* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2013 */
+/* Copyright (c) University of Cambridge 1995 - 2014 */
/* See the file NOTICE for conditions of use and distribution. */
/* Portions Copyright (c) The OpenSSL Project 1999 */
#include <openssl/ssl.h>
#include <openssl/err.h>
#include <openssl/rand.h>
-#ifdef EXPERIMENTAL_OCSP
-#include <openssl/ocsp.h>
+#ifndef DISABLE_OCSP
+# include <openssl/ocsp.h>
#endif
+#ifdef EXPERIMENTAL_DANE
+# include <danessl.h>
+#endif
+
-#ifdef EXPERIMENTAL_OCSP
-#define EXIM_OCSP_SKEW_SECONDS (300L)
-#define EXIM_OCSP_MAX_AGE (-1L)
+#ifndef DISABLE_OCSP
+# define EXIM_OCSP_SKEW_SECONDS (300L)
+# define EXIM_OCSP_MAX_AGE (-1L)
#endif
#if OPENSSL_VERSION_NUMBER >= 0x0090806fL && !defined(OPENSSL_NO_TLSEXT)
-#define EXIM_HAVE_OPENSSL_TLSEXT
+# define EXIM_HAVE_OPENSSL_TLSEXT
+#endif
+#if OPENSSL_VERSION_NUMBER >= 0x010100000L
+# define EXIM_HAVE_OPENSSL_CHECKHOST
+#endif
+#if OPENSSL_VERSION_NUMBER >= 0x010000000L \
+ && (OPENSSL_VERSION_NUMBER & 0x0000ff000L) >= 0x000002000L
+# define EXIM_HAVE_OPENSSL_CHECKHOST
+#endif
+
+#if !defined(EXIM_HAVE_OPENSSL_TLSEXT) && !defined(DISABLE_OCSP)
+# warning "OpenSSL library version too old; define DISABLE_OCSP in Makefile"
+# define DISABLE_OCSP
#endif
/* Structure for collecting random data for seeding. */
typedef struct tls_ext_ctx_cb {
uschar *certificate;
uschar *privatekey;
-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP
BOOL is_server;
union {
struct {
OCSP_RESPONSE *response;
} server;
struct {
- X509_STORE *verify_store;
+ X509_STORE *verify_store; /* non-null if status requested */
+ BOOL verify_required;
} client;
} u_ocsp;
#endif
uschar *server_cipher_list;
/* only passed down to tls_error: */
host_item *host;
+
+#ifdef EXPERIMENTAL_CERTNAMES
+ uschar * verify_cert_hostnames;
+#endif
+#ifdef EXPERIMENTAL_EVENT
+ uschar * event_action;
+#endif
} tls_ext_ctx_cb;
/* should figure out a cleanup of API to handle state preserved per
#ifdef EXIM_HAVE_OPENSSL_TLSEXT
static int tls_servername_cb(SSL *s, int *ad ARG_UNUSED, void *arg);
#endif
-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP
static int tls_server_stapling_cb(SSL *s, void *arg);
#endif
static int
tls_error(uschar *prefix, host_item *host, uschar *msg)
{
-if (msg == NULL)
+if (!msg)
{
ERR_error_string(ERR_get_error(), ssl_errstring);
msg = (uschar *)ssl_errstring;
}
-if (host == NULL)
+if (host)
+ {
+ log_write(0, LOG_MAIN, "H=%s [%s] TLS error on connection (%s): %s",
+ host->name, host->address, prefix, msg);
+ return FAIL;
+ }
+else
{
uschar *conn_info = smtp_get_connection_info();
if (Ustrncmp(conn_info, US"SMTP ", 5) == 0)
conn_info += 5;
+ /* I'd like to get separated H= here, but too hard for now */
log_write(0, LOG_MAIN, "TLS error on %s (%s): %s",
conn_info, prefix, msg);
return DEFER;
}
-else
- {
- log_write(0, LOG_MAIN, "TLS error on connection to %s [%s] (%s): %s",
- host->name, host->address, prefix, msg);
- return FAIL;
- }
}
/* Extreme debug
-#if defined(EXPERIMENTAL_OCSP)
+#ifndef DISABLE_OCSP
void
x509_store_dump_cert_s_names(X509_STORE * store)
{
optional verification for this case is done when requesting SSL to verify, by
setting SSL_VERIFY_FAIL_IF_NO_PEER_CERT in the non-optional case.
+May be called multiple times for different issues with a certificate, even
+for a given "depth" in the certificate chain.
+
Arguments:
state current yes/no state as 1/0
x509ctx certificate information.
