Osmocom Authentication Protocol

The Osmocom Authentication Protocol (OAP) is a way to use the 3GPP AKA (Authentication and Key Agreement) as cryptographic authentication mechanism in other protocols that don't provide cryptographic authentication. More...

Files
file	include/osmocom/gsm/oap.h
file	src/gsm/oap.c
	Osmocom Authentication Protocol.

Data Structures
struct	osmo_oap_message
	Parsed/decoded OAP protocol message. More...

Enumerations
enum	osmo_oap_iei {   OAP_CAUSE_IE = 0x02 ,   OAP_RAND_IE = 0x20 ,   OAP_AUTN_IE = 0x23 ,   OAP_XRES_IE = 0x24 ,   OAP_AUTS_IE = 0x25 ,   OAP_CLIENT_ID_IE = 0x30 }
	Information Element Identifiers for OAP IEs. More...
enum	osmo_oap_message_type {   OAP_MSGT_REGISTER_REQUEST = 0b00000100 ,   OAP_MSGT_REGISTER_ERROR = 0b00000101 ,   OAP_MSGT_REGISTER_RESULT = 0b00000110 ,   OAP_MSGT_CHALLENGE_REQUEST = 0b00001000 ,   OAP_MSGT_CHALLENGE_ERROR = 0b00001001 ,   OAP_MSGT_CHALLENGE_RESULT = 0b00001010 ,   OAP_MSGT_SYNC_REQUEST = 0b00001100 ,   OAP_MSGT_SYNC_ERROR = 0b00001101 ,   OAP_MSGT_SYNC_RESULT = 0b00001110 }
	OAP message types. More...

Functions
int	osmo_oap_decode (struct osmo_oap_message *oap_msg, const uint8_t *const_data, size_t data_len)
	Decode OAP message data.
void	osmo_oap_encode (struct msgb *msg, const struct osmo_oap_message *oap_msg)
	Compose OAP message data.

Detailed Description

The Osmocom Authentication Protocol (OAP) is a way to use the 3GPP AKA (Authentication and Key Agreement) as cryptographic authentication mechanism in other protocols that don't provide cryptographic authentication.

Enumeration Type Documentation

osmo_oap_iei

enum osmo_oap_iei

Information Element Identifiers for OAP IEs.

They match osmo_gsup_iei (so far).

Enumerator
OAP_CAUSE_IE
OAP_RAND_IE
OAP_AUTN_IE
OAP_XRES_IE
OAP_AUTS_IE
OAP_CLIENT_ID_IE

osmo_oap_message_type

enum osmo_oap_message_type

OAP message types.

Enumerator
OAP_MSGT_REGISTER_REQUEST
OAP_MSGT_REGISTER_ERROR
OAP_MSGT_REGISTER_RESULT
OAP_MSGT_CHALLENGE_REQUEST
OAP_MSGT_CHALLENGE_ERROR
OAP_MSGT_CHALLENGE_RESULT
OAP_MSGT_SYNC_REQUEST
OAP_MSGT_SYNC_ERROR
OAP_MSGT_SYNC_RESULT

Function Documentation

osmo_oap_decode()

int osmo_oap_decode	(	struct osmo_oap_message *	oap_msg,
		const uint8_t *	const_data,
		size_t	data_len )

Decode OAP message data.

Parameters

[out]	oap_msg	Parsed data is written to this instance.
[in]	data	Pointer to the data buffer containing the OAP message.
[in]	data_len	Length of the OAP message data.

Returns

0 on success, a negative cause value on failure.

References osmo_oap_message::autn, osmo_oap_message::autn_present, osmo_oap_message::auts, osmo_oap_message::auts_present, osmo_oap_message::cause, osmo_oap_message::client_id, GMM_CAUSE_INV_MAND_INFO, GMM_CAUSE_PROTO_ERR_UNSPEC, osmo_oap_message::message_type, OAP_AUTN_IE, OAP_AUTS_IE, OAP_CAUSE_IE, OAP_CLIENT_ID_IE, OAP_RAND_IE, OAP_XRES_IE, osmo_oap_decode(), osmo_shift_tlv(), osmo_shift_v_fixed(), osmo_oap_message::rand, osmo_oap_message::rand_present, osmo_oap_message::xres, and osmo_oap_message::xres_present.

Referenced by osmo_oap_client_handle(), and osmo_oap_decode().

osmo_oap_encode()

void osmo_oap_encode	(	struct msgb *	msg,
		const struct osmo_oap_message *	oap_msg )

Compose OAP message data.

Parameters

[out]	msg	OAP message data is appended to this message buffer.
[in]	oap_msg	Elements to encode in the message data.

References osmo_oap_message::autn, osmo_oap_message::autn_present, osmo_oap_message::auts, osmo_oap_message::auts_present, osmo_oap_message::cause, osmo_oap_message::client_id, osmo_oap_message::message_type, msg, msgb_tlv_put(), msgb_v_put(), OAP_AUTN_IE, OAP_AUTS_IE, OAP_CAUSE_IE, OAP_CLIENT_ID_IE, OAP_RAND_IE, OAP_XRES_IE, osmo_oap_encode(), osmo_oap_message::rand, osmo_oap_message::rand_present, osmo_oap_message::xres, and osmo_oap_message::xres_present.

Referenced by osmo_oap_client_encoded(), and osmo_oap_encode().