[PATCH 1/1] selinux: Transition to pasta_t in containers

[Max Chernoff <git@maxchernoff.ca>]

Currently, pasta runs in the container_runtime_exec_t context when
running in a container. This is not ideal since it means that pasta runs
with more privileges than strictly necessary. This commit updates the
SELinux policy to have pasta transition to the pasta_t context when
started from the container_runtime_t context, adds the appropriate
labels to $XDG_RUNTIME_DIR/netns and
$XDG_RUNTIME_DIR/containers/networks/rootless-netns, and grants the
necessary permissions to the pasta_t context.

Link: https://bugs.passt.top/show_bug.cgi?id=81
Link: https://github.com/containers/podman/discussions/26100#discussioncomment-13088518
Signed-off-by: Max Chernoff <git@maxchernoff.ca>
---
 contrib/selinux/pasta.fc | 10 ++++++----
 contrib/selinux/pasta.te | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 42 insertions(+), 4 deletions(-)

diff --git a/contrib/selinux/pasta.fc b/contrib/selinux/pasta.fc
index 41ee46d..3be7789 100644
--- a/contrib/selinux/pasta.fc
+++ b/contrib/selinux/pasta.fc
@@ -8,7 +8,9 @@
 # Copyright (c) 2022 Red Hat GmbH
 # Author: Stefano Brivio <sbrivio@redhat.com>
 
-/usr/bin/pasta			system_u:object_r:pasta_exec_t:s0
-/usr/bin/pasta.avx2		system_u:object_r:pasta_exec_t:s0
-/tmp/pasta\.pcap		system_u:object_r:pasta_log_t:s0
-/var/run/pasta\.pid		system_u:object_r:pasta_pid_t:s0
+/usr/bin/pasta			                               system_u:object_r:pasta_exec_t:s0
+/usr/bin/pasta.avx2		                               system_u:object_r:pasta_exec_t:s0
+/tmp/pasta\.pcap		                               system_u:object_r:pasta_log_t:s0
+/var/run/pasta\.pid		                               system_u:object_r:pasta_pid_t:s0
+/run/user/%{USERID}/netns                              system_u:object_r:ifconfig_var_run_t:s0
+/run/user/%{USERID}/containers/networks/rootless-netns system_u:object_r:ifconfig_var_run_t:s0
diff --git a/contrib/selinux/pasta.te b/contrib/selinux/pasta.te
index 89c8043..e97fd88 100644
--- a/contrib/selinux/pasta.te
+++ b/contrib/selinux/pasta.te
@@ -89,6 +89,13 @@ require {
 	class capability { sys_tty_config setuid setgid };
 	class cap_userns { setpcap sys_admin sys_ptrace net_bind_service net_admin };
 	class user_namespace create;
+
+	# Container requires
+	attribute_role usernetctl_roles;
+	role container_user_r;
+	role staff_r;
+	role user_r;
+	type container_runtime_t;
 }
 
 type pasta_t;
@@ -213,3 +220,32 @@ allow pasta_t netutils_t:process { noatsecure rlimitinh siginh };
 allow pasta_t ping_t:process { noatsecure rlimitinh siginh };
 allow pasta_t user_tty_device_t:chr_file { append read write };
 allow pasta_t user_devpts_t:chr_file { append read write };
+
+# Allow network administration commands for non-privileged users
+roleattribute container_user_r usernetctl_roles;
+roleattribute staff_r usernetctl_roles;
+roleattribute user_r usernetctl_roles;
+role usernetctl_roles types pasta_t;
+
+# Make pasta in a container run under the pasta_t context
+type_transition container_runtime_t pasta_exec_t : process pasta_t;
+allow container_runtime_t pasta_t:process transition;
+
+# Label the user network namespace files
+type_transition container_runtime_t user_tmp_t : dir ifconfig_var_run_t "netns";
+type_transition container_runtime_t user_tmp_t : dir ifconfig_var_run_t "rootless-netns";
+allow pasta_t ifconfig_var_run_t:dir { add_name open rmdir write };
+allow pasta_t ifconfig_var_run_t:file { create open write };
+
+# From audit2allow
+allow pasta_t container_runtime_t:fifo_file write;
+allow pasta_t self:cap_userns { setgid setuid };
+allow pasta_t tmpfs_t:filesystem getattr;
+
+# Allow pasta to bind to any port
+bool pasta_allow_bind_any_port true;
+if (pasta_allow_bind_any_port) {
+	allow pasta_t port_type:icmp_socket { accept getopt name_bind };
+	allow pasta_t port_type:tcp_socket { accept getopt name_bind name_connect };
+	allow pasta_t port_type:udp_socket { accept getopt name_bind };
+}
-- 
@@ -89,6 +89,13 @@ require {
 	class capability { sys_tty_config setuid setgid };
 	class cap_userns { setpcap sys_admin sys_ptrace net_bind_service net_admin };
 	class user_namespace create;
+
+	# Container requires
+	attribute_role usernetctl_roles;
+	role container_user_r;
+	role staff_r;
+	role user_r;
+	type container_runtime_t;
 }
 
 type pasta_t;
@@ -213,3 +220,32 @@ allow pasta_t netutils_t:process { noatsecure rlimitinh siginh };
 allow pasta_t ping_t:process { noatsecure rlimitinh siginh };
 allow pasta_t user_tty_device_t:chr_file { append read write };
 allow pasta_t user_devpts_t:chr_file { append read write };
+
+# Allow network administration commands for non-privileged users
+roleattribute container_user_r usernetctl_roles;
+roleattribute staff_r usernetctl_roles;
+roleattribute user_r usernetctl_roles;
+role usernetctl_roles types pasta_t;
+
+# Make pasta in a container run under the pasta_t context
+type_transition container_runtime_t pasta_exec_t : process pasta_t;
+allow container_runtime_t pasta_t:process transition;
+
+# Label the user network namespace files
+type_transition container_runtime_t user_tmp_t : dir ifconfig_var_run_t "netns";
+type_transition container_runtime_t user_tmp_t : dir ifconfig_var_run_t "rootless-netns";
+allow pasta_t ifconfig_var_run_t:dir { add_name open rmdir write };
+allow pasta_t ifconfig_var_run_t:file { create open write };
+
+# From audit2allow
+allow pasta_t container_runtime_t:fifo_file write;
+allow pasta_t self:cap_userns { setgid setuid };
+allow pasta_t tmpfs_t:filesystem getattr;
+
+# Allow pasta to bind to any port
+bool pasta_allow_bind_any_port true;
+if (pasta_allow_bind_any_port) {
+	allow pasta_t port_type:icmp_socket { accept getopt name_bind };
+	allow pasta_t port_type:tcp_socket { accept getopt name_bind name_connect };
+	allow pasta_t port_type:udp_socket { accept getopt name_bind };
+}
-- 
2.49.0