Currently SMB client always tries to initialize NetBIOS session when the
server port is 139. This is useful for default cases, but nowadays when
using non-standard routing or testing between VMs, it is common that
servers are listening on non-standard ports.
So add a new mount option -o nbsessinit and -o nonbsessinit which either
forces initialization or disables initialization regardless of server port
number.
This allows Linux SMB client to connect to older SMB1 server listening on
non-standard port, which requires initialization of NetBIOS session, by
using additional mount options -o port= and -o nbsessinit.
Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
---
fs/smb/client/cifsglob.h | 1 +
fs/smb/client/connect.c | 11 ++++++++++-
fs/smb/client/fs_context.c | 14 +++++++++++++-
fs/smb/client/fs_context.h | 2 ++
4 files changed, 26 insertions(+), 2 deletions(-)
diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h
index d4c60d85d7a4..bea4b8a8b30e 100644
--- a/fs/smb/client/cifsglob.h
+++ b/fs/smb/client/cifsglob.h
@@ -716,6 +716,7 @@ struct TCP_Server_Info {
spinlock_t srv_lock; /* protect anything here that is not protected */
__u64 conn_id; /* connection identifier (useful for debugging) */
int srv_count; /* reference counter */
+ int rfc1001_sessinit; /* whether to estasblish netbios session */
/* 15 character server name + 0x20 16th byte indicating type = srv */
char server_RFC1001_name[RFC1001_NAME_LEN_WITH_NULL];
struct smb_version_operations *ops;
diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c
index 20b8bb957468..9cbfdc31cdda 100644
--- a/fs/smb/client/connect.c
+++ b/fs/smb/client/connect.c
@@ -1738,6 +1738,7 @@ cifs_get_tcp_session(struct smb3_fs_context *ctx,
ctx->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
memcpy(tcp_ses->server_RFC1001_name,
ctx->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
+ tcp_ses->rfc1001_sessinit = ctx->rfc1001_sessinit;
tcp_ses->session_estab = false;
tcp_ses->sequence_number = 0;
tcp_ses->channel_sequence_num = 0; /* only tracked for primary channel */
@@ -3206,7 +3207,15 @@ generic_ip_connect(struct TCP_Server_Info *server)
return rc;
}
trace_smb3_connect_done(server->hostname, server->conn_id, &server->dstaddr);
- if (sport == htons(RFC1001_PORT))
+
+ /*
+ * Establish RFC1001 NetBIOS session when it was explicitly requested
+ * by mount option -o nbsessinit, or when connecting to default RFC1001
+ * server port (139) and it was not explicitly disabled by mount option
+ * -o nonbsessinit.
+ */
+ if (server->rfc1001_sessinit == 1 ||
+ (server->rfc1001_sessinit == -1 && sport == htons(RFC1001_PORT)))
rc = ip_rfc1001_connect(server);
return rc;
diff --git a/fs/smb/client/fs_context.c b/fs/smb/client/fs_context.c
index e2ae9819b5ba..3774f02f45c9 100644
--- a/fs/smb/client/fs_context.c
+++ b/fs/smb/client/fs_context.c
@@ -134,6 +134,7 @@ const struct fs_parameter_spec smb3_fs_parameters[] = {
fsparam_flag("compress", Opt_compress),
fsparam_flag("witness", Opt_witness),
fsparam_flag_no("unicode", Opt_unicode),
+ fsparam_flag_no("nbsessinit", Opt_nbsessinit),
/* Mount options which take uid or gid */
fsparam_uid("backupuid", Opt_backupuid),
@@ -965,6 +966,10 @@ static int smb3_verify_reconfigure_ctx(struct fs_context *fc,
cifs_errorf(fc, "can not change unicode during remount\n");
return -EINVAL;
}
+ if (new_ctx->rfc1001_sessinit != old_ctx->rfc1001_sessinit) {
+ cifs_errorf(fc, "can not change nbsessinit during remount\n");
+ return -EINVAL;
+ }
return 0;
}
@@ -1585,6 +1590,10 @@ static int smb3_fs_context_parse_param(struct fs_context *fc,
if (i == RFC1001_NAME_LEN && param->string[i] != 0)
pr_warn("server netbiosname longer than 15 truncated\n");
break;
+ case Opt_nbsessinit:
+ ctx->rfc1001_sessinit = !result.negated;
+ cifs_dbg(FYI, "rfc1001_sessinit set to %d\n", ctx->rfc1001_sessinit);
+ break;
case Opt_ver:
/* version of mount userspace tools, not dialect */
/* If interface changes in mount.cifs bump to new ver */
@@ -1872,13 +1881,16 @@ int smb3_init_fs_context(struct fs_context *fc)
memset(ctx->source_rfc1001_name, 0x20, RFC1001_NAME_LEN);
for (i = 0; i < strnlen(nodename, RFC1001_NAME_LEN); i++)
ctx->source_rfc1001_name[i] = toupper(nodename[i]);
-
ctx->source_rfc1001_name[RFC1001_NAME_LEN] = 0;
+
/*
* null target name indicates to use *SMBSERVR default called name
* if we end up sending RFC1001 session initialize
*/
ctx->target_rfc1001_name[0] = 0;
+
+ ctx->rfc1001_sessinit = -1; /* autodetect based on port number */
+
ctx->cred_uid = current_uid();
ctx->linux_uid = current_uid();
ctx->linux_gid = current_gid();
diff --git a/fs/smb/client/fs_context.h b/fs/smb/client/fs_context.h
index af2d94022a30..e6b22a5fbd0f 100644
--- a/fs/smb/client/fs_context.h
+++ b/fs/smb/client/fs_context.h
@@ -174,6 +174,7 @@ enum cifs_param {
Opt_iocharset,
Opt_netbiosname,
Opt_servern,
+ Opt_nbsessinit,
Opt_ver,
Opt_vers,
Opt_sec,
@@ -216,6 +217,7 @@ struct smb3_fs_context {
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 */
+ int rfc1001_sessinit;
kuid_t cred_uid;
kuid_t linux_uid;
kgid_t linux_gid;
--
2.20.1