*/
static int
-verify_callback(int state, X509_STORE_CTX *x509ctx, tls_support *tlsp, BOOL *calledp, BOOL *optionalp)
+verify_callback(int state, X509_STORE_CTX *x509ctx,
+ tls_support *tlsp, BOOL *calledp, BOOL *optionalp)
{
+X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx);
+int depth = X509_STORE_CTX_get_error_depth(x509ctx);
+uschar * ev;
static uschar txt[256];
-X509_NAME_oneline(X509_get_subject_name(x509ctx->current_cert),
- CS txt, sizeof(txt));
+X509_NAME_oneline(X509_get_subject_name(cert), CS txt, sizeof(txt));
if (state == 0)
{
log_write(0, LOG_MAIN, "SSL verify error: depth=%d error=%s cert=%s",
- x509ctx->error_depth,
- X509_verify_cert_error_string(x509ctx->error),
+ depth,
+ X509_verify_cert_error_string(X509_STORE_CTX_get_error(x509ctx)),
txt);
- tlsp->certificate_verified = FALSE;
*calledp = TRUE;
- if (!*optionalp) return 0; /* reject */
+ if (!*optionalp)
+ {
+ tlsp->peercert = X509_dup(cert);
+ return 0; /* reject */
+ }
DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in "
"tls_try_verify_hosts)\n");
- return 1; /* accept */
}
-if (x509ctx->error_depth != 0)
+else if (depth != 0)
{
- DEBUG(D_tls) debug_printf("SSL verify ok: depth=%d cert=%s\n",
- x509ctx->error_depth, txt);
-#ifdef EXPERIMENTAL_OCSP
+ DEBUG(D_tls) debug_printf("SSL verify ok: depth=%d SN=%s\n", depth, txt);
+#ifndef DISABLE_OCSP
if (tlsp == &tls_out && client_static_cbinfo->u_ocsp.client.verify_store)
{ /* client, wanting stapling */
/* Add the server cert's signing chain as the one
for the verification of the OCSP stapled information. */
if (!X509_STORE_add_cert(client_static_cbinfo->u_ocsp.client.verify_store,
- x509ctx->current_cert))
+ cert))
ERR_clear_error();
}
+#endif
+#ifdef EXPERIMENTAL_EVENT
+ ev = tlsp == &tls_out ? client_static_cbinfo->event_action : event_action;
+ if (ev)
+ {
+ tlsp->peercert = X509_dup(cert);
+ if (event_raise(ev, US"tls:cert", string_sprintf("%d", depth)) == DEFER)
+ {
+ log_write(0, LOG_MAIN, "SSL verify denied by event-action: "
+ "depth=%d cert=%s", depth, txt);
+ *calledp = TRUE;
+ if (!*optionalp)
+ return 0; /* reject */
+ DEBUG(D_tls) debug_printf("Event-action verify failure overridden "
+ "(host in tls_try_verify_hosts)\n");
+ }
+ X509_free(tlsp->peercert);
+ tlsp->peercert = NULL;
+ }
#endif
}
else
{
- DEBUG(D_tls) debug_printf("SSL%s peer: %s\n",
- *calledp ? "" : " authenticated", txt);
+#ifdef EXPERIMENTAL_CERTNAMES
+ uschar * verify_cert_hostnames;
+#endif
+
tlsp->peerdn = txt;
- }
+ tlsp->peercert = X509_dup(cert);
-/*XXX JGH: this looks bogus - we set "verified" first time through, which
-will be for the root CS cert (calls work down the chain). Why should it
-not be on the last call, where we're setting peerdn?
+#ifdef EXPERIMENTAL_CERTNAMES
+ if ( tlsp == &tls_out
+ && ((verify_cert_hostnames = client_static_cbinfo->verify_cert_hostnames)))
+ /* client, wanting hostname check */
-To test: set up a chain anchored by a good root-CA but with a bad server cert.
-Does certificate_verified get set?
-*/
-if (!*calledp) tlsp->certificate_verified = TRUE;
-*calledp = TRUE;
+# if EXIM_HAVE_OPENSSL_CHECKHOST
+# ifndef X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS
+# define X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS 0
+# endif
+ {
+ int sep = 0;
+ uschar * list = verify_cert_hostnames;
+ uschar * name;
+ int rc;
+ while ((name = string_nextinlist(&list, &sep, NULL, 0)))
+ if ((rc = X509_check_host(cert, name, 0,
+ X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS)))
+ {
+ if (rc < 0)
+ {
+ log_write(0, LOG_MAIN, "SSL verify error: internal error\n");
+ name = NULL;
+ }
+ break;
+ }
+ if (!name)
+ {
+ log_write(0, LOG_MAIN,
+ "SSL verify error: certificate name mismatch: \"%s\"\n", txt);
+ *calledp = TRUE;
+ if (!*optionalp)
+ return 0; /* reject */
+ DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in "
+ "tls_try_verify_hosts)\n");
+ }
+ }
+# else
+ if (!tls_is_name_for_cert(verify_cert_hostnames, cert))
+ {
+ log_write(0, LOG_MAIN,
+ "SSL verify error: certificate name mismatch: \"%s\"\n", txt);
+ *calledp = TRUE;
+ if (!*optionalp)
+ return 0; /* reject */
+ DEBUG(D_tls) debug_printf("SSL verify failure overridden (host in "
+ "tls_try_verify_hosts)\n");
+ }
+# endif
+#endif /*EXPERIMENTAL_CERTNAMES*/
+
+#ifdef EXPERIMENTAL_EVENT
+ ev = tlsp == &tls_out ? client_static_cbinfo->event_action : event_action;
+ if (ev)
+ if (event_raise(ev, US"tls:cert", US"0") == DEFER)
+ {
+ log_write(0, LOG_MAIN, "SSL verify denied by event-action: "
+ "depth=0 cert=%s", txt);
+ *calledp = TRUE;
+ if (!*optionalp)
+ return 0; /* reject */
+ DEBUG(D_tls) debug_printf("Event-action verify failure overridden "
+ "(host in tls_try_verify_hosts)\n");
+ }
+#endif
+
+ DEBUG(D_tls) debug_printf("SSL%s verify ok: depth=0 SN=%s\n",
+ *calledp ? "" : " authenticated", txt);
+ if (!*calledp) tlsp->certificate_verified = TRUE;
+ *calledp = TRUE;
+ }
-return 1; /* accept */
+return 1; /* accept, at least for this level */
}
static int
}
+#ifdef EXPERIMENTAL_DANE
+
+/* This gets called *by* the dane library verify callback, which interposes
+itself.
