docs/proxy-how-it-works.svg

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y2="292.6621"/><line style="stroke:#A80036;stroke-width:1.0;stroke-dasharray:5.0,5.0;" x1="312.5" x2="312.5" y1="40.4883" y2="292.6621"/><line style="stroke:#A80036;stroke-width:1.0;stroke-dasharray:5.0,5.0;" x1="569.5" x2="569.5" y1="40.4883" y2="292.6621"/><rect fill="#FEFECE" filter="url(#f23gs4uln4dfl)" height="30.4883" style="stroke:#A80036;stroke-width:1.5;" width="54" x="20" y="5"/><text fill="#000000" font-family="sans-serif" font-size="14" lengthAdjust="spacing" textLength="40" x="27" y="25.5352">Client</text><rect fill="#FEFECE" filter="url(#f23gs4uln4dfl)" height="30.4883" style="stroke:#A80036;stroke-width:1.5;" width="54" x="20" y="291.6621"/><text fill="#000000" font-family="sans-serif" font-size="14" lengthAdjust="spacing" textLength="40" x="27" y="312.1973">Client</text><rect fill="#FEFECE" filter="url(#f23gs4uln4dfl)" height="30.4883" style="stroke:#A80036;stroke-width:1.5;" width="53" x="284.5" y="5"/><text fill="#000000" font-family="sans-serif" font-size="14" lengthAdjust="spacing" textLength="39" x="291.5" y="25.5352">Proxy</text><rect fill="#FEFECE" filter="url(#f23gs4uln4dfl)" height="30.4883" style="stroke:#A80036;stroke-width:1.5;" width="53" x="284.5" y="291.6621"/><text fill="#000000" font-family="sans-serif" font-size="14" lengthAdjust="spacing" textLength="39" x="291.5" y="312.1973">Proxy</text><rect fill="#FEFECE" filter="url(#f23gs4uln4dfl)" height="30.4883" style="stroke:#A80036;stroke-width:1.5;" width="59" x="538.5" y="5"/><text fill="#000000" font-family="sans-serif" font-size="14" lengthAdjust="spacing" textLength="45" x="545.5" y="25.5352">Target</text><rect fill="#FEFECE" filter="url(#f23gs4uln4dfl)" height="30.4883" style="stroke:#A80036;stroke-width:1.5;" width="59" x="538.5" y="291.6621"/><text fill="#000000" font-family="sans-serif" font-size="14" lengthAdjust="spacing" textLength="45" x="545.5" y="312.1973">Target</text><polygon fill="#A80036" points="60,67.7988,50,71.7988,60,75.7988,56,71.7988" style="stroke:#A80036;stroke-width:1.0;"/><polygon fill="#A80036" points="301,67.7988,311,71.7988,301,75.7988,305,71.7988" style="stroke:#A80036;stroke-width:1.0;"/><line style="stroke:#A80036;stroke-width:1.0;" x1="54" x2="307" y1="71.7988" y2="71.7988"/><text fill="#000000" font-family="sans-serif" font-size="13" lengthAdjust="spacing" textLength="96" x="133" y="67.0566">TCP handshake</text><polygon fill="#A80036" points="301,97.1094,311,101.1094,301,105.1094,305,101.1094" style="stroke:#A80036;stroke-width:1.0;"/><line style="stroke:#A80036;stroke-width:1.0;" x1="49" x2="307" y1="101.1094" y2="101.1094"/><text fill="#000000" font-family="sans-serif" font-size="13" lengthAdjust="spacing" textLength="233" x="64.5" y="96.3672">CONNECT google.com:443 HTTP/1.1</text><polygon fill="#A80036" points="324,126.4199,314,130.4199,324,134.4199,320,130.4199" style="stroke:#A80036;stroke-width:1.0;"/><polygon fill="#A80036" points="558,126.4199,568,130.4199,558,134.4199,562,130.4199" style="stroke:#A80036;stroke-width:1.0;"/><line style="stroke:#A80036;stroke-width:1.0;" x1="318" x2="564" y1="130.4199" y2="130.4199"/><text fill="#000000" font-family="sans-serif" font-size="13" lengthAdjust="spacing" textLength="96" x="393.5" y="125.6777">TCP handshake</text><polygon fill="#A80036" points="60,155.7305,50,159.7305,60,163.7305,56,159.7305" style="stroke:#A80036;stroke-width:1.0;"/><line style="stroke:#A80036;stroke-width:1.0;" x1="54" x2="312" y1="159.7305" y2="159.7305"/><text fill="#000000" font-family="sans-serif" font-size="13" lengthAdjust="spacing" textLength="240" x="61" y="154.9883">HTTP/1.1 200 Connection established</text><path d="M10,204.041 L84,204.041 L84,211.041 L74,221.041 L10,221.041 L10,204.041 " fill="#EEEEEE" style="stroke:#000000;stroke-width:1.0;"/><rect fill="none" height="46.6211" style="stroke:#000000;stroke-width:2.0;" width="601.5" x="10" y="204.041"/><text fill="#000000" font-family="sans-serif" font-size="13" font-weight="bold" lengthAdjust="spacing" textLength="29" x="25" y="217.6094">loop</text><text fill="#000000" font-family="sans-serif" font-size="11" font-weight="bold" lengthAdjust="spacing" textLength="288" x="99" y="216.6758">[until either client or target closes TCP connection]</text><polygon fill="#A80036" points="60,238.6621,50,242.6621,60,246.6621,56,242.6621" style="stroke:#A80036;stroke-width:1.0;"/><polygon fill="#A80036" points="558,238.6621,568,242.6621,558,246.6621,562,242.6621" style="stroke:#A80036;stroke-width:1.0;"/><line style="stroke:#A80036;stroke-width:1.0;" x1="54" x2="564" y1="242.6621" y2="242.6621"/><text fill="#000000" font-family="sans-serif" font-size="13" lengthAdjust="spacing" textLength="40" x="289.5" y="237.9199">tunnel</text><!--MD5=[01311083d51fe7cee82344b72e413ed8]
@startuml

skinparam sequenceMessageAlign center

Client <-> Proxy: TCP handshake

Client -> Proxy: CONNECT google.com:443 HTTP/1.1

Proxy <-> Target: TCP handshake

Proxy -> Client: HTTP/1.1 200 Connection established
Proxy -[hidden]> Target: paaaaaaaaaaaaaaaaaaaaaaaaaaadding

loop until either client or target closes TCP connection
Client <-> Target: tunnel
end

|||
@enduml

PlantUML version 1.2021.11(Sat Oct 02 21:26:11 SGT 2021)
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Java Runtime: OpenJDK Runtime Environment
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Language: en
Country: GB
--></g></svg>