* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2015 */
+/* Copyright (c) University of Cambridge 1995 - 2017 */
/* See the file NOTICE for conditions of use and distribution. */
/* Portions Copyright (c) The OpenSSL Project 1999 */
#if OPENSSL_VERSION_NUMBER >= 0x0090806fL && !defined(OPENSSL_NO_TLSEXT)
# define EXIM_HAVE_OPENSSL_TLSEXT
#endif
+#if OPENSSL_VERSION_NUMBER >= 0x00908000L
+# define EXIM_HAVE_RSA_GENKEY_EX
+#endif
+#if OPENSSL_VERSION_NUMBER >= 0x10100000L
+# define EXIM_HAVE_OCSP_RESP_COUNT
+# define EXIM_HAVE_OPENSSL_DH_BITS
+#else
+# define EXIM_HAVE_EPHEM_RSA_KEX
+# define EXIM_HAVE_RAND_PSEUDO
+#endif
+#if (OPENSSL_VERSION_NUMBER >= 0x0090800fL) && !defined(OPENSSL_NO_SHA256)
+# define EXIM_HAVE_SHA256
+#endif
/*
* X509_check_host provides sane certificate hostname checking, but was added
&& (OPENSSL_VERSION_NUMBER & 0x0000ff000L) >= 0x000002000L
# define EXIM_HAVE_OPENSSL_CHECKHOST
# endif
+#endif
+#if !defined(LIBRESSL_VERSION_NUMBER) \
+ || LIBRESSL_VERSION_NUMBER >= 0x20010000L
# if !defined(OPENSSL_NO_ECDH)
# if OPENSSL_VERSION_NUMBER >= 0x0090800fL
# define EXIM_HAVE_ECDH
# endif
# if OPENSSL_VERSION_NUMBER >= 0x10002000L
-# define EXIM_HAVE_OPENSSL_ECDH_AUTO
# define EXIM_HAVE_OPENSSL_EC_NIST2NID
# endif
# endif
uschar *privatekey;
#ifndef DISABLE_OCSP
BOOL is_server;
+ STACK_OF(X509) *verify_stack; /* chain for verifying the proof */
union {
struct {
uschar *file;
/* only passed down to tls_error: */
host_item *host;
const uschar * verify_cert_hostnames;
-#ifdef EXPERIMENTAL_EVENT
+#ifndef DISABLE_EVENT
uschar * event_action;
#endif
} tls_ext_ctx_cb;
static int
setup_certs(SSL_CTX *sctx, uschar *certs, uschar *crl, host_item *host, BOOL optional,
- int (*cert_vfy_cb)(int, X509_STORE_CTX *) );
+ int (*cert_vfy_cb)(int, X509_STORE_CTX *), uschar ** errstr );
/* Callbacks */
#ifdef EXIM_HAVE_OPENSSL_TLSEXT
host NULL if setting up a server;
the connected host if setting up a client
msg error message or NULL if we should ask OpenSSL
+ errstr pointer to output error message
Returns: OK/DEFER/FAIL
*/
static int
-tls_error(uschar * prefix, const host_item * host, uschar * msg)
+tls_error(uschar * prefix, const host_item * host, uschar * msg, uschar ** errstr)
{
if (!msg)
{
ERR_error_string(ERR_get_error(), ssl_errstring);
- msg = (uschar *)ssl_errstring;
+ msg = US ssl_errstring;
}
-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;
- }
+if (errstr) *errstr = string_sprintf("(%s): %s", prefix, msg);
+return host ? FAIL : DEFER;
}
+#ifdef EXIM_HAVE_EPHEM_RSA_KEX
/*************************************************
* Callback to generate RSA key *
*************************************************/
rsa_callback(SSL *s, int export, int keylength)
{
RSA *rsa_key;
+#ifdef EXIM_HAVE_RSA_GENKEY_EX
+BIGNUM *bn = BN_new();
+#endif
+
export = export; /* Shut picky compilers up */
DEBUG(D_tls) debug_printf("Generating %d bit RSA key...\n", keylength);
-rsa_key = RSA_generate_key(keylength, RSA_F4, NULL, NULL);
-if (rsa_key == NULL)
+
+#ifdef EXIM_HAVE_RSA_GENKEY_EX
+if ( !BN_set_word(bn, (unsigned long)RSA_F4)
+ || !(rsa_key = RSA_new())
+ || !RSA_generate_key_ex(rsa_key, keylength, bn, NULL)
+ )
+#else
+if (!(rsa_key = RSA_generate_key(keylength, RSA_F4, NULL, NULL)))
+#endif
+
{
ERR_error_string(ERR_get_error(), ssl_errstring);
log_write(0, LOG_MAIN|LOG_PANIC, "TLS error (RSA_generate_key): %s",
}
return rsa_key;
}
+#endif
*/
-#ifdef EXPERIMENTAL_EVENT
+#ifndef DISABLE_EVENT
static int
verify_event(tls_support * tlsp, X509 * cert, int depth, const uschar * dn,
BOOL *calledp, const BOOL *optionalp, const uschar * what)
ev = tlsp == &tls_out ? client_static_cbinfo->event_action : event_action;
if (ev)
{
+ DEBUG(D_tls) debug_printf("verify_event: %s %d\n", what, depth);
old_cert = tlsp->peercert;
tlsp->peercert = X509_dup(cert);
/* NB we do not bother setting peerdn */
for a given "depth" in the certificate chain.
Arguments:
- state current yes/no state as 1/0
- x509ctx certificate information.
- client TRUE for client startup, FALSE for server startup
+ preverify_ok current yes/no state as 1/0
+ x509ctx certificate information.
+ tlsp per-direction (client vs. server) support data
+ calledp has-been-called flag
+ optionalp verification-is-optional flag
-Returns: 1 if verified, 0 if not
+Returns: 0 if verification should fail, otherwise 1
*/
static int
-verify_callback(int state, X509_STORE_CTX *x509ctx,
+verify_callback(int preverify_ok, X509_STORE_CTX *x509ctx,
tls_support *tlsp, BOOL *calledp, BOOL *optionalp)
{
X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx);
X509_NAME_oneline(X509_get_subject_name(cert), CS dn, sizeof(dn));
dn[sizeof(dn)-1] = '\0';
-if (state == 0)
+if (preverify_ok == 0)
{
- log_write(0, LOG_MAIN, "[%s] SSL verify error: depth=%d error=%s cert=%s",
- tlsp == &tls_out ? deliver_host_address : sender_host_address,
- depth,
- X509_verify_cert_error_string(X509_STORE_CTX_get_error(x509ctx)),
- dn);
+ uschar * extra = verify_mode ? string_sprintf(" (during %c-verify for [%s])",
+ *verify_mode, sender_host_address)
+ : US"";
+ log_write(0, LOG_MAIN, "[%s] SSL verify error%s: depth=%d error=%s cert=%s",
+ tlsp == &tls_out ? deliver_host_address : sender_host_address,
+ extra, depth,
+ X509_verify_cert_error_string(X509_STORE_CTX_get_error(x509ctx)), dn);
*calledp = TRUE;
if (!*optionalp)
{
if (!X509_STORE_add_cert(client_static_cbinfo->u_ocsp.client.verify_store,
cert))
ERR_clear_error();
+ sk_X509_push(client_static_cbinfo->verify_stack, cert);
}
#endif
-#ifdef EXPERIMENTAL_EVENT
+#ifndef DISABLE_EVENT
if (verify_event(tlsp, cert, depth, dn, calledp, optionalp, US"SSL"))
return 0; /* reject, with peercert set */
#endif
uschar * name;
int rc;
while ((name = string_nextinlist(&list, &sep, NULL, 0)))
- if ((rc = X509_check_host(cert, name, 0,
+ if ((rc = X509_check_host(cert, CCS name, 0,
X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS
| X509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS,
NULL)))
if (rc < 0)
{
log_write(0, LOG_MAIN, "[%s] SSL verify error: internal error",
- tlsp == &tls_out ? deliver_host_address : sender_host_address);
+ tlsp == &tls_out ? deliver_host_address : sender_host_address);
name = NULL;
}
break;
if (!tls_is_name_for_cert(verify_cert_hostnames, cert))
#endif
{
+ uschar * extra = verify_mode
+ ? string_sprintf(" (during %c-verify for [%s])",
+ *verify_mode, sender_host_address)
+ : US"";
log_write(0, LOG_MAIN,
- "[%s] SSL verify error: certificate name mismatch: \"%s\"",
- tlsp == &tls_out ? deliver_host_address : sender_host_address,
- dn);
+ "[%s] SSL verify error%s: certificate name mismatch: DN=\"%s\" H=\"%s\"",
+ tlsp == &tls_out ? deliver_host_address : sender_host_address,
+ extra, dn, verify_cert_hostnames);
*calledp = TRUE;
if (!*optionalp)
{
}
}
-#ifdef EXPERIMENTAL_EVENT
+#ifndef DISABLE_EVENT
if (verify_event(tlsp, cert, depth, dn, calledp, optionalp, US"SSL"))
return 0; /* reject, with peercert set */
#endif
}
static int
-verify_callback_client(int state, X509_STORE_CTX *x509ctx)
+verify_callback_client(int preverify_ok, X509_STORE_CTX *x509ctx)
{
-return verify_callback(state, x509ctx, &tls_out, &client_verify_callback_called, &client_verify_optional);
+return verify_callback(preverify_ok, x509ctx, &tls_out,
+ &client_verify_callback_called, &client_verify_optional);
}
static int
-verify_callback_server(int state, X509_STORE_CTX *x509ctx)
+verify_callback_server(int preverify_ok, X509_STORE_CTX *x509ctx)
{
-return verify_callback(state, x509ctx, &tls_in, &server_verify_callback_called, &server_verify_optional);
+return verify_callback(preverify_ok, x509ctx, &tls_in,
+ &server_verify_callback_called, &server_verify_optional);
}
itself.
