@@ -19,6 +19,7 @@ config CIFS
select CRYPTO_LIB_DES
select KEYS
select DNS_RESOLVER
+ select ASN1
help
This is the client VFS module for the SMB3 family of NAS protocols,
(including support for the most recent, most secure dialect SMB3.1.1)
@@ -5,13 +5,15 @@
ccflags-y += -I$(src) # needed for trace events
obj-$(CONFIG_CIFS) += cifs.o
+$(obj)/spnego_negtokeninit.asn1.o: $(obj)/spnego_negtokeninit.asn1.c $(obj)/spnego_negtokeninit.asn1.h
+
cifs-y := trace.o cifsfs.o cifssmb.o cifs_debug.o connect.o dir.o file.o \
inode.o link.o misc.o netmisc.o smbencrypt.o transport.o asn1.o \
cifs_unicode.o nterr.o cifsencrypt.o \
readdir.o ioctl.o sess.o export.o smb1ops.o unc.o winucase.o \
smb2ops.o smb2maperror.o smb2transport.o \
smb2misc.o smb2pdu.o smb2inode.o smb2file.o cifsacl.o fs_context.o \
- dns_resolve.o
+ dns_resolve.o spnego_negtokeninit.asn1.o
cifs-$(CONFIG_CIFS_XATTR) += xattr.o
@@ -1,612 +1,62 @@
// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * 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).
- */
#include <linux/module.h>
-#include <linux/types.h>
#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include "cifspdu.h"
+#include <linux/oid_registry.h>
#include "cifsglob.h"
#include "cifs_debug.h"
-#include "cifsproto.h"
+#include "spnego_negtokeninit.asn1.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_ENUM 10 /* Enumerated */
-#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 KRB5U2U_OID_LEN 8
-#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 KRB5U2U_OID[8] = { 1, 2, 840, 113554, 1, 2, 2, 3 };
-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;
-}
-
-#if 0 /* will be needed later by spnego decoding/encoding of ntlmssp */
-static unsigned char
-asn1_enum_decode(struct asn1_ctx *ctx, __le32 *val)
-{
- unsigned char ch;
-
- if (ctx->pointer >= ctx->end) {
- ctx->error = ASN1_ERR_DEC_EMPTY;
- return 0;
- }
-
- ch = *(ctx->pointer)++; /* ch has 0xa, ptr points to length octet */
- if ((ch) == ASN1_ENUM) /* if ch value is ENUM, 0xa */
- *val = *(++(ctx->pointer)); /* value has enum value */
- else
- return 0;
-
- ctx->pointer++;
- return 1;
-}
-#endif
-
-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--;
- }
- }
- }
-
- /* don't trust len bigger than ctx buffer */
- if (*len > ctx->end - ctx->pointer)
- return 0;
-
- 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;
-
- /* primitive shall be definite, indefinite shall be constructed */
- if (*con == ASN1_PRI && !def)
- 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)
+int
+decode_negTokenInit(unsigned char *security_blob, int length,
+ struct TCP_Server_Info *server)
{
- 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;
- }
+ if (asn1_ber_decoder(&spnego_negtokeninit_decoder, server,
+ security_blob, length) == 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)
+int gssapi_this_mech(void *context, size_t hdrlen,
+ unsigned char tag, const void *value, size_t vlen)
{
- 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;
-
- /* first subid actually encodes first two subids */
- if (size < 2 || size > UINT_MAX/sizeof(unsigned long))
- return 0;
-
- *oid = kmalloc_array(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;
+ enum OID oid;
- while (ctx->pointer < eoc) {
- if (++(*len) > size) {
- ctx->error = ASN1_ERR_DEC_BADVALUE;
- kfree(*oid);
- *oid = NULL;
- return 0;
- }
+ oid = look_up_OID(value, vlen);
+ if (oid != OID_spnego) {
+ char buf[50];
- if (!asn1_subid_decode(ctx, optr++)) {
- kfree(*oid);
- *oid = NULL;
- return 0;
- }
+ sprint_oid(value, vlen, buf, sizeof(buf));
+ cifs_dbg(FYI, "Error decoding negTokenInit header: unexpected OID %s\n",
+ buf);
+ return -EBADMSG;
}
- return 1;
+ return 0;
}
-static int
-compare_oid(unsigned long *oid1, unsigned int oid1len,
- unsigned long *oid2, unsigned int oid2len)
+int neg_token_init_mech_type(void *context, size_t hdrlen,
+ unsigned char tag,
+ const void *value, size_t vlen)
{
- unsigned int i;
+ struct TCP_Server_Info *server = context;