+*/
+static int
+verify_callback_client_dane(int state, X509_STORE_CTX * x509ctx)
+{
+X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx);
+static uschar txt[256];
+#ifdef EXPERIMENTAL_EVENT
+int depth = X509_STORE_CTX_get_error_depth(x509ctx);
+#endif
+
+X509_NAME_oneline(X509_get_subject_name(cert), CS txt, sizeof(txt));
+
+DEBUG(D_tls) debug_printf("verify_callback_client_dane: %s\n", txt);
+tls_out.peerdn = txt;
+tls_out.peercert = X509_dup(cert);
+
+#ifdef EXPERIMENTAL_EVENT
+ if (client_static_cbinfo->event_action)
+ {
+ if (event_raise(client_static_cbinfo->event_action,
+ US"tls:cert", string_sprintf("%d", depth)) == DEFER)
+ {
+ log_write(0, LOG_MAIN, "DANE verify denied by event-action: "
+ "depth=%d cert=%s", depth, txt);
+ tls_out.certificate_verified = FALSE;
+ return 0; /* reject */
+ }
+ if (depth != 0)
+ {
+ X509_free(tls_out.peercert);
+ tls_out.peercert = NULL;
+ }
+ }
+#endif
+
+if (state == 1)
+ tls_out.dane_verified =
+ tls_out.certificate_verified = TRUE;
+return 1;
+}
+
+#endif /*EXPERIMENTAL_DANE*/
+
/*************************************************
* Information callback *
if (!expand_check(dhparam, US"tls_dhparam", &dhexpanded))
return FALSE;
-if (dhexpanded == NULL || *dhexpanded == '\0')
- {
+if (!dhexpanded || !*dhexpanded)
bio = BIO_new_mem_buf(CS std_dh_prime_default(), -1);
- }
else if (dhexpanded[0] == '/')
{
- bio = BIO_new_file(CS dhexpanded, "r");
- if (bio == NULL)
+ if (!(bio = BIO_new_file(CS dhexpanded, "r")))
{
tls_error(string_sprintf("could not read dhparams file %s", dhexpanded),
host, US strerror(errno));
return TRUE;
}
- pem = std_dh_prime_named(dhexpanded);
- if (!pem)
+ if (!(pem = std_dh_prime_named(dhexpanded)))
{
tls_error(string_sprintf("Unknown standard DH prime \"%s\"", dhexpanded),
host, US strerror(errno));
bio = BIO_new_mem_buf(CS pem, -1);
}
-dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL);
-if (dh == NULL)
+if (!(dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL)))
{
BIO_free(bio);
tls_error(string_sprintf("Could not read tls_dhparams \"%s\"", dhexpanded),
-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP
/*************************************************
* Load OCSP information into state *
*************************************************/
}
supply_response:
-cbinfo->u_ocsp.server.response = resp;
+ cbinfo->u_ocsp.server.response = resp;
return;
bad:
-if (running_in_test_harness)
- {
- extern char ** environ;
- uschar ** p;
- for (p = USS environ; *p != NULL; p++)
- if (Ustrncmp(*p, "EXIM_TESTHARNESS_DISABLE_OCSPVALIDITYCHECK", 42) == 0)
- {
- DEBUG(D_tls) debug_printf("Supplying known bad OCSP response\n");
- goto supply_response;
- }
- }
+ if (running_in_test_harness)
+ {
+ extern char ** environ;
+ uschar ** p;
+ for (p = USS environ; *p != NULL; p++)
+ if (Ustrncmp(*p, "EXIM_TESTHARNESS_DISABLE_OCSPVALIDITYCHECK", 42) == 0)
+ {
+ DEBUG(D_tls) debug_printf("Supplying known bad OCSP response\n");
+ goto supply_response;
+ }
+ }
return;
}
-#endif /*EXPERIMENTAL_OCSP*/
+#endif /*!DISABLE_OCSP*/
"SSL_CTX_use_PrivateKey_file file=%s", expanded), cbinfo->host, NULL);
}
-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP
if (cbinfo->is_server && cbinfo->u_ocsp.server.file != NULL)
{
if (!expand_check(cbinfo->u_ocsp.server.file, US"tls_ocsp_file", &expanded))
not confident that memcpy wouldn't break some internal reference counting.
