I up-voted your parent and would down vote you if I could, here is why
(a) Defense deals are not the domain of the home minster, their oversight is the responsibility of the defense ministry.
(b) There have been 2 home minsters in the last 10 years
Shivraj Patil
P Chidambaram
Shivraj Patil and his children, Shailesh Patil and Archana Patil have faced regular accusations of corruption. The reports of their corruption are in the domain of land acquisition and obtaining permits for business that they would not otherwise have likely received. This was largely done using their fathers name and listing their home address as the home ministers residence in New Delhi. But neither of them are involved in the business of arms.
Chidambaram has 1 son Karti Chidambaram, who likewise has benefited from his fathers association. Chief among which was accusations that he received 5% stake in Aircel as kickbacks for other approvals from his father. Quote from wikipedia "according to The Pioneer and India Today reports, documents show that approval to the foreign direct investment (FDI) proposal was indeed delayed by about 7 months by P Chidambaram.". This was during the time that Chidambaram held the position of Finance minister. It would be likely that Karti benefited later from his father holding the home portfolio in the same manner as Shivraj Patil's children.
(c) From your own admission in this response, your father was to only make recommendations for purchase of equipment which is vastly different from have the authority to make purchase, which is what you claim in the first. I take it from the 2 comments that he recommended their purchase. Your comments show poor form for claiming something that is clearly not true.
(d) Last but not the least, your father spoke about matters that he had no reason to be addressing outside of his work place. The exceptions could be his role as a whistle blower which is definitely not the case here.
As someone whose father worked as director of DRDO organization and had purchasing authority for research equipment for a lab that employed 100000+ employees and 1000+ scientists, I can assure you my father never even in passing mentioned any work related information outside of work for obvious security implications.
EDIT: edited for formatting.