*/
static int
-verify_callback_client_dane(int state, X509_STORE_CTX * x509ctx)
+verify_callback_client_dane(int preverify_ok, X509_STORE_CTX * x509ctx)
{
X509 * cert = X509_STORE_CTX_get_current_cert(x509ctx);
uschar dn[256];
-#ifdef EXPERIMENTAL_EVENT
int depth = X509_STORE_CTX_get_error_depth(x509ctx);
+#ifndef DISABLE_EVENT
BOOL dummy_called, optional = FALSE;
#endif
X509_NAME_oneline(X509_get_subject_name(cert), CS dn, sizeof(dn));
dn[sizeof(dn)-1] = '\0';
-DEBUG(D_tls) debug_printf("verify_callback_client_dane: %s\n", dn);
+DEBUG(D_tls) debug_printf("verify_callback_client_dane: %s depth %d %s\n",
+ preverify_ok ? "ok":"BAD", depth, dn);
-#ifdef EXPERIMENTAL_EVENT
+#ifndef DISABLE_EVENT
if (verify_event(&tls_out, cert, depth, dn,
&dummy_called, &optional, US"DANE"))
return 0; /* reject, with peercert set */
#endif
-if (state == 1)
+if (preverify_ok == 1)
tls_out.dane_verified =
tls_out.certificate_verified = TRUE;
-return 1;
+else
+ {
+ int err = X509_STORE_CTX_get_error(x509ctx);
+ DEBUG(D_tls)
+ debug_printf(" - err %d '%s'\n", err, X509_verify_cert_error_string(err));
+ if (err == X509_V_ERR_APPLICATION_VERIFICATION)
+ preverify_ok = 1;
+ }
+return preverify_ok;
}
#endif /*EXPERIMENTAL_DANE*/
sctx The current SSL CTX (inbound or outbound)
dhparam DH parameter file or fixed parameter identity string
host connected host, if client; NULL if server
+ errstr error string pointer
Returns: TRUE if OK (nothing to set up, or setup worked)
*/
static BOOL
-init_dh(SSL_CTX *sctx, uschar *dhparam, const host_item *host)
+init_dh(SSL_CTX *sctx, uschar *dhparam, const host_item *host, uschar ** errstr)
{
BIO *bio;
DH *dh;
uschar *dhexpanded;
const char *pem;
+int dh_bitsize;
-if (!expand_check(dhparam, US"tls_dhparam", &dhexpanded))
+if (!expand_check(dhparam, US"tls_dhparam", &dhexpanded, errstr))
return FALSE;
if (!dhexpanded || !*dhexpanded)
if (!(bio = BIO_new_file(CS dhexpanded, "r")))
{
tls_error(string_sprintf("could not read dhparams file %s", dhexpanded),
- host, US strerror(errno));
+ host, US strerror(errno), errstr);
return FALSE;
}
}
if (!(pem = std_dh_prime_named(dhexpanded)))
{
tls_error(string_sprintf("Unknown standard DH prime \"%s\"", dhexpanded),
- host, US strerror(errno));
+ host, US strerror(errno), errstr);
return FALSE;
}
bio = BIO_new_mem_buf(CS pem, -1);
{
BIO_free(bio);
tls_error(string_sprintf("Could not read tls_dhparams \"%s\"", dhexpanded),
- host, NULL);
+ host, NULL, errstr);
return FALSE;
}
+/* note: our default limit of 2236 is not a multiple of 8; the limit comes from
+ * an NSS limit, and the GnuTLS APIs handle bit-sizes fine, so we went with
+ * 2236. But older OpenSSL can only report in bytes (octets), not bits.
+ * If someone wants to dance at the edge, then they can raise the limit or use
+ * current libraries. */
+#ifdef EXIM_HAVE_OPENSSL_DH_BITS
+/* Added in commit 26c79d5641d; `git describe --contains` says OpenSSL_1_1_0-pre1~1022
+ * This predates OpenSSL_1_1_0 (before a, b, ...) so is in all 1.1.0 */
+dh_bitsize = DH_bits(dh);
+#else
+dh_bitsize = 8 * DH_size(dh);
+#endif
+
/* Even if it is larger, we silently return success rather than cause things
* to fail out, so that a too-large DH will not knock out all TLS; it's a
* debatable choice. */
-if ((8*DH_size(dh)) > tls_dh_max_bits)
+if (dh_bitsize > tls_dh_max_bits)
{
DEBUG(D_tls)
- debug_printf("dhparams file %d bits, is > tls_dh_max_bits limit of %d",
- 8*DH_size(dh), tls_dh_max_bits);
+ debug_printf("dhparams file %d bits, is > tls_dh_max_bits limit of %d\n",
+ dh_bitsize, tls_dh_max_bits);
}
else
{
SSL_CTX_set_tmp_dh(sctx, dh);
DEBUG(D_tls)
debug_printf("Diffie-Hellman initialized from %s with %d-bit prime\n",
- dhexpanded ? dhexpanded : US"default", 8*DH_size(dh));
+ dhexpanded ? dhexpanded : US"default", dh_bitsize);
}
DH_free(dh);
Arguments:
sctx The current SSL CTX (inbound or outbound)
host connected host, if client; NULL if server
+ errstr error string pointer
Returns: TRUE if OK (nothing to set up, or setup worked)
*/
static BOOL
-init_ecdh(SSL_CTX * sctx, host_item * host)
+init_ecdh(SSL_CTX * sctx, host_item * host, uschar ** errstr)
{
#ifdef OPENSSL_NO_ECDH
return TRUE;
return TRUE;
# else
-if (!expand_check(tls_eccurve, US"tls_eccurve", &exp_curve))
+if (!expand_check(tls_eccurve, US"tls_eccurve", &exp_curve, errstr))
return FALSE;
if (!exp_curve || !*exp_curve)
return TRUE;
-# ifdef EXIM_HAVE_OPENSSL_ECDH_AUTO
-/* check if new enough library to support auto ECDH temp key parameter selection */
+/* "auto" needs to be handled carefully.
+ * OpenSSL < 1.0.2: we do not select anything, but fallback to prime256v1
+ * OpenSSL < 1.1.0: we have to call SSL_CTX_set_ecdh_auto
+ * (openssl/ssl.h defines SSL_CTRL_SET_ECDH_AUTO)
+ * OpenSSL >= 1.1.0: we do not set anything, the libray does autoselection
+ * https://github.com/openssl/openssl/commit/fe6ef2472db933f01b59cad82aa925736935984b
+ */
if (Ustrcmp(exp_curve, "auto") == 0)
{
+#if OPENSSL_VERSION_NUMBER < 0x10002000L
+ DEBUG(D_tls) debug_printf(
+ "ECDH OpenSSL < 1.0.2: temp key parameter settings: overriding \"auto\" with \"prime256v1\"\n");
+ exp_curve = US"prime256v1";
+#else
+# if defined SSL_CTRL_SET_ECDH_AUTO
DEBUG(D_tls) debug_printf(
- "ECDH temp key parameter settings: OpenSSL 1.2+ autoselection\n");
+ "ECDH OpenSSL 1.0.2+ temp key parameter settings: autoselection\n");
SSL_CTX_set_ecdh_auto(sctx, 1);
return TRUE;
+# else
+ DEBUG(D_tls) debug_printf(
+ "ECDH OpenSSL 1.1.0+ temp key parameter settings: default selection\n");
+ return TRUE;
+# endif
+#endif
}
-# endif
DEBUG(D_tls) debug_printf("ECDH: curve '%s'\n", exp_curve);
if ( (nid = OBJ_sn2nid (CCS exp_curve)) == NID_undef
# endif
)
{
- tls_error(string_sprintf("Unknown curve name tls_eccurve '%s'",
- exp_curve),
- host, NULL);
+ tls_error(string_sprintf("Unknown curve name tls_eccurve '%s'", exp_curve),
+ host, NULL, errstr);
return FALSE;
}
if (!(ecdh = EC_KEY_new_by_curve_name(nid)))
{
- tls_error(US"Unable to create ec curve", host, NULL);
+ tls_error(US"Unable to create ec curve", host, NULL, errstr);
return FALSE;
}
not to the stability of the interface. */
if ((rv = SSL_CTX_set_tmp_ecdh(sctx, ecdh) == 0))
- tls_error(string_sprintf("Error enabling '%s' curve", exp_curve), host, NULL);
+ tls_error(string_sprintf("Error enabling '%s' curve", exp_curve), host, NULL, errstr);
else
DEBUG(D_tls) debug_printf("ECDH: enabled '%s' curve\n", exp_curve);
/*************************************************
* Load OCSP information into state *
*************************************************/
-
/* Called to load the server OCSP response from the given file into memory, once
caller has determined this is needed. Checks validity. Debugs a message
if invalid.
