/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License, Version 1.0 only

 * (the "License").  You may not use this file except in compliance

 * with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.

 * Use is subject to license terms.

 */

/*

 * A module that implements a dummy security mechanism.

 * It's mainly used to test GSS-API application. Multiple tokens

 * exchanged during security context establishment can be

 * specified through dummy_mech.conf located in /etc.

 */

#include <sys/types.h>

#include <sys/modctl.h>

#include <sys/errno.h>

#include <gssapiP_dummy.h>

#include <gssapi_err_generic.h>

#include <mechglueP.h>

#include <gssapi/kgssapi_defs.h>

#include <sys/debug.h>

#ifdef DUMMY_MECH_DEBUG

/*

 * Kernel kgssd module debugging aid. The global variable "dummy_mech_log"

 * is a bit mask which allows various types of debugging messages

 * to be printed out.

 *

 *       dummy_mech_log & 1  will cause actual failures to be printed.

 *       dummy_mech_log & 2  will cause informational messages to be

 *                       printed on the client side of kgssd.

 *       dummy_mech_log & 4  will cause informational messages to be

 *                       printed on the server side of kgssd.

 *       dummy_mech_log & 8  will cause informational messages to be

 *                       printed on both client and server side of kgssd.

 */

uint_t dummy_mech_log = 1;

#endif

/* Local defines */

#define	MAGIC_TOKEN_NUMBER 12345

/* private routines for dummy_mechanism */

static gss_buffer_desc make_dummy_token_msg(void *data, int datalen);

static int der_length_size(int);

static void der_write_length(unsigned char **, int);

static int der_read_length(unsigned char **, int *);

static int g_token_size(gss_OID mech, unsigned int body_size);

static void g_make_token_header(gss_OID mech, int body_size,

				unsigned char **buf, int tok_type);

static int g_verify_token_header(gss_OID mech, int *body_size,

				unsigned char **buf_in, int tok_type,

				int toksize);

/* private global variables */

static int dummy_token_nums;

/*

 * This OID:

 * { iso(1) org(3) internet(6) dod(1) private(4) enterprises(1) sun(42)

 * products(2) gssapi(26) mechtypes(1) dummy(2) }

 */

static struct gss_config dummy_mechanism =

	{{10, "\053\006\001\004\001\052\002\032\001\002"},

	NULL,	/* context */

	NULL,	/* next */

	TRUE,	/* uses_kmod */

/* EXPORT DELETE START */ /* CRYPT DELETE START */

	dummy_gss_unseal,

/* EXPORT DELETE END */ /* CRYPT DELETE END */

	dummy_gss_delete_sec_context,

/* EXPORT DELETE START */ /* CRYPT DELETE START */

	dummy_gss_seal,

/* EXPORT DELETE END */ /* CRYPT DELETE END */

	dummy_gss_import_sec_context,

/* EXPORT DELETE START */

/* CRYPT DELETE START */

#if 0

/* CRYPT DELETE END */

	dummy_gss_seal,

	dummy_gss_unseal,

/* CRYPT DELETE START */

#endif

/* CRYPT DELETE END */

/* EXPORT DELETE END */

	dummy_gss_sign,

	dummy_gss_verify

};

static gss_mechanism

gss_mech_initialize()

{

	dprintf("Entering gss_mech_initialize\n");

	if (dummy_token_nums == 0)

		dummy_token_nums = 1;

	dprintf("Leaving gss_mech_initialize\n");

	return (&dummy_mechanism);

}

/*

 * Clean up after a failed mod_install()

 */

static void

gss_mech_fini()

{

	/* Nothing to do */

}

/*

 * Module linkage information for the kernel.

