[linux-block.git] / fs / cifs / asn1.c

/*
 * The ASB.1/BER parsing code is derived from ip_nat_snmp_basic.c which was in
 * turn derived from the gxsnmp package by Gregory McLean & Jochen Friedrich
 *
 * Copyright (c) 2000 RP Internet (www.rpi.net.au).
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifs_debug.h"
#include "cifsproto.h"

/*****************************************************************************
 *
 * Basic ASN.1 decoding routines (gxsnmp author Dirk Wisse)
 *
 *****************************************************************************/

/* Class */
#define ASN1_UNI	0	/* Universal */
#define ASN1_APL	1	/* Application */
#define ASN1_CTX	2	/* Context */
#define ASN1_PRV	3	/* Private */

/* Tag */
#define ASN1_EOC	0	/* End Of Contents or N/A */
#define ASN1_BOL	1	/* Boolean */
#define ASN1_INT	2	/* Integer */
#define ASN1_BTS	3	/* Bit String */
#define ASN1_OTS	4	/* Octet String */
#define ASN1_NUL	5	/* Null */
#define ASN1_OJI	6	/* Object Identifier  */
#define ASN1_OJD	7	/* Object Description */
#define ASN1_EXT	8	/* External */
#define ASN1_SEQ	16	/* Sequence */
#define ASN1_SET	17	/* Set */
#define ASN1_NUMSTR	18	/* Numerical String */
#define ASN1_PRNSTR	19	/* Printable String */
#define ASN1_TEXSTR	20	/* Teletext String */
#define ASN1_VIDSTR	21	/* Video String */
#define ASN1_IA5STR	22	/* IA5 String */
#define ASN1_UNITIM	23	/* Universal Time */
#define ASN1_GENTIM	24	/* General Time */
#define ASN1_GRASTR	25	/* Graphical String */
#define ASN1_VISSTR	26	/* Visible String */
#define ASN1_GENSTR	27	/* General String */

/* Primitive / Constructed methods*/
#define ASN1_PRI	0	/* Primitive */
#define ASN1_CON	1	/* Constructed */

/*
 * Error codes.
 */
#define ASN1_ERR_NOERROR		0
#define ASN1_ERR_DEC_EMPTY		2
#define ASN1_ERR_DEC_EOC_MISMATCH	3
#define ASN1_ERR_DEC_LENGTH_MISMATCH	4
#define ASN1_ERR_DEC_BADVALUE		5

#define SPNEGO_OID_LEN 7
#define NTLMSSP_OID_LEN  10
#define KRB5_OID_LEN  7
#define MSKRB5_OID_LEN  7
static unsigned long SPNEGO_OID[7] = { 1, 3, 6, 1, 5, 5, 2 };
static unsigned long NTLMSSP_OID[10] = { 1, 3, 6, 1, 4, 1, 311, 2, 2, 10 };
static unsigned long KRB5_OID[7] = { 1, 2, 840, 113554, 1, 2, 2 };
static unsigned long MSKRB5_OID[7] = { 1, 2, 840, 48018, 1, 2, 2 };

/*
 * ASN.1 context.
 */
struct asn1_ctx {
	int error;		/* Error condition */
	unsigned char *pointer;	/* Octet just to be decoded */
	unsigned char *begin;	/* First octet */
	unsigned char *end;	/* Octet after last octet */
};

/*
 * Octet string (not null terminated)
 */
struct asn1_octstr {
	unsigned char *data;
	unsigned int len;
};

static void
asn1_open(struct asn1_ctx *ctx, unsigned char *buf, unsigned int len)
{
	ctx->begin = buf;
	ctx->end = buf + len;
	ctx->pointer = buf;
	ctx->error = ASN1_ERR_NOERROR;
}

static unsigned char
asn1_octet_decode(struct asn1_ctx *ctx, unsigned char *ch)
{
	if (ctx->pointer >= ctx->end) {
		ctx->error = ASN1_ERR_DEC_EMPTY;
		return 0;
	}
	*ch = *(ctx->pointer)++;
	return 1;
}

static unsigned char
asn1_tag_decode(struct asn1_ctx *ctx, unsigned int *tag)
{
	unsigned char ch;

	*tag = 0;

	do {
		if (!asn1_octet_decode(ctx, &ch))
			return 0;
		*tag <<= 7;
		*tag |= ch & 0x7F;
	} while ((ch & 0x80) == 0x80);
	return 1;
}

static unsigned char
asn1_id_decode(struct asn1_ctx *ctx,
	       unsigned int *cls, unsigned int *con, unsigned int *tag)
{
	unsigned char ch;

	if (!asn1_octet_decode(ctx, &ch))
		return 0;