+ enum OID oid;
- if (oid1len != oid2len)
- return 0;
+ oid = look_up_OID(value, vlen);
+ if (oid == OID_mskrb5)
+ server->sec_mskerberos = true;
+ else if (oid == OID_krb5u2u)
+ server->sec_kerberosu2u = true;
+ else if (oid == OID_krb5)
+ server->sec_kerberos = true;
+ else if (oid == OID_ntlmssp)
+ server->sec_ntlmssp = true;
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,
- struct TCP_Server_Info *server)
-{
- struct asn1_ctx ctx;
- unsigned char *end;
- unsigned char *sequence_end;
- unsigned long *oid = NULL;
- unsigned int cls, con, tag, oidlen, rc;
-
- /* cifs_dump_mem(" Received SecBlob ", security_blob, length); */
-
- asn1_open(&ctx, security_blob, length);
+ char buf[50];
- /* GSSAPI header */
- if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
- cifs_dbg(FYI, "Error decoding negTokenInit header\n");
- return 0;
- } else if ((cls != ASN1_APL) || (con != ASN1_CON)
- || (tag != ASN1_EOC)) {
- cifs_dbg(FYI, "cls = %d con = %d tag = %d\n", cls, con, tag);
- return 0;
+ sprint_oid(value, vlen, buf, sizeof(buf));
+ cifs_dbg(FYI, "Decoding negTokenInit: unsupported OID %s\n",
+ buf);
}
-
- /* Check for SPNEGO OID -- remember to free obj->oid */
- rc = asn1_header_decode(&ctx, &end, &cls, &con, &tag);
- if (rc) {
- if ((tag == ASN1_OJI) && (con == ASN1_PRI) &&
- (cls == ASN1_UNI)) {
- 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;
- }
-
- /* SPNEGO OID not present or garbled -- bail out */
- if (!rc) {
- cifs_dbg(FYI, "Error decoding negTokenInit header\n");
- return 0;
- }
-
- /* SPNEGO */
- if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
- cifs_dbg(FYI, "Error decoding negTokenInit\n");
- return 0;
- } else if ((cls != ASN1_CTX) || (con != ASN1_CON)
- || (tag != ASN1_EOC)) {
- cifs_dbg(FYI, "cls = %d con = %d tag = %d end = %p exit 0\n",
- cls, con, tag, end);
- return 0;
- }
-
- /* negTokenInit */
- if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
- cifs_dbg(FYI, "Error decoding negTokenInit\n");
- return 0;
- } else if ((cls != ASN1_UNI) || (con != ASN1_CON)
- || (tag != ASN1_SEQ)) {
- cifs_dbg(FYI, "cls = %d con = %d tag = %d end = %p exit 1\n",
- cls, con, tag, end);
- return 0;
- }
-
- /* sequence */
- if (asn1_header_decode(&ctx, &end, &cls, &con, &tag) == 0) {
- cifs_dbg(FYI, "Error decoding 2nd part of negTokenInit\n");
- return 0;
- } else if ((cls != ASN1_CTX) || (con != ASN1_CON)
- || (tag != ASN1_EOC)) {
- cifs_dbg(FYI, "cls = %d con = %d tag = %d end = %p exit 0\n",
- cls, con, tag, end);
- return 0;
- }
-
- /* sequence of */
- if (asn1_header_decode
- (&ctx, &sequence_end, &cls, &con, &tag) == 0) {
- cifs_dbg(FYI, "Error decoding 2nd part of negTokenInit\n");
- return 0;
- } else if ((cls != ASN1_UNI) || (con != ASN1_CON)
- || (tag != ASN1_SEQ)) {
- cifs_dbg(FYI, "cls = %d con = %d tag = %d sequence_end = %p exit 1\n",
- cls, con, tag, sequence_end);
- return 0;
- }
-
- /* list of security mechanisms */
- while (!asn1_eoc_decode(&ctx, sequence_end)) {
- rc = asn1_header_decode(&ctx, &end, &cls, &con, &tag);
- if (!rc) {
- cifs_dbg(FYI, "Error decoding negTokenInit hdr exit2\n");
- return 0;
- }
- if ((tag == ASN1_OJI) && (con == ASN1_PRI)) {
- if (asn1_oid_decode(&ctx, end, &oid, &oidlen)) {
-
- cifs_dbg(FYI, "OID len = %d oid = 0x%lx 0x%lx 0x%lx 0x%lx\n",
- oidlen, *oid, *(oid + 1), *(oid + 2),
- *(oid + 3));
-
- if (compare_oid(oid, oidlen, MSKRB5_OID,
- MSKRB5_OID_LEN))
- server->sec_mskerberos = true;
- else if (compare_oid(oid, oidlen, KRB5U2U_OID,
- KRB5U2U_OID_LEN))
- server->sec_kerberosu2u = true;
- else if (compare_oid(oid, oidlen, KRB5_OID,
- KRB5_OID_LEN))
- server->sec_kerberos = true;
- else if (compare_oid(oid, oidlen, NTLMSSP_OID,
- NTLMSSP_OID_LEN))
- server->sec_ntlmssp = true;
-
- kfree(oid);
- }
- } else {
- cifs_dbg(FYI, "Should be an oid what is going on?\n");
- }
- }
-
- /*
- * We currently ignore anything at the end of the SPNEGO blob after
- * the mechTypes have been parsed, since none of that info is
- * used at the moment.