static void
ocsp_load_response(SSL_CTX *sctx, tls_ext_ctx_cb *cbinfo, const uschar *expanded)
{
-BIO *bio;
-OCSP_RESPONSE *resp;
-OCSP_BASICRESP *basic_response;
-OCSP_SINGLERESP *single_response;
-ASN1_GENERALIZEDTIME *rev, *thisupd, *nextupd;
-X509_STORE *store;
+BIO * bio;
+OCSP_RESPONSE * resp;
+OCSP_BASICRESP * basic_response;
+OCSP_SINGLERESP * single_response;
+ASN1_GENERALIZEDTIME * rev, * thisupd, * nextupd;
+STACK_OF(X509) * sk;
unsigned long verify_flags;
int status, reason, i;
cbinfo->u_ocsp.server.response = NULL;
}
-bio = BIO_new_file(CS cbinfo->u_ocsp.server.file_expanded, "rb");
-if (!bio)
+if (!(bio = BIO_new_file(CS cbinfo->u_ocsp.server.file_expanded, "rb")))
{
DEBUG(D_tls) debug_printf("Failed to open OCSP response file \"%s\"\n",
cbinfo->u_ocsp.server.file_expanded);
return;
}
-status = OCSP_response_status(resp);
-if (status != OCSP_RESPONSE_STATUS_SUCCESSFUL)
+if ((status = OCSP_response_status(resp)) != OCSP_RESPONSE_STATUS_SUCCESSFUL)
{
DEBUG(D_tls) debug_printf("OCSP response not valid: %s (%d)\n",
OCSP_response_status_str(status), status);
goto bad;
}
-basic_response = OCSP_response_get1_basic(resp);
-if (!basic_response)
+if (!(basic_response = OCSP_response_get1_basic(resp)))
{
DEBUG(D_tls)
debug_printf("OCSP response parse error: unable to extract basic response.\n");
goto bad;
}
-store = SSL_CTX_get_cert_store(sctx);
+sk = cbinfo->verify_stack;
verify_flags = OCSP_NOVERIFY; /* check sigs, but not purpose */
/* May need to expose ability to adjust those flags?
OCSP_NOSIGS OCSP_NOVERIFY OCSP_NOCHAIN OCSP_NOCHECKS OCSP_NOEXPLICIT
OCSP_TRUSTOTHER OCSP_NOINTERN */
-i = OCSP_basic_verify(basic_response, NULL, store, verify_flags);
-if (i <= 0)
+/* This does a full verify on the OCSP proof before we load it for serving
+up; possibly overkill - just date-checks might be nice enough.
+
+OCSP_basic_verify takes a "store" arg, but does not
+use it for the chain verification, which is all we do
+when OCSP_NOVERIFY is set. The content from the wire
+"basic_response" and a cert-stack "sk" are all that is used.
+
+We have a stack, loaded in setup_certs() if tls_verify_certificates
+was a file (not a directory, or "system"). It is unfortunate we
+cannot used the connection context store, as that would neatly
+handle the "system" case too, but there seems to be no library
+function for getting a stack from a store.
+[ In OpenSSL 1.1 - ? X509_STORE_CTX_get0_chain(ctx) ? ]
+We do not free the stack since it could be needed a second time for
+SNI handling.
+
+Separately we might try to replace using OCSP_basic_verify() - which seems to not
+be a public interface into the OpenSSL library (there's no manual entry) -
+But what with? We also use OCSP_basic_verify in the client stapling callback.
+And there we NEED it; we must verify that status... unless the
+library does it for us anyway? */
+
+if ((i = OCSP_basic_verify(basic_response, sk, NULL, verify_flags)) < 0)
{
- DEBUG(D_tls) {
+ DEBUG(D_tls)
+ {
ERR_error_string(ERR_get_error(), ssl_errstring);
debug_printf("OCSP response verify failure: %s\n", US ssl_errstring);
}
right cert in the stack and then calls OCSP_single_get0_status()).
I'm hoping to avoid reworking a bunch more of how we handle state here. */
-single_response = OCSP_resp_get0(basic_response, 0);
-if (!single_response)
+
+if (!(single_response = OCSP_resp_get0(basic_response, 0)))
{
DEBUG(D_tls)
debug_printf("Unable to get first response from OCSP basic response.\n");
{
extern char ** environ;
uschar ** p;
- for (p = USS environ; *p != NULL; p++)
+ if (environ) 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");
+/* Create and install a selfsigned certificate, for use in server mode */
+
+static int
+tls_install_selfsign(SSL_CTX * sctx, uschar ** errstr)
+{
+X509 * x509 = NULL;
+EVP_PKEY * pkey;
+RSA * rsa;
+X509_NAME * name;
+uschar * where;
+
+where = US"allocating pkey";
+if (!(pkey = EVP_PKEY_new()))
+ goto err;
+
+where = US"allocating cert";
+if (!(x509 = X509_new()))
+ goto err;
+
+where = US"generating pkey";
+ /* deprecated, use RSA_generate_key_ex() */
+if (!(rsa = RSA_generate_key(1024, RSA_F4, NULL, NULL)))
+ goto err;
+
+where = US"assigning pkey";
+if (!EVP_PKEY_assign_RSA(pkey, rsa))
+ goto err;
+
+X509_set_version(x509, 2); /* N+1 - version 3 */
+ASN1_INTEGER_set(X509_get_serialNumber(x509), 0);
+X509_gmtime_adj(X509_get_notBefore(x509), 0);
+X509_gmtime_adj(X509_get_notAfter(x509), (long)60 * 60); /* 1 hour */
+X509_set_pubkey(x509, pkey);
+
+name = X509_get_subject_name(x509);
+X509_NAME_add_entry_by_txt(name, "C",
+ MBSTRING_ASC, CUS "UK", -1, -1, 0);
+X509_NAME_add_entry_by_txt(name, "O",
+ MBSTRING_ASC, CUS "Exim Developers", -1, -1, 0);
+X509_NAME_add_entry_by_txt(name, "CN",
+ MBSTRING_ASC, CUS smtp_active_hostname, -1, -1, 0);
+X509_set_issuer_name(x509, name);
+
+where = US"signing cert";
+if (!X509_sign(x509, pkey, EVP_md5()))
+ goto err;
+
+where = US"installing selfsign cert";
+if (!SSL_CTX_use_certificate(sctx, x509))
+ goto err;
+
+where = US"installing selfsign key";
+if (!SSL_CTX_use_PrivateKey(sctx, pkey))
+ goto err;
+
+return OK;
+
+err:
+ (void) tls_error(where, NULL, NULL, errstr);
+ if (x509) X509_free(x509);
+ if (pkey) EVP_PKEY_free(pkey);
+ return DEFER;
+}
+
+
+
+
/*************************************************
* Expand key and cert file specs *
*************************************************/
Arguments:
sctx the SSL_CTX* to update
cbinfo various parts of session state
+ errstr error string pointer
Returns: OK/DEFER/FAIL
*/
static int
-tls_expand_session_files(SSL_CTX *sctx, tls_ext_ctx_cb *cbinfo)
+tls_expand_session_files(SSL_CTX *sctx, tls_ext_ctx_cb *cbinfo,
+ uschar ** errstr)
{
uschar *expanded;
-if (cbinfo->certificate == NULL)
- return OK;
-
-if (Ustrstr(cbinfo->certificate, US"tls_sni") ||
- Ustrstr(cbinfo->certificate, US"tls_in_sni") ||
- Ustrstr(cbinfo->certificate, US"tls_out_sni")
- )
- reexpand_tls_files_for_sni = TRUE;
-
-if (!expand_check(cbinfo->certificate, US"tls_certificate", &expanded))
- return DEFER;
-
-if (expanded != NULL)
+if (!cbinfo->certificate)
{
- DEBUG(D_tls) debug_printf("tls_certificate file %s\n", expanded);
- if (!SSL_CTX_use_certificate_chain_file(sctx, CS expanded))
- return tls_error(string_sprintf(
- "SSL_CTX_use_certificate_chain_file file=%s", expanded),
- cbinfo->host, NULL);
+ if (cbinfo->host) /* client */
+ return OK;
+ /* server */
+ if (tls_install_selfsign(sctx, errstr) != OK)
+ return DEFER;
}
+else
+ {
+ if (Ustrstr(cbinfo->certificate, US"tls_sni") ||
+ Ustrstr(cbinfo->certificate, US"tls_in_sni") ||
+ Ustrstr(cbinfo->certificate, US"tls_out_sni")
+ )