	*cls = (ch & 0xC0) >> 6;
	*con = (ch & 0x20) >> 5;
	*tag = (ch & 0x1F);

	if (*tag == 0x1F) {
		if (!asn1_tag_decode(ctx, tag))
			return 0;
	}
	return 1;
}

static unsigned char
asn1_length_decode(struct asn1_ctx *ctx, unsigned int *def, unsigned int *len)
{
	unsigned char ch, cnt;

	if (!asn1_octet_decode(ctx, &ch))
		return 0;

	if (ch == 0x80)
		*def = 0;
	else {
		*def = 1;

		if (ch < 0x80)
			*len = ch;
		else {
			cnt = (unsigned char) (ch & 0x7F);
			*len = 0;

			while (cnt > 0) {
				if (!asn1_octet_decode(ctx, &ch))
					return 0;
				*len <<= 8;
				*len |= ch;
				cnt--;
			}
		}
	}
	return 1;
}

static unsigned char
asn1_header_decode(struct asn1_ctx *ctx,
		   unsigned char **eoc,
		   unsigned int *cls, unsigned int *con, unsigned int *tag)
{
	unsigned int def = 0;
	unsigned int len = 0;

	if (!asn1_id_decode(ctx, cls, con, tag))
		return 0;

	if (!asn1_length_decode(ctx, &def, &len))
		return 0;

	if (def)
		*eoc = ctx->pointer + len;
	else
		*eoc = NULL;
	return 1;
}

static unsigned char
asn1_eoc_decode(struct asn1_ctx *ctx, unsigned char *eoc)
{
	unsigned char ch;

	if (eoc == NULL) {
		if (!asn1_octet_decode(ctx, &ch))
			return 0;

		if (ch != 0x00) {
			ctx->error = ASN1_ERR_DEC_EOC_MISMATCH;
			return 0;
		}

		if (!asn1_octet_decode(ctx, &ch))
			return 0;

		if (ch != 0x00) {
			ctx->error = ASN1_ERR_DEC_EOC_MISMATCH;
			return 0;
		}
		return 1;
	} else {
		if (ctx->pointer != eoc) {
			ctx->error = ASN1_ERR_DEC_LENGTH_MISMATCH;
			return 0;
		}
		return 1;
	}
}

/* static unsigned char asn1_null_decode(struct asn1_ctx *ctx,
				      unsigned char *eoc)
{
	ctx->pointer = eoc;
	return 1;
}

static unsigned char asn1_long_decode(struct asn1_ctx *ctx,
				      unsigned char *eoc, long *integer)
{
	unsigned char ch;
	unsigned int len;

	if (!asn1_octet_decode(ctx, &ch))
		return 0;

	*integer = (signed char) ch;
	len = 1;

	while (ctx->pointer < eoc) {
		if (++len > sizeof(long)) {
			ctx->error = ASN1_ERR_DEC_BADVALUE;
			return 0;
		}

		if (!asn1_octet_decode(ctx, &ch))
			return 0;

		*integer <<= 8;
		*integer |= ch;
	}
	return 1;
}

static unsigned char asn1_uint_decode(struct asn1_ctx *ctx,
				      unsigned char *eoc,
				      unsigned int *integer)
{
	unsigned char ch;
	unsigned int len;

	if (!asn1_octet_decode(ctx, &ch))
		return 0;

	*integer = ch;
	if (ch == 0)
		len = 0;
	else
		len = 1;

	while (ctx->pointer < eoc) {
		if (++len > sizeof(unsigned int)) {
			ctx->error = ASN1_ERR_DEC_BADVALUE;
			return 0;
		}

		if (!asn1_octet_decode(ctx, &ch))
			return 0;

		*integer <<= 8;
		*integer |= ch;
	}
	return 1;
}

static unsigned char asn1_ulong_decode(struct asn1_ctx *ctx,
				       unsigned char *eoc,
				       unsigned long *integer)
{
	unsigned char ch;
	unsigned int len;

	if (!asn1_octet_decode(ctx, &ch))
		return 0;

	*integer = ch;
	if (ch == 0)
		len = 0;
	else
		len = 1;

	while (ctx->pointer < eoc) {
		if (++len > sizeof(unsigned long)) {
			ctx->error = ASN1_ERR_DEC_BADVALUE;
			return 0;
		}

		if (!asn1_octet_decode(ctx, &ch))
			return 0;

		*integer <<= 8;
		*integer |= ch;
	}
	return 1;
}

static unsigned char
asn1_octets_decode(struct asn1_ctx *ctx,
		   unsigned char *eoc,
		   unsigned char **octets, unsigned int *len)
{
	unsigned char *ptr;

	*len = 0;

	*octets = kmalloc(eoc - ctx->pointer, GFP_ATOMIC);
	if (*octets == NULL) {
		return 0;
	}

	ptr = *octets;
	while (ctx->pointer < eoc) {
		if (!asn1_octet_decode(ctx, (unsigned char *) ptr++)) {
			kfree(*octets);
			*octets = NULL;
			return 0;
		}
		(*len)++;
	}
	return 1;
} */

static unsigned char
asn1_subid_decode(struct asn1_ctx *ctx, unsigned long *subid)
{
	unsigned char ch;

	*subid = 0;

	do {
		if (!asn1_octet_decode(ctx, &ch))
			return 0;

