From ca085a95e36e0cdda56a553f3f7894a30db127b6 Mon Sep 17 00:00:00 2001
From: Shyam Prasad N <sprasad@microsoft.com>
Date: Fri, 5 Nov 2021 19:03:57 +0000
Subject: [PATCH] cifs: send workstation name during ntlmssp session setup
During the ntlmssp session setup (authenticate phases)
send the client workstation info. This can make debugging easier on
servers.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
---
fs/cifs/cifsglob.h | 4 +
fs/cifs/connect.c | 6 ++
fs/cifs/fs_context.c | 34 +++++++-
fs/cifs/fs_context.h | 1 +
fs/cifs/misc.c | 1 +
fs/cifs/ntlmssp.h | 4 +-
fs/cifs/sess.c | 188 +++++++++++++++++++++++++++----------------
fs/cifs/smb2pdu.c | 17 ++--
8 files changed, 170 insertions(+), 85 deletions(-)
@@ -15,6 +15,7 @@
#include <linux/slab.h>
#include <linux/mempool.h>
#include <linux/workqueue.h>
+#include <linux/utsname.h>
#include "cifs_fs_sb.h"
#include "cifsacl.h"
#include <crypto/internal/hash.h>
@@ -99,6 +100,8 @@
#define XATTR_DOS_ATTRIB "user.DOSATTRIB"
#endif
+#define CIFS_MAX_WORKSTATION_LEN (__NEW_UTS_LEN + 1) /* reasonable max for client */
+
/*
* CIFS vfs client Status information (based on what we know.)
*/
@@ -909,6 +912,7 @@ struct cifs_ses {
and after mount option parsing we fill it */
char *domainName;
char *password;
+ char *workstation_name;
struct session_key auth_key;
struct ntlmssp_auth *ntlmssp; /* ciphertext, flags, server challenge */
enum securityEnum sectype; /* what security flavor was specified? */
@@ -1948,6 +1948,12 @@ cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
if (!ses->domainName)
goto get_ses_fail;
}
+ if (ctx->workstation_name) {
+ ses->workstation_name = kstrdup(ctx->workstation_name,
+ GFP_KERNEL);
+ if (!ses->workstation_name)
+ goto get_ses_fail;
+ }
if (ctx->domainauto)
ses->domainAuto = ctx->domainauto;
ses->cred_uid = ctx->cred_uid;
@@ -309,6 +309,7 @@ smb3_fs_context_dup(struct smb3_fs_context *new_ctx, struct smb3_fs_context *ctx
new_ctx->username = NULL;
new_ctx->password = NULL;
new_ctx->domainname = NULL;
+ new_ctx->workstation_name = NULL;
new_ctx->UNC = NULL;
new_ctx->source = NULL;
new_ctx->iocharset = NULL;
@@ -323,6 +324,7 @@ smb3_fs_context_dup(struct smb3_fs_context *new_ctx, struct smb3_fs_context *ctx
DUP_CTX_STR(UNC);
DUP_CTX_STR(source);
DUP_CTX_STR(domainname);
+ DUP_CTX_STR(workstation_name);
DUP_CTX_STR(nodename);
DUP_CTX_STR(iocharset);
@@ -720,6 +722,11 @@ static int smb3_verify_reconfigure_ctx(struct fs_context *fc,
cifs_errorf(fc, "can not change domainname during remount\n");
return -EINVAL;
}
+ if (new_ctx->workstation_name &&
+ (!old_ctx->workstation_name || strcmp(new_ctx->workstation_name, old_ctx->workstation_name))) {
+ cifs_errorf(fc, "can not change workstation_name during remount\n");
+ return -EINVAL;
+ }
if (new_ctx->nodename &&
(!old_ctx->nodename || strcmp(new_ctx->nodename, old_ctx->nodename))) {
cifs_errorf(fc, "can not change nodename during remount\n");
@@ -753,7 +760,8 @@ static int smb3_reconfigure(struct fs_context *fc)
return rc;
/*
- * We can not change UNC/username/password/domainname/nodename/iocharset
+ * We can not change UNC/username/password/domainname/
+ * workstation_name/nodename/iocharset
* during reconnect so ignore what we have in the new context and
* just use what we already have in cifs_sb->ctx.
