mutual authentication
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... Diffie-Hellman key exchange from Section 8 of [SSH-TRANSPORT] with
mutual authentication using GSS-API.
...
... received from S during this exchange, if any. For this call, the
client MUST set mutual_req_flag to "true" to request that mutual
authentication be performed. It also MUST set integ_req_flag to
"true" to request that per-message integrity protection ...
... GSS_S_COMPLETE and the
mutual_state flag is not true, then mutual authentication has
not been established, and the key exchange MUST fail.
...
... GSS_S_COMPLETE and the
mutual_state flag is not true, then mutual authentication has
not been established, and the key exchange MUST fail.
...
... key exchange method described in Section 2 depends on the
underlying GSS-API mechanism to provide both mutual authentication
and per-message integrity services ...