fixes send.sh test fallout on arm64 and should also fix i386 ok op@

This adds a set of functions to abstract over SHA1Init, SHA1Update, SHA1Final, their respective SHA256 variants and how to compare digests. Replace all the SHA1*() usage with the new APIs. It's a preparatory step for sha256 handling. ok stsp@

Add compatability support for sha2 for systems which don't natively have it. This has been stolen from OpenBSD. Thanks!

fixes send.sh test fallout on arm64 and should also fix i386 ok op@

ok op

This adds a set of functions to abstract over SHA1Init, SHA1Update, SHA1Final, their respective SHA256 variants and how to compare digests. Replace all the SHA1*() usage with the new APIs. It's a preparatory step for sha256 handling. ok stsp@

Don't rely on AC_RUN_IFELSE as this breaks cross-compilation (voidlinux). Although this is better replaced with AC_CHECK_DECL. In template/ include checking for libbsd.

This is included portably.

Simply the SHA detection by not predicating on libcrypto, but instead checking individual header files.

Remove sha1.h as this is found portably across systems.

sha1.c -> hash.c

it abstracts over the hash type and ensures that object ids are zero'ed before their sha1 digest is written. Needed by the incoming sha256 support. ok stsp@

It will soon grow functions to deal with sha256 too. stsp@ agrees.

In preparation for wide sha256 support; stsp@ agrees. Change done mechanically with find . -iname \*.[cy] -exec sam {} + X ,x/<sha1\.h>/i/\n#include <sha2.h>