From ecef526a51c5a276681472fd6df239570c9ce518 Mon Sep 17 00:00:00 2001

From: Miloslav Trmač <mitr@redhat.com>

Date: Nov 07 2017 15:55:55 +0000

Subject: Stop using crypt_get_error

Instead of crypt_get_error, which has been removed in cryptsetup 2.0,

set up a log callback, which is available in both older and newer

versions.

Fixes #13.

---

diff --git a/lib/volume_luks.c b/lib/volume_luks.c

index 14794d7..f4bf2c8 100644

--- a/lib/volume_luks.c

+++ b/lib/volume_luks.c

@@ -61,17 +61,13 @@ my_strerror (int err_no)

 }

 /* Set ERROR based on libcryptsetup error state after returning RES.

-   Use CODE. */

+   Use CODE and LAST_LOG_ENTRY. */

 static void

-error_from_cryptsetup (GError **error, LIBVKError code, int res)

+error_from_cryptsetup (GError **error, LIBVKError code, int res,

+		       char *last_log_entry)

 {

-  /* It's not possible to get the error message length from libcryptsetup, just

-     guess. */

-  char crypt_msg[4096];

-

-  crypt_get_error (crypt_msg, sizeof (crypt_msg));

-  if (crypt_msg[0] != '\0')

-    g_set_error (error, LIBVK_ERROR, code, "%s", crypt_msg);

+  if (last_log_entry != NULL && last_log_entry[0] != '\0')

+    g_set_error (error, LIBVK_ERROR, code, "%s", last_log_entry);

   else

     {

       char *s;

@@ -82,17 +78,33 @@ error_from_cryptsetup (GError **error, LIBVKError code, int res)

     }

 }

+static void

+record_cryptsetup_log_entry (int level, const char *msg, void *usrptr)

+{

+  char **last_log_entry = usrptr;

+

+  if (level == CRYPT_LOG_ERROR)

+    {

+      g_free (*last_log_entry);

+      *last_log_entry = g_strdup (msg);

+    }

+}

+

 /* Open volume PATH and load its header.

+   Set up *LAST_LOG_ENTRY to be updated to the last logged message for the

+   device.  The caller must g_free(*LAST_LOG_ENTRY) after closing the device.

    Return the volume, or NULL on error. */

 static struct crypt_device *

-open_crypt_device (const char *path, GError **error)

+open_crypt_device (const char *path, char **last_log_entry, GError **error)

 {

   struct crypt_device *cd;

   int r;

+  *last_log_entry = NULL;

   r = crypt_init (&cd, path);

   if (r < 0)

     goto err;

+  crypt_set_log_callback(cd, record_cryptsetup_log_entry, last_log_entry);

   r = crypt_load (cd, CRYPT_LUKS1, NULL);

   if (r < 0)

     goto err_cd;

@@ -101,9 +113,12 @@ open_crypt_device (const char *path, GError **error)

  err_cd:

   crypt_free (cd);

  err:

-  error_from_cryptsetup (error, LIBVK_ERROR_VOLUME_UNKNOWN_FORMAT, r);

+  error_from_cryptsetup (error, LIBVK_ERROR_VOLUME_UNKNOWN_FORMAT, r,

+			 *last_log_entry);

   g_prefix_error (error, _("Error getting information about volume `%s': "),

 		  path);

+  g_free (*last_log_entry);

+  *last_log_entry = NULL;

   return NULL;

 }

@@ -173,10 +188,11 @@ luks_volume_open (struct libvk_volume *vol, const char *path, GError **error)

 {

   struct luks_volume *luks;

   struct crypt_device *cd;

+  char *last_log_entry;

   const char *uuid;

   (void)vol;

-  cd = open_crypt_device (path, error);

+  cd = open_crypt_device (path, &last_log_entry, error);

   if (cd == NULL)

     return NULL;

   /* A bit of paranoia */

@@ -187,6 +203,7 @@ luks_volume_open (struct libvk_volume *vol, const char *path, GError **error)

 		   _("UUID mismatch between libblkid and libcryptsetup: `%s' "

 		     "vs. `%s'"), vol->uuid, uuid);

       crypt_free (cd);

+      g_free (last_log_entry);

       return NULL;

     }

@@ -195,6 +212,7 @@ luks_volume_open (struct libvk_volume *vol, const char *path, GError **error)

   luks->cipher_mode = g_strdup (crypt_get_cipher_mode (cd));

   luks->key_bytes = crypt_get_volume_key_size (cd);

   crypt_free (cd);

+  g_free (last_log_entry);

   luks->key = NULL;

   luks->passphrase = NULL;

