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9697f95b8f
This reverts commit 15d999759e
.
753 lines
26 KiB
C
753 lines
26 KiB
C
/*++
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* NAME
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* tls_server 3
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* SUMMARY
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* server-side TLS engine
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* SYNOPSIS
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* #include <tls.h>
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*
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* TLS_APPL_STATE *tls_server_init(props)
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* const TLS_SERVER_INIT_PROPS *props;
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*
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* TLS_SESS_STATE *tls_server_start(props)
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* const TLS_SERVER_START_PROPS *props;
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*
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* void tls_server_stop(app_ctx, stream, failure, TLScontext)
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* TLS_APPL_STATE *app_ctx;
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* VSTREAM *stream;
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* int failure;
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* TLS_SESS_STATE *TLScontext;
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* DESCRIPTION
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* This module is the interface between Postfix TLS servers,
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* the OpenSSL library, and the TLS entropy and cache manager.
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*
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* tls_server_init() is called once when the SMTP server
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* initializes.
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* Certificate details are also decided during this phase,
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* so that peer-specific behavior is not possible.
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*
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* tls_server_start() activates the TLS feature for the VSTREAM
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* passed as argument. We assume that network buffers are flushed
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* and the TLS handshake can begin immediately.
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*
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* tls_server_stop() sends the "close notify" alert via
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* SSL_shutdown() to the peer and resets all connection specific
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* TLS data. As RFC2487 does not specify a separate shutdown, it
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* is assumed that the underlying TCP connection is shut down
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* immediately afterwards. Any further writes to the channel will
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* be discarded, and any further reads will report end-of-file.
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* If the failure flag is set, no SSL_shutdown() handshake is performed.
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*
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* Once the TLS connection is initiated, information about the TLS
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* state is available via the TLScontext structure:
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* .IP TLScontext->protocol
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* the protocol name (SSLv2, SSLv3, TLSv1),
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* .IP TLScontext->cipher_name
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* the cipher name (e.g. RC4/MD5),
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* .IP TLScontext->cipher_usebits
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* the number of bits actually used (e.g. 40),
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* .IP TLScontext->cipher_algbits
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* the number of bits the algorithm is based on (e.g. 128).
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* .PP
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* The last two values may differ from each other when export-strength
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* encryption is used.
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*
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* If the peer offered a certificate, part of the certificate data are
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* available as:
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* .IP TLScontext->peer_status
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* A bitmask field that records the status of the peer certificate
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* verification. One or more of TLS_CERT_FLAG_PRESENT and
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* TLS_CERT_FLAG_TRUSTED.
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* .IP TLScontext->peer_CN
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* Extracted CommonName of the peer, or zero-length string
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* when information could not be extracted.
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* .IP TLScontext->issuer_CN
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* Extracted CommonName of the issuer, or zero-length string
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* when information could not be extracted.
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* .IP TLScontext->peer_fingerprint
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* Fingerprint of the certificate, or zero-length string when no peer
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* certificate is available.
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* .PP
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* If no peer certificate is presented the peer_status is set to 0.
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* LICENSE
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* .ad
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* .fi
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* This software is free. You can do with it whatever you want.
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* The original author kindly requests that you acknowledge
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* the use of his software.
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* AUTHOR(S)
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* Originally written by:
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* Lutz Jaenicke
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* BTU Cottbus
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* Allgemeine Elektrotechnik
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* Universitaetsplatz 3-4
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* D-03044 Cottbus, Germany
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*
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* Updated by:
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* Wietse Venema
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* IBM T.J. Watson Research
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* P.O. Box 704
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* Yorktown Heights, NY 10598, USA
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*
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* Victor Duchovni
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* Morgan Stanley
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*--*/
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#include "StdAfx.h"
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#ifdef USE_TLS
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#ifdef ACL_UNIX
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# include <unistd.h>
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#endif
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#include <string.h>
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#include "dict.h"
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/* Global library. */
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#include "tls_params.h"
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/* TLS library. */
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#include "tls.h"
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#include "tls_mgr.h"
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#include "tls_private.h"
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#define STR(x) acl_vstring_str(x)
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#define LEN(x) ACL_VSTRING_LEN(x)
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/* Application-specific. */
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/*
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* The session_id_context indentifies the service that created a session.
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* This information is used to distinguish between multiple TLS-based
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* servers running on the same server. We use the name of the mail system.
