Add CRC64-NVMe

postmodern · Jan 6, 2025 · c7747d6 · c7747d6
1 parent 9e50ddf
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diff --git a/README.md b/README.md
@@ -40,6 +40,7 @@ module.
   * [CRC32 XFER](https://rubydoc.info/gems/digest-crc/Digest/CRC32XFER)
   * [CRC64](https://rubydoc.info/gems/digest-crc/Digest/CRC64)
   * [CRC64 Jones](https://rubydoc.info/gems/digest-crc/Digest/CRC64Jones)
+  * [CRC64 NVMe](https://rubydoc.info/gems/digest-crc/Digest/CRC64Nvme)
   * [CRC64 XZ](https://rubydoc.info/gems/digest-crc/Digest/CRC64XZ)
 * Pure Ruby implementation.
 * Provides CRC Tables for optimized calculations.

diff --git a/benchmarks.rb b/benchmarks.rb
@@ -29,6 +29,7 @@
   'crc32_xfer'    => 'CRC32XFER',
   'crc64'         => 'CRC64',
   'crc64_jones'   => 'CRC64Jones',
+  'crc64_nvme'   => 'CRC64NVMe',
   'crc64_xz'      => 'CRC64XZ',
 }
 

diff --git a/ext/digest/crc64_nvme/crc64_nvme.c b/ext/digest/crc64_nvme/crc64_nvme.c
@@ -0,0 +1,102 @@
+/**
+ * \file
+ * Functions and types for CRC checks.
+ *
+ * Generated on Mon Jan  6 09:50:24 2025
+ * by pycrc v0.10.0, https://pycrc.org
+ * using the configuration:
+ *  - Width		 = 64
+ *  - Poly		  = 0xad93d23594c93659
+ *  - XorIn		 = 0xffffffffffffffff
+ *  - ReflectIn	 = True
+ *  - XorOut		= 0xffffffffffffffff
+ *  - ReflectOut	= True
+ *  - Algorithm	 = table-driven
+ */
+
+#include "crc64_nvme.h"
+
+/**
+ * Static table used for the table_driven implementation.
+ */
+static const crc64_t crc64_table[256] = {
+	0x0000000000000000, 0x7f6ef0c830358979, 0xfedde190606b12f2, 0x81b31158505e9b8b,
+	0xc962e5739841b68f, 0xb60c15bba8743ff6, 0x37bf04e3f82aa47d, 0x48d1f42bc81f2d04,
+	0xa61cecb46814fe75, 0xd9721c7c5821770c, 0x58c10d24087fec87, 0x27affdec384a65fe,
+	0x6f7e09c7f05548fa, 0x1010f90fc060c183, 0x91a3e857903e5a08, 0xeecd189fa00bd371,
+	0x78e0ff3b88be6f81, 0x078e0ff3b88be6f8, 0x863d1eabe8d57d73, 0xf953ee63d8e0f40a,
+	0xb1821a4810ffd90e, 0xceecea8020ca5077, 0x4f5ffbd87094cbfc, 0x30310b1040a14285,
+	0xdefc138fe0aa91f4, 0xa192e347d09f188d, 0x2021f21f80c18306, 0x5f4f02d7b0f40a7f,
+	0x179ef6fc78eb277b, 0x68f0063448deae02, 0xe943176c18803589, 0x962de7a428b5bcf0,
+	0xf1c1fe77117cdf02, 0x8eaf0ebf2149567b, 0x0f1c1fe77117cdf0, 0x7072ef2f41224489,
+	0x38a31b04893d698d, 0x47cdebccb908e0f4, 0xc67efa94e9567b7f, 0xb9100a5cd963f206,
+	0x57dd12c379682177, 0x28b3e20b495da80e, 0xa900f35319033385, 0xd66e039b2936bafc,
+	0x9ebff7b0e12997f8, 0xe1d10778d11c1e81, 0x606216208142850a, 0x1f0ce6e8b1770c73,
