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gc-pbkdf2-sha1
|
From: |
Simon Josefsson |
|
Subject: |
gc-pbkdf2-sha1 |
|
Date: |
Wed, 12 Oct 2005 15:13:28 +0200 |
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User-agent: |
Gnus/5.110004 (No Gnus v0.4) Emacs/22.0.50 (gnu/linux) |
I have installed this. Comments most welcome, as always!
Index: ChangeLog
===================================================================
RCS file: /cvsroot/gnulib/gnulib/ChangeLog,v
retrieving revision 1.415
diff -u -p -r1.415 ChangeLog
--- ChangeLog 12 Oct 2005 01:42:55 -0000 1.415
+++ ChangeLog 12 Oct 2005 13:12:56 -0000
@@ -1,5 +1,11 @@
2005-10-12 Simon Josefsson <address@hidden>
+ * modules/gc-pbkdf2-sha1, modules/gc-pbkdf2-sha1-tests: New files.
+
+ * tests/test-gc-pbkdf2-sha1.c: New file.
+
+2005-10-12 Simon Josefsson <address@hidden>
+
* modules/gc-sha1: New file.
2005-10-12 Simon Josefsson <address@hidden>
Index: lib/ChangeLog
===================================================================
RCS file: /cvsroot/gnulib/gnulib/lib/ChangeLog,v
retrieving revision 1.1009
diff -u -p -r1.1009 ChangeLog
--- lib/ChangeLog 12 Oct 2005 11:57:13 -0000 1.1009
+++ lib/ChangeLog 12 Oct 2005 13:12:57 -0000
@@ -1,5 +1,11 @@
2005-10-12 Simon Josefsson <address@hidden>
+ * gc-pbkdf2-sha1.c: New file.
+
+ * gc.h: Add gc_pbkdf2_sha1 prototype.
+
+2005-10-12 Simon Josefsson <address@hidden>
+
* gc.h, gc-gnulib.c, gc-libgcrypt.c: Use Gc_rc for return types,
suggested by Bruno Haible <address@hidden>.
Index: lib/gc.h
===================================================================
RCS file: /cvsroot/gnulib/gnulib/lib/gc.h,v
retrieving revision 1.7
diff -u -p -r1.7 gc.h
--- lib/gc.h 12 Oct 2005 11:57:13 -0000 1.7
+++ lib/gc.h 12 Oct 2005 13:12:57 -0000
@@ -85,6 +85,19 @@ extern Gc_rc gc_hmac_sha1 (const void *k
const void *in, size_t inlen,
char *resbuf);
+/* Derive cryptographic keys from a password P of length PLEN, with
+ salt S of length SLEN, placing the result in pre-allocated buffer
+ DK of length DKLEN. An iteration count is specified in C, where a
+ larger value means this function take more time (typical iteration
+ counts are 1000-20000). This function "stretches" the key to be
+ exactly dkLen bytes long. GC_OK is returned on success, otherwise
+ an Gc_rc error code is returned. */
+extern Gc_rc
+gc_pbkdf2_sha1 (const char *P, size_t Plen,
+ const char *S, size_t Slen,
+ unsigned int c,
+ char *DK, size_t dkLen);
+
/*
TODO:
Index: lib/gc-pbkdf2-sha1.c
===================================================================
RCS file: lib/gc-pbkdf2-sha1.c
diff -N lib/gc-pbkdf2-sha1.c
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ lib/gc-pbkdf2-sha1.c 12 Oct 2005 13:12:57 -0000
@@ -0,0 +1,187 @@
+/* gc-pbkdf2-sha1.c --- Password-Based Key Derivation Function a'la PKCS#5
+ Copyright (C) 2002, 2003, 2004, 2005 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. The comments in this file are taken
+ from RFC 2898. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "gc.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+/*
+ * 5.2 PBKDF2
+ *
+ * PBKDF2 applies a pseudorandom function (see Appendix B.1 for an
+ * example) to derive keys. The length of the derived key is essentially
+ * unbounded. (However, the maximum effective search space for the
+ * derived key may be limited by the structure of the underlying
+ * pseudorandom function. See Appendix B.1 for further discussion.)
+ * PBKDF2 is recommended for new applications.
