Implemented HKDF. Moved small-primes into it's own file because it was breaking

the clojure editor in eclipse. Re-wrote generate-aes-key! using
javax.crypto.KeyGenerator.

2 files changed, 137 insertions, 98 deletions

diff --git a/src/org/gnu/clojure/gnunet/crypto.clj b/src/org/gnu/clojure/gnunet/crypto.clj
index ffcc936..038c564 100644
--- a/src/org/gnu/clojure/gnunet/crypto.clj
+++ b/src/org/gnu/clojure/gnunet/crypto.clj
@@ -1,11 +1,11 @@
 (ns org.gnu.clojure.gnunet.crypto
-  (:use (org.gnu.clojure.gnunet parser message)
+  (:use (org.gnu.clojure.gnunet parser message primes)
     clojure.contrib.monads clojure.test)
-  (:import (java.security KeyPairGenerator KeyFactory MessageDigest Signature)
+  (:import java.math.BigInteger
+    (java.security KeyPairGenerator KeyFactory MessageDigest Signature)
     (java.security.spec RSAKeyGenParameterSpec RSAPublicKeySpec
                         RSAPrivateCrtKeySpec)
-    java.math.BigInteger
-    (javax.crypto Cipher SecretKeyFactory)
+    (javax.crypto Cipher KeyGenerator SecretKeyFactory Mac)
     javax.crypto.spec.SecretKeySpec))
 
 (def signature-size 256)
@@ -14,11 +14,55 @@
 
 (defn generate-aes-key!
   [random]
-  (let [buffer (byte-array (repeat aes-key-size (byte 0)))
-        _ (.nextBytes random buffer)
-        key-spec (SecretKeySpec. buffer "AES")
-        key-factory (SecretKeyFactory/getInstance "AES")]
-    (.generateSecret key-factory key-spec)))
+  (.generateKey (doto (KeyGenerator/getInstance "AES")
+                  (.init (* 8 aes-key-size) random))))
+
+(defn sha-512
+  "Compute the SHA-512 digest of a sequence of bytes."
+  [byte-seq]
+  (.digest (MessageDigest/getInstance "SHA-512") (byte-array byte-seq)))
+
+(defn hmac-sha-512
+  [key-seq byte-seq]
+  (let [hmac-key (SecretKeySpec. (byte-array key-seq) "HmacSHA512")
+        hmac (doto (Mac/getInstance "HmacSHA512") (.init hmac-key))]
+    (.doFinal hmac (byte-array byte-seq))))
+
+(defn hmac-sha-256
+  [key-seq byte-seq]
+  (let [hmac-key (SecretKeySpec. (byte-array key-seq) "HmacSHA256")
+        hmac (doto (Mac/getInstance "HmacSHA256") (.init hmac-key))]
+    (.doFinal hmac (byte-array byte-seq))))
+
+(with-test
+(defn hkdf
+  "HMAC-based Extract-and-Expand Key Derivation Function (HKDF)
+   http://tools.ietf.org/html/rfc5869"
+  [hmac-extract hmac-expand key-material salt info output-length]
+  (let [salt (if (empty? salt) [(byte 0)] salt)
+        pseudorandom-key (hmac-extract salt key-material)
+        generator (fn [x]
+                    (let [[input counter] x
+                          counter (.byteValue (inc counter))]
+                      [(hmac-expand pseudorandom-key
+                         (concat input info [counter]))
+                       counter]))
+        keying-material (mapcat first (iterate generator [[] 0]))]
+    (take output-length keying-material)))
+;; A.1.  Test Case 1
+(is (= (let [ikm (encode-int 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b)
+             salt (concat [(byte 0)] (encode-int 0x0102030405060708090a0b0c))
+             info (encode-int 0xf0f1f2f3f4f5f6f7f8f9)
+             l 42]
+         (hkdf hmac-sha-256 hmac-sha-256 ikm salt info l))
+      (encode-int 0x3cb25f25faacd57a90434f64d0362f2a2d2d0a90cf1a5a4c5db02d56ecc4c5bf34007208d5b887185865)))
+;; A.3.  Test Case 3
+(is (= (let [ikm (encode-int 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b)
+             salt []
+             info []
+             l 42]
+         (hkdf hmac-sha-256 hmac-sha-256 ikm salt info l))
+      (encode-int 0x8da4e775a563c18f715f802a063c5a31b8a11f5c5ee1879ec3454e5f3c738d2d9d201395faa4b61a96c8))))
 