+	0x8921014c99c2b083, 0xf64ff184a9f739fa, 0x77fce0dcf9a9a271, 0x08921014c99c2b08,
+	0x4043e43f0183060c, 0x3f2d14f731b68f75, 0xbe9e05af61e814fe, 0xc1f0f56751dd9d87,
+	0x2f3dedf8f1d64ef6, 0x50531d30c1e3c78f, 0xd1e00c6891bd5c04, 0xae8efca0a188d57d,
+	0xe65f088b6997f879, 0x9931f84359a27100, 0x1882e91b09fcea8b, 0x67ec19d339c963f2,
+	0xd75adabd7a6e2d6f, 0xa8342a754a5ba416, 0x29873b2d1a053f9d, 0x56e9cbe52a30b6e4,
+	0x1e383fcee22f9be0, 0x6156cf06d21a1299, 0xe0e5de5e82448912, 0x9f8b2e96b271006b,
+	0x71463609127ad31a, 0x0e28c6c1224f5a63, 0x8f9bd7997211c1e8, 0xf0f5275142244891,
+	0xb824d37a8a3b6595, 0xc74a23b2ba0eecec, 0x46f932eaea507767, 0x3997c222da65fe1e,
+	0xafba2586f2d042ee, 0xd0d4d54ec2e5cb97, 0x5167c41692bb501c, 0x2e0934dea28ed965,
+	0x66d8c0f56a91f461, 0x19b6303d5aa47d18, 0x980521650afae693, 0xe76bd1ad3acf6fea,
+	0x09a6c9329ac4bc9b, 0x76c839faaaf135e2, 0xf77b28a2faafae69, 0x8815d86aca9a2710,
+	0xc0c42c4102850a14, 0xbfaadc8932b0836d, 0x3e19cdd162ee18e6, 0x41773d1952db919f,
+	0x269b24ca6b12f26d, 0x59f5d4025b277b14, 0xd846c55a0b79e09f, 0xa72835923b4c69e6,
+	0xeff9c1b9f35344e2, 0x90973171c366cd9b, 0x1124202993385610, 0x6e4ad0e1a30ddf69,
+	0x8087c87e03060c18, 0xffe938b633338561, 0x7e5a29ee636d1eea, 0x0134d92653589793,
+	0x49e52d0d9b47ba97, 0x368bddc5ab7233ee, 0xb738cc9dfb2ca865, 0xc8563c55cb19211c,
+	0x5e7bdbf1e3ac9dec, 0x21152b39d3991495, 0xa0a63a6183c78f1e, 0xdfc8caa9b3f20667,
+	0x97193e827bed2b63, 0xe877ce4a4bd8a21a, 0x69c4df121b863991, 0x16aa2fda2bb3b0e8,
+	0xf86737458bb86399, 0x8709c78dbb8deae0, 0x06bad6d5ebd3716b, 0x79d4261ddbe6f812,
+	0x3105d23613f9d516, 0x4e6b22fe23cc5c6f, 0xcfd833a67392c7e4, 0xb0b6c36e43a74e9d,
+	0x9a6c9329ac4bc9b5, 0xe50263e19c7e40cc, 0x64b172b9cc20db47, 0x1bdf8271fc15523e,
+	0x530e765a340a7f3a, 0x2c608692043ff643, 0xadd397ca54616dc8, 0xd2bd67026454e4b1,
+	0x3c707f9dc45f37c0, 0x431e8f55f46abeb9, 0xc2ad9e0da4342532, 0xbdc36ec59401ac4b,
+	0xf5129aee5c1e814f, 0x8a7c6a266c2b0836, 0x0bcf7b7e3c7593bd, 0x74a18bb60c401ac4,
+	0xe28c6c1224f5a634, 0x9de29cda14c02f4d, 0x1c518d82449eb4c6, 0x633f7d4a74ab3dbf,
+	0x2bee8961bcb410bb, 0x548079a98c8199c2, 0xd53368f1dcdf0249, 0xaa5d9839ecea8b30,
+	0x449080a64ce15841, 0x3bfe706e7cd4d138, 0xba4d61362c8a4ab3, 0xc52391fe1cbfc3ca,
+	0x8df265d5d4a0eece, 0xf29c951de49567b7, 0x732f8445b4cbfc3c, 0x0c41748d84fe7545,
+	0x6bad6d5ebd3716b7, 0x14c39d968d029fce, 0x95708ccedd5c0445, 0xea1e7c06ed698d3c,
+	0xa2cf882d2576a038, 0xdda178e515432941, 0x5c1269bd451db2ca, 0x237c997575283bb3,
+	0xcdb181ead523e8c2, 0xb2df7122e51661bb, 0x336c607ab548fa30, 0x4c0290b2857d7349,
