diff --git a/include/osmocom/sim/sim.h b/include/osmocom/sim/sim.h
new file mode 100644
index 0000000..5ad1643
--- /dev/null
+++ b/include/osmocom/sim/sim.h
@@ -0,0 +1,268 @@
+#ifndef _OSMOCOM_SIM_H
+#define _OSMOCOM_SIM_H
+
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/linuxlist.h>
+
+#define APDU_HDR_LEN	5
+
+/* ISO 7816 / 5.3.1 / Figure 3 + Figure 4 */
+enum osim_apdu_case {
+	APDU_CASE_1,
+	APDU_CASE_2,
+	APDU_CASE_2_EXT,
+	APDU_CASE_3,
+	APDU_CASE_3_EXT,
+	APDU_CASE_4,
+	APDU_CASE_4_EXT
+};
+
+struct osim_apdu_cmd_hdr {
+	uint8_t cla;
+	uint8_t ins;
+	uint8_t p1;
+	uint8_t p2;
+	uint8_t p3;
+} __attribute__ ((packed));
+
+#define msgb_apdu_dr(__x)
+
+struct osim_msgb_cb {
+	enum osim_apdu_case apduc;
+	uint16_t lc;
+	uint16_t le;
+	uint16_t sw;
+};
+#define OSIM_MSGB_CB(__msgb)	((struct osim_msgb_cb *)&((__msgb)->cb[0]))
+/*! \brief status word from msgb->cb */
+#define msgb_apdu_case(__x)	OSIM_MSGB_CB(__x)->apduc
+#define msgb_apdu_lc(__x)	OSIM_MSGB_CB(__x)->lc
+#define msgb_apdu_le(__x)	OSIM_MSGB_CB(__x)->le
+#define msgb_apdu_sw(__x)	OSIM_MSGB_CB(__x)->sw
+/*! \brief pointer to the command header of the APDU */
+#define msgb_apdu_h(__x)	((struct osim_apdu_cmd_hdr *)(__x)->l2h)
+
+#define msgb_apdu_dc(__x)	((__x)->l2h + sizeof(struct osim_apdu_cmd_hdr))
+#define msgb_apdu_de(__x)	((__x)->l2h + sizeof(struct osim_apdu_cmd_hdr) + msgb_apdu_lc(__x))
+
+struct osim_file;
+struct osim_file_desc;
+struct osim_decoded_data;
+
+struct osim_file_ops {
+	int (*parse)(struct osim_decoded_data *dd,
+		     const struct osim_file_desc *desc,
+		     int len, uint8_t *data);
+	struct msgb * (*encode)(const struct osim_file *file,
+				const struct osim_decoded_data *decoded);
+};
+
+enum osim_element_type {
+	ELEM_T_NONE,
+	ELEM_T_BOOL,	/*!< a boolean flag */
+	ELEM_T_UINT8,	/*!< unsigned integer */
+	ELEM_T_UINT16,	/*!< unsigned integer */
+	ELEM_T_UINT32,	/*!< unsigned integer */
+	ELEM_T_STRING,	/*!< generic string */
+	ELEM_T_BCD,	/*!< BCD encoded digits */
+	ELEM_T_BYTES,	/*!< BCD encoded digits */
+	ELEM_T_GROUP,	/*!< group container, has siblings */
+};
+
+enum osim_element_repr {
+	ELEM_REPR_NONE,
+	ELEM_REPR_DEC,
+	ELEM_REPR_HEX,
+};
+
+struct osim_decoded_element {
+	struct llist_head list;
+
+	enum osim_element_type type;
+	enum osim_element_repr representation;
+	const char *name;
+
+	unsigned int length;
+	union {
+		uint8_t u8;
+		uint16_t u16;
+		uint32_t u32;
+		uint8_t *buf;
+		struct llist_head siblings;
+	} u;
+};
+
+struct osim_decoded_data {
+	/*! file to which we belong */
+	const struct osim_file *file;
+	/*! list of 'struct decoded_element' */
+	struct llist_head decoded_elements;
+};
+
+
+enum osim_file_type {
+	TYPE_NONE,
+	TYPE_DF,
+	TYPE_ADF,
+	TYPE_EF,
+	TYPE_EF_INT,
+};
+
+enum osim_ef_type {
+	EF_TYPE_TRANSP,
+	EF_TYPE_RECORD_FIXED,
+	EF_TYPE_RECORD_CYCLIC,
+};
+
+#define F_OPTIONAL		0x0001
+
+struct osim_file_desc {
+	struct llist_head list;		/*!< local element in list */
+	struct llist_head child_list;	/*!< list of children EF in DF */
+	struct osim_file_desc *parent;	/*!< parent DF */
+
+	enum osim_file_type type;
+	enum osim_ef_type ef_type;
+
+	uint16_t fid;			/*!< File Identifier */
+	uint8_t sfid;			/*!< Short File IDentifier */
+	const char *df_name;		
+	uint8_t df_name_len;
+
+	const char *short_name;		/*!< Short Name (like EF.ICCID) */
+	const char *long_name;		/*!< Long / description */
+	unsigned int flags;
+
+	struct osim_file_ops ops;
+};
