Instead of failing the conversion when an invalid number of bits is
given the sha2 converter now fails with an appropriate error message
during startup.
The sha2 converter was introduced in d437630237,
which is in 2.1 and higher.
Previously an expression like:
path,field(2,/) -m found
always returned `true`.
Bug exists since the `field` converter exists. That is:
f399b0debf
The fix should be backported to 1.6+.
This adds a converter for the SHA-2 family, supporting SHA-224, SHA-256
SHA-384 and SHA-512.
The converter relies on the OpenSSL implementation, thus only being available
when HAProxy is compiled with USE_OPENSSL.
See GitHub issue #123. The hypothetical `ssl_?_sha256` fetch can then be
simulated using `ssl_?_der,sha2(256)`:
http-response set-header Server-Cert-FP %[ssl_f_der,sha2(256),hex]