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*/
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static const char server_session_id_context[] = "Postfix/TLS";
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#define GEN_CACHE_ID(buf, id, len, service) \
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do { \
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buf = acl_vstring_alloc(2 * (len) + 1 + strlen(service) + 3); \
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acl_hex_encode(buf, (char *) (id), (len)); \
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acl_vstring_sprintf_append(buf, "&s=%s", (service)); \
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} while (0)
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/* get_server_session_cb - callback to retrieve session from server cache */
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static SSL_SESSION *get_server_session_cb(SSL *ssl, unsigned char *session_id,
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int session_id_length, int *unused_copy acl_unused)
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{
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const char *myname = "get_server_session_cb";
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TLS_SESS_STATE *TLScontext;
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ACL_VSTRING *cache_id;
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ACL_VSTRING *session_data = acl_vstring_alloc(2048);
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SSL_SESSION *session = 0;
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if ((TLScontext = SSL_get_ex_data(ssl, TLScontext_index)) == 0)
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acl_msg_panic("%s: null TLScontext in session lookup callback", myname);
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GEN_CACHE_ID(cache_id, session_id, session_id_length, TLScontext->serverid);
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if (TLScontext->log_level >= 2)
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acl_msg_info("%s: looking up session %s in %s cache", TLScontext->namaddr,
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STR(cache_id), TLScontext->cache_type);
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/*
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* Load the session from cache and decode it.
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*/
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if (tls_mgr_lookup(TLScontext->cache_type, STR(cache_id),
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session_data) == TLS_MGR_STAT_OK) {
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session = tls_session_activate(STR(session_data), (int) LEN(session_data));
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if (session && (TLScontext->log_level >= 2))
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acl_msg_info("%s: reloaded session %s from %s cache",
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TLScontext->namaddr, STR(cache_id),
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TLScontext->cache_type);
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}
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/*
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* Clean up.
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*/
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acl_vstring_free(cache_id);
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acl_vstring_free(session_data);
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return (session);
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}
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#if 0
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/* uncache_session - remove session from internal & external cache */
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static void uncache_session(SSL_CTX *ctx, TLS_SESS_STATE *TLScontext)
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{
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ACL_VSTRING *cache_id;
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SSL_SESSION *session = SSL_get_session(TLScontext->con);
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SSL_CTX_remove_session(ctx, session);
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if (TLScontext->cache_type == 0)
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return;
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GEN_CACHE_ID(cache_id, session->session_id, session->session_id_length,
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TLScontext->serverid);
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if (TLScontext->log_level >= 2)
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acl_msg_info("%s: remove session %s from %s cache", TLScontext->namaddr,
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STR(cache_id), TLScontext->cache_type);
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tls_mgr_delete(TLScontext->cache_type, STR(cache_id));
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acl_vstring_free(cache_id);
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}
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#endif
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/* new_server_session_cb - callback to save session to server cache */
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static int new_server_session_cb(SSL *ssl, SSL_SESSION *session)
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{
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const char *myname = "new_server_session_cb";
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ACL_VSTRING *cache_id;
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TLS_SESS_STATE *TLScontext;
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ACL_VSTRING *session_data;
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if ((TLScontext = SSL_get_ex_data(ssl, TLScontext_index)) == 0)
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acl_msg_panic("%s: null TLScontext in new session callback", myname);
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GEN_CACHE_ID(cache_id, session->session_id, session->session_id_length,
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TLScontext->serverid);
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if (TLScontext->log_level >= 2)
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acl_msg_info("%s: save session %s to %s cache", TLScontext->namaddr,
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STR(cache_id), TLScontext->cache_type);
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/*
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* Passivate and save the session state.
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*/
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session_data = tls_session_passivate(session);
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if (session_data) {
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tls_mgr_update(TLScontext->cache_type, STR(cache_id),
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STR(session_data), (int) LEN(session_data));
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/*
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* Clean up.
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*/
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acl_vstring_free(session_data);
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}
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acl_vstring_free(cache_id);
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SSL_SESSION_free(session); /* 200502 */
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return (1);
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}
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/* tls_server_int - initialize the server-side TLS engine */
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void tls_server_init()
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{
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tls_params_init();
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if (!var_tlsmgr_stand_alone)
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tlsmgr_local_start(NULL);
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tls_threads_init();
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}
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/* tls_server_setup - setup the server-side TLS engine */
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int tls_server_setup(const TLS_SERVER_INIT_PROPS *props)
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{
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const char *myname = "tls_server_setup";
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const EVP_MD *md_alg;
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unsigned int md_len;
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if (props->log_level >= 2)
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acl_msg_info("initializing the server-side TLS engine");
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/*
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* Detect mismatch between compile-time headers and run-time library.