+ reexpand_tls_files_for_sni = TRUE;
-if (cbinfo->privatekey != NULL &&
- !expand_check(cbinfo->privatekey, US"tls_privatekey", &expanded))
- return DEFER;
+ if (!expand_check(cbinfo->certificate, US"tls_certificate", &expanded, errstr))
+ return DEFER;
-/* If expansion was forced to fail, key_expanded will be NULL. If the result
-of the expansion is an empty string, ignore it also, and assume the private
-key is in the same file as the certificate. */
+ if (expanded != NULL)
+ {
+ DEBUG(D_tls) debug_printf("tls_certificate file %s\n", expanded);
+ if (!SSL_CTX_use_certificate_chain_file(sctx, CS expanded))
+ return tls_error(string_sprintf(
+ "SSL_CTX_use_certificate_chain_file file=%s", expanded),
+ cbinfo->host, NULL, errstr);
+ }
-if (expanded != NULL && *expanded != 0)
- {
- DEBUG(D_tls) debug_printf("tls_privatekey file %s\n", expanded);
- if (!SSL_CTX_use_PrivateKey_file(sctx, CS expanded, SSL_FILETYPE_PEM))
- return tls_error(string_sprintf(
- "SSL_CTX_use_PrivateKey_file file=%s", expanded), cbinfo->host, NULL);
+ if (cbinfo->privatekey != NULL &&
+ !expand_check(cbinfo->privatekey, US"tls_privatekey", &expanded, errstr))
+ return DEFER;
+
+ /* If expansion was forced to fail, key_expanded will be NULL. If the result
+ of the expansion is an empty string, ignore it also, and assume the private
+ key is in the same file as the certificate. */
+
+ if (expanded && *expanded)
+ {
+ DEBUG(D_tls) debug_printf("tls_privatekey file %s\n", expanded);
+ if (!SSL_CTX_use_PrivateKey_file(sctx, CS expanded, SSL_FILETYPE_PEM))
+ return tls_error(string_sprintf(
+ "SSL_CTX_use_PrivateKey_file file=%s", expanded), cbinfo->host, NULL, errstr);
+ }
}
#ifndef DISABLE_OCSP
-if (cbinfo->is_server && cbinfo->u_ocsp.server.file != NULL)
+if (cbinfo->is_server && cbinfo->u_ocsp.server.file)
{
- if (!expand_check(cbinfo->u_ocsp.server.file, US"tls_ocsp_file", &expanded))
+ if (!expand_check(cbinfo->u_ocsp.server.file, US"tls_ocsp_file", &expanded, errstr))
return DEFER;
- if (expanded != NULL && *expanded != 0)
+ if (expanded && *expanded)
{
DEBUG(D_tls) debug_printf("tls_ocsp_file %s\n", expanded);
- if (cbinfo->u_ocsp.server.file_expanded &&
- (Ustrcmp(expanded, cbinfo->u_ocsp.server.file_expanded) == 0))
+ if ( cbinfo->u_ocsp.server.file_expanded
+ && (Ustrcmp(expanded, cbinfo->u_ocsp.server.file_expanded) == 0))
{
- DEBUG(D_tls)
- debug_printf("tls_ocsp_file value unchanged, using existing values.\n");
- } else {
- ocsp_load_response(sctx, cbinfo, expanded);
+ DEBUG(D_tls) debug_printf(" - value unchanged, using existing values\n");
}
+ else
+ ocsp_load_response(sctx, cbinfo, expanded);
}
}
#endif
tls_ext_ctx_cb *cbinfo = (tls_ext_ctx_cb *) arg;
int rc;
int old_pool = store_pool;
+uschar * dummy_errstr;
if (!servername)
return SSL_TLSEXT_ERR_OK;
SSL_CTX_set_tlsext_servername_callback(server_sni, tls_servername_cb);
SSL_CTX_set_tlsext_servername_arg(server_sni, cbinfo);
-if ( !init_dh(server_sni, cbinfo->dhparam, NULL)
- || !init_ecdh(server_sni, NULL)
+if ( !init_dh(server_sni, cbinfo->dhparam, NULL, &dummy_errstr)
+ || !init_ecdh(server_sni, NULL, &dummy_errstr)
)
return SSL_TLSEXT_ERR_NOACK;
}
#endif
-rc = setup_certs(server_sni, tls_verify_certificates, tls_crl, NULL, FALSE, verify_callback_server);
-if (rc != OK) return SSL_TLSEXT_ERR_NOACK;
+if ((rc = setup_certs(server_sni, tls_verify_certificates, tls_crl, NULL, FALSE,
+ verify_callback_server, &dummy_errstr)) != OK)
+ return SSL_TLSEXT_ERR_NOACK;
/* do this after setup_certs, because this can require the certs for verifying
OCSP information. */
-if ((rc = tls_expand_session_files(server_sni, cbinfo)) != OK)
+if ((rc = tls_expand_session_files(server_sni, cbinfo, &dummy_errstr)) != OK)
return SSL_TLSEXT_ERR_NOACK;
DEBUG(D_tls) debug_printf("Switching SSL context.\n");
/* 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,
+ if ((i = OCSP_basic_verify(bs, cbinfo->verify_stack,
cbinfo->u_ocsp.client.verify_store, 0)) <= 0)
{
tls_out.ocsp = OCSP_FAILED;
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 = cbinfo->u_ocsp.client.verify_required ? 0 : 1;
- goto out;
+ goto failed;
}
BIO_printf(bp, "OCSP response well-formed and signed OK\n");
+ /*XXX So we have a good stapled OCSP status. How do we know
+ it is for the cert of interest? OpenSSL 1.1.0 has a routine
+ OCSP_resp_find_status() which matches on a cert id, which presumably
+ we should use. Making an id needs OCSP_cert_id_new(), which takes
+ issuerName, issuerKey, serialNumber. Are they all in the cert?
+
+ For now, carry on blindly accepting the resp. */
+
{
- STACK_OF(OCSP_SINGLERESP) * sresp = bs->tbsResponseData->responses;
OCSP_SINGLERESP * single;
+#ifdef EXIM_HAVE_OCSP_RESP_COUNT
+ if (OCSP_resp_count(bs) != 1)
+#else
+ STACK_OF(OCSP_SINGLERESP) * sresp = bs->tbsResponseData->responses;
if (sk_OCSP_SINGLERESP_num(sresp) != 1)
+#endif
{
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;
+ goto failed;
}
single = OCSP_resp_get0(bs, 0);
status = OCSP_single_get0_status(single, &reason, &rev,
tls_out.ocsp = OCSP_FAILED;
DEBUG(D_tls) ERR_print_errors(bp);
log_write(0, LOG_MAIN, "Server OSCP dates invalid");
- i = cbinfo->u_ocsp.client.verify_required ? 0 : 1;
}
else
{
case V_OCSP_CERTSTATUS_GOOD:
tls_out.ocsp = OCSP_VFIED;
i = 1;
- break;
+ goto good;
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:
+ failed:
+ i = cbinfo->u_ocsp.client.verify_required ? 0 : 1;
+ good:
BIO_free(bp);
}
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
+ errstr error string pointer
Returns: OK/DEFER/FAIL
*/
#ifndef DISABLE_OCSP
uschar *ocsp_file,
#endif
- address_item *addr, tls_ext_ctx_cb ** cbp)
+ address_item *addr, tls_ext_ctx_cb ** cbp, uschar ** errstr)
{
+SSL_CTX * ctx;
long init_options;
int rc;
-BOOL okay;
tls_ext_ctx_cb * cbinfo;
cbinfo = store_malloc(sizeof(tls_ext_ctx_cb));
cbinfo->certificate = certificate;
cbinfo->privatekey = privatekey;
#ifndef DISABLE_OCSP
+cbinfo->verify_stack = NULL;
if ((cbinfo->is_server = host==NULL))
{
cbinfo->u_ocsp.server.file = ocsp_file;
cbinfo->dhparam = dhparam;
cbinfo->server_cipher_list = NULL;
cbinfo->host = host;
-#ifdef EXPERIMENTAL_EVENT
+#ifndef DISABLE_EVENT
cbinfo->event_action = NULL;
#endif
SSL_load_error_strings(); /* basic set up */
OpenSSL_add_ssl_algorithms();
-#if (OPENSSL_VERSION_NUMBER >= 0x0090800fL) && !defined(OPENSSL_NO_SHA256)
+#ifdef EXIM_HAVE_SHA256
/* SHA256 is becoming ever more popular. This makes sure it gets added to the
list of available digests. */
EVP_add_digest(EVP_sha256());
By disabling with openssl_options, we can let admins re-enable with the
existing knob. */
-*ctxp = SSL_CTX_new((host == NULL)?
