[PATCH 7/7] Add support for using a whole device as a keyfile

[John Lane]

From: Paul Gideon Dann <address@hidden>

---
 grub-core/disk/cryptodisk.c | 86 +++++++++++++++++++++++++++++++++++----------
 1 file changed, 68 insertions(+), 18 deletions(-)

diff --git a/grub-core/disk/cryptodisk.c b/grub-core/disk/cryptodisk.c
index 6fc2c23aa..a8937e5e3 100644
--- a/grub-core/disk/cryptodisk.c
+++ b/grub-core/disk/cryptodisk.c
@@ -1032,26 +1032,76 @@ grub_cmd_cryptomount (grub_extcmd_context_t ctxt, int 
argc, char **args)
       else
         {
           keyfile_offset = state[5].set ? grub_strtoul (state[5].arg, 0, 0) : 
0;
-          keyfile_size = requested_keyfile_size ? requested_keyfile_size : \
-                                            GRUB_CRYPTODISK_MAX_KEYFILE_SIZE;
-
-          keyfile = grub_file_open (state[4].arg);
-          if (!keyfile)
-            grub_printf (N_("Unable to open key file %s\n"), state[4].arg);
-          else if (grub_file_seek (keyfile, keyfile_offset) == (grub_off_t)-1)
-            grub_printf (N_("Unable to seek to offset %d in key file\n"), 
keyfile_offset);
-          else
+
+          if (grub_strchr (state[4].arg, '/'))
             {
-              keyfile_size = grub_file_read (keyfile, keyfile_buffer, 
keyfile_size);
-              if (keyfile_size == (grub_size_t)-1)
-                 grub_printf (N_("Error reading key file\n"));
-             else if (requested_keyfile_size && (keyfile_size != 
requested_keyfile_size))
-                 grub_printf (N_("Cannot read %llu bytes for key file (read 
%llu bytes)\n"),
-                                                (unsigned long long) 
requested_keyfile_size,
-                                               (unsigned long long) 
keyfile_size);
+              keyfile_size = requested_keyfile_size ? requested_keyfile_size : 
\
+                                                 
GRUB_CRYPTODISK_MAX_KEYFILE_SIZE;
+              keyfile = grub_file_open (state[4].arg);
+              if (!keyfile)
+                grub_printf (N_("Unable to open key file %s\n"), state[4].arg);
+              else if (grub_file_seek (keyfile, keyfile_offset) == 
(grub_off_t)-1)
+                grub_printf (N_("Unable to seek to offset %d in key file\n"), 
keyfile_offset);
               else
-                key = keyfile_buffer;
-           }
+                {
+                  keyfile_size = grub_file_read (keyfile, keyfile_buffer, 
keyfile_size);
+                  if (keyfile_size == (grub_size_t)-1)
+                     grub_printf (N_("Error reading key file\n"));
+                  else if (requested_keyfile_size && (keyfile_size != 
requested_keyfile_size))
+                     grub_printf (N_("Cannot read %llu bytes for key file 
(read %llu bytes)\n"),
+                                                    (unsigned long long) 
requested_keyfile_size,
+                                                    (unsigned long long) 
keyfile_size);
+                  else
+                    key = keyfile_buffer;
+                }
+            }
+          else
+            {
+              grub_disk_t keydisk;
+              char* keydisk_name;
+              grub_err_t err;
+              grub_uint64_t total_sectors;
+
+              keydisk_name = grub_file_get_device_name(state[4].arg);
+              keydisk = grub_disk_open (keydisk_name);
+              if (!keydisk)
+                {
+                  grub_printf (N_("Unable to open disk %s\n"), keydisk_name);
+                  goto cleanup_keydisk_name;
+                }
+
+              total_sectors = grub_disk_get_size (keydisk);
+              if (total_sectors == GRUB_DISK_SIZE_UNKNOWN)
+                {
+                  grub_printf (N_("Unable to determine size of disk %s\n"), 
keydisk_name);
+                  goto cleanup_keydisk;
+                }
+
+              keyfile_size = (total_sectors << GRUB_DISK_SECTOR_BITS);
+              if (requested_keyfile_size > 0 && requested_keyfile_size < 
keyfile_size)
+                keyfile_size = requested_keyfile_size;
+              if (keyfile_size > GRUB_CRYPTODISK_MAX_KEYFILE_SIZE)
+                {
+                  grub_printf (N_("Key file size exceeds maximum (%llu)\n"), \
+                               (unsigned long long) 
GRUB_CRYPTODISK_MAX_KEYFILE_SIZE);
+                  goto cleanup_keydisk;
+                }
+
+              err = grub_disk_read (keydisk, 0, keyfile_offset, keyfile_size, 
keyfile_buffer);
+              if (err != GRUB_ERR_NONE)
+                {
+                  grub_printf (N_("Failed to read from disk %s\n"), 
keydisk_name);
+                  keyfile_size = 0;
+                  goto cleanup_keydisk;
+                }
+
+              key = keyfile_buffer;
+
+              cleanup_keydisk:
+              grub_disk_close (keydisk);
+              cleanup_keydisk_name:
+              grub_free (keydisk_name);
+            }
         }
     }
 
-- 
2.16.2