spnego: Support ASN.1 BIT STRING and use it in SPNEGO.

Signed-off-by: Günther Deschner <gd@samba.org>

2 files changed, 44 insertions, 0 deletions

diff --git a/lib/util/asn1.c b/lib/util/asn1.c
index 317ee1314c..70c2c57450 100644
--- a/lib/util/asn1.c
+++ b/lib/util/asn1.c
@@ -205,6 +205,15 @@ bool asn1_write_Integer(struct asn1_data *data, int i)
 	return asn1_pop_tag(data);
 }
 
+/* write a BIT STRING */
+bool asn1_write_BitString(struct asn1_data *data, const void *p, size_t length, uint8_t padding)
+{
+	if (!asn1_push_tag(data, ASN1_BIT_STRING)) return false;
+	if (!asn1_write_uint8(data, padding)) return false;
+	if (!asn1_write(data, p, length)) return false;
+	return asn1_pop_tag(data);
+}
+
 bool ber_write_OID_String(DATA_BLOB *blob, const char *OID)
 {
 	uint_t v, v2;
@@ -727,6 +736,39 @@ bool asn1_read_Integer(struct asn1_data *data, int *i)
 	return asn1_end_tag(data);	
 }
 
+/* read a BIT STRING */
+bool asn1_read_BitString(struct asn1_data *data, TALLOC_CTX *mem_ctx, DATA_BLOB *blob, uint8_t *padding)
+{
+	int len;
+	ZERO_STRUCTP(blob);
+	if (!asn1_start_tag(data, ASN1_BIT_STRING)) return false;
+	len = asn1_tag_remaining(data);
+	if (len < 0) {
+		data->has_error = true;
+		return false;
+	}
+	if (!asn1_read_uint8(data, padding)) return false;
+
+	*blob = data_blob_talloc(mem_ctx, NULL, len);
+	if (!blob->data) {
+		data->has_error = true;
+		return false;
+	}
+	if (asn1_read(data, blob->data, len - 1)) {
+		blob->length--;
+		blob->data[len] = 0;
+		asn1_end_tag(data);
+	}
+
+	if (data->has_error) {
+		data_blob_free(blob);
+		*blob = data_blob_null;
+		*padding = 0;
+		return false;
+	}
+	return true;
+}
+
 /* read an integer */
 bool asn1_read_enumerated(struct asn1_data *data, int *v)
 {
diff --git a/lib/util/asn1.h b/lib/util/asn1.h
index 4c6624056e..9abae50d64 100644
--- a/lib/util/asn1.h
+++ b/lib/util/asn1.h
@@ -60,6 +60,7 @@ bool asn1_push_tag(struct asn1_data *data, uint8_t tag);
 bool asn1_pop_tag(struct asn1_data *data);
 bool asn1_write_implicit_Integer(struct asn1_data *data, int i);
 bool asn1_write_Integer(struct asn1_data *data, int i);
+bool asn1_write_BitString(struct asn1_data *data, const void *p, size_t length, uint8_t padding);
 bool ber_write_OID_String(DATA_BLOB *blob, const char *OID);
 bool asn1_write_OID(struct asn1_data *data, const char *OID);
 bool asn1_write_OctetString(struct asn1_data *data, const void *p, size_t length);
@@ -90,6 +91,7 @@ bool asn1_read_OctetString(struct asn1_data *data, TALLOC_CTX *mem_ctx, DATA_BLO
 bool asn1_read_ContextSimple(struct asn1_data *data, uint8_t num, DATA_BLOB *blob);
 bool asn1_read_implicit_Integer(struct asn1_data *data, int *i);
 bool asn1_read_Integer(struct asn1_data *data, int *i);
+bool asn1_read_BitString(struct asn1_data *data, TALLOC_CTX *mem_ctx, DATA_BLOB *blob, uint8_t *padding);
 bool asn1_read_enumerated(struct asn1_data *data, int *v);
 bool asn1_check_enumerated(struct asn1_data *data, int v);
 bool asn1_write_enumerated(struct asn1_data *data, uint8_t v);