Opportunistic networks (OppNets) are a type of wireless network where the nodes communicate opportunistically without a dedicated link between the source and destination. As there is no end-to-end connectivity in OppNets, nodes rely on their neighboring nodes for packet forwarding. However, if these nodes are uncooperative or malicious, the network performance can be significantly impacted. This lack of cooperation may be due to resource constraints or malicious intent. Taking these issues into consideration, this paper proposes a History-based Secure Routing Protocol against DoS Attacks in Opportunistic Networks (denoted HSRP). HSRP first identifies the neighboring nodes of any given node, and forwards the packets only to those nodes moving toward the destination, based on their residual energy levels and transmitting index. Through simulations using the ONE simulator, HSRP is shown to outperform the Disjoint multipath based secure routing in opportunistic networks (D-MUST), and the History-based secure routing protocol to detect blackhole and greyhole attacks in Opportunistic networks (SHBPR) protocols in terms of delivery probability and number of messages dropped, under varying buffer size, and time-to-live (TTL).