* [PATCH v4] cifs: decoding negTokenInit with generic ASN1 decoder
@ 2021-06-06 1:06 Hyunchul Lee
2021-06-06 7:11 ` Steve French
0 siblings, 1 reply; 3+ messages in thread
From: Hyunchul Lee @ 2021-06-06 1:06 UTC (permalink / raw)
To: Steve French, David Howells
Cc: kernel-team, Namjae Jeon, linux-kernel, linux-cifs,
samba-technical, Hyunchul Lee
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>
---
changes from v3:
- Change Makefile to fix a compile error, "spnego_negtokeninit.asn1.h: No such file or directory".
changes from v2:
- Change Makefile to fix a compile error(kernel test bot).
- Add cifsproto.h into asn1.c to fix a compile warning(kernel test bot).
chnages from v1:
- Select CONFIG_OID_REGISTRY
fs/cifs/Kconfig | 2 +
fs/cifs/Makefile | 8 +-
fs/cifs/asn1.c | 623 ++-----------------------------
fs/cifs/spnego_negtokeninit.asn1 | 40 ++
include/linux/oid_registry.h | 8 +
5 files changed, 93 insertions(+), 588 deletions(-)
create mode 100644 fs/cifs/spnego_negtokeninit.asn1
diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index bf52e9326ebe..7de5c893c181 100644
--- a/fs/cifs/Kconfig
+++ b/fs/cifs/Kconfig
@@ -19,6 +19,8 @@ config CIFS
select CRYPTO_LIB_DES
select KEYS
select DNS_RESOLVER
+ select ASN1
+ select OID_REGISTRY
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)
diff --git a/fs/cifs/Makefile b/fs/cifs/Makefile
index 3ee3b7de4ded..9d877eafd350 100644
--- a/fs/cifs/Makefile
+++ b/fs/cifs/Makefile
@@ -6,12 +6,16 @@ ccflags-y += -I$(src) # needed for trace events
obj-$(CONFIG_CIFS) += cifs.o
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 \
+ inode.o link.o misc.o netmisc.o smbencrypt.o transport.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 asn1.o
+
+$(obj)/asn1.o: $(obj)/spnego_negtokeninit.asn1.h
+
+$(obj)/spnego_negtokeninit.asn1.o: $(obj)/spnego_negtokeninit.asn1.c $(obj)/spnego_negtokeninit.asn1.h
cifs-$(CONFIG_CIFS_XATTR) += xattr.o
diff --git a/fs/cifs/asn1.c b/fs/cifs/asn1.c
index 3150c19cdc2f..2db95fe3abfb 100644
--- a/fs/cifs/asn1.c
+++ b/fs/cifs/asn1.c
@@ -1,612 +1,63 @@
// 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;
}
diff --git a/fs/cifs/spnego_negtokeninit.asn1 b/fs/cifs/spnego_negtokeninit.asn1
new file mode 100644
index 000000000000..aa5b4a61b3f5
--- /dev/null
+++ b/fs/cifs/spnego_negtokeninit.asn1
@@ -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
+ }
diff --git a/include/linux/oid_registry.h b/include/linux/oid_registry.h
index 461b7aa587ba..3d8db1f6a5db 100644
--- a/include/linux/oid_registry.h
+++ b/include/linux/oid_registry.h
@@ -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 */
--
2.25.1
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH v4] cifs: decoding negTokenInit with generic ASN1 decoder
2021-06-06 1:06 [PATCH v4] cifs: decoding negTokenInit with generic ASN1 decoder Hyunchul Lee
@ 2021-06-06 7:11 ` Steve French
2021-06-06 7:52 ` Hyunchul Lee
0 siblings, 1 reply; 3+ messages in thread
From: Steve French @ 2021-06-06 7:11 UTC (permalink / raw)
To: Hyunchul Lee
Cc: Steve French, David Howells, kernel-team, Namjae Jeon, LKML,
CIFS, samba-technical
"make M=fs/cifs" from the top of the kernel tree worked, but my usual
script failed
"cd fs/cifs"
then
"make C=1 -C /usr/src/linux-headers-`uname -r` M=`pwd` modules
CF=-D__CHECK_ENDIAN__"
failed with (even after generating the files with the "make M=fs/cifs" earlier):
ASN.1 /home/smfrench/cifs-2.6/fs/cifs/spnego_negtokeninit.asn1.[ch]
CC [M] /home/smfrench/cifs-2.6/fs/cifs/asn1.o
/home/smfrench/cifs-2.6/fs/cifs/asn1.c: In function ‘gssapi_this_mech’:
/home/smfrench/cifs-2.6/fs/cifs/asn1.c:28:13: error: ‘OID_spnego’
undeclared (first use in this function)
28 | if (oid != OID_spnego) {
| ^~~~~~~~~~
/home/smfrench/cifs-2.6/fs/cifs/asn1.c:28:13: note: each undeclared
identifier is reported only once for each function it appears in
/home/smfrench/cifs-2.6/fs/cifs/asn1.c: In function ‘neg_token_init_mech_type’:
/home/smfrench/cifs-2.6/fs/cifs/asn1.c:47:13: error: ‘OID_mskrb5’
undeclared (first use in this function); did you mean ‘OID_md5’?
