tls_schannel.c File Reference

WPA Supplicant / SSL/TLS interface functions for Microsoft Schannel. More...

#include "includes.h"
#include <windows.h>
#include <wincrypt.h>
#include <schannel.h>
#include <security.h>
#include <sspi.h>
#include "common.h"
#include "tls.h"

Include dependency graph for tls_schannel.c:

Go to the source code of this file.

Data Structures
struct	tls_global
struct	tls_connection
struct	_SecPkgContext_EapKeyBlock
Defines
#define	SECURITY_WIN32
#define	SECPKG_ATTR_EAP_KEY_BLOCK   0x5b
Typedefs
typedef struct _SecPkgContext_EapKeyBlock	SecPkgContext_EapKeyBlock
typedef struct _SecPkgContext_EapKeyBlock *	PSecPkgContext_EapKeyBlock
Functions
void *	tls_init (const struct tls_config *conf)
	Initialize TLS library.
void	tls_deinit (void *ssl_ctx)
	Deinitialize TLS library.
int	tls_get_errors (void *ssl_ctx)
	Process pending errors.
struct tls_connection *	tls_connection_init (void *ssl_ctx)
	Initialize a new TLS connection.
void	tls_connection_deinit (void *ssl_ctx, struct tls_connection *conn)
	Free TLS connection data.
int	tls_connection_established (void *ssl_ctx, struct tls_connection *conn)
	Has the TLS connection been completed?
int	tls_connection_shutdown (void *ssl_ctx, struct tls_connection *conn)
	Shutdown TLS connection.
int	tls_global_set_params (void *tls_ctx, const struct tls_connection_params *params)
	Set TLS parameters for all TLS connection.
int	tls_global_set_verify (void *ssl_ctx, int check_crl)
	Set global certificate verification options.
int	tls_connection_set_verify (void *ssl_ctx, struct tls_connection *conn, int verify_peer)
	Set certificate verification options.
int	tls_connection_get_keys (void *ssl_ctx, struct tls_connection *conn, struct tls_keys *keys)
	Get master key and random data from TLS connection.
int	tls_connection_prf (void *tls_ctx, struct tls_connection *conn, const char *label, int server_random_first, u8 *out, size_t out_len)
	Use TLS-PRF to derive keying material.
u8 *	tls_connection_handshake (void *ssl_ctx, struct tls_connection *conn, const u8 *in_data, size_t in_len, size_t *out_len, u8 **appl_data, size_t *appl_data_len)
	Process TLS handshake (client side).
u8 *	tls_connection_server_handshake (void *ssl_ctx, struct tls_connection *conn, const u8 *in_data, size_t in_len, size_t *out_len)
	Process TLS handshake (server side).
int	tls_connection_encrypt (void *ssl_ctx, struct tls_connection *conn, const u8 *in_data, size_t in_len, u8 *out_data, size_t out_len)
	Encrypt data into TLS tunnel.
int	tls_connection_decrypt (void *ssl_ctx, struct tls_connection *conn, const u8 *in_data, size_t in_len, u8 *out_data, size_t out_len)
	Decrypt data from TLS tunnel.
int	tls_connection_resumed (void *ssl_ctx, struct tls_connection *conn)
	Was session resumption used.
int	tls_connection_set_cipher_list (void *tls_ctx, struct tls_connection *conn, u8 *ciphers)
	Configure acceptable cipher suites.
int	tls_get_cipher (void *ssl_ctx, struct tls_connection *conn, char *buf, size_t buflen)
	Get current cipher name.
int	tls_connection_enable_workaround (void *ssl_ctx, struct tls_connection *conn)
	Enable TLS workaround options.
int	tls_connection_client_hello_ext (void *ssl_ctx, struct tls_connection *conn, int ext_type, const u8 *data, size_t data_len)
	Set TLS extension for ClientHello.
int	tls_connection_get_failed (void *ssl_ctx, struct tls_connection *conn)
	Get connection failure status.
int	tls_connection_get_read_alerts (void *ssl_ctx, struct tls_connection *conn)
	Get connection read alert status.
int	tls_connection_get_write_alerts (void *ssl_ctx, struct tls_connection *conn)
	Get connection write alert status.
int	tls_connection_set_params (void *tls_ctx, struct tls_connection *conn, const struct tls_connection_params *params)
	Set TLS connection parameters.
unsigned int	tls_capabilities (void *tls_ctx)
	Get supported TLS capabilities.
int	tls_connection_set_ia (void *tls_ctx, struct tls_connection *conn, int tls_ia)
	Set TLS/IA parameters.
int	tls_connection_ia_send_phase_finished (void *tls_ctx, struct tls_connection *conn, int final, u8 *out_data, size_t out_len)
	Send a TLS/IA PhaseFinished message.
int	tls_connection_ia_final_phase_finished (void *tls_ctx, struct tls_connection *conn)
	Has final phase been completed.
int	tls_connection_ia_permute_inner_secret (void *tls_ctx, struct tls_connection *conn, const u8 *key, size_t key_len)
	Permute TLS/IA inner secret.