		*subid <<= 7;
		*subid |= ch & 0x7F;
	} while ((ch & 0x80) == 0x80);
	return 1;
}

static int
asn1_oid_decode(struct asn1_ctx *ctx,
		unsigned char *eoc, unsigned long **oid, unsigned int *len)
{
	unsigned long subid;
	unsigned int size;
	unsigned long *optr;

	size = eoc - ctx->pointer + 1;
	*oid = kmalloc(size * sizeof(unsigned long), GFP_ATOMIC);
	if (*oid == NULL)
		return 0;

	optr = *oid;

	if (!asn1_subid_decode(ctx, &subid)) {
		kfree(*oid);
		*oid = NULL;
		return 0;
	}

	if (subid < 40) {
		optr[0] = 0;
		optr[1] = subid;
	} else if (subid < 80) {
		optr[0] = 1;
		optr[1] = subid - 40;
	} else {
		optr[0] = 2;
		optr[1] = subid - 80;
	}

	*len = 2;
	optr += 2;

	while (ctx->pointer < eoc) {
		if (++(*len) > size) {
			ctx->error = ASN1_ERR_DEC_BADVALUE;
			kfree(*oid);
			*oid = NULL;
			return 0;
		}

		if (!asn1_subid_decode(ctx, optr++)) {
			kfree(*oid);
			*oid = NULL;
			return 0;
		}
	}
	return 1;
}

static int
compare_oid(unsigned long *oid1, unsigned int oid1len,
	    unsigned long *oid2, unsigned int oid2len)
{
	unsigned int i;

	if (oid1len != oid2len)
		return 0;
	else {
		for (i = 0; i < oid1len; i++) {
			if (oid1[i] != oid2[i])
				return 0;
		}
		return 1;
	}
}

	/* BB check for endian conversion issues here */

int
decode_negTokenInit(unsigned char *security_blob, int length,
		    enum securityEnum *secType)
{
	struct asn1_ctx ctx;
	unsigned char *end;
	unsigned char *sequence_end;
	unsigned long *oid = NULL;
	unsigned int cls, con, tag, oidlen, rc;
	int use_ntlmssp = FALSE;
	int use_kerberos = FALSE;

	*secType = NTLM; /* BB eventually make Kerberos or NLTMSSP the default*/

	/* cifs_dump_mem(" Received SecBlob ", security_blob, length); */

	asn1_open(&ctx, security_blob, length);

	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
		cFYI(1, ("Error decoding negTokenInit header"));
		return 0;
	} else if ((cls != ASN1_APL) || (con != ASN1_CON)
		   || (tag != ASN1_EOC)) {
		cFYI(1, ("cls = %d con = %d tag = %d", cls, con, tag));
		return 0;
	} else {
		/*      remember to free obj->oid */
		rc = asn1_header_decode(&ctx, &end, &cls, &con, &tag);
		if (rc) {
			if ((tag == ASN1_OJI) && (cls == ASN1_PRI)) {
				rc = asn1_oid_decode(&ctx, end, &oid, &oidlen);
				if (rc) {
					rc = compare_oid(oid, oidlen,
							 SPNEGO_OID,
							 SPNEGO_OID_LEN);
					kfree(oid);
				}
			} else
				rc = 0;
		}

		if (!rc) {
			cFYI(1, ("Error decoding negTokenInit header"));
			return 0;
		}

		if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
			cFYI(1, ("Error decoding negTokenInit"));
			return 0;
		} else if ((cls != ASN1_CTX) || (con != ASN1_CON)
			   || (tag != ASN1_EOC)) {
			cFYI(1,
			     ("cls = %d con = %d tag = %d end = %p (%d) exit 0",
			      cls, con, tag, end, *end));
			return 0;
		}

		if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
			cFYI(1, ("Error decoding negTokenInit"));
			return 0;
		} else if ((cls != ASN1_UNI) || (con != ASN1_CON)
			   || (tag != ASN1_SEQ)) {
			cFYI(1,
			     ("cls = %d con = %d tag = %d end = %p (%d) exit 1",
			      cls, con, tag, end, *end));
			return 0;
		}

		if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
			cFYI(1, ("Error decoding 2nd part of negTokenInit"));
			return 0;
		} else if ((cls != ASN1_CTX) || (con != ASN1_CON)
			   || (tag != ASN1_EOC)) {
			cFYI(1,
			     ("cls = %d con = %d tag = %d end = %p (%d) exit 0",
			      cls, con, tag, end, *end));
			return 0;
		}

		if (asn1_header_decode
		    (&ctx, &sequence_end, &cls, &con, &tag) == 0) {
			cFYI(1, ("Error decoding 2nd part of negTokenInit"));
			return 0;
		} else if ((cls != ASN1_UNI) || (con != ASN1_CON)
			   || (tag != ASN1_SEQ)) {
			cFYI(1,
			     ("cls = %d con = %d tag = %d end = %p (%d) exit 1",
			      cls, con, tag, end, *end));
			return 0;
		}

		while (!asn1_eoc_decode(&ctx, sequence_end)) {
			rc = asn1_header_decode(&ctx, &end, &cls, &con, &tag);
			if (!rc) {
				cFYI(1,
				     ("Error decoding negTokenInit hdr exit2"));
				return 0;
			}
			if ((tag == ASN1_OJI) && (con == ASN1_PRI)) {
				if (asn1_oid_decode(&ctx, end, &oid, &oidlen)) {

