HKDF (does not work yet)

4 files changed, 423 insertions, 0 deletions

diff --git a/src/include/gnunet_crypto_lib.h b/src/include/gnunet_crypto_lib.h
index d31dfcfa6..479e0e42d 100644
--- a/src/include/gnunet_crypto_lib.h
+++ b/src/include/gnunet_crypto_lib.h
@@ -512,6 +512,27 @@ int GNUNET_CRYPTO_hash_xorcmp (const GNUNET_HashCode * h1,
 
 
 /**
+ * @brief Derive key
+ * @param xtr_algo hash algorithm for the extraction phase, GCRY_MD_...
+ * @param prf_algo hash algorithm for the expansion phase, GCRY_MD_...
+ * @param xts salt
+ * @param xts_len length of xts
+ * @param skm source key material
+ * @param skm_len length of skm
+ * @param ctx context info
+ * @param ctx_len length of ctx
+ * @param out_len desired length of the derived key
+ * @param result buffer for the derived key, allocated by caller
+ * @return GNUNET_YES on success
+ */
+int
+GNUNET_CRYPTO_hkdf (int xtr_algo, int prf_algo, const void *xts,
+    const size_t xts_len, const void *skm, const size_t skm_len,
+    const void *ctx, const size_t ctx_len, const unsigned long long out_len,
+    void *result);
+
+
+/**
  * Create a new private key. Caller must free return value.
  *
  * @return fresh private key
diff --git a/src/util/Makefile.am b/src/util/Makefile.am
index 9cc402fc5..0b878c673 100644
--- a/src/util/Makefile.am
+++ b/src/util/Makefile.am
@@ -40,6 +40,7 @@ libgnunetutil_la_SOURCES = \
   crypto_aes.c \
   crypto_crc.c \
   crypto_hash.c \
+  crypto_hkdf.c \
   crypto_ksk.c \
   crypto_random.c \
   crypto_rsa.c \
@@ -112,6 +113,7 @@ check_PROGRAMS = \
  test_crypto_aes_weak \
  test_crypto_crc \
  test_crypto_hash \
+# test_crypto_hkdf \
  test_crypto_ksk \
  test_crypto_random \
  test_crypto_rsa \
@@ -227,6 +229,11 @@ test_crypto_hash_SOURCES = \
 test_crypto_hash_LDADD = \
  $(top_builddir)/src/util/libgnunetutil.la  
 
+test_crypto_hkdf_SOURCES = \
+ test_crypto_hkdf.c
+test_crypto_hkdf_LDADD = \
+ $(top_builddir)/src/util/libgnunetutil.la  
+
 test_crypto_ksk_SOURCES = \
  test_crypto_ksk.c
 test_crypto_ksk_LDADD = \
diff --git a/src/util/crypto_hkdf.c b/src/util/crypto_hkdf.c
new file mode 100644
index 000000000..efde3b868
--- /dev/null
+++ b/src/util/crypto_hkdf.c
@@ -0,0 +1,192 @@
+/*
+    Copyright (c) 2010 Nils Durner
+
+    Permission is hereby granted, free of charge, to any person obtaining a copy
+    of this software and associated documentation files (the "Software"), to deal
+    in the Software without restriction, including without limitation the rights
+    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+    copies of the Software, and to permit persons to whom the Software is
+    furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included in
+    all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+    THE SOFTWARE.