+	0x04d364994d625e4d, 0x7bbd94517d57d734, 0xfa0e85092d094cbf, 0x856075c11d3cc5c6,
+	0x134d926535897936, 0x6c2362ad05bcf04f, 0xed9073f555e26bc4, 0x92fe833d65d7e2bd,
+	0xda2f7716adc8cfb9, 0xa54187de9dfd46c0, 0x24f29686cda3dd4b, 0x5b9c664efd965432,
+	0xb5517ed15d9d8743, 0xca3f8e196da80e3a, 0x4b8c9f413df695b1, 0x34e26f890dc31cc8,
+	0x7c339ba2c5dc31cc, 0x035d6b6af5e9b8b5, 0x82ee7a32a5b7233e, 0xfd808afa9582aa47,
+	0x4d364994d625e4da, 0x3258b95ce6106da3, 0xb3eba804b64ef628, 0xcc8558cc867b7f51,
+	0x8454ace74e645255, 0xfb3a5c2f7e51db2c, 0x7a894d772e0f40a7, 0x05e7bdbf1e3ac9de,
+	0xeb2aa520be311aaf, 0x944455e88e0493d6, 0x15f744b0de5a085d, 0x6a99b478ee6f8124,
+	0x224840532670ac20, 0x5d26b09b16452559, 0xdc95a1c3461bbed2, 0xa3fb510b762e37ab,
+	0x35d6b6af5e9b8b5b, 0x4ab846676eae0222, 0xcb0b573f3ef099a9, 0xb465a7f70ec510d0,
+	0xfcb453dcc6da3dd4, 0x83daa314f6efb4ad, 0x0269b24ca6b12f26, 0x7d0742849684a65f,
+	0x93ca5a1b368f752e, 0xeca4aad306bafc57, 0x6d17bb8b56e467dc, 0x12794b4366d1eea5,
+	0x5aa8bf68aecec3a1, 0x25c64fa09efb4ad8, 0xa4755ef8cea5d153, 0xdb1bae30fe90582a,
+	0xbcf7b7e3c7593bd8, 0xc399472bf76cb2a1, 0x422a5673a732292a, 0x3d44a6bb9707a053,
+	0x759552905f188d57, 0x0afba2586f2d042e, 0x8b48b3003f739fa5, 0xf42643c80f4616dc,
+	0x1aeb5b57af4dc5ad, 0x6585ab9f9f784cd4, 0xe436bac7cf26d75f, 0x9b584a0fff135e26,
+	0xd389be24370c7322, 0xace74eec0739fa5b, 0x2d545fb4576761d0, 0x523aaf7c6752e8a9,
+	0xc41748d84fe75459, 0xbb79b8107fd2dd20, 0x3acaa9482f8c46ab, 0x45a459801fb9cfd2,
+	0x0d75adabd7a6e2d6, 0x721b5d63e7936baf, 0xf3a84c3bb7cdf024, 0x8cc6bcf387f8795d,
+	0x620ba46c27f3aa2c, 0x1d6554a417c62355, 0x9cd645fc4798b8de, 0xe3b8b53477ad31a7,
+	0xab69411fbfb21ca3, 0xd407b1d78f8795da, 0x55b4a08fdfd90e51, 0x2ada5047efec8728
+};
+
+crc64_t crc64_nvme_update(crc64_t crc, const void *data, size_t data_len)
+{
+	const unsigned char *d = (const unsigned char *)data;
+	unsigned int tbl_idx;
+
+	while (data_len--)
+	{
+		tbl_idx = (crc ^ *d) & 0xff;
+		crc = (crc64_table[tbl_idx] ^ (crc >> 8)) & 0xffffffffffffffff;
+		d++;
+	}
+
+	return crc & 0xffffffffffffffff;
+}
diff --git a/ext/digest/crc64_nvme/crc64_nvme.h b/ext/digest/crc64_nvme/crc64_nvme.h
@@ -0,0 +1,8 @@
+#ifndef _CRC64_NVME_H_
+#define _CRC64_NVME_H_
+
+#include "../crc64/crc64.h"
+
+crc64_t crc64_nvme_update(crc64_t crc, const void *data, size_t data_len);
+
+#endif
diff --git a/ext/digest/crc64_nvme/crc64_nvme_ext.c b/ext/digest/crc64_nvme/crc64_nvme_ext.c
@@ -0,0 +1,31 @@
+#include "ruby.h"
+#include "extconf.h"
+
