diff options
| author | Paul Selkirk <paul@psgd.org> | 2021-06-07 14:13:23 -0400 |
|---|---|---|
| committer | Paul Selkirk <paul@psgd.org> | 2021-06-07 14:13:23 -0400 |
| commit | 4b8d3a9da9a1d2639dd5d3adeaad55f338ead612 (patch) | |
| tree | 74e7247843ce9775216432b8c48f2a59f30c3fe4 /src/rtl/sha3.v | |
| parent | 2e38d480fa2767b2501a477766149476b0d03537 (diff) | |
Add mode bits for the various flavors of SHA-3, so that the softwaresha3_mode
driver doesn't have to know that the internal block size is actually 1600
bits. This involves having the "init" state zero-extend the block data,
and having "next" only absorb the block bits for that mode.
Diffstat (limited to 'src/rtl/sha3.v')
| -rw-r--r-- | src/rtl/sha3.v | 86 |
1 files changed, 74 insertions, 12 deletions
diff --git a/src/rtl/sha3.v b/src/rtl/sha3.v index a8b41bc..31b6465 100644 --- a/src/rtl/sha3.v +++ b/src/rtl/sha3.v @@ -44,20 +44,23 @@ `define SHA3_NUM_ROUNDS 5'd24
module sha3( input wire clk,
- input wire nreset,
- input wire w,
- input wire [ 8:2] addr,
- input wire [32-1:0] din,
+ input wire nreset,
+ input wire w,
+ input wire [ 8:2] addr,
+ input wire [32-1:0] din,
output wire [32-1:0] dout,
- input wire init,
- input wire next,
- output wire ready);
+ input wire init,
+ input wire next,
+ input wire [ 1:0] mode,
+ output wire ready);
- /* The SHA-3 algorithm really wants everything to be little-endian,
+ /*
+ * The SHA-3 algorithm really wants everything to be little-endian,
* which is at odds with everything else in our system (including the
* register interface to sha3_wrapper). Rather than trying to rewrite
- * Bernd's beautiful code, we'll just byte-swap all I/O.
+ * Bernd's beautiful code, I'll isolate it in its own little-endian
+ * universe by byte-swapping all reads and writes.
*/
reg [31:0] dout_swap;
@@ -193,10 +196,69 @@ module sha3( input wire clk, round <= round + 'd1;
- end else if (init || next) begin
+ end else if (init) begin
+
+ /*
+ * I'd like to have something concise like this,
+ * but the tools don't like it.
+
+ for (i = 0; i < blksize[mode]; i = i + 1)
+ st[i] <= st[i];
+
+ for (i < blksize[mode]; i < 25; i = i + 1)
+ st[i] <= 64'h0;
+
+ */
+
+ case (mode)
+ 0: begin
+ for (i = 0; i < 18; i = i + 1)
+ st[i] <= blk[i];
+ for (i = 18; i < 25; i = i + 1)
+ st[i] <= 64'h0;
+ end
+ 1: begin
+ for (i = 0; i < 17; i = i + 1)
+ st[i] <= blk[i];
+ for (i = 17; i < 25; i = i + 1)
+ st[i] <= 64'h0;
+ end
+ 2: begin
+ for (i = 0; i < 13; i = i + 1)
+ st[i] <= blk[i];
+ for (i = 13; i < 25; i = i + 1)
+ st[i] <= 64'h0;
+ end
+ 3: begin
+ for (i = 0; i < 9; i = i + 1)
+ st[i] <= blk[i];
+ for (i = 9; i < 25; i = i + 1)
+ st[i] <= 64'h0;
+ end
+ endcase
- for (i=0; i<25; i=i+1)
- st[i] <= init ? blk[i] : st[i] ^ blk[i]; // init has priority over next
+ round <= 'd0;
+
+ end else if (next) begin
+
+ case (mode)
+ 0: begin
+ for (i = 0; i < 18; i = i + 1)
+ st[i] <= st[i] ^ blk[i];
+ end
+ 1: begin
+ for (i = 0; i < 17; i = i + 1)
+ st[i] <= st[i] ^ blk[i];
+ end
+ 2: begin
+ for (i = 0; i < 13; i = i + 1)
+ st[i] <= st[i] ^ blk[i];
+ end
+ 3: begin
+ for (i = 0; i < 9; i = i + 1)
+ st[i] <= st[i] ^ blk[i];
+ end
+ endcase
round <= 'd0;
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