New compatability trust and purpose settings.

CHANGES

@@ -4,6 +4,18 @@
 
  Changes between 0.9.5 and 0.9.5a  [XX XXX 2000]
 
+  *) Add compatability options to the purpose and trust code. The
+     purpose X509_PURPOSE_ANY is "any purpose" which automatically
+     accepts a certificate or CA, this was the previous behaviour,
+     with all the associated security issues.
+
+     X509_TRUST_COMPAT is the old trust behaviour: only and
+     automatically trust self signed roots in certificate store. A
+     new trust setting X509_TRUST_DEFAULT is used to specify that
+     a purpose has no associated trust setting and it should instead
+     use the value in the default purpose.
+     [Steve Henson]
+
   *) Fix the PKCS#8 DSA private key code so it decodes keys again
      and fix a memory leak.
      [Steve Henson]

crypto/x509/x509.h

@@ -284,7 +284,9 @@ DECLARE_STACK_OF(X509_TRUST)
 
 /* standard trust ids */
 
-#define X509_TRUST_ANY		1
+#define X509_TRUST_DEFAULT	-1	/* Only valid in purpose settings */
+
+#define X509_TRUST_COMPAT	1
 #define X509_TRUST_SSL_CLIENT	2
 #define X509_TRUST_SSL_SERVER	3
 #define X509_TRUST_EMAIL	4

crypto/x509/x509_trs.c

@@ -65,7 +65,7 @@ static int tr_cmp(X509_TRUST **a, X509_TRUST **b);
 static void trtable_free(X509_TRUST *p);
 
 static int trust_1oidany(X509_TRUST *trust, X509 *x, int flags);
-static int trust_any(X509_TRUST *trust, X509 *x, int flags);
+static int trust_compat(X509_TRUST *trust, X509 *x, int flags);
 
 static int obj_trust(int id, X509 *x, int flags);
 static int (*default_trust)(int id, X509 *x, int flags) = obj_trust;
@@ -76,7 +76,7 @@ static int (*default_trust)(int id, X509 *x, int flags) = obj_trust;
  */
 
 static X509_TRUST trstandard[] = {
-{X509_TRUST_ANY, 0, trust_any, "Any", 0, NULL},
+{X509_TRUST_COMPAT, 0, trust_compat, "compatible", 0, NULL},
 {X509_TRUST_SSL_CLIENT, 0, trust_1oidany, "SSL Client", NID_client_auth, NULL},
 {X509_TRUST_SSL_SERVER, 0, trust_1oidany, "SSL Client", NID_server_auth, NULL},
 {X509_TRUST_EMAIL, 0, trust_1oidany, "S/MIME email", NID_email_protect, NULL},
@@ -107,8 +107,8 @@ int X509_check_trust(X509 *x, int id, int flags)
 	X509_TRUST *pt;
 	int idx;
 	if(id == -1) return 1;
-	if(!(idx = X509_TRUST_get_by_id(id)))
-			return default_trust(id, x, flags);
+	idx = X509_TRUST_get_by_id(id);
+	if(idx == -1) return default_trust(id, x, flags);
 	pt = X509_TRUST_get0(idx);
 	return pt->check_trust(pt, x, flags);
 }
@@ -230,6 +230,11 @@ static int trust_1oidany(X509_TRUST *trust, X509 *x, int flags)
 	/* we don't have any trust settings: for compatibility
 	 * we return trusted if it is self signed
 	 */
+	return trust_compat(trust, x, flags);
+}
+
+static int trust_compat(X509_TRUST *trust, X509 *x, int flags)
+{
 	X509_check_purpose(x, -1, 0);
 	if(x->ex_flags & EXFLAG_SS) return X509_TRUST_TRUSTED;
 	else return X509_TRUST_UNTRUSTED;
@@ -257,7 +262,3 @@ static int obj_trust(int id, X509 *x, int flags)
 	return X509_TRUST_UNTRUSTED;
 }
 
