[net-next-2.6.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
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 };

/* 
 * 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;

	*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 1 decoding negTokenInit header exit 2"));
				return 0;
			}
			if ((tag == ASN1_OJI) && (con == ASN1_PRI)) {
				rc = asn1_oid_decode(&ctx, end, &oid, &oidlen);
				if(rc) {		
					cFYI(1,
					  ("OID len = %d oid = 0x%lx 0x%lx 0x%lx 0x%lx",
					   oidlen, *oid, *(oid + 1), *(oid + 2),
					   *(oid + 3)));
					rc = compare_oid(oid, oidlen, NTLMSSP_OID,
						 NTLMSSP_OID_LEN);
					kfree(oid);
					if (rc)
						use_ntlmssp = TRUE;
				}
			} else {
				cFYI(1,("This should be an oid what is going on? "));
			}
		}

		if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
			cFYI(1,
			     ("Error decoding last part of negTokenInit exit 3"));
			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 of negTokenInit exit 5"));
			return 0;
		} else if ((cls != ASN1_UNI) || (con != ASN1_CON)
			   || (tag != ASN1_SEQ)) {
			cFYI(1,
			     ("Exit 6 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 of 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 of negTokenInit exit 9"));
			return 0;
		} else if ((cls != ASN1_UNI) || (con != ASN1_PRI)
			   || (tag != ASN1_GENSTR)) {
			cFYI(1,
			     ("Exit 10 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 this %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
1da177e4 LT	1	/*
	2	* The ASB.1/BER parsing code is derived from ip_nat_snmp_basic.c which was in
	3	* turn derived from the gxsnmp package by Gregory McLean & Jochen Friedrich
	4	*
	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
	80	static unsigned long SPNEGO_OID[7] = { 1, 3, 6, 1, 5, 5, 2 };
	81	static unsigned long NTLMSSP_OID[10] = { 1, 3, 6, 1, 4, 1, 311, 2, 2, 10 };
	82
	83	/*
84	* ASN.1 context.
85	*/
86	struct asn1_ctx {
87	int error; /* Error condition */
88	unsigned char pointer; / Octet just to be decoded */
89	unsigned char begin; / First octet */
90	unsigned char end; / Octet after last octet */
91	};
92
93	/*
94	* Octet string (not null terminated)
95	*/
96	struct asn1_octstr {
97	unsigned char *data;
98	unsigned int len;
99	};
100
101	static void
102	asn1_open(struct asn1_ctx ctx, unsigned char buf, unsigned int len)
103	{
104	ctx->begin = buf;
105	ctx->end = buf + len;
106	ctx->pointer = buf;
107	ctx->error = ASN1_ERR_NOERROR;
108	}
109
110	static unsigned char
111	asn1_octet_decode(struct asn1_ctx ctx, unsigned char ch)
112	{
113	if (ctx->pointer >= ctx->end) {
114	ctx->error = ASN1_ERR_DEC_EMPTY;
115	return 0;
116	}
117	ch = (ctx->pointer)++;
118	return 1;
119	}
120
121	static unsigned char
122	asn1_tag_decode(struct asn1_ctx ctx, unsigned int tag)
123	{
124	unsigned char ch;
125
126	*tag = 0;
127
128	do {
129	if (!asn1_octet_decode(ctx, &ch))
130	return 0;
131	*tag <<= 7;
132	*tag \|= ch & 0x7F;
133	} while ((ch & 0x80) == 0x80);
134	return 1;
135	}
136
137	static unsigned char
138	asn1_id_decode(struct asn1_ctx *ctx,
139	unsigned int cls, unsigned int con, unsigned int *tag)
140	{
141	unsigned char ch;
142
143	if (!asn1_octet_decode(ctx, &ch))
144	return 0;
145
146	*cls = (ch & 0xC0) >> 6;
147	*con = (ch & 0x20) >> 5;
148	*tag = (ch & 0x1F);
149
150	if (*tag == 0x1F) {
151	if (!asn1_tag_decode(ctx, tag))
152	return 0;
153	}
154	return 1;
155	}
156
157	static unsigned char
158	asn1_length_decode(struct asn1_ctx ctx, unsigned int def, unsigned int *len)
159	{
160	unsigned char ch, cnt;
161
