New functions to retrieve certificate signatures and signature OID NID.

CHANGES

@@ -4,6 +4,10 @@
 
  Changes between 1.0.1 and 1.1.0  [xx XXX xxxx]
 
+  *) New functions to retrieve certificate signature and signature
+     OID NID.
+     [Steve Henson]
+
   *) Print out deprecated issuer and subject unique ID fields in
      certificates.
      [Steve Henson]

crypto/asn1/x_x509.c

@@ -192,3 +192,17 @@ int i2d_X509_AUX(X509 *a, unsigned char **pp)
 	if(a) length += i2d_X509_CERT_AUX(a->aux, pp);
 	return length;
 }
+
+void X509_get0_signature(ASN1_BIT_STRING **psig, X509_ALGOR **palg,
+				const X509 *x)
+	{
+	if (psig)
+		*psig = x->signature;
+	if (palg)
+		*palg = x->sig_alg;
+	}
+
+int X509_get_signature_nid(const X509 *x)
+	{
+	return OBJ_obj2nid(x->sig_alg->algorithm);
+	}

crypto/x509/x509.h

@@ -849,6 +849,10 @@ void *X509_get_ex_data(X509 *r, int idx);
 int		i2d_X509_AUX(X509 *a,unsigned char **pp);
 X509 *		d2i_X509_AUX(X509 **a,const unsigned char **pp,long length);
 
+void X509_get0_signature(ASN1_BIT_STRING **psig, X509_ALGOR **palg,
+								const X509 *x);
+int X509_get_signature_nid(const X509 *x);
+
 int X509_alias_set1(X509 *x, unsigned char *name, int len);
 int X509_keyid_set1(X509 *x, unsigned char *id, int len);
 unsigned char * X509_alias_get0(X509 *x, int *len);