In is a jussive conditional particle. Nudrik is the conditional verb and naslam the apodosis; both are imperfect verbs in the jussive. A final vowel in metrical recitation does not change their underlying grammatical governance.
Al-silma is the object; wāsiʿan qualifies it. The prepositional expressions bi-māl and bi-maʿrūf identify the means used to reach peace. The resulting safety is shared security, not simply victory for one side.