mkfs.ubifs: Implement filename encryption

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

diff --git a/ubifs-utils/mkfs.ubifs/key.h b/ubifs-utils/mkfs.ubifs/key.h
index 0c7922b67687b7282252daab75eabd8907f373ec..c18e35e8f0a39f742c426f53d761e36617a0514c 100644 (file)
--- a/ubifs-utils/mkfs.ubifs/key.h
+++ b/ubifs-utils/mkfs.ubifs/key.h
@@ -110,9 +110,9 @@ static inline void ino_key_init(union ubifs_key *key, ino_t inum)
  */
 static inline void dent_key_init(const struct ubifs_info *c,
                                 union ubifs_key *key, ino_t inum,
-                                const struct qstr *nm)
+                                const void *name, int name_len)
 {
-       uint32_t hash = c->key_hash(nm->name, nm->len);
+       uint32_t hash = c->key_hash(name, name_len);
 
        assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
        key->u32[0] = inum;

diff --git a/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c b/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c
index 469d5874eaa2d3f133d49be8c6a27935b6a425b5..7deca96e79539dbcc016e5993e404dad575464a8 100644 (file)
--- a/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c
+++ b/ubifs-utils/mkfs.ubifs/mkfs.ubifs.c
@@ -1596,6 +1596,7 @@ static int add_dent_node(ino_t dir_inum, const char *name, ino_t inum,
        union ubifs_key key;
        struct qstr dname;
        char *kname;
+       int kname_len;
        int len;
 
        dbg_msg(3, "%s ino %lu type %u dir ino %lu", name, (unsigned long)inum,
@@ -1607,23 +1608,61 @@ static int add_dent_node(ino_t dir_inum, const char *name, ino_t inum,
 
        dent->ch.node_type = UBIFS_DENT_NODE;
 
-       dent_key_init(c, &key, dir_inum, &dname);
-       key_write(&key, dent->key);
        dent->inum = cpu_to_le64(inum);
        dent->padding1 = 0;
        dent->type = type;
-       dent->nlen = cpu_to_le16(dname.len);
-       memcpy(dent->name, dname.name, dname.len);
-       dent->name[dname.len] = '\0';
        set_dent_cookie(dent);
 
-       len = UBIFS_DENT_NODE_SZ + dname.len + 1;
-
-       kname = strdup(name);
-       if (!kname)
-               return err_msg("cannot allocate memory");
+       if (!fctx) {
+               dent_key_init(c, &key, dir_inum, dname.name, dname.len);
+               dent->nlen = cpu_to_le16(dname.len);
+               memcpy(dent->name, dname.name, dname.len);
+               dent->name[dname.len] = '\0';
+               len = UBIFS_DENT_NODE_SZ + dname.len + 1;
+
+               kname_len = dname.len;
+               kname = strdup(name);
+               if (!kname)
+                       return err_msg("cannot allocate memory");
+       } else {
+               void *inbuf, *outbuf, *crypt_key;
+               unsigned int max_namelen = type == UBIFS_ITYPE_LNK ? UBIFS_MAX_INO_DATA : UBIFS_MAX_NLEN;
+               unsigned int padding = 4 << (fctx->flags & FS_POLICY_FLAGS_PAD_MASK);
+               unsigned int cryptlen;
+
+               cryptlen = max_t(unsigned int, dname.len, FS_CRYPTO_BLOCK_SIZE);
+               cryptlen = round_up(cryptlen, padding);
+               cryptlen = min(cryptlen, max_namelen);
+
+               inbuf = xmalloc(cryptlen);
+               outbuf = xmalloc(cryptlen + 32);
+
+               memset(inbuf, 0, cryptlen);
+               memcpy(inbuf, dname.name, dname.len);
+
+               crypt_key = calc_fscrypt_subkey(fctx);
+               if (!crypt_key)
+                       return err_msg("could not compute subkey");
+               if (encrypt_aes128_cbc_cts(inbuf, cryptlen, crypt_key, outbuf) < 0)
+                       return err_msg("could not encrypt filename");
+
+               dent->nlen = cpu_to_le16(cryptlen);
+               memcpy(dent->name, outbuf, cryptlen);
+               dent->name[cryptlen] = '\0';
+               len = UBIFS_DENT_NODE_SZ + cryptlen + 1;
+
+               dent_key_init(c, &key, dir_inum, outbuf, cryptlen);
+
+               kname_len = cryptlen;
+               kname = xmalloc(cryptlen);
+               memcpy(kname, outbuf, cryptlen);
+               free(crypt_key);
+               free(inbuf);
+               free(outbuf);
+       }
+       key_write(&key, dent->key);
 
-       return add_node(&key, kname, dname.len, dent, len);
+       return add_node(&key, kname, kname_len, dent, len);
 }
 
 /**