- SSLv23_server_method() : SSLv23_client_method());
-
-if (*ctxp == NULL) return tls_error(US"SSL_CTX_new", host, NULL);
+if (!(ctx = SSL_CTX_new(host ? SSLv23_client_method() : SSLv23_server_method())))
+ return tls_error(US"SSL_CTX_new", host, NULL, errstr);
/* It turns out that we need to seed the random number generator this early in
order to get the full complement of ciphers to work. It took me roughly a day
if (!RAND_status())
return tls_error(US"RAND_status", host,
- US"unable to seed random number generator");
+ US"unable to seed random number generator", errstr);
}
/* Set up the information callback, which outputs if debugging is at a suitable
level. */
-DEBUG(D_tls) SSL_CTX_set_info_callback(*ctxp, (void (*)())info_callback);
+DEBUG(D_tls) SSL_CTX_set_info_callback(ctx, (void (*)())info_callback);
/* Automatically re-try reads/writes after renegotiation. */
-(void) SSL_CTX_set_mode(*ctxp, SSL_MODE_AUTO_RETRY);
+(void) SSL_CTX_set_mode(ctx, SSL_MODE_AUTO_RETRY);
/* Apply administrator-supplied work-arounds.
Historically we applied just one requested option,
No OpenSSL version number checks: the options we accept depend upon the
availability of the option value macros from OpenSSL. */
-okay = tls_openssl_options_parse(openssl_options, &init_options);
-if (!okay)
- return tls_error(US"openssl_options parsing failed", host, NULL);
+if (!tls_openssl_options_parse(openssl_options, &init_options))
+ return tls_error(US"openssl_options parsing failed", host, NULL, errstr);
if (init_options)
{
DEBUG(D_tls) debug_printf("setting SSL CTX options: %#lx\n", init_options);
- if (!(SSL_CTX_set_options(*ctxp, init_options)))
+ if (!(SSL_CTX_set_options(ctx, init_options)))
return tls_error(string_sprintf(
- "SSL_CTX_set_option(%#lx)", init_options), host, NULL);
+ "SSL_CTX_set_option(%#lx)", init_options), host, NULL, errstr);
}
else
DEBUG(D_tls) debug_printf("no SSL CTX options to set\n");
+/* Disable session cache unconditionally */
+
+(void) SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_OFF);
+
/* Initialize with DH parameters if supplied */
/* Initialize ECDH temp key parameter selection */
-if ( !init_dh(*ctxp, dhparam, host)
- || !init_ecdh(*ctxp, host)
+if ( !init_dh(ctx, dhparam, host, errstr)
+ || !init_ecdh(ctx, host, errstr)
)
return DEFER;
/* Set up certificate and key (and perhaps OCSP info) */
-rc = tls_expand_session_files(*ctxp, cbinfo);
-if (rc != OK) return rc;
+if ((rc = tls_expand_session_files(ctx, cbinfo, errstr)) != OK)
+ return rc;
+
+/* If we need to handle SNI or OCSP, do so */
-/* If we need to handle SNI, do so */
#ifdef EXIM_HAVE_OPENSSL_TLSEXT
+# ifndef DISABLE_OCSP
+ if (!(cbinfo->verify_stack = sk_X509_new_null()))
+ {
+ DEBUG(D_tls) debug_printf("failed to create stack for stapling verify\n");
+ return FAIL;
+ }
+# endif
+
if (host == NULL) /* server */
{
# ifndef DISABLE_OCSP
callback is invoked. */
if (cbinfo->u_ocsp.server.file)
{
- SSL_CTX_set_tlsext_status_cb(server_ctx, tls_server_stapling_cb);
- SSL_CTX_set_tlsext_status_arg(server_ctx, cbinfo);
+ SSL_CTX_set_tlsext_status_cb(ctx, tls_server_stapling_cb);
+ SSL_CTX_set_tlsext_status_arg(ctx, cbinfo);
}
# endif
/* We always do this, so that $tls_sni is available even if not used in
tls_certificate */
- SSL_CTX_set_tlsext_servername_callback(*ctxp, tls_servername_cb);
- SSL_CTX_set_tlsext_servername_arg(*ctxp, cbinfo);
+ SSL_CTX_set_tlsext_servername_callback(ctx, tls_servername_cb);
+ SSL_CTX_set_tlsext_servername_arg(ctx, cbinfo);
}
# ifndef DISABLE_OCSP
else /* client */
DEBUG(D_tls) debug_printf("failed to create store for stapling verify\n");
return FAIL;
}
- SSL_CTX_set_tlsext_status_cb(*ctxp, tls_client_stapling_cb);
- SSL_CTX_set_tlsext_status_arg(*ctxp, cbinfo);
+ SSL_CTX_set_tlsext_status_cb(ctx, tls_client_stapling_cb);
+ SSL_CTX_set_tlsext_status_arg(ctx, cbinfo);
}
# endif
#endif
cbinfo->verify_cert_hostnames = NULL;
+#ifdef EXIM_HAVE_EPHEM_RSA_KEX
/* Set up the RSA callback */
-
-SSL_CTX_set_tmp_rsa_callback(*ctxp, rsa_callback);
+SSL_CTX_set_tmp_rsa_callback(ctx, rsa_callback);
+#endif
/* Finally, set the timeout, and we are done */
-SSL_CTX_set_timeout(*ctxp, ssl_session_timeout);
+SSL_CTX_set_timeout(ctx, ssl_session_timeout);
DEBUG(D_tls) debug_printf("Initialized TLS\n");
*cbp = cbinfo;
+*ctxp = ctx;
return OK;
}
* Set up for verifying certificates *
*************************************************/
+/* Load certs from file, return TRUE on success */
+
+static BOOL
+chain_from_pem_file(const uschar * file, STACK_OF(X509) * verify_stack)
+{
+BIO * bp;
+X509 * x;
+
+if (!(bp = BIO_new_file(CS file, "r"))) return FALSE;
+while ((x = PEM_read_bio_X509(bp, NULL, 0, NULL)))
+ sk_X509_push(verify_stack, x);
+BIO_free(bp);
+return TRUE;
+}
+
+
+
/* Called by both client and server startup
Arguments:
optional TRUE if called from a server for a host in tls_try_verify_hosts;
otherwise passed as FALSE
cert_vfy_cb Callback function for certificate verification
+ errstr error string pointer
Returns: OK/DEFER/FAIL
*/
static int
setup_certs(SSL_CTX *sctx, uschar *certs, uschar *crl, host_item *host, BOOL optional,
- int (*cert_vfy_cb)(int, X509_STORE_CTX *) )
+ int (*cert_vfy_cb)(int, X509_STORE_CTX *), uschar ** errstr)
{
uschar *expcerts, *expcrl;
-if (!expand_check(certs, US"tls_verify_certificates", &expcerts))
+if (!expand_check(certs, US"tls_verify_certificates", &expcerts, errstr))
return DEFER;
+DEBUG(D_tls) debug_printf("tls_verify_certificates: %s\n", expcerts);
-if (expcerts != NULL && *expcerts != '\0')
+if (expcerts && *expcerts)
{
- if (Ustrcmp(expcerts, "system") == 0)
- {
- /* Tell the library to use its compiled-in location for the system default
- CA bundle, only */
+ /* Tell the library to use its compiled-in location for the system default
+ CA bundle. Then add the ones specified in the config, if any. */
- if (!SSL_CTX_set_default_verify_paths(sctx))
- return tls_error(US"SSL_CTX_set_default_verify_paths", host, NULL);
- }
- else
+ if (!SSL_CTX_set_default_verify_paths(sctx))
+ return tls_error(US"SSL_CTX_set_default_verify_paths", host, NULL, errstr);
+
+ if (Ustrcmp(expcerts, "system") != 0)
{
struct stat statbuf;
- /* Tell the library to use its compiled-in location for the system default
- CA bundle. Those given by the exim config are additional to these */
-
- if (!SSL_CTX_set_default_verify_paths(sctx))
- return tls_error(US"SSL_CTX_set_default_verify_paths", host, NULL);
-
if (Ustat(expcerts, &statbuf) < 0)
{
log_write(0, LOG_MAIN|LOG_PANIC,
if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
{ file = NULL; dir = expcerts; }
else
- { file = expcerts; dir = NULL; }
+ {
+ file = expcerts; dir = NULL;
+#ifndef DISABLE_OCSP
+ /* In the server if we will be offering an OCSP proof, load chain from
+ file for verifying the OCSP proof at load time. */
+
+ if ( !host
+ && statbuf.st_size > 0
+ && server_static_cbinfo->u_ocsp.server.file
+ && !chain_from_pem_file(file, server_static_cbinfo->verify_stack)
+ )
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC,
+ "failed to load cert hain from %s", file);
+ return DEFER;
+ }
+#endif
+ }
/* If a certificate file is empty, the next function fails with an
unhelpful error message. If we skip it, we get the correct behaviour (no
certificates are recognized, but the error message is still misleading (it
- says no certificate was supplied.) But this is better. */
+ says no certificate was supplied). But this is better. */
- if ((file == NULL || statbuf.st_size > 0) &&
- !SSL_CTX_load_verify_locations(sctx, CS file, CS dir))
- return tls_error(US"SSL_CTX_load_verify_locations", host, NULL);
+ if ( (!file || statbuf.st_size > 0)
+ && !SSL_CTX_load_verify_locations(sctx, CS file, CS dir))
+ return tls_error(US"SSL_CTX_load_verify_locations", host, NULL, errstr);
/* 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
+ a wildcard request for client certs.