+#include "crc64_nvme.h"
+
+VALUE Digest_CRC64NVMe_update(VALUE self, VALUE data)
+{
+	VALUE crc_ivar_name = rb_intern("@crc");
+	VALUE crc_ivar = rb_ivar_get(self, crc_ivar_name);
+	crc64_t crc = NUM2ULONG(crc_ivar);
+
+	const char *data_ptr = StringValuePtr(data);
+	size_t length = RSTRING_LEN(data);
+
+	crc = crc64_nvme_update(crc,data_ptr,length);
+
+	rb_ivar_set(self, crc_ivar_name, ULONG2NUM(crc));
+	return self;
+}
+
+void Init_crc64_nvme_ext()
+{
+	VALUE mDigest = rb_const_get(rb_cObject, rb_intern("Digest"));
+	VALUE cCRC64NVMe = rb_const_get(mDigest, rb_intern("CRC64NVMe"));
+
+	#ifdef HAVE_RB_EXT_RACTOR_SAFE
+		rb_ext_ractor_safe(true);
+	#endif
+
+	rb_define_method(cCRC64NVMe, "update", Digest_CRC64NVMe_update, 1);
+}
diff --git a/ext/digest/crc64_nvme/extconf.rb b/ext/digest/crc64_nvme/extconf.rb
@@ -0,0 +1,7 @@
+require 'mkmf'
+
+have_header("stdint.h")
+have_header('stddef.h')
+
+create_header
+create_makefile "crc64_nvme_ext"
diff --git a/lib/digest/crc64_nvme.rb b/lib/digest/crc64_nvme.rb
@@ -0,0 +1,90 @@
+require 'digest/crc64'
+
+module Digest
+  #
+  # Implements the CRC64 Jones algorithm.
+  #
+  # @since 0.5.0
+  #
+  class CRC64NVMe < CRC64
+
+    INIT_XOR = 0xffffffffffffffff
+
+    INIT_CRC = 0x0 ^ INIT_XOR
+
+    XOR_MASK = 0xffffffffffffffff
+
+    # Generated by `./pycrc.py --algorithm=table-driven --width 64 --poly 0xad93d23594c93659 --reflect-in True --xor-in 0xffffffffffffffff --reflect-out True --xor-out 0xffffffffffffffff --generate=c`
+    TABLE = [
+      0x0000000000000000, 0x7f6ef0c830358979, 0xfedde190606b12f2, 0x81b31158505e9b8b,
+      0xc962e5739841b68f, 0xb60c15bba8743ff6, 0x37bf04e3f82aa47d, 0x48d1f42bc81f2d04,
+      0xa61cecb46814fe75, 0xd9721c7c5821770c, 0x58c10d24087fec87, 0x27affdec384a65fe,
+      0x6f7e09c7f05548fa, 0x1010f90fc060c183, 0x91a3e857903e5a08, 0xeecd189fa00bd371,
+      0x78e0ff3b88be6f81, 0x078e0ff3b88be6f8, 0x863d1eabe8d57d73, 0xf953ee63d8e0f40a,
+      0xb1821a4810ffd90e, 0xceecea8020ca5077, 0x4f5ffbd87094cbfc, 0x30310b1040a14285,
+      0xdefc138fe0aa91f4, 0xa192e347d09f188d, 0x2021f21f80c18306, 0x5f4f02d7b0f40a7f,
+      0x179ef6fc78eb277b, 0x68f0063448deae02, 0xe943176c18803589, 0x962de7a428b5bcf0,
+      0xf1c1fe77117cdf02, 0x8eaf0ebf2149567b, 0x0f1c1fe77117cdf0, 0x7072ef2f41224489,
+      0x38a31b04893d698d, 0x47cdebccb908e0f4, 0xc67efa94e9567b7f, 0xb9100a5cd963f206,
+      0x57dd12c379682177, 0x28b3e20b495da80e, 0xa900f35319033385, 0xd66e039b2936bafc,
+      0x9ebff7b0e12997f8, 0xe1d10778d11c1e81, 0x606216208142850a, 0x1f0ce6e8b1770c73,
