3 files changed, 103 insertions, 27 deletions

diff --git a/src/include/gnunet_crypto_lib.h b/src/include/gnunet_crypto_lib.h
index 8a8e71a96..126c599b9 100644
--- a/src/include/gnunet_crypto_lib.h
+++ b/src/include/gnunet_crypto_lib.h
@@ -527,6 +527,8 @@ int GNUNET_CRYPTO_hash_xorcmp (const GNUNET_HashCode * h1,
 
 /**
  * @brief Derive key
+ * @param result buffer for the derived key, allocated by caller
+ * @param out_len desired length of the derived 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
@@ -535,15 +537,12 @@ int GNUNET_CRYPTO_hash_xorcmp (const GNUNET_HashCode * h1,
  * @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);
+GNUNET_CRYPTO_hkdf (void *result, const unsigned long long out_len,
+    int xtr_algo, int prf_algo, const void *xts, const size_t xts_len,
+    const void *skm, const size_t skm_len, ...);
 
 
 /**
diff --git a/src/util/crypto_hkdf.c b/src/util/crypto_hkdf.c
index e442aef1c..4415b7551 100644
--- a/src/util/crypto_hkdf.c
+++ b/src/util/crypto_hkdf.c
@@ -93,6 +93,8 @@ static void dump(char *src, void *p, unsigned int l)
 
 /**
  * @brief Derive key
+ * @param result buffer for the derived key, allocated by caller
+ * @param out_len desired length of the derived 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
@@ -101,15 +103,12 @@ static void dump(char *src, void *p, unsigned int l)
  * @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)
+GNUNET_CRYPTO_hkdf (void *result, const unsigned long long out_len,
+    int xtr_algo, int prf_algo, const void *xts, const size_t xts_len,
+    const void *skm, const size_t skm_len, ...)
 {
   void *prk, *hc, *plain;
   unsigned long long plain_len;
@@ -117,6 +116,8 @@ GNUNET_CRYPTO_hkdf (int xtr_algo, int prf_algo, const void *xts,
   unsigned int k, xtr_len;
   int ret;
   gcry_md_hd_t xtr, prf;
+  size_t ctx_len;
+  va_list argp;
 
   prk = plain = NULL;
   xtr_len = gcry_md_get_algo_dlen (xtr_algo);
@@ -127,6 +128,11 @@ GNUNET_CRYPTO_hkdf (int xtr_algo, int prf_algo, const void *xts,
   if (out_len > (2 ^ 32 * k) || !xtr_algo || !prf_algo)
     return GNUNET_SYSERR;
 
+  va_start(argp, skm_len);
+  for (ctx_len = 0; va_arg (argp, void *);)
+    ctx_len += va_arg (argp, size_t);
+  va_end(argp);
+
   prk = GNUNET_malloc (xtr_len);
 
   memset (result, 0, out_len);
@@ -146,8 +152,21 @@ GNUNET_CRYPTO_hkdf (int xtr_algo, int prf_algo, const void *xts,
   plain = GNUNET_malloc (plain_len);
   if (t > 0)
     {
-      memcpy (plain, ctx, ctx_len);
-      memset (plain + ctx_len, 1, 1);
+      void *ctx, *dst;
+
+      dst = plain;
+      va_start (argp, skm_len);
+      while ((ctx = va_arg (argp, void *)))
+        {
+          size_t len;
+
+          len = va_arg (argp, size_t);
+          memcpy (dst, ctx, len);
+          dst += len;
+        }
+      va_end (argp);
+
+      memset (dst, 1, 1);
       gcry_md_reset (prf);
 #if DEBUG_HKDF
       dump("K(1)", plain, plain_len);
@@ -160,7 +179,15 @@ GNUNET_CRYPTO_hkdf (int xtr_algo, int prf_algo, const void *xts,
     }
 
   if (t > 1 || d > 0)
-    memcpy (plain + k, ctx, ctx_len);
+    {
+      void *ctx, *dst;
+
+      dst = plain + k;
+      va_start(argp, skm_len);
+      while ((ctx = va_arg (argp, void *)))
+        memcpy (dst, ctx, va_arg (argp, size_t));
+      va_end (argp);
+    }
 
