vfs_fruit: let fruit_open_meta() with O_CREAT return a fake-fd

This is the final step in implementing the needed macOS semantics on the
FinderInfo stream: as long as the client hasn't written a non-zero
FinderInfo blob to the stream, there mustn't be a visible filesystem
entry for other openers.

Bug: https://bugzilla.samba.org/show_bug.cgi?id=13646

Signed-off-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Thu Nov  1 01:14:23 CET 2018 on sn-devel-144

diff --git a/selftest/knownfail.d/samba3.vfs.fruit b/selftest/knownfail.d/samba3.vfs.fruit
index 2d3c21caf918fc2e37f2010257c695b97885ff30..6307e2b34043b5f960a67ad7861eeb004b5bed3e 100644 (file)
--- a/selftest/knownfail.d/samba3.vfs.fruit
+++ b/selftest/knownfail.d/samba3.vfs.fruit
@@ -1,5 +1,2 @@
 ^samba3.vfs.fruit streams_depot.OS X AppleDouble file conversion\(nt4_dc\)
 ^samba3.vfs.fruit streams_depot.OS X AppleDouble file conversion without embedded xattr\(nt4_dc\)
-^samba3.vfs.fruit metadata_netatalk.empty_stream\(nt4_dc\)
-^samba3.vfs.fruit metadata_stream.empty_stream\(nt4_dc\)
-^samba3.vfs.fruit streams_depot.empty_stream\(nt4_dc\)

diff --git a/source3/modules/vfs_fruit.c b/source3/modules/vfs_fruit.c
index 360070db8c2bb7aebcc42cf9e16869980de573df..efe88efcaeb307ce3c18d33a837df92cc492d44c 100644 (file)
--- a/source3/modules/vfs_fruit.c
+++ b/source3/modules/vfs_fruit.c
@@ -3403,66 +3403,68 @@ static int fruit_connect(vfs_handle_struct *handle,
        return rc;
 }
 
+static int fruit_fake_fd(void)
+{
+       int pipe_fds[2];
+       int fd;
+       int ret;
+
+       /*
+        * Return a valid fd, but ensure any attempt to use it returns
+        * an error (EPIPE). Once we get a write on the handle, we open
+        * the real fd.
+        */
+       ret = pipe(pipe_fds);
+       if (ret != 0) {
+               return -1;
+       }
+       fd = pipe_fds[0];
+       close(pipe_fds[1]);
+
+       return fd;
+}
+
 static int fruit_open_meta_stream(vfs_handle_struct *handle,
                                  struct smb_filename *smb_fname,
                                  files_struct *fsp,
                                  int flags,
                                  mode_t mode)
 {
-       AfpInfo *ai = NULL;
-       char afpinfo_buf[AFP_INFO_SIZE];
-       ssize_t len, written;
-       int hostfd = -1;
-       int rc = -1;
+       struct fruit_config_data *config = NULL;
+       struct fio *fio = NULL;
+       int open_flags = flags & ~O_CREAT;
+       int fd;
 
-       hostfd = SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, flags, mode);
-       if (hostfd == -1) {
-               return -1;
-       }
+       DBG_DEBUG("Path [%s]\n", smb_fname_str_dbg(smb_fname));
 
-       if (!(flags & (O_CREAT | O_TRUNC))) {
-               return hostfd;
-       }
+       SMB_VFS_HANDLE_GET_DATA(handle, config,
+                               struct fruit_config_data, return -1);
 
-       ai = afpinfo_new(talloc_tos());
-       if (ai == NULL) {
-               rc = -1;
-               goto fail;
-       }
+       fio = VFS_ADD_FSP_EXTENSION(handle, fsp, struct fio, NULL);
+       fio->type = ADOUBLE_META;
+       fio->config = config;
 
-       len = afpinfo_pack(ai, afpinfo_buf);
-       if (len != AFP_INFO_SIZE) {
-               rc = -1;
-               goto fail;
+       fd = SMB_VFS_NEXT_OPEN(handle, smb_fname, fsp, open_flags, mode);
+       if (fd != -1) {
+               return fd;
        }
 
-       /* Set fd, needed in SMB_VFS_NEXT_PWRITE() */
-       fsp->fh->fd = hostfd;
-
-       written = SMB_VFS_NEXT_PWRITE(handle, fsp, afpinfo_buf,
-                                     AFP_INFO_SIZE, 0);
-       fsp->fh->fd = -1;
-       if (written != AFP_INFO_SIZE) {
-               DBG_ERR("bad write [%zd/%d]\n", written, AFP_INFO_SIZE);
-               rc = -1;
-               goto fail;
+       if (!(flags & O_CREAT)) {
+               VFS_REMOVE_FSP_EXTENSION(handle, fsp);
+               return -1;
        }
 
