diff --git a/src/s1ap/asn1c/asnGenFiles/per_decoder.h b/src/s1ap/asn1c/asnGenFiles/per_decoder.h
new file mode 100644
index 0000000..eea474a
--- /dev/null
+++ b/src/s1ap/asn1c/asnGenFiles/per_decoder.h
@@ -0,0 +1,82 @@
+/*-
+ * Copyright (c) 2005-2017 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+#ifndef	_PER_DECODER_H_
+#define	_PER_DECODER_H_
+
+#include <asn_application.h>
+#include <per_support.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct asn_TYPE_descriptor_s;	/* Forward declaration */
+
+/*
+ * Unaligned PER decoder of a "complete encoding" as per X.691 (08/2015) #11.1.
+ * On success, this call always returns (.consumed >= 1), as per #11.1.3.
+ */
+asn_dec_rval_t uper_decode_complete(
+    const struct asn_codec_ctx_s *opt_codec_ctx,
+    const struct asn_TYPE_descriptor_s *type_descriptor, /* Type to decode */
+    void **struct_ptr,  /* Pointer to a target structure's pointer */
+    const void *buffer, /* Data to be decoded */
+    size_t size         /* Size of data buffer */
+);
+
+/*
+ * Unaligned PER decoder of any ASN.1 type. May be invoked by the application.
+ * WARNING: This call returns the number of BITS read from the stream. Beware.
+ */
+asn_dec_rval_t uper_decode(
+    const struct asn_codec_ctx_s *opt_codec_ctx,
+    const struct asn_TYPE_descriptor_s *type_descriptor, /* Type to decode */
+    void **struct_ptr,  /* Pointer to a target structure's pointer */
+    const void *buffer, /* Data to be decoded */
+    size_t size,        /* Size of the input data buffer, in bytes */
+    int skip_bits,      /* Number of unused leading bits, 0..7 */
+    int unused_bits     /* Number of unused tailing bits, 0..7 */
+);
+
+/*
+ * Aligned PER decoder of a "complete encoding" as per X.691#10.1.
+ * On success, this call always returns (.consumed >= 1), in BITS, as per X.691#10.1.3.
+ */
+asn_dec_rval_t aper_decode_complete(
+       const struct asn_codec_ctx_s *opt_codec_ctx,
+       const struct asn_TYPE_descriptor_s *type_descriptor,	/* Type to decode */
+       void **struct_ptr,	/* Pointer to a target structure's pointer */
+       const void *buffer,	/* Data to be decoded */
+       size_t size		/* Size of data buffer */
+									);
+
+/*
+ * Aligned PER decoder of any ASN.1 type. May be invoked by the application.
+ * WARNING: This call returns the number of BITS read from the stream. Beware.
+ */
+asn_dec_rval_t aper_decode(
+      const struct asn_codec_ctx_s *opt_codec_ctx,
+      const struct asn_TYPE_descriptor_s *type_descriptor,	/* Type to decode */
+      void **struct_ptr,	/* Pointer to a target structure's pointer */
+      const void *buffer,	/* Data to be decoded */
+      size_t size,		/* Size of data buffer */
+      int skip_bits,		/* Number of unused leading bits, 0..7 */
+      int unused_bits		/* Number of unused tailing bits, 0..7 */
+      );
+
+/*
+ * Type of the type-specific PER decoder function.
+ */
+typedef asn_dec_rval_t(per_type_decoder_f)(
+    const asn_codec_ctx_t *opt_codec_ctx,
+    const struct asn_TYPE_descriptor_s *type_descriptor,
+    const asn_per_constraints_t *constraints, void **struct_ptr,
+    asn_per_data_t *per_data);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	/* _PER_DECODER_H_ */