From: Volker Lendecke <vl@samba.org>
Date: Wed, 21 Dec 2022 15:42:12 +0000 (+0100)
Subject: smbd: Allow symlinks to be read via GET_REPARSE_POINT
X-Git-Tag: tdb-1.4.13~486
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=4a46c6a88273ea765b142299d6cf33d5ec93588a;p=thirdparty%2Fsamba.git

smbd: Allow symlinks to be read via GET_REPARSE_POINT

... to be used soon

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
---

diff --git a/source3/modules/util_reparse.c b/source3/modules/util_reparse.c
index 2694410be4f..60373d7fd4e 100644
--- a/source3/modules/util_reparse.c
+++ b/source3/modules/util_reparse.c
@@ -154,6 +154,45 @@ static NTSTATUS fsctl_get_reparse_point_dev(struct files_struct *fsp,
 		fsp, &reparse_data, ctx, _out_data, max_out_len, _out_len);
 }
 
+static NTSTATUS fsctl_get_reparse_point_lnk(struct files_struct *fsp,
+					    TALLOC_CTX *mem_ctx,
+					    uint8_t **_out_data,
+					    uint32_t max_out_len,
+					    uint32_t *_out_len)
+{
+	struct reparse_data_buffer *reparse = NULL;
+	struct smb_filename *parent_fname = NULL;
+	struct smb_filename *base_name = NULL;
+	NTSTATUS status;
+
+	status = parent_pathref(talloc_tos(),
+				fsp->conn->cwd_fsp,
+				fsp->fsp_name,
+				&parent_fname,
+				&base_name);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("parent_pathref(%s) failed: %s\n",
+			  fsp_str_dbg(fsp),
+			  nt_errstr(status));
+		return status;
+	}
+
+	status = read_symlink_reparse(talloc_tos(),
+				      parent_fname->fsp,
+				      base_name,
+				      &reparse);
+	if (!NT_STATUS_IS_OK(status)) {
+		DBG_DEBUG("read_symlink_reparse failed: %s\n",
+			  nt_errstr(status));
+		return status;
+	}
+
+	status = fsctl_get_reparse_point_int(
+		fsp, reparse, mem_ctx, _out_data, max_out_len, _out_len);
+	TALLOC_FREE(reparse);
+	return status;
+}
+
 NTSTATUS fsctl_get_reparse_point(struct files_struct *fsp,
 				 TALLOC_CTX *mem_ctx,
 				 uint32_t *_reparse_tag,
@@ -212,6 +251,11 @@ NTSTATUS fsctl_get_reparse_point(struct files_struct *fsp,
 			max_out_len,
 			&out_len);
 		break;
+	case S_IFLNK:
+		DBG_DEBUG("%s is a symlink\n", fsp_str_dbg(fsp));
+		status = fsctl_get_reparse_point_lnk(
+			fsp, mem_ctx, &out_data, max_out_len, &out_len);
+		break;
 	default:
 		break;
 	}