* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2017 */
+/* Copyright (c) University of Cambridge 1995 - 2018 */
/* See the file NOTICE for conditions of use and distribution. */
/* Copyright (c) Phil Pennock 2012 */
#include <gnutls/x509.h>
/* man-page is incorrect, gnutls_rnd() is not in gnutls.h: */
#include <gnutls/crypto.h>
+
/* needed to disable PKCS11 autoload unless requested */
#if GNUTLS_VERSION_NUMBER >= 0x020c00
# include <gnutls/pkcs11.h>
#if GNUTLS_VERSION_NUMBER >= 0x030014
# define SUPPORT_SYSDEFAULT_CABUNDLE
#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030104
+# define GNUTLS_CERT_VFY_STATUS_PRINT
+#endif
#if GNUTLS_VERSION_NUMBER >= 0x030109
# define SUPPORT_CORK
#endif
+#if GNUTLS_VERSION_NUMBER >= 0x03010a
+# define SUPPORT_GNUTLS_SESS_DESC
+#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030500
+# define SUPPORT_GNUTLS_KEYLOG
+#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030506 && !defined(DISABLE_OCSP)
+# define SUPPORT_SRV_OCSP_STACK
+#endif
+
+#ifdef SUPPORT_DANE
+# if GNUTLS_VERSION_NUMBER >= 0x030000
+# define DANESSL_USAGE_DANE_TA 2
+# define DANESSL_USAGE_DANE_EE 3
+# else
+# error GnuTLS version too early for DANE
+# endif
+# if GNUTLS_VERSION_NUMBER < 0x999999
+# define GNUTLS_BROKEN_DANE_VALIDATION
+# endif
+#endif
+
+#ifdef EXPERIMENTAL_TLS_RESUME
+# if GNUTLS_VERSION_NUMBER < 0x030603
+# error GNUTLS version too early for session-resumption
+# endif
+#endif
#ifndef DISABLE_OCSP
# include <gnutls/ocsp.h>
#endif
+#ifdef SUPPORT_DANE
+# include <gnutls/dane.h>
+#endif
+
+#include "tls-cipher-stdname.c"
+
+
+#ifdef MACRO_PREDEF
+void
+options_tls(void)
+{
+# ifdef EXPERIMENTAL_TLS_RESUME
+builtin_macro_create_var(US"_RESUME_DECODE", RESUME_DECODE_STRING );
+# endif
+}
+#else
+
/* GnuTLS 2 vs 3
/* Values for verify_requirement */
enum peer_verify_requirement
- { VERIFY_NONE, VERIFY_OPTIONAL, VERIFY_REQUIRED };
+ { VERIFY_NONE, VERIFY_OPTIONAL, VERIFY_REQUIRED, VERIFY_DANE };
/* This holds most state for server or client; with this, we can set up an
outbound TLS-enabled connection in an ACL callout, while not stomping all
int fd_in;
int fd_out;
BOOL peer_cert_verified;
+ BOOL peer_dane_verified;
BOOL trigger_sni_changes;
BOOL have_set_peerdn;
- const struct host_item *host;
- gnutls_x509_crt_t peercert;
+ const struct host_item *host; /* NULL if server */
+ gnutls_x509_crt_t peercert;
uschar *peerdn;
uschar *ciphersuite;
uschar *received_sni;
uschar *exp_tls_verify_certificates;
uschar *exp_tls_crl;
uschar *exp_tls_require_ciphers;
- uschar *exp_tls_ocsp_file;
const uschar *exp_tls_verify_cert_hostnames;
#ifndef DISABLE_EVENT
uschar *event_action;
#endif
+#ifdef SUPPORT_DANE
+ char * const * dane_data;
+ const int * dane_data_len;
+#endif
tls_support *tlsp; /* set in tls_init() */
uschar *xfer_buffer;
int xfer_buffer_lwm;
int xfer_buffer_hwm;
- int xfer_eof;
- int xfer_error;
+ BOOL xfer_eof; /*XXX never gets set! */
+ BOOL xfer_error;
} exim_gnutls_state_st;
static const exim_gnutls_state_st exim_gnutls_state_init = {
- .session = NULL,
- .x509_cred = NULL,
- .priority_cache = NULL,
- .verify_requirement = VERIFY_NONE,
+ /* all elements not explicitly intialised here get 0/NULL/FALSE */
.fd_in = -1,
.fd_out = -1,
- .peer_cert_verified = FALSE,
- .trigger_sni_changes =FALSE,
- .have_set_peerdn = FALSE,
- .host = NULL,
- .peercert = NULL,
- .peerdn = NULL,
- .ciphersuite = NULL,
- .received_sni = NULL,
-
- .tls_certificate = NULL,
- .tls_privatekey = NULL,
- .tls_sni = NULL,
- .tls_verify_certificates = NULL,
- .tls_crl = NULL,
- .tls_require_ciphers =NULL,
-
- .exp_tls_certificate = NULL,
- .exp_tls_privatekey = NULL,
- .exp_tls_verify_certificates = NULL,
- .exp_tls_crl = NULL,
- .exp_tls_require_ciphers = NULL,
- .exp_tls_ocsp_file = NULL,
- .exp_tls_verify_cert_hostnames = NULL,
-#ifndef DISABLE_EVENT
- .event_action = NULL,
-#endif
- .tlsp = NULL,
-
- .xfer_buffer = NULL,
- .xfer_buffer_lwm = 0,
- .xfer_buffer_hwm = 0,
- .xfer_eof = 0,
- .xfer_error = 0,
};
/* Not only do we have our own APIs which don't pass around state, assuming
XXX But see gnutls_session_get_ptr()
*/
-static exim_gnutls_state_st state_server, state_client;
+static exim_gnutls_state_st state_server;
/* dh_params are initialised once within the lifetime of a process using TLS;
if we used TLS in a long-lived daemon, we'd have to reconsider this. But we
static gnutls_dh_params_t dh_server_params = NULL;
-/* No idea how this value was chosen; preserving it. Default is 3600. */
-
-static const int ssl_session_timeout = 200;
+static int ssl_session_timeout = 7200; /* Two hours */
-static const char * const exim_default_gnutls_priority = "NORMAL";
+static const uschar * const exim_default_gnutls_priority = US"NORMAL";
/* Guard library core initialisation */
#ifndef DISABLE_OCSP
static BOOL gnutls_buggy_ocsp = FALSE;
+static BOOL exim_testharness_disable_ocsp_validity_check = FALSE;
#endif
+#ifdef EXPERIMENTAL_TLS_RESUME
+static gnutls_datum_t server_sessticket_key;
+#endif
/* ------------------------------------------------------------------------ */
/* macros */
/* Set this to control gnutls_global_set_log_level(); values 0 to 9 will setup
the library logging; a value less than 0 disables the calls to set up logging
-callbacks. */
+callbacks. GNuTLS also looks for an environment variable - except not for
+setuid binaries, making it useless - "GNUTLS_DEBUG_LEVEL".