47 | if (oid == OID_mskrb5)
| ^~~~~~~~~~
| OID_md5
/home/smfrench/cifs-2.6/fs/cifs/asn1.c:49:18: error: ‘OID_krb5u2u’
undeclared (first use in this function)
49 | else if (oid == OID_krb5u2u)
| ^~~~~~~~~~~
/home/smfrench/cifs-2.6/fs/cifs/asn1.c:51:18: error: ‘OID_krb5’
undeclared (first use in this function)
51 | else if (oid == OID_krb5)
| ^~~~~~~~
/home/smfrench/cifs-2.6/fs/cifs/asn1.c:53:18: error: ‘OID_ntlmssp’
undeclared (first use in this function)
53 | else if (oid == OID_ntlmssp)
| ^~~~~~~~~~~
make[1]: *** [scripts/Makefile.build:272:
/home/smfrench/cifs-2.6/fs/cifs/asn1.o] Error 1
make: *** [Makefile:1845: /home/smfrench/cifs-2.6/fs/cifs] Error 2
make: Leaving directory
'/usr/src/linux-headers-5.13.0-051300rc3daily20210526-generic
On Sat, Jun 5, 2021 at 8:07 PM Hyunchul Lee <hyc.lee@gmail.com> wrote:
>
> 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>
> ---
> changes from v3:
> - Change Makefile to fix a compile error, "spnego_negtokeninit.asn1.h: No such file or directory".
> changes from v2:
> - Change Makefile to fix a compile error(kernel test bot).
> - Add cifsproto.h into asn1.c to fix a compile warning(kernel test bot).
> chnages from v1:
> - Select CONFIG_OID_REGISTRY
>
> fs/cifs/Kconfig | 2 +
> fs/cifs/Makefile | 8 +-
> fs/cifs/asn1.c | 623 ++-----------------------------
> fs/cifs/spnego_negtokeninit.asn1 | 40 ++
> include/linux/oid_registry.h | 8 +
> 5 files changed, 93 insertions(+), 588 deletions(-)
> create mode 100644 fs/cifs/spnego_negtokeninit.asn1
>
> diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
> index bf52e9326ebe..7de5c893c181 100644
> --- a/fs/cifs/Kconfig
> +++ b/fs/cifs/Kconfig
> @@ -19,6 +19,8 @@ config CIFS
> select CRYPTO_LIB_DES
> select KEYS
> select DNS_RESOLVER
> + select ASN1
> + select OID_REGISTRY
> 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)
> diff --git a/fs/cifs/Makefile b/fs/cifs/Makefile
> index 3ee3b7de4ded..9d877eafd350 100644
> --- a/fs/cifs/Makefile
> +++ b/fs/cifs/Makefile
> @@ -6,12 +6,16 @@ ccflags-y += -I$(src) # needed for trace events
> obj-$(CONFIG_CIFS) += cifs.o
>
> 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 \
> + inode.o link.o misc.o netmisc.o smbencrypt.o transport.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 asn1.o
> +
> +$(obj)/asn1.o: $(obj)/spnego_negtokeninit.asn1.h
> +
> +$(obj)/spnego_negtokeninit.asn1.o: $(obj)/spnego_negtokeninit.asn1.c $(obj)/spnego_negtokeninit.asn1.h
