[PATCH 27/38] xfs_db: compute hashes of merkle tree blocks

["Darrick J. Wong" <djwong@xxxxxxxxxx>]

From: Darrick J. Wong <djwong@xxxxxxxxxx>

Compute the hash of verity merkle tree blocks.

Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
 db/hash.c                |   21 +++++++++++++++++++--
 include/libxfs.h         |    1 +
 libxfs/libxfs_api_defs.h |    1 +
 man/man8/xfs_db.8        |    5 +++++
 4 files changed, 26 insertions(+), 2 deletions(-)


diff --git a/db/hash.c b/db/hash.c
index ab9c435b545f..e88d7d326bb5 100644
--- a/db/hash.c
+++ b/db/hash.c
@@ -36,7 +36,7 @@ hash_help(void)
 " 'hash' prints out the calculated hash value for a string using the\n"
 "directory/attribute code hash function.\n"
 "\n"
-" Usage:  \"hash [-d|-p parent_ino] <string>\"\n"
+" Usage:  \"hash [-d|-p parent_ino|-m merkle_blkno] <string>\"\n"
 "\n"
 ));
 
@@ -46,6 +46,7 @@ enum hash_what {
 	ATTR,
 	DIRECTORY,
 	PPTR,
+	MERKLE,
 };
 
 /* ARGSUSED */
@@ -54,16 +55,28 @@ hash_f(
 	int		argc,
 	char		**argv)
 {
+	struct xfs_merkle_key mk = { };
 	xfs_ino_t	p_ino = 0;
 	xfs_dahash_t	hashval;
+	unsigned long long mk_pos;
 	enum hash_what	what = ATTR;
 	int		c;
 
-	while ((c = getopt(argc, argv, "dp:")) != EOF) {
+	while ((c = getopt(argc, argv, "dm:p:")) != EOF) {
 		switch (c) {
 		case 'd':
 			what = DIRECTORY;
 			break;
+		case 'm':
+			errno = 0;
+			mk_pos = strtoull(optarg, NULL, 0);
+			if (errno) {
+				perror(optarg);
+				return 1;
+			}
+			mk.mk_pos = cpu_to_be64(mk_pos << XFS_VERITY_HASH_SHIFT);
+			what = MERKLE;
+			break;
 		case 'p':
 			errno = 0;
 			p_ino = strtoull(optarg, NULL, 0);
@@ -97,6 +110,10 @@ hash_f(
 		case ATTR:
 			hashval = libxfs_attr_hashname(xname.name, xname.len);
 			break;
+		case MERKLE:
+			hashval = libxfs_verity_hashname((void *)&mk, sizeof(mk));
+			break;
+
 		}
 		dbprintf("0x%x\n", hashval);
 	}
diff --git a/include/libxfs.h b/include/libxfs.h
index b4c6a2882aa3..0c3f0be85565 100644
--- a/include/libxfs.h
+++ b/include/libxfs.h
@@ -100,6 +100,7 @@ struct iomap;
 #include "xfs_rtgroup.h"
 #include "xfs_rtrmap_btree.h"
 #include "xfs_ag_resv.h"
+#include "xfs_verity.h"
 
 #ifndef ARRAY_SIZE
 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
diff --git a/libxfs/libxfs_api_defs.h b/libxfs/libxfs_api_defs.h
index 6ad728af2e0a..d125e2679348 100644
--- a/libxfs/libxfs_api_defs.h
+++ b/libxfs/libxfs_api_defs.h
@@ -394,6 +394,7 @@
 #define xfs_verify_fsbno		libxfs_verify_fsbno
 #define xfs_verify_ino			libxfs_verify_ino
 #define xfs_verify_rtbno		libxfs_verify_rtbno
+#define xfs_verity_hashname		libxfs_verity_hashname
 #define xfs_zero_extent			libxfs_zero_extent
 
 /* Please keep this list alphabetized. */
diff --git a/man/man8/xfs_db.8 b/man/man8/xfs_db.8
index 2c5aed2cf38c..deba4a6354aa 100644
--- a/man/man8/xfs_db.8
+++ b/man/man8/xfs_db.8
@@ -902,6 +902,11 @@ option is specified, the directory-specific hash function is used.
 This only makes a difference on filesystems with ascii case-insensitive
 lookups enabled.
 
+If the
+.B \-m
+option is specified, the merkle tree-specific hash function is used.
+The merkle tree block offset must be specified as an argument.
+
 If the
 .B \-p
 option is specified, the parent pointer-specific hash function is used.