DNA barcode analysis

I have infected cells with a DNA barcoding library and Have just received the sequencing analysis.
I have a 50 bp amplicon of which the 12 last nucleotides contain a random barcode (I do not have a file with all the list of barcodes).
I am interested looking at the distribution of the barcodes including the total no. of barcodes I have and how many times each one appears.
Which tools in Galaxy can I use for that?
thank you,