 */

extern struct mod_ops mod_miscops;

static struct modlmisc modlmisc = {

	&mod_miscops, "in-kernel dummy GSS mechanism"

};

static struct modlinkage modlinkage = {

	MODREV_1,

	(void *)&modlmisc,

	NULL

};

static int dummy_fini_code = EBUSY;

int

_init()

{

	int retval;

	gss_mechanism mech, tmp;

	mech = gss_mech_initialize();

	mutex_enter(&__kgss_mech_lock);

	tmp = __kgss_get_mechanism(&mech->mech_type);

	if (tmp != NULL) {

		DUMMY_MECH_LOG0(8,

			"dummy GSS mechanism: mechanism already in table.\n");

		if (tmp->uses_kmod == TRUE) {

			DUMMY_MECH_LOG0(8, "dummy GSS mechanism: mechanism "

				"table supports kernel operations!\n");

		}

		/*

		 * keep us loaded, but let us be unloadable. This

		 * will give the developer time to trouble shoot

		 */

		dummy_fini_code = 0;

	} else {

		__kgss_add_mechanism(mech);

		ASSERT(__kgss_get_mechanism(&mech->mech_type) == mech);

	}

	mutex_exit(&__kgss_mech_lock);

	if ((retval = mod_install(&modlinkage)) != 0)

		gss_mech_fini();	/* clean up */

	return (retval);

}

int

_fini()

{

	int ret = dummy_fini_code;

	if (ret == 0) {

		ret = (mod_remove(&modlinkage));

	}

	return (ret);

}

int

_info(struct modinfo *modinfop)

{

	return (mod_info(&modlinkage, modinfop));

}

/*ARGSUSED*/

static OM_uint32

dummy_gss_sign(context, minor_status, context_handle,

		qop_req, message_buffer, message_token,

		gssd_ctx_verifier)

	void *context;

	OM_uint32 *minor_status;

	gss_ctx_id_t context_handle;

	int qop_req;

	gss_buffer_t message_buffer;

	gss_buffer_t message_token;

	OM_uint32 gssd_ctx_verifier;

{

	dummy_gss_ctx_id_rec	*ctx;

	char token_string[] = "dummy_gss_sign";

	dprintf("Entering gss_sign\n");

	if (context_handle == GSS_C_NO_CONTEXT)

		return (GSS_S_NO_CONTEXT);

	ctx = (dummy_gss_ctx_id_rec *) context_handle;

	ASSERT(ctx->established == 1);

	ASSERT(ctx->token_number == MAGIC_TOKEN_NUMBER);

	*message_token = make_dummy_token_msg(

				token_string, strlen(token_string));

	dprintf("Leaving gss_sign\n");

	return (GSS_S_COMPLETE);

}

/*ARGSUSED*/

static OM_uint32

	dummy_gss_verify(context, minor_status, context_handle,

		message_buffer, token_buffer, qop_state,

		gssd_ctx_verifier)

	void *context;

	OM_uint32 *minor_status;

	gss_ctx_id_t context_handle;

	gss_buffer_t message_buffer;

	gss_buffer_t token_buffer;

	int *qop_state;

	OM_uint32 gssd_ctx_verifier;

{

	unsigned char *ptr;

	int bodysize;

	int err;

	dummy_gss_ctx_id_rec	*ctx;

	dprintf("Entering gss_verify\n");

	if (context_handle == GSS_C_NO_CONTEXT)

		return (GSS_S_NO_CONTEXT);

	ctx = (dummy_gss_ctx_id_rec *) context_handle;

	ASSERT(ctx->established == 1);

	ASSERT(ctx->token_number == MAGIC_TOKEN_NUMBER);

	/* Check for defective input token. */

	ptr = (unsigned char *) token_buffer->value;

	if (err = g_verify_token_header((gss_OID)gss_mech_dummy, &bodysize,

					&ptr, 0,

					token_buffer->length)) {

		*minor_status = err;

		return (GSS_S_DEFECTIVE_TOKEN);

	}

	*qop_state = GSS_C_QOP_DEFAULT;

	dprintf("Leaving gss_verify\n");

	return (GSS_S_COMPLETE);

