[libdmapsharing] Add progressive MD5 hash function

[W. Michael Petullo <wmpetullo src gnome org>]

commit 2a4009b2e16444b73ba03fe82453cc4630f77b66
Author: W. Michael Petullo <mike flyn org>
Date:   Wed Jul 17 23:04:18 2013 -0400

    Add progressive MD5 hash function
    
    Signed-off-by: W. Michael Petullo <mike flyn org>

 libdmapsharing/dmap-md5.c |   90 +++++++++++++++++++++++++++++++++++++-------
 libdmapsharing/dmap-md5.h |   27 +++++++++++--
 tests/unit-test.c         |    4 +-
 3 files changed, 101 insertions(+), 20 deletions(-)
---
diff --git a/libdmapsharing/dmap-md5.c b/libdmapsharing/dmap-md5.c
index 020d8c9..460994a 100644
--- a/libdmapsharing/dmap-md5.c
+++ b/libdmapsharing/dmap-md5.c
@@ -31,14 +31,6 @@
  * Copyright (c) 2004 David Hammerton
  */
 
-typedef struct
-{
-       guint32 buf[4];
-       guint32 bits[2];
-       unsigned char in[64];
-       gint version;
-} MD5_CTX;
-
 /*
  * This code implements the MD5 message-digest algorithm.
  * The algorithm is due to Ron Rivest.  This code was
@@ -86,9 +78,9 @@ byteReverse (unsigned char *buf, unsigned longs)
 #endif /* #if 0 */
 
 static void
-DMAP_MD5Init (MD5_CTX * ctx, gint version)
+DMAP_MD5Init (DMAPHashContext * ctx, gint version)
 {
-       memset (ctx, 0, sizeof (MD5_CTX));
+       memset (ctx, 0, sizeof (DMAPHashContext));
        ctx->buf[0] = 0x67452301;
        ctx->buf[1] = 0xefcdab89;
        ctx->buf[2] = 0x98badcfe;
@@ -101,7 +93,7 @@ DMAP_MD5Init (MD5_CTX * ctx, gint version)
 }
 
 static void
-DMAP_MD5Update (MD5_CTX * ctx, unsigned char const *buf, unsigned int len)
+DMAP_MD5Update (DMAPHashContext * ctx, unsigned char const *buf, unsigned int len)
 {
        guint32 t;
 
@@ -146,7 +138,7 @@ DMAP_MD5Update (MD5_CTX * ctx, unsigned char const *buf, unsigned int len)
 }
 
 static void
-DMAP_MD5Final (MD5_CTX * ctx, unsigned char digest[16])
+DMAP_MD5Final (DMAPHashContext * ctx, unsigned char digest[16])
 {
        unsigned count;
        unsigned char *p;
@@ -324,7 +316,7 @@ DigestToString (const unsigned char *digest, gchar * string)
 static void
 GenerateStatic_42 ()
 {
-       MD5_CTX ctx;
+       DMAPHashContext ctx;
        unsigned char *p = staticHash_42;
        int i;
        unsigned char buf[16];
@@ -384,7 +376,7 @@ GenerateStatic_42 ()
 static void
 GenerateStatic_45 ()
 {
-       MD5_CTX ctx;
+       DMAPHashContext ctx;
        unsigned char *p = staticHash_45;
        int i;
        unsigned char buf[16];
@@ -448,7 +440,7 @@ dmap_hash_generate (short version_major,
                    guchar hash_select, guchar * out, gint request_id)
 {
        unsigned char buf[16];
-       MD5_CTX ctx;
+       DMAPHashContext ctx;
        gint i;
 
        unsigned char *hashTable = (version_major == 3) ?
@@ -469,6 +461,7 @@ dmap_hash_generate (short version_major,
                }
                ac_unfudged = TRUE;
        }
+
        DMAP_MD5Update (&ctx, (const guchar *) ac, strlen (ac));
 
        DMAP_MD5Update (&ctx, &hashTable[hash_select * 65], 32);
@@ -487,6 +480,50 @@ dmap_hash_generate (short version_major,
        return;
 }
 
