mke2fs: add support for copying signature blobs in the fs-verity metadata

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/misc/create_inode.c b/misc/create_inode.c
index c11c00f2a0b038ff52892cb1338c1d5934f4047d..9204d87a488240975740776c76a8740edec9eb9e 100644 (file)
--- a/misc/create_inode.c
+++ b/misc/create_inode.c
@@ -620,6 +620,36 @@ static errcode_t copy_fs_verity_data(ext2_file_t e2_file, ext2_off_t e2_offset,
                                continue;
                        return errno;
                }
+               /*
+                * In order to support copying in signature blob, we
+                * need to set the descriptor's sig_size field (which
+                * is the __reserved_0x04 field in the userspace
+                * version of the structure if there is a signature
+                * blob.  To deal with this, we rely on the fact that
+                * size of the fsverity descriptor (256 bytes) is
+                * significantly smaller than COPY_FILE_BUFLEN (64k
+                * bytes), and that combined size descriptor and
+                * signature blob will fit in COPY_FILE_BUFLEN.
+                */
+               if (metadata_type == FS_VERITY_METADATA_TYPE_DESCRIPTOR) {
+                       int     sig_size;
+                       struct fsverity_descriptor *desc = (void *) buf;
+
+                       arg.metadata_type = FS_VERITY_METADATA_TYPE_SIGNATURE;
+                       arg.buf_ptr += size;
+                       arg.length -= size;
+                       arg.offset = 0;
+                       sig_size = ioctl(fd, FS_IOC_READ_VERITY_METADATA, &arg);
+                       if (sig_size > 0) {
+                               desc->__reserved_0x04 =
+                                       ext2fs_cpu_to_le32(sig_size);
+                               size += sig_size;
+                       }
+                       err = write_all(e2_file, e2_offset, buf, size);
+                       if (err == 0)
+                               *written += size;
+                       return err;
+               }
                err = write_all(e2_file, e2_offset, buf, size);
                if (err)
                        return err;
@@ -668,8 +698,8 @@ static errcode_t copy_fs_verity(ext2_filsys fs, int fd,
        offset = round_up(offset+written, fs->blocksize, 0);
 
        /*
-        * Write the verity descriptor (we don't handle signature blobs),
-        * starting at the next file system block boundary
+        * Write the verity descriptor, starting at the next file
+        * system block boundary
         */
        err = copy_fs_verity_data(e2_file, offset, fd,
                                  FS_VERITY_METADATA_TYPE_DESCRIPTOR,