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*/
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tls_check_version();
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/*
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* Initialize the OpenSSL library by the book! To start with, we must
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* initialize the algorithms. We want cleartext error messages instead of
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* just error codes, so we load the error_strings.
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*/
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SSL_load_error_strings();
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OpenSSL_add_ssl_algorithms();
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/*
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* Create an application data index for SSL objects, so that we can
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* attach TLScontext information; this information is needed inside
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* tls_verify_certificate_callback().
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*/
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if (TLScontext_index < 0) {
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if ((TLScontext_index = SSL_get_ex_new_index(0, 0, 0, 0, 0)) < 0) {
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acl_msg_warn("%s: Cannot allocate SSL application data index: "
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"disabling TLS support", myname);
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return (-1);
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}
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}
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/*
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* If the administrator specifies an unsupported digest algorithm, fail
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* now, rather than in the middle of a TLS handshake.
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*/
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if ((md_alg = EVP_get_digestbyname(props->fpt_dgst)) == 0) {
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acl_msg_warn("%s: Digest algorithm \"%s\" not found: disabling TLS support",
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myname, props->fpt_dgst);
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return (-1);
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}
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/*
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* Sanity check: Newer shared libraries may use larger digests.
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*/
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if ((md_len = EVP_MD_size(md_alg)) > EVP_MAX_MD_SIZE) {
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acl_msg_warn("%s: Digest algorithm \"%s\" output size %u too large:"
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" disabling TLS support", myname, props->fpt_dgst, md_len);
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return (-1);
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}
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/*
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* Initialize the PRNG (Pseudo Random Number Generator) with some seed
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* from external and internal sources. Don't enable TLS without some real
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* entropy.
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*/
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if (var_tls_daemon_rand_bytes > 0 && tls_ext_seed(var_tls_daemon_rand_bytes) < 0) {
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acl_msg_warn("%s: no entropy for TLS key generation: disabling TLS support", myname);
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return (-1);
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}
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tls_int_seed();
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return (0);
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}
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TLS_APPL_STATE *tls_server_create(const TLS_SERVER_INIT_PROPS *props)
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{
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const char *myname = "tls_server_create";
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SSL_CTX *server_ctx;
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long off = 0;
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int verify_flags = SSL_VERIFY_NONE;
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int cachable;
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int protomask;
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TLS_APPL_STATE *app_ctx;
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tls_mgr_open(NULL);
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/*
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* First validate the protocols. If these are invalid, we can't continue.
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*/
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protomask = tls_protocol_mask(props->protocols);
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if (protomask == TLS_PROTOCOL_INVALID) {
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/* tls_protocol_mask() logs no warning. */
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acl_msg_warn("%s: Invalid TLS protocol list \"%s\": disabling TLS support",
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myname, props->protocols);
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return (0);
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}
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/*
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* The SSL/TLS specifications require the client to send a message in the
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* oldest specification it understands with the highest level it
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* understands in the message. Netscape communicator can still
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* communicate with SSLv2 servers, so it sends out a SSLv2 client hello.
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* To deal with it, our server must be SSLv2 aware (even if we don't like
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* SSLv2), so we need to have the SSLv23 server here. If we want to limit
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* the protocol level, we can add an option to not use SSLv2/v3/TLSv1
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* later.
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*/
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ERR_clear_error();
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if ((server_ctx = SSL_CTX_new(SSLv23_server_method())) == 0) {
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acl_msg_warn("%s: cannot allocate server SSL_CTX: disabling TLS support", myname);
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tls_print_errors();
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return (0);
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}
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/*
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* See the verify callback in tls_verify.c
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*/
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SSL_CTX_set_verify_depth(server_ctx, props->verifydepth + 1);
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/*
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* Protocol work-arounds, OpenSSL version dependent.
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*/
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off |= tls_bug_bits();
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SSL_CTX_set_options(server_ctx, off);
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/*
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* Global protocol selection.
