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path: root/fs/cifs/smb2pdu.c
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Diffstat (limited to 'fs/cifs/smb2pdu.c')
-rw-r--r--fs/cifs/smb2pdu.c111
1 files changed, 93 insertions, 18 deletions
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 5531e7ee1210..6f0e6343c15e 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -439,7 +439,7 @@ assemble_neg_contexts(struct smb2_negotiate_req *req)
build_encrypt_ctxt((struct smb2_encryption_neg_context *)pneg_ctxt);
req->NegotiateContextOffset = cpu_to_le32(OFFSET_OF_NEG_CONTEXT);
req->NegotiateContextCount = cpu_to_le16(2);
- inc_rfc1001_len(req, 4 + sizeof(struct smb2_preauth_neg_context) + 2
+ inc_rfc1001_len(req, 4 + sizeof(struct smb2_preauth_neg_context)
+ sizeof(struct smb2_encryption_neg_context)); /* calculate hash */
}
#else
@@ -491,10 +491,25 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
req->hdr.sync_hdr.SessionId = 0;
- req->Dialects[0] = cpu_to_le16(ses->server->vals->protocol_id);
-
- req->DialectCount = cpu_to_le16(1); /* One vers= at a time for now */
- inc_rfc1001_len(req, 2);
+ if (strcmp(ses->server->vals->version_string,
+ SMB3ANY_VERSION_STRING) == 0) {
+ req->Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
+ req->Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
+ req->DialectCount = cpu_to_le16(2);
+ inc_rfc1001_len(req, 4);
+ } else if (strcmp(ses->server->vals->version_string,
+ SMBDEFAULT_VERSION_STRING) == 0) {
+ req->Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
+ req->Dialects[1] = cpu_to_le16(SMB30_PROT_ID);
+ req->Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
+ req->DialectCount = cpu_to_le16(3);
+ inc_rfc1001_len(req, 6);
+ } else {
+ /* otherwise send specific dialect */
+ req->Dialects[0] = cpu_to_le16(ses->server->vals->protocol_id);
+ req->DialectCount = cpu_to_le16(1);
+ inc_rfc1001_len(req, 2);
+ }
/* only one of SMB2 signing flags may be set in SMB2 request */
if (ses->sign)
@@ -528,16 +543,43 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
*/
if (rc == -EOPNOTSUPP) {
cifs_dbg(VFS, "Dialect not supported by server. Consider "
- "specifying vers=1.0 or vers=2.1 on mount for accessing"
+ "specifying vers=1.0 or vers=2.0 on mount for accessing"
" older servers\n");
goto neg_exit;
} else if (rc != 0)
goto neg_exit;
+ if (strcmp(ses->server->vals->version_string,
+ SMB3ANY_VERSION_STRING) == 0) {
+ if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID)) {
+ cifs_dbg(VFS,
+ "SMB2 dialect returned but not requested\n");
+ return -EIO;
+ } else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID)) {
+ cifs_dbg(VFS,
+ "SMB2.1 dialect returned but not requested\n");
+ return -EIO;
+ }
+ } else if (strcmp(ses->server->vals->version_string,
+ SMBDEFAULT_VERSION_STRING) == 0) {
+ if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID)) {
+ cifs_dbg(VFS,
+ "SMB2 dialect returned but not requested\n");
+ return -EIO;
+ } else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID)) {
+ /* ops set to 3.0 by default for default so update */
+ ses->server->ops = &smb21_operations;
+ }
+ } else if (le16_to_cpu(rsp->DialectRevision) !=
+ ses->server->vals->protocol_id) {
+ /* if requested single dialect ensure returned dialect matched */
+ cifs_dbg(VFS, "Illegal 0x%x dialect returned: not requested\n",
+ le16_to_cpu(rsp->DialectRevision));
+ return -EIO;
+ }
+
cifs_dbg(FYI, "mode 0x%x\n", rsp->SecurityMode);
- /* BB we may eventually want to match the negotiated vs. requested
- dialect, even though we are only requesting one at a time */
if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID))
cifs_dbg(FYI, "negotiated smb2.0 dialect\n");
else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID))
@@ -558,6 +600,8 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
}
server->dialect = le16_to_cpu(rsp->DialectRevision);
+ /* BB: add check that dialect was valid given dialect(s) we asked for */
+
/* SMB2 only has an extended negflavor */
server->negflavor = CIFS_NEGFLAVOR_EXTENDED;
/* set it to the maximum buffer size value we can send with 1 credit */
@@ -606,20 +650,28 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
struct validate_negotiate_info_req vneg_inbuf;
struct validate_negotiate_info_rsp *pneg_rsp;
u32 rsplen;
+ u32 inbuflen; /* max of 4 dialects */
cifs_dbg(FYI, "validate negotiate\n");
/*
* validation ioctl must be signed, so no point sending this if we
- * can not sign it. We could eventually change this to selectively
+ * can not sign it (ie are not known user). Even if signing is not
+ * required (enabled but not negotiated), in those cases we selectively
* sign just this, the first and only signed request on a connection.
