[PATCH v3 3/3] dm crypt: log aead integrity violations to audit subsystem

[Michael Weiß]

Since dm-crypt target can be stacked on dm-integrity targets to
provide authenticated encryption, integrity violations are recognized
here during aead computation. We use the dm-audit submodule to
signal those events to user space, too.

The construction and destruction of crypt device mappings are also
logged as audit events.

Signed-off-by: Michael Weiß <michael.we...@aisec.fraunhofer.de>
---
 drivers/md/dm-crypt.c | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 50f4cbd600d5..5e02002345fa 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -41,6 +41,8 @@
 
 #include <linux/device-mapper.h>
 
+#include "dm-audit.h"
+
 #define DM_MSG_PREFIX "crypt"
 
 /*
@@ -1362,8 +1364,12 @@ static int crypt_convert_block_aead(struct crypt_config 
*cc,
 
        if (r == -EBADMSG) {
                char b[BDEVNAME_SIZE];
-               DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", 
bio_devname(ctx->bio_in, b),
-                           (unsigned long long)le64_to_cpu(*sector));
+               sector_t s = le64_to_cpu(*sector);
+
+               DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu",
+                           bio_devname(ctx->bio_in, b), s);
+               dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
+                                ctx->bio_in, s, 0);
        }
 
        if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
@@ -2173,8 +2179,12 @@ static void kcryptd_async_done(struct 
crypto_async_request *async_req,
 
        if (error == -EBADMSG) {
                char b[BDEVNAME_SIZE];
-               DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", 
bio_devname(ctx->bio_in, b),
-                           (unsigned long 
long)le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)));
+               sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq));
+
+               DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu",
+                           bio_devname(ctx->bio_in, b), s);
+               dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
+                                ctx->bio_in, s, 0);
                io->error = BLK_STS_PROTECTION;
        } else if (error < 0)
                io->error = BLK_STS_IOERR;
@@ -2729,6 +2739,8 @@ static void crypt_dtr(struct dm_target *ti)
        dm_crypt_clients_n--;
        crypt_calculate_pages_per_client();
        spin_unlock(&dm_crypt_clients_lock);
+
+       dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1);
 }
 
 static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode)
@@ -3357,9 +3369,11 @@ static int crypt_ctr(struct dm_target *ti, unsigned int 
argc, char **argv)
        ti->num_flush_bios = 1;
        ti->limit_swap_bios = true;
 
+       dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1);
        return 0;
 
 bad:
+       dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0);
        crypt_dtr(ti);
        return ret;
 }
-- 
2.20.1

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