+*/
+
+/**
+ * @file src/util/crypto_hkdf.c
+ * @brief Hash-based KDF as defined in draft-krawczyk-hkdf-01
+ * @see http://tools.ietf.org/html/draft-krawczyk-hkdf-01
+ * @author Nils Durner
+ */
+
+#include "platform.h"
+#include "gnunet_crypto_lib.h"
+
+/**
+ * @brief Compute the HMAC
+ * @param mac gcrypt MAC handle
+ * @param key HMAC key
+ * @param key_len length of key
+ * @param buf message to be processed
+ * @param buf_len length of buf
+ * @return HMAC, freed by caller via gcry_md_close/_reset
+ */
+static void *
+doHMAC (gcry_md_hd_t mac, const void *key, const size_t key_len,
+    const void *buf, const size_t buf_len)
+{
+  gcry_md_setkey (mac, key, key_len);
+  gcry_md_write (mac, buf, buf_len);
+
+  return (void *) gcry_md_read (mac, 0);
+}
+
+/**
+ * @brief Generate pseudo-random key
+ * @param mac gcrypt HMAC handle
+ * @param xts salt
+ * @param xts_len length of the salt
+ * @param skm source key material
+ * @param skm_len length of skm
+ * @param prk result buffer (allocated by caller; at least gcry_md_dlen() bytes)
+ * @return GNUNET_YES on success
+ */
+static int
+getPRK (gcry_md_hd_t mac, const void *xts, const unsigned long long xts_len,
+    const void *skm, const unsigned long long skm_len, void *prk)
+{
+  void *ret;
+
+  ret = doHMAC (mac, xts, xts_len, skm, skm_len);
+  if (ret == NULL)
+    return GNUNET_SYSERR;
+  memcpy (prk, ret, gcry_md_get_algo_dlen (gcry_md_get_algo (mac)));
+
+  return GNUNET_YES;
+}
+
+static void dump(void *p, unsigned int l)
+{
+  unsigned int i;
+
+  printf("\n");
+  for (i = 0; i < l; i++)
+    {
+      printf("%2x", ((char *) p)[i]);
+    }
+  printf("\n");
+}
+
+/**
+ * @brief Derive key
+ * @param xtr_algo hash algorithm for the extraction phase, GCRY_MD_...
+ * @param prf_algo hash algorithm for the expansion phase, GCRY_MD_...
+ * @param xts salt
+ * @param xts_len length of xts
+ * @param skm source key material
+ * @param skm_len length of skm
+ * @param ctx context info
+ * @param ctx_len length of ctx
+ * @param out_len desired length of the derived key
+ * @param result buffer for the derived key, allocated by caller
+ * @return GNUNET_YES on success
+ */
+int
+GNUNET_CRYPTO_hkdf (int xtr_algo, int prf_algo, const void *xts,
+    const size_t xts_len, const void *skm, const size_t skm_len,
+    const void *ctx, const size_t ctx_len, const unsigned long long out_len,
+    void *result)
+{
+  void *prk, *hc, *plain;
+  unsigned long long plain_len;
+  unsigned long i, t, d;
+  unsigned int k, xtr_len;
+  int ret;
+  gcry_md_hd_t xtr, prf;
+
+  prk = plain = NULL;
+  xtr_len = gcry_md_get_algo_dlen (xtr_algo);
+  k = gcry_md_get_algo_dlen (prf_algo);
+  gcry_md_open(&xtr, xtr_algo, GCRY_MD_FLAG_HMAC);
+  gcry_md_open(&prf, prf_algo, GCRY_MD_FLAG_HMAC);
+
+  if (out_len > (2 ^ 32 * k) || !xtr_algo || !prf_algo)
+    return GNUNET_SYSERR;
+
+  prk = GNUNET_malloc (xtr_len);
+
+  memset (result, 0, out_len);
+  gcry_md_reset (xtr);
+  if (getPRK (xtr, xts, xts_len, skm, skm_len, prk)
+      != GNUNET_YES)
+    goto hkdf_error;
+dump(prk, xtr_len);
+
+  /* K(1) */
+  plain_len = k + ctx_len + 4;
+  plain = GNUNET_malloc (plain_len);
+  memset (plain, 0, k);
+  memcpy (plain + k, ctx, ctx_len);
+  t = out_len / k;
+  if (t > 0)
+    {
+      memset (plain + k + ctx_len, 0, 4);
+      gcry_md_reset (prf);