}

/* EXPORT DELETE START */

/*ARGSUSED*/

static OM_uint32

dummy_gss_seal(context, minor_status, context_handle, conf_req_flag,

		qop_req, input_message_buffer, conf_state,

		output_message_buffer, gssd_ctx_verifier)

	void *context;

	OM_uint32 *minor_status;

	gss_ctx_id_t context_handle;

	int conf_req_flag;

	int qop_req;

	gss_buffer_t input_message_buffer;

	int *conf_state;

	gss_buffer_t output_message_buffer;

	OM_uint32 gssd_ctx_verifier;

{

	gss_buffer_desc	output;

	dummy_gss_ctx_id_rec	*ctx;

	dprintf("Entering gss_seal\n");

	if (context_handle == GSS_C_NO_CONTEXT)

		return (GSS_S_NO_CONTEXT);

	ctx = (dummy_gss_ctx_id_rec *) context_handle;

	ASSERT(ctx->established == 1);

	ASSERT(ctx->token_number == MAGIC_TOKEN_NUMBER);

	/* Copy the input message to output message */

	output = make_dummy_token_msg(

		input_message_buffer->value, input_message_buffer->length);

	if (conf_state)

		*conf_state = 1;

	*output_message_buffer = output;

	dprintf("Leaving gss_seal\n");

	return (GSS_S_COMPLETE);

}

/*ARGSUSED*/

static OM_uint32

dummy_gss_unseal(context, minor_status, context_handle,

		input_message_buffer, output_message_buffer,

		conf_state, qop_state, gssd_ctx_verifier)

	void *context;

	OM_uint32 *minor_status;

	gss_ctx_id_t context_handle;

	gss_buffer_t input_message_buffer;

	gss_buffer_t output_message_buffer;

	int *conf_state;

	int *qop_state;

	OM_uint32 gssd_ctx_verifier;

{

	gss_buffer_desc output;

	dummy_gss_ctx_id_rec	*ctx;

	unsigned char *ptr;

	int bodysize;

	int err;

	dprintf("Entering gss_unseal\n");

	if (context_handle == GSS_C_NO_CONTEXT)

		return (GSS_S_NO_CONTEXT);

	ctx = (dummy_gss_ctx_id_rec *) context_handle;

	ASSERT(ctx->established == 1);

	ASSERT(ctx->token_number == MAGIC_TOKEN_NUMBER);

	ptr = (unsigned char *) input_message_buffer->value;

	if (err = g_verify_token_header((gss_OID)gss_mech_dummy, &bodysize,

					&ptr, 0,

					input_message_buffer->length)) {

		*minor_status = err;

		return (GSS_S_DEFECTIVE_TOKEN);

	}

	output.length = bodysize;

	output.value = (void *)MALLOC(output.length);

	(void) memcpy(output.value, ptr, output.length);

	*output_message_buffer = output;

	*qop_state = GSS_C_QOP_DEFAULT;

	if (conf_state)

		*conf_state = 1;

	dprintf("Leaving gss_unseal\n");

	return (GSS_S_COMPLETE);

}

/* EXPORT DELETE END */

/*ARGSUSED*/

OM_uint32

	dummy_gss_import_sec_context(ct, minor_status, interprocess_token,

					context_handle)

void *ct;

OM_uint32 *minor_status;

gss_buffer_t interprocess_token;

gss_ctx_id_t *context_handle;

{

	unsigned char *ptr;

	int bodysize;

	int err;

	/* Assume that we got ctx from the interprocess token. */

	dummy_gss_ctx_id_t ctx;

	dprintf("Entering import_sec_context\n");

	ptr = (unsigned char *) interprocess_token->value;

	if (err = g_verify_token_header((gss_OID)gss_mech_dummy, &bodysize,

					&ptr, 0,

					interprocess_token->length)) {

		*minor_status = err;

		return (GSS_S_DEFECTIVE_TOKEN);

	}

	ctx = (dummy_gss_ctx_id_t)MALLOC(sizeof (dummy_gss_ctx_id_rec));

	ctx->token_number = MAGIC_TOKEN_NUMBER;

	ctx->established = 1;

