@startuml
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participant Client
participant Server

Client -> Server : R, enc(H(DSAPub), R, El(CDHPub))
note right
R=rand(64bit)
CDHPriv=rand(256bit)
end note

Server -> Client : enc(H(DSAPub), R+1, El(SDHPub))\nenc(K, R, RS+SS)
note right
SDHPriv=rand(256bit)
K=H(DH(SDHPriv, CDHPub))
RS=rand(64bit)
SS=rand(256bit)
end note

Client -> Server : enc(K, R+1, RS+RC+SC+Sign(DSAPriv, K))
note right
K=H(DH(CDHPriv, SDHPub))
RC=rand(64bit)
SC=rand(256bit)
end note

Server -> Client : enc(K, R+2, RC)
note right
compare(RS)
compare(RC)
Verify(DSAPub, Sign(DSAPriv, K), K)
MasterKey=SS XOR SC
end note

@enduml