[PATCH] tpm: more bios log parsing fixes

From: Seiji Munetoh <seiji.munetoh@gmail.com>

Change the binary output format to actual ACPI TCPA log structure since the
current format does not contain all event-data information that need to
verify the PCRs in TPM.  tpm_binary_bios_measurements_show() uses
get_event_name() to convert the binary event-data to ascii format, and puts
them as binary.  However, to verify the PCRs, the event-data must be a
actual binary event-data used by SHA1 calc.  in BIOS.

So, I think actual ACPI TCPA log is good for this binary output format.
That way, any userland tools easily parse this data with reference to TCG
PC specification.

Signed-off-by: Seiji Munetoh <seiji.munetoh@gmail.com>
Acked-by: Kylene Hall <kjhall@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/char/tpm/tpm_bios.c b/drivers/char/tpm/tpm_bios.c
index 6038017..a611972 100644 (file)
--- a/drivers/char/tpm/tpm_bios.c
+++ b/drivers/char/tpm/tpm_bios.c
@@ -284,53 +284,13 @@ static int get_event_name(char *dest, struct tcpa_event *event,
 
 static int tpm_binary_bios_measurements_show(struct seq_file *m, void *v)
 {
+       struct tcpa_event *event = v;
+       char *data = v;
+       int i;
 
-       char *eventname;
-       char data[4];
-       u32 help;
-       int i, len;
-       struct tcpa_event *event = (struct tcpa_event *) v;
-       unsigned char *event_entry =
-           (unsigned char *) (v + sizeof(struct tcpa_event));
-
-       eventname = kmalloc(MAX_TEXT_EVENT, GFP_KERNEL);
-       if (!eventname) {
-               printk(KERN_ERR "%s: ERROR - No Memory for event name\n ",
-                      __func__);
-               return -ENOMEM;
-       }
-
-       /* 1st: PCR used is in little-endian format (4 bytes) */
-       help = le32_to_cpu(event->pcr_index);
-       memcpy(data, &help, 4);
-       for (i = 0; i < 4; i++)
-               seq_putc(m, data[i]);
-
-       /* 2nd: SHA1 (20 bytes) */
-       for (i = 0; i < 20; i++)
-               seq_putc(m, event->pcr_value[i]);
-
-       /* 3rd: event type identifier (4 bytes) */
-       help = le32_to_cpu(event->event_type);
-       memcpy(data, &help, 4);
-       for (i = 0; i < 4; i++)
+       for (i = 0; i < sizeof(struct tcpa_event) + event->event_size; i++)
                seq_putc(m, data[i]);
 
-       len = 0;
-
-       len += get_event_name(eventname, event, event_entry);
-
-       /* 4th:  filename <= 255 + \'0' delimiter */
-       if (len > TCG_EVENT_NAME_LEN_MAX)
-               len = TCG_EVENT_NAME_LEN_MAX;
-
-       for (i = 0; i < len; i++)
-               seq_putc(m, eventname[i]);
-
-       /* 5th: delimiter */
-       seq_putc(m, '\0');
-
-       kfree(eventname);
        return 0;
 }