+ *
+ * PBKDF2 (P, S, c, dkLen)
+ *
+ * Options: PRF underlying pseudorandom function (hLen
+ * denotes the length in octets of the
+ * pseudorandom function output)
+ *
+ * Input: P password, an octet string (ASCII or UTF-8)
+ * S salt, an octet string
+ * c iteration count, a positive integer
+ * dkLen intended length in octets of the derived
+ * key, a positive integer, at most
+ * (2^32 - 1) * hLen
+ *
+ * Output: DK derived key, a dkLen-octet string
+ */
+
+Gc_rc
+gc_pbkdf2_sha1 (const char *P, size_t Plen,
+ const char *S, size_t Slen,
+ unsigned int c,
+ char *DK, size_t dkLen)
+{
+ unsigned int hLen = 20;
+ char U[20];
+ char T[20];
+ unsigned int u;
+ unsigned int l;
+ unsigned int r;
+ unsigned int i;
+ unsigned int k;
+ int rc;
+
+ if (c == 0)
+ return GC_PKCS5_INVALID_ITERATION_COUNT;
+
+ if (dkLen == 0)
+ return GC_PKCS5_INVALID_DERIVED_KEY_LENGTH;
+
+ /*
+ *
+ * Steps:
+ *
+ * 1. If dkLen > (2^32 - 1) * hLen, output "derived key too long" and
+ * stop.
+ */
+
+ if (dkLen > 4294967295U)
+ return GC_PKCS5_DERIVED_KEY_TOO_LONG;
+
+ /*
+ * 2. Let l be the number of hLen-octet blocks in the derived key,
+ * rounding up, and let r be the number of octets in the last
+ * block:
+ *
+ * l = CEIL (dkLen / hLen) ,
+ * r = dkLen - (l - 1) * hLen .
+ *
+ * Here, CEIL (x) is the "ceiling" function, i.e. the smallest
+ * integer greater than, or equal to, x.
+ */
+
+ l = dkLen / hLen;
+ if (dkLen % hLen)
+ l++;
+ r = dkLen - (l - 1) * hLen;
+
+ /*
+ * 3. For each block of the derived key apply the function F defined
+ * below to the password P, the salt S, the iteration count c, and
+ * the block index to compute the block:
+ *
+ * T_1 = F (P, S, c, 1) ,
+ * T_2 = F (P, S, c, 2) ,
+ * ...
+ * T_l = F (P, S, c, l) ,
+ *
+ * where the function F is defined as the exclusive-or sum of the
+ * first c iterates of the underlying pseudorandom function PRF
+ * applied to the password P and the concatenation of the salt S
+ * and the block index i:
+ *
+ * F (P, S, c, i) = U_1 \xor U_2 \xor ... \xor U_c
+ *
+ * where
+ *
+ * U_1 = PRF (P, S || INT (i)) ,
+ * U_2 = PRF (P, U_1) ,
+ * ...
+ * U_c = PRF (P, U_{c-1}) .
+ *
+ * Here, INT (i) is a four-octet encoding of the integer i, most
+ * significant octet first.
+ *
+ * 4. Concatenate the blocks and extract the first dkLen octets to
+ * produce a derived key DK:
+ *
+ * DK = T_1 || T_2 || ... || T_l<0..r-1>
+ *
+ * 5. Output the derived key DK.
+ *
+ * Note. The construction of the function F follows a "belt-and-
+ * suspenders" approach. The iterates U_i are computed recursively to
+ * remove a degree of parallelism from an opponent; they are exclusive-
+ * ored together to reduce concerns about the recursion degenerating
+ * into a small set of values.
+ *
+ */
+
+ for (i = 1; i <= l; i++)
+ {
+ memset (T, 0, hLen);
+
+ for (u = 1; u <= c; u++)
+ {
+ if (u == 1)
+ {
+ char *tmp;
+ size_t tmplen = Slen + 4;
+
+ tmp = malloc (tmplen);
+ if (tmp == NULL)
+ return GC_MALLOC_ERROR;
+
+ memcpy (tmp, S, Slen);
+ 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 = gc_hmac_sha1 (P, Plen, tmp, tmplen, U);
+
+ free (tmp);
+ }
+ else
+ rc = gc_hmac_sha1 (P, Plen, U, hLen, U);
+
+ if (rc != GC_OK)
+ return rc;
+
+ for (k = 0; k < hLen; k++)
+ T[k] ^= U[k];
+ }
+
+ memcpy (DK + (i - 1) * hLen, T, i == l ? r : hLen);
+ }
+
+ return GC_OK;
+}
Index: m4/ChangeLog
===================================================================
RCS file: /cvsroot/gnulib/gnulib/m4/ChangeLog,v
retrieving revision 1.739
diff -u -p -r1.739 ChangeLog
--- m4/ChangeLog 12 Oct 2005 09:28:48 -0000 1.739
+++ m4/ChangeLog 12 Oct 2005 13:12:58 -0000
@@ -1,5 +1,7 @@
2005-10-12 Simon Josefsson <address@hidden>
+ * gc-pbkdf2-sha1.m4: New file.