+ Meanwhile, the client library as default 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)
+ if (file)
{
STACK_OF(X509_NAME) * names = SSL_load_client_CA_file(CS file);
- DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n",
+
+ DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n",
sk_X509_NAME_num(names));
SSL_CTX_set_client_CA_list(sctx, names);
}
/* Handle a certificate revocation list. */
- #if OPENSSL_VERSION_NUMBER > 0x00907000L
+#if OPENSSL_VERSION_NUMBER > 0x00907000L
/* This bit of code is now the version supplied by Lars Mainka. (I have
- * merely reformatted it into the Exim code style.)
+ merely reformatted it into the Exim code style.)
- * "From here I changed the code to add support for multiple crl's
- * in pem format in one file or to support hashed directory entries in
- * pem format instead of a file. This method now uses the library function
- * X509_STORE_load_locations to add the CRL location to the SSL context.
- * OpenSSL will then handle the verify against CA certs and CRLs by
- * itself in the verify callback." */
+ "From here I changed the code to add support for multiple crl's
+ in pem format in one file or to support hashed directory entries in
+ pem format instead of a file. This method now uses the library function
+ X509_STORE_load_locations to add the CRL location to the SSL context.
+ OpenSSL will then handle the verify against CA certs and CRLs by
+ itself in the verify callback." */
- if (!expand_check(crl, US"tls_crl", &expcrl)) return DEFER;
- if (expcrl != NULL && *expcrl != 0)
+ if (!expand_check(crl, US"tls_crl", &expcrl, errstr)) return DEFER;
+ if (expcrl && *expcrl)
{
struct stat statbufcrl;
if (Ustat(expcrl, &statbufcrl) < 0)
DEBUG(D_tls) debug_printf("SSL CRL value is a file %s\n", file);
}
if (X509_STORE_load_locations(cvstore, CS file, CS dir) == 0)
- return tls_error(US"X509_STORE_load_locations", host, NULL);
+ return tls_error(US"X509_STORE_load_locations", host, NULL, errstr);
/* setting the flags to check against the complete crl chain */
}
}
- #endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
+#endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
/* If verification is optional, don't fail if no certificate */
Arguments:
require_ciphers allowed ciphers
+ errstr pointer to error message
Returns: OK on success
DEFER for errors before the start of the negotiation
- FAIL for errors during the negotation; the server can't
+ FAIL for errors during the negotiation; the server can't
continue running.
*/
int
-tls_server_start(const uschar *require_ciphers)
+tls_server_start(const uschar * require_ciphers, uschar ** errstr)
{
int rc;
-uschar *expciphers;
-tls_ext_ctx_cb *cbinfo;
+uschar * expciphers;
+tls_ext_ctx_cb * cbinfo;
static uschar peerdn[256];
static uschar cipherbuf[256];
if (tls_in.active >= 0)
{
- tls_error(US"STARTTLS received after TLS started", NULL, US"");
- smtp_printf("554 Already in TLS\r\n");
+ tls_error(US"STARTTLS received after TLS started", NULL, US"", errstr);
+ smtp_printf("554 Already in TLS\r\n", FALSE);
return FAIL;
}
#ifndef DISABLE_OCSP
tls_ocsp_file,
#endif
- NULL, &server_static_cbinfo);
+ NULL, &server_static_cbinfo, errstr);
if (rc != OK) return rc;
cbinfo = server_static_cbinfo;
-if (!expand_check(require_ciphers, US"tls_require_ciphers", &expciphers))
+if (!expand_check(require_ciphers, US"tls_require_ciphers", &expciphers, errstr))
return FAIL;
/* In OpenSSL, cipher components are separated by hyphens. In GnuTLS, they
tests, and also for general convenience, we turn underscores into hyphens here.
*/
-if (expciphers != NULL)
+if (expciphers)
{
- uschar *s = expciphers;
+ uschar * s = expciphers;
while (*s != 0) { if (*s == '_') *s = '-'; s++; }
DEBUG(D_tls) debug_printf("required ciphers: %s\n", expciphers);
if (!SSL_CTX_set_cipher_list(server_ctx, CS expciphers))
- return tls_error(US"SSL_CTX_set_cipher_list", NULL, NULL);
+ return tls_error(US"SSL_CTX_set_cipher_list", NULL, NULL, errstr);
cbinfo->server_cipher_list = expciphers;
}
if (verify_check_host(&tls_verify_hosts) == OK)
{
rc = setup_certs(server_ctx, tls_verify_certificates, tls_crl, NULL,
- FALSE, verify_callback_server);
+ FALSE, verify_callback_server, errstr);
if (rc != OK) return rc;
server_verify_optional = FALSE;
}
else if (verify_check_host(&tls_try_verify_hosts) == OK)
{
rc = setup_certs(server_ctx, tls_verify_certificates, tls_crl, NULL,
- TRUE, verify_callback_server);
+ TRUE, verify_callback_server, errstr);
if (rc != OK) return rc;
server_verify_optional = TRUE;
}
/* Prepare for new connection */
-if ((server_ssl = SSL_new(server_ctx)) == NULL) return tls_error(US"SSL_new", NULL, NULL);
+if (!(server_ssl = SSL_new(server_ctx)))
+ return tls_error(US"SSL_new", NULL, NULL, errstr);
/* Warning: we used to SSL_clear(ssl) here, it was removed.
