MINOR: sample: Add sha2([<bits>]) converter
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]
diff --git a/doc/configuration.txt b/doc/configuration.txt
index 5debec1..de092dc 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -13897,9 +13897,19 @@
contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
sha1
- Converts a binary input sample to a SHA1 digest. The result is a binary
+ Converts a binary input sample to a SHA-1 digest. The result is a binary
sample with length of 20 bytes.
+sha2([<bits>])
+ Converts a binary input sample to a digest in the SHA-2 family. The result
+ is a binary sample with length of <bits>/8 bytes.
+
+ Valid values for <bits> are 224, 256, 384, 512, each corresponding to
+ SHA-<bits>. The default value is 256.
+
+ Please note that this converter is only available when haproxy has been
+ compiled with USE_OPENSSL.
+
strcmp(<var>)
Compares the contents of <var> with the input value of type string. Returns
the result as a signed integer compatible with strcmp(3): 0 if both strings