- */
- return 1;
+ return 0;
}
new file mode 100644
@@ -0,0 +1,40 @@
+GSSAPI ::=
+ [APPLICATION 0] IMPLICIT SEQUENCE {
+ thisMech
+ OBJECT IDENTIFIER ({gssapi_this_mech}),
+ negotiationToken
+ NegotiationToken
+ }
+
+MechType ::= OBJECT IDENTIFIER ({neg_token_init_mech_type})
+
+MechTypeList ::= SEQUENCE OF MechType
+
+NegHints ::= SEQUENCE {
+ hintName
+ [0] GeneralString OPTIONAL,
+ hintAddress
+ [1] OCTET STRING OPTIONAL
+ }
+
+NegTokenInit2 ::=
+ SEQUENCE {
+ mechTypes
+ [0] MechTypeList OPTIONAL,
+ reqFlags
+ [1] BIT STRING OPTIONAL,
+ mechToken
+ [2] OCTET STRING OPTIONAL,
+ negHints
+ [3] NegHints OPTIONAL,
+ mechListMIC
+ [3] OCTET STRING OPTIONAL
+ }
+
+NegotiationToken ::=
+ CHOICE {
+ negTokenInit
+ [0] NegTokenInit2,
+ negTokenTarg
+ [1] ANY
+ }
@@ -54,6 +54,10 @@ enum OID {
OID_md4, /* 1.2.840.113549.2.4 */
OID_md5, /* 1.2.840.113549.2.5 */
+ OID_mskrb5, /* 1.2.840.48018.1.2.2 */
+ OID_krb5, /* 1.2.840.113554.1.2.2 */
+ OID_krb5u2u, /* 1.2.840.113554.1.2.2.3 */
+
/* Microsoft Authenticode & Software Publishing */
OID_msIndirectData, /* 1.3.6.1.4.1.311.2.1.4 */
OID_msStatementType, /* 1.3.6.1.4.1.311.2.1.11 */
@@ -62,6 +66,10 @@ enum OID {
OID_msIndividualSPKeyPurpose, /* 1.3.6.1.4.1.311.2.1.21 */
OID_msOutlookExpress, /* 1.3.6.1.4.1.311.16.4 */
+ OID_ntlmssp, /* 1.3.6.1.4.1.311.2.2.10 */
+
+ OID_spnego, /* 1.3.6.1.5.5.2 */
+
OID_certAuthInfoAccess, /* 1.3.6.1.5.5.7.1.1 */
OID_sha1, /* 1.3.14.3.2.26 */
OID_id_ansip384r1, /* 1.3.132.0.34 */
Decode negTokenInit with lib/asn1_decoder. For that, add OIDs in linux/oid_registry.h and a negTokenInit ASN1 file, "spnego_negtokeninit.asn1". And define decoder's callback functions, which are the gssapi_this_mech for checking SPENGO oid and the neg_token_init_mech_type for getting authentication mechanisms supported by a server. Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com> --- fs/cifs/Kconfig | 1 + fs/cifs/Makefile | 4 +- fs/cifs/asn1.c | 624 ++----------------------------- fs/cifs/spnego_negtokeninit.asn1 | 40 ++ include/linux/oid_registry.h | 8 + 5 files changed, 89 insertions(+), 588 deletions(-) create mode 100644 fs/cifs/spnego_negtokeninit.asn1