final fixes to 429-6 HMAC

1 files changed, 5 insertions, 70 deletions

diff --git a/src/AS_DCP_AES.cpp b/src/AS_DCP_AES.cpp
index 037e68d..1146bb7 100755
--- a/src/AS_DCP_AES.cpp
+++ b/src/AS_DCP_AES.cpp
@@ -1,5 +1,5 @@
 /*
-Copyright (c) 2004-2006, John Hurst
+Copyright (c) 2004-2007, John Hurst
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
@@ -33,6 +33,7 @@ THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <assert.h>
 #include <AS_DCP.h>
 #include <KM_log.h>
+#include <KM_prng.h>
 using Kumu::DefaultLogSink;
 
 using namespace ASDCP;
@@ -43,14 +44,6 @@ const int KEY_SIZE_BITS = 128;
 #include <openssl/bn.h>
 #include <openssl/err.h>
 
-#if OPENSSL_VERSION_NUMBER < 0x0090804f
-# error OpenSSL version mismatch
-#endif
-
-#ifndef OPENSSL_VERSION_NUMBER
-#error OPENSSL_VERSION_NUMBER not defined
-#endif
-
 
 void
 print_ssl_error()
@@ -269,67 +262,9 @@ public:
   // SMPTE 429.6 MIC key generation
   void SetKey(const byte_t* key)
   {
-    // FIPS 186-2 Sec. 3.1 as modified by Change 1, section entitled "General Purpose Random Number Generation"
-    //
-
-    static byte_t t[SHA_DIGEST_LENGTH] = {
-      0x67, 0x45, 0x23, 0x01, 0xef, 0xcd, 0xab, 0x89,
-      0x98, 0xba, 0xdc, 0xfe, 0x10, 0x32, 0x54, 0x76,
-      0xc3, 0xd2, 0xe1, 0xf0
-    };
-
-    byte_t sha_buf0[SHA_DIGEST_LENGTH];
-    byte_t sha_buf1[SHA_DIGEST_LENGTH];
-    SHA_CTX SHA;
-    BN_CTX* ctx1 = BN_CTX_new(); // used by BN_* functions
-    assert(ctx1);
-
-    // create the 2^160 constant
-    BIGNUM c_2powb, c_2, c_160;
-    BN_init(&c_2powb);  BN_init(&c_2);  BN_init(&c_160);
-    BN_set_word(&c_2, 2);
-    BN_set_word(&c_160, 160);
-    BN_exp(&c_2powb, &c_2, &c_160, ctx1);
-
-    // ROUND 1
-    // step a -- SMPTE 429.6 sets XSEED = 0, so no need to do anything for this step
-    // step b -- (key mod 2^160) is moot because the input value is only 128 bits in length
-
-    // step c -- x = G(t,xkey)
-    SHA1_Init(&SHA);
-    SHA1_Update(&SHA, t, SHA_DIGEST_LENGTH);
-    SHA1_Update(&SHA, key, KeyLen);
-    SHA1_Final(sha_buf0, &SHA);
-
-    // step d ...
-    BIGNUM xkey1, xkey2, x0;
-    BN_init(&xkey1);  BN_init(&xkey2);    BN_init(&x0);
-
-    BN_bin2bn(key, KeyLen, &xkey1);
-    BN_bin2bn(sha_buf0, SHA_DIGEST_LENGTH, &x0);
-    BN_add_word(&xkey1, 1);            // xkey += 1
-    BN_add(&xkey2, &xkey1, &x0);       // xkey += x
-    BN_mod(&xkey1, &xkey2, &c_2powb, ctx1);  // xkey = xkey mod (2^160)
-
-    // ROUND 2
-    // step a -- SMPTE 429.6 sets XSEED = 0, so no need to do anything for this step
-    // step b -- (key mod 2^160) is moot because xkey1 is the result of the same operation
-
-    byte_t bin_buf[SHA_DIGEST_LENGTH+1]; // we need xkey1 in bin form for use by SHA1_Update
-    ui32_t bin_buf_len = BN_num_bytes(&xkey1);
-    assert(bin_buf_len < SHA_DIGEST_LENGTH+1);
-    BN_bn2bin(&xkey1, bin_buf);
-
-    // step c -- x = G(t,xkey)
-    SHA1_Init(&SHA);
-    SHA1_Update(&SHA, t, SHA_DIGEST_LENGTH);
-    SHA1_Update(&SHA, bin_buf, bin_buf_len);
-    SHA1_Final(sha_buf1, &SHA);
-
-    assert(memcmp(sha_buf1, sha_buf0, SHA_DIGEST_LENGTH) != 0); // are x0 and x1 different?
-
-    BN_CTX_free(ctx1);
-    memcpy(m_key, sha_buf1, KeyLen);
+    byte_t rng_buf[SHA_DIGEST_LENGTH*2];
+    Kumu::Gen_FIPS_186_Value(key, KeyLen, rng_buf, SHA_DIGEST_LENGTH*2);
+    memcpy(m_key, rng_buf+SHA_DIGEST_LENGTH, KeyLen);
     Reset();
   }