>
> cifs-$(CONFIG_CIFS_XATTR) += xattr.o
>
> diff --git a/fs/cifs/asn1.c b/fs/cifs/asn1.c
> index 3150c19cdc2f..2db95fe3abfb 100644
> --- a/fs/cifs/asn1.c
> +++ b/fs/cifs/asn1.c
> @@ -1,612 +1,63 @@
> // 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;
> }
> diff --git a/fs/cifs/spnego_negtokeninit.asn1 b/fs/cifs/spnego_negtokeninit.asn1
> new file mode 100644
> index 000000000000..aa5b4a61b3f5
> --- /dev/null
> +++ b/fs/cifs/spnego_negtokeninit.asn1
> @@ -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
> + }
> diff --git a/include/linux/oid_registry.h b/include/linux/oid_registry.h
> index 461b7aa587ba..3d8db1f6a5db 100644
> --- a/include/linux/oid_registry.h
> +++ b/include/linux/oid_registry.h
> @@ -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 */
> --
> 2.25.1
>
--
Thanks,
Steve
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH v4] cifs: decoding negTokenInit with generic ASN1 decoder
2021-06-06 7:11 ` Steve French
@ 2021-06-06 7:52 ` Hyunchul Lee
0 siblings, 0 replies; 3+ messages in thread
From: Hyunchul Lee @ 2021-06-06 7:52 UTC (permalink / raw)
To: Steve French
Cc: Steve French, David Howells, kernel-team, Namjae Jeon, LKML,
CIFS, samba-technical
2021년 6월 6일 (일) 오후 4:11, Steve French <smfrench@gmail.com>님이 작성:
>
> "make M=fs/cifs" from the top of the kernel tree worked, but my usual
> script failed
>
> "cd fs/cifs"
> then
> "make C=1 -C /usr/src/linux-headers-`uname -r` M=`pwd` modules
> CF=-D__CHECK_ENDIAN__"
>
> failed with (even after generating the files with the "make M=fs/cifs" earlier):
>
> ASN.1 /home/smfrench/cifs-2.6/fs/cifs/spnego_negtokeninit.asn1.[ch]
> CC [M] /home/smfrench/cifs-2.6/fs/cifs/asn1.o
> /home/smfrench/cifs-2.6/fs/cifs/asn1.c: In function ‘gssapi_this_mech’:
> /home/smfrench/cifs-2.6/fs/cifs/asn1.c:28:13: error: ‘OID_spnego’
> undeclared (first use in this function)
> 28 | if (oid != OID_spnego) {
> | ^~~~~~~~~~
Because this patch have added some enum constants such as OID_spnego into
include/linux/oid_registry.h, compiling cifs with new linux headers is needed.
Thanks,
Hyunchul
> /home/smfrench/cifs-2.6/fs/cifs/asn1.c:28:13: note: each undeclared
> identifier is reported only once for each function it appears in
> /home/smfrench/cifs-2.6/fs/cifs/asn1.c: In function ‘neg_token_init_mech_type’:
> /home/smfrench/cifs-2.6/fs/cifs/asn1.c:47:13: error: ‘OID_mskrb5’
> undeclared (first use in this function); did you mean ‘OID_md5’?
