ociTools: init

1 files changed, 78 insertions, 0 deletions

diff --git a/pkgs/build-support/oci-tools/default.nix b/pkgs/build-support/oci-tools/default.nix
new file mode 100644
index 00000000000..18b238033ff
--- /dev/null
+++ b/pkgs/build-support/oci-tools/default.nix
@@ -0,0 +1,78 @@
+{ lib, writeText, runCommand, writeReferencesToFile }:
+
+{
+  buildContainer =
+    { args
+    , mounts ? {}
+    , os ? "linux"
+    , arch ? "x86_64"
+    , readonly ? false
+    }:
+  let
+    sysMounts = {
+      "/proc" = {
+        type = "proc";
+        source = "proc";
+      };
+      "/dev" = {
+        type = "tmpfs";
+        source = "tmpfs";
+        options = [ "nosuid" "strictatime" "mode=755" "size=65536k" ];
+      };
+      "/dev/pts" = {
+        type = "devpts";
+        source = "devpts";
+        options = [ "nosuid" "noexec" "newinstance" "ptmxmode=0666" "mode=755" "gid=5" ];
+      };
+      "/dev/shm" = {
+        type = "tmpfs";
+        source = "shm";
+        options = [ "nosuid" "noexec" "nodev" "mode=1777" "size=65536k" ];
+      };
+      "/dev/mqueue" = {
+        type = "mqueue";
+        source = "mqueue";
+        options = [ "nosuid" "noexec" "nodev" ];
+      };
+      "/sys" = {
+        type = "sysfs";
+        source = "sysfs";
+        options = [ "nosuid" "noexec" "nodev" "ro" ];
+      };
+      "/sys/fs/cgroup" = {
+        type = "cgroup";
+        source = "cgroup";
+        options = [ "nosuid" "noexec" "nodev" "realatime" "ro" ];
+      };
+    };
+    config = writeText "config.json" (builtins.toJSON {
+      ociVersion = "1.0.0";
+      platform = {
+        inherit os arch;
+      };
+
+      linux = {
+        namespaces = map (type: { inherit type; }) [ "pid" "network" "mount" "ipc" "uts" ];
+      };
+
+      root = { path = "rootfs"; inherit readonly; };
+
+      process = {
+        inherit args;
+        user = { uid = 0; gid = 0; };
+        cwd = "/";
+      };
+
+      mounts = lib.mapAttrsToList (destination: { type, source, options ? null }: {
+        inherit destination type source options;
+      }) sysMounts;
+    });
+  in
+    runCommand "join" {} ''
+      set -o pipefail
+      mkdir -p $out/rootfs/{dev,proc,sys}
+      cp ${config} $out/config.json
+      xargs tar c < ${writeReferencesToFile args} | tar -xC $out/rootfs/
+    '';
+}
+