Tolerate some "variations" used in some

certificates.

One is a valid CA which has no basicConstraints
but does have certSign keyUsage.

Other is S/MIME signer with nonRepudiation but
no digitalSignature.

CHANGES

@@ -3,6 +3,10 @@
 
  Changes between 0.9.6 and 0.9.7  [xx XXX 2000]
 
+  *) Tolerate nonRepudiation as being valid for S/MIME signing and certSign
+     keyUsage if basicConstraints absent for a CA.
+     [Steve Henson]
+
   *) Make SMIME_write_PKCS7() write mail header values with a format that
      is more generally accepted (no spaces before the semicolon), since
      some programs can't parse those values properly otherwise.  Also make

crypto/x509v3/v3_purp.c

@@ -371,6 +371,8 @@ static int ca_check(const X509 *x)
 		else return 0;
 	} else {
 		if((x->ex_flags & V1_ROOT) == V1_ROOT) return 3;
+		/* If key usage present it must have certSign so tolerate it */
+		else if (x->ex_flags & EXFLAG_KUSAGE) return 3;
 		else return 2;
 	}
 }
@@ -455,7 +457,7 @@ static int check_purpose_smime_sign(const X509_PURPOSE *xp, const X509 *x, int c
 	int ret;
 	ret = purpose_smime(x, ca);
 	if(!ret || ca) return ret;
-	if(ku_reject(x, KU_DIGITAL_SIGNATURE)) return 0;
+	if(ku_reject(x, KU_DIGITAL_SIGNATURE|KU_NON_REPUDIATION)) return 0;
 	return ret;
 }