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*/
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if (protomask != 0)
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SSL_CTX_set_options(server_ctx,
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((protomask & TLS_PROTOCOL_TLSv1) ? SSL_OP_NO_TLSv1 : 0L)
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| ((protomask & TLS_PROTOCOL_SSLv3) ? SSL_OP_NO_SSLv3 : 0L)
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| ((protomask & TLS_PROTOCOL_SSLv2) ? SSL_OP_NO_SSLv2 : 0L));
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/*
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* Set the call-back routine to debug handshake progress.
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*/
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if (props->log_level >= 2)
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SSL_CTX_set_info_callback(server_ctx, tls_info_callback);
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/*
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* Load the CA public key certificates for both the server cert and for
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* the verification of client certificates. As provided by OpenSSL we
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* support two types of CA certificate handling: One possibility is to
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* add all CA certificates to one large CAfile, the other possibility is
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* a directory pointed to by CApath, containing separate files for each
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* CA with softlinks named after the hash values of the certificate. The
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* first alternative has the advantage that the file is opened and read
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* at startup time, so that you don't have the hassle to maintain another
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* copy of the CApath directory for chroot-jail.
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*/
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if (tls_set_ca_certificate_info(server_ctx, props->CAfile, props->CApath) < 0) {
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/* tls_set_ca_certificate_info() already logs a warning. */
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SSL_CTX_free(server_ctx); /* 200411 */
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return (0);
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}
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/*
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* Load the server public key certificate and private key from file and
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* check whether the cert matches the key. We can use RSA certificates
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* ("cert") DSA certificates ("dcert") or ECDSA certificates ("eccert").
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* All three can be made available at the same time. The CA certificates
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* for all three are handled in the same setup already finished. Which
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* one is used depends on the cipher negotiated (that is: the first
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* cipher listed by the client which does match the server). A client
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* with RSA only (e.g. Netscape) will use the RSA certificate only. A
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* client with openssl-library will use RSA first if not especially
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* changed in the cipher setup.
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*/
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if (tls_set_my_certificate_key_info(server_ctx,
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props->cert_file,
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props->key_file,
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props->dcert_file,
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props->dkey_file,
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props->eccert_file,
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props->eckey_file) < 0) {
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/* tls_set_my_certificate_key_info() already logs a warning. */
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SSL_CTX_free(server_ctx); /* 200411 */
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return (0);
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}
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/*
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* According to the OpenSSL documentation, temporary RSA key is needed
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* export ciphers are in use. We have to provide one, so well, we just do
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* it.
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*/
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SSL_CTX_set_tmp_rsa_callback(server_ctx, tls_tmp_rsa_cb);
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/*
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* Diffie-Hellman key generation parameters can either be loaded from
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* files (preferred) or taken from compiled in values. First, set the
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* callback that will select the values when requested, then load the
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* (possibly) available DH parameters from files. We are generous with
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* the error handling, since we do have default values compiled in, so we
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* will not abort but just log the error message.
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*/
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SSL_CTX_set_tmp_dh_callback(server_ctx, tls_tmp_dh_cb);
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if (*props->dh1024_param_file != 0)
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tls_set_dh_from_file(props->dh1024_param_file, 1024);
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if (*props->dh512_param_file != 0)
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tls_set_dh_from_file(props->dh512_param_file, 512);
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/*
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* Enable EECDH if available, errors are not fatal, we just keep going
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* with any remaining key-exchange algorithms.
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*/
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(void) tls_set_eecdh_curve(server_ctx, props->eecdh_grade);
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/*
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* If we want to check client certificates, we have to indicate it in
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* advance. By now we only allow to decide on a global basis. If we want
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* to allow certificate based relaying, we must ask the client to provide
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* one with SSL_VERIFY_PEER. The client now can decide, whether it
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* provides one or not. We can enforce a failure of the negotiation with
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* SSL_VERIFY_FAIL_IF_NO_PEER_CERT, if we do not allow a connection
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* without one. In the "server hello" following the initialization by the
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* "client hello" the server must provide a list of CAs it is willing to
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* accept. Some clever clients will then select one from the list of
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* available certificates matching these CAs. Netscape Communicator will
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* present the list of certificates for selecting the one to be sent, or
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* it will issue a warning, if there is no certificate matching the
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* available CAs.
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*
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* With regard to the purpose of the certificate for relaying, we might like
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* a later negotiation, maybe relaying would already be allowed for other
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* reasons, but this would involve severe changes in the internal postfix
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* logic, so we have to live with it the way it is.