*/
@@ -762,6 +770,7 @@ static int smb3_reconfigure(struct fs_context *fc)
STEAL_STRING(cifs_sb, ctx, username);
STEAL_STRING(cifs_sb, ctx, password);
STEAL_STRING(cifs_sb, ctx, domainname);
+ STEAL_STRING(cifs_sb, ctx, workstation_name);
STEAL_STRING(cifs_sb, ctx, nodename);
STEAL_STRING(cifs_sb, ctx, iocharset);
@@ -1414,13 +1423,22 @@ static int smb3_fs_context_parse_param(struct fs_context *fc,
int smb3_init_fs_context(struct fs_context *fc)
{
+ int rc;
struct smb3_fs_context *ctx;
char *nodename = utsname()->nodename;
int i;
ctx = kzalloc(sizeof(struct smb3_fs_context), GFP_KERNEL);
- if (unlikely(!ctx))
- return -ENOMEM;
+ if (unlikely(!ctx)) {
+ rc = -ENOMEM;
+ goto err_exit;
+ }
+
+ ctx->workstation_name = kstrdup(nodename, GFP_KERNEL);
+ if (unlikely(!ctx->workstation_name)) {
+ rc = -ENOMEM;
+ goto err_exit;
+ }
/*
* does not have to be perfect mapping since field is
@@ -1493,6 +1511,14 @@ int smb3_init_fs_context(struct fs_context *fc)
fc->fs_private = ctx;
fc->ops = &smb3_fs_context_ops;
return 0;
+
+err_exit:
+ if (ctx) {
+ kfree(ctx->workstation_name);
+ kfree(ctx);
+ }
+
+ return rc;
}
void
@@ -1518,6 +1544,8 @@ smb3_cleanup_fs_context_contents(struct smb3_fs_context *ctx)
ctx->source = NULL;
kfree(ctx->domainname);
ctx->domainname = NULL;
+ kfree(ctx->workstation_name);
+ ctx->workstation_name = NULL;
kfree(ctx->nodename);
ctx->nodename = NULL;
kfree(ctx->iocharset);
@@ -170,6 +170,7 @@ struct smb3_fs_context {
char *server_hostname;
char *UNC;
char *nodename;
+ char *workstation_name;
char *iocharset; /* local code page for mapping to and from Unicode */
char source_rfc1001_name[RFC1001_NAME_LEN_WITH_NULL]; /* clnt nb name */
char target_rfc1001_name[RFC1001_NAME_LEN_WITH_NULL]; /* srvr nb name */
@@ -94,6 +94,7 @@ sesInfoFree(struct cifs_ses *buf_to_free)
kfree_sensitive(buf_to_free->password);
kfree(buf_to_free->user_name);
kfree(buf_to_free->domainName);
+ kfree(buf_to_free->workstation_name);
kfree_sensitive(buf_to_free->auth_key.response);
kfree(buf_to_free->iface_list);
kfree_sensitive(buf_to_free);
@@ -119,7 +119,9 @@ typedef struct _AUTHENTICATE_MESSAGE {
*/
int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len, struct cifs_ses *ses);
-void build_ntlmssp_negotiate_blob(unsigned char *pbuffer, struct cifs_ses *ses);
+int build_ntlmssp_negotiate_blob(unsigned char **pbuffer, u16 *buflen,
+ struct cifs_ses *ses,
+ const struct nls_table *nls_cp);
int build_ntlmssp_auth_blob(unsigned char **pbuffer, u16 *buflen,
struct cifs_ses *ses,
const struct nls_table *nls_cp);
@@ -599,18 +599,85 @@ int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
return 0;
}
+static int size_of_ntlmssp_blob(struct cifs_ses *ses, int base_size)
+{
+ int sz = base_size + ses->auth_key.len
+ - CIFS_SESS_KEY_SIZE + CIFS_CPHTXT_SIZE + 2;
+
+ if (ses->domainName)
+ sz += sizeof(__le16) * strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
+ else
+ sz += sizeof(__le16);
+
+ if (ses->user_name)
+ sz += sizeof(__le16) * strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
+ else
+ sz += sizeof(__le16);
+
+ sz += sizeof(__le16) * strnlen(ses->workstation_name, CIFS_MAX_WORKSTATION_LEN);
+
+ return sz;
+}
+
+static inline void cifs_security_buffer_from_str(SECURITY_BUFFER *pbuf,
+ char *str_value,
+ int str_length,
+ unsigned char *pstart,
+ unsigned char **pcur,
+ const struct nls_table *nls_cp)
+{
+ unsigned char *tmp = pstart;
+ int len;
+
+ if (!pbuf)
+ return;
+
+ if (!pcur)
+ pcur = &tmp;
+
+ if (!str_value) {
+ pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
+ pbuf->Length = 0;
+ pbuf->MaximumLength = 0;
+ *pcur += sizeof(__le16);
+ } else {
+ len = cifs_strtoUTF16((__le16 *)*pcur,
+ str_value,
+ str_length,
+ nls_cp);
+ len *= sizeof(__le16);
