Re: [PATCH v1 2/6] KEYS: ima: Refactored process_buffer_measurement function so that it can measure any buffer (and not just KEXEC_CMDLINE one)
From: Mimi Zohar <zohar@linux.ibm.com>
Date: 2019-10-23 13:21:37
Also in:
keyrings, linux-integrity, lkml
On Tue, 2019-10-22 at 17:18 -0700, Lakshmi Ramasubramanian wrote:
quoted hunk ↗ jump to hunk
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 584019728660..8e965d18fb21 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c@@ -610,14 +610,14 @@ int ima_load_data(enum kernel_load_data_id id) * @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. - * @cred: a pointer to a credentials structure for user validation. - * @secid: the secid of the task to be validated. + * @pcr: pcr to extend the measurement + * @template_desc: template description * * Based on policy, the buffer is measured into the ima log. */ -static void process_buffer_measurement(const void *buf, int size, - const char *eventname, - const struct cred *cred, u32 secid) +void process_buffer_measurement(const void *buf, int size, + const char *eventname, int pcr, + struct ima_template_desc *template_desc) { int ret = 0; struct ima_template_entry *entry = NULL;@@ -626,19 +626,11 @@ static void process_buffer_measurement(const void *buf, int size, .filename = eventname, .buf = buf, .buf_len = size}; - struct ima_template_desc *template_desc = NULL; struct { struct ima_digest_data hdr; char digest[IMA_MAX_DIGEST_SIZE]; } hash = {}; int violation = 0; - int pcr = CONFIG_IMA_MEASURE_PCR_IDX; - int action = 0; - - action = ima_get_action(NULL, cred, secid, 0, KEXEC_CMDLINE, &pcr, - &template_desc); - if (!(action & IMA_MEASURE)) - return; iint.ima_hash = &hash.hdr; iint.ima_hash->algo = ima_hash_algo;
This patch is based on Nayna's version of this change, without any acknowledgment. Moving this code out of process_buffer_measurement is going to result in code duplication. Nayna has posted a newer version of this patch without the code duplication. As soon as she posts the patch with an updated patch description, I plan on picking up that version. Mimi
quoted hunk ↗ jump to hunk
@@ -670,12 +662,19 @@ static void process_buffer_measurement(const void *buf, int size, */ void ima_kexec_cmdline(const void *buf, int size) { + int pcr = CONFIG_IMA_MEASURE_PCR_IDX; + struct ima_template_desc *template_desc = ima_template_desc_current(); + int action; u32 secid; if (buf && size != 0) { security_task_getsecid(current, &secid); - process_buffer_measurement(buf, size, "kexec-cmdline", - current_cred(), secid); + action = ima_get_action(NULL, current_cred(), secid, 0, + KEXEC_CMDLINE, &pcr, &template_desc); + if (!(action & IMA_MEASURE)) + return; + process_buffer_measurement(buf, size, "kexec-cmdline", pcr, + template_desc); } }