---

Detailed Description

WPA Supplicant / SSL/TLS interface functions for Microsoft Schannel.

Copyright

Copyright (c) 2005, Jouni Malinen <j@w1.fi>

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2 as published by the Free Software Foundation.

Alternatively, this software may be distributed under the terms of BSD license.

See README and COPYING for more details.

Definition in file tls_schannel.c.

---

Function Documentation

unsigned int tls_capabilities

(

void *

tls_ctx

)

Get supported TLS capabilities.

Parameters:

tls_ctx

TLS context data from tls_init()

Returns:

Bit field of supported TLS capabilities (TLS_CAPABILITY_*)

Definition at line 756 of file tls_schannel.c.

int tls_connection_client_hello_ext	(	void *	tls_ctx,
		struct tls_connection *	conn,
		int	ext_type,
		const u8 *	data,
		size_t	data_len
	)

Set TLS extension for ClientHello.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	ext_type	Extension type
	data	Extension payload (NULL to remove extension)
	data_len	Extension payload length

Returns:

0 on success, -1 on failure

Definition at line 679 of file tls_schannel.c.

int tls_connection_decrypt	(	void *	tls_ctx,
		struct tls_connection *	conn,
		const u8 *	in_data,
		size_t	in_len,
		u8 *	out_data,
		size_t	out_len
	)

Decrypt data from TLS tunnel.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	in_data	Pointer to input buffer (encrypted TLS data)
	in_len	Input buffer length
	out_data	Pointer to output buffer (decrypted data from TLS tunnel)
	out_len	Maximum out_data length

Returns:

Number of bytes written to out_data, -1 on failure

This function is used after TLS handshake has been completed successfully to receive data from the encrypted tunnel.

Definition at line 571 of file tls_schannel.c.

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void tls_connection_deinit	(	void *	tls_ctx,
		struct tls_connection *	conn
	)

Free TLS connection data.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()

Release all resources allocated for TLS connection.

Definition at line 136 of file tls_schannel.c.

int tls_connection_enable_workaround	(	void *	tls_ctx,
		struct tls_connection *	conn
	)

Enable TLS workaround options.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()

Returns:

0 on success, -1 on failure

This function is used to enable connection-specific workaround options for buffer SSL/TLS implementations.

Definition at line 672 of file tls_schannel.c.

int tls_connection_encrypt	(	void *	tls_ctx,
		struct tls_connection *	conn,
		const u8 *	in_data,
		size_t	in_len,
		u8 *	out_data,
		size_t	out_len
	)

Encrypt data into TLS tunnel.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	in_data	Pointer to plaintext data to be encrypted
	in_len	Input buffer length
	out_data	Pointer to output buffer (encrypted TLS data)
	out_len	Maximum out_data length

Returns:

Number of bytes written to out_data, -1 on failure

This function is used after TLS handshake has been completed successfully to send data in the encrypted tunnel.

Definition at line 483 of file tls_schannel.c.

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int tls_connection_established	(	void *	tls_ctx,
		struct tls_connection *	conn
	)

Has the TLS connection been completed?

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()

Returns:

1 if TLS connection has been completed, 0 if not.

Definition at line 145 of file tls_schannel.c.

int tls_connection_get_failed	(	void *	tls_ctx,
		struct tls_connection *	conn
	)

Get connection failure status.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()

Returns >0 if connection has failed, 0 if not.

Definition at line 687 of file tls_schannel.c.

int tls_connection_get_keys	(	void *	tls_ctx,
		struct tls_connection *	conn,
		struct tls_keys *	keys
	)

Get master key and random data from TLS connection.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	keys	Structure of key/random data (filled on success)

Returns:

0 on success, -1 on failure

Definition at line 187 of file tls_schannel.c.

int tls_connection_get_read_alerts	(	void *	tls_ctx,
		struct tls_connection *	conn
	)

Get connection read alert status.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()

Returns:

Number of times a fatal read (remote end reported error) has happened during this connection.

Definition at line 695 of file tls_schannel.c.

int tls_connection_get_write_alerts	(	void *	tls_ctx,
		struct tls_connection *	conn
	)

Get connection write alert status.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()

Returns:

Number of times a fatal write (locally detected error) has happened during this connection.