- * This is good enough for now since a user who wants better security
- * would also enable signing on the mount. Having validation of
- * negotiate info for signed connections helps reduce attack vectors
+ * Having validation of negotiate info helps reduce attack vectors.
*/
- if (tcon->ses->server->sign == false)
+ if (tcon->ses->session_flags & SMB2_SESSION_FLAG_IS_GUEST)
return 0; /* validation requires signing */
+ if (tcon->ses->user_name == NULL) {
+ cifs_dbg(FYI, "Can't validate negotiate: null user mount\n");
+ return 0; /* validation requires signing */
+ }
+
+ if (tcon->ses->session_flags & SMB2_SESSION_FLAG_IS_NULL)
+ cifs_dbg(VFS, "Unexpected null user (anonymous) auth flag sent by server\n");
+
vneg_inbuf.Capabilities =
cpu_to_le32(tcon->ses->server->vals->req_capabilities);
memcpy(vneg_inbuf.Guid, tcon->ses->server->client_guid,
@@ -634,9 +686,30 @@ int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
else
vneg_inbuf.SecurityMode = 0;
- vneg_inbuf.DialectCount = cpu_to_le16(1);
- vneg_inbuf.Dialects[0] =
- cpu_to_le16(tcon->ses->server->vals->protocol_id);
+
+ if (strcmp(tcon->ses->server->vals->version_string,
+ SMB3ANY_VERSION_STRING) == 0) {
+ vneg_inbuf.Dialects[0] = cpu_to_le16(SMB30_PROT_ID);
+ vneg_inbuf.Dialects[1] = cpu_to_le16(SMB302_PROT_ID);
+ vneg_inbuf.DialectCount = cpu_to_le16(2);
+ /* structure is big enough for 3 dialects, sending only 2 */
+ inbuflen = sizeof(struct validate_negotiate_info_req) - 2;
+ } else if (strcmp(tcon->ses->server->vals->version_string,
+ SMBDEFAULT_VERSION_STRING) == 0) {
+ vneg_inbuf.Dialects[0] = cpu_to_le16(SMB21_PROT_ID);
+ vneg_inbuf.Dialects[1] = cpu_to_le16(SMB30_PROT_ID);
+ vneg_inbuf.Dialects[2] = cpu_to_le16(SMB302_PROT_ID);
+ vneg_inbuf.DialectCount = cpu_to_le16(3);
+ /* structure is big enough for 3 dialects */
+ inbuflen = sizeof(struct validate_negotiate_info_req);
+ } else {
+ /* otherwise specific dialect was requested */
+ vneg_inbuf.Dialects[0] =
+ cpu_to_le16(tcon->ses->server->vals->protocol_id);
+ vneg_inbuf.DialectCount = cpu_to_le16(1);
+ /* structure is big enough for 3 dialects, sending only 1 */
+ inbuflen = sizeof(struct validate_negotiate_info_req) - 4;
+ }
rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID,
FSCTL_VALIDATE_NEGOTIATE_INFO, true /* is_fsctl */,
@@ -1110,6 +1183,8 @@ SMB2_sess_setup(const unsigned int xid, struct cifs_ses *ses,
while (sess_data->func)
sess_data->func(sess_data);
+ if ((ses->session_flags & SMB2_SESSION_FLAG_IS_GUEST) && (ses->sign))
+ cifs_dbg(VFS, "signing requested but authenticated as guest\n");
rc = sess_data->result;
out:
kfree(sess_data);
@@ -1634,7 +1709,7 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
struct cifs_tcon *tcon = oparms->tcon;
struct cifs_ses *ses = tcon->ses;
struct kvec iov[4];
- struct kvec rsp_iov;
+ struct kvec rsp_iov = {NULL, 0};
int resp_buftype;
int uni_path_len;
__le16 *copy_path = NULL;
@@ -1763,7 +1838,7 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
if (rc != 0) {
cifs_stats_fail_inc(tcon, SMB2_CREATE_HE);
- if (err_buf)
+ if (err_buf && rsp)
*err_buf = kmemdup(rsp, get_rfc1002_length(rsp) + 4,
GFP_KERNEL);
goto creat_exit;
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-23 03:05:37 +0300