From: Jo-Philipp Wich <jo@mein.io>
Date: Fri, 13 Sep 2019 04:52:21 +0000 (+0200)
Subject: cgi-io: use different acl scopes for path and command permissions
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=0fc83858fc280b61980cd859704a039596a0e8bb;p=feed%2Fpackages.git

cgi-io: use different acl scopes for path and command permissions

Use the `cgi-io` scope to check for permission to execute the requested
command (`upload`, `backup`) and the `file` scope to check path
permissions.

The reasoning of this change is that `cgi-io` is usually used in
conjunction with `rpcd-mod-file` to transfer large file data out
of band and `rpcd-mod-file` already uses the `file` scope to manage
file path access permissions. After this change, both `rpc-mod-file`
and `cgi-io` can share the same path acl rules.

Write access to a path can be granted by using an ubus call in the
following form:

    ubus call session grant '{
        "ubus_rpc_session": "...",
        "scope": "file",
        "objects": [
            [ "/var/lib/uploads/*", "write" ]
        ]
    }'

Signed-off-by: Jo-Philipp Wich <jo@mein.io>
(cherry picked from commit c8a86c8c8e1925eb7d84c52e702c4be5fc8ac76b)
---

diff --git a/net/cgi-io/Makefile b/net/cgi-io/Makefile
index 3a4fc565f9..4b2d664af9 100644
--- a/net/cgi-io/Makefile
+++ b/net/cgi-io/Makefile
@@ -8,7 +8,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=cgi-io
-PKG_RELEASE:=7
+PKG_RELEASE:=9
 
 PKG_LICENSE:=GPL-2.0-or-later
 
diff --git a/net/cgi-io/src/main.c b/net/cgi-io/src/main.c
index a6ded065f4..44a5205760 100644
--- a/net/cgi-io/src/main.c
+++ b/net/cgi-io/src/main.c
@@ -89,7 +89,7 @@ session_access_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 }
 
 static bool
-session_access(const char *sid, const char *obj, const char *func)
+session_access(const char *sid, const char *scope, const char *obj, const char *func)
 {
 	uint32_t id;
 	bool allow = false;
@@ -103,7 +103,7 @@ session_access(const char *sid, const char *obj, const char *func)
 
 	blob_buf_init(&req, 0);
 	blobmsg_add_string(&req, "ubus_rpc_session", sid);
-	blobmsg_add_string(&req, "scope", "cgi-io");
+	blobmsg_add_string(&req, "scope", scope);
 	blobmsg_add_string(&req, "object", obj);
 	blobmsg_add_string(&req, "function", func);
 
@@ -475,7 +475,7 @@ data_begin_cb(multipart_parser *p)
 		if (!st.filename)
 			return response(false, "File data without name");
 
-		if (!session_access(st.sessionid, st.filename, "write"))
+		if (!session_access(st.sessionid, "file", st.filename, "write"))
 			return response(false, "Access to path denied by ACL");
 
 		st.tempfd = mkstemp(tmpname);
@@ -530,7 +530,7 @@ data_end_cb(multipart_parser *p)
 {
 	if (st.parttype == PART_SESSIONID)
 	{
-		if (!session_access(st.sessionid, "upload", "write"))
+		if (!session_access(st.sessionid, "cgi-io", "upload", "write"))
 		{
 			errno = EPERM;
 			return response(false, "Upload permission denied");
@@ -658,7 +658,7 @@ main_backup(int argc, char **argv)
 	char hostname[64] = { 0 };
 	char *fields[] = { "sessionid", NULL };
 
-	if (!postdecode(fields, 1) || !session_access(fields[1], "backup", "read"))
+	if (!postdecode(fields, 1) || !session_access(fields[1], "cgi-io", "backup", "read"))
 		return failure(0, "Backup permission denied");
 
 	if (pipe(fds))