Definition at line 703 of file tls_schannel.c.

u8* tls_connection_handshake	(	void *	tls_ctx,
		struct tls_connection *	conn,
		const u8 *	in_data,
		size_t	in_len,
		size_t *	out_len,
		u8 **	appl_data,
		size_t *	appl_data_len
	)

Process TLS handshake (client side).

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	in_data	Input data from TLS peer
	in_len	Input data length
	out_len	Length of the output buffer.
	appl_data	Pointer to application data pointer, or NULL if dropped
	appl_data_len	Pointer to variable that is set to appl_data length

Returns:

Pointer to output data, NULL on failure

Caller is responsible for freeing returned output data. If the final handshake message includes application data, this is decrypted and appl_data (if not NULL) is set to point this data. Caller is responsible for freeing appl_data.

This function is used during TLS handshake. The first call is done with in_data == NULL and the library is expected to return ClientHello packet. This packet is then send to the server and a response from server is given to TLS library by calling this function again with in_data pointing to the TLS message from the server.

If the TLS handshake fails, this function may return NULL. However, if the TLS library has a TLS alert to send out, that should be returned as the output data. In this case, tls_connection_get_failed() must return failure (> 0).

tls_connection_established() should return 1 once the TLS handshake has been completed successfully.

Definition at line 320 of file tls_schannel.c.

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int tls_connection_ia_final_phase_finished	(	void *	tls_ctx,
		struct tls_connection *	conn
	)

Has final phase been completed.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()

Returns:

1 if valid FinalPhaseFinished has been received, 0 if not, or -1 on failure

Definition at line 778 of file tls_schannel.c.

int tls_connection_ia_permute_inner_secret	(	void *	tls_ctx,
		struct tls_connection *	conn,
		const u8 *	key,
		size_t	key_len
	)

Permute TLS/IA inner secret.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	key	Session key material (session_key vectors with 2-octet length), or NULL if no session key was generating in the current phase
	key_len	Length of session key material

Returns:

0 on success, -1 on failure

Definition at line 785 of file tls_schannel.c.

int tls_connection_ia_send_phase_finished	(	void *	tls_ctx,
		struct tls_connection *	conn,
		int	final,
		u8 *	out_data,
		size_t	out_len
	)

Send a TLS/IA PhaseFinished message.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	final	1 = FinalPhaseFinished, 0 = IntermediatePhaseFinished
	out_data	Pointer to output buffer (encrypted TLS/IA data)
	out_len	Maximum out_data length

Returns:

Number of bytes written to out_data on success, -1 on failure

This function is used to send the TLS/IA end phase message, e.g., when the EAP server completes EAP-TTLSv1.

Definition at line 769 of file tls_schannel.c.

struct tls_connection* tls_connection_init

(

void *

tls_ctx

)

[read]

Initialize a new TLS connection.

Parameters:

tls_ctx

TLS context data from tls_init()

Returns:

Connection context data, conn for other function calls

Definition at line 123 of file tls_schannel.c.

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int tls_connection_prf	(	void *	tls_ctx,
		struct tls_connection *	conn,
		const char *	label,
		int	server_random_first,
		u8 *	out,
		size_t	out_len
	)

Use TLS-PRF to derive keying material.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	label	Label (e.g., description of the key) for PRF
	server_random_first	seed is 0 = client_random|server_random, 1 = server_random|client_random
	out	Buffer for output data from TLS-PRF
	out_len	Length of the output buffer

Returns:

0 on success, -1 on failure

This function is optional to implement if tls_connection_get_keys() provides access to master secret and server/client random values. If these values are not exported from the TLS library, tls_connection_prf() is required so that further keying material can be derived from the master secret. If not implemented, the function will still need to be defined, but it can just return -1. Example implementation of this function is in tls_prf() function when it is called with seed set to client_random|server_random (or server_random|client_random).

Definition at line 195 of file tls_schannel.c.

int tls_connection_resumed	(	void *	tls_ctx,
		struct tls_connection *	conn
	)

Was session resumption used.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()

Returns:

1 if current session used session resumption, 0 if not

Definition at line 652 of file tls_schannel.c.

u8* tls_connection_server_handshake	(	void *	tls_ctx,
		struct tls_connection *	conn,
		const u8 *	in_data,
		size_t	in_len,
		size_t *	out_len
	)

Process TLS handshake (server side).

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	in_data	Input data from TLS peer
	in_len	Input data length
	out_len	Length of the output buffer.

Returns:

pointer to output data, NULL on failure

Caller is responsible for freeing returned output data.

