m gitignore + implementation of squeezers

Signed-off-by: Mattias Andrée <maandree@operamail.com>

2 files changed, 116 insertions, 4 deletions

diff --git a/src/libkeccak/digest.c b/src/libkeccak/digest.c
new file mode 100644
index 0000000..b6fd215
--- /dev/null
+++ b/src/libkeccak/digest.c
@@ -0,0 +1,113 @@
+/**
+ * libkeccak – Keccak-family hashing library
+ * 
+ * Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program 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 Affero General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "digest.h"
+
+
+/**
+ * Absorb the more of the message to the Keccak sponge
+ * 
+ * @param  state   The hashing state
+ * @param  msg     The partial message
+ * @param  msglen  The length of the partial message
+ */
+void libkeccak_update(libkeccak_state_t* restrict state, const char* restrict msg, size_t msglen)
+{
+}
+
+
+/**
+ * Absorb the last part of the message and squeeze the Keccak sponge
+ * 
+ * @param   state    The hashing state
+ * @param   msg      The rest of the message, may be `NULL`
+ * @param   msglen   The length of the partial message
+ * @param   bits     The number of bits at the end of the message not covered by `msglen`
+ * @param   suffix   The suffix concatenate to the message
+ * @param   hashsum  Output paramter for the hashsum, may be `NULL`
+ * @return           Zero on success, -1 on error
+ */
+int libkeccak_digest(libkeccak_state_t* restrict state, const char* restrict msg, size_t msglen,
+		     size_t bits, const char* restrict suffix, char* restrict hashsum)
+{
+}
+
+
+/**
+ * Force some rounds of Keccak-f
+ * 
+ * @param  state  The hashing state
+ * @param  times  The number of rounds
+ */
+void libkeccak_simple_squeeze(libkeccak_state_t* restrict state, long times)
+{
+  while (times--)
+    libkeccak_f(state);
+}
+
+
+/**
+ * Squeeze as much as is needed to get a digest a number of times
+ * 
+ * @param  state  The hashing state
+ * @param  times  The number of digests
+ */
+void libkeccak_fast_squeeze(libkeccak_state_t* restrict state, long times)
+{
+  times *= (state->n - 1) / state->r + 1;
+  while (times--)
+    libkeccak_f(state);
+}
+
+
+/**
+ * Squeeze out another digest
+ * 
+ * @param  state    The hashing state
+ * @param  hashsum  Output paramter for the hashsum
+ */
+void libkeccak_squeeze(libkeccak_state_t* restrict state, char* restrict hashsum)
+{
+  long ww, nn, olen, i, j, k, ptr, rr, ni;
+  int_fast64_t v;
+  
+  libkeccak_f(state);
+  
+  ww = state->w >> 3;
+  nn = (state->n + 7) >> 3;
+  olen = state->n;
+  j = ptr = 0;
+  rr = state->r >> 3;
+  ni = rr > 25 ? 25 : rr;
+  
+  while (olen > 0)
+    {
+      for (i = 0; (i < ni) && (j < nn); i++)
+	{
+	  v = state->S[(i % 5) * 5 + i / 5];
+	  for (k = 0; k++ < ww; v >>= 8)
+	    if (j++ < nn)
+	      hashsum[ptr++] = (char)v;
+	}
+      if (olen -= state->r, olen > 0)
+	libkeccak_f(state);
+    }
+  if (n & 7)
+    n[nn - 1] &= (1 << (n & 7)) - 1;
+}
+
diff --git a/src/libkeccak/digest.h b/src/libkeccak/digest.h
index 4853631..fcd3d50 100644
--- a/src/libkeccak/digest.h
+++ b/src/libkeccak/digest.h
@@ -73,12 +73,11 @@ void libkeccak_fast_squeeze(libkeccak_state_t* restrict state, long times);
 /**
  * Squeeze out another digest
  * 
- * @param   state    The hashing state
- * @param   hashsum  Output paramter for the hashsum
- * @return           Zero on success, -1 on error
+ * @param  state    The hashing state
+ * @param  hashsum  Output paramter for the hashsum
  */
 __attribute__((nonnull, nothrow))
-int libkeccak_squeeze(libkeccak_state_t* restrict state, char* restrict hashsum);
+void libkeccak_squeeze(libkeccak_state_t* restrict state, char* restrict hashsum);
 
 
 #undef