cryptodisk: Refactor password input out of crypto dev modules into cryptodisk

The crypto device modules should only be setting up the crypto devices and
not getting user input. This has the added benefit of simplifying the code
such that three essentially duplicate pieces of code are merged into one.

Add documentation of passphrase option for cryptomount as it is now usable.

Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

diff --git a/docs/grub.texi b/docs/grub.texi
index 99d0a01494d57cb3cd12a65c345b44cda22e8b25..a72d73ce3c08ffca0c4972b879eb66e4071cf86a 100644 (file)
--- a/docs/grub.texi
+++ b/docs/grub.texi
@@ -4307,9 +4307,11 @@ Alias for @code{hashsum --hash crc32 arg @dots{}}. See command @command{hashsum}
 @node cryptomount
 @subsection cryptomount
 
-@deffn Command cryptomount device|@option{-u} uuid|@option{-a}|@option{-b}
-Setup access to encrypted device. If necessary, passphrase
-is requested interactively. Option @var{device} configures specific grub device
+@deffn Command cryptomount [@option{-p} password] device|@option{-u} uuid|@option{-a}|@option{-b}
+Setup access to encrypted device. If @option{-p} is not given, a passphrase
+is requested interactively. Otherwise, the given @var{password} will be used and
+no passphrase will be requested interactively.
+Option @var{device} configures specific grub device
 (@pxref{Naming convention}); option @option{-u} @var{uuid} configures device
 with specified @var{uuid}; option @option{-a} configures all detected encrypted
 devices; option @option{-b} configures all geli containers that have boot flag set.

diff --git a/grub-core/disk/cryptodisk.c b/grub-core/disk/cryptodisk.c
index 14c661a86ea64868bc3f0f400a7ffc89cf2245ea..d12368a1f779b9783588aa7c724de571e9565aa8 100644 (file)
--- a/grub-core/disk/cryptodisk.c
+++ b/grub-core/disk/cryptodisk.c
@@ -1001,9 +1001,11 @@ grub_cryptodisk_scan_device_real (const char *name,
                                  grub_disk_t source,
                                  grub_cryptomount_args_t cargs)
 {
-  grub_err_t err;
+  grub_err_t ret = GRUB_ERR_NONE;
   grub_cryptodisk_t dev;
   grub_cryptodisk_dev_t cr;
+  int askpass = 0;
+  char *part = NULL;
 
   dev = grub_cryptodisk_get_by_source_disk (source);
 
@@ -1017,21 +1019,53 @@ grub_cryptodisk_scan_device_real (const char *name,
       return NULL;
     if (!dev)
       continue;
-    
-    err = cr->recover_key (source, dev, cargs);
-    if (err)
-    {
-      cryptodisk_close (dev);
-      return NULL;
-    }
+
+    if (!cargs->key_len)
+      {
+       /* Get the passphrase from the user, if no key data. */
+       askpass = 1;
+       if (source->partition != NULL)
+         part = grub_partition_get_name (source->partition);
+       grub_printf_ (N_("Enter passphrase for %s%s%s (%s): "), source->name,
+                    source->partition != NULL ? "," : "",
+                    part != NULL ? part : "",
+                    dev->uuid);
+       grub_free (part);
+
+       cargs->key_data = grub_malloc (GRUB_CRYPTODISK_MAX_PASSPHRASE);
+       if (cargs->key_data == NULL)
+         return NULL;
+
+       if (!grub_password_get ((char *) cargs->key_data, GRUB_CRYPTODISK_MAX_PASSPHRASE))
+         {
+           grub_error (GRUB_ERR_BAD_ARGUMENT, "passphrase not supplied");
+           goto error;
+         }
+       cargs->key_len = grub_strlen ((char *) cargs->key_data);
+      }
+
+    ret = cr->recover_key (source, dev, cargs);
+    if (ret != GRUB_ERR_NONE)
+      goto error;
 
     grub_cryptodisk_insert (dev, name, source);
 