	*context_handle = (gss_ctx_id_t)ctx;

	dprintf("Leaving import_sec_context\n");

	return (GSS_S_COMPLETE);

}

/*ARGSUSED*/

static OM_uint32

dummy_gss_delete_sec_context(ct, minor_status,

			context_handle, output_token,

			gssd_ctx_verifier)

void *ct;

OM_uint32 *minor_status;

gss_ctx_id_t *context_handle;

gss_buffer_t output_token;

OM_uint32 gssd_ctx_verifier;

{

	dummy_gss_ctx_id_t ctx;

	dprintf("Entering delete_sec_context\n");

	/* Make the length to 0, so the output token is not sent to peer */

	if (output_token) {

		output_token->length = 0;

		output_token->value = NULL;

	}

	if (*context_handle == GSS_C_NO_CONTEXT) {

		*minor_status = 0;

		return (GSS_S_COMPLETE);

	}

	ctx = (dummy_gss_ctx_id_rec *) *context_handle;

	ASSERT(ctx->established == 1);

	ASSERT(ctx->token_number == MAGIC_TOKEN_NUMBER);

	FREE(ctx, sizeof (dummy_gss_ctx_id_rec));

	*context_handle = GSS_C_NO_CONTEXT;

	dprintf("Leaving delete_sec_context\n");

	return (GSS_S_COMPLETE);

}

static int

der_length_size(int length)

{

	if (length < (1<<7))

		return (1);

	else if (length < (1<<8))

		return (2);

	else if (length < (1<<16))

		return (3);

	else if (length < (1<<24))

		return (4);

	else

		return (5);

}

static void

der_write_length(unsigned char ** buf, int length)

{

	if (length < (1<<7)) {

		*(*buf)++ = (unsigned char) length;

	} else {

		*(*buf)++ = (unsigned char) (der_length_size(length)+127);

		if (length >= (1<<24))

			*(*buf)++ = (unsigned char) (length>>24);

		if (length >= (1<<16))

			*(*buf)++ = (unsigned char) ((length>>16)&0xff);

		if (length >= (1<<8))

			*(*buf)++ = (unsigned char) ((length>>8)&0xff);

		*(*buf)++ = (unsigned char) (length&0xff);

	}

}

static int

der_read_length(buf, bufsize)

unsigned char **buf;

int *bufsize;

{

	unsigned char sf;

	int ret;

	if (*bufsize < 1)

		return (-1);

	sf = *(*buf)++;

	(*bufsize)--;

	if (sf & 0x80) {

		if ((sf &= 0x7f) > ((*bufsize)-1))

			return (-1);

		if (sf > DUMMY_SIZE_OF_INT)

			return (-1);

		ret = 0;

		for (; sf; sf--) {

			ret = (ret<<8) + (*(*buf)++);

			(*bufsize)--;

		}

	} else {

		ret = sf;

	}

	return (ret);

}

static int

g_token_size(mech, body_size)

	gss_OID mech;

	unsigned int body_size;

{

	/* set body_size to sequence contents size */

	body_size += 4 + (int)mech->length;	/* NEED overflow check */

	return (1 + der_length_size(body_size) + body_size);

}

static void

g_make_token_header(mech, body_size, buf, tok_type)

	gss_OID mech;

	int body_size;

	unsigned char **buf;

	int tok_type;

{

	*(*buf)++ = 0x60;

	der_write_length(buf, 4 + mech->length + body_size);

	*(*buf)++ = 0x06;

	*(*buf)++ = (unsigned char) mech->length;

	TWRITE_STR(*buf, mech->elements, ((int)mech->length));

	*(*buf)++ = (unsigned char) ((tok_type>>8)&0xff);

	*(*buf)++ = (unsigned char) (tok_type&0xff);

}

static int

g_verify_token_header(mech, body_size, buf_in, tok_type, toksize)

	gss_OID mech;