smbd: Convert smb2_posix_cc_info() to use an existing blob

Less malloc

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>

diff --git a/source3/smbd/proto.h b/source3/smbd/proto.h
index a0870089925dcd2c7cfe833e9cfe938097ef1256..4c92913a6daf31df1e265f58dbecf7131a5dc9c7 100644 (file)
--- a/source3/smbd/proto.h
+++ b/source3/smbd/proto.h
@@ -1258,10 +1258,14 @@ NTSTATUS vfs_default_durable_reconnect(struct connection_struct *conn,
                                       DATA_BLOB *new_cookie);
 
 /* The following definitions come from smbd/smb2_posix.c */
-DATA_BLOB smb2_posix_cc_info(TALLOC_CTX *mem_ctx,
-                               connection_struct *conn,
-                               uint32_t reparse_tag,
-                               const SMB_STRUCT_STAT *psbuf);
+ssize_t smb2_posix_cc_info(
+       connection_struct *conn,
+       uint32_t reparse_tag,
+       const SMB_STRUCT_STAT *psbuf,
+       const struct dom_sid *owner,
+       const struct dom_sid *group,
+       uint8_t *buf,
+       size_t buflen);
 DATA_BLOB store_smb2_posix_info(TALLOC_CTX *mem_ctx,
                                connection_struct *conn,
                                const SMB_STRUCT_STAT *psbuf,

diff --git a/source3/smbd/smb2_posix.c b/source3/smbd/smb2_posix.c
index 3d9e2a617e48085758035b14de5d5b86a613197e..54b5e87845d799111b9fad78623f3d72b24a7509 100644 (file)
--- a/source3/smbd/smb2_posix.c
+++ b/source3/smbd/smb2_posix.c
@@ -25,61 +25,60 @@
 /*
  * SMB2 POSIX create context return details.
  */
-DATA_BLOB smb2_posix_cc_info(TALLOC_CTX *mem_ctx,
-                               connection_struct *conn,
-                               uint32_t reparse_tag,
-                               const SMB_STRUCT_STAT *psbuf)
+ssize_t smb2_posix_cc_info(
+       connection_struct *conn,
+       uint32_t reparse_tag,
+       const SMB_STRUCT_STAT *psbuf,
+       const struct dom_sid *owner,
+       const struct dom_sid *group,
+       uint8_t *buf,
+       size_t buflen)
 {
-       DATA_BLOB ret_blob = data_blob_null;
-       struct dom_sid sid_owner;
-       struct dom_sid sid_group;
-       size_t owner_sid_size = 0;
-       size_t group_sid_size = 0;
+       size_t owner_sid_size = ndr_size_dom_sid(owner, 0);
+       size_t group_sid_size = ndr_size_dom_sid(group, 0);
        size_t b_size = 12;
 
-       uid_to_sid(&sid_owner, psbuf->st_ex_uid);
-       owner_sid_size = ndr_size_dom_sid(&sid_owner, 0);
+       owner_sid_size = ndr_size_dom_sid(owner, 0);
        if (b_size + owner_sid_size < b_size) {
-               return data_blob_null;
+               return -1;
        }
        b_size += owner_sid_size;
 
-       gid_to_sid(&sid_group, psbuf->st_ex_gid);
-       group_sid_size = ndr_size_dom_sid(&sid_group, 0);
+       group_sid_size = ndr_size_dom_sid(group, 0);
        if (b_size + group_sid_size < b_size) {
-               return data_blob_null;
+               return -1;
        }
        b_size += group_sid_size;
 
-       ret_blob = data_blob_talloc(mem_ctx,
-                                   NULL,
-                                   b_size);
-       if (ret_blob.data == NULL) {
-               return data_blob_null;
+       if (buflen < b_size) {
+               return b_size;
        }
 
        /* number of hard links */
-       PUSH_LE_U32(ret_blob.data, 0, psbuf->st_ex_nlink);
+       PUSH_LE_U32(buf, 0, psbuf->st_ex_nlink);
 
        /* Reparse tag if FILE_FLAG_REPARSE is set, else zero. */
-       PUSH_LE_U32(ret_blob.data, 4, reparse_tag);
+       PUSH_LE_U32(buf, 4, reparse_tag);
 
        /*
         * Remove type info from mode, leaving only the
         * permissions and setuid/gid bits.
         */
-       PUSH_LE_U32(ret_blob.data,
+       PUSH_LE_U32(buf,
                    8,
                    unix_perms_to_wire(psbuf->st_ex_mode & ~S_IFMT));
 
+       buf += 12;
+       buflen -= 12;
+
        /* Now add in the owner and group sids. */
-       sid_linearize(ret_blob.data + 12,
-                     b_size - 12,
-                     &sid_owner);
-       sid_linearize(ret_blob.data + 12 + owner_sid_size,
-                     b_size - owner_sid_size - 12,
-                     &sid_group);
-       return ret_blob;
+       sid_linearize(buf, buflen, owner);
+       buf += owner_sid_size;
+       buflen -= owner_sid_size;
+
+       sid_linearize(buf, buflen, group);
+
+       return b_size;
 }
 
 /*
@@ -93,24 +92,28 @@ DATA_BLOB store_smb2_posix_info(TALLOC_CTX *mem_ctx,
 {
        uint64_t file_id = SMB_VFS_FS_FILE_ID(conn, psbuf);
        DATA_BLOB ret_blob = data_blob_null;
-       DATA_BLOB cc = smb2_posix_cc_info(mem_ctx,
-                                       conn,
-                                       reparse_tag,
-                                       psbuf);
-       if (cc.data == NULL) {
+       struct dom_sid owner = { .sid_rev_num = 0, };
+       struct dom_sid group = { .sid_rev_num = 0, };
+       ssize_t cc_len;
+
+       uid_to_sid(&owner, psbuf->st_ex_uid);
+       gid_to_sid(&group, psbuf->st_ex_gid);
+
+       cc_len = smb2_posix_cc_info(
+               conn, reparse_tag, psbuf, &owner, &group, NULL, 0);
+
+       if (cc_len == -1) {
                return data_blob_null;
        }
 
-       if (cc.length + 68 < 68) {
-               data_blob_free(&cc);
+       if (cc_len + 68 < 68) {
                return data_blob_null;
        }
 
        ret_blob = data_blob_talloc(mem_ctx,
                                NULL,
-                               cc.length + 68);
+                               cc_len + 68);
        if (ret_blob.data == NULL) {
-               data_blob_free(&cc);
                return data_blob_null;
        }
 
@@ -164,7 +167,14 @@ DATA_BLOB store_smb2_posix_info(TALLOC_CTX *mem_ctx,
        /*
         * Append a POSIX create context (variable bytes).
         */
-       memcpy(ret_blob.data + 68, cc.data, cc.length);
-       data_blob_free(&cc);
+       smb2_posix_cc_info(
+               conn,
+               reparse_tag,
+               psbuf,
+               &owner,
+               &group,
+               ret_blob.data + 68,
+               cc_len);
+
        return ret_blob;
 }