-    return dev;
+    goto cleanup;
   }
-
   grub_error (GRUB_ERR_BAD_MODULE, "no cryptodisk module can handle this device");
-  return NULL;
+  goto cleanup;
+
+ error:
+  cryptodisk_close (dev);
+  dev = NULL;
+
+ cleanup:
+  if (askpass)
+    {
+      cargs->key_len = 0;
+      grub_free (cargs->key_data);
+    }
+  return dev;
 }
 
 #ifdef GRUB_UTIL

diff --git a/grub-core/disk/geli.c b/grub-core/disk/geli.c
index 777da3a0553cc96c2527eda05a53e470a7a7267d..7299a47d19a21c3d1d93299a02c1ef2fbfb23bed 100644 (file)
--- a/grub-core/disk/geli.c
+++ b/grub-core/disk/geli.c
@@ -135,8 +135,6 @@ const char *algorithms[] = {
   [0x16] = "aes"
 };
 
-#define MAX_PASSPHRASE 256
-
 static gcry_err_code_t
 geli_rekey (struct grub_cryptodisk *dev, grub_uint64_t zoneno)
 {
@@ -406,17 +404,14 @@ recover_key (grub_disk_t source, grub_cryptodisk_t dev, grub_cryptomount_args_t
   grub_uint8_t verify_key[GRUB_CRYPTO_MAX_MDLEN];
   grub_uint8_t zero[GRUB_CRYPTO_MAX_CIPHER_BLOCKSIZE];
   grub_uint8_t geli_cipher_key[64];
-  char passphrase[MAX_PASSPHRASE] = "";
   unsigned i;
   gcry_err_code_t gcry_err;
   struct grub_geli_phdr header;
-  char *tmp;
   grub_disk_addr_t sector;
   grub_err_t err;
 
-  /* Keyfiles are not implemented yet */
-  if (cargs->key_data != NULL || cargs->key_len)
-     return GRUB_ERR_NOT_IMPLEMENTED_YET;
+  if (cargs->key_data == NULL || cargs->key_len == 0)
+    return grub_error (GRUB_ERR_BAD_ARGUMENT, "no key data");
 
   if (dev->cipher->cipher->blocksize > GRUB_CRYPTO_MAX_CIPHER_BLOCKSIZE)
     return grub_error (GRUB_ERR_BUG, "cipher block is too long");
@@ -438,23 +433,12 @@ recover_key (grub_disk_t source, grub_cryptodisk_t dev, grub_cryptomount_args_t
 
   grub_puts_ (N_("Attempting to decrypt master key..."));
 
-  /* Get the passphrase from the user.  */
-  tmp = NULL;
-  if (source->partition)
-    tmp = grub_partition_get_name (source->partition);
-  grub_printf_ (N_("Enter passphrase for %s%s%s (%s): "), source->name,
-               source->partition ? "," : "", tmp ? : "",
-               dev->uuid);
-  grub_free (tmp);
-  if (!grub_password_get (passphrase, MAX_PASSPHRASE))
-    return grub_error (GRUB_ERR_BAD_ARGUMENT, "Passphrase not supplied");
-
   /* Calculate the PBKDF2 of the user supplied passphrase.  */
   if (grub_le_to_cpu32 (header.niter) != 0)
     {
       grub_uint8_t pbkdf_key[64];
-      gcry_err = grub_crypto_pbkdf2 (dev->hash, (grub_uint8_t *) passphrase,
-                                    grub_strlen (passphrase),
+      gcry_err = grub_crypto_pbkdf2 (dev->hash, cargs->key_data,
+                                    cargs->key_len,
                                     header.salt,
                                     sizeof (header.salt),
                                     grub_le_to_cpu32 (header.niter),
@@ -477,7 +461,7 @@ recover_key (grub_disk_t source, grub_cryptodisk_t dev, grub_cryptomount_args_t
        return grub_crypto_gcry_error (GPG_ERR_OUT_OF_MEMORY);
 