+
* gc-hmac-sha1.m4: New file.
* gc-sha1: New file.
Index: m4/gc-pbkdf2-sha1.m4
===================================================================
RCS file: m4/gc-pbkdf2-sha1.m4
diff -N m4/gc-pbkdf2-sha1.m4
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ m4/gc-pbkdf2-sha1.m4 12 Oct 2005 13:12:58 -0000
@@ -0,0 +1,11 @@
+# gc-pbkdf2-sha1.m4 serial 1
+dnl Copyright (C) 2005 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_GC_PBKDF2_SHA1],
+[
+ AC_LIBSOURCES([gc-pbkdf2-sha1.c])
+ AC_LIBOBJ([gc-pbkdf2-sha1])
+])
Index: modules/gc-pbkdf2-sha1
===================================================================
RCS file: modules/gc-pbkdf2-sha1
diff -N modules/gc-pbkdf2-sha1
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ modules/gc-pbkdf2-sha1 12 Oct 2005 13:12:58 -0000
@@ -0,0 +1,24 @@
+Description:
+Password-Based Key Derivation Function according to PKCS#5/RFC2898
+
+Files:
+lib/gc-pbkdf2-sha1.c
+m4/gc-pbkdf2-sha1.m4
+
+Depends-on:
+gc
+gc-hmac-sha1
+
+configure.ac:
+gl_GC_PBKDF2_SHA1
+
+Makefile.am:
+
+Include:
+"gc.h"
+
+License:
+LGPL
+
+Maintainer:
+Simon Josefsson
Index: modules/gc-pbkdf2-sha1-tests
===================================================================
RCS file: modules/gc-pbkdf2-sha1-tests
diff -N modules/gc-pbkdf2-sha1-tests
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ modules/gc-pbkdf2-sha1-tests 12 Oct 2005 13:12:58 -0000
@@ -0,0 +1,11 @@
+Files:
+tests/test-gc-pbkdf2-sha1.c
+
+Depends-on:
+
+configure.ac:
+
+Makefile.am:
+TESTS += test-gc-pbkdf2-sha1
+noinst_PROGRAMS += test-gc-pbkdf2-sha1
+test_gc_pbkdf2_sha1_SOURCES = test-gc-pbkdf2-sha1.c
Index: tests/test-gc-pbkdf2-sha1.c
===================================================================
RCS file: tests/test-gc-pbkdf2-sha1.c
diff -N tests/test-gc-pbkdf2-sha1.c
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ tests/test-gc-pbkdf2-sha1.c 12 Oct 2005 13:12:58 -0000
@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation
+ *
+ * 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. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "gc.h"
+
+#include <stdio.h>
+#include <string.h>
+
+/* Test vectors from RFC 3962. */
+
+#define G_CLEF "\xF0\x9D\x84\x9E"
+
+struct pkcs5
+{
+ int iterations;
+ const char *password;
+ const char *salt;
+ int dklen;
+ const char *expected;
+};
+const struct pkcs5 pkcs5[] = {
+ {1, "password", "ATHENA.MIT.EDUraeburn", 16,
+ "\xCD\xED\xB5\x28\x1B\xB2\xF8\x01\x56\x5A\x11\x22\xB2\x56\x35\x15"},
+ {2, "password", "ATHENA.MIT.EDUraeburn", 16,
+ "\x01\xdb\xee\x7f\x4a\x9e\x24\x3e\x98\x8b\x62\xc7\x3c\xda\x93\x5d"},
+ {2, "password", "ATHENA.MIT.EDUraeburn", 32,
+ "\x01\xdb\xee\x7f\x4a\x9e\x24\x3e\x98\x8b\x62\xc7\x3c\xda\x93\x5d"
