This book constitutes the proceedings of the 4th International Conference on Cryptology and Information Security in Latin America, LatinCrypt 2015, held in Guadalajara, Mexico, in August 2015.The 20 papers presented were carefully reviewed and selected from 49 submissions. They were organized in topical sections named: cryptographic protocols; foundations; post-quantum cryptography; symmetric key cryptanalysis; we still love pairings; curves in cryptography; and cryptographic engineering.

Includes supplementary material: sn.pub/extras

Cryptographic Protocols.- Efficient RKA-Secure KEM and IBE Schemes Against Invertible Functions.- Simulation-Based Secure Functional Encryption in the Random Oracle Model.- The Simplest Protocol for Oblivious Transfer.- Foundations.- Depth Optimized Efficient Homomorphic Sorting.- The Chain Rule for HILL Pseudoentropy, Revisited.- Post-Quantum Cryptography.- Faster Sieving for Shortest Lattice Vectors Using Spherical Locality-Sensitive Hashing.- FHEW with Efficient Multibit Bootstrapping.- Symmetric Key Cryptanalysis.- Improved Top-Down Techniques in Differential Cryptanalysis.- Algebraic Analysis of the Simon Block Cipher Family.- Cryptanalysis of the Full 8.5-Round REESSE3+ Block Cipher.- Meet-in-the-Middle Attacks on Reduced-Round Hierocrypt-3.- State-Recovery Analysis of Spritz.- We Still Love Pairings Computing Optimal 2-3 Chains for Pairings.- Subgroup Security in Pairing-Based Cryptography.- Curves in Cryptography.- Twisted Hessian Curves.- Improved Sieving on Algebraic Curves.- Attacking a Binary GLS Elliptic Curve with Magma.- Cryptographic Engineering.- Fast Implementation of Curve25519 Using AVX2.- High-Performance Ideal Lattice-Based Cryptography on 8-Bit ATxmega Microcontrollers.- An Efficient Software Implementation of the Hash-Based Signature Scheme MSS and Its Variants.