+Allegedly the testscript line "GNUTLS_DEBUG_LEVEL=9 sudo exim ..." would work,
+but the env var must be added to /etc/sudoers too. */
#ifndef EXIM_GNUTLS_LIBRARY_LOG_LEVEL
# define EXIM_GNUTLS_LIBRARY_LOG_LEVEL -1
#endif
# define EXIM_SERVER_DH_BITS_PRE2_12 1024
#endif
-#define exim_gnutls_err_check(Label) do { \
- if (rc != GNUTLS_E_SUCCESS) \
- return tls_error((Label), gnutls_strerror(rc), host, errstr); \
- } while (0)
-
#define expand_check_tlsvar(Varname, errstr) \
expand_check(state->Varname, US #Varname, &state->exp_##Varname, errstr)
static int exim_sni_handling_cb(gnutls_session_t session);
-#ifndef DISABLE_OCSP
+#if !defined(DISABLE_OCSP)
static int server_ocsp_stapling_cb(gnutls_session_t session, void * ptr,
gnutls_datum_t * ocsp_response);
#endif
+#ifdef EXPERIMENTAL_TLS_RESUME
+static int
+tls_server_ticket_cb(gnutls_session_t sess, u_int htype, unsigned when,
+ unsigned incoming, const gnutls_datum_t * msg);
+#endif
+/* Daemon one-time initialisation */
+void
+tls_daemon_init(void)
+{
+#ifdef EXPERIMENTAL_TLS_RESUME
+/* We are dependent on the GnuTLS implementation of the Session Ticket
+encryption; both the strength and the key rotation period. We hope that
+the strength at least matches that of the ciphersuite (but GnuTLS does not
+document this). */
+
+static BOOL once = FALSE;
+if (once) return;
+once = TRUE;
+gnutls_session_ticket_key_generate(&server_sessticket_key); /* >= 2.10.0 */
+if (f.running_in_test_harness) ssl_session_timeout = 6;
+#endif
+}
+
/* ------------------------------------------------------------------------ */
/* Static functions */
*/
static int
-tls_error(const uschar *prefix, const char *msg, const host_item *host,
+tls_error(const uschar *prefix, const uschar *msg, const host_item *host,
uschar ** errstr)
{
if (errstr)
- *errstr = string_sprintf("(%s)%s%s", prefix, msg ? ": " : "", msg ? msg : "");
+ *errstr = string_sprintf("(%s)%s%s", prefix, msg ? ": " : "", msg ? msg : US"");
return host ? FAIL : DEFER;
}
+static int
+tls_error_gnu(const uschar *prefix, int err, const host_item *host,
+ uschar ** errstr)
+{
+return tls_error(prefix, US gnutls_strerror(err), host, errstr);
+}
+
+static int
+tls_error_sys(const uschar *prefix, int err, const host_item *host,
+ uschar ** errstr)
+{
+return tls_error(prefix, US strerror(err), host, errstr);
+}
/*************************************************
state the current GnuTLS exim state container
rc the GnuTLS error code, or 0 if it's a local error
when text identifying read or write
- text local error text when ec is 0
+ text local error text when rc is 0
Returns: nothing
*/
static void
record_io_error(exim_gnutls_state_st *state, int rc, uschar *when, uschar *text)
{
-const char * msg;
+const uschar * msg;
uschar * errstr;
if (rc == GNUTLS_E_FATAL_ALERT_RECEIVED)
- msg = CS string_sprintf("%s: %s", US gnutls_strerror(rc),
+ msg = string_sprintf("A TLS fatal alert has been received: %s",
US gnutls_alert_get_name(gnutls_alert_get(state->session)));
else
- msg = gnutls_strerror(rc);
+ msg = US gnutls_strerror(rc);
(void) tls_error(when, msg, state->host, &errstr);
static void
extract_exim_vars_from_tls_state(exim_gnutls_state_st * state)
{
-gnutls_cipher_algorithm_t cipher;
#ifdef HAVE_GNUTLS_SESSION_CHANNEL_BINDING
int old_pool;
int rc;
#endif
tls_support * tlsp = state->tlsp;
-tlsp->active = state->fd_out;
-
-cipher = gnutls_cipher_get(state->session);
-/* returns size in "bytes" */
-tlsp->bits = gnutls_cipher_get_key_size(cipher) * 8;
-
-tlsp->cipher = state->ciphersuite;
+tlsp->active.sock = state->fd_out;
+tlsp->active.tls_ctx = state;
DEBUG(D_tls) debug_printf("cipher: %s\n", state->ciphersuite);
tlsp->certificate_verified = state->peer_cert_verified;
+#ifdef SUPPORT_DANE
+tlsp->dane_verified = state->peer_dane_verified;
+#endif
/* note that tls_channelbinding_b64 is not saved to the spool file, since it's
only available for use for authenticators while this TLS session is running. */
#ifdef HAVE_GNUTLS_SESSION_CHANNEL_BINDING
channel.data = NULL;
channel.size = 0;
-rc = gnutls_session_channel_binding(state->session, GNUTLS_CB_TLS_UNIQUE, &channel);
-if (rc) {
- DEBUG(D_tls) debug_printf("Channel binding error: %s\n", gnutls_strerror(rc));
-} else {
+if ((rc = gnutls_session_channel_binding(state->session, GNUTLS_CB_TLS_UNIQUE, &channel)))
+ { DEBUG(D_tls) debug_printf("Channel binding error: %s\n", gnutls_strerror(rc)); }
+else
+ {
old_pool = store_pool;
store_pool = POOL_PERM;
- tls_channelbinding_b64 = b64encode(channel.data, (int)channel.size);
+ tls_channelbinding_b64 = b64encode(CUS channel.data, (int)channel.size);
store_pool = old_pool;
DEBUG(D_tls) debug_printf("Have channel bindings cached for possible auth usage.\n");
-}
+ }
#endif
/* peercert is set in peer_status() */
size_t sz;
uschar *exp_tls_dhparam;
BOOL use_file_in_spool = FALSE;
-BOOL use_fixed_file = FALSE;
host_item *host = NULL; /* dummy for macros */
DEBUG(D_tls) debug_printf("Initialising GnuTLS server params.\n");
-rc = gnutls_dh_params_init(&dh_server_params);
-exim_gnutls_err_check(US"gnutls_dh_params_init");
+if ((rc = gnutls_dh_params_init(&dh_server_params)))
+ return tls_error_gnu(US"gnutls_dh_params_init", rc, host, errstr);
m.data = NULL;
m.size = 0;
else if (exp_tls_dhparam[0] != '/')
{
if (!(m.data = US std_dh_prime_named(exp_tls_dhparam)))
- return tls_error(US"No standard prime named", CS exp_tls_dhparam, NULL, errstr);
+ return tls_error(US"No standard prime named", exp_tls_dhparam, NULL, errstr);
m.size = Ustrlen(m.data);
}
else
- {
- use_fixed_file = TRUE;
filename = exp_tls_dhparam;
- }
if (m.data)
{
- rc = gnutls_dh_params_import_pkcs3(dh_server_params, &m, GNUTLS_X509_FMT_PEM);
- exim_gnutls_err_check(US"gnutls_dh_params_import_pkcs3");
+ if ((rc = gnutls_dh_params_import_pkcs3(dh_server_params, &m, GNUTLS_X509_FMT_PEM)))
+ return tls_error_gnu(US"gnutls_dh_params_import_pkcs3", rc, host, errstr);
DEBUG(D_tls) debug_printf("Loaded fixed standard D-H parameters\n");
return OK;
}
#ifdef HAVE_GNUTLS_SEC_PARAM_CONSTANTS
/* If you change this constant, also change dh_param_fn_ext so that we can use a
different filename and ensure we have sufficient bits. */
-dh_bits = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, GNUTLS_SEC_PARAM_NORMAL);
-if (!dh_bits)
+
+if (!(dh_bits = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, GNUTLS_SEC_PARAM_NORMAL)))
return tls_error(US"gnutls_sec_param_to_pk_bits() failed", NULL, NULL, errstr);
DEBUG(D_tls)
debug_printf("GnuTLS tells us that for D-H PK, NORMAL is %d bits.\n",
{
saved_errno = errno;
(void)close(fd);
- return tls_error(US"TLS cache stat failed", strerror(saved_errno), NULL, errstr);
+ return tls_error_sys(US"TLS cache stat failed", saved_errno, NULL, errstr);
}
if (!S_ISREG(statbuf.st_mode))
{
{
saved_errno = errno;
(void)close(fd);
- return tls_error(US"fdopen(TLS cache stat fd) failed",
- strerror(saved_errno), NULL, errstr);
+ return tls_error_sys(US"fdopen(TLS cache stat fd) failed",
+ saved_errno, NULL, errstr);
}
m.size = statbuf.st_size;
- if (!(m.data = malloc(m.size)))
+ if (!(m.data = store_malloc(m.size)))
{
fclose(fp);
- return tls_error(US"malloc failed", strerror(errno), NULL, errstr);
+ return tls_error_sys(US"malloc failed", errno, NULL, errstr);
}
if (!(sz = fread(m.data, m.size, 1, fp)))
{
saved_errno = errno;
fclose(fp);
- free(m.data);
- return tls_error(US"fread failed", strerror(saved_errno), NULL, errstr);
+ store_free(m.data);
+ return tls_error_sys(US"fread failed", saved_errno, NULL, errstr);
}
fclose(fp);
rc = gnutls_dh_params_import_pkcs3(dh_server_params, &m, GNUTLS_X509_FMT_PEM);
- free(m.data);
- exim_gnutls_err_check(US"gnutls_dh_params_import_pkcs3");
+ store_free(m.data);
+ if (rc)
+ return tls_error_gnu(US"gnutls_dh_params_import_pkcs3", rc, host, errstr);
DEBUG(D_tls) debug_printf("read D-H parameters from file \"%s\"\n", filename);
}
if ((PATH_MAX - Ustrlen(filename)) < 10)
return tls_error(US"Filename too long to generate replacement",
- CS filename, NULL, errstr);
+ filename, NULL, errstr);
- temp_fn = string_copy(US "%s.XXXXXXX");
+ temp_fn = string_copy(US"%s.XXXXXXX");
if ((fd = mkstemp(CS temp_fn)) < 0) /* modifies temp_fn */
- return tls_error(US"Unable to open temp file", strerror(errno), NULL, errstr);
- (void)fchown(fd, exim_uid, exim_gid); /* Probably not necessary */
+ return tls_error_sys(US"Unable to open temp file", errno, NULL, errstr);
+ (void)exim_chown(temp_fn, exim_uid, exim_gid); /* Probably not necessary */
/* GnuTLS overshoots!
* If we ask for 2236, we might get 2237 or more.