Especially since there's a references struct member, which would be off. */
-server_sni = SSL_CTX_new(SSLv23_server_method());
-if (!server_sni)
+if (!(server_sni = SSL_CTX_new(SSLv23_server_method())))
{
ERR_error_string(ERR_get_error(), ssl_errstring);
DEBUG(D_tls) debug_printf("SSL_CTX_new() failed: %s\n", ssl_errstring);
SSL_CTX_set_tlsext_servername_arg(server_sni, cbinfo);
if (cbinfo->server_cipher_list)
SSL_CTX_set_cipher_list(server_sni, CS cbinfo->server_cipher_list);
-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP
if (cbinfo->u_ocsp.server.file)
{
SSL_CTX_set_tlsext_status_cb(server_sni, tls_server_stapling_cb);
rc = tls_expand_session_files(server_sni, cbinfo);
if (rc != OK) return SSL_TLSEXT_ERR_NOACK;
-rc = init_dh(server_sni, cbinfo->dhparam, NULL);
-if (rc != OK) return SSL_TLSEXT_ERR_NOACK;
+if (!init_dh(server_sni, cbinfo->dhparam, NULL))
+ return SSL_TLSEXT_ERR_NOACK;
DEBUG(D_tls) debug_printf("Switching SSL context.\n");
SSL_set_SSL_CTX(s, server_sni);
-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP
/*************************************************
* Callback to handle OCSP Stapling *
uschar *response_der;
int response_der_len;
-if (log_extra_selector & LX_tls_cipher)
- log_write(0, LOG_MAIN, "[%s] Recieved OCSP stapling req;%s responding",
- sender_host_address, cbinfo->u_ocsp.server.response ? "":" not");
-else
- DEBUG(D_tls) debug_printf("Received TLS status request (OCSP stapling); %s response.",
+DEBUG(D_tls)
+ debug_printf("Received TLS status request (OCSP stapling); %s response.",
cbinfo->u_ocsp.server.response ? "have" : "lack");
+tls_in.ocsp = OCSP_NOT_RESP;
if (!cbinfo->u_ocsp.server.response)
return SSL_TLSEXT_ERR_NOACK;
response_der = NULL;
-response_der_len = i2d_OCSP_RESPONSE(cbinfo->u_ocsp.server.response, &response_der);
+response_der_len = i2d_OCSP_RESPONSE(cbinfo->u_ocsp.server.response,
+ &response_der);
if (response_der_len <= 0)
return SSL_TLSEXT_ERR_NOACK;
SSL_set_tlsext_status_ocsp_resp(server_ssl, response_der, response_der_len);
+tls_in.ocsp = OCSP_VFIED;
return SSL_TLSEXT_ERR_OK;
}
len = SSL_get_tlsext_status_ocsp_resp(s, &p);
if(!p)
{
- if (log_extra_selector & LX_tls_cipher)
- log_write(0, LOG_MAIN, "Received TLS status response, null content");
+ /* Expect this when we requested ocsp but got none */
+ if ( cbinfo->u_ocsp.client.verify_required
+ && log_extra_selector & LX_tls_cipher)
+ log_write(0, LOG_MAIN, "Received TLS status callback, null content");
else
DEBUG(D_tls) debug_printf(" null\n");
- return 0; /* This is the fail case for require-ocsp; none from server */
+ return cbinfo->u_ocsp.client.verify_required ? 0 : 1;
}
+
if(!(rsp = d2i_OCSP_RESPONSE(NULL, &p, len)))
{
+ tls_out.ocsp = OCSP_FAILED;
if (log_extra_selector & LX_tls_cipher)
- log_write(0, LOG_MAIN, "Received TLS status response, parse error");
+ log_write(0, LOG_MAIN, "Received TLS cert status response, parse error");
else
DEBUG(D_tls) debug_printf(" parse error\n");
return 0;
if(!(bs = OCSP_response_get1_basic(rsp)))
{
+ tls_out.ocsp = OCSP_FAILED;
if (log_extra_selector & LX_tls_cipher)
- log_write(0, LOG_MAIN, "Received TLS status response, error parsing response");
+ log_write(0, LOG_MAIN, "Received TLS cert status response, error parsing response");
else
DEBUG(D_tls) debug_printf(" error parsing response\n");
OCSP_RESPONSE_free(rsp);
/* We'd check the nonce here if we'd put one in the request. */
/* However that would defeat cacheability on the server so we don't. */
-
/* This section of code reworked from OpenSSL apps source;
The OpenSSL Project retains copyright:
Copyright (c) 1999 The OpenSSL Project. All rights reserved.
