Merge pull request #34 from pjbgf/generic-opts

go: Refactor for clarity and performance

Author: pjbgf

.github/workflows/build.yml

@@ -18,7 +18,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        go-version: [1.19.x]
+        go-version: [1.20.x]
         platform: [ubuntu-latest]
 
     runs-on: ${{ matrix.platform }}

.github/workflows/nightly.yml

@@ -18,7 +18,7 @@ jobs:
       - name: Setup Go
         uses: actions/setup-go@6edd4406fa81c3da01a34fa6f6343087c207a568 # v3.5.0
         with:
-          go-version: 1.19.x
+          go-version: 1.20.x
       - name: Run fuzzers
         env:
           FUZZ_TIME: 30m

.github/workflows/tests.yml

@@ -21,7 +21,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        go-version: [1.15.x, 1.16.x, 1.17.x, 1.18.x, 1.19.x]
+        go-version: [1.16.x, 1.17.x, 1.18.x, 1.19.x, 1.20.x]
         platform: [ubuntu-latest, macos-latest, windows-latest]
 
     runs-on: ${{ matrix.platform }}
@@ -43,7 +43,7 @@ jobs:
       - name: Setup Go
         uses: actions/setup-go@6edd4406fa81c3da01a34fa6f6343087c207a568 # v3.5.0
         with:
-          go-version: 1.19.x
+          go-version: 1.20.x
       - name: Run benchmarks
         run: make bench
       - name: Run fuzzers

internal/const.go

@@ -0,0 +1,38 @@
+package shared
+
+const (
+	// Constants for the SHA-1 hash function.
+	K0 = 0x5A827999
+	K1 = 0x6ED9EBA1
+	K2 = 0x8F1BBCDC
+	K3 = 0xCA62C1D6
+
+	// Initial values for the buffer variables: h0, h1, h2, h3, h4.
+	Init0 = 0x67452301
+	Init1 = 0xEFCDAB89
+	Init2 = 0x98BADCFE
+	Init3 = 0x10325476
+	Init4 = 0xC3D2E1F0
+
+	// Initial values for the temporary variables (ihvtmp0, ihvtmp1, ihvtmp2, ihvtmp3, ihvtmp4) during the SHA recompression step.
+	InitTmp0 = 0xD5
+	InitTmp1 = 0x394
+	InitTmp2 = 0x8152A8
+	InitTmp3 = 0x0
+	InitTmp4 = 0xA7ECE0
+
+	// SHA1 contains 2 buffers, each based off 5 32-bit words.
+	WordBuffers = 5
+
+	// The output of SHA1 is 20 bytes (160 bits).
+	Size = 20
+
+	// Rounds represents the number of steps required to process each chunk.
+	Rounds = 80
+
+	// SHA1 processes the input data in chunks. Each chunk contains 64 bytes.
+	Chunk = 64
+
+	Magic         = "shacd\x01"
+	MarshaledSize = len(Magic) + 5*4 + Chunk + 8
+)