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Diffstat (limited to 'grub-core/lib/pbkdf2.c')
| -rw-r--r-- | grub-core/lib/pbkdf2.c | 109 |
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; +} |