1 files changed, 109 insertions, 0 deletions
diff --git a/grub-core/lib/pbkdf2.c b/grub-core/lib/pbkdf2.c
new file mode 100644
index 0000000..28aa96c
--- /dev/null
+++ b/grub-core/lib/pbkdf2.c
@@ -0,0 +1,109 @@
+/* gc-pbkdf2-sha1.c --- Password-Based Key Derivation Function a'la PKCS#5
+   Copyright (C) 2002, 2003, 2004, 2005, 2006, 2009 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+/* Written by Simon Josefsson.  */
+/* Imported from gnulib.  */
+
+#include <grub/crypto.h>
+#include <grub/mm.h>
+#include <grub/misc.h>
+#include <grub/dl.h>
+
+GRUB_MOD_LICENSE ("GPLv2+");
+
+/* Implement PKCS#5 PBKDF2 as per RFC 2898.  The PRF to use is HMAC variant
+   of digest supplied by MD.  Inputs are the password P of length PLEN,
+   the salt S of length SLEN, the iteration counter C (> 0), and the
+   desired derived output length DKLEN.  Output buffer is DK which
+   must have room for at least DKLEN octets.  The output buffer will
+   be filled with the derived data.  */
+
+gcry_err_code_t
+grub_crypto_pbkdf2 (const struct gcry_md_spec *md,
+		    const grub_uint8_t *P, grub_size_t Plen,
+		    const grub_uint8_t *S, grub_size_t Slen,
+		    unsigned int c,
+		    grub_uint8_t *DK, grub_size_t dkLen)
+{
+  unsigned int hLen = md->mdlen;
+  grub_uint8_t U[GRUB_CRYPTO_MAX_MDLEN];
+  grub_uint8_t T[GRUB_CRYPTO_MAX_MDLEN];
+  unsigned int u;
+  unsigned int l;
+  unsigned int r;
+  unsigned int i;
+  unsigned int k;
+  gcry_err_code_t rc;
+  grub_uint8_t *tmp;
+  grub_size_t tmplen = Slen + 4;
+
+  if (md->mdlen > GRUB_CRYPTO_MAX_MDLEN || md->mdlen == 0)
+    return GPG_ERR_INV_ARG;
+
+  if (c == 0)
+    return GPG_ERR_INV_ARG;
+
+  if (dkLen == 0)
+    return GPG_ERR_INV_ARG;
+
+  if (dkLen > 4294967295U)
+    return GPG_ERR_INV_ARG;
+
+  l = ((dkLen - 1) / hLen) + 1;
+  r = dkLen - (l - 1) * hLen;
+
+  tmp = grub_malloc (tmplen);
+  if (tmp == NULL)
+    return GPG_ERR_OUT_OF_MEMORY;
+
+  grub_memcpy (tmp, S, Slen);
+
+  for (i = 1; i - 1 < l; i++)
+    {
+      grub_memset (T, 0, hLen);
+
+      for (u = 0; u < c; u++)
+	{
+	  if (u == 0)
+	    {
+	      tmp[Slen + 0] = (i & 0xff000000) >> 24;
+	      tmp[Slen + 1] = (i & 0x00ff0000) >> 16;
+	      tmp[Slen + 2] = (i & 0x0000ff00) >> 8;
+	      tmp[Slen + 3] = (i & 0x000000ff) >> 0;
+
+	      rc = grub_crypto_hmac_buffer (md, P, Plen, tmp, tmplen, U);
+	    }
+	  else
+	    rc = grub_crypto_hmac_buffer (md, P, Plen, U, hLen, U);
+
+	  if (rc != GPG_ERR_NO_ERROR)
+	    {
+	      grub_free (tmp);
+	      return rc;
+	    }
+
+	  for (k = 0; k < hLen; k++)
+	    T[k] ^= U[k];
+	}
+
+      grub_memcpy (DK + (i - 1) * hLen, T, i == l ? r : hLen);
+    }
+
+  grub_free (tmp);
+
+  return GPG_ERR_NO_ERROR;
+}