*/
{
BIO * bp = NULL;
- OCSP_CERTID *id;
int status, reason;
ASN1_GENERALIZEDTIME *rev, *thisupd, *nextupd;
/* Use the chain that verified the server cert to verify the stapled info */
/* DEBUG(D_tls) x509_store_dump_cert_s_names(cbinfo->u_ocsp.client.verify_store); */
- if ((i = OCSP_basic_verify(bs, NULL, cbinfo->u_ocsp.client.verify_store, 0)) <= 0)
+ if ((i = OCSP_basic_verify(bs, NULL,
+ cbinfo->u_ocsp.client.verify_store, 0)) <= 0)
{
+ tls_out.ocsp = OCSP_FAILED;
+ if (log_extra_selector & LX_tls_cipher)
+ log_write(0, LOG_MAIN, "Received TLS cert status response, itself unverifiable");
BIO_printf(bp, "OCSP response verify failure\n");
ERR_print_errors(bp);
- i = 0;
+ i = cbinfo->u_ocsp.client.verify_required ? 0 : 1;
goto out;
}
if (sk_OCSP_SINGLERESP_num(sresp) != 1)
{
- log_write(0, LOG_MAIN, "OCSP stapling with multiple responses not handled");
+ tls_out.ocsp = OCSP_FAILED;
+ log_write(0, LOG_MAIN, "OCSP stapling "
+ "with multiple responses not handled");
+ i = cbinfo->u_ocsp.client.verify_required ? 0 : 1;
goto out;
}
single = OCSP_resp_get0(bs, 0);
- status = OCSP_single_get0_status(single, &reason, &rev, &thisupd, &nextupd);
+ status = OCSP_single_get0_status(single, &reason, &rev,
+ &thisupd, &nextupd);
}
- i = 0;
DEBUG(D_tls) time_print(bp, "This OCSP Update", thisupd);
DEBUG(D_tls) if(nextupd) time_print(bp, "Next OCSP Update", nextupd);
- if (!OCSP_check_validity(thisupd, nextupd, EXIM_OCSP_SKEW_SECONDS, EXIM_OCSP_MAX_AGE))
+ if (!OCSP_check_validity(thisupd, nextupd,
+ EXIM_OCSP_SKEW_SECONDS, EXIM_OCSP_MAX_AGE))
{
+ tls_out.ocsp = OCSP_FAILED;
DEBUG(D_tls) ERR_print_errors(bp);
log_write(0, LOG_MAIN, "Server OSCP dates invalid");
- goto out;
+ i = cbinfo->u_ocsp.client.verify_required ? 0 : 1;
}
-
- DEBUG(D_tls) BIO_printf(bp, "Certificate status: %s\n", OCSP_cert_status_str(status));
- switch(status)
+ else
{
- case V_OCSP_CERTSTATUS_GOOD:
- i = 1;
- break;
- case V_OCSP_CERTSTATUS_REVOKED:
- log_write(0, LOG_MAIN, "Server certificate revoked%s%s",
- reason != -1 ? "; reason: " : "", reason != -1 ? OCSP_crl_reason_str(reason) : "");
- DEBUG(D_tls) time_print(bp, "Revocation Time", rev);
- i = 0;
- break;
- default:
- log_write(0, LOG_MAIN, "Server certificate status unknown, in OCSP stapling");
- i = 0;
- break;
+ DEBUG(D_tls) BIO_printf(bp, "Certificate status: %s\n",
+ OCSP_cert_status_str(status));
+ switch(status)
+ {
+ case V_OCSP_CERTSTATUS_GOOD:
+ tls_out.ocsp = OCSP_VFIED;
+ i = 1;
+ break;
+ case V_OCSP_CERTSTATUS_REVOKED:
+ tls_out.ocsp = OCSP_FAILED;
+ log_write(0, LOG_MAIN, "Server certificate revoked%s%s",
+ reason != -1 ? "; reason: " : "",
+ reason != -1 ? OCSP_crl_reason_str(reason) : "");
+ DEBUG(D_tls) time_print(bp, "Revocation Time", rev);
+ i = cbinfo->u_ocsp.client.verify_required ? 0 : 1;
+ break;
+ default:
+ tls_out.ocsp = OCSP_FAILED;
+ log_write(0, LOG_MAIN,
+ "Server certificate status unknown, in OCSP stapling");
+ i = cbinfo->u_ocsp.client.verify_required ? 0 : 1;
+ break;
+ }
}
out:
BIO_free(bp);
OCSP_RESPONSE_free(rsp);
return i;
}
-#endif /*EXPERIMENTAL_OCSP*/
-
+#endif /*!DISABLE_OCSP*/
/*************************************************
* Initialize for TLS *
*************************************************/
-/* Called from both server and client code, to do preliminary initialization of
-the library.
+/* Called from both server and client code, to do preliminary initialization
+of the library. We allocate and return a context structure.
Arguments:
+ ctxp returned SSL context
host connected host, if client; NULL if server
dhparam DH parameter file
certificate certificate file
privatekey private key
ocsp_file file of stapling info (server); flag for require ocsp (client)
addr address if client; NULL if server (for some randomness)
+ cbp place to put allocated callback context
Returns: OK/DEFER/FAIL
*/
static int
tls_init(SSL_CTX **ctxp, host_item *host, uschar *dhparam, uschar *certificate,
uschar *privatekey,
-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP
uschar *ocsp_file,
#endif
address_item *addr, tls_ext_ctx_cb ** cbp)
long init_options;
int rc;
BOOL okay;
-tls_ext_ctx_cb *cbinfo;
+tls_ext_ctx_cb * cbinfo;
cbinfo = store_malloc(sizeof(tls_ext_ctx_cb));
cbinfo->certificate = certificate;
cbinfo->privatekey = privatekey;
-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP
if ((cbinfo->is_server = host==NULL))
{
cbinfo->u_ocsp.server.file = ocsp_file;
cbinfo->u_ocsp.client.verify_store = NULL;
#endif
cbinfo->dhparam = dhparam;
+cbinfo->server_cipher_list = NULL;
cbinfo->host = host;
+#ifdef EXPERIMENTAL_EVENT
+cbinfo->event_action = NULL;
+#endif
SSL_load_error_strings(); /* basic set up */
OpenSSL_add_ssl_algorithms();
#ifdef EXIM_HAVE_OPENSSL_TLSEXT
if (host == NULL) /* server */
{
-# ifdef EXPERIMENTAL_OCSP
+# ifndef DISABLE_OCSP
/* We check u_ocsp.server.file, not server.response, because we care about if
the option exists, not what the current expansion might be, as SNI might
change the certificate and OCSP file in use between now and the time the
SSL_CTX_set_tlsext_servername_callback(*ctxp, tls_servername_cb);
SSL_CTX_set_tlsext_servername_arg(*ctxp, cbinfo);
}
-# ifdef EXPERIMENTAL_OCSP
+# ifndef DISABLE_OCSP
else /* client */
if(ocsp_file) /* wanting stapling */
{
# endif
#endif
+#ifdef EXPERIMENTAL_CERTNAMES
+cbinfo->verify_cert_hostnames = NULL;
+#endif
+
/* Set up the RSA callback */
SSL_CTX_set_tmp_rsa_callback(*ctxp, rsa_callback);
!SSL_CTX_load_verify_locations(sctx, CS file, CS dir))
return tls_error(US"SSL_CTX_load_verify_locations", host, NULL);
+ /* Load the list of CAs for which we will accept certs, for sending
+ to the client. This is only for the one-file tls_verify_certificates
+ variant.