 (defn encode-signed
   [purpose inner-material]
@@ -97,10 +141,6 @@
       (byte-array byte-seq))
     (catch Exception e nil)))
 
-(defn sha-512
-  "Compute the SHA-512 digest of a sequence of bytes."
-  [byte-seq]
-  (.digest (MessageDigest/getInstance "SHA-512") (byte-array byte-seq)))
 
 (def rsa-modulus-length 256)
 (def rsa-exponent-length 2)
@@ -142,7 +182,7 @@
   {:pre [(> bit-length 0)]}
   (let [cnt (quot (+ bit-length 511) 512)
         hashes (iterate sha-512 seed)
-        number (BigInteger. 1 (byte-array (mapcat identity (take cnt hashes))))
+        number (BigInteger. 1 (byte-array (apply concat (take cnt hashes))))
         len (.bitLength number)
         number (reduce bit-clear number (range (dec len) (dec bit-length) -1))]
     [number (nth hashes cnt)]))
@@ -186,8 +226,6 @@
               (recur (inc step) seed)
               [true seed])))))))
 
-(def small-primes)
-
 (with-test
 (defn generate-prime
   "Generates a cryptographically weak random prime of the given bit-length."
@@ -278,85 +316,3 @@
        119 0 -82 85 -108 -61 -92 -13 -59 89 -28 -65 -14 -33 104 68 -6 -61 2 -28
        -74 97 117 -31 77 -56 -70 -45 -50 68 40 29 47 -20 26 26 -66 -16 99 1 1 0
        0])))
-
-(def small-primes [
-  3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43,
-  47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101,
-  103, 107, 109, 113, 127, 131, 137, 139, 149, 151,
-  157, 163, 167, 173, 179, 181, 191, 193, 197, 199,
-  211, 223, 227, 229, 233, 239, 241, 251, 257, 263,
-  269, 271, 277, 281, 283, 293, 307, 311, 313, 317,
-  331, 337, 347, 349, 353, 359, 367, 373, 379, 383,
-  389, 397, 401, 409, 419, 421, 431, 433, 439, 443,
-  449, 457, 461, 463, 467, 479, 487, 491, 499, 503,
-  509, 521, 523, 541, 547, 557, 563, 569, 571, 577,
-  587, 593, 599, 601, 607, 613, 617, 619, 631, 641,
-  643, 647, 653, 659, 661, 673, 677, 683, 691, 701,
-  709, 719, 727, 733, 739, 743, 751, 757, 761, 769,
-  773, 787, 797, 809, 811, 821, 823, 827, 829, 839,
-  853, 857, 859, 863, 877, 881, 883, 887, 907, 911,
-  919, 929, 937, 941, 947, 953, 967, 971, 977, 983,
-  991, 997, 1009, 1013, 1019, 1021, 1031, 1033,
-  1039, 1049, 1051, 1061, 1063, 1069, 1087, 1091,
-  1093, 1097, 1103, 1109, 1117, 1123, 1129, 1151,
-  1153, 1163, 1171, 1181, 1187, 1193, 1201, 1213,
-  1217, 1223, 1229, 1231, 1237, 1249, 1259, 1277,
-  1279, 1283, 1289, 1291, 1297, 1301, 1303, 1307,
