From 3831c4ca5de14b987f23a719a17ee0b5386f219d Mon Sep 17 00:00:00 2001
From: starainrt <i@b612.me>
Date: Mon, 14 Mar 2022 11:09:47 +0800
Subject: [PATCH] go mod support and crc32a support

---
 crc32a.go | 99 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 go.mod    |  5 +++
 go.sum    | 11 +++++++
 3 files changed, 115 insertions(+)
 create mode 100644 crc32a.go
 create mode 100644 go.mod
 create mode 100644 go.sum

diff --git a/crc32a.go b/crc32a.go
new file mode 100644
index 0000000..279d051
--- /dev/null
+++ b/crc32a.go
@@ -0,0 +1,99 @@
+package starcrypto
+
+import (
+	"encoding/binary"
+	"encoding/hex"
+)
+
+// CheckCRC32A calculates CRC32A (ITU I.363.5 algorithm, popularized by BZIP2) checksum.
+// This function will produce the same results as following PHP code:
+//  hexdec(hash('crc32', $data))
+func CheckCRC32A(data []byte) uint32 {
+	b := digest(data)
+
+	return binary.BigEndian.Uint32(b)
+}
+
+// CheckCRC32AHex is a convenience function that outputs CRC32A (ITU I.363.5 algorithm, popularized by BZIP2) checksum as a hex string.
+// This function will produce the same results as following PHP code:
+//  hash('crc32', $data)
+func ChecksumHex(data []byte) string {
+	b := digest(data)
+
+	return hex.EncodeToString(b)
+}
+
+// digest performs checksum calculation for each byte of provided data and returns digest in form of byte array.
+func digest(data []byte) []byte {
+	var crc uint32
+	var digest = make([]byte, 4)
+
+	crc = ^crc
+	for i := 0; i < len(data); i++ {
+		crc = (crc << 8) ^ table[(crc >> 24) ^ (uint32(data[i]) & 0xff)]
+	}
+	crc = ^crc
+
+	digest[3] = byte((crc >> 24) & 0xff)
+	digest[2] = byte((crc >> 16) & 0xff)
+	digest[1] = byte((crc >> 8) & 0xff)
+	digest[0] = byte(crc & 0xff)
+
+	return digest
+}
+
+// table is the pre-generated 0x04C11DB7 polynominal used for CRC32A.
+var table = [256]uint32{
+	0x0,
+	0x04c11db7, 0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b,
+	0x1a864db2, 0x1e475005, 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6,
+	0x2b4bcb61, 0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd,
+	0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9, 0x5f15adac,
+	0x5bd4b01b, 0x569796c2, 0x52568b75, 0x6a1936c8, 0x6ed82b7f,
+	0x639b0da6, 0x675a1011, 0x791d4014, 0x7ddc5da3, 0x709f7b7a,
+	0x745e66cd, 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
+	0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, 0xbe2b5b58,
+	0xbaea46ef, 0xb7a96036, 0xb3687d81, 0xad2f2d84, 0xa9ee3033,
+	0xa4ad16ea, 0xa06c0b5d, 0xd4326d90, 0xd0f37027, 0xddb056fe,
+	0xd9714b49, 0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95,
+	0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1, 0xe13ef6f4,
+	0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, 0x34867077, 0x30476dc0,
+	0x3d044b19, 0x39c556ae, 0x278206ab, 0x23431b1c, 0x2e003dc5,
+	0x2ac12072, 0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16,
+	0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca, 0x7897ab07,
+	0x7c56b6b0, 0x71159069, 0x75d48dde, 0x6b93dddb, 0x6f52c06c,
+	0x6211e6b5, 0x66d0fb02, 0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1,
+	0x53dc6066, 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
+	0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e, 0xbfa1b04b,
+	0xbb60adfc, 0xb6238b25, 0xb2e29692, 0x8aad2b2f, 0x8e6c3698,
+	0x832f1041, 0x87ee0df6, 0x99a95df3, 0x9d684044, 0x902b669d,
+	0x94ea7b2a, 0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e,
+	0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2, 0xc6bcf05f,
+	0xc27dede8, 0xcf3ecb31, 0xcbffd686, 0xd5b88683, 0xd1799b34,
+	0xdc3abded, 0xd8fba05a, 0x690ce0ee, 0x6dcdfd59, 0x608edb80,
+	0x644fc637, 0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb,
+	0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f, 0x5c007b8a,
+	0x58c1663d, 0x558240e4, 0x51435d53, 0x251d3b9e, 0x21dc2629,
+	0x2c9f00f0, 0x285e1d47, 0x36194d42, 0x32d850f5, 0x3f9b762c,
+	0x3b5a6b9b, 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
+	0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623, 0xf12f560e,
+	0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7, 0xe22b20d2, 0xe6ea3d65,
+	0xeba91bbc, 0xef68060b, 0xd727bbb6, 0xd3e6a601, 0xdea580d8,
+	0xda649d6f, 0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3,
+	0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7, 0xae3afba2,
+	0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, 0x9b3660c6, 0x9ff77d71,
+	0x92b45ba8, 0x9675461f, 0x8832161a, 0x8cf30bad, 0x81b02d74,
+	0x857130c3, 0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640,
+	0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c, 0x7b827d21,
+	0x7f436096, 0x7200464f, 0x76c15bf8, 0x68860bfd, 0x6c47164a,
+	0x61043093, 0x65c52d24, 0x119b4be9, 0x155a565e, 0x18197087,
+	0x1cd86d30, 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
+	0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088, 0x2497d08d,
+	0x2056cd3a, 0x2d15ebe3, 0x29d4f654, 0xc5a92679, 0xc1683bce,
+	0xcc2b1d17, 0xc8ea00a0, 0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb,
+	0xdbee767c, 0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18,
+	0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4, 0x89b8fd09,
+	0x8d79e0be, 0x803ac667, 0x84fbdbd0, 0x9abc8bd5, 0x9e7d9662,
+	0x933eb0bb, 0x97ffad0c, 0xafb010b1, 0xab710d06, 0xa6322bdf,
+	0xa2f33668, 0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4,
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..42f157d
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,5 @@
+module b612.me/starcrypto
+
+go 1.16
+
+require golang.org/x/crypto v0.0.0-20220313003712-b769efc7c000
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..e7799fa
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,11 @@
+golang.org/x/crypto v0.0.0-20220313003712-b769efc7c000 h1:SL+8VVnkqyshUSz5iNnXtrBQzvFF2SkROm6t5RczFAE=
+golang.org/x/crypto v0.0.0-20220313003712-b769efc7c000/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
+golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1 h1:SrN+KX8Art/Sf4HNj6Zcz06G7VEz+7w9tdXTPOZ7+l4=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1 h1:v+OssWQX+hTHEmOBgwxdZxK4zHq3yOs8F9J7mk0PY8E=
+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=