+
+struct osim_file {
+	const struct osim_file_desc *desc;
+
+	struct msgb *encoded_data;
+	struct osim_decoded_data *decoded_data;
+};
+
+#define EF(pfid, pns, pflags, pnl, ptype, pdec, penc)	\
+	{								\
+		.fid		= pfid,					\
+		.type		= TYPE_EF,				\
+		.ef_type	= ptype,				\
+		.short_name	= pns,					\
+		.long_name	= pnl,					\
+		.flags		= pflags,				\
+		.ops 		= { .encode = penc, .parse = pdec },	\
+	}
+
+
+#define EF_TRANSP(fid, ns, flags, nl, dec, enc)	\
+		EF(fid, ns, flags, nl, EF_TYPE_TRANSP, dec, enc)
+#define EF_TRANSP_N(fid, ns, flags, nl) \
+		EF_TRANSP(fid, ns, flags, nl, &default_decode, NULL)
+
+#define EF_CYCLIC(fid, ns, flags, nl, dec, enc)	\
+		EF(fid, ns, flags, nl, EF_TYPE_RECORD_CYCLIC, dec, enc)
+#define EF_CYCLIC_N(fid, ns, flags, nl) \
+		EF_CYCLIC(fid, ns, flags, nl, &default_decode, NULL)
+
+#define EF_LIN_FIX(fid, ns, flags, nl, dec, enc)	\
+		EF(fid, ns, flags, nl, EF_TYPE_RECORD_FIXED, dec, enc)
+#define EF_LIN_FIX_N(fid, ns, flags, nl)	\
+		EF_LIN_FIX(fid, ns, flags, nl, &default_decode, NULL)
+
+struct osim_file_desc *
+osim_file_find_name(struct osim_file_desc *parent, const char *name);
+
+enum osim_card_sw_type {
+	SW_TYPE_NONE,
+	SW_TYPE_STR,
+};
+
+enum osim_card_sw_class {
+	SW_CLS_NONE,
+	SW_CLS_OK,
+	SW_CLS_POSTP,
+	SW_CLS_WARN,
+	SW_CLS_ERROR,
+};
+
+struct osim_card_sw {
+	uint16_t code;
+	uint16_t mask;
+	enum osim_card_sw_type type;
+	enum osim_card_sw_class class;
+	union {
+		const char *str;
+	} u;
+};
+
+#define OSIM_CARD_SW_LAST	{			\
+	.code = 0, .mask = 0, .type = SW_TYPE_NONE,	\
+	.class = SW_CLS_NONE, .u.str = NULL		\
+}
+
+struct osim_card_profile {
+	const char *name;
+	struct osim_file_desc *mf;
+	struct osim_card_sw **sws;
+};
+
+extern const struct tlv_definition ts102221_fcp_tlv_def;
+const struct value_string ts102221_fcp_vals[14];
+
+/* 11.1.1.3 */
+enum ts102221_fcp_tag {
+	UICC_FCP_T_FCP		= 0x62,
+	UICC_FCP_T_FILE_SIZE	= 0x80,
+	UICC_FCP_T_TOT_F_SIZE	= 0x81,
+	UICC_FCP_T_FILE_DESC	= 0x82,
+	UICC_FCP_T_FILE_ID	= 0x83,
+	UICC_FCP_T_DF_NAME	= 0x84,
+	UICC_FCP_T_SFID		= 0x88,
+	UICC_FCP_T_LIFEC_STS	= 0x8A,
+	UICC_FCP_T_SEC_ATTR_REFEXP= 0x8B,
+	UICC_FCP_T_SEC_ATTR_COMP= 0x8C,
+	UICC_FCP_T_PROPRIETARY	= 0xA5,
+	UICC_FCP_T_SEC_ATTR_EXP	= 0xAB,
+	UICC_FCP_T_PIN_STS_DO	= 0xC6,
+};
+
+struct msgb *osim_new_apdumsg(uint8_t cla, uint8_t ins, uint8_t p1,
+			      uint8_t p2, uint16_t lc, uint16_t le);
+
+struct osim_reader_ops;
+
+struct osim_reader_hdl {
+	/*! \brief member in global list of readers */
+	struct llist_head list;
+	struct osim_reader_ops *ops;
+	void *priv;
+	/*! \brief current card, if any */
+	struct osim_card_hdl *card;
+};
+
+struct osim_card_hdl {
+	/*! \brief member in global list of cards */
+	struct llist_head list;
+	/*! \brief reader through which card is accessed */
+	struct osim_reader_hdl *reader;
+	/*! \brief card profile */
+	struct osim_card_profile *prof;
+
+	/*! \brief list of channels for this card */
+	struct llist_head channels;
+};
+
+struct osim_chan_hdl {
+	/*! \brief linked to card->channels */
+	struct llist_head list;
+	/*! \brief card to which this channel belongs */
+	struct osim_card_hdl *card;
+	const struct osim_file_desc *cwd;
+};
+
+/* reader.c */
+int osim_transceive_apdu(struct osim_chan_hdl *st, struct msgb *amsg);
+struct osim_reader_hdl *osim_reader_open(int idx, const char *name);
+struct osim_card_hdl *osim_card_open(struct osim_reader_hdl *rh);
+#endif /* _OSMOCOM_SIM_H */