-  1319, 1321, 1327, 1361, 1367, 1373, 1381, 1399,
-  1409, 1423, 1427, 1429, 1433, 1439, 1447, 1451,
-  1453, 1459, 1471, 1481, 1483, 1487, 1489, 1493,
-  1499, 1511, 1523, 1531, 1543, 1549, 1553, 1559,
-  1567, 1571, 1579, 1583, 1597, 1601, 1607, 1609,
-  1613, 1619, 1621, 1627, 1637, 1657, 1663, 1667,
-  1669, 1693, 1697, 1699, 1709, 1721, 1723, 1733,
-  1741, 1747, 1753, 1759, 1777, 1783, 1787, 1789,
-  1801, 1811, 1823, 1831, 1847, 1861, 1867, 1871,
-  1873, 1877, 1879, 1889, 1901, 1907, 1913, 1931,
-  1933, 1949, 1951, 1973, 1979, 1987, 1993, 1997,
-  1999, 2003, 2011, 2017, 2027, 2029, 2039, 2053,
-  2063, 2069, 2081, 2083, 2087, 2089, 2099, 2111,
-  2113, 2129, 2131, 2137, 2141, 2143, 2153, 2161,
-  2179, 2203, 2207, 2213, 2221, 2237, 2239, 2243,
-  2251, 2267, 2269, 2273, 2281, 2287, 2293, 2297,
-  2309, 2311, 2333, 2339, 2341, 2347, 2351, 2357,
-  2371, 2377, 2381, 2383, 2389, 2393, 2399, 2411,
-  2417, 2423, 2437, 2441, 2447, 2459, 2467, 2473,
-  2477, 2503, 2521, 2531, 2539, 2543, 2549, 2551,
-  2557, 2579, 2591, 2593, 2609, 2617, 2621, 2633,
-  2647, 2657, 2659, 2663, 2671, 2677, 2683, 2687,
-  2689, 2693, 2699, 2707, 2711, 2713, 2719, 2729,
-  2731, 2741, 2749, 2753, 2767, 2777, 2789, 2791,
-  2797, 2801, 2803, 2819, 2833, 2837, 2843, 2851,
-  2857, 2861, 2879, 2887, 2897, 2903, 2909, 2917,
-  2927, 2939, 2953, 2957, 2963, 2969, 2971, 2999,
-  3001, 3011, 3019, 3023, 3037, 3041, 3049, 3061,
-  3067, 3079, 3083, 3089, 3109, 3119, 3121, 3137,
-  3163, 3167, 3169, 3181, 3187, 3191, 3203, 3209,
-  3217, 3221, 3229, 3251, 3253, 3257, 3259, 3271,
-  3299, 3301, 3307, 3313, 3319, 3323, 3329, 3331,
-  3343, 3347, 3359, 3361, 3371, 3373, 3389, 3391,
-  3407, 3413, 3433, 3449, 3457, 3461, 3463, 3467,
-  3469, 3491, 3499, 3511, 3517, 3527, 3529, 3533,
-  3539, 3541, 3547, 3557, 3559, 3571, 3581, 3583,
-  3593, 3607, 3613, 3617, 3623, 3631, 3637, 3643,
-  3659, 3671, 3673, 3677, 3691, 3697, 3701, 3709,
-  3719, 3727, 3733, 3739, 3761, 3767, 3769, 3779,
-  3793, 3797, 3803, 3821, 3823, 3833, 3847, 3851,
-  3853, 3863, 3877, 3881, 3889, 3907, 3911, 3917,
-  3919, 3923, 3929, 3931, 3943, 3947, 3967, 3989,
-  4001, 4003, 4007, 4013, 4019, 4021, 4027, 4049,
-  4051, 4057, 4073, 4079, 4091, 4093, 4099, 4111,
-  4127, 4129, 4133, 4139, 4153, 4157, 4159, 4177,
-  4201, 4211, 4217, 4219, 4229, 4231, 4241, 4243,
-  4253, 4259, 4261, 4271, 4273, 4283, 4289, 4297,
