diff --git a/include/osmocom/rspro/asn_codecs.h b/include/osmocom/rspro/asn_codecs.h
new file mode 100644
index 0000000..e560014
--- /dev/null
+++ b/include/osmocom/rspro/asn_codecs.h
@@ -0,0 +1,109 @@
+/*-
+ * Copyright (c) 2003, 2004, 2005 Lev Walkin <vlm@lionet.info>.
+ * All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+#ifndef	_ASN_CODECS_H_
+#define	_ASN_CODECS_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct asn_TYPE_descriptor_s;	/* Forward declaration */
+
+/*
+ * This structure defines a set of parameters that may be passed
+ * to every ASN.1 encoder or decoder function.
+ * WARNING: if max_stack_size member is set, and you are calling the
+ *   function pointers of the asn_TYPE_descriptor_t directly,
+ *   this structure must be ALLOCATED ON THE STACK!
+ *   If you can't always satisfy this requirement, use ber_decode(),
+ *   xer_decode() and uper_decode() functions instead.
+ */
+typedef struct asn_codec_ctx_s {
+	/*
+	 * Limit the decoder routines to use no (much) more stack than a given
+	 * number of bytes. Most of decoders are stack-based, and this
+	 * would protect against stack overflows if the number of nested
+	 * encodings is high.
+	 * The OCTET STRING, BIT STRING and ANY BER decoders are heap-based,
+	 * and are safe from this kind of overflow.
+	 * A value from getrlimit(RLIMIT_STACK) may be used to initialize
+	 * this variable. Be careful in multithreaded environments, as the
+	 * stack size is rather limited.
+	 */
+	size_t  max_stack_size; /* 0 disables stack bounds checking */
+} asn_codec_ctx_t;
+
+/*
+ * Type of the return value of the encoding functions (der_encode, xer_encode).
+ */
+typedef struct asn_enc_rval_s {
+	/*
+	 * Number of bytes encoded.
+	 * -1 indicates failure to encode the structure.
+	 * In this case, the members below this one are meaningful.
+	 */
+	ssize_t encoded;
+
+	/*
+	 * Members meaningful when (encoded == -1), for post mortem analysis.
+	 */
+
+	/* Type which cannot be encoded */
+	struct asn_TYPE_descriptor_s *failed_type;
+
+	/* Pointer to the structure of that type */
+	void *structure_ptr;
+} asn_enc_rval_t;
+#define	_ASN_ENCODE_FAILED do {					\
+	asn_enc_rval_t tmp_error;				\
+	tmp_error.encoded = -1;					\
+	tmp_error.failed_type = td;				\
+	tmp_error.structure_ptr = sptr;				\
+	ASN_DEBUG("Failed to encode element %s", td ? td->name : "");	\
+	return tmp_error;					\
+} while(0)
+#define	_ASN_ENCODED_OK(rval) do {				\
+	rval.structure_ptr = 0;					\
+	rval.failed_type = 0;					\
+	return rval;						\
+} while(0)
+
+/*
+ * Type of the return value of the decoding functions (ber_decode, xer_decode)
+ * 
+ * Please note that the number of consumed bytes is ALWAYS meaningful,
+ * even if code==RC_FAIL. This is to indicate the number of successfully
+ * decoded bytes, hence providing a possibility to fail with more diagnostics
+ * (i.e., print the offending remainder of the buffer).
+ */
+enum asn_dec_rval_code_e {
+	RC_OK,		/* Decoded successfully */
+	RC_WMORE,	/* More data expected, call again */
+	RC_FAIL		/* Failure to decode data */
+};
+typedef struct asn_dec_rval_s {
+	enum asn_dec_rval_code_e code;	/* Result code */
+	size_t consumed;		/* Number of bytes consumed */
+} asn_dec_rval_t;
+#define	_ASN_DECODE_FAILED do {					\
+	asn_dec_rval_t tmp_error;				\
+	tmp_error.code = RC_FAIL;				\
+	tmp_error.consumed = 0;					\
+	ASN_DEBUG("Failed to decode element %s", td ? td->name : "");	\
+	return tmp_error;					\
+} while(0)
+#define	_ASN_DECODE_STARVED do {				\
+	asn_dec_rval_t tmp_error;				\
+	tmp_error.code = RC_WMORE;				\
+	tmp_error.consumed = 0;					\
+	return tmp_error;					\
+} while(0)
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	/* _ASN_CODECS_H_ */