					cFYI(1,
					  ("OID len = %d oid = 0x%lx 0x%lx "
					   "0x%lx 0x%lx",
					   oidlen, *oid, *(oid + 1),
					   *(oid + 2), *(oid + 3)));

					if (compare_oid(oid, oidlen,
							MSKRB5_OID,
							MSKRB5_OID_LEN))
						use_kerberos = TRUE;
					else if (compare_oid(oid, oidlen,
							     KRB5_OID,
							     KRB5_OID_LEN))
						use_kerberos = TRUE;
					else if (compare_oid(oid, oidlen,
							     NTLMSSP_OID,
							     NTLMSSP_OID_LEN))
						use_ntlmssp = TRUE;

					kfree(oid);
				}
			} else {
				cFYI(1, ("Should be an oid what is going on?"));
			}
		}

		if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
			cFYI(1,
			     ("Error decoding last part negTokenInit exit3"));
			return 0;
		} else if ((cls != ASN1_CTX) || (con != ASN1_CON)) {
			/* tag = 3 indicating mechListMIC */
			cFYI(1,
			     ("Exit 4 cls = %d con = %d tag = %d end = %p (%d)",
			      cls, con, tag, end, *end));
			return 0;
		}
		if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
			cFYI(1,
			     ("Error decoding last part negTokenInit exit5"));
			return 0;
		} else if ((cls != ASN1_UNI) || (con != ASN1_CON)
			   || (tag != ASN1_SEQ)) {
			cFYI(1, ("cls = %d con = %d tag = %d end = %p (%d)",
				cls, con, tag, end, *end));
		}

		if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
			cFYI(1,
			     ("Error decoding last part negTokenInit exit 7"));
			return 0;
		} else if ((cls != ASN1_CTX) || (con != ASN1_CON)) {
			cFYI(1,
			     ("Exit 8 cls = %d con = %d tag = %d end = %p (%d)",
			      cls, con, tag, end, *end));
			return 0;
		}
		if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
			cFYI(1,
			     ("Error decoding last part negTokenInit exit9"));
			return 0;
		} else if ((cls != ASN1_UNI) || (con != ASN1_PRI)
			   || (tag != ASN1_GENSTR)) {
			cFYI(1,
			     ("Exit10 cls = %d con = %d tag = %d end = %p (%d)",
			      cls, con, tag, end, *end));
			return 0;
		}
		cFYI(1, ("Need to call asn1_octets_decode() function for %s",
			 ctx.pointer));	/* is this UTF-8 or ASCII? */
	}

	if (use_kerberos)
		*secType = Kerberos;
	else if (use_ntlmssp)
		*secType = NTLMSSP;