+ If a list isn't loaded into the server, but
+ some verify locations are set, the server end appears to make
+ a wildcard reqest for client certs.
+ Meanwhile, the client library as deafult behaviour *ignores* the list
+ we send over the wire - see man SSL_CTX_set_client_cert_cb.
+ Because of this, and that the dir variant is likely only used for
+ the public-CA bundle (not for a private CA), not worth fixing.
+ */
if (file != NULL)
{
- SSL_CTX_set_client_CA_list(sctx, SSL_load_client_CA_file(CS file));
+ STACK_OF(X509_NAME) * names = SSL_load_client_CA_file(CS file);
+DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n",
+ sk_X509_NAME_num(names));
+ SSL_CTX_set_client_CA_list(sctx, names);
}
}
the error. */
rc = tls_init(&server_ctx, NULL, tls_dhparam, tls_certificate, tls_privatekey,
-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP
tls_ocsp_file,
#endif
NULL, &server_static_cbinfo);
optional, set up appropriately. */
tls_in.certificate_verified = FALSE;
+#ifdef EXPERIMENTAL_DANE
+tls_in.dane_verified = FALSE;
+#endif
server_verify_callback_called = FALSE;
if (verify_check_host(&tls_verify_hosts) == OK)
debug_printf("Shared ciphers: %s\n", buf);
}
+/* Record the certificate we presented */
+ {
+ X509 * crt = SSL_get_certificate(server_ssl);
+ tls_in.ourcert = crt ? X509_dup(crt) : NULL;
+ }
/* Only used by the server-side tls (tls_in), including tls_getc.
Client-side (tls_out) reads (seem to?) go via
+static int
+tls_client_basic_ctx_init(SSL_CTX * ctx,
+ host_item * host, smtp_transport_options_block * ob
+#ifdef EXPERIMENTAL_CERTNAMES
+ , tls_ext_ctx_cb * cbinfo
+#endif
+ )
+{
+int rc;
+/* stick to the old behaviour for compatibility if tls_verify_certificates is
+ set but both tls_verify_hosts and tls_try_verify_hosts is not set. Check only
+ the specified host patterns if one of them is defined */
+
+if ((!ob->tls_verify_hosts && !ob->tls_try_verify_hosts) ||
+ (verify_check_host(&ob->tls_verify_hosts) == OK))
+ {
+ if ((rc = setup_certs(ctx, ob->tls_verify_certificates,
+ ob->tls_crl, host, FALSE, verify_callback_client)) != OK)
+ return rc;
+ client_verify_optional = FALSE;
+
+#ifdef EXPERIMENTAL_CERTNAMES
+ if (ob->tls_verify_cert_hostnames)
+ {
+ if (!expand_check(ob->tls_verify_cert_hostnames,
+ US"tls_verify_cert_hostnames",
+ &cbinfo->verify_cert_hostnames))
+ return FAIL;
+ if (cbinfo->verify_cert_hostnames)
+ DEBUG(D_tls) debug_printf("Cert hostname to check: \"%s\"\n",
+ cbinfo->verify_cert_hostnames);
+ }
+#endif
+ }
+else if (verify_check_host(&ob->tls_try_verify_hosts) == OK)
+ {
+ if ((rc = setup_certs(ctx, ob->tls_verify_certificates,
+ ob->tls_crl, host, TRUE, verify_callback_client)) != OK)
+ return rc;
+ client_verify_optional = TRUE;
+ }
+
+return OK;
+}
+
+
+#ifdef EXPERIMENTAL_DANE
+static int
+dane_tlsa_load(SSL * ssl, host_item * host, dns_answer * dnsa)
+{
+dns_record * rr;
+dns_scan dnss;
+const char * hostnames[2] = { CS host->name, NULL };
+int found = 0;
+
+if (DANESSL_init(ssl, NULL, hostnames) != 1)
+ return tls_error(US"hostnames load", host, NULL);
+
+for (rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS);
+ rr;
+ rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)
+ ) if (rr->type == T_TLSA)
+ {
+ uschar * p = rr->data;
+ uint8_t usage, selector, mtype;
+ const char * mdname;
+
+ usage = *p++;
+
+ /* Only DANE-TA(2) and DANE-EE(3) are supported */
+ if (usage != 2 && usage != 3) continue;
+
+ selector = *p++;
+ mtype = *p++;
+
+ switch (mtype)
+ {
+ default: continue; /* Only match-types 0, 1, 2 are supported */
+ case 0: mdname = NULL; break;
+ case 1: mdname = "sha256"; break;
+ case 2: mdname = "sha512"; break;
+ }
+
+ found++;
+ switch (DANESSL_add_tlsa(ssl, usage, selector, mdname, p, rr->size - 3))
+ {
+ default:
+ case 0: /* action not taken */
+ return tls_error(US"tlsa load", host, NULL);
+ case 1: break;
+ }
+
+ tls_out.tlsa_usage |= 1<<usage;
+ }
+
+if (found)
+ return OK;
+
+log_write(0, LOG_MAIN, "DANE error: No usable TLSA records");
+return FAIL;
+}
+#endif /*EXPERIMENTAL_DANE*/
+
+
/*************************************************
* Start a TLS session in a client *
fd the fd of the connection
host connected host (for messages)
addr the first address
- certificate certificate file
- privatekey private key file
- sni TLS SNI to send to remote host
- verify_certs file for certificate verify
- crl file containing CRL
- require_ciphers list of allowed ciphers
- dh_min_bits minimum number of bits acceptable in server's DH prime
- (unused in OpenSSL)
- timeout startup timeout
- verify_hosts mandatory client verification
- try_verify_hosts optional client verification
+ tb transport (always smtp)
+ tlsa_dnsa tlsa lookup, if DANE, else null
Returns: OK on success
FAIL otherwise - note that tls_error() will not give DEFER
int
tls_client_start(int fd, host_item *host, address_item *addr,
- uschar *certificate, uschar *privatekey, uschar *sni,
- uschar *verify_certs, uschar *crl,
- uschar *require_ciphers,
-#ifdef EXPERIMENTAL_OCSP
- uschar *hosts_require_ocsp,
-#endif
- int dh_min_bits ARG_UNUSED, int timeout,
- uschar *verify_hosts, uschar *try_verify_hosts)
+ transport_instance *tb
+#ifdef EXPERIMENTAL_DANE
+ , dns_answer * tlsa_dnsa
+#endif
+ )
{
+smtp_transport_options_block * ob =
+ (smtp_transport_options_block *)tb->options_block;
static uschar txt[256];
-uschar *expciphers;
-X509* server_cert;
+uschar * expciphers;
+X509 * server_cert;
int rc;
static uschar cipherbuf[256];
-#ifdef EXPERIMENTAL_OCSP
-BOOL require_ocsp = verify_check_this_host(&hosts_require_ocsp,
- NULL, host->name, host->address, NULL) == OK;
+
+#ifndef DISABLE_OCSP
+BOOL request_ocsp = FALSE;
+BOOL require_ocsp = FALSE;
+#endif
+
+#ifdef EXPERIMENTAL_DANE
+tls_out.tlsa_usage = 0;
#endif
-rc = tls_init(&client_ctx, host, NULL, certificate, privatekey,
-#ifdef EXPERIMENTAL_OCSP
- require_ocsp ? US"" : NULL,
+#ifndef DISABLE_OCSP
+ {
+# ifdef EXPERIMENTAL_DANE
+ if ( tlsa_dnsa
+ && ob->hosts_request_ocsp[0] == '*'
+ && ob->hosts_request_ocsp[1] == '\0'
+ )
+ {
+ /* Unchanged from default. Use a safer one under DANE */
+ request_ocsp = TRUE;
+ ob->hosts_request_ocsp = US"${if or { {= {0}{$tls_out_tlsa_usage}} "
+ " {= {4}{$tls_out_tlsa_usage}} } "
+ " {*}{}}";
+ }
+# endif
+
+ if ((require_ocsp = verify_check_this_host(&ob->hosts_require_ocsp,
+ NULL, host->name, host->address, NULL) == OK))
+ request_ocsp = TRUE;
+ else
+# ifdef EXPERIMENTAL_DANE
+ if (!request_ocsp)
+# endif
+ request_ocsp = verify_check_this_host(&ob->hosts_request_ocsp,
+ NULL, host->name, host->address, NULL) == OK;
+ }
+#endif
+
+rc = tls_init(&client_ctx, host, NULL,
+ ob->tls_certificate, ob->tls_privatekey,
+#ifndef DISABLE_OCSP
+ (void *)(long)request_ocsp,
#endif
addr, &client_static_cbinfo);
if (rc != OK) return rc;
tls_out.certificate_verified = FALSE;
client_verify_callback_called = FALSE;
-if (!expand_check(require_ciphers, US"tls_require_ciphers", &expciphers))
+if (!expand_check(ob->tls_require_ciphers, US"tls_require_ciphers",
+ &expciphers))
return FAIL;
/* In OpenSSL, cipher components are separated by hyphens. In GnuTLS, they
return tls_error(US"SSL_CTX_set_cipher_list", host, NULL);
}
-/* stick to the old behaviour for compatibility if tls_verify_certificates is
- set but both tls_verify_hosts and tls_try_verify_hosts is not set. Check only
- the specified host patterns if one of them is defined */
-if (((verify_hosts == NULL) && (try_verify_hosts == NULL)) ||
- (verify_check_host(&verify_hosts) == OK))
+#ifdef EXPERIMENTAL_DANE
+if (tlsa_dnsa)
{