+      hc = doHMAC (prf, prk, k, plain, plain_len);
+      if (hc == NULL)
+        goto hkdf_error;
+      memcpy (result, hc, k);
+      result += k;
+    }
+
+  /* K(i+1) */
+  for (i = 1; i < t; i++)
+    {
+      memcpy (plain, result - k, k);
+      memcpy (plain + k + ctx_len, &i, 4);
+      gcry_md_reset (prf);
+      hc = doHMAC (prf, prk, k, plain, plain_len);
+      if (hc == NULL)
+        goto hkdf_error;
+      memcpy (result, hc, k);
+      result += k;
+    }
+
+  /* K(t):d */
+  d = out_len % k;
+  if (d > 0)
+    {
+      if (t > 0)
+        memcpy (plain, result - k, k);
+      memcpy (plain + k + ctx_len, &i, 4);
+      gcry_md_reset (prf);
+      hc = doHMAC (prf, prk, k, plain, plain_len);
+      if (hc == NULL)
+        goto hkdf_error;
+      memcpy (result, hc, d);
+    }
+
+  ret = GNUNET_YES;
+  goto hkdf_ok;
+
+hkdf_error:
+  ret = GNUNET_SYSERR;
+hkdf_ok:
+  GNUNET_free (prk);
+  GNUNET_free_non_null (plain);
+  gcry_md_close (prf);
+  gcry_md_close (xtr);
+
+  return ret;
+}
+
+
+/* end of crypto_hkdf.c */
diff --git a/src/util/test_crypto_hkdf.c b/src/util/test_crypto_hkdf.c
new file mode 100644
index 000000000..d0078202d
--- /dev/null
+++ b/src/util/test_crypto_hkdf.c
@@ -0,0 +1,203 @@
+/*
+    Copyright (c) 2010 Nils Durner
+
+    Permission is hereby granted, free of charge, to any person obtaining a copy
+    of this software and associated documentation files (the "Software"), to deal
+    in the Software without restriction, including without limitation the rights
+    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+    copies of the Software, and to permit persons to whom the Software is
+    furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included in
+    all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+    THE SOFTWARE.
+*/
+
+/**
+ * @file src/util/test_crypt_hkdf.c
+ * @brief Testcases for HKDF
+ * @author Nils Durner
+ */
+
+#include "platform.h"
+#include "gnunet_crypto_lib.h"
+
+void
+tc1 ()
+{
+  char ikm[22] = { 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
+      0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b };
+  char salt[13] = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
+      0x0a, 0x0b, 0x0c };
+  char
+      info[10] = { 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9 };
+  char okm[42] = { 0x3c, 0xb2, 0x5f, 0x25, 0xfa, 0xac, 0xd5, 0x7a, 0x90, 0x43,
+      0x4f, 0x64, 0xd0, 0x36, 0x2f, 0x2a, 0x2d, 0x2d, 0x0a, 0x90, 0xcf, 0x1a,
+      0x5a, 0x4c, 0x5d, 0xb0, 0x2d, 0x56, 0xec, 0xc4, 0xc5, 0xbf, 0x34, 0x00,
+      0x72, 0x08, 0xd5, 0xb8, 0x87, 0x18, 0x58, 0x65 };
+  char result[44];
+  int l = 42;
+
+  GNUNET_assert (GNUNET_CRYPTO_hkdf(GCRY_MD_SHA256, GCRY_MD_SHA256, salt, sizeof(salt), ikm, sizeof(ikm), info, sizeof(info),
+          l, result) == GNUNET_YES);
+  GNUNET_assert (memcmp(result, okm, l) == 0);
+  GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
+}
+
+void
+tc2 ()
+{
+  char ikm[80] = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
+      0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
+      0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21,
+      0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d,
+      0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
+      0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45,
