fix(*): Vendored project dependencies

vendor/github.com/pjbgf/sha1cd/cgo/README.md

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+# sha1collisiondetection
+Library and command line tool to detect SHA-1 collisions in files
+
+Copyright 2017 Marc Stevens <marc@marc-stevens.nl>
+
+Distributed under the MIT Software License.
+
+See accompanying file LICENSE.txt or copy at https://opensource.org/licenses/MIT.
+
+## Developers
+
+- Marc Stevens, CWI Amsterdam (https://marc-stevens.nl)
+- Dan Shumow, Microsoft Research (https://www.microsoft.com/en-us/research/people/danshu/)
+
+## About
+This library and command line tool were designed as near drop-in replacements for common SHA-1 libraries and sha1sum.
+They will compute the SHA-1 hash of any given file and additionally will detect cryptanalytic collision attacks against SHA-1 present in each file. It is very fast and takes less than twice the amount of time as regular SHA-1.
+
+More specifically they will detect any cryptanalytic collision attack against SHA-1 using any of the top 32 SHA-1 disturbance vectors with probability 1:
+```
+    I(43,0), I(44,0), I(45,0), I(46,0), I(47,0), I(48,0), I(49,0), I(50,0), I(51,0), I(52,0),
+    I(46,2), I(47,2), I(48,2), I(49,2), I(50,2), I(51,2),
+    II(45,0), II(46,0), II(47,0), II(48,0), II(49,0), II(50,0), II(51,0), II(52,0), II(53,0), II(54,0), II(55,0), II(56,0),
+    II(46,2), II(49,2), II(50,2), II(51,2)
+```
+The possibility of false positives can be neglected as the probability is smaller than 2^-90.
+
+The library supports both an indicator flag that applications can check and act on, as well as a special _safe-hash_ mode that returns the real SHA-1 hash when no collision was detected and a different _safe_ hash when a collision was detected.
+Colliding files will have the same SHA-1 hash, but will have different unpredictable safe-hashes.
+This essentially enables protection of applications against SHA-1 collisions with no further changes in the application, e.g., digital signature forgeries based on SHA-1 collisions automatically become invalid.
+
+For the theoretical explanation of collision detection see the award-winning paper on _Counter-Cryptanalysis_:
+
+Counter-cryptanalysis, Marc Stevens, CRYPTO 2013, Lecture Notes in Computer Science, vol. 8042, Springer, 2013, pp. 129-146,
+https://marc-stevens.nl/research/papers/C13-S.pdf
+
+
+## Inclusion in other programs
+
+In order to make it easier to include these sources in other project
+there are several preprocessor macros that the code uses. Rather than
+copy/pasting and customizing or specializing the code, first see if
+setting any of these defines appropriately will allow you to avoid
+modifying the code yourself.
+
+- SHA1DC_NO_STANDARD_INCLUDES
+
+ Skips including standard headers. Use this if your project for
+ whatever reason wishes to do its own header includes.
+
+- SHA1DC_CUSTOM_INCLUDE_SHA1_C
+
+  Includes a custom header at the top of sha1.c. Usually this would be
+  set in conjunction with SHA1DC_NO_STANDARD_INCLUDES to point to a
+  header file which includes various standard headers.
+
+- SHA1DC_INIT_SAFE_HASH_DEFAULT
+
+  Sets the default for safe_hash in SHA1DCInit(). Valid values are 0
+  and 1. If unset 1 is the default.
+
+- SHA1DC_CUSTOM_TRAILING_INCLUDE_SHA1_C
+
+  Includes a custom trailer in sha1.c. Useful for any extra utility
+  functions that make use of the functions already defined in sha1.c.
+
+- SHA1DC_CUSTOM_TRAILING_INCLUDE_SHA1_H
+
+  Includes a custom trailer in sha1.h. Useful for defining the
+  prototypes of the functions or code included by
+  SHA1DC_CUSTOM_TRAILING_INCLUDE_SHA1_C.
+
+- SHA1DC_CUSTOM_INCLUDE_UBC_CHECK_C
+
+  Includes a custom header at the top of ubc_check.c.
+
+- SHA1DC_CUSTOM_TRAILING_INCLUDE_UBC_CHECK_C
+
+  Includes a custom trailer in ubc_check.c.
+
+- SHA1DC_CUSTOM_TRAILING_INCLUDE_UBC_CHECK_H
+
+  Includes a custom trailer in ubc_check.H.
+
+This code will try to auto-detect certain things based on
+CPU/platform. Unless you're running on some really obscure CPU or
+porting to a new platform you should not need to tweak this. If you do
+please open an issue at
+https://github.com/cr-marcstevens/sha1collisiondetection
+
+- SHA1DC_FORCE_LITTLEENDIAN / SHA1DC_FORCE_BIGENDIAN
+
+  Override the check for processor endianenss and force either
+  Little-Endian or Big-Endian.
+
+- SHA1DC_FORCE_UNALIGNED_ACCESS
+
+  Permit unaligned access. This will fail on e.g. SPARC processors, so
+  it's only permitted on a whitelist of processors. If your CPU isn't
+  detected as allowing this, and allows unaligned access, setting this
+  may improve performance (or make it worse, if the kernel has to
+  catch and emulate such access on its own).