DEBUG(D_tls)
debug_printf("requesting generation of %d bit Diffie-Hellman prime ...\n",
dh_bits_gen);
- rc = gnutls_dh_params_generate2(dh_server_params, dh_bits_gen);
- exim_gnutls_err_check(US"gnutls_dh_params_generate2");
+ if ((rc = gnutls_dh_params_generate2(dh_server_params, dh_bits_gen)))
+ return tls_error_gnu(US"gnutls_dh_params_generate2", rc, host, errstr);
/* gnutls_dh_params_export_pkcs3() will tell us the exact size, every time,
and I confirmed that a NULL call to get the size first is how the GnuTLS
sz = 0;
m.data = NULL;
- rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM,
- m.data, &sz);
- if (rc != GNUTLS_E_SHORT_MEMORY_BUFFER)
- exim_gnutls_err_check(US"gnutls_dh_params_export_pkcs3(NULL) sizing");
+ if ( (rc = gnutls_dh_params_export_pkcs3(dh_server_params,
+ GNUTLS_X509_FMT_PEM, m.data, &sz))
+ && rc != GNUTLS_E_SHORT_MEMORY_BUFFER)
+ return tls_error_gnu(US"gnutls_dh_params_export_pkcs3(NULL) sizing",
+ rc, host, errstr);
m.size = sz;
- if (!(m.data = malloc(m.size)))
- return tls_error(US"memory allocation failed", strerror(errno), NULL, errstr);
+ if (!(m.data = store_malloc(m.size)))
+ return tls_error_sys(US"memory allocation failed", errno, NULL, errstr);
/* this will return a size 1 less than the allocation size above */
- rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM,
- m.data, &sz);
- if (rc != GNUTLS_E_SUCCESS)
+ if ((rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM,
+ m.data, &sz)))
{
- free(m.data);
- exim_gnutls_err_check(US"gnutls_dh_params_export_pkcs3() real");
+ store_free(m.data);
+ return tls_error_gnu(US"gnutls_dh_params_export_pkcs3() real", rc, host, errstr);
}
m.size = sz; /* shrink by 1, probably */
if ((sz = write_to_fd_buf(fd, m.data, (size_t) m.size)) != m.size)
{
- free(m.data);
- return tls_error(US"TLS cache write D-H params failed",
- strerror(errno), NULL, errstr);
+ store_free(m.data);
+ return tls_error_sys(US"TLS cache write D-H params failed",
+ errno, NULL, errstr);
}
- free(m.data);
+ store_free(m.data);
if ((sz = write_to_fd_buf(fd, US"\n", 1)) != 1)
- return tls_error(US"TLS cache write D-H params final newline failed",
- strerror(errno), NULL, errstr);
+ return tls_error_sys(US"TLS cache write D-H params final newline failed",
+ errno, NULL, errstr);
if ((rc = close(fd)))
- return tls_error(US"TLS cache write close() failed", strerror(errno), NULL, errstr);
+ return tls_error_sys(US"TLS cache write close() failed", errno, NULL, errstr);
if (Urename(temp_fn, filename) < 0)
- return tls_error(string_sprintf("failed to rename \"%s\" as \"%s\"",
- temp_fn, filename), strerror(errno), NULL, errstr);
+ return tls_error_sys(string_sprintf("failed to rename \"%s\" as \"%s\"",
+ temp_fn, filename), errno, NULL, errstr);
DEBUG(D_tls) debug_printf("wrote D-H parameters to file \"%s\"\n", filename);
}
where = US"generating pkey";
if ((rc = gnutls_x509_privkey_generate(pkey, GNUTLS_PK_RSA,
#ifdef SUPPORT_PARAM_TO_PK_BITS
- gnutls_sec_param_to_pk_bits(GNUTLS_PK_RSA, GNUTLS_SEC_PARAM_LOW),
+# ifndef GNUTLS_SEC_PARAM_MEDIUM
+# define GNUTLS_SEC_PARAM_MEDIUM GNUTLS_SEC_PARAM_HIGH
+# endif
+ gnutls_sec_param_to_pk_bits(GNUTLS_PK_RSA, GNUTLS_SEC_PARAM_MEDIUM),
#else
- 1024,
+ 2048,
#endif
0)))
goto err;
where = US"configuring cert";
-now = 0;
+now = 1;
if ( (rc = gnutls_x509_crt_set_version(cert, 3))
|| (rc = gnutls_x509_crt_set_serial(cert, &now, sizeof(now)))
|| (rc = gnutls_x509_crt_set_activation_time(cert, now = time(NULL)))
return rc;
err:
- rc = tls_error(where, gnutls_strerror(rc), NULL, errstr);
+ rc = tls_error_gnu(where, rc, NULL, errstr);
goto out;
}
+/* Add certificate and key, from files.
+
+Return:
+ Zero or negative: good. Negate value for certificate index if < 0.
+ Greater than zero: FAIL or DEFER code.
+*/
+
static int
tls_add_certfile(exim_gnutls_state_st * state, const host_item * host,
uschar * certfile, uschar * keyfile, uschar ** errstr)
{
+/*XXX returns certs index for gnutls_certificate_set_x509_key_file(),
+given suitable flags set */
+
int rc = gnutls_certificate_set_x509_key_file(state->x509_cred,
CS certfile, CS keyfile, GNUTLS_X509_FMT_PEM);
-exim_gnutls_err_check(
- string_sprintf("cert/key setup: cert=%s key=%s", certfile, keyfile));
-return OK;
+if (rc < 0)
+ return tls_error_gnu(
+ string_sprintf("cert/key setup: cert=%s key=%s", certfile, keyfile),
+ rc, host, errstr);
+return -rc;
+}
+
+
+/* Make a note that we saw a status-request */
+static int
+tls_server_clienthello_ext(void * ctx, unsigned tls_id,
+ const unsigned char *data, unsigned size)
+{
+/* https://www.iana.org/assignments/tls-extensiontype-values/tls-extensiontype-values.xhtml */
+if (tls_id == 5) /* status_request */
+ {
+ DEBUG(D_tls) debug_printf("Seen status_request extension\n");
+ tls_in.ocsp = OCSP_NOT_RESP;
+ }
+return 0;
+}
+
+/* Callback for client-hello, on server, if we think we might serve stapled-OCSP */
+static int
+tls_server_clienthello_cb(gnutls_session_t session, unsigned int htype,
+ unsigned when, unsigned int incoming, const gnutls_datum_t * msg)
+{
+/* Call fn for each extension seen. 3.6.3 onwards */
+return gnutls_ext_raw_parse(NULL, tls_server_clienthello_ext, msg,
+ GNUTLS_EXT_RAW_FLAG_TLS_CLIENT_HELLO);
+}
+
+/* Callback for certificate-status, on server. We sent stapled OCSP. */
+static int
+tls_server_certstatus_cb(gnutls_session_t session, unsigned int htype,
+ unsigned when, unsigned int incoming, const gnutls_datum_t * msg)
+{
+DEBUG(D_tls) debug_printf("Sending certificate-status\n");
+#ifdef SUPPORT_SRV_OCSP_STACK
+tls_in.ocsp = exim_testharness_disable_ocsp_validity_check
+ ? OCSP_VFY_NOT_TRIED : OCSP_VFIED; /* We know that GnuTLS verifies responses */
+#else
+tls_in.ocsp = OCSP_VFY_NOT_TRIED;
+#endif
+return 0;
+}
+
+/* Callback for handshake messages, on server */
+static int
+tls_server_hook_cb(gnutls_session_t sess, u_int htype, unsigned when,
+ unsigned incoming, const gnutls_datum_t * msg)
+{
+switch (htype)
+ {
+ case GNUTLS_HANDSHAKE_CLIENT_HELLO:
+ return tls_server_clienthello_cb(sess, htype, when, incoming, msg);
+ case GNUTLS_HANDSHAKE_CERTIFICATE_STATUS:
+ return tls_server_certstatus_cb(sess, htype, when, incoming, msg);
+#ifdef EXPERIMENTAL_TLS_RESUME
+ case GNUTLS_HANDSHAKE_NEW_SESSION_TICKET:
+ return tls_server_ticket_cb(sess, htype, when, incoming, msg);
+#endif
+ default:
+ return 0;
+ }
}
+static void
+tls_server_testharness_ocsp_fiddle(void)
+{
+extern char ** environ;
+if (environ) for (uschar ** p = USS environ; *p; p++)
+ if (Ustrncmp(*p, "EXIM_TESTHARNESS_DISABLE_OCSPVALIDITYCHECK", 42) == 0)
+ {
+ DEBUG(D_tls) debug_printf("Permitting known bad OCSP response\n");
+ exim_testharness_disable_ocsp_validity_check = TRUE;
+ }
+}
+