	return 1;
}
Commit	Line	Data
50c2f753	1	/*
1da177e4 LT	2	* The ASB.1/BER parsing code is derived from ip_nat_snmp_basic.c which was in
1da177e4 LT	3	* turn derived from the gxsnmp package by Gregory McLean & Jochen Friedrich
50c2f753	4	*
1da177e4 LT	5	* Copyright (c) 2000 RP Internet (www.rpi.net.au).
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	18	*/
	19
1da177e4 LT	20	#include <linux/module.h>
	21	#include <linux/types.h>
	22	#include <linux/kernel.h>
	23	#include <linux/mm.h>
	24	#include <linux/slab.h>
	25	#include "cifspdu.h"
	26	#include "cifsglob.h"
	27	#include "cifs_debug.h"
	28	#include "cifsproto.h"
	29
	30	/*****************************************************************************
	31	*
	32	* Basic ASN.1 decoding routines (gxsnmp author Dirk Wisse)
	33	*
	34	*****************************************************************************/
	35
	36	/* Class */
	37	#define ASN1_UNI 0 /* Universal */
	38	#define ASN1_APL 1 /* Application */
	39	#define ASN1_CTX 2 /* Context */
	40	#define ASN1_PRV 3 /* Private */
	41
	42	/* Tag */
	43	#define ASN1_EOC 0 /* End Of Contents or N/A */
	44	#define ASN1_BOL 1 /* Boolean */
	45	#define ASN1_INT 2 /* Integer */
	46	#define ASN1_BTS 3 /* Bit String */
	47	#define ASN1_OTS 4 /* Octet String */
	48	#define ASN1_NUL 5 /* Null */
	49	#define ASN1_OJI 6 /* Object Identifier */
	50	#define ASN1_OJD 7 /* Object Description */
	51	#define ASN1_EXT 8 /* External */
	52	#define ASN1_SEQ 16 /* Sequence */
	53	#define ASN1_SET 17 /* Set */
	54	#define ASN1_NUMSTR 18 /* Numerical String */
	55	#define ASN1_PRNSTR 19 /* Printable String */
	56	#define ASN1_TEXSTR 20 /* Teletext String */
	57	#define ASN1_VIDSTR 21 /* Video String */
	58	#define ASN1_IA5STR 22 /* IA5 String */
	59	#define ASN1_UNITIM 23 /* Universal Time */
	60	#define ASN1_GENTIM 24 /* General Time */
	61	#define ASN1_GRASTR 25 /* Graphical String */
	62	#define ASN1_VISSTR 26 /* Visible String */
	63	#define ASN1_GENSTR 27 /* General String */
	64
	65	/* Primitive / Constructed methods*/
	66	#define ASN1_PRI 0 /* Primitive */
	67	#define ASN1_CON 1 /* Constructed */
	68
	69	/*
	70	* Error codes.
	71	*/
	72	#define ASN1_ERR_NOERROR 0
	73	#define ASN1_ERR_DEC_EMPTY 2
	74	#define ASN1_ERR_DEC_EOC_MISMATCH 3
	75	#define ASN1_ERR_DEC_LENGTH_MISMATCH 4
	76	#define ASN1_ERR_DEC_BADVALUE 5
	77
	78	#define SPNEGO_OID_LEN 7
	79	#define NTLMSSP_OID_LEN 10
e545937a JL	80	#define KRB5_OID_LEN 7
e545937a JL	81	#define MSKRB5_OID_LEN 7
1da177e4 LT	82	static unsigned long SPNEGO_OID[7] = { 1, 3, 6, 1, 5, 5, 2 };
1da177e4 LT	83	static unsigned long NTLMSSP_OID[10] = { 1, 3, 6, 1, 4, 1, 311, 2, 2, 10 };
e545937a JL	84	static unsigned long KRB5_OID[7] = { 1, 2, 840, 113554, 1, 2, 2 };
e545937a JL	85	static unsigned long MSKRB5_OID[7] = { 1, 2, 840, 48018, 1, 2, 2 };
1da177e4	86
50c2f753	87	/*
1da177e4 LT	88	* ASN.1 context.
	89	*/
	90	struct asn1_ctx {
	91	int error; /* Error condition */
	92	unsigned char pointer; / Octet just to be decoded */
	93	unsigned char begin; / First octet */
	94	unsigned char end; / Octet after last octet */
	95	};
	96
	97	/*
	98	* Octet string (not null terminated)
	99	*/
	100	struct asn1_octstr {
	101	unsigned char *data;
	102	unsigned int len;
	103	};
	104
	105	static void
	106	asn1_open(struct asn1_ctx ctx, unsigned char buf, unsigned int len)
	107	{
	108	ctx->begin = buf;
	109	ctx->end = buf + len;
	110	ctx->pointer = buf;
	111	ctx->error = ASN1_ERR_NOERROR;
	112	}
	113
	114	static unsigned char
	115	asn1_octet_decode(struct asn1_ctx ctx, unsigned char ch)
	116	{
	117	if (ctx->pointer >= ctx->end) {
	118	ctx->error = ASN1_ERR_DEC_EMPTY;
	119	return 0;
	120	}
	121	ch = (ctx->pointer)++;
	122	return 1;
	123	}
	124
	125	static unsigned char
	126	asn1_tag_decode(struct asn1_ctx ctx, unsigned int tag)
	127	{
	128	unsigned char ch;
	129
	130	*tag = 0;
	131
	132	do {
	133	if (!asn1_octet_decode(ctx, &ch))
	134	return 0;
	135	*tag <<= 7;
	136	*tag \|= ch & 0x7F;
	137	} while ((ch & 0x80) == 0x80);
	138	return 1;