-  4327, 4337, 4339, 4349, 4357, 4363, 4373, 4391,
-  4397, 4409, 4421, 4423, 4441, 4447, 4451, 4457,
-  4463, 4481, 4483, 4493, 4507, 4513, 4517, 4519,
-  4523, 4547, 4549, 4561, 4567, 4583, 4591, 4597,
-  4603, 4621, 4637, 4639, 4643, 4649, 4651, 4657,
-  4663, 4673, 4679, 4691, 4703, 4721, 4723, 4729,
-  4733, 4751, 4759, 4783, 4787, 4789, 4793, 4799,
-  4801, 4813, 4817, 4831, 4861, 4871, 4877, 4889,
-  4903, 4909, 4919, 4931, 4933, 4937, 4943, 4951,
-  4957, 4967, 4969, 4973, 4987, 4993, 4999,
-  ])
diff --git a/src/org/gnu/clojure/gnunet/primes.clj b/src/org/gnu/clojure/gnunet/primes.clj
new file mode 100644
index 0000000..1c143b4
--- /dev/null
+++ b/src/org/gnu/clojure/gnunet/primes.clj
@@ -0,0 +1,83 @@
+(ns org.gnu.clojure.gnunet.primes)
+
+(def small-primes [
+  3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43,
+  47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101,
+  103, 107, 109, 113, 127, 131, 137, 139, 149, 151,
+  157, 163, 167, 173, 179, 181, 191, 193, 197, 199,
+  211, 223, 227, 229, 233, 239, 241, 251, 257, 263,
+  269, 271, 277, 281, 283, 293, 307, 311, 313, 317,
+  331, 337, 347, 349, 353, 359, 367, 373, 379, 383,
+  389, 397, 401, 409, 419, 421, 431, 433, 439, 443,
+  449, 457, 461, 463, 467, 479, 487, 491, 499, 503,
+  509, 521, 523, 541, 547, 557, 563, 569, 571, 577,
+  587, 593, 599, 601, 607, 613, 617, 619, 631, 641,
+  643, 647, 653, 659, 661, 673, 677, 683, 691, 701,
+  709, 719, 727, 733, 739, 743, 751, 757, 761, 769,
+  773, 787, 797, 809, 811, 821, 823, 827, 829, 839,
+  853, 857, 859, 863, 877, 881, 883, 887, 907, 911,
+  919, 929, 937, 941, 947, 953, 967, 971, 977, 983,
+  991, 997, 1009, 1013, 1019, 1021, 1031, 1033,
+  1039, 1049, 1051, 1061, 1063, 1069, 1087, 1091,
+  1093, 1097, 1103, 1109, 1117, 1123, 1129, 1151,
+  1153, 1163, 1171, 1181, 1187, 1193, 1201, 1213,
+  1217, 1223, 1229, 1231, 1237, 1249, 1259, 1277,
+  1279, 1283, 1289, 1291, 1297, 1301, 1303, 1307,
+  1319, 1321, 1327, 1361, 1367, 1373, 1381, 1399,
+  1409, 1423, 1427, 1429, 1433, 1439, 1447, 1451,
+  1453, 1459, 1471, 1481, 1483, 1487, 1489, 1493,
+  1499, 1511, 1523, 1531, 1543, 1549, 1553, 1559,
+  1567, 1571, 1579, 1583, 1597, 1601, 1607, 1609,
+  1613, 1619, 1621, 1627, 1637, 1657, 1663, 1667,
+  1669, 1693, 1697, 1699, 1709, 1721, 1723, 1733,
+  1741, 1747, 1753, 1759, 1777, 1783, 1787, 1789,
+  1801, 1811, 1823, 1831, 1847, 1861, 1867, 1871,
+  1873, 1877, 1879, 1889, 1901, 1907, 1913, 1931,