> 47 | if (oid == OID_mskrb5)
> | ^~~~~~~~~~
> | OID_md5
> /home/smfrench/cifs-2.6/fs/cifs/asn1.c:49:18: error: ‘OID_krb5u2u’
> undeclared (first use in this function)
> 49 | else if (oid == OID_krb5u2u)
> | ^~~~~~~~~~~
> /home/smfrench/cifs-2.6/fs/cifs/asn1.c:51:18: error: ‘OID_krb5’
> undeclared (first use in this function)
> 51 | else if (oid == OID_krb5)
> | ^~~~~~~~
> /home/smfrench/cifs-2.6/fs/cifs/asn1.c:53:18: error: ‘OID_ntlmssp’
> undeclared (first use in this function)
> 53 | else if (oid == OID_ntlmssp)
> | ^~~~~~~~~~~
> make[1]: *** [scripts/Makefile.build:272:
> /home/smfrench/cifs-2.6/fs/cifs/asn1.o] Error 1
> make: *** [Makefile:1845: /home/smfrench/cifs-2.6/fs/cifs] Error 2
> make: Leaving directory
> '/usr/src/linux-headers-5.13.0-051300rc3daily20210526-generic
>
> On Sat, Jun 5, 2021 at 8:07 PM Hyunchul Lee <hyc.lee@gmail.com> wrote:
> >
> > 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>
> > ---
> > changes from v3:
> > - Change Makefile to fix a compile error, "spnego_negtokeninit.asn1.h: No such file or directory".
> > changes from v2:
> > - Change Makefile to fix a compile error(kernel test bot).
> > - Add cifsproto.h into asn1.c to fix a compile warning(kernel test bot).
> > chnages from v1:
> > - Select CONFIG_OID_REGISTRY
> >
> > fs/cifs/Kconfig | 2 +
> > fs/cifs/Makefile | 8 +-
> > fs/cifs/asn1.c | 623 ++-----------------------------
> > fs/cifs/spnego_negtokeninit.asn1 | 40 ++
> > include/linux/oid_registry.h | 8 +
> > 5 files changed, 93 insertions(+), 588 deletions(-)
> > create mode 100644 fs/cifs/spnego_negtokeninit.asn1
> >
> > diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
> > index bf52e9326ebe..7de5c893c181 100644
> > --- a/fs/cifs/Kconfig
> > +++ b/fs/cifs/Kconfig
> > @@ -19,6 +19,8 @@ config CIFS
> > select CRYPTO_LIB_DES
> > select KEYS
> > select DNS_RESOLVER
> > + select ASN1
> > + select OID_REGISTRY
> > 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)
> > diff --git a/fs/cifs/Makefile b/fs/cifs/Makefile
> > index 3ee3b7de4ded..9d877eafd350 100644
> > --- a/fs/cifs/Makefile
> > +++ b/fs/cifs/Makefile
> > @@ -6,12 +6,16 @@ ccflags-y += -I$(src) # needed for trace events
> > obj-$(CONFIG_CIFS) += cifs.o
> >
> > 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 \
> > + inode.o link.o misc.o netmisc.o smbencrypt.o transport.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 asn1.o
> > +
> > +$(obj)/asn1.o: $(obj)/spnego_negtokeninit.asn1.h
> > +
> > +$(obj)/spnego_negtokeninit.asn1.o: $(obj)/spnego_negtokeninit.asn1.c $(obj)/spnego_negtokeninit.asn1.h
> >
> > cifs-$(CONFIG_CIFS_XATTR) += xattr.o
> >
> > diff --git a/fs/cifs/asn1.c b/fs/cifs/asn1.c
> > index 3150c19cdc2f..2db95fe3abfb 100644
> > --- a/fs/cifs/asn1.c
> > +++ b/fs/cifs/asn1.c
> > @@ -1,612 +1,63 @@
> > // 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;
> > }
> > diff --git a/fs/cifs/spnego_negtokeninit.asn1 b/fs/cifs/spnego_negtokeninit.asn1
> > new file mode 100644
> > index 000000000000..aa5b4a61b3f5
> > --- /dev/null
> > +++ b/fs/cifs/spnego_negtokeninit.asn1
> > @@ -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
> > + }
> > diff --git a/include/linux/oid_registry.h b/include/linux/oid_registry.h
> > index 461b7aa587ba..3d8db1f6a5db 100644
> > --- a/include/linux/oid_registry.h
> > +++ b/include/linux/oid_registry.h
> > @@ -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 */
> > --
> > 2.25.1
> >
>
>
> --
> Thanks,
>
> Steve
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-06-06 7:53 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2021-06-06 1:06 [PATCH v4] cifs: decoding negTokenInit with generic ASN1 decoder Hyunchul Lee
2021-06-06 7:11 ` Steve French
2021-06-06 7:52 ` Hyunchul Lee
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