	139	}
	140
	141	static unsigned char
	142	asn1_id_decode(struct asn1_ctx *ctx,
	143	unsigned int cls, unsigned int con, unsigned int *tag)
	144	{
	145	unsigned char ch;
	146
	147	if (!asn1_octet_decode(ctx, &ch))
	148	return 0;
	149
	150	*cls = (ch & 0xC0) >> 6;
	151	*con = (ch & 0x20) >> 5;
152	*tag = (ch & 0x1F);
153
154	if (*tag == 0x1F) {
155	if (!asn1_tag_decode(ctx, tag))
156	return 0;
157	}
158	return 1;
159	}
160
161	static unsigned char
162	asn1_length_decode(struct asn1_ctx ctx, unsigned int def, unsigned int *len)
163	{
164	unsigned char ch, cnt;
165
166	if (!asn1_octet_decode(ctx, &ch))
167	return 0;
168
169	if (ch == 0x80)
170	*def = 0;
171	else {
172	*def = 1;
173
174	if (ch < 0x80)
175	*len = ch;
176	else {
177	cnt = (unsigned char) (ch & 0x7F);
178	*len = 0;
179
180	while (cnt > 0) {
181	if (!asn1_octet_decode(ctx, &ch))
182	return 0;
183	*len <<= 8;
184	*len \|= ch;
185	cnt--;
186	}
187	}
188	}
189	return 1;
190	}
191
192	static unsigned char
193	asn1_header_decode(struct asn1_ctx *ctx,
194	unsigned char **eoc,
195	unsigned int cls, unsigned int con, unsigned int *tag)
196	{
50c2f753	197	unsigned int def = 0;
ab2f218f	198	unsigned int len = 0;
1da177e4 LT	199
	200	if (!asn1_id_decode(ctx, cls, con, tag))
	201	return 0;
	202
	203	if (!asn1_length_decode(ctx, &def, &len))
	204	return 0;
	205
	206	if (def)
	207	*eoc = ctx->pointer + len;
	208	else
	209	*eoc = NULL;
	210	return 1;
	211	}
	212
	213	static unsigned char
	214	asn1_eoc_decode(struct asn1_ctx ctx, unsigned char eoc)
	215	{
	216	unsigned char ch;
	217
	218	if (eoc == NULL) {
	219	if (!asn1_octet_decode(ctx, &ch))
	220	return 0;
	221
	222	if (ch != 0x00) {
	223	ctx->error = ASN1_ERR_DEC_EOC_MISMATCH;
	224	return 0;
	225	}
	226
	227	if (!asn1_octet_decode(ctx, &ch))
	228	return 0;
	229
	230	if (ch != 0x00) {
	231	ctx->error = ASN1_ERR_DEC_EOC_MISMATCH;
	232	return 0;
	233	}
	234	return 1;
	235	} else {
	236	if (ctx->pointer != eoc) {
	237	ctx->error = ASN1_ERR_DEC_LENGTH_MISMATCH;
	238	return 0;
	239	}
	240	return 1;
	241	}
	242	}
	243
	244	/* static unsigned char asn1_null_decode(struct asn1_ctx *ctx,
	245	unsigned char *eoc)
	246	{
	247	ctx->pointer = eoc;
	248	return 1;
	249	}
	250
	251	static unsigned char asn1_long_decode(struct asn1_ctx *ctx,
	252	unsigned char eoc, long integer)
	253	{
	254	unsigned char ch;
	255	unsigned int len;
	256
	257	if (!asn1_octet_decode(ctx, &ch))
	258	return 0;
	259
	260	*integer = (signed char) ch;
	261	len = 1;
	262
263	while (ctx->pointer < eoc) {
264	if (++len > sizeof(long)) {
265	ctx->error = ASN1_ERR_DEC_BADVALUE;
266	return 0;
267	}
268
269	if (!asn1_octet_decode(ctx, &ch))
270	return 0;
271
272	*integer <<= 8;
273	*integer \|= ch;
274	}
275	return 1;
276	}
277
278	static unsigned char asn1_uint_decode(struct asn1_ctx *ctx,
279	unsigned char *eoc,
280	unsigned int *integer)
281	{
282	unsigned char ch;
283	unsigned int len;
284
285	if (!asn1_octet_decode(ctx, &ch))
286	return 0;
287
288	*integer = ch;
289	if (ch == 0)
290	len = 0;
291	else
292	len = 1;
293
294	while (ctx->pointer < eoc) {
295	if (++len > sizeof(unsigned int)) {
296	ctx->error = ASN1_ERR_DEC_BADVALUE;
297	return 0;
298	}
299
300	if (!asn1_octet_decode(ctx, &ch))
301	return 0;
302
303	*integer <<= 8;
304	*integer \|= ch;
305	}
306	return 1;
307	}
308
309	static unsigned char asn1_ulong_decode(struct asn1_ctx *ctx,
310	unsigned char *eoc,
311	unsigned long *integer)
312	{
313	unsigned char ch;
314	unsigned int len;
315
316	if (!asn1_octet_decode(ctx, &ch))
317	return 0;
318
319	*integer = ch;
320	if (ch == 0)
321	len = 0;
322	else
323	len = 1;
324
325	while (ctx->pointer < eoc) {
326	if (++len > sizeof(unsigned long)) {
327	ctx->error = ASN1_ERR_DEC_BADVALUE;
328	return 0;
329	}
330
331	if (!asn1_octet_decode(ctx, &ch))
332	return 0;
333
334	*integer <<= 8;
335	*integer \|= ch;
336	}
337	return 1;
50c2f753	338	}
1da177e4 LT	339
	340	static unsigned char
	341	asn1_octets_decode(struct asn1_ctx *ctx,
	342	unsigned char *eoc,
	343	unsigned char *octets, unsigned int len)