*
SSL_set_session_id_context(server_ssl, sid_ctx, Ustrlen(sid_ctx));
if (!tls_in.on_connect)
{
- smtp_printf("220 TLS go ahead\r\n");
+ smtp_printf("220 TLS go ahead\r\n", FALSE);
fflush(smtp_out);
}
if (rc <= 0)
{
- tls_error(US"SSL_accept", NULL, sigalrm_seen ? US"timed out" : NULL);
- if (ERR_get_error() == 0)
- log_write(0, LOG_MAIN,
- "TLS client disconnected cleanly (rejected our certificate?)");
+ (void) tls_error(US"SSL_accept", NULL, sigalrm_seen ? US"timed out" : NULL, errstr);
return FAIL;
}
ssl_xfer_eof = ssl_xfer_error = 0;
receive_getc = tls_getc;
+receive_getbuf = tls_getbuf;
+receive_get_cache = tls_get_cache;
receive_ungetc = tls_ungetc;
receive_feof = tls_feof;
receive_ferror = tls_ferror;
static int
tls_client_basic_ctx_init(SSL_CTX * ctx,
- host_item * host, smtp_transport_options_block * ob, tls_ext_ctx_cb * cbinfo
- )
+ host_item * host, smtp_transport_options_block * ob, tls_ext_ctx_cb * cbinfo,
+ uschar ** errstr)
{
int rc;
/* stick to the old behaviour for compatibility if tls_verify_certificates is
return OK;
if ((rc = setup_certs(ctx, ob->tls_verify_certificates,
- ob->tls_crl, host, client_verify_optional, verify_callback_client)) != OK)
+ ob->tls_crl, host, client_verify_optional, verify_callback_client,
+ errstr)) != OK)
return rc;
if (verify_check_given_host(&ob->tls_verify_cert_hostnames, host) == OK)
{
cbinfo->verify_cert_hostnames =
-#ifdef EXPERIMENTAL_INTERNATIONAL
+#ifdef SUPPORT_I18N
string_domain_utf8_to_alabel(host->name, NULL);
#else
host->name;
#ifdef EXPERIMENTAL_DANE
static int
-dane_tlsa_load(SSL * ssl, host_item * host, dns_answer * dnsa)
+dane_tlsa_load(SSL * ssl, host_item * host, dns_answer * dnsa, uschar ** errstr)
{
dns_record * rr;
dns_scan dnss;
int found = 0;
if (DANESSL_init(ssl, NULL, hostnames) != 1)
- return tls_error(US"hostnames load", host, NULL);
+ return tls_error(US"hostnames load", host, NULL, errstr);
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;
+ const uschar * p = rr->data;
uint8_t usage, selector, mtype;
const char * mdname;
switch (DANESSL_add_tlsa(ssl, usage, selector, mdname, p, rr->size - 3))
{
default:
+ return tls_error(US"tlsa load", host, NULL, errstr);
case 0: /* action not taken */
- return tls_error(US"tlsa load", host, NULL);
case 1: break;
}
addr the first address
tb transport (always smtp)
tlsa_dnsa tlsa lookup, if DANE, else null
+ errstr error string pointer
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,
- transport_instance *tb
+ transport_instance * tb,
#ifdef EXPERIMENTAL_DANE
- , dns_answer * tlsa_dnsa
+ dns_answer * tlsa_dnsa,
#endif
- )
+ uschar ** errstr)
{
smtp_transport_options_block * ob =
(smtp_transport_options_block *)tb->options_block;
#ifndef DISABLE_OCSP
(void *)(long)request_ocsp,
#endif
- addr, &client_static_cbinfo);
+ addr, &client_static_cbinfo, errstr);
if (rc != OK) return rc;
tls_out.certificate_verified = FALSE;
client_verify_callback_called = FALSE;
if (!expand_check(ob->tls_require_ciphers, US"tls_require_ciphers",
- &expciphers))
+ &expciphers, errstr))
return FAIL;
/* In OpenSSL, cipher components are separated by hyphens. In GnuTLS, they
are separated by underscores. So that I can use either form in my tests, and
also for general convenience, we turn underscores into hyphens here. */
-if (expciphers != NULL)
+if (expciphers)
{
uschar *s = expciphers;
- while (*s != 0) { if (*s == '_') *s = '-'; s++; }
+ while (*s) { if (*s == '_') *s = '-'; s++; }
DEBUG(D_tls) debug_printf("required ciphers: %s\n", expciphers);
if (!SSL_CTX_set_cipher_list(client_ctx, CS expciphers))
- return tls_error(US"SSL_CTX_set_cipher_list", host, NULL);
+ return tls_error(US"SSL_CTX_set_cipher_list", host, NULL, errstr);
}
#ifdef EXPERIMENTAL_DANE
verify_callback_client_dane);
if (!DANESSL_library_init())
- return tls_error(US"library init", host, NULL);
+ return tls_error(US"library init", host, NULL, errstr);
if (DANESSL_CTX_init(client_ctx) <= 0)
- return tls_error(US"context init", host, NULL);
+ return tls_error(US"context init", host, NULL, errstr);
}
else
#endif
- if ((rc = tls_client_basic_ctx_init(client_ctx, host, ob, client_static_cbinfo))
- != OK)
+ if ((rc = tls_client_basic_ctx_init(client_ctx, host, ob,
+ client_static_cbinfo, errstr)) != OK)
return rc;
if ((client_ssl = SSL_new(client_ctx)) == NULL)
- return tls_error(US"SSL_new", host, NULL);
+ return tls_error(US"SSL_new", host, NULL, errstr);
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 (ob->tls_sni)
{
- if (!expand_check(ob->tls_sni, US"tls_sni", &tls_out.sni))
+ if (!expand_check(ob->tls_sni, US"tls_sni", &tls_out.sni, errstr))
return FAIL;
- if (tls_out.sni == NULL)
+ if (!tls_out.sni)
{
DEBUG(D_tls) debug_printf("Setting TLS SNI forced to fail, not sending\n");
}
DEBUG(D_tls) debug_printf("Setting TLS SNI \"%s\"\n", tls_out.sni);
SSL_set_tlsext_host_name(client_ssl, tls_out.sni);
#else
- DEBUG(D_tls)
- debug_printf("OpenSSL at build-time lacked SNI support, ignoring \"%s\"\n",
+ log_write(0, LOG_MAIN, "SNI unusable with this OpenSSL library version; ignoring \"%s\"\n",
tls_out.sni);
#endif
}
#ifdef EXPERIMENTAL_DANE
if (tlsa_dnsa)
- if ((rc = dane_tlsa_load(client_ssl, host, tlsa_dnsa)) != OK)
+ if ((rc = dane_tlsa_load(client_ssl, host, tlsa_dnsa, errstr)) != OK)
return rc;
#endif
}
#endif
-#ifdef EXPERIMENTAL_EVENT
+#ifndef DISABLE_EVENT
client_static_cbinfo->event_action = tb->event_action;
#endif
#endif
if (rc <= 0)
- return tls_error(US"SSL_connect", host, sigalrm_seen ? US"timed out" : NULL);
+ return tls_error(US"SSL_connect", host, sigalrm_seen ? US"timed out" : NULL,
+ errstr);
DEBUG(D_tls) debug_printf("SSL_connect succeeded\n");
+static BOOL
+tls_refill(unsigned lim)
+{
+int error;
+int inbytes;
+
+DEBUG(D_tls) debug_printf("Calling SSL_read(%p, %p, %u)\n", server_ssl,
+ ssl_xfer_buffer, ssl_xfer_buffer_size);
+
+if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
+inbytes = SSL_read(server_ssl, CS ssl_xfer_buffer,
+ MIN(ssl_xfer_buffer_size, lim));
+error = SSL_get_error(server_ssl, inbytes);
+alarm(0);
+
+/* SSL_ERROR_ZERO_RETURN appears to mean that the SSL session has been
+closed down, not that the socket itself has been closed down. Revert to
+non-SSL handling. */
+
+if (error == SSL_ERROR_ZERO_RETURN)
+ {
+ DEBUG(D_tls) debug_printf("Got SSL_ERROR_ZERO_RETURN\n");
+
+ receive_getc = smtp_getc;
+ receive_getbuf = smtp_getbuf;
+ receive_get_cache = smtp_get_cache;
+ receive_ungetc = smtp_ungetc;
+ receive_feof = smtp_feof;
+ receive_ferror = smtp_ferror;
+ receive_smtp_buffered = smtp_buffered;
+
+ SSL_free(server_ssl);
+ server_ssl = NULL;
+ tls_in.active = -1;
+ tls_in.bits = 0;
+ tls_in.cipher = NULL;
+ tls_in.peerdn = NULL;
+ tls_in.sni = NULL;
+
+ return FALSE;
+ }
+
+/* Handle genuine errors */
+
+else if (error == SSL_ERROR_SSL)
+ {
+ ERR_error_string(ERR_get_error(), ssl_errstring);
+ log_write(0, LOG_MAIN, "TLS error (SSL_read): %s", ssl_errstring);
+ ssl_xfer_error = 1;
+ return FALSE;
+ }
+
+else if (error != SSL_ERROR_NONE)
+ {
+ DEBUG(D_tls) debug_printf("Got SSL error %d\n", error);
+ ssl_xfer_error = 1;
+ return FALSE;
+ }
+
+#ifndef DISABLE_DKIM
+dkim_exim_verify_feed(ssl_xfer_buffer, inbytes);
+#endif
+ssl_xfer_buffer_hwm = inbytes;
+ssl_xfer_buffer_lwm = 0;
+return TRUE;
+}
+
+
/*************************************************
* TLS version of getc *
*************************************************/
/* This gets the next byte from the TLS input buffer. If the buffer is empty,
it refills the buffer via the SSL reading function.
-Arguments: none
+Arguments: lim Maximum amount to read/buffer
Returns: the next character or EOF
Only used by the server-side TLS.
