There are a few legislations that have a bearing on hate speech such as:

Indian Penal Code –

Sections 153A (Promoting enmity between different group on ground of religion, race, place of birth, residence, language, etc.),

153B (Imputations, assertions prejudicial to national integration),

295A (Deliberate and malicious acts, intended to outrage religious feelings),

298 (Uttering words with deliberate intent to wound the religious feelings),

505 (Statements conducing to public mischief)