dump(KERN_DEBUG, "ima dump: ", DUMP_PREFIX_NONE,
+   16, 1, file.buf,
+   file.count < 100 ? file.count : 100, true);
+
+   *buffer_size = file.count;
+   *buffer = file.buf;
+out:
+   if (ret == -EINVAL)
+   vfree(file.buf);
+   return ret;
+}
+
 /*
  * Restore the measurement list from the previous kernel.
  */
-- 
2.1.0