[PATCH] tpm: more bios log parsing fixes (44d7aff0) · Commits · 戴 / test

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>

drivers/char/tpm/tpm_bios.c

+4 −44

Original line number	Diff line number	Diff line
		@@ -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;
		}

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