Actually,India doesn't need Russia or someone else to tell it that Iran is a threat.It uses much the same logic,why the US considers Saudi Arabia(an equally big sponsor of terror) as an ally.Iran is seen as a big sponsor of terrorism against the US & Israel,but not against India.OTOH,Saudi money is seen as seeping through to a number of extremists in India & the premise gets reversed.
Im not too sure whether India "likes" Iran.For one,Iran's N-programme has Pakistani help & Iran is much close economically and militarily to Beijing.& we have the fact that India is Israel's largest arms buyer.
Iran is also militarily close to Russia, and on more than nuclear technology. Russia has been selling ballistic missile equipment to Iran for some time.
I'm trying to find a map that was posted to the Free Republic site a few days ago. It showed the likely ranges (distances) of Iran's new missiles.