+      0x8921014c99c2b083, 0xf64ff184a9f739fa, 0x77fce0dcf9a9a271, 0x08921014c99c2b08,
+      0x4043e43f0183060c, 0x3f2d14f731b68f75, 0xbe9e05af61e814fe, 0xc1f0f56751dd9d87,
+      0x2f3dedf8f1d64ef6, 0x50531d30c1e3c78f, 0xd1e00c6891bd5c04, 0xae8efca0a188d57d,
+      0xe65f088b6997f879, 0x9931f84359a27100, 0x1882e91b09fcea8b, 0x67ec19d339c963f2,
+      0xd75adabd7a6e2d6f, 0xa8342a754a5ba416, 0x29873b2d1a053f9d, 0x56e9cbe52a30b6e4,
+      0x1e383fcee22f9be0, 0x6156cf06d21a1299, 0xe0e5de5e82448912, 0x9f8b2e96b271006b,
+      0x71463609127ad31a, 0x0e28c6c1224f5a63, 0x8f9bd7997211c1e8, 0xf0f5275142244891,
+      0xb824d37a8a3b6595, 0xc74a23b2ba0eecec, 0x46f932eaea507767, 0x3997c222da65fe1e,
+      0xafba2586f2d042ee, 0xd0d4d54ec2e5cb97, 0x5167c41692bb501c, 0x2e0934dea28ed965,
+      0x66d8c0f56a91f461, 0x19b6303d5aa47d18, 0x980521650afae693, 0xe76bd1ad3acf6fea,
+      0x09a6c9329ac4bc9b, 0x76c839faaaf135e2, 0xf77b28a2faafae69, 0x8815d86aca9a2710,
+      0xc0c42c4102850a14, 0xbfaadc8932b0836d, 0x3e19cdd162ee18e6, 0x41773d1952db919f,
+      0x269b24ca6b12f26d, 0x59f5d4025b277b14, 0xd846c55a0b79e09f, 0xa72835923b4c69e6,
+      0xeff9c1b9f35344e2, 0x90973171c366cd9b, 0x1124202993385610, 0x6e4ad0e1a30ddf69,
+      0x8087c87e03060c18, 0xffe938b633338561, 0x7e5a29ee636d1eea, 0x0134d92653589793,
+      0x49e52d0d9b47ba97, 0x368bddc5ab7233ee, 0xb738cc9dfb2ca865, 0xc8563c55cb19211c,
+      0x5e7bdbf1e3ac9dec, 0x21152b39d3991495, 0xa0a63a6183c78f1e, 0xdfc8caa9b3f20667,
+      0x97193e827bed2b63, 0xe877ce4a4bd8a21a, 0x69c4df121b863991, 0x16aa2fda2bb3b0e8,
+      0xf86737458bb86399, 0x8709c78dbb8deae0, 0x06bad6d5ebd3716b, 0x79d4261ddbe6f812,
+      0x3105d23613f9d516, 0x4e6b22fe23cc5c6f, 0xcfd833a67392c7e4, 0xb0b6c36e43a74e9d,
+      0x9a6c9329ac4bc9b5, 0xe50263e19c7e40cc, 0x64b172b9cc20db47, 0x1bdf8271fc15523e,
+      0x530e765a340a7f3a, 0x2c608692043ff643, 0xadd397ca54616dc8, 0xd2bd67026454e4b1,
+      0x3c707f9dc45f37c0, 0x431e8f55f46abeb9, 0xc2ad9e0da4342532, 0xbdc36ec59401ac4b,
+      0xf5129aee5c1e814f, 0x8a7c6a266c2b0836, 0x0bcf7b7e3c7593bd, 0x74a18bb60c401ac4,
+      0xe28c6c1224f5a634, 0x9de29cda14c02f4d, 0x1c518d82449eb4c6, 0x633f7d4a74ab3dbf,
+      0x2bee8961bcb410bb, 0x548079a98c8199c2, 0xd53368f1dcdf0249, 0xaa5d9839ecea8b30,
+      0x449080a64ce15841, 0x3bfe706e7cd4d138, 0xba4d61362c8a4ab3, 0xc52391fe1cbfc3ca,
+      0x8df265d5d4a0eece, 0xf29c951de49567b7, 0x732f8445b4cbfc3c, 0x0c41748d84fe7545,
