s4: auth: gensec: asn1 fixes - check all returns.

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>

1 files changed, 22 insertions, 19 deletions

diff --git a/source4/auth/gensec/gensec_krb5.c b/source4/auth/gensec/gensec_krb5.c
index 237a2633c92..c34c43425e4 100644
--- a/source4/auth/gensec/gensec_krb5.c
+++ b/source4/auth/gensec/gensec_krb5.c
@@ -403,30 +403,31 @@ static NTSTATUS gensec_fake_gssapi_krb5_client_start(struct gensec_security *gen
 static DATA_BLOB gensec_gssapi_gen_krb5_wrap(TALLOC_CTX *mem_ctx, const DATA_BLOB *ticket, const uint8_t tok_id[2])
 {
 	struct asn1_data *data;
-	DATA_BLOB ret;
+	DATA_BLOB ret = data_blob_null;
 
 	data = asn1_init(mem_ctx);
 	if (!data || !ticket->data) {
-		return data_blob(NULL,0);
+		return ret;
 	}
 
-	asn1_push_tag(data, ASN1_APPLICATION(0));
-	asn1_write_OID(data, GENSEC_OID_KERBEROS5);
+	if (!asn1_push_tag(data, ASN1_APPLICATION(0))) goto err;
+	if (!asn1_write_OID(data, GENSEC_OID_KERBEROS5)) goto err;
 
-	asn1_write(data, tok_id, 2);
-	asn1_write(data, ticket->data, ticket->length);
-	asn1_pop_tag(data);
+	if (!asn1_write(data, tok_id, 2)) goto err;
+	if (!asn1_write(data, ticket->data, ticket->length)) goto err;
+	if (!asn1_pop_tag(data)) goto err;
 
-	if (data->has_error) {
-		DEBUG(1,("Failed to build krb5 wrapper at offset %d\n", (int)data->ofs));
-		asn1_free(data);
-		return data_blob(NULL,0);
-	}
 
 	ret = data_blob_talloc(mem_ctx, data->data, data->length);
 	asn1_free(data);
 
 	return ret;
+
+  err:
+
+	DEBUG(1,("Failed to build krb5 wrapper at offset %d\n", (int)data->ofs));
+	asn1_free(data);
+	return ret;
 }
 
 /*
@@ -434,7 +435,7 @@ static DATA_BLOB gensec_gssapi_gen_krb5_wrap(TALLOC_CTX *mem_ctx, const DATA_BLO
 */
 static bool gensec_gssapi_parse_krb5_wrap(TALLOC_CTX *mem_ctx, const DATA_BLOB *blob, DATA_BLOB *ticket, uint8_t tok_id[2])
 {
-	bool ret;
+	bool ret = false;
 	struct asn1_data *data = asn1_init(mem_ctx);
 	int data_remaining;
 
@@ -442,25 +443,27 @@ static bool gensec_gssapi_parse_krb5_wrap(TALLOC_CTX *mem_ctx, const DATA_BLOB *
 		return false;
 	}
 
-	asn1_load(data, *blob);
-	asn1_start_tag(data, ASN1_APPLICATION(0));
-	asn1_check_OID(data, GENSEC_OID_KERBEROS5);
+	if (!asn1_load(data, *blob)) goto err;
+	if (!asn1_start_tag(data, ASN1_APPLICATION(0))) goto err;
+	if (!asn1_check_OID(data, GENSEC_OID_KERBEROS5)) goto err;
 
 	data_remaining = asn1_tag_remaining(data);
 
 	if (data_remaining < 3) {
 		data->has_error = true;
 	} else {
-		asn1_read(data, tok_id, 2);
+		if (!asn1_read(data, tok_id, 2)) goto err;
 		data_remaining -= 2;
 		*ticket = data_blob_talloc(mem_ctx, NULL, data_remaining);
-		asn1_read(data, ticket->data, ticket->length);
+		if (!asn1_read(data, ticket->data, ticket->length)) goto err;
 	}
 
-	asn1_end_tag(data);
+	if (!asn1_end_tag(data)) goto err;
 
 	ret = !data->has_error;
 
+  err:
+
 	asn1_free(data);
 
 	return ret;