--- /dev/null
+/* -*-c-*-
+ *
+ * The MD2 message digest function
+ *
+ * (c) 2001 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of Catacomb.
+ *
+ * Catacomb is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * Catacomb is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with Catacomb; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <mLib/bits.h>
+
+#include "ghash.h"
+#include "ghash-def.h"
+#include "hash.h"
+#include "md2.h"
+#include "md2-tab.h"
+
+/*----- Tables ------------------------------------------------------------*/
+
+static const octet s[256] = MD2_S;
+
+/*----- Main code ---------------------------------------------------------*/
+
+/* --- @md2_compress@ --- *
+ *
+ * Arguments: @md2_ctx *ctx@ = pointer to context block
+ * @const void *sbuf@ = pointer to buffer of appropriate size
+ *
+ * Returns: ---
+ *
+ * Use: MD2 compression and checksum function.
+ */
+
+void md2_compress(md2_ctx *ctx, const void *sbuf)
+{
+ unsigned i;
+ unsigned t;
+ octet x[MD2_BUFSZ];
+ octet y[MD2_BUFSZ];
+
+ /* --- Handy macro for doing something lots of times --- */
+
+#define DO(what, where) do { \
+ what(where, 0); what(where, 1); what(where, 2); what(where, 3); \
+ what(where, 4); what(where, 5); what(where, 6); what(where, 7); \
+ what(where, 8); what(where, 9); what(where, 10); what(where, 11); \
+ what(where, 12); what(where, 13); what(where, 14); what(where, 15); \
+} while (0)
+
+ /* --- Do the hashing first to avoid corrupting the checksum --- */
+
+ memcpy(x, sbuf, sizeof(x));
+#define X(z, i) y[i] = z[i] ^ ctx->h[i]
+ DO(X, x);
+#undef X
+
+ t = 0;
+ for (i = 0; i < 18; i++) {
+#define X(z, i) t = z[i] ^= s[t];
+ DO(X, ctx->h);
+ DO(X, x);
+ DO(X, y);
+#undef X
+ t = U8(t + i);
+ }
+
+ /* --- Now compute the checksum --- */
+
+ t = ctx->c[MD2_BUFSZ - 1];
+#define X(z, i) t = ctx->c[i] ^= s[z[i] ^ t]
+ DO(X, ((const octet *)sbuf));
+#undef X
+
+#undef DO
+}
+
+/* --- @md2_init@ --- *
+ *
+ * Arguments: @md2_ctx *ctx@ = pointer to context block to initialize
+ *
+ * Returns: ---
+ *
+ * Use: Initializes a context block ready for hashing.
+ */
+
+void md2_init(md2_ctx *ctx)
+{
+ memset(ctx->c, 0, sizeof(ctx->c));
+ memset(ctx->h, 0, sizeof(ctx->h));
+ ctx->off = 0;
+}
+
+/* --- @md2_set@ --- *
+ *
+ * Arguments: @md2_ctx *ctx@ = pointer to context block
+ * @const void *buf@ = pointer to state buffer
+ * @unsigned long count@ = current count of bytes processed
+ *
+ * Returns: ---
+ *
+ * Use: Initializes a context block from a given state. This is
+ * useful in cases where the initial hash state is meant to be
+ * secret, e.g., for NMAC and HMAC support.
+ */
+
+void md2_set(md2_ctx *ctx, const void *buf, unsigned long count)
+{
+ const octet *p = buf;
+ memcpy(ctx->h, p, MD2_BUFSZ);
+ memcpy(ctx->c, p + MD2_BUFSZ, MD2_BUFSZ);
+ ctx->off = 0;
+}
+
+/* --- @md2_hash@ --- *
+ *
+ * Arguments: @md2_ctx *ctx@ = pointer to context block
+ * @const void *buf@ = buffer of data to hash
+ * @size_t sz@ = size of buffer to hash
+ *
+ * Returns: ---
+ *
+ * Use: Hashes a buffer of data. The buffer may be of any size and
+ * alignment.
+ */
+
+void md2_hash(md2_ctx *ctx, const void *buf, size_t sz)
+{
+ const octet *bbuf = (octet *)buf;
+
+ /* --- Code automatically expanded from @HASH_BUFFER@ and tidied --- */
+
+ if (ctx->off + sz < MD2_BUFSZ) {
+ memcpy(ctx->buf + ctx->off, bbuf, sz);
+ ctx->off += sz;
+ } else {
+ if (ctx->off) {
+ size_t s = MD2_BUFSZ - ctx->off;
+ memcpy(ctx->buf + ctx->off, bbuf, s);
+ md2_compress(ctx, ctx->buf);
+ sz -= s;
+ bbuf += s;
+ }
+ while (sz >= MD2_BUFSZ) {
+ md2_compress(ctx, bbuf);
+ sz -= MD2_BUFSZ; bbuf += MD2_BUFSZ;
+ }
+ if (sz)
+ memcpy(ctx->buf, bbuf, sz);
+ ctx->off = sz;
+ }
+}
+
+/* --- @md2_done@ --- *
+ *
+ * Arguments: @md2_ctx *ctx@ = pointer to context block
+ * @void *hash@ = pointer to output buffer
+ *
+ * Returns: ---
+ *
+ * Use: Returns the hash of the data read so far.
+ */
+
+void md2_done(md2_ctx *ctx, void *hash)
+{
+ unsigned pad = MD2_BUFSZ - ctx->off;
+ unsigned i;
+ for (i = ctx->off; i < MD2_BUFSZ; i++)
+ ctx->buf[i] = pad;
+ md2_compress(ctx, ctx->buf);
+ md2_compress(ctx, ctx->c);
+ memcpy(hash, ctx->h, MD2_BUFSZ);
+}
+
+/* --- @md2_state@ --- *
+ *
+ * Arguments: @md2_ctx *ctx@ = pointer to context
+ * @void *state@ = pointer to buffer for current state
+ *
+ * Returns: Number of bytes written to the hash function so far.
+ *
+ * Use: Returns the current state of the hash function such that
+ * it can be passed to @md2_set@.
+ */
+
+unsigned long md2_state(md2_ctx *ctx, void *state)
+{
+ octet *p = state;
+ memcpy(p, ctx->h, MD2_BUFSZ);
+ memcpy(p + MD2_BUFSZ, ctx->c, MD2_BUFSZ);
+ return (0);
+}
+
+/* --- Generic interface --- */
+
+GHASH_DEF(MD2, md2)
+
+/* --- Test code --- */
+
+HASH_TEST(MD2, md2)
+
+/*----- That's all, folks -------------------------------------------------*/
projects / u / mdw / catacomb / blobdiff