ubifs: Add hashes and HMACs to default filesystem

This patch calculates the necessary hashes and HMACs for the default
filesystem so that the dynamically created default fs can be
authenticated.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

1 files changed, 27 insertions, 7 deletions

diff --git a/fs/ubifs/sb.c b/fs/ubifs/sb.c
index 7f0967771c9f..ac1ed5ad126d 100644
--- a/fs/ubifs/sb.c
+++ b/fs/ubifs/sb.c
@@ -87,6 +87,7 @@ static int create_default_filesystem(struct ubifs_info *c)
         __le64 tmp_le64;
         __le32 tmp_le32;
         struct timespec64 ts;
+        u8 hash[UBIFS_HASH_ARR_SZ];
         u8 hash_lpt[UBIFS_HASH_ARR_SZ];
 
         /* Some functions called from here depend on the @c->key_len filed */
@@ -177,6 +178,16 @@ static int create_default_filesystem(struct ubifs_info *c)
                 sup_flags |= UBIFS_FLG_BIGLPT;
         sup_flags |= UBIFS_FLG_DOUBLE_HASH;
 
+        if (ubifs_authenticated(c)) {
+                sup_flags |= UBIFS_FLG_AUTHENTICATION;
+                sup->hash_algo = cpu_to_le16(c->auth_hash_algo);
+                err = ubifs_hmac_wkm(c, sup->hmac_wkm);
+                if (err)
+                        goto out;
+        } else {
+                sup->hash_algo = 0xffff;
+        }
+
         sup->ch.node_type  = UBIFS_SB_NODE;
         sup->key_hash      = UBIFS_KEY_HASH_R5;
         sup->flags         = cpu_to_le32(sup_flags);
@@ -235,6 +246,7 @@ static int create_default_filesystem(struct ubifs_info *c)
         mst->empty_lebs   = cpu_to_le32(main_lebs - 2);
         mst->idx_lebs     = cpu_to_le32(1);
         mst->leb_cnt      = cpu_to_le32(c->leb_cnt);
+        ubifs_copy_hash(c, hash_lpt, mst->hash_lpt);
 
         /* Calculate lprops statistics */
         tmp64 = main_bytes;
@@ -307,25 +319,33 @@ static int create_default_filesystem(struct ubifs_info *c)
 
         cs->ch.node_type = UBIFS_CS_NODE;
 
-        err = ubifs_write_node(c, sup, UBIFS_SB_NODE_SZ, 0, 0);
+        err = ubifs_write_node_hmac(c, sup, UBIFS_SB_NODE_SZ, 0, 0,
+                                    offsetof(struct ubifs_sb_node, hmac));
         if (err)
                 goto out;
 
-        err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0);
+        err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ,
+                               main_first + DEFAULT_DATA_LEB, 0);
         if (err)
                 goto out;
 
-        err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1,
-                               0);
+        ubifs_node_calc_hash(c, ino, hash);
+        ubifs_copy_hash(c, hash, ubifs_branch_hash(c, br));
+
+        err = ubifs_write_node(c, idx, idx_node_size, main_first + DEFAULT_IDX_LEB, 0);
         if (err)
                 goto out;
 
-        err = ubifs_write_node(c, idx, idx_node_size, main_first + DEFAULT_IDX_LEB, 0);
+        ubifs_node_calc_hash(c, idx, hash);
+        ubifs_copy_hash(c, hash, mst->hash_root_idx);
+
+        err = ubifs_write_node_hmac(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0,
+                offsetof(struct ubifs_mst_node, hmac));
         if (err)
                 goto out;
 
-        err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ,
-                               main_first + DEFAULT_DATA_LEB, 0);
+        err = ubifs_write_node_hmac(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1,
+                               0, offsetof(struct ubifs_mst_node, hmac));
         if (err)
                 goto out;