@@ -256,7 +274,7 @@ luks_get_secret (struct libvk_volume *vol, enum libvk_secret secret_type,

 		 const struct libvk_ui *ui, GError **error)

 {

   struct crypt_device *cd;

-  char *passphrase;

+  char *last_log_entry, *passphrase;

   void *key;

   size_t key_length;

   int slot;

@@ -276,7 +294,7 @@ luks_get_secret (struct libvk_volume *vol, enum libvk_secret secret_type,

 		   _("Encryption information type unsupported in LUKS"));

       goto err;

     }

-  cd = open_crypt_device (vol->path, error);

+  cd = open_crypt_device (vol->path, &last_log_entry, error);

   if (cd == NULL)

     goto err;

   key_length = crypt_get_volume_key_size (cd);

@@ -303,7 +321,7 @@ luks_get_secret (struct libvk_volume *vol, enum libvk_secret secret_type,

       g_free_passphrase (passphrase);

       if (r != -EPERM)

 	{

-	  error_from_cryptsetup (error, LIBVK_ERROR_FAILED, r);

+	  error_from_cryptsetup (error, LIBVK_ERROR_FAILED, r, last_log_entry);

 	  g_prefix_error (error, _("Error getting LUKS data encryption key: "));

 	  goto err_prompt;

 	}

@@ -322,12 +340,14 @@ luks_get_secret (struct libvk_volume *vol, enum libvk_secret secret_type,

   vol->v.luks->passphrase_slot = slot;

   g_free (prompt);

   crypt_free (cd);

+  g_free (last_log_entry);

   return 0;

  err_prompt:

   g_free (prompt);

   g_free_key (key, key_length);

   crypt_free (cd);

+  g_free (last_log_entry);

  err:

   return -1;

 }

@@ -383,11 +403,12 @@ luks_load_packet (struct libvk_volume *vol, const struct libvk_volume *packet,

   if (packet->v.luks->key != NULL)

     {

       struct crypt_device *cd;

+      char *last_log_entry;

       int r;

       g_return_val_if_fail (vol->v.luks->key_bytes == packet->v.luks->key_bytes,

 			    -1);

-      cd = open_crypt_device (vol->path, error);

+      cd = open_crypt_device (vol->path, &last_log_entry, error);

       if (cd == NULL)

 	return -1;

       r = crypt_volume_key_verify (cd, packet->v.luks->key,

@@ -395,21 +416,25 @@ luks_load_packet (struct libvk_volume *vol, const struct libvk_volume *packet,

       crypt_free (cd);

       if (r < 0)

 	{

-	  error_from_cryptsetup (error, LIBVK_ERROR_PACKET_VOLUME_MISMATCH, r);

+	  error_from_cryptsetup (error, LIBVK_ERROR_PACKET_VOLUME_MISMATCH, r,

+				 last_log_entry);

 	  g_prefix_error (error, _("LUKS data encryption key in packet is "

 				   "invalid: "));

+	  g_free (last_log_entry);

 	  return -1;

 	}

+      g_free (last_log_entry);

       luks_replace_key (vol, packet->v.luks->key);

     }

   if (packet->v.luks->passphrase != NULL)

     {

       struct crypt_device *cd;

+      char *last_log_entry;

       void *key;

       size_t key_size;

       int r;

-      cd = open_crypt_device (vol->path, error);

+      cd = open_crypt_device (vol->path, &last_log_entry, error);

       if (cd == NULL)

 	return -1;

       key_size = crypt_get_volume_key_size (cd);

@@ -420,10 +445,13 @@ luks_load_packet (struct libvk_volume *vol, const struct libvk_volume *packet,

       crypt_free (cd);

       if (r < 0)

 	{

-	  error_from_cryptsetup (error, LIBVK_ERROR_PACKET_VOLUME_MISMATCH, r);

+	  error_from_cryptsetup (error, LIBVK_ERROR_PACKET_VOLUME_MISMATCH, r,

+				 last_log_entry);

 	  g_prefix_error (error, _("LUKS passphrase in packet is invalid: "));

+	  g_free (last_log_entry);

 	  return -1;

 	}

+      g_free (last_log_entry);

       luks_replace_passphrase (vol, packet->v.luks->passphrase);

       vol->v.luks->passphrase_slot = r;

       if (packet->v.luks->key == NULL)

@@ -446,7 +474,7 @@ luks_apply_secret (struct libvk_volume *vol, const struct libvk_volume *packet,

 		   GError **error)

 {

   struct crypt_device *cd;

-  char *prompt, *prompt2, *error_prompt, *passphrase;

+  char *last_log_entry, *prompt, *prompt2, *error_prompt, *passphrase;

   unsigned failed;

   int res;