       grub_crypto_hmac_write (hnd, header.salt, sizeof (header.salt));
-      grub_crypto_hmac_write (hnd, passphrase, grub_strlen (passphrase));
+      grub_crypto_hmac_write (hnd, cargs->key_data, cargs->key_len);
 
       gcry_err = grub_crypto_hmac_fini (hnd, geomkey);
       if (gcry_err)

diff --git a/grub-core/disk/luks.c b/grub-core/disk/luks.c
index c5858fcf8a6b095849808154ff8f30f3b082ef67..39a7af6a436cbab2c2fe789494c677e32ba5be23 100644 (file)
--- a/grub-core/disk/luks.c
+++ b/grub-core/disk/luks.c
@@ -29,8 +29,6 @@
 
 GRUB_MOD_LICENSE ("GPLv3+");
 
-#define MAX_PASSPHRASE 256
-
 #define LUKS_KEY_ENABLED  0x00AC71F3
 
 /* On disk LUKS header */
@@ -158,17 +156,14 @@ luks_recover_key (grub_disk_t source,
   struct grub_luks_phdr header;
   grub_size_t keysize;
   grub_uint8_t *split_key = NULL;
-  char passphrase[MAX_PASSPHRASE] = "";
   grub_uint8_t candidate_digest[sizeof (header.mkDigest)];
   unsigned i;
   grub_size_t length;
   grub_err_t err;
   grub_size_t max_stripes = 1;
-  char *tmp;
 
-  /* Keyfiles are not implemented yet */
-  if (cargs->key_data != NULL || cargs->key_len)
-     return GRUB_ERR_NOT_IMPLEMENTED_YET;
+  if (cargs->key_data == NULL || cargs->key_len == 0)
+    return grub_error (GRUB_ERR_BAD_ARGUMENT, "no key data");
 
   err = grub_disk_read (source, 0, 0, sizeof (header), &header);
   if (err)
@@ -188,20 +183,6 @@ luks_recover_key (grub_disk_t source,
   if (!split_key)
     return grub_errno;
 
-  /* Get the passphrase from the user.  */
-  tmp = NULL;
-  if (source->partition)
-    tmp = grub_partition_get_name (source->partition);
-  grub_printf_ (N_("Enter passphrase for %s%s%s (%s): "), source->name,
-              source->partition ? "," : "", tmp ? : "",
-              dev->uuid);
-  grub_free (tmp);
-  if (!grub_password_get (passphrase, MAX_PASSPHRASE))
-    {
-      grub_free (split_key);
-      return grub_error (GRUB_ERR_BAD_ARGUMENT, "Passphrase not supplied");
-    }
-
   /* Try to recover master key from each active keyslot.  */
   for (i = 0; i < ARRAY_SIZE (header.keyblock); i++)
     {
@@ -216,8 +197,8 @@ luks_recover_key (grub_disk_t source,
       grub_dprintf ("luks", "Trying keyslot %d\n", i);
 
       /* Calculate the PBKDF2 of the user supplied passphrase.  */
-      gcry_err = grub_crypto_pbkdf2 (dev->hash, (grub_uint8_t *) passphrase,
-                                    grub_strlen (passphrase),
+      gcry_err = grub_crypto_pbkdf2 (dev->hash, cargs->key_data,
+                                    cargs->key_len,
                                     header.keyblock[i].passwordSalt,
                                     sizeof (header.keyblock[i].passwordSalt),
                                     grub_be_to_cpu32 (header.keyblock[i].

diff --git a/grub-core/disk/luks2.c b/grub-core/disk/luks2.c
index 2cbec8acc28d93dfcb72ff918a47e853b483219f..09740b53f993090d0ba119f86f168fa809da5694 100644 (file)
--- a/grub-core/disk/luks2.c
+++ b/grub-core/disk/luks2.c
@@ -35,8 +35,6 @@ GRUB_MOD_LICENSE ("GPLv3+");
 #define LUKS_MAGIC_1ST "LUKS\xBA\xBE"
 #define LUKS_MAGIC_2ND "SKUL\xBA\xBE"
 
