Vehicular ad hoc network (VANET) has become an indispensable requirement in smart cities. The major applications are acquiring traffic information, vehicular surveillance, infotainment, etc. However, due to the use of unguided media, several security and privacy issues may arise during an ongoing communication. Attackers may conduct numerous passive/active attacks and cause threat to privacy, confidentiality, integrity and availability of the communication system, hence requiring a secure and efficient authentication system to address such vulnerabilities. Recently, various protocols have been proposed to address these challenges. Unfortunately, none could fulfill such requirements. In addition, the existing protocols are mostly based on public key cryptography. Thus, they may not be suitable for energy efficiency requirements of the evolving technologies such as LTE, LTE-Advanced, 5G and next-generation mobile networks. On the other hand, the security of the symmetric key-based protocols depends on a long-term shared secret key. This may introduce threat to forward/backward secrecy. In this paper, we propose a conditional privacy-preserving and desynchronization-resistant authentication protocol for VANET. The proposed protocol is appropriate with present and future generation mobile networks as it is based on symmetric key cryptography. The protocol employs an efficient approach to address forward/backward secrecy. In addition, our protocol does not require any re-synchronization between the communicating parties under desynchronization attack. We have verified the security properties using formal and informal analysis. Finally, a comparative performance analysis has been presented to show its efficiency.