/*************************************************
* Variables re-expanded post-SNI *
*************************************************/
saved_tls_crl = state->exp_tls_crl;
}
-rc = gnutls_certificate_allocate_credentials(&state->x509_cred);
-exim_gnutls_err_check(US"gnutls_certificate_allocate_credentials");
+if ((rc = gnutls_certificate_allocate_credentials(&state->x509_cred)))
+ return tls_error_gnu(US"gnutls_certificate_allocate_credentials",
+ rc, host, errstr);
+
+#ifdef SUPPORT_SRV_OCSP_STACK
+gnutls_certificate_set_flags(state->x509_cred, GNUTLS_CERTIFICATE_API_V2);
+#endif
/* remember: expand_check_tlsvar() is expand_check() but fiddling with
state members, assuming consistent naming; and expand_check() returns
{
const uschar * clist = state->exp_tls_certificate;
const uschar * klist = state->exp_tls_privatekey;
- int csep = 0, ksep = 0;
- uschar * cfile, * kfile;
+ const uschar * olist;
+ int csep = 0, ksep = 0, osep = 0, cnt = 0;
+ uschar * cfile, * kfile, * ofile;
+
+#ifndef DISABLE_OCSP
+ if (!expand_check(tls_ocsp_file, US"tls_ocsp_file", &ofile, errstr))
+ return DEFER;
+ olist = ofile;
+#endif
while (cfile = string_nextinlist(&clist, &csep, NULL, 0))
+
if (!(kfile = string_nextinlist(&klist, &ksep, NULL, 0)))
return tls_error(US"cert/key setup: out of keys", NULL, host, errstr);
- else if ((rc = tls_add_certfile(state, host, cfile, kfile, errstr)))
+ else if (0 < (rc = tls_add_certfile(state, host, cfile, kfile, errstr)))
return rc;
else
- DEBUG(D_tls) debug_printf("TLS: cert/key %s registered\n", cfile);
+ {
+ int gnutls_cert_index = -rc;
+ DEBUG(D_tls) debug_printf("TLS: cert/key %d %s registered\n", gnutls_cert_index, cfile);
+
+ /* Set the OCSP stapling server info */
+
+#ifndef DISABLE_OCSP
+ if (tls_ocsp_file)
+ {
+ if (gnutls_buggy_ocsp)
+ {
+ DEBUG(D_tls)
+ debug_printf("GnuTLS library is buggy for OCSP; avoiding\n");
+ }
+ else if ((ofile = string_nextinlist(&olist, &osep, NULL, 0)))
+ {
+ DEBUG(D_tls) debug_printf("OCSP response file = %s\n", ofile);
+
+# ifdef SUPPORT_SRV_OCSP_STACK
+ if (f.running_in_test_harness) tls_server_testharness_ocsp_fiddle();
+
+ if (!exim_testharness_disable_ocsp_validity_check)
+ {
+ if ((rc = gnutls_certificate_set_ocsp_status_request_file2(
+ state->x509_cred, CCS ofile, gnutls_cert_index,
+ GNUTLS_X509_FMT_DER)) < 0)
+ return tls_error_gnu(
+ US"gnutls_certificate_set_ocsp_status_request_file2",
+ rc, host, errstr);
+
+ /* Arrange callbacks for OCSP request observability */
+
+ gnutls_handshake_set_hook_function(state->session,
+ GNUTLS_HANDSHAKE_ANY, GNUTLS_HOOK_POST, tls_server_hook_cb);
+ }
+ else
+# endif
+ {
+ if (cnt++ > 0)
+ {
+ DEBUG(D_tls)
+ debug_printf("oops; multiple OCSP files not supported\n");
+ break;
+ }
+ gnutls_certificate_set_ocsp_status_request_function(
+ state->x509_cred, server_ocsp_stapling_cb, ofile);
+ }
+ }
+ else
+ DEBUG(D_tls) debug_printf("ran out of OCSP response files in list\n");
+#endif
+ }
+ }
}
- else
+ else /* client */
{
- if ((rc = tls_add_certfile(state, host,
+ if (0 < (rc = tls_add_certfile(state, host,
state->exp_tls_certificate, state->exp_tls_privatekey, errstr)))
return rc;
DEBUG(D_tls) debug_printf("TLS: cert/key registered\n");
} /* tls_certificate */
-/* Set the OCSP stapling server info */
-
-#ifndef DISABLE_OCSP
-if ( !host /* server */
- && tls_ocsp_file
- )
- {
- if (gnutls_buggy_ocsp)
- {
- DEBUG(D_tls) debug_printf("GnuTLS library is buggy for OCSP; avoiding\n");
- }
- else
- {
- if (!expand_check(tls_ocsp_file, US"tls_ocsp_file",
- &state->exp_tls_ocsp_file, errstr))
- return DEFER;
-
- /* Use the full callback method for stapling just to get observability.
- More efficient would be to read the file once only, if it never changed
- (due to SNI). Would need restart on file update, or watch datestamp. */
-
- gnutls_certificate_set_ocsp_status_request_function(state->x509_cred,
- server_ocsp_stapling_cb, state->exp_tls_ocsp_file);
-
- DEBUG(D_tls) debug_printf("OCSP response file = %s\n", state->exp_tls_ocsp_file);
- }
- }
-#endif
-
-
/* Set the trusted CAs file if one is provided, and then add the CRL if one is
provided. Experiment shows that, if the certificate file is empty, an unhelpful
error message is provided. However, if we just refrain from setting anything up
#endif
gnutls_certificate_set_x509_trust_file(state->x509_cred,
CS state->exp_tls_verify_certificates, GNUTLS_X509_FMT_PEM);
+
+#ifdef SUPPORT_CA_DIR
+ /* Mimic the behaviour with OpenSSL of not advertising a usable-cert list
+ when using the directory-of-certs config model. */
+
+ if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
+ gnutls_certificate_send_x509_rdn_sequence(state->session, 1);
+#endif
}
if (cert_count < 0)
- {
- rc = cert_count;
- exim_gnutls_err_check(US"setting certificate trust");
- }
-DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n", cert_count);
+ return tls_error_gnu(US"setting certificate trust", cert_count, host, errstr);
+DEBUG(D_tls)
+ debug_printf("Added %d certificate authorities.\n", cert_count);
if (state->tls_crl && *state->tls_crl &&
state->exp_tls_crl && *state->exp_tls_crl)
{
DEBUG(D_tls) debug_printf("loading CRL file = %s\n", state->exp_tls_crl);
- cert_count = gnutls_certificate_set_x509_crl_file(state->x509_cred,
- CS state->exp_tls_crl, GNUTLS_X509_FMT_PEM);
- if (cert_count < 0)
- {
- rc = cert_count;
- exim_gnutls_err_check(US"gnutls_certificate_set_x509_crl_file");
- }
+ if ((cert_count = gnutls_certificate_set_x509_crl_file(state->x509_cred,
+ CS state->exp_tls_crl, GNUTLS_X509_FMT_PEM)) < 0)
+ return tls_error_gnu(US"gnutls_certificate_set_x509_crl_file",
+ cert_count, host, errstr);
+
DEBUG(D_tls) debug_printf("Processed %d CRLs.\n", cert_count);
}
if (!state->host)
{
if (!dh_server_params)
- {
- rc = init_server_dh(errstr);
- if (rc != OK) return rc;
- }
+ if ((rc = init_server_dh(errstr)) != OK) return rc;
gnutls_certificate_set_dh_params(state->x509_cred, dh_server_params);
}
/* Link the credentials to the session. */
-rc = gnutls_credentials_set(state->session, GNUTLS_CRD_CERTIFICATE, state->x509_cred);
-exim_gnutls_err_check(US"gnutls_credentials_set");
+if ((rc = gnutls_credentials_set(state->session,
+ GNUTLS_CRD_CERTIFICATE, state->x509_cred)))
+ return tls_error_gnu(US"gnutls_credentials_set", rc, host, errstr);
return OK;
}
const uschar *crl,
const uschar *require_ciphers,
exim_gnutls_state_st **caller_state,
+ tls_support * tlsp,
uschar ** errstr)
{
-exim_gnutls_state_st *state;
+exim_gnutls_state_st * state;
int rc;
size_t sz;
-const char *errpos;
-uschar *p;
-BOOL want_default_priorities;
+const char * errpos;
+const uschar * p;
if (!exim_gnutls_base_init_done)
{
environment variables are used and so breaks for users calling mailq.
