s3: client: Add new utility function client_clean_name().

Correctly canonicalizes a remote pathname removing '..'
elements before sending to a remote server. '..' elements
work in SMB1 pathnames, but not in SMB2.

Not yet used.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13093

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Andreas Schneider <asn@samba.org>

2 files changed, 32 insertions, 0 deletions

diff --git a/source3/client/client.c b/source3/client/client.c
index df16496ff86..8cc511983cb 100644
--- a/source3/client/client.c
+++ b/source3/client/client.c
@@ -346,6 +346,37 @@ static void normalize_name(char *newdir)
 }
 
 /****************************************************************************
+ Local name cleanup before sending to server. SMB1 allows relative pathnames,
+ but SMB2 does not, so we need to resolve them locally.
+****************************************************************************/
+
+char *client_clean_name(TALLOC_CTX *ctx, const char *name)
+{
+	char *newname = NULL;
+	if (name == NULL) {
+		return NULL;
+	}
+
+	/* First ensure any path separators are correct. */
+	newname = talloc_strdup(ctx, name);
+	if (newname == NULL) {
+		return NULL;
+	}
+	normalize_name(newname);
+
+	/* Now remove any relative (..) path components. */
+	if (cli->requested_posix_capabilities & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
+		newname = unix_clean_name(ctx, newname);
+	} else {
+		newname = clean_name(ctx, newname);
+	}
+	if (newname == NULL) {
+		return NULL;
+	}
+	return newname;
+}
+
+/****************************************************************************
  Change directory - inner section.
 ****************************************************************************/
 
diff --git a/source3/client/client_proto.h b/source3/client/client_proto.h
index d3d40363f20..38f13aa0adc 100644
--- a/source3/client/client_proto.h
+++ b/source3/client/client_proto.h
@@ -35,6 +35,7 @@ enum {
 
 const char *client_get_cur_dir(void);
 const char *client_set_cur_dir(const char *newdir);
+char *client_clean_name(TALLOC_CTX *ctx, const char *name);
 NTSTATUS do_list(const char *mask,
 			uint16_t attribute,
 			NTSTATUS (*fn)(struct cli_state *cli_state, struct file_info *,