+      0x46, 0x47, 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f };
+  char salt[80] = { 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
+      0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75,
+      0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81,
+      0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d,
+      0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99,
+      0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5,
+      0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf };
+  char info[80] = { 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9,
+      0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5,
+      0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, 0xd0, 0xd1,
+      0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd,
+      0xde, 0xdf, 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
+      0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5,
+      0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff };
+  char okm[82] = { 0xb1, 0x1e, 0x39, 0x8d, 0xc8, 0x03, 0x27, 0xa1, 0xc8, 0xe7,
+      0xf7, 0x8c, 0x59, 0x6a, 0x49, 0x34, 0x4f, 0x01, 0x2e, 0xda, 0x2d, 0x4e,
+      0xfa, 0xd8, 0xa0, 0x50, 0xcc, 0x4c, 0x19, 0xaf, 0xa9, 0x7c, 0x59, 0x04,
+      0x5a, 0x99, 0xca, 0xc7, 0x82, 0x72, 0x71, 0xcb, 0x41, 0xc6, 0x5e, 0x59,
+      0x0e, 0x09, 0xda, 0x32, 0x75, 0x60, 0x0c, 0x2f, 0x09, 0xb8, 0x36, 0x77,
+      0x93, 0xa9, 0xac, 0xa3, 0xdb, 0x71, 0xcc, 0x30, 0xc5, 0x81, 0x79, 0xec,
+      0x3e, 0x87, 0xc1, 0x4c, 0x01, 0xd5, 0xc1, 0xf3, 0x43, 0x4f, 0x1d, 0x87 };
+  char result[84];
+  int l = 82;
+
+  GNUNET_assert (GNUNET_CRYPTO_hkdf(GCRY_MD_SHA256, GCRY_MD_SHA256, salt, sizeof(salt), ikm, sizeof(ikm), info, sizeof(info),
+          l, result) == GNUNET_YES);
+  GNUNET_assert (memcmp(result, okm, l) == 0);
+  GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
+}
+
+void
+tc3 ()
+{
+  char ikm[80] = { 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
+      0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b };
+  char okm[42] = { 0x8d, 0xa4, 0xe7, 0x75, 0xa5, 0x63, 0xc1, 0x8f, 0x71, 0x5f,
+      0x80, 0x2a, 0x06, 0x3c, 0x5a, 0x31, 0xb8, 0xa1, 0x1f, 0x5c, 0x5e, 0xe1,
+      0x87, 0x9e, 0xc3, 0x45, 0x4e, 0x5f, 0x3c, 0x73, 0x8d, 0x2d, 0x9d, 0x20,
+      0x13, 0x95, 0xfa, 0xa4, 0xb6, 0x1a, 0x96, 0xc8 };
+  char result[44];
+  int l = 42;
+
+  GNUNET_assert (GNUNET_CRYPTO_hkdf(GCRY_MD_SHA256, GCRY_MD_SHA256, NULL, 0, ikm, sizeof(ikm), NULL, 0,
+          l, result) == GNUNET_YES);
+  GNUNET_assert (memcmp(result, okm, l) == 0);
+  GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
+}
+
+void
+tc4 ()
+{
+  char ikm[11] = { 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
+      0x0b };
+  char salt[13] = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
+      0x0a, 0x0b, 0x0c };
+  char
+      info[10] = { 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9 };
+  char okm[42] = { 0x08, 0x5a, 0x01, 0xea, 0x1b, 0x10, 0xf3, 0x69, 0x33, 0x06,
+      0x8b, 0x56, 0xef, 0xa5, 0xad, 0x81, 0xa4, 0xf1, 0x4b, 0x82, 0x2f, 0x5b,
+      0x09, 0x15, 0x68, 0xa9, 0xcd, 0xd4, 0xf1, 0x55, 0xfd, 0xa2, 0xc2, 0x2e,
+      0x42, 0x24, 0x78, 0xd3, 0x05, 0xf3, 0xf8, 0x96 };
+  char result[84];
+  int l = 42;
+
+  GNUNET_assert (GNUNET_CRYPTO_hkdf(GCRY_MD_SHA1, GCRY_MD_SHA1, salt, sizeof(salt), ikm, sizeof(ikm), info, sizeof(info),
