New hash variant SHA224.

[u/mdw/catacomb] / sha256.c

diff --git a/sha256.c b/sha256.c
index 54a4c85..8ffc689 100644 (file)
--- a/sha256.c
+++ b/sha256.c
@@ -1,6 +1,6 @@
 /* -*-c-*-
  *
- * $Id: sha256.c,v 1.1 2000/10/15 17:48:14 mdw Exp $
+ * $Id: sha256.c,v 1.2 2004/03/21 22:43:34 mdw Exp $
  *
  * Implementation of the SHA-256 hash function
  *
@@ -30,6 +30,9 @@
 /*----- Revision history --------------------------------------------------* 
  *
  * $Log: sha256.c,v $
+ * Revision 1.2  2004/03/21 22:43:34  mdw
+ * New hash variant SHA224.
+ *
  * Revision 1.1  2000/10/15 17:48:14  mdw
  * New SHA variants with longer outputs.
  *
@@ -46,7 +49,7 @@
 
 /*----- Main code ---------------------------------------------------------*/
 
-/* --- @sha256_compress@ --- *
+/* --- @sha256_compress@, @sha224_compress@ --- *
  *
  * Arguments:  @sha256_ctx *ctx@ = pointer to context block
  *             @const void *sbuf@ = pointer to buffer of appropriate size
@@ -179,7 +182,7 @@ void sha256_compress(sha256_ctx *ctx, const void *sbuf)
   ctx->h += h;
 }
 
-/* --- @sha256_init@ --- *
+/* --- @sha256_init@, @sha224_init@ --- *
  *
  * Arguments:  @sha256_ctx *ctx@ = pointer to context block to initialize
  *
@@ -202,7 +205,21 @@ void sha256_init(sha256_ctx *ctx)
   ctx->nl = ctx->nh = 0;
 }
 
-/* --- @sha256_set@ --- *
+void sha224_init(sha256_ctx *ctx)
+{
+  ctx->a = 0xc1059ed8;
+  ctx->b = 0x367cd507;
+  ctx->c = 0x3070dd17;
+  ctx->d = 0xf70e5939;
+  ctx->e = 0xffc00b31;
+  ctx->f = 0x68581511;
+  ctx->g = 0x64f98fa7;
+  ctx->h = 0xbefa4fa4;
+  ctx->off = 0;
+  ctx->nl = ctx->nh = 0;
+}
+
+/* --- @sha256_set@, @sha224_set@ --- *
  *
  * Arguments:  @sha256_ctx *ctx@ = pointer to context block
  *             @const void *buf@ = pointer to state buffer
@@ -231,7 +248,7 @@ void sha256_set(sha256_ctx *ctx, const void *buf, unsigned long count)
   ctx->nh = U32(((count & ~MASK32) >> 16) >> 16);
 }
 
-/* --- @sha256_hash@ --- *
+/* --- @sha256_hash@, @sha224_hash@ --- *
  *
  * Arguments:  @sha256_ctx *ctx@ = pointer to context block
  *             @const void *buf@ = buffer of data to hash
@@ -248,7 +265,7 @@ void sha256_hash(sha256_ctx *ctx, const void *buf, size_t sz)
   HASH_BUFFER(SHA256, sha256, ctx, buf, sz);
 }
 
-/* --- @sha256_done@ --- *
+/* --- @sha256_done, @sha224_done@ --- *
  *
  * Arguments:  @sha256_ctx *ctx@ = pointer to context block
  *             @void *hash@ = pointer to output buffer
@@ -258,13 +275,18 @@ void sha256_hash(sha256_ctx *ctx, const void *buf, size_t sz)
  * Use:                Returns the hash of the data read so far.
  */
 
-void sha256_done(sha256_ctx *ctx, void *hash)
+static void final(sha256_ctx *ctx)
 {
-  octet *p = hash;
   HASH_PAD(SHA256, sha256, ctx, 0x80, 0, 8);
   STORE32(ctx->buf + SHA256_BUFSZ - 8, (ctx->nl >> 29) | (ctx->nh << 3));
   STORE32(ctx->buf + SHA256_BUFSZ - 4, ctx->nl << 3);
-  sha256_compress(ctx, ctx->buf);
+  sha256_compress(ctx, ctx->buf);  
+}
+
+void sha256_done(sha256_ctx *ctx, void *hash)
+{
+  octet *p = hash;
+  final(ctx);
   STORE32(p +  0, ctx->a);
   STORE32(p +  4, ctx->b);
   STORE32(p +  8, ctx->c);
@@ -275,7 +297,20 @@ void sha256_done(sha256_ctx *ctx, void *hash)
   STORE32(p + 28, ctx->h);
 }
 
-/* --- @sha256_state@ --- *
+void sha224_done(sha224_ctx *ctx, void *hash)
+{
+  octet *p = hash;
+  final(ctx);
+  STORE32(p +  0, ctx->a);
+  STORE32(p +  4, ctx->b);
+  STORE32(p +  8, ctx->c);
+  STORE32(p + 12, ctx->d);
+  STORE32(p + 16, ctx->e);
+  STORE32(p + 20, ctx->f);
+  STORE32(p + 24, ctx->g);
+}
+
+/* --- @sha256_state@, @sha224_state@ --- *
  *
  * Arguments:  @sha256_ctx *ctx@ = pointer to context
  *             @void *state@ = pointer to buffer for current state