Sefer Ha’mitzvos Ha’Katzar (The concise book of mitzvos) By the Chofetz Chaim
This book lists the Torah mitzvos that can be observed today
Second Section – the Negative Commandments
136. It is a negative commandment, “a man with crushed or severed parts cannot marry a Jewish girl”
As it states in Devarim (Deuteronomy) 23:2, “a man with crushed or severed parts cannot enter the community of G-d.” If he transgresses this law and he married a Jewish woman and they have relations, they both received lashes. It is permissible for this man to marry a woman who converted to Judaism and even a Cohain who has crushed parts is allowed to marry a convert. Crushed parts and severed parts mean one of his parts was wounded or cut or crushed by a human hand. (This means it happened because of an incident and he was not born this way. If he was born that way, then it means it was done by “G-d’s hands” and he is allowed to join the community.)
This applies in all places and at all times.