To prevent this, we init PKCS11 first, which is the documented approach. */
if (!gnutls_allow_auto_pkcs11)
- {
- rc = gnutls_pkcs11_init(GNUTLS_PKCS11_FLAG_MANUAL, NULL);
- exim_gnutls_err_check(US"gnutls_pkcs11_init");
- }
+ if ((rc = gnutls_pkcs11_init(GNUTLS_PKCS11_FLAG_MANUAL, NULL)))
+ return tls_error_gnu(US"gnutls_pkcs11_init", rc, host, errstr);
#endif
- rc = gnutls_global_init();
- exim_gnutls_err_check(US"gnutls_global_init");
+ if ((rc = gnutls_global_init()))
+ return tls_error_gnu(US"gnutls_global_init", rc, host, errstr);
#if EXIM_GNUTLS_LIBRARY_LOG_LEVEL >= 0
DEBUG(D_tls)
{
gnutls_global_set_log_function(exim_gnutls_logger_cb);
- /* arbitrarily chosen level; bump upto 9 for more */
+ /* arbitrarily chosen level; bump up to 9 for more */
gnutls_global_set_log_level(EXIM_GNUTLS_LIBRARY_LOG_LEVEL);
}
#endif
if (host)
{
- state = &state_client;
+ /* For client-side sessions we allocate a context. This lets us run
+ several in parallel. */
+ int old_pool = store_pool;
+ store_pool = POOL_PERM;
+ state = store_get(sizeof(exim_gnutls_state_st), FALSE);
+ store_pool = old_pool;
+
memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));
- state->tlsp = &tls_out;
+ state->tlsp = tlsp;
DEBUG(D_tls) debug_printf("initialising GnuTLS client session\n");
rc = gnutls_init(&state->session, GNUTLS_CLIENT);
}
{
state = &state_server;
memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));
- state->tlsp = &tls_in;
+ state->tlsp = tlsp;
DEBUG(D_tls) debug_printf("initialising GnuTLS server session\n");
rc = gnutls_init(&state->session, GNUTLS_SERVER);
}
-exim_gnutls_err_check(US"gnutls_init");
+if (rc)
+ return tls_error_gnu(US"gnutls_init", rc, host, errstr);
state->host = host;
DEBUG(D_tls)
debug_printf("Setting TLS client SNI to \"%s\"\n", state->tlsp->sni);
sz = Ustrlen(state->tlsp->sni);
- rc = gnutls_server_name_set(state->session,
- GNUTLS_NAME_DNS, state->tlsp->sni, sz);
- exim_gnutls_err_check(US"gnutls_server_name_set");
+ if ((rc = gnutls_server_name_set(state->session,
+ GNUTLS_NAME_DNS, state->tlsp->sni, sz)))
+ return tls_error_gnu(US"gnutls_server_name_set", rc, host, errstr);
}
}
else if (state->tls_sni)
This was backwards incompatible, but means Exim no longer needs to track
all algorithms and provide string forms for them. */
-want_default_priorities = TRUE;
-
+p = NULL;
if (state->tls_require_ciphers && *state->tls_require_ciphers)
{
if (!expand_check_tlsvar(tls_require_ciphers, errstr))
return DEFER;
if (state->exp_tls_require_ciphers && *state->exp_tls_require_ciphers)
{
- DEBUG(D_tls) debug_printf("GnuTLS session cipher/priority \"%s\"\n",
- state->exp_tls_require_ciphers);
-
- rc = gnutls_priority_init(&state->priority_cache,
- CS state->exp_tls_require_ciphers, &errpos);
- want_default_priorities = FALSE;
p = state->exp_tls_require_ciphers;
+ DEBUG(D_tls) debug_printf("GnuTLS session cipher/priority \"%s\"\n", p);
}
}
-if (want_default_priorities)
+if (!p)
{
+ p = exim_default_gnutls_priority;
DEBUG(D_tls)
- debug_printf("GnuTLS using default session cipher/priority \"%s\"\n",
- exim_default_gnutls_priority);
- rc = gnutls_priority_init(&state->priority_cache,
- exim_default_gnutls_priority, &errpos);
- p = US exim_default_gnutls_priority;
+ debug_printf("GnuTLS using default session cipher/priority \"%s\"\n", p);
}
-exim_gnutls_err_check(string_sprintf(
- "gnutls_priority_init(%s) failed at offset %ld, \"%.6s..\"",
- p, errpos - CS p, errpos));
+if ((rc = gnutls_priority_init(&state->priority_cache, CCS p, &errpos)))
+ return tls_error_gnu(string_sprintf(
+ "gnutls_priority_init(%s) failed at offset %ld, \"%.6s..\"",
+ p, errpos - CS p, errpos),
+ rc, host, errstr);
+
+if ((rc = gnutls_priority_set(state->session, state->priority_cache)))
+ return tls_error_gnu(US"gnutls_priority_set", rc, host, errstr);
-rc = gnutls_priority_set(state->session, state->priority_cache);
-exim_gnutls_err_check(US"gnutls_priority_set");
+/* This also sets the server ticket expiration time to the same, and
+the STEK rotation time to 3x. */
gnutls_db_set_cache_expiration(state->session, ssl_session_timeout);
* Extract peer information *
*************************************************/
+static const uschar *
+cipher_stdname_kcm(gnutls_kx_algorithm_t kx, gnutls_cipher_algorithm_t cipher,
+ gnutls_mac_algorithm_t mac)
+{
+uschar cs_id[2];
+gnutls_kx_algorithm_t kx_i;
+gnutls_cipher_algorithm_t cipher_i;
+gnutls_mac_algorithm_t mac_i;
+
+for (size_t i = 0;
+ gnutls_cipher_suite_info(i, cs_id, &kx_i, &cipher_i, &mac_i, NULL);
+ i++)
+ if (kx_i == kx && cipher_i == cipher && mac_i == mac)
+ return cipher_stdname(cs_id[0], cs_id[1]);
+return NULL;
+}
+
+
+
/* Called from both server and client code.
Only this is allowed to set state->peerdn and state->have_set_peerdn
and we use that to detect double-calls.
*/
static int
-peer_status(exim_gnutls_state_st *state, uschar ** errstr)
+peer_status(exim_gnutls_state_st * state, uschar ** errstr)
{
-uschar cipherbuf[256];
-const gnutls_datum_t *cert_list;
+gnutls_session_t session = state->session;
+const gnutls_datum_t * cert_list;
int old_pool, rc;
unsigned int cert_list_size = 0;
gnutls_protocol_t protocol;
gnutls_mac_algorithm_t mac;
gnutls_certificate_type_t ct;
gnutls_x509_crt_t crt;
-uschar *p, *dn_buf;
+uschar * dn_buf;
size_t sz;
if (state->have_set_peerdn)
state->peerdn = NULL;
/* tls_cipher */
-cipher = gnutls_cipher_get(state->session);
-protocol = gnutls_protocol_get_version(state->session);
-mac = gnutls_mac_get(state->session);
-kx = gnutls_kx_get(state->session);
-
-string_format(cipherbuf, sizeof(cipherbuf),
- "%s:%s:%d",
- gnutls_protocol_get_name(protocol),
- gnutls_cipher_suite_get_name(kx, cipher, mac),
- (int) gnutls_cipher_get_key_size(cipher) * 8);
-
-/* I don't see a way that spaces could occur, in the current GnuTLS
-code base, but it was a concern in the old code and perhaps older GnuTLS
-releases did return "TLS 1.0"; play it safe, just in case. */
-for (p = cipherbuf; *p != '\0'; ++p)
- if (isspace(*p))
- *p = '-';
+cipher = gnutls_cipher_get(session);
+protocol = gnutls_protocol_get_version(session);
+mac = gnutls_mac_get(session);
+kx =
+#ifdef GNUTLS_TLS1_3
+ protocol >= GNUTLS_TLS1_3 ? 0 :
+#endif
+ gnutls_kx_get(session);
+
old_pool = store_pool;
-store_pool = POOL_PERM;
-state->ciphersuite = string_copy(cipherbuf);
+ {
+ tls_support * tlsp = state->tlsp;
+ store_pool = POOL_PERM;
+
+#ifdef SUPPORT_GNUTLS_SESS_DESC
+ {
+ gstring * g = NULL;
+ uschar * s = US gnutls_session_get_desc(session), c;
+
+ /* Nikos M suggests we use this by preference. It returns like:
+ (TLS1.3)-(ECDHE-SECP256R1)-(RSA-PSS-RSAE-SHA256)-(AES-256-GCM)
+
+ For partial back-compat, put a colon after the TLS version, replace the
+ )-( grouping with __, replace in-group - with _ and append the :keysize. */
+
+ /* debug_printf("peer_status: gnutls_session_get_desc %s\n", s); */
+
+ for (s++; (c = *s) && c != ')'; s++) g = string_catn(g, s, 1);
+ g = string_catn(g, US":", 1);
+ if (*s) s++; /* now on _ between groups */
+ while ((c = *s))
+ {
+ for (*++s && ++s; (c = *s) && c != ')'; s++) g = string_catn(g, c == '-' ? US"_" : s, 1);
+ /* now on ) closing group */
+ if ((c = *s) && *++s == '-') g = string_catn(g, US"__", 2);
+ /* now on _ between groups */
+ }
+ g = string_catn(g, US":", 1);
+ g = string_cat(g, string_sprintf("%d", (int) gnutls_cipher_get_key_size(cipher) * 8));
+ state->ciphersuite = string_from_gstring(g);
+ }
+#else
+ state->ciphersuite = string_sprintf("%s:%s:%d",
+ gnutls_protocol_get_name(protocol),
+ gnutls_cipher_suite_get_name(kx, cipher, mac),
+ (int) gnutls_cipher_get_key_size(cipher) * 8);
+
+ /* I don't see a way that spaces could occur, in the current GnuTLS
+ code base, but it was a concern in the old code and perhaps older GnuTLS
+ releases did return "TLS 1.0"; play it safe, just in case. */
+
+ for (uschar * p = state->ciphersuite; *p; p++) if (isspace(*p)) *p = '-';
+#endif
+
+/* debug_printf("peer_status: ciphersuite %s\n", state->ciphersuite); */
+
+ tlsp->cipher = state->ciphersuite;
+ tlsp->bits = gnutls_cipher_get_key_size(cipher) * 8;
+
+ tlsp->cipher_stdname = cipher_stdname_kcm(kx, cipher, mac);
+ }
store_pool = old_pool;
-state->tlsp->cipher = state->ciphersuite;
/* tls_peerdn */
-cert_list = gnutls_certificate_get_peers(state->session, &cert_list_size);
+cert_list = gnutls_certificate_get_peers(session, &cert_list_size);
-if (cert_list == NULL || cert_list_size == 0)
+if (!cert_list || cert_list_size == 0)
{
DEBUG(D_tls) debug_printf("TLS: no certificate from peer (%p & %d)\n",
cert_list, cert_list_size);
if (state->verify_requirement >= VERIFY_REQUIRED)
return tls_error(US"certificate verification failed",
- "no certificate received from peer", state->host, errstr);
+ US"no certificate received from peer", state->host, errstr);
return OK;
}
-ct = gnutls_certificate_type_get(state->session);
-if (ct != GNUTLS_CRT_X509)
+if ((ct = gnutls_certificate_type_get(session)) != GNUTLS_CRT_X509)
{
- const char *ctn = gnutls_certificate_type_get_name(ct);
+ const uschar * ctn = US gnutls_certificate_type_get_name(ct);
DEBUG(D_tls)
debug_printf("TLS: peer cert not X.509 but instead \"%s\"\n", ctn);
if (state->verify_requirement >= VERIFY_REQUIRED)
DEBUG(D_tls) debug_printf("TLS: peer cert problem: %s: %s\n", \
(Label), gnutls_strerror(rc)); \
if (state->verify_requirement >= VERIFY_REQUIRED) \
- return tls_error((Label), gnutls_strerror(rc), state->host, errstr); \
+ return tls_error_gnu((Label), rc, state->host, errstr); \
return OK; \
} \
} while (0)
exim_gnutls_peer_err(US"getting size for cert DN failed");
return FAIL; /* should not happen */
}
-dn_buf = store_get_perm(sz);
+dn_buf = store_get_perm(sz, TRUE); /* tainted */
rc = gnutls_x509_crt_get_dn(crt, CS dn_buf, &sz);
exim_gnutls_peer_err(US"failed to extract certificate DN [gnutls_x509_crt_get_dn(cert 0)]");
the peer information, but that's too new for some OSes.