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*/
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if (props->ask_ccert)
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verify_flags = SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE;
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SSL_CTX_set_verify(server_ctx, verify_flags,
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tls_verify_certificate_callback);
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if (*props->CAfile)
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SSL_CTX_set_client_CA_list(server_ctx, SSL_load_client_CA_file(props->CAfile));
|
|
|
|
/*
|
|
* Initialize our own TLS server handle, before diving into the details
|
|
* of TLS session cache management.
|
|
*/
|
|
app_ctx = tls_alloc_app_context(server_ctx);
|
|
|
|
/*
|
|
* The session cache is implemented by the tlsmgr(8) server.
|
|
*
|
|
* XXX 200502 Surprise: when OpenSSL purges an entry from the in-memory
|
|
* cache, it also attempts to purge the entry from the on-disk cache.
|
|
* This is undesirable, especially when we set the in-memory cache size
|
|
* to 1. For this reason we don't allow OpenSSL to purge on-disk cache
|
|
* entries, and leave it up to the tlsmgr process instead. Found by
|
|
* Victor Duchovni.
|
|
*/
|
|
|
|
if (props->cache_type == 0 || tls_mgr_policy(props->cache_type, &cachable) != TLS_MGR_STAT_OK)
|
|
cachable = 0;
|
|
|
|
if (cachable || props->set_sessid) {
|
|
|
|
/*
|
|
* Initialize the session cache.
|
|
*
|
|
* With a large number of concurrent smtpd(8) processes, it is not a
|
|
* good idea to cache multiple large session objects in each process.
|
|
* We set the internal cache size to 1, and don't register a
|
|
* "remove_cb" so as to avoid deleting good sessions from the
|
|
* external cache prematurely (when the internal cache is full,
|
|
* OpenSSL removes sessions from the external cache also)!
|
|
*
|
|
* This makes SSL_CTX_remove_session() not useful for flushing broken
|
|
* sessions from the external cache, so we must delete them directly
|
|
* (not via a callback).
|
|
*
|
|
* Set a session id context to identify to what type of server process
|
|
* created a session. In our case, the context is simply the name of
|
|
* the mail system: "Postfix/TLS".
|
|
*/
|
|
SSL_CTX_sess_set_cache_size(server_ctx, 1);
|
|
SSL_CTX_set_session_id_context(server_ctx,
|
|
(void *) &server_session_id_context,
|
|
sizeof(server_session_id_context));
|
|
SSL_CTX_set_session_cache_mode(server_ctx,
|
|
SSL_SESS_CACHE_SERVER |
|
|
SSL_SESS_CACHE_NO_AUTO_CLEAR);
|
|
if (cachable) {
|
|
app_ctx->cache_type = acl_mystrdup(props->cache_type);
|
|
|
|
SSL_CTX_sess_set_get_cb(server_ctx, get_server_session_cb);
|
|
SSL_CTX_sess_set_new_cb(server_ctx, new_server_session_cb);
|
|
}
|
|
|
|
/*
|
|
* OpenSSL ignores timed-out sessions. We need to set the internal
|
|
* cache timeout at least as high as the external cache timeout. This
|
|
* applies even if no internal cache is used.
|
|
*/
|
|
SSL_CTX_set_timeout(server_ctx, props->scache_timeout);
|
|
} else {
|
|
|
|
/*
|
|
* If we have no external cache, disable all caching. No use wasting
|
|
* server memory resources with sessions they are unlikely to be able
|
|
* to reuse.
|
|
*/
|
|
SSL_CTX_set_session_cache_mode(server_ctx, SSL_SESS_CACHE_OFF);
|
|
}
|
|
|
|
return (app_ctx);
|
|
}
|
|
|
|
/*
|
|
* This is the actual startup routine for a new connection. We expect that
|
|
* the SMTP buffers are flushed and the "220 Ready to start TLS" was sent to
|
|
* the client, so that we can immediately start the TLS handshake process.
