Share the TLS session cache across requests - #105
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Add CURL_LOCK_DATA_SSL_SESSION to the curl share, so a new connection to an https origin resumes a TLS session instead of a full handshake. Every fetch still opens its own socket, so the address guard runs on each.
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What
Add
CURL_LOCK_DATA_SSL_SESSIONto the curl share, alongside the DNS cache it already shares. A new connection to anhttpsorigin can resume a TLS session instead of running a full handshake.Why
This is the safe part of the connection-reuse work. Full keep-alive connection reuse is not included: a reused connection skips curl's open-socket callback, which is where the network guard checks the resolved address, so reuse would let a connection opened under one configuration serve a later request whose configuration refuses that address — an SSRF-guard bypass. Testing confirmed
CURLOPT_PREREQFUNCTIONdid not reliably re-check reused connections here, so connection reuse is left for a separate, security-reviewed change. Sharing only the session cache keeps every fetch opening its own socket, so the guard runs on each.Verify
Run
make -C test test; all 267 cases pass. The fixture origin ishttp, so the session cache has no effect on the golden output; the benefit is onhttpsorigins in production.