Arguments:
- state exim_gnutls_state_st *
- errstr where to put an error message
+ state exim_gnutls_state_st *
+ errstr where to put an error message
Returns:
FALSE if the session should be rejected
*/
static BOOL
-verify_certificate(exim_gnutls_state_st *state, uschar ** errstr)
+verify_certificate(exim_gnutls_state_st * state, uschar ** errstr)
{
int rc;
-unsigned int verify;
+uint verify;
+DEBUG(D_tls) debug_printf("TLS: checking peer certificate\n");
*errstr = NULL;
+rc = peer_status(state, errstr);
+
+if (state->verify_requirement == VERIFY_NONE)
+ return TRUE;
-if ((rc = peer_status(state, errstr)) != OK)
+if (rc != OK || !state->peerdn)
{
verify = GNUTLS_CERT_INVALID;
*errstr = US"certificate not supplied";
}
else
+
+ {
+#ifdef SUPPORT_DANE
+ if (state->verify_requirement == VERIFY_DANE && state->host)
+ {
+ /* Using dane_verify_session_crt() would be easy, as it does it all for us
+ including talking to a DNS resolver. But we want to do that bit ourselves
+ as the testsuite intercepts and fakes its own DNS environment. */
+
+ dane_state_t s;
+ dane_query_t r;
+ uint lsize;
+ const gnutls_datum_t * certlist =
+ gnutls_certificate_get_peers(state->session, &lsize);
+ int usage = tls_out.tlsa_usage;
+
+# ifdef GNUTLS_BROKEN_DANE_VALIDATION
+ /* Split the TLSA records into two sets, TA and EE selectors. Run the
+ dane-verification separately so that we know which selector verified;
+ then we know whether to do name-verification (needed for TA but not EE). */
+
+ if (usage == ((1<<DANESSL_USAGE_DANE_TA) | (1<<DANESSL_USAGE_DANE_EE)))
+ { /* a mixed-usage bundle */
+ int i, j, nrec;
+ const char ** dd;
+ int * ddl;
+
+ for(nrec = 0; state->dane_data_len[nrec]; ) nrec++;
+ nrec++;
+
+ dd = store_get(nrec * sizeof(uschar *), FALSE);
+ ddl = store_get(nrec * sizeof(int), FALSE);
+ nrec--;
+
+ if ((rc = dane_state_init(&s, 0)))
+ goto tlsa_prob;
+
+ for (usage = DANESSL_USAGE_DANE_EE;
+ usage >= DANESSL_USAGE_DANE_TA; usage--)
+ { /* take records with this usage */
+ for (j = i = 0; i < nrec; i++)
+ if (state->dane_data[i][0] == usage)
+ {
+ dd[j] = state->dane_data[i];
+ ddl[j++] = state->dane_data_len[i];
+ }
+ if (j)
+ {
+ dd[j] = NULL;
+ ddl[j] = 0;
+
+ if ((rc = dane_raw_tlsa(s, &r, (char * const *)dd, ddl, 1, 0)))
+ goto tlsa_prob;
+
+ if ((rc = dane_verify_crt_raw(s, certlist, lsize,
+ gnutls_certificate_type_get(state->session),
+ r, 0,
+ usage == DANESSL_USAGE_DANE_EE
+ ? DANE_VFLAG_ONLY_CHECK_EE_USAGE : 0,
+ &verify)))
+ {
+ DEBUG(D_tls)
+ debug_printf("TLSA record problem: %s\n", dane_strerror(rc));
+ }
+ else if (verify == 0) /* verification passed */
+ {
+ usage = 1 << usage;
+ break;
+ }
+ }
+ }
+
+ if (rc) goto tlsa_prob;
+ }
+ else
+# endif
+ {
+ if ( (rc = dane_state_init(&s, 0))
+ || (rc = dane_raw_tlsa(s, &r, state->dane_data, state->dane_data_len,
+ 1, 0))
+ || (rc = dane_verify_crt_raw(s, certlist, lsize,
+ gnutls_certificate_type_get(state->session),
+ r, 0,
+# ifdef GNUTLS_BROKEN_DANE_VALIDATION
+ usage == (1 << DANESSL_USAGE_DANE_EE)
+ ? DANE_VFLAG_ONLY_CHECK_EE_USAGE : 0,
+# else
+ 0,
+# endif
+ &verify))
+ )
+ goto tlsa_prob;
+ }
+
+ if (verify != 0) /* verification failed */
+ {
+ gnutls_datum_t str;
+ (void) dane_verification_status_print(verify, &str, 0);
+ *errstr = US str.data; /* don't bother to free */
+ goto badcert;
+ }
+
+# ifdef GNUTLS_BROKEN_DANE_VALIDATION
+ /* If a TA-mode TLSA record was used for verification we must additionally
+ verify the cert name (but not the CA chain). For EE-mode, skip it. */
+
+ if (usage & (1 << DANESSL_USAGE_DANE_EE))
+# endif
+ {
+ state->peer_dane_verified = state->peer_cert_verified = TRUE;
+ goto goodcert;
+ }
+# ifdef GNUTLS_BROKEN_DANE_VALIDATION
+ /* Assume that the name on the A-record is the one that should be matching
+ the cert. An alternate view is that the domain part of the email address
+ is also permissible. */
+
+ if (gnutls_x509_crt_check_hostname(state->tlsp->peercert,
+ CS state->host->name))
+ {
+ state->peer_dane_verified = state->peer_cert_verified = TRUE;
+ goto goodcert;
+ }
+# endif
+ }
+#endif /*SUPPORT_DANE*/
+
rc = gnutls_certificate_verify_peers2(state->session, &verify);
+ }
-/* Handle the result of verification. INVALID seems to be set as well
-as REVOKED, but leave the test for both. */
+/* Handle the result of verification. INVALID is set if any others are. */
-if (rc < 0 ||
- verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED)
- )
+if (rc < 0 || verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED))
{
state->peer_cert_verified = FALSE;
if (!*errstr)
+ {
+#ifdef GNUTLS_CERT_VFY_STATUS_PRINT
+ DEBUG(D_tls)
+ {
+ gnutls_datum_t txt;
+
+ if (gnutls_certificate_verification_status_print(verify,
+ gnutls_certificate_type_get(state->session), &txt, 0)
+ == GNUTLS_E_SUCCESS)
+ {
+ debug_printf("%s\n", txt.data);
+ gnutls_free(txt.data);
+ }
+ }
+#endif
*errstr = verify & GNUTLS_CERT_REVOKED
? US"certificate revoked" : US"certificate invalid";
+ }
DEBUG(D_tls)
debug_printf("TLS certificate verification failed (%s): peerdn=\"%s\"\n",
*errstr, state->peerdn ? state->peerdn : US"<unset>");
if (state->verify_requirement >= VERIFY_REQUIRED)
- {
- gnutls_alert_send(state->session,
- GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE);
- return FALSE;
- }
+ goto badcert;
DEBUG(D_tls)
debug_printf("TLS verify failure overridden (host in tls_try_verify_hosts)\n");
}
else
{
- if (state->exp_tls_verify_cert_hostnames)
+ /* Client side, check the server's certificate name versus the name on the
+ A-record for the connection we made. What to do for server side - what name
+ to use for client? We document that there is no such checking for server
+ side. */
+
+ if ( state->exp_tls_verify_cert_hostnames
+ && !gnutls_x509_crt_check_hostname(state->tlsp->peercert,
+ CS state->exp_tls_verify_cert_hostnames)
+ )
{
- int sep = 0;
- const uschar * list = state->exp_tls_verify_cert_hostnames;
- uschar * name;
- while ((name = string_nextinlist(&list, &sep, NULL, 0)))
- if (gnutls_x509_crt_check_hostname(state->tlsp->peercert, CS name))
- break;
- if (!name)
- {
- DEBUG(D_tls)
- debug_printf("TLS certificate verification failed: cert name mismatch\n");
- if (state->verify_requirement >= VERIFY_REQUIRED)
- {
- gnutls_alert_send(state->session,
- GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE);
- return FALSE;
- }
- return TRUE;
- }
+ DEBUG(D_tls)