162	if (!asn1_octet_decode(ctx, &ch))
163	return 0;
164
165	if (ch == 0x80)
166	*def = 0;
167	else {
168	*def = 1;
169
170	if (ch < 0x80)
171	*len = ch;
172	else {
173	cnt = (unsigned char) (ch & 0x7F);
174	*len = 0;
175
176	while (cnt > 0) {
177	if (!asn1_octet_decode(ctx, &ch))
178	return 0;
179	*len <<= 8;
180	*len \|= ch;
181	cnt--;
182	}
183	}
184	}
185	return 1;
186	}
187
188	static unsigned char
189	asn1_header_decode(struct asn1_ctx *ctx,
190	unsigned char **eoc,
191	unsigned int cls, unsigned int con, unsigned int *tag)
192	{
ab2f218f SF	193	unsigned int def = 0;
ab2f218f SF	194	unsigned int len = 0;
1da177e4 LT	195
	196	if (!asn1_id_decode(ctx, cls, con, tag))
	197	return 0;
	198
	199	if (!asn1_length_decode(ctx, &def, &len))
	200	return 0;
	201
	202	if (def)
	203	*eoc = ctx->pointer + len;
	204	else
	205	*eoc = NULL;
	206	return 1;
	207	}
	208
	209	static unsigned char
	210	asn1_eoc_decode(struct asn1_ctx ctx, unsigned char eoc)
	211	{
	212	unsigned char ch;
	213
	214	if (eoc == NULL) {
	215	if (!asn1_octet_decode(ctx, &ch))
	216	return 0;
	217
	218	if (ch != 0x00) {
	219	ctx->error = ASN1_ERR_DEC_EOC_MISMATCH;
	220	return 0;
	221	}
	222
	223	if (!asn1_octet_decode(ctx, &ch))
	224	return 0;
	225
	226	if (ch != 0x00) {
	227	ctx->error = ASN1_ERR_DEC_EOC_MISMATCH;
	228	return 0;
	229	}
	230	return 1;
	231	} else {
	232	if (ctx->pointer != eoc) {
	233	ctx->error = ASN1_ERR_DEC_LENGTH_MISMATCH;
	234	return 0;
	235	}
	236	return 1;
	237	}
	238	}
	239
	240	/* static unsigned char asn1_null_decode(struct asn1_ctx *ctx,
	241	unsigned char *eoc)
	242	{
	243	ctx->pointer = eoc;
	244	return 1;
	245	}
	246
	247	static unsigned char asn1_long_decode(struct asn1_ctx *ctx,
	248	unsigned char eoc, long integer)
	249	{
	250	unsigned char ch;
	251	unsigned int len;
	252
	253	if (!asn1_octet_decode(ctx, &ch))
	254	return 0;
	255
	256	*integer = (signed char) ch;
	257	len = 1;
	258
259	while (ctx->pointer < eoc) {
260	if (++len > sizeof(long)) {
261	ctx->error = ASN1_ERR_DEC_BADVALUE;
262	return 0;
263	}
264
265	if (!asn1_octet_decode(ctx, &ch))
266	return 0;
267
268	*integer <<= 8;
269	*integer \|= ch;
270	}
271	return 1;
272	}
273
274	static unsigned char asn1_uint_decode(struct asn1_ctx *ctx,
275	unsigned char *eoc,
276	unsigned int *integer)
277	{
278	unsigned char ch;
279	unsigned int len;
280
281	if (!asn1_octet_decode(ctx, &ch))
282	return 0;
283
284	*integer = ch;
285	if (ch == 0)
286	len = 0;
287	else
288	len = 1;
289
290	while (ctx->pointer < eoc) {
291	if (++len > sizeof(unsigned int)) {
292	ctx->error = ASN1_ERR_DEC_BADVALUE;
293	return 0;
294	}
295
296	if (!asn1_octet_decode(ctx, &ch))
297	return 0;
298
299	*integer <<= 8;
300	*integer \|= ch;
301	}
302	return 1;
303	}
304
305	static unsigned char asn1_ulong_decode(struct asn1_ctx *ctx,
306	unsigned char *eoc,
307	unsigned long *integer)
308	{
309	unsigned char ch;
310	unsigned int len;
311
312	if (!asn1_octet_decode(ctx, &ch))
313	return 0;
314
315	*integer = ch;
316	if (ch == 0)
317	len = 0;
318	else
319	len = 1;
320
321	while (ctx->pointer < eoc) {
322	if (++len > sizeof(unsigned long)) {
323	ctx->error = ASN1_ERR_DEC_BADVALUE;
324	return 0;
325	}
326
327	if (!asn1_octet_decode(ctx, &ch))
328	return 0;
329
330	*integer <<= 8;
331	*integer \|= ch;
332	}
333	return 1;
334	}
335
336	static unsigned char
337	asn1_octets_decode(struct asn1_ctx *ctx,
338	unsigned char *eoc,
339	unsigned char *octets, unsigned int len)
340	{
341	unsigned char *ptr;
342
343	*len = 0;
344
345	*octets = kmalloc(eoc - ctx->pointer, GFP_ATOMIC);