@@ -498,7 +526,7 @@ luks_apply_secret (struct libvk_volume *vol, const struct libvk_volume *packet,

   goto err_prompts;

  got_passphrase:

-  cd = open_crypt_device (vol->path, error);

+  cd = open_crypt_device (vol->path, &last_log_entry, error);

   if (cd == NULL)

     goto err_passphrase;

   res = crypt_keyslot_add_by_volume_key (cd, CRYPT_ANY_SLOT,

@@ -508,10 +536,12 @@ luks_apply_secret (struct libvk_volume *vol, const struct libvk_volume *packet,

   crypt_free (cd);

   if (res < 0)

     {

-      error_from_cryptsetup (error, LIBVK_ERROR_FAILED, res);

+      error_from_cryptsetup (error, LIBVK_ERROR_FAILED, res, last_log_entry);

       g_prefix_error (error, _("Error adding a LUKS passphrase"));

+      g_free (last_log_entry);

       goto err_passphrase;

     }

+  g_free (last_log_entry);

   g_return_val_if_fail (vol->v.luks->key_bytes == packet->v.luks->key_bytes,

 			-1);

@@ -542,6 +572,7 @@ luks_add_secret (struct libvk_volume *vol, enum libvk_secret secret_type,

 		 const void *secret, size_t size, GError **error)

 {

   struct crypt_device *cd;

+  char *last_log_entry;

   int res;

   if (secret_type != LIBVK_SECRET_PASSPHRASE)

@@ -562,7 +593,7 @@ luks_add_secret (struct libvk_volume *vol, enum libvk_secret secret_type,

 		   _("The passphrase must be a string"));

       return -1;

     }

-  cd = open_crypt_device (vol->path, error);

+  cd = open_crypt_device (vol->path, &last_log_entry, error);

   if (cd == NULL)

     return -1;

   res = crypt_keyslot_add_by_volume_key (cd, CRYPT_ANY_SLOT, vol->v.luks->key,

@@ -570,10 +601,12 @@ luks_add_secret (struct libvk_volume *vol, enum libvk_secret secret_type,

   crypt_free (cd);

   if (res < 0)

     {

-      error_from_cryptsetup (error, LIBVK_ERROR_FAILED, res);

+      error_from_cryptsetup (error, LIBVK_ERROR_FAILED, res, last_log_entry);

       g_prefix_error (error, _("Error adding a LUKS passphrase"));

+      g_free (last_log_entry);

       return -1;

     }

+  g_free (last_log_entry);

   luks_replace_passphrase (vol, secret);

   vol->v.luks->passphrase_slot = res;

@@ -823,12 +856,13 @@ luks_open_with_packet (struct libvk_volume *vol,

 		       GError **error)

 {

   struct crypt_device *cd;

+  char *last_log_entry;

   void *to_free;

   const void *key;

   int r;

   size_t key_size;

-  cd = open_crypt_device (vol->path, error);

+  cd = open_crypt_device (vol->path, &last_log_entry, error);

   if (cd == NULL)

     goto err;

   if (packet->v.luks->key != NULL)

@@ -846,7 +880,7 @@ luks_open_with_packet (struct libvk_volume *vol,

 				strlen (packet->v.luks->passphrase));

       if (r < 0)

 	{

-	  error_from_cryptsetup (error, LIBVK_ERROR_FAILED, r);

+	  error_from_cryptsetup (error, LIBVK_ERROR_FAILED, r, last_log_entry);

 	  g_prefix_error (error, _("Error getting LUKS data encryption key: "));

 	  goto err_to_free;

 	}

@@ -862,7 +896,7 @@ luks_open_with_packet (struct libvk_volume *vol,

   r = crypt_activate_by_volume_key (cd, name, key, key_size, 0);

   if (r < 0)

     {

-      error_from_cryptsetup (error, LIBVK_ERROR_FAILED, r);

+      error_from_cryptsetup (error, LIBVK_ERROR_FAILED, r, last_log_entry);

       g_prefix_error (error, _("Error opening LUKS volume: "));

       goto err_to_free;

     }

@@ -870,6 +904,7 @@ luks_open_with_packet (struct libvk_volume *vol,

   if (to_free != NULL)

     g_free_key (to_free, key_size);

   crypt_free (cd);

+  g_free (last_log_entry);

   return 0;

  err_to_free:

@@ -877,6 +912,7 @@ luks_open_with_packet (struct libvk_volume *vol,

     g_free_key (to_free, key_size);

  err_cd:

   crypt_free (cd);

+  g_free (last_log_entry);

  err:

   return -1;

 }