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/**
* Hybrid Session Manager that emits both IDs and Tickets
* (C) 2023 Jack Lloyd
* 2023 René Meusel - Rohde & Schwarz Cybersecurity
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/tls_session_manager_hybrid.h>
#include <botan/assert.h>
#include <botan/rng.h>
#include <functional>
namespace Botan::TLS {
Session_Manager_Hybrid::Session_Manager_Hybrid(std::unique_ptr<Session_Manager> stateful,
const std::shared_ptr<Credentials_Manager>& credentials_manager,
const std::shared_ptr<RandomNumberGenerator>& rng,
bool prefer_tickets) :
Session_Manager(rng),
m_stateful(std::move(stateful)),
m_stateless(credentials_manager, rng),
m_prefer_tickets(prefer_tickets) {
BOTAN_ASSERT_NONNULL(m_stateful);
}
std::optional<Session_Handle> Session_Manager_Hybrid::establish(const Session& session,
const std::optional<Session_ID>& id,
bool tls12_no_ticket) {
auto create_ticket = [&]() -> std::optional<Session_Handle> {
if(tls12_no_ticket) {
return std::nullopt;
}
auto ticket_handle = m_stateless.establish(session, id, false /* always allow tickets */);
BOTAN_ASSERT_IMPLICATION(ticket_handle.has_value(),
ticket_handle->is_ticket(),
"Session_Manager_Stateless produced unexpected Session_Handle");
return ticket_handle;
};
auto create_id = [&] {
// If we're dealing with a TLS 1.2 connection, we opportunistically
// disable tickets for the underlying manager.
auto id_handle = m_stateful->establish(session, id, session.version().is_pre_tls_13());
BOTAN_ASSERT_IMPLICATION(
id_handle.has_value(), id_handle->is_id(), "Session_Manager_In_Memory produced unexpected Session_Handle");
return id_handle;
};
std::function preferred = create_ticket;
std::function fallback = create_id;
if(!m_prefer_tickets) {
std::swap(preferred, fallback);
}
if(auto result = preferred()) {
return result;
}
return fallback();
}
std::optional<Session> Session_Manager_Hybrid::retrieve(const Session_Handle& handle,
Callbacks& callbacks,
const Policy& policy) {
std::reference_wrapper<Session_Manager> preferred = m_stateless;
std::reference_wrapper<Session_Manager> fallback = *m_stateful;
if(!m_prefer_tickets) {
std::swap(preferred, fallback);
}
if(auto session = preferred.get().retrieve(handle, callbacks, policy)) {
return session;
}
return fallback.get().retrieve(handle, callbacks, policy);
}
bool Session_Manager_Hybrid::emits_session_tickets() {
return m_stateless.emits_session_tickets() || m_stateful->emits_session_tickets();
}
std::optional<Session> Session_Manager_Hybrid::retrieve_one(const Session_Handle&) {
BOTAN_ASSERT(false, "This should never be called");
}
std::vector<Session_with_Handle> Session_Manager_Hybrid::find_some(const Server_Information&, const size_t) {
BOTAN_ASSERT(false, "This should never be called");
}
} // namespace Botan::TLS