+void dmap_hash_progressive_init (DMAPHashContext *context)
+{
+       /* FIXME: Share this stuff with dmap_hash_generate() */
+       if (!staticHashDone) {
+               GenerateStatic_42 ();
+               GenerateStatic_45 ();
+               staticHashDone = 1;
+       }
+
+       DMAP_MD5Init (context, 1);
+}
+
+void dmap_hash_progressive_update (DMAPHashContext *context,
+                                   unsigned char const *buffer,
+                                   unsigned int length)
+{
+       DMAP_MD5Update (context, buffer, length);
+}
+
+void dmap_hash_progressive_final (DMAPHashContext *context,
+                                  unsigned char digest[16])
+{
+       /* FIXME: This is only equivalent to dmap_hash_generate()
+         *        when it is called with (3, x, 2, y, 0).
+         */
+       int i;
+       unsigned char buf[16];
+
+       /* FIXME: Share this stuff with dmap_hash_generate() */
+       if (ac_unfudged == FALSE) {
+               for (i = 0; i < strlen (ac); i++) {
+                       ac[i] = ac[i] - 1;
+               }
+               ac_unfudged = TRUE;
+       }
+
+       DMAP_MD5Update (context, (const guchar *) ac, strlen (ac));
+
+       DMAP_MD5Update (context, &staticHash_45[2 * 65], 32);
+
+       DMAP_MD5Final (context, buf);
+       DigestToString (buf, (gchar *) digest);
+}
+
 #ifdef HAVE_CHECK
 START_TEST(test_dmap_hash_generate_v3_h2)
 {
@@ -497,6 +534,28 @@ START_TEST(test_dmap_hash_generate_v3_h2)
 }
 END_TEST
 
+START_TEST(test_dmap_hash_progressive)
+{
+       char hash1[33] = { 0 };
+       char hash2[33] = { 0 };
+       char *value = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+       DMAPHashContext context;
+
+       dmap_hash_progressive_init   (&context);
+       dmap_hash_progressive_update (&context, value,      5);
+       dmap_hash_progressive_update (&context, value + 5,  5);
+       dmap_hash_progressive_update (&context, value + 10, 5);
+       dmap_hash_progressive_update (&context, value + 15, 5);
+       dmap_hash_progressive_update (&context, value + 20, 5);
+       dmap_hash_progressive_update (&context, value + 25, 1);
+       dmap_hash_progressive_final  (&context, hash1);
+
+       dmap_hash_generate (3, value, 2, hash2, 0);
+
+       fail_unless (! strcmp (hash1, hash2)); 
+}
+END_TEST
+
 Suite *dmap_test_dmap_md5_suite (void)
 {
        TCase *tc;
@@ -504,6 +563,7 @@ Suite *dmap_test_dmap_md5_suite (void)
 
        tc = tcase_create("test_dmap_hash_generate_v3_h2");
        tcase_add_test(tc, test_dmap_hash_generate_v3_h2);
+       tcase_add_test(tc, test_dmap_hash_progressive);
        suite_add_tcase(s, tc);
 
        return s;
diff --git a/libdmapsharing/dmap-md5.h b/libdmapsharing/dmap-md5.h
index 8209106..a39f482 100644
--- a/libdmapsharing/dmap-md5.h
+++ b/libdmapsharing/dmap-md5.h
@@ -24,10 +24,29 @@
 #include <glib.h>
 
 G_BEGIN_DECLS
-       void dmap_hash_generate (short version_major,
-                                const guchar * url,
-                                guchar hash_select,
-                                guchar * out, gint request_id);
+
+typedef struct DMAPHashContext
+{
+        guint32 buf[4];
+        guint32 bits[2];
+        unsigned char in[64];
+        gint version;
+} DMAPHashContext;
+
+void dmap_hash_progressive_init   (DMAPHashContext *context);
+
+void dmap_hash_progressive_update (DMAPHashContext *context,
+                                   unsigned char const *buffer,
+                                   unsigned int length);
+
+void dmap_hash_progressive_final  (DMAPHashContext *context,
+                                   unsigned char digest[16]);
+
+void dmap_hash_generate           (short version_major,
+                                   const guchar *url,
+                                   guchar hash_select,
+                                   guchar *out,
+                                   gint request_id);
 
 #ifdef HAVE_CHECK
 #include <check.h>
diff --git a/tests/unit-test.c b/tests/unit-test.c
index afb1b09..5aefdc1 100644
--- a/tests/unit-test.c
+++ b/tests/unit-test.c
@@ -25,6 +25,9 @@
 #include <stdlib.h>
 #include <libdmapsharing/dmap.h>
 
+Suite *dmap_test_dmap_md5_suite (void);
+Suite *dmap_test_daap_connection_suite (void);
+
 static void
 debug_null (const char *log_domain,
             GLogLevelFlags log_level,
@@ -48,7 +51,6 @@ void run_suite (Suite *s)
 
 int main(void)
 {
-       g_type_init ();
        g_log_set_handler ("libdmapsharing", G_LOG_LEVEL_DEBUG, debug_null, NULL);
        g_log_set_handler (NULL, G_LOG_LEVEL_DEBUG, debug_null, NULL);