I see several different possibilites:
1. Karrar variant- It would be a simple task of turning the Karrar into a cruise missile. The only problem I have against that idea is the Karrar is a bit bulky for a Cruise missile (no pop-out wings) which makes it a little more difficult to transport. Regardless, depending on what size of warhead such a Karrar-based missile could have a good range.
2. C-802/Noor- For many years now it has been reported by various sources that the Chinese were working on a land-attack, long range variant of the C-80X family of missiles but no evidence of such a project exists. Regardless, it is certainly possible though the Noor's size makes it unlikely for a very long range system. While it is similar in length to many LR cruise missiles, it's diameter is much smaller. This option viability depends on what Iran exactly means by "Long Range".
3. Kh-55- Perhaps we will finally see an Iranian missile based on the Kh-55 illegally imported from Ukraine years ago. The only element IMO that has slowed the development of such a missile is the need to either develop or reverse-engineer a small turbofan engine needed for such a missile. If you tried using a Turbojet engine you would end up with something more like China's C-602 missile which while a good design, only has a fraction of the range the original Kh-55 does.
Now IMHO, the ranking I put this in is in terms of likeliness based on public information. A Karrar-based missile would be the simpliest to build, followed by the Noor-based missile, and finally a Kh-55 based missile being the most difficult to build. However I honestly don't know what we will see Monday.