|
|
*/
|
|
TLS_SESS_STATE *tls_server_start(const TLS_SERVER_START_PROPS *props)
|
|
{
|
|
const char *myname = "tls_server_start";
|
|
int sts;
|
|
TLS_SESS_STATE *TLScontext;
|
|
SSL_CIPHER *cipher;
|
|
X509 *peer;
|
|
char buf[CCERT_BUFSIZ];
|
|
const char *cipher_list;
|
|
TLS_APPL_STATE *app_ctx = props->ctx;
|
|
|
|
if (props->log_level >= 1)
|
|
acl_msg_info("%s: setting up TLS connection from %s",
|
|
myname, props->namaddr);
|
|
|
|
cipher_list = tls_set_ciphers(app_ctx, "TLS", props->cipher_grade,
|
|
props->cipher_exclusions);
|
|
if (cipher_list == 0) {
|
|
acl_msg_warn("%s: %s: %s: aborting TLS session",
|
|
myname, props->namaddr, acl_vstring_str(app_ctx->why));
|
|
return (0);
|
|
}
|
|
if (props->log_level >= 2)
|
|
acl_msg_info("%s: %s: TLS cipher list \"%s\"",
|
|
myname, props->namaddr, cipher_list);
|
|
|
|
/*
|
|
* Allocate a new TLScontext for the new connection and get an SSL
|
|
* structure. Add the location of TLScontext to the SSL to later retrieve
|
|
* the information inside the tls_verify_certificate_callback().
|
|
*/
|
|
TLScontext = tls_alloc_sess_context(props->log_level, props->namaddr);
|
|
TLScontext->cache_type = app_ctx->cache_type;
|
|
|
|
TLScontext->serverid = acl_mystrdup(props->serverid);
|
|
TLScontext->am_server = 1;
|
|
|
|
ERR_clear_error();
|
|
if ((TLScontext->con = (SSL *) SSL_new(app_ctx->ssl_ctx)) == 0) {
|
|
acl_msg_warn("%s: Could not allocate 'TLScontext->con' with SSL_new()", myname);
|
|
tls_print_errors();
|
|
tls_free_context(TLScontext);
|
|
return (0);
|
|
}
|
|
if (!SSL_set_ex_data(TLScontext->con, TLScontext_index, TLScontext)) {
|
|
acl_msg_warn("%s: Could not set application data for 'TLScontext->con'", myname);
|
|
tls_print_errors();
|
|
tls_free_context(TLScontext);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* The TLS connection is realized by a BIO_pair, so obtain the pair.
|
|
*
|
|
* XXX There is no need to store the internal_bio handle in the TLScontext
|
|
* structure. It will be attached to and destroyed with TLScontext->con.
|
|
* The network_bio, however, needs to be freed explicitly, so we need to
|
|
* store its handle in TLScontext.
|
|
*/
|
|
if (!BIO_new_bio_pair(&TLScontext->internal_bio, TLS_BIO_BUFSIZE,
|
|
&TLScontext->network_bio, TLS_BIO_BUFSIZE)) {
|
|
acl_msg_warn("%s: Could not obtain BIO_pair", myname);
|
|
tls_print_errors();
|
|
tls_free_context(TLScontext);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Before really starting anything, try to seed the PRNG a little bit
|
|
* more.
|
|
*/
|
|
tls_int_seed();
|
|
if (var_tls_daemon_rand_bytes > 0)
|
|
(void) tls_ext_seed(var_tls_daemon_rand_bytes);
|
|
|
|
/*
|
|
* Initialize the SSL connection to accept state. This should not be
|
|
* necessary anymore since 0.9.3, but the call is still in the library
|
|
* and maintaining compatibility never hurts.
|
|
*/
|
|
SSL_set_accept_state(TLScontext->con);
|
|
|
|
/*
|
|
* Connect the SSL connection with the Postfix side of the BIO-pair for
|
|
* reading and writing.
|
|
*/
|
|
SSL_set_bio(TLScontext->con, TLScontext->internal_bio,
|
|
TLScontext->internal_bio);
|
|
|
|
/*
|
|
* If the debug level selected is high enough, all of the data is dumped:
|
|
* 3 will dump the SSL negotiation, 4 will dump everything.
|
|
*
|
|
* We do have an SSL_set_fd() and now suddenly a BIO_ routine is called?
|
|
* Well there is a BIO below the SSL routines that is automatically
|
|
* created for us, so we can use it for debugging purposes.
|
|
*/
|
|
if (props->log_level >= 3)
|
|
BIO_set_callback(SSL_get_rbio(TLScontext->con), tls_bio_dump_cb);
|
|
|
|
/*
|
|
* Start TLS negotiations. This process is a black box that invokes our
|
|
* call-backs for session caching and certificate verification.
|
|
*
|
|
* Error handling: If the SSL handhake fails, we print out an error message
|
|
* and remove all TLS state concerning this session.
