[BUG] Multiple symlinks cannot be made to point to the same destination

[pmengelbert]

Expected Behavior

You should be able to create multiple symlinks that point to the same location. For example:

image:
  post:
    symlinks:
      - oldpath: /bin/busybox
        newpath: /usr/bin/sh
      - oldpath: /bin/busybox
         newpath: /usr/bin/test

Actual Behavior

The spec format requires:

image:
  post:
    symlinks:
      /bin/busybox:
        path: /usr/bin/sh
      /bin/busybox:
         path: /usr/bin/test

This causes a yaml parsing error at best, and silently overwrites the /bin/busybox map key at worst.

Steps To Reproduce

n/a, see above.

Are you willing to submit PRs to contribute to this bug fix?

• Yes, I am willing to implement it.

[cpuguy83]

Note, we already have a type for this in the artifact section: https://github.com/Azure/dalec/blob/08d2e6c5336862ce4cadf4e32c346ca04f40d4db/artifacts.go#L49-L57

The case for symlinks in the image-post is a slightly different one though (really a hack so we don't need to create multiple packages).

[cpuguy83]

I think we could change https://github.com/Azure/dalec/blob/08d2e6c5336862ce4cadf4e32c346ca04f40d4db/spec.go#L131-L134 to include a paths field that would be muttually exclusive with path (so specify one or the other, not both) which is a []string

[pmengelbert]

Note, we already have a type for this in the artifact section:

dalec/artifacts.go

Lines 49 to 57 in 08d2e6c

type ArtifactSymlinkConfig struct {
// Source is the path that is being linked to
// Example:
// If you want a symlink in /usr/bin/foo that is linking to /usr/bin/foo/foo
// then the Source is /usr/bin/foo/foo
Source string yaml:"source,omitempty" json:"source,omitempty"
// Dest is the path where the symlink will be installed
Dest string yaml:"dest,omitempty" json:"dest,omitempty"
}
The case for symlinks in the image-post is a slightly different one though (really a hack so we don't need to create multiple packages).

Can these symlinks be placed in arbitrary locations? Or are they intended for linking stuff nested under, for example, /usr/bin?

[pmengelbert]

I think we could change

dalec/spec.go

Lines 131 to 134 in 08d2e6c

type SymlinkTarget struct {
// Path is the path where the symlink should be placed
Path string yaml:"path" json:"path" jsonschema:"required"
}
to include a paths field that would be muttually exclusive with path (so specify one or the other, not both) which is a []string

Sounds like a good approach. I will implement this prior to #494.

[pmengelbert]

Fixed by #495