+  1933, 1949, 1951, 1973, 1979, 1987, 1993, 1997,
+  1999, 2003, 2011, 2017, 2027, 2029, 2039, 2053,
+  2063, 2069, 2081, 2083, 2087, 2089, 2099, 2111,
+  2113, 2129, 2131, 2137, 2141, 2143, 2153, 2161,
+  2179, 2203, 2207, 2213, 2221, 2237, 2239, 2243,
+  2251, 2267, 2269, 2273, 2281, 2287, 2293, 2297,
+  2309, 2311, 2333, 2339, 2341, 2347, 2351, 2357,
+  2371, 2377, 2381, 2383, 2389, 2393, 2399, 2411,
+  2417, 2423, 2437, 2441, 2447, 2459, 2467, 2473,
+  2477, 2503, 2521, 2531, 2539, 2543, 2549, 2551,
+  2557, 2579, 2591, 2593, 2609, 2617, 2621, 2633,
+  2647, 2657, 2659, 2663, 2671, 2677, 2683, 2687,
+  2689, 2693, 2699, 2707, 2711, 2713, 2719, 2729,
+  2731, 2741, 2749, 2753, 2767, 2777, 2789, 2791,
+  2797, 2801, 2803, 2819, 2833, 2837, 2843, 2851,
+  2857, 2861, 2879, 2887, 2897, 2903, 2909, 2917,
+  2927, 2939, 2953, 2957, 2963, 2969, 2971, 2999,
+  3001, 3011, 3019, 3023, 3037, 3041, 3049, 3061,
+  3067, 3079, 3083, 3089, 3109, 3119, 3121, 3137,
+  3163, 3167, 3169, 3181, 3187, 3191, 3203, 3209,
+  3217, 3221, 3229, 3251, 3253, 3257, 3259, 3271,
+  3299, 3301, 3307, 3313, 3319, 3323, 3329, 3331,
+  3343, 3347, 3359, 3361, 3371, 3373, 3389, 3391,
+  3407, 3413, 3433, 3449, 3457, 3461, 3463, 3467,
+  3469, 3491, 3499, 3511, 3517, 3527, 3529, 3533,
+  3539, 3541, 3547, 3557, 3559, 3571, 3581, 3583,
+  3593, 3607, 3613, 3617, 3623, 3631, 3637, 3643,
+  3659, 3671, 3673, 3677, 3691, 3697, 3701, 3709,
+  3719, 3727, 3733, 3739, 3761, 3767, 3769, 3779,
+  3793, 3797, 3803, 3821, 3823, 3833, 3847, 3851,
+  3853, 3863, 3877, 3881, 3889, 3907, 3911, 3917,
+  3919, 3923, 3929, 3931, 3943, 3947, 3967, 3989,
+  4001, 4003, 4007, 4013, 4019, 4021, 4027, 4049,
+  4051, 4057, 4073, 4079, 4091, 4093, 4099, 4111,
+  4127, 4129, 4133, 4139, 4153, 4157, 4159, 4177,
+  4201, 4211, 4217, 4219, 4229, 4231, 4241, 4243,
+  4253, 4259, 4261, 4271, 4273, 4283, 4289, 4297,
+  4327, 4337, 4339, 4349, 4357, 4363, 4373, 4391,
+  4397, 4409, 4421, 4423, 4441, 4447, 4451, 4457,
+  4463, 4481, 4483, 4493, 4507, 4513, 4517, 4519,
+  4523, 4547, 4549, 4561, 4567, 4583, 4591, 4597,
+  4603, 4621, 4637, 4639, 4643, 4649, 4651, 4657,
+  4663, 4673, 4679, 4691, 4703, 4721, 4723, 4729,
+  4733, 4751, 4759, 4783, 4787, 4789, 4793, 4799,
+  4801, 4813, 4817, 4831, 4861, 4871, 4877, 4889,
+  4903, 4909, 4919, 4931, 4933, 4937, 4943, 4951,
+  4957, 4967, 4969, 4973, 4987, 4993, 4999,
+  ])