+      0x6bad6d5ebd3716b7, 0x14c39d968d029fce, 0x95708ccedd5c0445, 0xea1e7c06ed698d3c,
+      0xa2cf882d2576a038, 0xdda178e515432941, 0x5c1269bd451db2ca, 0x237c997575283bb3,
+      0xcdb181ead523e8c2, 0xb2df7122e51661bb, 0x336c607ab548fa30, 0x4c0290b2857d7349,
+      0x04d364994d625e4d, 0x7bbd94517d57d734, 0xfa0e85092d094cbf, 0x856075c11d3cc5c6,
+      0x134d926535897936, 0x6c2362ad05bcf04f, 0xed9073f555e26bc4, 0x92fe833d65d7e2bd,
+      0xda2f7716adc8cfb9, 0xa54187de9dfd46c0, 0x24f29686cda3dd4b, 0x5b9c664efd965432,
+      0xb5517ed15d9d8743, 0xca3f8e196da80e3a, 0x4b8c9f413df695b1, 0x34e26f890dc31cc8,
+      0x7c339ba2c5dc31cc, 0x035d6b6af5e9b8b5, 0x82ee7a32a5b7233e, 0xfd808afa9582aa47,
+      0x4d364994d625e4da, 0x3258b95ce6106da3, 0xb3eba804b64ef628, 0xcc8558cc867b7f51,
+      0x8454ace74e645255, 0xfb3a5c2f7e51db2c, 0x7a894d772e0f40a7, 0x05e7bdbf1e3ac9de,
+      0xeb2aa520be311aaf, 0x944455e88e0493d6, 0x15f744b0de5a085d, 0x6a99b478ee6f8124,
+      0x224840532670ac20, 0x5d26b09b16452559, 0xdc95a1c3461bbed2, 0xa3fb510b762e37ab,
+      0x35d6b6af5e9b8b5b, 0x4ab846676eae0222, 0xcb0b573f3ef099a9, 0xb465a7f70ec510d0,
+      0xfcb453dcc6da3dd4, 0x83daa314f6efb4ad, 0x0269b24ca6b12f26, 0x7d0742849684a65f,
+      0x93ca5a1b368f752e, 0xeca4aad306bafc57, 0x6d17bb8b56e467dc, 0x12794b4366d1eea5,
+      0x5aa8bf68aecec3a1, 0x25c64fa09efb4ad8, 0xa4755ef8cea5d153, 0xdb1bae30fe90582a,
+      0xbcf7b7e3c7593bd8, 0xc399472bf76cb2a1, 0x422a5673a732292a, 0x3d44a6bb9707a053,
+      0x759552905f188d57, 0x0afba2586f2d042e, 0x8b48b3003f739fa5, 0xf42643c80f4616dc,
+      0x1aeb5b57af4dc5ad, 0x6585ab9f9f784cd4, 0xe436bac7cf26d75f, 0x9b584a0fff135e26,
+      0xd389be24370c7322, 0xace74eec0739fa5b, 0x2d545fb4576761d0, 0x523aaf7c6752e8a9,
+      0xc41748d84fe75459, 0xbb79b8107fd2dd20, 0x3acaa9482f8c46ab, 0x45a459801fb9cfd2,
+      0x0d75adabd7a6e2d6, 0x721b5d63e7936baf, 0xf3a84c3bb7cdf024, 0x8cc6bcf387f8795d,
+      0x620ba46c27f3aa2c, 0x1d6554a417c62355, 0x9cd645fc4798b8de, 0xe3b8b53477ad31a7,
+      0xab69411fbfb21ca3, 0xd407b1d78f8795da, 0x55b4a08fdfd90e51, 0x2ada5047efec8728
+        ].freeze
+
+  end
+end
+
+if RUBY_ENGINE == 'ruby'
+  begin; require 'digest/crc64_nvme/crc64_nvme_ext'; rescue LoadError; end
+end
diff --git a/spec/crc64_nvme_spec.rb b/spec/crc64_nvme_spec.rb
@@ -0,0 +1,10 @@
+require 'spec_helper'
+require 'crc_examples'
+require 'digest/crc64_nvme'
+
+describe Digest::CRC64NVMe do
+  let(:string)   { '1234567890' }
+  let(:expected) { '6025a582347b79f3' }
+
+  it_should_behave_like "CRC"
+end