   /* K(i+1) */
   for (i = 1; i < t; i++)
diff --git a/src/util/test_crypto_hkdf.c b/src/util/test_crypto_hkdf.c
index ec215fd34..1b4d368aa 100644
--- a/src/util/test_crypto_hkdf.c
+++ b/src/util/test_crypto_hkdf.c
@@ -48,8 +48,8 @@ tc1 ()
   int l = 42;
 
   memset (result, 0, sizeof(result));
-  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 (GNUNET_CRYPTO_hkdf(result, l, GCRY_MD_SHA256, GCRY_MD_SHA256, salt, sizeof(salt), ikm, sizeof(ikm), info, sizeof(info),
+          NULL) == GNUNET_YES);
   GNUNET_assert (memcmp(result, okm, l) == 0);
   GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
 }
@@ -89,8 +89,8 @@ tc2 ()
   int l = 82;
 
   memset (result, 0, sizeof(result));
-  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 (GNUNET_CRYPTO_hkdf(result, l, GCRY_MD_SHA256, GCRY_MD_SHA256, salt, sizeof(salt), ikm, sizeof(ikm), info, sizeof(info),
+          NULL) == GNUNET_YES);
   GNUNET_assert (memcmp(result, okm, l) == 0);
   GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
 }
@@ -108,8 +108,8 @@ tc3 ()
   int l = 42;
 
   memset (result, 0, sizeof(result));
-  GNUNET_assert (GNUNET_CRYPTO_hkdf(GCRY_MD_SHA256, GCRY_MD_SHA256, NULL, 0, ikm, sizeof(ikm), NULL, 0,
-          l, result) == GNUNET_YES);
+  GNUNET_assert (GNUNET_CRYPTO_hkdf(result, l, GCRY_MD_SHA256, GCRY_MD_SHA256, NULL, 0, ikm, sizeof(ikm), NULL, 0,
+          NULL) == GNUNET_YES);
   GNUNET_assert (memcmp(result, okm, l) == 0);
   GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
 }
@@ -131,8 +131,8 @@ tc4 ()
   int l = 42;
 
   memset (result, 0, sizeof(result));
-  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 (GNUNET_CRYPTO_hkdf(result, l, GCRY_MD_SHA1, GCRY_MD_SHA1, salt, sizeof(salt), ikm, sizeof(ikm), info, sizeof(info),
+          NULL) == GNUNET_YES);
   GNUNET_assert (memcmp(result, okm, l) == 0);
   GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
 }
@@ -172,8 +172,8 @@ tc5 ()
   int l = 82;
 
   memset (result, 0, sizeof(result));
-  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 (GNUNET_CRYPTO_hkdf(result, l, GCRY_MD_SHA1, GCRY_MD_SHA1, salt, sizeof(salt), ikm, sizeof(ikm), info, sizeof(info),
+          NULL) == GNUNET_YES);
   GNUNET_assert (memcmp(result, okm, l) == 0);
   GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
 }
@@ -191,8 +191,52 @@ tc6 ()
   int l = 42;
 
   memset (result, 0, sizeof(result));
-  GNUNET_assert (GNUNET_CRYPTO_hkdf(GCRY_MD_SHA1, GCRY_MD_SHA1, NULL, 0, ikm, sizeof(ikm), NULL, 0,
-          l, result) == GNUNET_YES);
+  GNUNET_assert (GNUNET_CRYPTO_hkdf(result, l, GCRY_MD_SHA1, GCRY_MD_SHA1, NULL, 0, ikm, sizeof(ikm), NULL, 0,
+          NULL) == GNUNET_YES);
+  GNUNET_assert (memcmp(result, okm, l) == 0);
+  GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
+}
+
+void
+tc7 ()
+{
+  unsigned 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 };
+  unsigned 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 };
+  unsigned char info1[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 };
+  unsigned char info2[80] = { 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 };
+  unsigned 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;
+
+  memset (result, 0, sizeof(result));
+  GNUNET_assert (GNUNET_CRYPTO_hkdf(result, l, GCRY_MD_SHA1, GCRY_MD_SHA1, salt,
+      sizeof(salt), ikm, sizeof(ikm), info1, sizeof(info1), info2, sizeof(info2),
+      NULL) == GNUNET_YES);
   GNUNET_assert (memcmp(result, okm, l) == 0);
   GNUNET_assert (memcmp(result + l, "\0", 2) == 0);
 }
@@ -201,11 +245,17 @@ int
 main ()
 {
   GNUNET_log_setup ("test-crypto-hkdf", "WARNING", NULL);
+
+  /* Official test vectors */
   tc1();
   tc2();
   tc3();
   tc4();
   tc5();
   tc6();
+
+  /* Additional tests */
+  tc7();
+
   return 0;
 }