-static int trust_any(X509_TRUST *trust, X509 *x, int flags)
-{
-	return X509_TRUST_TRUSTED;
-}

crypto/x509/x509_vfy.c

@@ -771,18 +771,25 @@ int X509_STORE_CTX_purpose_inherit(X509_STORE_CTX *ctx, int def_purpose,
 	if(!purpose) purpose = def_purpose;
 	/* If we have a purpose then check it is valid */
 	if(purpose) {
+		X509_PURPOSE *ptmp;
 		idx = X509_PURPOSE_get_by_id(purpose);
 		if(idx == -1) {
 			X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
 						X509_R_UNKNOWN_PURPOSE_ID);
 			return 0;
 		}
-		/* If trust not set then get from purpose default */
-		if(!trust) {
-			X509_PURPOSE *ptmp;
+		ptmp = X509_PURPOSE_get0(idx);
+		if(ptmp->trust == X509_TRUST_DEFAULT) {
+			idx = X509_PURPOSE_get_by_id(def_purpose);
+			if(idx == -1) {
+				X509err(X509_F_X509_STORE_CTX_PURPOSE_INHERIT,
+						X509_R_UNKNOWN_PURPOSE_ID);
+				return 0;
+			}
 			ptmp = X509_PURPOSE_get0(idx);
-			trust = ptmp->trust;
 		}
+		/* If trust not set then get from purpose default */
+		if(!trust) trust = ptmp->trust;
 	}
 	if(trust) {
 		idx = X509_TRUST_get_by_id(trust);

crypto/x509v3/v3_purp.c

@@ -71,6 +71,7 @@ static int purpose_smime(X509 *x, int ca);
 static int check_purpose_smime_sign(X509_PURPOSE *xp, X509 *x, int ca);
 static int check_purpose_smime_encrypt(X509_PURPOSE *xp, X509 *x, int ca);
 static int check_purpose_crl_sign(X509_PURPOSE *xp, X509 *x, int ca);
+static int no_check(X509_PURPOSE *xp, X509 *x, int ca);
 
 static int xp_cmp(X509_PURPOSE **a, X509_PURPOSE **b);
 static void xptable_free(X509_PURPOSE *p);
@@ -81,7 +82,8 @@ static X509_PURPOSE xstandard[] = {
 	{X509_PURPOSE_NS_SSL_SERVER, X509_TRUST_SSL_SERVER, 0, check_purpose_ns_ssl_server, "Netscape SSL server", "nssslserver", NULL},
 	{X509_PURPOSE_SMIME_SIGN, X509_TRUST_EMAIL, 0, check_purpose_smime_sign, "S/MIME signing", "smimesign", NULL},
 	{X509_PURPOSE_SMIME_ENCRYPT, X509_TRUST_EMAIL, 0, check_purpose_smime_encrypt, "S/MIME encryption", "smimeencrypt", NULL},
-	{X509_PURPOSE_CRL_SIGN, X509_TRUST_ANY, 0, check_purpose_crl_sign, "CRL signing", "crlsign", NULL},
+	{X509_PURPOSE_CRL_SIGN, X509_TRUST_COMPAT, 0, check_purpose_crl_sign, "CRL signing", "crlsign", NULL},
+	{X509_PURPOSE_ANY, X509_TRUST_DEFAULT, 0, no_check, "Any Purpose", "any", NULL},
 };
 
 #define X509_PURPOSE_COUNT (sizeof(xstandard)/sizeof(X509_PURPOSE))
@@ -454,3 +456,8 @@ static int check_purpose_crl_sign(X509_PURPOSE *xp, X509 *x, int ca)
 	if(ku_reject(x, KU_CRL_SIGN)) return 0;
 	return 1;
 }
+
+static int no_check(X509_PURPOSE *xp, X509 *x, int ca)
+{
+	return 1;
+}

crypto/x509v3/x509v3.h

@@ -344,9 +344,10 @@ typedef struct x509_purpose_st {
 #define X509_PURPOSE_SMIME_SIGN		4
 #define X509_PURPOSE_SMIME_ENCRYPT	5
 #define X509_PURPOSE_CRL_SIGN		6
+#define X509_PURPOSE_ANY		7
 
 #define X509_PURPOSE_MIN		1
-#define X509_PURPOSE_MAX		6
+#define X509_PURPOSE_MAX		7
 
 DECLARE_STACK_OF(X509_PURPOSE)