+          l, result) == GNUNET_YES);
+  GNUNET_assert (memcmp(result, okm, l) == 0);
+  GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
+}
+
+void
+tc5 ()
+{
+  char ikm[80] = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
+      0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15,
+      0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21,
+      0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d,
+      0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
+      0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45,
+      0x46, 0x47, 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f };
+  char salt[80] = { 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
+      0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75,
+      0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81,
+      0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d,
+      0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99,
+      0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5,
+      0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf };
+  char info[80] = { 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9,
+      0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5,
+      0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, 0xd0, 0xd1,
+      0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd,
+      0xde, 0xdf, 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
+      0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5,
+      0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff };
+  char okm[82] = { 0x0b, 0xd7, 0x70, 0xa7, 0x4d, 0x11, 0x60, 0xf7, 0xc9, 0xf1,
+      0x2c, 0xd5, 0x91, 0x2a, 0x06, 0xeb, 0xff, 0x6a, 0xdc, 0xae, 0x89, 0x9d,
+      0x92, 0x19, 0x1f, 0xe4, 0x30, 0x56, 0x73, 0xba, 0x2f, 0xfe, 0x8f, 0xa3,
+      0xf1, 0xa4, 0xe5, 0xad, 0x79, 0xf3, 0xf3, 0x34, 0xb3, 0xb2, 0x02, 0xb2,
+      0x17, 0x3c, 0x48, 0x6e, 0xa3, 0x7c, 0xe3, 0xd3, 0x97, 0xed, 0x03, 0x4c,
+      0x7f, 0x9d, 0xfe, 0xb1, 0x5c, 0x5e, 0x92, 0x73, 0x36, 0xd0, 0x44, 0x1f,
+      0x4c, 0x43, 0x00, 0xe2, 0xcf, 0xf0, 0xd0, 0x90, 0x0b, 0x52, 0xd3, 0xb4 };
+  char result[84];
+  int l = 82;
+
+  GNUNET_assert (GNUNET_CRYPTO_hkdf(GCRY_MD_SHA1, GCRY_MD_SHA1, salt, sizeof(salt), ikm, sizeof(ikm), info, sizeof(info),
+          l, result) == GNUNET_YES);
+  GNUNET_assert (memcmp(result, okm, l) == 0);
+  GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
+}
+
+void
+tc6 ()
+{
+  char ikm[22] = { 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
+      0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b };
+  char okm[82] = { 0x0a, 0xc1, 0xaf, 0x70, 0x02, 0xb3, 0xd7, 0x61, 0xd1, 0xe5,
+      0x52, 0x98, 0xda, 0x9d, 0x05, 0x06, 0xb9, 0xae, 0x52, 0x05, 0x72, 0x20,
+      0xa3, 0x06, 0xe0, 0x7b, 0x6b, 0x87, 0xe8, 0xdf, 0x21, 0xd0, 0xea, 0x00,
+      0x03, 0x3d, 0xe0, 0x39, 0x84, 0xd3, 0x49, 0x18 };
+  char result[84];
+  int l = 82;
+
+  GNUNET_assert (GNUNET_CRYPTO_hkdf(GCRY_MD_SHA1, GCRY_MD_SHA1, NULL, 0, ikm, sizeof(ikm), NULL, 0,
+          l, result) == GNUNET_YES);
+  GNUNET_assert (memcmp(result, okm, l) == 0);
+  GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
+}
+
+int
+main ()
+{
+  GNUNET_log_setup ("test-crypto-hkdf", "WARNING", NULL);
+  tc1();
+  tc2();
+  tc3();
+  tc4();
+  tc5();
+  tc6();
+  return 0;
+}