*/
int
-tls_getc(void)
+tls_getc(unsigned lim)
{
if (ssl_xfer_buffer_lwm >= ssl_xfer_buffer_hwm)
- {
- int error;
- int inbytes;
+ if (!tls_refill(lim))
+ return ssl_xfer_error ? EOF : smtp_getc(lim);
- DEBUG(D_tls) debug_printf("Calling SSL_read(%p, %p, %u)\n", server_ssl,
- ssl_xfer_buffer, ssl_xfer_buffer_size);
+/* Something in the buffer; return next uschar */
- if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
- inbytes = SSL_read(server_ssl, CS ssl_xfer_buffer, ssl_xfer_buffer_size);
- error = SSL_get_error(server_ssl, inbytes);
- alarm(0);
+return ssl_xfer_buffer[ssl_xfer_buffer_lwm++];
+}
- /* SSL_ERROR_ZERO_RETURN appears to mean that the SSL session has been
- closed down, not that the socket itself has been closed down. Revert to
- non-SSL handling. */
+uschar *
+tls_getbuf(unsigned * len)
+{
+unsigned size;
+uschar * buf;
- if (error == SSL_ERROR_ZERO_RETURN)
+if (ssl_xfer_buffer_lwm >= ssl_xfer_buffer_hwm)
+ if (!tls_refill(*len))
{
- DEBUG(D_tls) debug_printf("Got SSL_ERROR_ZERO_RETURN\n");
-
- receive_getc = smtp_getc;
- receive_ungetc = smtp_ungetc;
- receive_feof = smtp_feof;
- receive_ferror = smtp_ferror;
- receive_smtp_buffered = smtp_buffered;
-
- SSL_free(server_ssl);
- server_ssl = NULL;
- tls_in.active = -1;
- tls_in.bits = 0;
- tls_in.cipher = NULL;
- tls_in.peerdn = NULL;
- tls_in.sni = NULL;
-
- return smtp_getc();
+ if (!ssl_xfer_error) return smtp_getbuf(len);
+ *len = 0;
+ return NULL;
}
- /* Handle genuine errors */
-
- else if (error == SSL_ERROR_SSL)
- {
- ERR_error_string(ERR_get_error(), ssl_errstring);
- log_write(0, LOG_MAIN, "TLS error (SSL_read): %s", ssl_errstring);
- ssl_xfer_error = 1;
- return EOF;
- }
+if ((size = ssl_xfer_buffer_hwm - ssl_xfer_buffer_lwm) > *len)
+ size = *len;
+buf = &ssl_xfer_buffer[ssl_xfer_buffer_lwm];
+ssl_xfer_buffer_lwm += size;
+*len = size;
+return buf;
+}
- else if (error != SSL_ERROR_NONE)
- {
- DEBUG(D_tls) debug_printf("Got SSL error %d\n", error);
- ssl_xfer_error = 1;
- return EOF;
- }
+void
+tls_get_cache()
+{
#ifndef DISABLE_DKIM
- dkim_exim_verify_feed(ssl_xfer_buffer, inbytes);
+int n = ssl_xfer_buffer_hwm - ssl_xfer_buffer_lwm;
+if (n > 0)
+ dkim_exim_verify_feed(ssl_xfer_buffer+ssl_xfer_buffer_lwm, n);
#endif
- ssl_xfer_buffer_hwm = inbytes;
- ssl_xfer_buffer_lwm = 0;
- }
+}
-/* Something in the buffer; return next uschar */
-return ssl_xfer_buffer[ssl_xfer_buffer_lwm++];
+BOOL
+tls_could_read(void)
+{
+return ssl_xfer_buffer_lwm < ssl_xfer_buffer_hwm || SSL_pending(server_ssl) > 0;
}
-
/*************************************************
* Read bytes from TLS channel *
*************************************************/
return -1;
}
else if (error != SSL_ERROR_NONE)
- {
return -1;
- }
return inbytes;
}
is_server channel specifier
buff buffer of data
len number of bytes
+ more further data expected soon
Returns: the number of bytes after a successful write,
-1 after a failed write
*/
int
-tls_write(BOOL is_server, const uschar *buff, size_t len)
+tls_write(BOOL is_server, const uschar *buff, size_t len, BOOL more)
{
-int outbytes;
-int error;
-int left = len;
+int outbytes, error, left;
SSL *ssl = is_server ? server_ssl : client_ssl;
+static uschar * corked = NULL;
+static int c_size = 0, c_len = 0;
+
+DEBUG(D_tls) debug_printf("%s(%p, %d%s)\n", __FUNCTION__,
+ buff, left, more ? ", more" : "");
+
+/* Lacking a CORK or MSG_MORE facility (such as GnuTLS has) we copy data when
+"more" is notified. This hack is only ok if small amounts are involved AND only
+one stream does it, in one context (i.e. no store reset). Currently it is used
+for the responses to the received SMTP MAIL , RCPT, DATA sequence, only. */
-DEBUG(D_tls) debug_printf("tls_do_write(%p, %d)\n", buff, left);
-while (left > 0)
+if (is_server && (more || corked))
+ {
+ corked = string_catn(corked, &c_size, &c_len, buff, len);
+ if (more)
+ return len;
+ buff = CUS corked;
+ len = c_len;
+ corked = NULL; c_size = c_len = 0;
+ }
+
+for (left = len; left > 0;)
{
DEBUG(D_tls) debug_printf("SSL_write(SSL, %p, %d)\n", buff, left);
outbytes = SSL_write(ssl, CS buff, left);
switch (error)
{
case SSL_ERROR_SSL:
- ERR_error_string(ERR_get_error(), ssl_errstring);
- log_write(0, LOG_MAIN, "TLS error (SSL_write): %s", ssl_errstring);
- return -1;
+ ERR_error_string(ERR_get_error(), ssl_errstring);
+ log_write(0, LOG_MAIN, "TLS error (SSL_write): %s", ssl_errstring);
+ return -1;
case SSL_ERROR_NONE:
- left -= outbytes;
- buff += outbytes;
- break;
+ left -= outbytes;
+ buff += outbytes;
+ break;
case SSL_ERROR_ZERO_RETURN:
- log_write(0, LOG_MAIN, "SSL channel closed on write");
- return -1;
+ log_write(0, LOG_MAIN, "SSL channel closed on write");
+ return -1;
case SSL_ERROR_SYSCALL:
- log_write(0, LOG_MAIN, "SSL_write: (from %s) syscall: %s",
- sender_fullhost ? sender_fullhost : US"<unknown>",
- strerror(errno));
+ log_write(0, LOG_MAIN, "SSL_write: (from %s) syscall: %s",
+ sender_fullhost ? sender_fullhost : US"<unknown>",
+ strerror(errno));
+ return -1;
default:
- log_write(0, LOG_MAIN, "SSL_write error %d", error);
- return -1;
+ log_write(0, LOG_MAIN, "SSL_write error %d", error);
+ return -1;
}
}
return len;
if (!(tls_require_ciphers && *tls_require_ciphers))
return NULL;
-if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers))
+if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers,
+ &err))
return US"failed to expand tls_require_ciphers";
if (!(expciphers && *expciphers))
if (!SSL_CTX_set_cipher_list(ctx, CS expciphers))
{
ERR_error_string(ERR_get_error(), ssl_errstring);
- err = string_sprintf("SSL_CTX_set_cipher_list(%s) failed", expciphers);
+ err = string_sprintf("SSL_CTX_set_cipher_list(%s) failed: %s",
+ expciphers, ssl_errstring);
}
SSL_CTX_free(ctx);
if (i < needed_len)
needed_len = i;
+#ifdef EXIM_HAVE_RAND_PSEUDO
/* We do not care if crypto-strong */
i = RAND_pseudo_bytes(smallbuf, needed_len);
+#else
+i = RAND_bytes(smallbuf, needed_len);
+#endif
+
if (i < 0)
{
DEBUG(D_all)
uschar keep_c;
BOOL adding, item_parsed;
-result = 0L;
+result = SSL_OP_NO_TICKET;
/* Prior to 4.80 we or'd in SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS; removed
* from default because it increases BEAST susceptibility. */
#ifdef SSL_OP_NO_SSLv2
result |= SSL_OP_NO_SSLv2;
#endif
+#ifdef SSL_OP_SINGLE_DH_USE
+result |= SSL_OP_SINGLE_DH_USE;
+#endif
-if (option_spec == NULL)
+if (!option_spec)
{
*results = result;
return TRUE;
keep_c = *end;
*end = '\0';
item_parsed = tls_openssl_one_option_parse(s, &item);
+ *end = keep_c;
if (!item_parsed)
{
DEBUG(D_tls) debug_printf("openssl option setting unrecognised: \"%s\"\n", s);
result |= item;
else
result &= ~item;
- *end = keep_c;
s = end;
}