|
|
*/
|
|
sts = tls_bio_accept(ACL_VSTREAM_SOCK(props->stream), props->timeout,
|
|
TLScontext);
|
|
if (sts <= 0) {
|
|
acl_msg_info("SSL_accept error from %s: %d", props->namaddr, sts);
|
|
tls_print_errors();
|
|
tls_free_context(TLScontext);
|
|
return (0);
|
|
}
|
|
/* Only loglevel==4 dumps everything */
|
|
if (props->log_level < 4)
|
|
BIO_set_callback(SSL_get_rbio(TLScontext->con), 0);
|
|
|
|
/*
|
|
* The caller may want to know if this session was reused or if a new
|
|
* session was negotiated.
|
|
*/
|
|
TLScontext->session_reused = SSL_session_reused(TLScontext->con);
|
|
if (TLScontext->log_level >= 2 && TLScontext->session_reused)
|
|
acl_msg_info("%s: Reusing old session", TLScontext->namaddr);
|
|
|
|
/*
|
|
* Let's see whether a peer certificate is available and what is the
|
|
* actual information. We want to save it for later use.
|
|
*/
|
|
peer = SSL_get_peer_certificate(TLScontext->con);
|
|
if (peer != NULL) {
|
|
TLScontext->peer_status |= TLS_CERT_FLAG_PRESENT;
|
|
if (SSL_get_verify_result(TLScontext->con) == X509_V_OK)
|
|
TLScontext->peer_status |= TLS_CERT_FLAG_TRUSTED;
|
|
|
|
if (props->log_level >= 2) {
|
|
X509_NAME_oneline(X509_get_subject_name(peer),
|
|
buf, sizeof(buf));
|
|
acl_msg_info("subject=%s", buf);
|
|
X509_NAME_oneline(X509_get_issuer_name(peer),
|
|
buf, sizeof(buf));
|
|
acl_msg_info("issuer=%s", buf);
|
|
}
|
|
TLScontext->peer_CN = tls_peer_CN(peer, TLScontext);
|
|
TLScontext->issuer_CN = tls_issuer_CN(peer, TLScontext);
|
|
TLScontext->peer_fingerprint = tls_fingerprint(peer, props->fpt_dgst);
|
|
|
|
if (props->log_level >= 1) {
|
|
acl_msg_info("%s: %s: subject_CN=%s, issuer=%s, fingerprint=%s",
|
|
props->namaddr,
|
|
TLS_CERT_IS_TRUSTED(TLScontext) ? "Trusted" : "Untrusted",
|
|
TLScontext->peer_CN, TLScontext->issuer_CN,
|
|
TLScontext->peer_fingerprint);
|
|
}
|
|
X509_free(peer);
|
|
} else {
|
|
TLScontext->peer_CN = acl_mystrdup("");
|
|
TLScontext->issuer_CN = acl_mystrdup("");
|
|
TLScontext->peer_fingerprint = acl_mystrdup("");
|
|
}
|
|
|
|
/*
|
|
* Finally, collect information about protocol and cipher for logging
|
|
*/
|
|
TLScontext->protocol = SSL_get_version(TLScontext->con);
|
|
cipher = SSL_get_current_cipher(TLScontext->con);
|
|
TLScontext->cipher_name = SSL_CIPHER_get_name(cipher);
|
|
TLScontext->cipher_usebits = SSL_CIPHER_get_bits(cipher,
|
|
&(TLScontext->cipher_algbits));
|
|
|
|
/*
|
|
* The TLS engine is active. Switch to the tls_timed_read/write()
|
|
* functions and make the TLScontext available to those functions.
|
|
*/
|
|
tls_stream_start(props->stream, TLScontext);
|
|
|
|
/*
|
|
* All the key facts in a single log entry.
|
|
*/
|
|
if (props->log_level >= 1)
|
|
acl_msg_info("%s TLS connection established from %s: %s with cipher %s "
|
|
"(%d/%d bits)", !TLS_CERT_IS_PRESENT(TLScontext) ? "Anonymous"
|
|
: TLS_CERT_IS_TRUSTED(TLScontext) ? "Trusted" : "Untrusted",
|
|
props->namaddr, TLScontext->protocol, TLScontext->cipher_name,
|
|
TLScontext->cipher_usebits, TLScontext->cipher_algbits);
|
|
|
|
tls_int_seed();
|
|
|
|
return (TLScontext);
|
|
}
|
|
|
|
#endif /* USE_TLS */
|