ATTiny85 firmware with two I2C buses, a Master and a Slave

Hi, This project is for firmware on ATTiny85 that will provide two I2C buses on the same chip one Slave and one Master on different chip pins. Master I2C SDA will be PB1 pin (6) Master I2C SCL will be PB3 pin (2) Slave I2C SDA will be PB0 pin (5) Slave I2C SCL will be PB2 pin (7) The ATTiny85 will re-send all incoming I2C commands from its Slave bus to its Master bus and any responce received in its Master bus will be send back to its Slave bus. Also for a specific I2C device address it will act itself and perform actions without re-sending to the Master, it will reply only to its Slave bus. The deliverables are the complete source codes with AVR-GCC tool and compile instructions. The project is not involving any hardware deliverables, only the project source codes, so if any hardware is required for this development, since it is very common, is assumed that wil be already in the service provider's lab and included in the bids. Please bid only if you have experience in microcontrollers and ATTiny.