The SHA-1 algorithm is deprecated (particularly for security-sensitive
applications) in a variety of OS environments. This already affects
RHEL-9 and derivatives, which are not willing to use certificates using
that algorithm. The fix is to use sha256 instead, which is already used
for most of the other certificates in the test suite.
Fixes#10135
This gets rid of issues related to sha1 signatures.
Manual steps after "make clean-certs" and "make build-certs":
- Copy tests/certs/stunnel-sv.pem to tests/stunnel.pem
(make clean-certs does not remove the original tests/stunnel.pem)
- Copy tests/certs/Server-localhost-sv.pubkey-pinned into --pinnedpubkey
options of tests/data/test2041 and tests/data/test2087
Closes#10153