+ debug_printf("TLS certificate verification failed: cert name mismatch\n");
+ if (state->verify_requirement >= VERIFY_REQUIRED)
+ goto badcert;
+ return TRUE;
}
+
state->peer_cert_verified = TRUE;
DEBUG(D_tls) debug_printf("TLS certificate verified: peerdn=\"%s\"\n",
state->peerdn ? state->peerdn : US"<unset>");
}
-state->tlsp->peerdn = state->peerdn;
+goodcert:
+ state->tlsp->peerdn = state->peerdn;
+ return TRUE;
-return TRUE;
+#ifdef SUPPORT_DANE
+tlsa_prob:
+ *errstr = string_sprintf("TLSA record problem: %s",
+ rc == DANE_E_REQUESTED_DATA_NOT_AVAILABLE ? "none usable" : dane_strerror(rc));
+#endif
+
+badcert:
+ gnutls_alert_send(state->session, GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE);
+ return FALSE;
}
rc = gnutls_server_name_get(session, sni_name, &data_len, &sni_type, 0);
if (rc != GNUTLS_E_SUCCESS)
{
- DEBUG(D_tls) {
+ DEBUG(D_tls)
if (rc == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE)
debug_printf("TLS: no SNI presented in handshake.\n");
else
debug_printf("TLS failure: gnutls_server_name_get(): %s [%d]\n",
gnutls_strerror(rc), rc);
- }
return 0;
}
/* We now have a UTF-8 string in sni_name */
old_pool = store_pool;
store_pool = POOL_PERM;
-state->received_sni = string_copyn(US sni_name, data_len);
+state->received_sni = string_copy_taint(US sni_name, TRUE);
store_pool = old_pool;
/* We set this one now so that variable expansions below will work */
-#ifndef DISABLE_OCSP
+#if !defined(DISABLE_OCSP)
static int
server_ocsp_stapling_cb(gnutls_session_t session, void * ptr,
gnutls_datum_t * ocsp_response)
{
int ret;
+DEBUG(D_tls) debug_printf("OCSP stapling callback: %s\n", US ptr);
if ((ret = gnutls_load_file(ptr, ocsp_response)) < 0)
{
uschar * yield;
exim_gnutls_state_st * state = gnutls_session_get_ptr(session);
-cert_list = gnutls_certificate_get_peers(session, &cert_list_size);
-if (cert_list)
+if ((cert_list = gnutls_certificate_get_peers(session, &cert_list_size)))
while (cert_list_size--)
{
- rc = import_cert(&cert_list[cert_list_size], &crt);
- if (rc != GNUTLS_E_SUCCESS)
+ if ((rc = import_cert(&cert_list[cert_list_size], &crt)) != GNUTLS_E_SUCCESS)
{
DEBUG(D_tls) debug_printf("TLS: peer cert problem: depth %d: %s\n",
cert_list_size, gnutls_strerror(rc));
#endif
+static gstring *
+ddump(gnutls_datum_t * d)
+{
+gstring * g = string_get((d->size+1) * 2);
+uschar * s = d->data;
+for (unsigned i = d->size; i > 0; i--, s++)
+ {
+ g = string_catn(g, US "0123456789abcdef" + (*s >> 4), 1);
+ g = string_catn(g, US "0123456789abcdef" + (*s & 0xf), 1);
+ }
+return g;
+}
+
+static void
+post_handshake_debug(exim_gnutls_state_st * state)
+{
+#ifdef SUPPORT_GNUTLS_SESS_DESC
+debug_printf("%s\n", gnutls_session_get_desc(state->session));
+#endif
+#ifdef SUPPORT_GNUTLS_KEYLOG
+# ifdef GNUTLS_TLS1_3
+if (gnutls_protocol_get_version(state->session) < GNUTLS_TLS1_3)
+#else
+if (TRUE)
+#endif
+ {
+ gnutls_datum_t c, s;
+ gstring * gc, * gs;
+ /* we only want the client random and the master secret */
+ gnutls_session_get_random(state->session, &c, &s);
+ gnutls_session_get_master_secret(state->session, &s);
+ gc = ddump(&c);
+ gs = ddump(&s);
+ debug_printf("CLIENT_RANDOM %.*s %.*s\n", (int)gc->ptr, gc->s, (int)gs->ptr, gs->s);
+ }
+else
+ debug_printf("To get keying info for TLS1.3 is hard:\n"
+ " set environment variable SSLKEYLOGFILE to a filename writable by uid exim\n"
+ " add SSLKEYLOGFILE to keep_environment in the exim config\n"
+ " run exim as root\n"
+ " if using sudo, add SSLKEYLOGFILE to env_keep in /etc/sudoers\n");
+#endif
+}
+
+
+#ifdef EXPERIMENTAL_TLS_RESUME
+static int
+tls_server_ticket_cb(gnutls_session_t sess, u_int htype, unsigned when,
+ unsigned incoming, const gnutls_datum_t * msg)
+{
+DEBUG(D_tls) debug_printf("newticket cb\n");
+tls_in.resumption |= RESUME_CLIENT_REQUESTED;
+return 0;
+}
+
+static void
+tls_server_resume_prehandshake(exim_gnutls_state_st * state)
+{
+/* Should the server offer session resumption? */
+tls_in.resumption = RESUME_SUPPORTED;
+if (verify_check_host(&tls_resumption_hosts) == OK)
+ {
+ int rc;
+ /* GnuTLS appears to not do ticket overlap, but does emit a fresh ticket when
+ an offered resumption is unacceptable. We lose one resumption per ticket
+ lifetime, and sessions cannot be indefinitely re-used. There seems to be no
+ way (3.6.7) of changing the default number of 2 TLS1.3 tickets issued, but at
+ least they go out in a single packet. */
+
+ if (!(rc = gnutls_session_ticket_enable_server(state->session,
+ &server_sessticket_key)))
+ tls_in.resumption |= RESUME_SERVER_TICKET;
+ else
+ DEBUG(D_tls)
+ debug_printf("enabling session tickets: %s\n", US gnutls_strerror(rc));
+
+ /* Try to tell if we see a ticket request */
+ gnutls_handshake_set_hook_function(state->session,
+ GNUTLS_HANDSHAKE_ANY, GNUTLS_HOOK_POST, tls_server_hook_cb);
+ }
+}
+static void
+tls_server_resume_posthandshake(exim_gnutls_state_st * state)
+{
+if (gnutls_session_resumption_requested(state->session))
+ {
+ /* This tells us the client sent a full ticket. We use a
+ callback on session-ticket request, elsewhere, to tell
+ if a client asked for a ticket. */
+
+ tls_in.resumption |= RESUME_CLIENT_SUGGESTED;
+ DEBUG(D_tls) debug_printf("client requested resumption\n");
+ }
+if (gnutls_session_is_resumed(state->session))
+ {
+ tls_in.resumption |= RESUME_USED;
+ DEBUG(D_tls) debug_printf("Session resumed\n");
+ }
+}
+#endif
/* ------------------------------------------------------------------------ */
/* Exported functions */
exim_gnutls_state_st * state = NULL;
/* Check for previous activation */
-if (tls_in.active >= 0)
+if (tls_in.active.sock >= 0)
{
- tls_error(US"STARTTLS received after TLS started", "", NULL, errstr);
+ tls_error(US"STARTTLS received after TLS started", US "", NULL, errstr);
smtp_printf("554 Already in TLS\r\n", FALSE);
return FAIL;
}
if ((rc = tls_init(NULL, tls_certificate, tls_privatekey,
NULL, tls_verify_certificates, tls_crl,
- require_ciphers, &state, errstr)) != OK) return rc;
+ require_ciphers, &state, &tls_in, errstr)) != OK) return rc;
+
+#ifdef EXPERIMENTAL_TLS_RESUME
+tls_server_resume_prehandshake(state);
+#endif
/* If this is a host for which certificate verification is mandatory or
optional, set up appropriately. */
}
/* Now negotiate the TLS session. We put our own timer on it, since it seems
-that the GnuTLS library doesn't. */
+that the GnuTLS library doesn't.
