Add the ability to set OCSP_RESPID fields

OCSP_RESPID was made opaque in 1.1.0, but no accessors were provided for
setting the name/key value for the OCSP_RESPID.

Reviewed-by: Rich Salz <rsalz@openssl.org>

doc/crypto/OCSP_response_status.pod

diff --git a/doc/crypto/OCSP_response_status.pod b/doc/crypto/OCSP_response_status.pod
index 08738d2..993fce2 100644
--- a/doc/crypto/OCSP_response_status.pod
+++ b/doc/crypto/OCSP_response_status.pod
@@ -3,7 +3,8 @@
 =head1 NAME
 
 OCSP_response_status, OCSP_response_get1_basic, OCSP_response_create,
-OCSP_RESPONSE_free - OCSP response functions
+OCSP_RESPONSE_free, OCSP_RESPID_set_by_name,
+OCSP_RESPID_set_by_key - OCSP response functions
 
 =head1 SYNOPSIS
 
@@ -14,6 +15,9 @@
  OCSP_RESPONSE *OCSP_response_create(int status, OCSP_BASICRESP *bs);
  void OCSP_RESPONSE_free(OCSP_RESPONSE *resp);
 
+ int OCSP_RESPID_set_by_name(OCSP_RESPID *respid, X509 *cert);
+ int OCSP_RESPID_set_by_key(OCSP_RESPID *respid, X509 *cert);
+
 =head1 DESCRIPTION
 
 OCSP_response_status() returns the OCSP response status of B<resp>. It returns
@@ -30,6 +34,17 @@
 
 OCSP_RESPONSE_free() frees up OCSP response B<resp>.
 
+OCSP_RESPID_set_by_name() sets the name of the OCSP_RESPID to be the same as the
+subject name in the supplied X509 certificate B<cert> for the OCSP responder.
+
+OCSP_RESPID_set_by_key() sets the key of the OCSP_RESPID to be the same as the
+key in the supplied X509 certificate B<cert> for the OCSP responder. The key is
+stored as a SHA1 hash.
+
+Note that an OCSP_RESPID can only have one of the name, or the key set. Calling
+OCSP_RESPID_set_by_name() or OCSP_RESPID_set_by_key() will clear any existing
+setting.
+
 =head1 RETURN VALUES
 
 OCSP_RESPONSE_status() returns a status value.
@@ -42,6 +57,9 @@
 
 OCSP_RESPONSE_free() does not return a value.
 
+OCSP_RESPID_set_by_name() and OCSP_RESPID_set_by_key() return 1 on success or 0
+on failure.
+
 =head1 NOTES
 
 OCSP_response_get1_basic() is only called if the status of a response is
@@ -55,6 +73,13 @@
 L<OCSP_REQUEST_new(3)>
 L<OCSP_response_find_status(3)>
 L<OCSP_sendreq_new(3)>
+L<OCSP_RESPID_new(3)>
+L<OCSP_RESPID_free(3)>
+
+=head1 HISTORY
+
+The OCSP_RESPID_set_by_name() and OCSP_RESPID_set_by_key() functions were added
+in OpenSSL version 1.1.0a.
 
 =head1 COPYRIGHT