security/fortify
2
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases 18 Wiki Activity

app/share: fix order to ensure SharePath before any of its subdirectories

Browse Source 
shareTmpdirChild happened to request an ephemeral dir within SharePath and was called before shareRuntime which ensures that path. This commit moves SharePath initialisation to shareSystem and moves shareTmpdirChild into ShareSystem. Further cleanup and tests are desperately needed for the app package but for now this fix will have to do.

Signed-off-by: Ophestra Umiker <cat@ophivana.moe>
This commit is contained in:
Ophestra 2024-10-18 01:21:58 +09:00
parent 4ebb98649e
commit 65bd7d18db
Signed by: cat
SSH Key Fingerprint: SHA256:gQ67O0enBZ7UdZypgtspB2FDM1g3GVw8nX0XSdcFw8Q
3 changed files with 27 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
internal/app/share.runtime.go
View File

@ -31,15 +31,6 @@ func (seal *appSeal) shareRuntime() {
// ensure runtime directory ACL (e.g. `/run/user/%d`)
seal.sys.UpdatePermType(system.User, seal.RuntimePath, acl.Execute)
// ensure Share (e.g. `/tmp/fortify.%d`)
// acl is unnecessary as this directory is world executable
seal.sys.Ensure(seal.SharePath, 0701)
// ensure process-specific share (e.g. `/tmp/fortify.%d/%s`)
// acl is unnecessary as this directory is world executable
seal.share = path.Join(seal.SharePath, seal.id.String())
seal.sys.Ephemeral(system.Process, seal.share, 0701)
// ensure process-specific share local to XDG_RUNTIME_DIR (e.g. `/run/user/%d/fortify/%s`)
seal.shareLocal = path.Join(seal.RunDirPath, seal.id.String())
seal.sys.Ephemeral(system.Process, seal.shareLocal, 0700)

43
internal/app/share.system.go
View File

@ -14,6 +14,31 @@ const (
// shareSystem queues various system-related actions
func (seal *appSeal) shareSystem() {
// ensure Share (e.g. `/tmp/fortify.%d`)
// acl is unnecessary as this directory is world executable
seal.sys.Ensure(seal.SharePath, 0701)
// ensure process-specific share (e.g. `/tmp/fortify.%d/%s`)
// acl is unnecessary as this directory is world executable
seal.share = path.Join(seal.SharePath, seal.id.String())
seal.sys.Ephemeral(system.Process, seal.share, 0701)
// ensure child tmpdir parent directory (e.g. `/tmp/fortify.%d/tmpdir`)
targetTmpdirParent := path.Join(seal.SharePath, "tmpdir")
seal.sys.Ensure(targetTmpdirParent, 0700)
seal.sys.UpdatePermType(system.User, targetTmpdirParent, acl.Execute)
// ensure child tmpdir (e.g. `/tmp/fortify.%d/tmpdir/%d`)
targetTmpdir := path.Join(targetTmpdirParent, seal.sys.user.Uid)
seal.sys.Ensure(targetTmpdir, 01700)
seal.sys.UpdatePermType(system.User, targetTmpdir, acl.Read, acl.Write, acl.Execute)
seal.sys.bwrap.Bind(targetTmpdir, "/tmp", false, true)
// mount tmpfs on inner shared directory (e.g. `/tmp/fortify.%d`)
seal.sys.bwrap.Tmpfs(seal.SharePath, 1*1024*1024)
}
func (seal *appSeal) sharePasswd() {
// look up shell
sh := "/bin/sh"
if s, ok := os.LookupEnv(shell); ok {
@ -44,21 +69,3 @@ func (seal *appSeal) shareSystem() {
seal.sys.bwrap.Bind(passwdPath, "/etc/passwd")
seal.sys.bwrap.Bind(groupPath, "/etc/group")
}
func (seal *appSeal) shareTmpdirChild() string {
// ensure child tmpdir parent directory (e.g. `/tmp/fortify.%d/tmpdir`)
targetTmpdirParent := path.Join(seal.SharePath, "tmpdir")
seal.sys.Ensure(targetTmpdirParent, 0700)
seal.sys.UpdatePermType(system.User, targetTmpdirParent, acl.Execute)
// ensure child tmpdir (e.g. `/tmp/fortify.%d/tmpdir/%d`)
targetTmpdir := path.Join(targetTmpdirParent, seal.sys.user.Uid)
seal.sys.Ensure(targetTmpdir, 01700)
seal.sys.UpdatePermType(system.User, targetTmpdir, acl.Read, acl.Write, acl.Execute)
seal.sys.bwrap.Bind(targetTmpdir, "/tmp", false, true)
// mount tmpfs on inner shared directory (e.g. `/tmp/fortify.%d`)
seal.sys.bwrap.Tmpfs(seal.SharePath, 1*1024*1024)
return targetTmpdir
}

6
internal/app/system.go
View File

@ -8,7 +8,6 @@ import (
"git.ophivana.moe/cat/fortify/internal"
"git.ophivana.moe/cat/fortify/internal/state"
"git.ophivana.moe/cat/fortify/internal/system"
"git.ophivana.moe/cat/fortify/internal/verbose"
)
// appSeal seals the application with child-related information
@ -76,10 +75,9 @@ func (seal *appSeal) shareAll(bus [2]*dbus.Config) error {
}
seal.shared = true
targetTmpdir := seal.shareTmpdirChild()
verbose.Printf("child tmpdir %q configured\n", targetTmpdir)
seal.shareRuntime()
seal.shareSystem()
seal.shareRuntime()
seal.sharePasswd()
if err := seal.shareDisplay(); err != nil {
return err
}