SSL_CTX_add_session, SSL_add_session, SSL_CTX_remove_session, SSL_remove_session - manipulate session cache


 #include <openssl/ssl.h>

 int SSL_CTX_add_session(SSL_CTX *ctx, SSL_SESSION *c);
 int SSL_add_session(SSL_CTX *ctx, SSL_SESSION *c);

 int SSL_CTX_remove_session(SSL_CTX *ctx, SSL_SESSION *c);
 int SSL_remove_session(SSL_CTX *ctx, SSL_SESSION *c);


SSL_CTX_add_session() adds the session c to the context ctx. The reference count for session c is incremented by 1. If a session with the same session id already exists, the old session is removed by calling SSL_SESSION_free().

SSL_CTX_remove_session() removes the session c from the context ctx. SSL_SESSION_free() is called once for c.

SSL_add_session() and SSL_remove_session() are synonyms for their SSL_CTX_*() counterparts.


When adding a new session to the internal session cache, it is examined whether a session with the same session id already exists. In this case it is assumed that both sessions are identical. If the same session is stored in a different SSL_SESSION object, The old session is removed and replaced by the new session. If the session is actually identical (the SSL_SESSION object is identical), SSL_CTX_add_session() is a no-op, and the return value is 0.

If a server SSL_CTX is configured with the SSL_SESS_CACHE_NO_INTERNAL_STORE flag then the internal cache will not be populated automatically by new sessions negotiated by the SSL/TLS implementation, even though the internal cache will be searched automatically for session-resume requests (the latter can be surpressed by SSL_SESS_CACHE_NO_INTERNAL_LOOKUP). So the application can use SSL_CTX_add_session() directly to have full control over the sessions that can be resumed if desired.


The following values are returned by all functions:


libssl, SSL_CTX_set_session_cache_mode(), SSL_SESSION_free()

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