From 00aa0275037565539780376845b4b5b71b5408c2 Mon Sep 17 00:00:00 2001
From: Andreas Steffen <andreas.steffen@strongswan.org>
Date: Wed, 4 Nov 2009 00:03:10 +0100
Subject: [PATCH] implemented parsing of pathLenConstraint

---
 .../credentials/certificates/x509.h           |  9 ++++
 src/libstrongswan/plugins/x509/x509_cert.c    | 47 ++++++++++++++-----
 2 files changed, 45 insertions(+), 11 deletions(-)

diff --git a/src/libstrongswan/credentials/certificates/x509.h b/src/libstrongswan/credentials/certificates/x509.h
index 8af9200ded..6d34195462 100644
--- a/src/libstrongswan/credentials/certificates/x509.h
+++ b/src/libstrongswan/credentials/certificates/x509.h
@@ -24,6 +24,8 @@
 #include <utils/enumerator.h>
 #include <credentials/certificates/certificate.h>
 
+#define NO_PATH_LEN_CONSTRAINT	-1
+
 typedef struct x509_t x509_t;
 typedef enum x509_flag_t x509_flag_t;
 
@@ -91,6 +93,13 @@ struct x509_t {
 	 */
 	chunk_t (*get_authKeyIdentifier)(x509_t *this);
 
+	/**
+	 * Get an optional path length constraint.
+	 *
+	 * @return			pathLenConstraint, -1 if no constraint exists
+	 */
+	int (*get_pathLenConstraint)(x509_t *this);
+
 	/**
 	 * Create an enumerator over all subjectAltNames.
 	 *
diff --git a/src/libstrongswan/plugins/x509/x509_cert.c b/src/libstrongswan/plugins/x509/x509_cert.c
index 353c91e9f5..b10317093b 100644
--- a/src/libstrongswan/plugins/x509/x509_cert.c
+++ b/src/libstrongswan/plugins/x509/x509_cert.c
@@ -145,6 +145,11 @@ struct private_x509_cert_t {
 	 */
 	chunk_t authKeySerialNumber;
 
+	/**
+	 * Path Length Constraint
+	 */
+	int pathLenConstraint;
+
 	/**
 	 * x509 constraints and other flags
 	 */
@@ -185,12 +190,14 @@ static const asn1Object_t basicConstraintsObjects[] = {
 	{ 1,   "end opt",			ASN1_EOC,		ASN1_END  			}, /*  3 */
 	{ 0, "exit",				ASN1_EOC,		ASN1_EXIT  			}
 };
-#define BASIC_CONSTRAINTS_CA	1
+#define BASIC_CONSTRAINTS_CA		1
+#define BASIC_CONSTRAINTS_PATH_LEN	2
 
 /**
  * Extracts the basicConstraints extension
  */
-static bool parse_basicConstraints(chunk_t blob, int level0)
+static void parse_basicConstraints(chunk_t blob, int level0,
+								   private_x509_cert_t *this)
 {
 	asn1_parser_t *parser;
 	chunk_t object;
@@ -202,15 +209,35 @@ static bool parse_basicConstraints(chunk_t blob, int level0)
 
 	while (parser->iterate(parser, &objectID, &object))
 	{
-		if (objectID == BASIC_CONSTRAINTS_CA)
+		switch (objectID)
 		{
-			isCA = object.len && *object.ptr;
-			DBG2("  %s", isCA ? "TRUE" : "FALSE");
+			case BASIC_CONSTRAINTS_CA:
+				isCA = object.len && *object.ptr;
+				DBG2("  %s", isCA ? "TRUE" : "FALSE");
+				if (isCA)
+				{
+					this->flags |= X509_CA;
+				}
+				break;
+			case BASIC_CONSTRAINTS_PATH_LEN:
+				if (isCA)
+				{
+					if (object.len == 0)
+					{
+						this->pathLenConstraint = 0;
+					}
+					else if (object.len == 1)
+					{
+						this->pathLenConstraint = *object.ptr;
+					}
+					/* we ignore path length constraints > 127 */
+				}
+				break;
+			default:
+				break;
 		}
 	}
 	parser->destroy(parser);
-
-	return isCA;
 }
 
 /**
@@ -785,10 +812,7 @@ static bool parse_certificate(private_x509_cert_t *this)
 												this->subjectAltNames);
 						break;
 					case OID_BASIC_CONSTRAINTS:
-						if (parse_basicConstraints(object, level))
-						{
-							this->flags |= X509_CA;
-						}
+						parse_basicConstraints(object, level, this);
 						break;
 					case OID_CRL_DISTRIBUTION_POINTS:
 						parse_crlDistributionPoints(object, level, this);
@@ -1205,6 +1229,7 @@ static private_x509_cert_t* create_empty(void)
 	this->subjectKeyIdentifier = chunk_empty;
 	this->authKeyIdentifier = chunk_empty;
 	this->authKeySerialNumber = chunk_empty;
+	this->pathLenConstraint = NO_PATH_LEN_CONSTRAINT;
 	this->algorithm = 0;
 	this->signature = chunk_empty;
 	this->flags = 0;
-- 
2.47.2