-       rc = 0;
+       fd = fruit_fake_fd();
+       if (fd == -1) {
+               VFS_REMOVE_FSP_EXTENSION(handle, fsp);
+               return -1;
+       }
 
-fail:
-       DBG_DEBUG("rc=%d, fd=%d\n", rc, hostfd);
+       fio->fake_fd = true;
+       fio->flags = flags;
+       fio->mode = mode;
 
-       if (rc != 0) {
-               int saved_errno = errno;
-               if (hostfd >= 0) {
-                       fsp->fh->fd = hostfd;
-                       SMB_VFS_NEXT_CLOSE(handle, fsp);
-               }
-               hostfd = -1;
-               errno = saved_errno;
-       }
-       return hostfd;
+       return fd;
 }
 
 static int fruit_open_meta_netatalk(vfs_handle_struct *handle,
@@ -3471,56 +3473,42 @@ static int fruit_open_meta_netatalk(vfs_handle_struct *handle,
                                    int flags,
                                    mode_t mode)
 {
-       int rc;
-       int fakefd = -1;
+       struct fruit_config_data *config = NULL;
+       struct fio *fio = NULL;
        struct adouble *ad = NULL;
-       int fds[2];
+       bool meta_exists = false;
+       int fd;
 
        DBG_DEBUG("Path [%s]\n", smb_fname_str_dbg(smb_fname));
 
-       /*
-        * Return a valid fd, but ensure any attempt to use it returns an error
-        * (EPIPE). All operations on the smb_fname or the fsp will use path
-        * based syscalls.
-        */
-       rc = pipe(fds);
-       if (rc != 0) {
-               goto exit;
+       ad = ad_get(talloc_tos(), handle, smb_fname, ADOUBLE_META);
+       if (ad != NULL) {
+               meta_exists = true;
        }
-       fakefd = fds[0];
-       close(fds[1]);
-
-       if (flags & (O_CREAT | O_TRUNC)) {
-               /*
-                * The attribute does not exist or needs to be truncated,
-                * create an AppleDouble EA
-                */
-               ad = ad_init(fsp, handle, ADOUBLE_META);
-               if (ad == NULL) {
-                       rc = -1;
-                       goto exit;
-               }
 
-               rc = ad_set(ad, fsp->fsp_name);
-               if (rc != 0) {
-                       rc = -1;
-                       goto exit;
-               }
+       TALLOC_FREE(ad);
 
-               TALLOC_FREE(ad);
+       if (!meta_exists && !(flags & O_CREAT)) {
+               errno = ENOENT;
+               return -1;
        }
 
-exit:
-       DEBUG(10, ("fruit_open meta rc=%d, fd=%d\n", rc, fakefd));
-       if (rc != 0) {
-               int saved_errno = errno;
-               if (fakefd >= 0) {
-                       close(fakefd);
-               }
-               fakefd = -1;
-               errno = saved_errno;
+       fd = fruit_fake_fd();
+       if (fd == -1) {
+               return -1;
        }
-       return fakefd;
+
+       SMB_VFS_HANDLE_GET_DATA(handle, config,
+                               struct fruit_config_data, return -1);
+
+       fio = VFS_ADD_FSP_EXTENSION(handle, fsp, struct fio, NULL);
+       fio->type = ADOUBLE_META;
+       fio->config = config;
+       fio->fake_fd = true;
+       fio->flags = flags;
+       fio->mode = mode;
+
+       return fd;
 }
 
 static int fruit_open_meta(vfs_handle_struct *handle,
@@ -3529,7 +3517,6 @@ static int fruit_open_meta(vfs_handle_struct *handle,
 {
        int fd;
        struct fruit_config_data *config = NULL;
-       struct fio *fio = NULL;
 
        DBG_DEBUG("path [%s]\n", smb_fname_str_dbg(smb_fname));
 
@@ -3554,14 +3541,6 @@ static int fruit_open_meta(vfs_handle_struct *handle,
 
        DBG_DEBUG("path [%s] fd [%d]\n", smb_fname_str_dbg(smb_fname), fd);
 
-       if (fd == -1) {
-               return -1;
-       }
-
-       fio = VFS_ADD_FSP_EXTENSION(handle, fsp, struct fio, NULL);
-       fio->type = ADOUBLE_META;
-       fio->config = config;
-
        return fd;
 }