+ pbuf->BufferOffset = cpu_to_le32(*pcur - pstart);
+ pbuf->Length = cpu_to_le16(len);
+ pbuf->MaximumLength = cpu_to_le16(len);
+ *pcur += len;
+ }
+}
+
/* BB Move to ntlmssp.c eventually */
-/* We do not malloc the blob, it is passed in pbuffer, because
- it is fixed size, and small, making this approach cleaner */
-void build_ntlmssp_negotiate_blob(unsigned char *pbuffer,
- struct cifs_ses *ses)
+int build_ntlmssp_negotiate_blob(unsigned char **pbuffer,
+ u16 *buflen,
+ struct cifs_ses *ses,
+ const struct nls_table *nls_cp)
{
+ int rc = 0;
struct TCP_Server_Info *server = cifs_ses_server(ses);
- NEGOTIATE_MESSAGE *sec_blob = (NEGOTIATE_MESSAGE *)pbuffer;
+ NEGOTIATE_MESSAGE *sec_blob;
__u32 flags;
+ unsigned char *tmp;
+ int len;
+
+ len = size_of_ntlmssp_blob(ses, sizeof(NEGOTIATE_MESSAGE));
+ *pbuffer = kmalloc(len, GFP_KERNEL);
+ if (!*pbuffer) {
+ rc = -ENOMEM;
+ cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
+ *buflen = 0;
+ goto setup_ntlm_neg_ret;
+ }
+ sec_blob = (NEGOTIATE_MESSAGE *)*pbuffer;
- memset(pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
+ memset(*pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
sec_blob->MessageType = NtLmNegotiate;
@@ -624,34 +691,25 @@ void build_ntlmssp_negotiate_blob(unsigned char *pbuffer,
if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
+ tmp = *pbuffer + sizeof(NEGOTIATE_MESSAGE);
sec_blob->NegotiateFlags = cpu_to_le32(flags);
- sec_blob->WorkstationName.BufferOffset = 0;
- sec_blob->WorkstationName.Length = 0;
- sec_blob->WorkstationName.MaximumLength = 0;
-
- /* Domain name is sent on the Challenge not Negotiate NTLMSSP request */
- sec_blob->DomainName.BufferOffset = 0;
- sec_blob->DomainName.Length = 0;
- sec_blob->DomainName.MaximumLength = 0;
-}
-
-static int size_of_ntlmssp_blob(struct cifs_ses *ses)
-{
- int sz = sizeof(AUTHENTICATE_MESSAGE) + ses->auth_key.len
- - CIFS_SESS_KEY_SIZE + CIFS_CPHTXT_SIZE + 2;
-
- if (ses->domainName)
- sz += 2 * strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
- else
- sz += 2;
+ /* these fields should be null in negotiate phase MS-NLMP 3.1.5.1.1 */
+ cifs_security_buffer_from_str(&sec_blob->DomainName,
+ NULL,
+ CIFS_MAX_DOMAINNAME_LEN,
+ *pbuffer, &tmp,
+ nls_cp);
- if (ses->user_name)
- sz += 2 * strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
- else
- sz += 2;
+ cifs_security_buffer_from_str(&sec_blob->WorkstationName,
+ NULL,
+ CIFS_MAX_WORKSTATION_LEN,
+ *pbuffer, &tmp,
+ nls_cp);
- return sz;
+ *buflen = tmp - *pbuffer;
+setup_ntlm_neg_ret:
+ return rc;
}
int build_ntlmssp_auth_blob(unsigned char **pbuffer,
@@ -663,6 +721,7 @@ int build_ntlmssp_auth_blob(unsigned char **pbuffer,
AUTHENTICATE_MESSAGE *sec_blob;
__u32 flags;
unsigned char *tmp;
+ int len;
rc = setup_ntlmv2_rsp(ses, nls_cp);
if (rc) {
@@ -670,7 +729,9 @@ int build_ntlmssp_auth_blob(unsigned char **pbuffer,
*buflen = 0;
goto setup_ntlmv2_ret;
}
- *pbuffer = kmalloc(size_of_ntlmssp_blob(ses), GFP_KERNEL);
+
+ len = size_of_ntlmssp_blob(ses, sizeof(AUTHENTICATE_MESSAGE));
+ *pbuffer = kmalloc(len, GFP_KERNEL);
if (!*pbuffer) {
rc = -ENOMEM;
cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
@@ -686,7 +747,7 @@ int build_ntlmssp_auth_blob(unsigned char **pbuffer,
NTLMSSP_REQUEST_TARGET | NTLMSSP_NEGOTIATE_TARGET_INFO |
NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
- NTLMSSP_NEGOTIATE_SEAL;
+ NTLMSSP_NEGOTIATE_SEAL | NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED;
if (ses->server->sign)
flags |= NTLMSSP_NEGOTIATE_SIGN;
if (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
@@ -719,42 +780,23 @@ int build_ntlmssp_auth_blob(unsigned char **pbuffer,
sec_blob->NtChallengeResponse.MaximumLength = 0;
}
- if (ses->domainName == NULL) {
- sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - *pbuffer);
- sec_blob->DomainName.Length = 0;
- sec_blob->DomainName.MaximumLength = 0;
- tmp += 2;
- } else {
- int len;
- len = cifs_strtoUTF16((__le16 *)tmp, ses->domainName,
- CIFS_MAX_DOMAINNAME_LEN, nls_cp);
- len *= 2; /* unicode is 2 bytes each */
- sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - *pbuffer);
- sec_blob->DomainName.Length = cpu_to_le16(len);
- sec_blob->DomainName.MaximumLength = cpu_to_le16(len);
- tmp += len;
- }
+ cifs_security_buffer_from_str(&sec_blob->DomainName,
+ ses->domainName,
+ CIFS_MAX_DOMAINNAME_LEN,
+ *pbuffer, &tmp,
+ nls_cp);
- if (ses->user_name == NULL) {
- sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - *pbuffer);
- sec_blob->UserName.Length = 0;
- sec_blob->UserName.MaximumLength = 0;
- tmp += 2;
- } else {
- int len;
- len = cifs_strtoUTF16((__le16 *)tmp, ses->user_name,
- CIFS_MAX_USERNAME_LEN, nls_cp);
- len *= 2; /* unicode is 2 bytes each */
- sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - *pbuffer);
- sec_blob->UserName.Length = cpu_to_le16(len);
- sec_blob->UserName.MaximumLength = cpu_to_le16(len);
- tmp += len;
- }
+ cifs_security_buffer_from_str(&sec_blob->UserName,
+ ses->user_name,
+ CIFS_MAX_USERNAME_LEN,
+ *pbuffer, &tmp,
+ nls_cp);
- sec_blob->WorkstationName.BufferOffset = cpu_to_le32(tmp - *pbuffer);
- sec_blob->WorkstationName.Length = 0;
- sec_blob->WorkstationName.MaximumLength = 0;
- tmp += 2;
+ cifs_security_buffer_from_str(&sec_blob->WorkstationName,
+ ses->workstation_name,
+ CIFS_MAX_WORKSTATION_LEN,
+ *pbuffer, &tmp,
+ nls_cp);
if (((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) ||
(ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC))
@@ -1230,6 +1272,7 @@ sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
struct cifs_ses *ses = sess_data->ses;
__u16 bytes_remaining;
char *bcc_ptr;
+ unsigned char *ntlmsspblob = NULL;
u16 blob_len;
cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
@@ -1253,10 +1296,15 @@ sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
/* Build security blob before we assemble the request */
- build_ntlmssp_negotiate_blob(pSMB->req.SecurityBlob, ses);
- sess_data->iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
- sess_data->iov[1].iov_base = pSMB->req.SecurityBlob;
- pSMB->req.SecurityBlobLength = cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
+ rc = build_ntlmssp_negotiate_blob(&ntlmsspblob,
+ &blob_len, ses,
+ sess_data->nls_cp);
+ if (rc)
+ goto out;
+
+ sess_data->iov[1].iov_len = blob_len;
+ sess_data->iov[1].iov_base = ntlmsspblob;
+ pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
if (rc)
@@ -1456,7 +1456,7 @@ SMB2_sess_auth_rawntlmssp_negotiate(struct SMB2_sess_data *sess_data)
int rc;
struct cifs_ses *ses = sess_data->ses;
struct smb2_sess_setup_rsp *rsp = NULL;
- char *ntlmssp_blob = NULL;
+ unsigned char *ntlmssp_blob = NULL;
bool use_spnego = false; /* else use raw ntlmssp */
u16 blob_length = 0;
@@ -1475,22 +1475,17 @@ SMB2_sess_auth_rawntlmssp_negotiate(struct SMB2_sess_data *sess_data)
if (rc)
goto out_err;
- ntlmssp_blob = kmalloc(sizeof(struct _NEGOTIATE_MESSAGE),
- GFP_KERNEL);
- if (ntlmssp_blob == NULL) {
- rc = -ENOMEM;
- goto out;
- }
+ rc = build_ntlmssp_negotiate_blob(&ntlmssp_blob,
+ &blob_length, ses,
+ sess_data->nls_cp);
+ if (rc)
+ goto out_err;
- build_ntlmssp_negotiate_blob(ntlmssp_blob, ses);
if (use_spnego) {
/* BB eventually need to add this */
cifs_dbg(VFS, "spnego not supported for SMB2 yet\n");
rc = -EOPNOTSUPP;
goto out;
- } else {
- blob_length = sizeof(struct _NEGOTIATE_MESSAGE);
- /* with raw NTLMSSP we don't encapsulate in SPNEGO */
}
sess_data->iov[1].iov_base = ntlmssp_blob;
sess_data->iov[1].iov_len = blob_length;
--
2.32.0