346	if (*octets == NULL) {
347	return 0;
348	}
349
350	ptr = *octets;
351	while (ctx->pointer < eoc) {
352	if (!asn1_octet_decode(ctx, (unsigned char *) ptr++)) {
353	kfree(*octets);
354	*octets = NULL;
355	return 0;
356	}
357	(*len)++;
358	}
359	return 1;
360	} */
361
362	static unsigned char
363	asn1_subid_decode(struct asn1_ctx ctx, unsigned long subid)
364	{
365	unsigned char ch;
366
367	*subid = 0;
368
369	do {
370	if (!asn1_octet_decode(ctx, &ch))
371	return 0;
372
373	*subid <<= 7;
374	*subid \|= ch & 0x7F;
375	} while ((ch & 0x80) == 0x80);
376	return 1;
377	}
378
379	static int
380	asn1_oid_decode(struct asn1_ctx *ctx,
381	unsigned char eoc, unsigned long oid, unsigned int len)
382	{
383	unsigned long subid;
384	unsigned int size;
385	unsigned long *optr;
386
387	size = eoc - ctx->pointer + 1;
388	oid = kmalloc(size sizeof (unsigned long), GFP_ATOMIC);
389	if (*oid == NULL) {
390	return 0;
391	}
392
393	optr = *oid;
394
395	if (!asn1_subid_decode(ctx, &subid)) {
396	kfree(*oid);
397	*oid = NULL;
398	return 0;
399	}
400
401	if (subid < 40) {
402	optr[0] = 0;
403	optr[1] = subid;
404	} else if (subid < 80) {
405	optr[0] = 1;
406	optr[1] = subid - 40;
407	} else {
408	optr[0] = 2;
409	optr[1] = subid - 80;
410	}
411
412	*len = 2;
413	optr += 2;
414
415	while (ctx->pointer < eoc) {
416	if (++(*len) > size) {
417	ctx->error = ASN1_ERR_DEC_BADVALUE;
418	kfree(*oid);
419	*oid = NULL;
420	return 0;
421	}
422
423	if (!asn1_subid_decode(ctx, optr++)) {
424	kfree(*oid);
425	*oid = NULL;
426	return 0;
427	}
428	}
429	return 1;
430	}
431
432	static int
433	compare_oid(unsigned long *oid1, unsigned int oid1len,
434	unsigned long *oid2, unsigned int oid2len)
435	{
436	unsigned int i;
437
438	if (oid1len != oid2len)
439	return 0;
440	else {
441	for (i = 0; i < oid1len; i++) {
442	if (oid1[i] != oid2[i])
443	return 0;
444	}
445	return 1;
446	}
447	}
448
449	/* BB check for endian conversion issues here */
450
451	int
452	decode_negTokenInit(unsigned char *security_blob, int length,
453	enum securityEnum *secType)
454	{
455	struct asn1_ctx ctx;
456	unsigned char *end;
457	unsigned char *sequence_end;
458	unsigned long *oid = NULL;
459	unsigned int cls, con, tag, oidlen, rc;
460	int use_ntlmssp = FALSE;
461
462	secType = NTLM; / BB eventually make Kerberos or NLTMSSP the default */
463
464	/* cifs_dump_mem(" Received SecBlob ", security_blob, length); */
465
466	asn1_open(&ctx, security_blob, length);
467
468	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
26a21b98	469	cFYI(1, ("Error decoding negTokenInit header"));
1da177e4 LT	470	return 0;
	471	} else if ((cls != ASN1_APL) \|\| (con != ASN1_CON)
	472	\|\| (tag != ASN1_EOC)) {
	473	cFYI(1, ("cls = %d con = %d tag = %d", cls, con, tag));
	474	return 0;
	475	} else {
	476	/* remember to free obj->oid */
	477	rc = asn1_header_decode(&ctx, &end, &cls, &con, &tag);
	478	if (rc) {
	479	if ((tag == ASN1_OJI) && (cls == ASN1_PRI)) {
	480	rc = asn1_oid_decode(&ctx, end, &oid, &oidlen);
	481	if (rc) {
	482	rc = compare_oid(oid, oidlen,
	483	SPNEGO_OID,
	484	SPNEGO_OID_LEN);
	485	kfree(oid);
	486	}
	487	} else
	488	rc = 0;
	489	}
	490
	491	if (!rc) {
	492	cFYI(1, ("Error decoding negTokenInit header"));
	493	return 0;
	494	}
	495
	496	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
26a21b98	497	cFYI(1, ("Error decoding negTokenInit"));
1da177e4 LT	498	return 0;
	499	} else if ((cls != ASN1_CTX) \|\| (con != ASN1_CON)
	500	\|\| (tag != ASN1_EOC)) {
	501	cFYI(1,("cls = %d con = %d tag = %d end = %p (%d) exit 0",
	502	cls, con, tag, end, *end));