+ "\xa0\x53\x78\xb9\x32\x44\xec\x8f\x48\xa9\x9e\x61\xad\x79\x9d\x86"},
+ {1200, "password", "ATHENA.MIT.EDUraeburn", 16,
+ "\x5c\x08\xeb\x61\xfd\xf7\x1e\x4e\x4e\xc3\xcf\x6b\xa1\xf5\x51\x2b"},
+ {1200, "password", "ATHENA.MIT.EDUraeburn", 32,
+ "\x5c\x08\xeb\x61\xfd\xf7\x1e\x4e\x4e\xc3\xcf\x6b\xa1\xf5\x51\x2b"
+ "\xa7\xe5\x2d\xdb\xc5\xe5\x14\x2f\x70\x8a\x31\xe2\xe6\x2b\x1e\x13"},
+ {5, "password", "\x12\x34\x56\x78\x78\x56\x34\x12\x00", 16,
+ "\xd1\xda\xa7\x86\x15\xf2\x87\xe6\xa1\xc8\xb1\x20\xd7\x06\x2a\x49"},
+ {5, "password", "\x12\x34\x56\x78\x78\x56\x34\x12\x00", 32,
+ "\xd1\xda\xa7\x86\x15\xf2\x87\xe6\xa1\xc8\xb1\x20\xd7\x06\x2a\x49"
+ "\x3f\x98\xd2\x03\xe6\xbe\x49\xa6\xad\xf4\xfa\x57\x4b\x6e\x64\xee"},
+ {1200, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
+ "pass phrase equals block size", 16,
+ "\x13\x9c\x30\xc0\x96\x6b\xc3\x2b\xa5\x5f\xdb\xf2\x12\x53\x0a\xc9"},
+ {1200, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
+ "pass phrase equals block size", 32,
+ "\x13\x9c\x30\xc0\x96\x6b\xc3\x2b\xa5\x5f\xdb\xf2\x12\x53\x0a\xc9"
+ "\xc5\xec\x59\xf1\xa4\x52\xf5\xcc\x9a\xd9\x40\xfe\xa0\x59\x8e\xd1"},
+ {1200, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
+ "pass phrase exceeds block size", 16,
+ "\x9c\xca\xd6\xd4\x68\x77\x0c\xd5\x1b\x10\xe6\xa6\x87\x21\xbe\x61"},
+ {1200, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
+ "pass phrase exceeds block size", 32,
+ "\x9c\xca\xd6\xd4\x68\x77\x0c\xd5\x1b\x10\xe6\xa6\x87\x21\xbe\x61"
+ "\x1a\x8b\x4d\x28\x26\x01\xdb\x3b\x36\xbe\x92\x46\x91\x5e\xc8\x2a"},
+ {50, G_CLEF "\x00", "EXAMPLE.COMpianist", 16,
+ "\x6b\x9c\xf2\x6d\x45\x45\x5a\x43\xa5\xb8\xbb\x27\x6a\x40\x3b\x39"},
+ {50, G_CLEF "\x00", "EXAMPLE.COMpianist", 32,
+ "\x6b\x9c\xf2\x6d\x45\x45\x5a\x43\xa5\xb8\xbb\x27\x6a\x40\x3b\x39"
+ "\xe7\xfe\x37\xa0\xc4\x1e\x02\xc2\x81\xff\x30\x69\xe1\xe9\x4f\x52"},
+ {500, "All n-entities must communicate with other n-entities via n-1 "
+ "entiteeheehees", "\x12\x34\x56\x78\x78\x56\x34\x12\x00", 16,
+ "\x6A\x89\x70\xBF\x68\xC9\x2C\xAE\xA8\x4A\x8D\xF2\x85\x10\x85\x86"}
+};
+
+int
+main (int argc, char *argv[])
+{
+ size_t i;
+ int rc;
+ char out[BUFSIZ];
+
+ for (i = 0; i < sizeof (pkcs5) / sizeof (pkcs5[0]); i++)
+ {
+ rc = gc_pbkdf2_sha1 (pkcs5[i].password, strlen (pkcs5[i].password),
+ pkcs5[i].salt, strlen (pkcs5[i].salt),
+ pkcs5[i].iterations, out, pkcs5[i].dklen);
+ if (rc != GC_OK)
+ {
+ printf ("PKCS5 entry %d failed fatally: %d\n", i, rc);
+ return 1;
+ }
+
+ if (memcmp (pkcs5[i].expected, out, pkcs5[i].dklen) != 0)
+ {
+ printf ("PKCS5 entry %d failed\n", i);
+ return 1;
+ }
+ }
+
+ return 0;
+}
- gc-pbkdf2-sha1,
Simon Josefsson <=