Constify some X509_CRL, X509_REQ functions.

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

crypto/x509/x509_req.c

@@ -267,12 +267,12 @@ int X509_REQ_add1_attr_by_txt(X509_REQ *req,
     return 0;
 }
 
-long X509_REQ_get_version(X509_REQ *req)
+long X509_REQ_get_version(const X509_REQ *req)
 {
     return ASN1_INTEGER_get(req->req_info.version);
 }
 
-X509_NAME *X509_REQ_get_subject_name(X509_REQ *req)
+X509_NAME *X509_REQ_get_subject_name(const X509_REQ *req)
 {
     return req->req_info.subject;
 }

doc/crypto/X509_get_subject_name.pod

@@ -17,10 +17,10 @@ subject names
  X509_NAME *X509_get_issuer_name(const X509 *x);
  int X509_set_issuer_name(X509 *x, X509_NAME *name);
 
- X509_NAME *X509_REQ_get_subject_name(X509_REQ *req);
+ X509_NAME *X509_REQ_get_subject_name(const X509_REQ *req);
  int X509_REQ_set_subject_name(X509_REQ *req, X509_NAME *name);
 
- X509_NAME *X509_CRL_get_issuer(X509_CRL *crl);
+ X509_NAME *X509_CRL_get_issuer(const X509_CRL *crl);
  int X509_CRL_set_issuer_name(X509_CRL *x, X509_NAME *name);
 
 =head1 DESCRIPTION

doc/crypto/X509_get_version.pod

@@ -13,10 +13,10 @@ certificate request or CRL version
  long X509_get_version(const X509 *x);
  int X509_set_version(X509 *x, long version);
 
- long X509_REQ_get_version(X509_REQ *req);
+ long X509_REQ_get_version(const X509_REQ *req);
  int X509_REQ_set_version(X509_REQ *x, long version);
 
- long X509_CRL_get_version(X509_CRL *crl);
+ long X509_CRL_get_version(const X509_CRL *crl);
  int X509_CRL_set_version(X509_CRL *x, long version);
 
 =head1 DESCRIPTION

include/openssl/x509.h

@@ -638,9 +638,9 @@ EVP_PKEY *X509_get_pubkey(X509 *x);
 ASN1_BIT_STRING *X509_get0_pubkey_bitstr(const X509 *x);
 int X509_certificate_type(X509 *x, EVP_PKEY *pubkey /* optional */ );
 
-long X509_REQ_get_version(X509_REQ *req);
+long X509_REQ_get_version(const X509_REQ *req);
 int X509_REQ_set_version(X509_REQ *x, long version);
-X509_NAME *X509_REQ_get_subject_name(X509_REQ *req);
+X509_NAME *X509_REQ_get_subject_name(const X509_REQ *req);
 int X509_REQ_set_subject_name(X509_REQ *req, X509_NAME *name);
 void X509_REQ_get0_signature(ASN1_BIT_STRING **psig, X509_ALGOR **palg,
                              X509_REQ *req);
@@ -681,10 +681,10 @@ int X509_CRL_set_nextUpdate(X509_CRL *x, const ASN1_TIME *tm);
 int X509_CRL_sort(X509_CRL *crl);
 int X509_CRL_up_ref(X509_CRL *crl);
 
-long X509_CRL_get_version(X509_CRL *crl);
-ASN1_TIME *X509_CRL_get_lastUpdate(X509_CRL *crl);
-ASN1_TIME *X509_CRL_get_nextUpdate(X509_CRL *crl);
-X509_NAME *X509_CRL_get_issuer(X509_CRL *crl);
+long X509_CRL_get_version(const X509_CRL *crl);
+ASN1_TIME *X509_CRL_get_lastUpdate(const X509_CRL *crl);
+ASN1_TIME *X509_CRL_get_nextUpdate(const X509_CRL *crl);
+X509_NAME *X509_CRL_get_issuer(const X509_CRL *crl);
 STACK_OF(X509_EXTENSION) *X509_CRL_get0_extensions(X509_CRL *crl);
 STACK_OF(X509_REVOKED) *X509_CRL_get_REVOKED(X509_CRL *crl);
 void X509_CRL_get0_signature(ASN1_BIT_STRING **psig, X509_ALGOR **palg,