	503	return 0;
	504	}
	505
	506	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
26a21b98	507	cFYI(1, ("Error decoding negTokenInit"));
1da177e4 LT	508	return 0;
	509	} else if ((cls != ASN1_UNI) \|\| (con != ASN1_CON)
	510	\|\| (tag != ASN1_SEQ)) {
	511	cFYI(1,("cls = %d con = %d tag = %d end = %p (%d) exit 1",
	512	cls, con, tag, end, *end));
	513	return 0;
	514	}
	515
	516	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
26a21b98	517	cFYI(1, ("Error decoding 2nd part of negTokenInit"));
1da177e4 LT	518	return 0;
	519	} else if ((cls != ASN1_CTX) \|\| (con != ASN1_CON)
	520	\|\| (tag != ASN1_EOC)) {
	521	cFYI(1,
	522	("cls = %d con = %d tag = %d end = %p (%d) exit 0",
	523	cls, con, tag, end, *end));
	524	return 0;
	525	}
	526
	527	if (asn1_header_decode
	528	(&ctx, &sequence_end, &cls, &con, &tag) == 0) {
26a21b98	529	cFYI(1, ("Error decoding 2nd part of negTokenInit"));
1da177e4 LT	530	return 0;
	531	} else if ((cls != ASN1_UNI) \|\| (con != ASN1_CON)
	532	\|\| (tag != ASN1_SEQ)) {
	533	cFYI(1,
	534	("cls = %d con = %d tag = %d end = %p (%d) exit 1",
	535	cls, con, tag, end, *end));
	536	return 0;
	537	}
	538
	539	while (!asn1_eoc_decode(&ctx, sequence_end)) {
	540	rc = asn1_header_decode(&ctx, &end, &cls, &con, &tag);
	541	if (!rc) {
	542	cFYI(1,
	543	("Error 1 decoding negTokenInit header exit 2"));
	544	return 0;
	545	}
	546	if ((tag == ASN1_OJI) && (con == ASN1_PRI)) {
	547	rc = asn1_oid_decode(&ctx, end, &oid, &oidlen);
	548	if(rc) {
	549	cFYI(1,
	550	("OID len = %d oid = 0x%lx 0x%lx 0x%lx 0x%lx",
	551	oidlen, oid, (oid + 1), *(oid + 2),
	552	*(oid + 3)));
	553	rc = compare_oid(oid, oidlen, NTLMSSP_OID,
	554	NTLMSSP_OID_LEN);
f99d49ad	555	kfree(oid);
1da177e4 LT	556	if (rc)
	557	use_ntlmssp = TRUE;
	558	}
	559	} else {
	560	cFYI(1,("This should be an oid what is going on? "));
	561	}
	562	}
	563
	564	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
	565	cFYI(1,
	566	("Error decoding last part of negTokenInit exit 3"));
	567	return 0;
	568	} else if ((cls != ASN1_CTX) \|\| (con != ASN1_CON)) { /* tag = 3 indicating mechListMIC */
	569	cFYI(1,
	570	("Exit 4 cls = %d con = %d tag = %d end = %p (%d)",
	571	cls, con, tag, end, *end));
	572	return 0;
	573	}
	574	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
	575	cFYI(1,
	576	("Error decoding last part of negTokenInit exit 5"));
	577	return 0;
	578	} else if ((cls != ASN1_UNI) \|\| (con != ASN1_CON)
	579	\|\| (tag != ASN1_SEQ)) {
	580	cFYI(1,
	581	("Exit 6 cls = %d con = %d tag = %d end = %p (%d)",
	582	cls, con, tag, end, *end));
	583	}
	584
	585	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
	586	cFYI(1,
	587	("Error decoding last part of negTokenInit exit 7"));
	588	return 0;
	589	} else if ((cls != ASN1_CTX) \|\| (con != ASN1_CON)) {
	590	cFYI(1,
	591	("Exit 8 cls = %d con = %d tag = %d end = %p (%d)",
	592	cls, con, tag, end, *end));
	593	return 0;
	594	}
	595	if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
	596	cFYI(1,
	597	("Error decoding last part of negTokenInit exit 9"));
	598	return 0;
	599	} else if ((cls != ASN1_UNI) \|\| (con != ASN1_PRI)
	600	\|\| (tag != ASN1_GENSTR)) {
	601	cFYI(1,
	602	("Exit 10 cls = %d con = %d tag = %d end = %p (%d)",
	603	cls, con, tag, end, *end));
	604	return 0;
	605	}
	606	cFYI(1, ("Need to call asn1_octets_decode() function for this %s", ctx.pointer)); /* is this UTF-8 or ASCII? */
	607	}
	608
	609	/* if (use_kerberos)
	610	*secType = Kerberos
	611	else */
	612	if (use_ntlmssp) {
	613	*secType = NTLMSSP;
	614	}
	615
	616	return 1;
	617	}