[PATCH v3 2/4] add the buffer to the xattr

Prakhar Srivastava
2019-04-29T21:47:57Z

add the buffer to the xattr for a buffer case

Signed-off-by: Prakhar Srivastava <prsriva02@gmail.com>
---
security/integrity/ima/ima_main.c | 37 ++++++++++++++++++++---
security/integrity/ima/ima_template_lib.c | 3 +-
security/integrity/integrity.h | 1 +
3 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 3db3f3966ac7..7362952ab273 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -603,16 +603,37 @@ static int process_buffer_measurement(const void *buff, int size,
struct ima_digest_data hdr;
char digest[IMA_MAX_DIGEST_SIZE];
} hash;
+ struct buffer_xattr {
+ enum evm_ima_xattr_type type;
+ u16 buff_length;
+ unsigned char buff[0];
+ };
+
int violation = 0;
int pcr = CONFIG_IMA_MEASURE_PCR_IDX;
+ struct buffer_xattr *buffer_event_data = NULL;
+ int alloc_length = 0;
+ int action = 0;

if (!buff || size == 0 || !eventname)
goto err_out;

- if (ima_get_action(NULL, cred, secid, 0, BUFFER_CHECK, &pcr)
- != IMA_MEASURE)
+ action = ima_get_action(NULL, cred, secid, 0, BUFFER_CHECK, &pcr);
+ if (!(action & IMA_AUDIT) && !(action & IMA_MEASURE))
+ goto err_out;
+
+ alloc_length = sizeof(struct buffer_xattr) + size;
+ buffer_event_data = kzalloc(alloc_length, GFP_KERNEL);
+ if (!buffer_event_data)
goto err_out;

+ buffer_event_data->type = IMA_XATTR_BUFFER;
+ buffer_event_data->buff_length = size;
+ memcpy(buffer_event_data->buff, buff, size);
+
+ event_data.xattr_value = (struct evm_ima_xattr_data *)buffer_event_data;
+ event_data.xattr_len = alloc_length;
+
memset(iint, 0, sizeof(*iint));
memset(&hash, 0, sizeof(hash));

@@ -630,17 +651,23 @@ static int process_buffer_measurement(const void *buff, int size,
if (ret < 0)
goto err_out;

- ret = ima_store_template(entry, violation, NULL,
+ if (action & IMA_MEASURE)
+ ret = ima_store_template(entry, violation, NULL,
buff, pcr);
+
if (ret < 0) {
ima_free_template_entry(entry);
goto err_out;
}

- return 0;
+ if (action & IMA_AUDIT)
+ ima_audit_measurement(iint, event_data.filename);
+
+ ret = 0;

err_out:
- pr_err("Error in adding buffer measure: %d\n", ret);
+ kfree(buffer_event_data);
+ pr_debug("%s return: %d\n", __func__, ret);
return ret;
}

diff --git a/security/integrity/ima/ima_template_lib.c b/security/integrity/ima/ima_template_lib.c
index 513b457ae900..d22de3d8fcd9 100644
--- a/security/integrity/ima/ima_template_lib.c
+++ b/security/integrity/ima/ima_template_lib.c
@@ -383,7 +383,8 @@ int ima_eventsig_init(struct ima_event_data *event_data,
{
struct evm_ima_xattr_data *xattr_value = event_data->xattr_value;

- if ((!xattr_value) || (xattr_value->type != EVM_IMA_XATTR_DIGSIG))
+ if ((!xattr_value) || !((xattr_value->type == EVM_IMA_XATTR_DIGSIG) ||
+ (xattr_value->type == IMA_XATTR_BUFFER)))
return 0;

return ima_write_template_field_data(xattr_value, event_data->xattr_len,
diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h
index 7de59f44cba3..14ef904f091d 100644
--- a/security/integrity/integrity.h
+++ b/security/integrity/integrity.h
@@ -74,6 +74,7 @@ enum evm_ima_xattr_type {
EVM_IMA_XATTR_DIGSIG,
IMA_XATTR_DIGEST_NG,
EVM_XATTR_PORTABLE_DIGSIG,
+ IMA_XATTR_BUFFER,
IMA_XATTR_LAST
};

--
2.19.1