-#define MAX_PASSPHRASE 256
-
 enum grub_luks2_kdf_type
 {
   LUKS2_KDF_TYPE_ARGON2I,
@@ -549,8 +547,7 @@ luks2_recover_key (grub_disk_t source,
                   grub_cryptomount_args_t cargs)
 {
   grub_uint8_t candidate_key[GRUB_CRYPTODISK_MAX_KEYLEN];
-  char passphrase[MAX_PASSPHRASE], cipher[32];
-  char *json_header = NULL, *part = NULL, *ptr;
+  char cipher[32], *json_header = NULL, *ptr;
   grub_size_t candidate_key_len = 0, json_idx, size;
   grub_luks2_header_t header;
   grub_luks2_keyslot_t keyslot;
@@ -560,9 +557,8 @@ luks2_recover_key (grub_disk_t source,
   grub_json_t *json = NULL, keyslots;
   grub_err_t ret;
 
-  /* Keyfiles are not implemented yet */
-  if (cargs->key_data != NULL || cargs->key_len)
-     return GRUB_ERR_NOT_IMPLEMENTED_YET;
+  if (cargs->key_data == NULL || cargs->key_len == 0)
+    return grub_error (GRUB_ERR_BAD_ARGUMENT, "no key data");
 
   ret = luks2_read_header (source, &header);
   if (ret)
@@ -589,18 +585,6 @@ luks2_recover_key (grub_disk_t source,
       goto err;
     }
 
-  /* Get the passphrase from the user. */
-  if (source->partition)
-    part = grub_partition_get_name (source->partition);
-  grub_printf_ (N_("Enter passphrase for %s%s%s (%s): "), source->name,
-               source->partition ? "," : "", part ? : "",
-               crypt->uuid);
-  if (!grub_password_get (passphrase, MAX_PASSPHRASE))
-    {
-      ret = grub_error (GRUB_ERR_BAD_ARGUMENT, "Passphrase not supplied");
-      goto err;
-    }
-
   if (grub_json_getvalue (&keyslots, json, "keyslots") ||
       grub_json_getsize (&size, &keyslots))
     {
@@ -725,7 +709,7 @@ luks2_recover_key (grub_disk_t source,
        }
 
       ret = luks2_decrypt_key (candidate_key, source, crypt, &keyslot,
-                              (const grub_uint8_t *) passphrase, grub_strlen (passphrase));
+                              cargs->key_data, cargs->key_len);
       if (ret)
        {
          grub_dprintf ("luks2", "Decryption with keyslot \"%" PRIuGRUB_UINT64_T "\" failed: %s\n",
@@ -777,7 +761,6 @@ luks2_recover_key (grub_disk_t source,
     }
 
  err:
-  grub_free (part);
   grub_free (json_header);
   grub_json_free (json);
   return ret;

diff --git a/include/grub/cryptodisk.h b/include/grub/cryptodisk.h
index 282f8ac4567d503c0ab3e58dc9bcb089027b53be..5bd970692f7b354cb5eca5b2f338b52cf2a85c32 100644 (file)
--- a/include/grub/cryptodisk.h
+++ b/include/grub/cryptodisk.h
@@ -59,6 +59,7 @@ typedef enum
 #define GRUB_CRYPTODISK_GF_LOG_BYTES (GRUB_CRYPTODISK_GF_LOG_SIZE - 3)
 #define GRUB_CRYPTODISK_GF_BYTES (1U << GRUB_CRYPTODISK_GF_LOG_BYTES)
 #define GRUB_CRYPTODISK_MAX_KEYLEN 128
+#define GRUB_CRYPTODISK_MAX_PASSPHRASE 256
 
 struct grub_cryptodisk;