Definition at line 474 of file tls_schannel.c.

int tls_connection_set_cipher_list	(	void *	tls_ctx,
		struct tls_connection *	conn,
		u8 *	ciphers
	)

Configure acceptable cipher suites.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	ciphers	Zero (TLS_CIPHER_NONE) terminated list of allowed ciphers (TLS_CIPHER_*).

Returns:

0 on success, -1 on failure

Definition at line 658 of file tls_schannel.c.

int tls_connection_set_ia	(	void *	tls_ctx,
		struct tls_connection *	conn,
		int	tls_ia
	)

Set TLS/IA parameters.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	tls_ia	1 = enable TLS/IA

Returns:

0 on success, -1 on failure

This function is used to configure TLS/IA in server mode where tls_connection_set_params() is not used.

Definition at line 762 of file tls_schannel.c.

int tls_connection_set_params	(	void *	tls_ctx,
		struct tls_connection *	conn,
		const struct tls_connection_params *	params
	)

Set TLS connection parameters.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	params	Connection parameters

Returns:

0 on success, -1 on failure, TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED (-2) on possible PIN error causing PKCS#11 engine failure, or TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED (-3) on failure to verify the PKCS#11 engine private key.

Definition at line 711 of file tls_schannel.c.

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int tls_connection_set_verify	(	void *	tls_ctx,
		struct tls_connection *	conn,
		int	verify_peer
	)

Set certificate verification options.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	verify_peer	1 = verify peer certificate

Returns:

0 on success, -1 on failure

Definition at line 180 of file tls_schannel.c.

int tls_connection_shutdown	(	void *	tls_ctx,
		struct tls_connection *	conn
	)

Shutdown TLS connection.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()

Returns:

0 on success, -1 on failure

Shutdown current TLS connection without releasing all resources. New connection can be started by using the same conn without having to call tls_connection_init() or setting certificates etc. again. The new connection should try to use session resumption.

Definition at line 151 of file tls_schannel.c.

void tls_deinit

(

void *

tls_ctx

)

Deinitialize TLS library.

Parameters:

tls_ctx

TLS context data from tls_init()

Called once during program shutdown and once for each RSN pre-authentication session. If global library deinitialization is needed (i.e., one that is shared between both authentication types), the TLS library wrapper should maintain a reference counter and do global deinitialization only when moving from 1 to 0 references.

Definition at line 106 of file tls_schannel.c.

int tls_get_cipher	(	void *	tls_ctx,
		struct tls_connection *	conn,
		char *	buf,
		size_t	buflen
	)

Get current cipher name.

Parameters:

	tls_ctx	TLS context data from tls_init()
	conn	Connection context data from tls_connection_init()
	buf	Buffer for the cipher name
	buflen	buf size

Returns:

0 on success, -1 on failure

Get the name of the currently used cipher.

Definition at line 665 of file tls_schannel.c.

int tls_get_errors

(

void *

tls_ctx

)

Process pending errors.

Parameters:

tls_ctx

TLS context data from tls_init()

Returns:

Number of found error, 0 if no errors detected.

Process all pending TLS errors.

Definition at line 117 of file tls_schannel.c.

int tls_global_set_params	(	void *	tls_ctx,
		const struct tls_connection_params *	params
	)

Set TLS parameters for all TLS connection.

Parameters:

	tls_ctx	TLS context data from tls_init()
	params	Global TLS parameters

Returns:

0 on success, -1 on failure, TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED (-2) on possible PIN error causing PKCS#11 engine failure, or TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED (-3) on failure to verify the PKCS#11 engine private key.

Definition at line 167 of file tls_schannel.c.

int tls_global_set_verify	(	void *	tls_ctx,
		int	check_crl
	)

Set global certificate verification options.

Parameters:

	tls_ctx	TLS context data from tls_init()
	check_crl	0 = do not verify CRLs, 1 = verify CRL for the user certificate, 2 = verify CRL for all certificates

Returns:

0 on success, -1 on failure

Definition at line 174 of file tls_schannel.c.

void* tls_init

(

const struct tls_config *

conf

)

Initialize TLS library.

Parameters:

conf

Configuration data for TLS library

Returns:

Context data to be used as tls_ctx in calls to other functions, or NULL on failure.

Called once during program startup and once for each RSN pre-authentication session. In other words, there can be two concurrent TLS contexts. If global library initialization is needed (i.e., one that is shared between both authentication types), the TLS library wrapper should maintain a reference counter and do global initialization only when moving from 0 to 1 reference.

Definition at line 91 of file tls_schannel.c.

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