The invention discloses a Hash calculation method and a 
signcryption method based on a homomorphic chameleon 
Hash function. According to the provided homomorphic chameleon 
hash function, a chameleon hash value result adopts a logarithm form, a 
signcryption result based on the hash in the 
signcryption method is also a logarithm form, so that the homomorphic property is achieved, the homomorphic aggregation can be conducted in hash calculation, hash is more efficiently calculated, and the homomorphic chameleon 
hash function has both the homomorphic state and the 
key leakage prevention characteristics. The signcryption method is realized on the basis of the homomorphic chameleon 
hash function, the homomorphic aggregation signcryption ensures the homomorphism, the 
system public parameters generated by the 
system initialization are used together by the chameleon hash function and the signcryption, and two 
password schemes share one set of 
system parameters, so that 
multiple function effectscan be realized under one set of shared 
system parameters, and multiple functions are supported under the same framework. Secondly, the proxy 
key generation and proxy re-signature steps realize the proxy re-signature, and the non-repudiation is realized through a repudiation step.