- rc = setup_certs(client_ctx, verify_certs, crl, host, FALSE, verify_callback_client);
- if (rc != OK) return rc;
- client_verify_optional = FALSE;
- }
-else if (verify_check_host(&try_verify_hosts) == OK)
- {
- rc = setup_certs(client_ctx, verify_certs, crl, host, TRUE, verify_callback_client);
- if (rc != OK) return rc;
- client_verify_optional = TRUE;
+ SSL_CTX_set_verify(client_ctx, SSL_VERIFY_PEER, verify_callback_client_dane);
+
+ if (!DANESSL_library_init())
+ return tls_error(US"library init", host, NULL);
+ if (DANESSL_CTX_init(client_ctx) <= 0)
+ return tls_error(US"context init", host, NULL);
}
+else
+
+#endif
+
+ if ((rc = tls_client_basic_ctx_init(client_ctx, host, ob
+#ifdef EXPERIMENTAL_CERTNAMES
+ , client_static_cbinfo
+#endif
+ )) != OK)
+ return rc;
-if ((client_ssl = SSL_new(client_ctx)) == NULL) return tls_error(US"SSL_new", host, NULL);
+if ((client_ssl = SSL_new(client_ctx)) == NULL)
+ return tls_error(US"SSL_new", host, NULL);
SSL_set_session_id_context(client_ssl, sid_ctx, Ustrlen(sid_ctx));
SSL_set_fd(client_ssl, fd);
SSL_set_connect_state(client_ssl);
-if (sni)
+if (ob->tls_sni)
{
- if (!expand_check(sni, US"tls_sni", &tls_out.sni))
+ if (!expand_check(ob->tls_sni, US"tls_sni", &tls_out.sni))
return FAIL;
if (tls_out.sni == NULL)
{
}
}
-#ifdef EXPERIMENTAL_OCSP
+#ifdef EXPERIMENTAL_DANE
+if (tlsa_dnsa)
+ if ((rc = dane_tlsa_load(client_ssl, host, tlsa_dnsa)) != OK)
+ return rc;
+#endif
+
+#ifndef DISABLE_OCSP
/* Request certificate status at connection-time. If the server
does OCSP stapling we will get the callback (set in tls_init()) */
-if (require_ocsp)
+# ifdef EXPERIMENTAL_DANE
+if (request_ocsp)
+ {
+ const uschar * s;
+ if ( ((s = ob->hosts_require_ocsp) && Ustrstr(s, US"tls_out_tlsa_usage"))
+ || ((s = ob->hosts_request_ocsp) && Ustrstr(s, US"tls_out_tlsa_usage"))
+ )
+ { /* Re-eval now $tls_out_tlsa_usage is populated. If
+ this means we avoid the OCSP request, we wasted the setup
+ cost in tls_init(). */
+ require_ocsp = verify_check_this_host(&ob->hosts_require_ocsp,
+ NULL, host->name, host->address, NULL) == OK;
+ request_ocsp = require_ocsp ? TRUE
+ : verify_check_this_host(&ob->hosts_request_ocsp,
+ NULL, host->name, host->address, NULL) == OK;
+ }
+ }
+# endif
+
+if (request_ocsp)
+ {
SSL_set_tlsext_status_type(client_ssl, TLSEXT_STATUSTYPE_ocsp);
+ client_static_cbinfo->u_ocsp.client.verify_required = require_ocsp;
+ tls_out.ocsp = OCSP_NOT_RESP;
+ }
+#endif
+
+#ifdef EXPERIMENTAL_EVENT
+client_static_cbinfo->event_action = tb->event_action;
#endif
/* There doesn't seem to be a built-in timeout on connection. */
DEBUG(D_tls) debug_printf("Calling SSL_connect\n");
sigalrm_seen = FALSE;
-alarm(timeout);
+alarm(ob->command_timeout);
rc = SSL_connect(client_ssl);
alarm(0);
+#ifdef EXPERIMENTAL_DANE
+if (tlsa_dnsa)
+ DANESSL_cleanup(client_ssl);
+#endif
+
if (rc <= 0)
return tls_error(US"SSL_connect", host, sigalrm_seen ? US"timed out" : NULL);
DEBUG(D_tls) debug_printf("SSL_connect succeeded\n");
/* Beware anonymous ciphers which lead to server_cert being NULL */
+/*XXX server_cert is never freed... use X509_free() */
server_cert = SSL_get_peer_certificate (client_ssl);
if (server_cert)
{
tls_out.peerdn = US X509_NAME_oneline(X509_get_subject_name(server_cert),
CS txt, sizeof(txt));
- tls_out.peerdn = txt;
+ tls_out.peerdn = txt; /*XXX a static buffer... */
}
else
tls_out.peerdn = NULL;
construct_cipher_name(client_ssl, cipherbuf, sizeof(cipherbuf), &tls_out.bits);
tls_out.cipher = cipherbuf;
+/* Record the certificate we presented */
+ {
+ X509 * crt = SSL_get_certificate(client_ssl);
+ tls_out.ourcert = crt ? X509_dup(crt) : NULL;
+ }
+
tls_out.active = fd;
return OK;
}
return TRUE;
}
+/* vi: aw ai sw=2
+*/
/* End of tls-openssl.c */
projects / exim.git / blobdiff