	344	{
	345	unsigned char *ptr;
	346
	347	*len = 0;
	348
	349	*octets = kmalloc(eoc - ctx->pointer, GFP_ATOMIC);
	350	if (*octets == NULL) {
	351	return 0;
	352	}
	353
	354	ptr = *octets;
	355	while (ctx->pointer < eoc) {
	356	if (!asn1_octet_decode(ctx, (unsigned char *) ptr++)) {
	357	kfree(*octets);
	358	*octets = NULL;
	359	return 0;
	360	}
	361	(*len)++;
	362	}
	363	return 1;
	364	} */
	365
	366	static unsigned char
	367	asn1_subid_decode(struct asn1_ctx ctx, unsigned long subid)
	368	{
	369	unsigned char ch;
	370
	371	*subid = 0;
	372
	373	do {
	374	if (!asn1_octet_decode(ctx, &ch))
	375	return 0;
	376
	377	*subid <<= 7;
	378	*subid \|= ch & 0x7F;
	379	} while ((ch & 0x80) == 0x80);
	380	return 1;
	381	}
	382
50c2f753	383	static int
1da177e4 LT	384	asn1_oid_decode(struct asn1_ctx *ctx,
	385	unsigned char eoc, unsigned long oid, unsigned int len)
	386	{
	387	unsigned long subid;
	388	unsigned int size;
	389	unsigned long *optr;
	390
	391	size = eoc - ctx->pointer + 1;
26f57364 SF	392	oid = kmalloc(size sizeof(unsigned long), GFP_ATOMIC);
26f57364 SF	393	if (*oid == NULL)
1da177e4	394	return 0;
1da177e4 LT	395
	396	optr = *oid;
	397
	398	if (!asn1_subid_decode(ctx, &subid)) {
	399	kfree(*oid);
	400	*oid = NULL;
	401	return 0;
	402	}
	403
	404	if (subid < 40) {
	405	optr[0] = 0;
	406	optr[1] = subid;
	407	} else if (subid < 80) {
	408	optr[0] = 1;
	409	optr[1] = subid - 40;
	410	} else {
	411	optr[0] = 2;
	412	optr[1] = subid - 80;
	413	}
	414
	415	*len = 2;
	416	optr += 2;
	417
	418	while (ctx->pointer < eoc) {
	419	if (++(*len) > size) {
	420	ctx->error = ASN1_ERR_DEC_BADVALUE;
	421	kfree(*oid);
	422	*oid = NULL;
	423	return 0;
	424	}
	425
	426	if (!asn1_subid_decode(ctx, optr++)) {
	427	kfree(*oid);
	428	*oid = NULL;
	429	return 0;
	430	}
	431	}
	432	return 1;
	433	}
	434
	435	static int
	436	compare_oid(unsigned long *oid1, unsigned int oid1len,
	437	unsigned long *oid2, unsigned int oid2len)
	438	{
	439	unsigned int i;
	440
	441	if (oid1len != oid2len)
	442	return 0;
	443	else {
	444	for (i = 0; i < oid1len; i++) {
	445	if (oid1[i] != oid2[i])
	446	return 0;
	447	}
	448	return 1;
	449	}
	450	}
	451
	452	/* BB check for endian conversion issues here */
	453
	454	int
	455	decode_negTokenInit(unsigned char *security_blob, int length,
	456	enum securityEnum *secType)
	457	{
	458	struct asn1_ctx ctx;
459	unsigned char *end;
460	unsigned char *sequence_end;
461	unsigned long *oid = NULL;
462	unsigned int cls, con, tag, oidlen, rc;
463	int use_ntlmssp = FALSE;
e545937a	464	int use_kerberos = FALSE;
1da177e4	465
50c2f753	466	secType = NTLM; / BB eventually make Kerberos or NLTMSSP the default*/
1da177e4 LT	467
	468	/* cifs_dump_mem(" Received SecBlob ", security_blob, length); */
	469
	470	asn1_open(&ctx, security_blob, length);
	471
	472	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
26a21b98	473	cFYI(1, ("Error decoding negTokenInit header"));
1da177e4 LT	474	return 0;
	475	} else if ((cls != ASN1_APL) \|\| (con != ASN1_CON)
	476	\|\| (tag != ASN1_EOC)) {
	477	cFYI(1, ("cls = %d con = %d tag = %d", cls, con, tag));
	478	return 0;
	479	} else {
	480	/* remember to free obj->oid */
	481	rc = asn1_header_decode(&ctx, &end, &cls, &con, &tag);
	482	if (rc) {
	483	if ((tag == ASN1_OJI) && (cls == ASN1_PRI)) {
	484	rc = asn1_oid_decode(&ctx, end, &oid, &oidlen);
	485	if (rc) {
	486	rc = compare_oid(oid, oidlen,
	487	SPNEGO_OID,
	488	SPNEGO_OID_LEN);
	489	kfree(oid);
	490	}
	491	} else
	492	rc = 0;
	493	}
	494
	495	if (!rc) {
	496	cFYI(1, ("Error decoding negTokenInit header"));
	497	return 0;
	498	}
	499
	500	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
26a21b98	501	cFYI(1, ("Error decoding negTokenInit"));
1da177e4 LT	502	return 0;
	503	} else if ((cls != ASN1_CTX) \|\| (con != ASN1_CON)
	504	\|\| (tag != ASN1_EOC)) {
50c2f753 SF	505	cFYI(1,
50c2f753 SF	506	("cls = %d con = %d tag = %d end = %p (%d) exit 0",
1da177e4 LT	507	cls, con, tag, end, *end));
	508	return 0;
	509	}
	510
	511	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
