I would like to check my eligibility for citizenship before I start the application.

I have a green card for six years. I was working with a US embassy abroad when I got my green card and I spent the majority of the first five years out of the States because of my work with the embassy. I used to come every year for like a month. Since September last year I have been physically present in the USA and didn't leave, but still officially employed with the embassy. Based on this information, do you think I am eligible to apply for the citizenship now? Thanks