26a21b98	512	cFYI(1, ("Error decoding negTokenInit"));
1da177e4 LT	513	return 0;
	514	} else if ((cls != ASN1_UNI) \|\| (con != ASN1_CON)
	515	\|\| (tag != ASN1_SEQ)) {
50c2f753 SF	516	cFYI(1,
50c2f753 SF	517	("cls = %d con = %d tag = %d end = %p (%d) exit 1",
1da177e4 LT	518	cls, con, tag, end, *end));
	519	return 0;
	520	}
	521
	522	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
26a21b98	523	cFYI(1, ("Error decoding 2nd part of negTokenInit"));
1da177e4 LT	524	return 0;
	525	} else if ((cls != ASN1_CTX) \|\| (con != ASN1_CON)
	526	\|\| (tag != ASN1_EOC)) {
	527	cFYI(1,
	528	("cls = %d con = %d tag = %d end = %p (%d) exit 0",
	529	cls, con, tag, end, *end));
	530	return 0;
	531	}
	532
	533	if (asn1_header_decode
	534	(&ctx, &sequence_end, &cls, &con, &tag) == 0) {
26a21b98	535	cFYI(1, ("Error decoding 2nd part of negTokenInit"));
1da177e4 LT	536	return 0;
	537	} else if ((cls != ASN1_UNI) \|\| (con != ASN1_CON)
	538	\|\| (tag != ASN1_SEQ)) {
	539	cFYI(1,
	540	("cls = %d con = %d tag = %d end = %p (%d) exit 1",
	541	cls, con, tag, end, *end));
	542	return 0;
	543	}
	544
	545	while (!asn1_eoc_decode(&ctx, sequence_end)) {
	546	rc = asn1_header_decode(&ctx, &end, &cls, &con, &tag);
	547	if (!rc) {
	548	cFYI(1,
50c2f753	549	("Error decoding negTokenInit hdr exit2"));
1da177e4 LT	550	return 0;
	551	}
	552	if ((tag == ASN1_OJI) && (con == ASN1_PRI)) {
e545937a JL	553	if (asn1_oid_decode(&ctx, end, &oid, &oidlen)) {
e545937a JL	554
1da177e4	555	cFYI(1,
50c2f753 SF	556	("OID len = %d oid = 0x%lx 0x%lx "
	557	"0x%lx 0x%lx",
	558	oidlen, oid, (oid + 1),
	559	(oid + 2), (oid + 3)));
e545937a JL	560
	561	if (compare_oid(oid, oidlen,
	562	MSKRB5_OID,
	563	MSKRB5_OID_LEN))
	564	use_kerberos = TRUE;
	565	else if (compare_oid(oid, oidlen,
	566	KRB5_OID,
	567	KRB5_OID_LEN))
	568	use_kerberos = TRUE;
	569	else if (compare_oid(oid, oidlen,
	570	NTLMSSP_OID,
	571	NTLMSSP_OID_LEN))
1da177e4	572	use_ntlmssp = TRUE;
e545937a JL	573
e545937a JL	574	kfree(oid);
1da177e4 LT	575	}
1da177e4 LT	576	} else {
50c2f753	577	cFYI(1, ("Should be an oid what is going on?"));
1da177e4 LT	578	}
	579	}
	580
	581	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
	582	cFYI(1,
50c2f753	583	("Error decoding last part negTokenInit exit3"));
1da177e4	584	return 0;
50c2f753 SF	585	} else if ((cls != ASN1_CTX) \|\| (con != ASN1_CON)) {
50c2f753 SF	586	/* tag = 3 indicating mechListMIC */
1da177e4 LT	587	cFYI(1,
	588	("Exit 4 cls = %d con = %d tag = %d end = %p (%d)",
	589	cls, con, tag, end, *end));
	590	return 0;
	591	}
	592	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
	593	cFYI(1,
50c2f753	594	("Error decoding last part negTokenInit exit5"));
1da177e4 LT	595	return 0;
	596	} else if ((cls != ASN1_UNI) \|\| (con != ASN1_CON)
	597	\|\| (tag != ASN1_SEQ)) {
26f57364 SF	598	cFYI(1, ("cls = %d con = %d tag = %d end = %p (%d)",
26f57364 SF	599	cls, con, tag, end, *end));
1da177e4 LT	600	}
	601
	602	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
	603	cFYI(1,
50c2f753	604	("Error decoding last part negTokenInit exit 7"));
1da177e4 LT	605	return 0;
	606	} else if ((cls != ASN1_CTX) \|\| (con != ASN1_CON)) {
	607	cFYI(1,
	608	("Exit 8 cls = %d con = %d tag = %d end = %p (%d)",
	609	cls, con, tag, end, *end));
	610	return 0;
	611	}
	612	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
	613	cFYI(1,
50c2f753	614	("Error decoding last part negTokenInit exit9"));
1da177e4 LT	615	return 0;
	616	} else if ((cls != ASN1_UNI) \|\| (con != ASN1_PRI)
	617	\|\| (tag != ASN1_GENSTR)) {
	618	cFYI(1,
50c2f753	619	("Exit10 cls = %d con = %d tag = %d end = %p (%d)",
1da177e4 LT	620	cls, con, tag, end, *end));
	621	return 0;
	622	}
50c2f753 SF	623	cFYI(1, ("Need to call asn1_octets_decode() function for %s",
50c2f753 SF	624	ctx.pointer)); /* is this UTF-8 or ASCII? */
1da177e4 LT	625	}
1da177e4 LT	626
e545937a JL	627	if (use_kerberos)
	628	*secType = Kerberos;
	629	else if (use_ntlmssp)
1da177e4	630	*secType = NTLMSSP;
1da177e4 LT	631
	632	return 1;
	633	}