+From 3.1.0 there is gnutls_handshake_set_timeout() - but it requires you
+to set (and clear down afterwards) up a pull-timeout callback function that does
+a select, so we're no better off unless avoiding signals becomes an issue. */
gnutls_transport_set_ptr2(state->session,
(gnutls_transport_ptr_t)(long) fileno(smtp_in),
state->fd_out = fileno(smtp_out);
sigalrm_seen = FALSE;
-if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
+if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout);
do
rc = gnutls_handshake(state->session);
while (rc == GNUTLS_E_AGAIN || rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen);
-alarm(0);
+ALARM_CLR(0);
if (rc != GNUTLS_E_SUCCESS)
{
if (sigalrm_seen)
{
- tls_error(US"gnutls_handshake", "timed out", NULL, errstr);
+ tls_error(US"gnutls_handshake", US"timed out", NULL, errstr);
gnutls_db_remove_session(state->session);
}
else
{
- tls_error(US"gnutls_handshake", gnutls_strerror(rc), NULL, errstr);
+ tls_error_gnu(US"gnutls_handshake", rc, NULL, errstr);
(void) gnutls_alert_send_appropriate(state->session, rc);
gnutls_deinit(state->session);
gnutls_certificate_free_credentials(state->x509_cred);
millisleep(500);
shutdown(state->fd_out, SHUT_WR);
- for (rc = 1024; fgetc(smtp_in) != EOF && rc > 0; ) rc--; /* drain skt */
+ for (int i = 1024; fgetc(smtp_in) != EOF && i > 0; ) i--; /* drain skt */
(void)fclose(smtp_out);
(void)fclose(smtp_in);
smtp_out = smtp_in = NULL;
return FAIL;
}
-DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n");
+#ifdef EXPERIMENTAL_TLS_RESUME
+tls_server_resume_posthandshake(state);
+#endif
+
+DEBUG(D_tls) post_handshake_debug(state);
/* Verify after the fact */
-if ( state->verify_requirement != VERIFY_NONE
- && !verify_certificate(state, errstr))
+if (!verify_certificate(state, errstr))
{
if (state->verify_requirement != VERIFY_OPTIONAL)
{
*errstr);
}
-/* Figure out peer DN, and if authenticated, etc. */
-
-if ((rc = peer_status(state, NULL)) != OK) return rc;
-
/* Sets various Exim expansion variables; always safe within server */
extract_exim_vars_from_tls_state(state);
tls_client_setup_hostname_checks(host_item * host, exim_gnutls_state_st * state,
smtp_transport_options_block * ob)
{
-if (verify_check_given_host(&ob->tls_verify_cert_hostnames, host) == OK)
+if (verify_check_given_host(CUSS &ob->tls_verify_cert_hostnames, host) == OK)
{
state->exp_tls_verify_cert_hostnames =
#ifdef SUPPORT_I18N
}
+
+
+#ifdef SUPPORT_DANE
+/* Given our list of RRs from the TLSA lookup, build a lookup block in
+GnuTLS-DANE's preferred format. Hang it on the state str for later
+use in DANE verification.
+
+We point at the dnsa data not copy it, so it must remain valid until
+after verification is done.*/
+
+static BOOL
+dane_tlsa_load(exim_gnutls_state_st * state, dns_answer * dnsa)
+{
+dns_scan dnss;
+int i;
+const char ** dane_data;
+int * dane_data_len;
+
+i = 1;
+for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
+ rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)
+ ) if (rr->type == T_TLSA) i++;
+
+dane_data = store_get(i * sizeof(uschar *), FALSE);
+dane_data_len = store_get(i * sizeof(int), FALSE);
+
+i = 0;
+for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
+ rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)
+ ) if (rr->type == T_TLSA && rr->size > 3)
+ {
+ const uschar * p = rr->data;
+/*XXX need somehow to mark rr and its data as tainted. Doues this mean copying it? */
+ uint8_t usage = p[0], sel = p[1], type = p[2];
+
+ DEBUG(D_tls)
+ debug_printf("TLSA: %d %d %d size %d\n", usage, sel, type, rr->size);
+
+ if ( (usage != DANESSL_USAGE_DANE_TA && usage != DANESSL_USAGE_DANE_EE)
+ || (sel != 0 && sel != 1)
+ )
+ continue;
+ switch(type)
+ {
+ case 0: /* Full: cannot check at present */
+ break;
+ case 1: if (rr->size != 3 + 256/8) continue; /* sha2-256 */
+ break;
+ case 2: if (rr->size != 3 + 512/8) continue; /* sha2-512 */
+ break;
+ default: continue;
+ }
+
+ tls_out.tlsa_usage |= 1<<usage;
+ dane_data[i] = CS p;
+ dane_data_len[i++] = rr->size;
+ }
+
+if (!i) return FALSE;
+
+dane_data[i] = NULL;
+dane_data_len[i] = 0;
+
+state->dane_data = (char * const *)dane_data;
+state->dane_data_len = dane_data_len;
+return TRUE;
+}
+#endif
+
+
+
+#ifdef EXPERIMENTAL_TLS_RESUME
+/* On the client, get any stashed session for the given IP from hints db
+and apply it to the ssl-connection for attempted resumption. Although
+there is a gnutls_session_ticket_enable_client() interface it is
+documented as unnecessary (as of 3.6.7) as "session tickets are emabled
+by deafult". There seems to be no way to disable them, so even hosts not
+enabled by the transport option will be sent a ticket request. We will
+however avoid storing and retrieving session information. */
+
+static void
+tls_retrieve_session(tls_support * tlsp, gnutls_session_t session,
+ host_item * host, smtp_transport_options_block * ob)
+{
+tlsp->resumption = RESUME_SUPPORTED;
+if (verify_check_given_host(CUSS &ob->tls_resumption_hosts, host) == OK)
+ {
+ dbdata_tls_session * dt;
+ int len, rc;
+ open_db dbblock, * dbm_file;
+
+ DEBUG(D_tls)
+ debug_printf("check for resumable session for %s\n", host->address);
+ tlsp->host_resumable = TRUE;
+ tlsp->resumption |= RESUME_CLIENT_REQUESTED;
+ if ((dbm_file = dbfn_open(US"tls", O_RDONLY, &dbblock, FALSE, FALSE)))
+ {
+ /* Key for the db is the IP. We'd like to filter the retrieved session
+ for ticket advisory expiry, but 3.6.1 seems to give no access to that */
+
+ if ((dt = dbfn_read_with_length(dbm_file, host->address, &len)))
+ if (!(rc = gnutls_session_set_data(session,
+ CUS dt->session, (size_t)len - sizeof(dbdata_tls_session))))
+ {
+ DEBUG(D_tls) debug_printf("good session\n");
+ tlsp->resumption |= RESUME_CLIENT_SUGGESTED;
+ }
+ else DEBUG(D_tls) debug_printf("setting session resumption data: %s\n",
+ US gnutls_strerror(rc));
+ dbfn_close(dbm_file);
+ }
+ }
+}
+
+
+static void
+tls_save_session(tls_support * tlsp, gnutls_session_t session, const host_item * host)
+{
+/* TLS 1.2 - we get both the callback and the direct posthandshake call,
+but this flag is not set until the second. TLS 1.3 it's the other way about.
+Keep both calls as the session data cannot be extracted before handshake
+completes. */
+
+if (gnutls_session_get_flags(session) & GNUTLS_SFLAGS_SESSION_TICKET)
+ {
+ gnutls_datum_t tkt;
+ int rc;
+
+ DEBUG(D_tls) debug_printf("server offered session ticket\n");
+ tlsp->ticket_received = TRUE;
+ tlsp->resumption |= RESUME_SERVER_TICKET;
+
+ if (tlsp->host_resumable)
+ if (!(rc = gnutls_session_get_data2(session, &tkt)))
+ {
+ open_db dbblock, * dbm_file;
+ int dlen = sizeof(dbdata_tls_session) + tkt.size;
+ dbdata_tls_session * dt = store_get(dlen, TRUE);
+
+ DEBUG(D_tls) debug_printf("session data size %u\n", (unsigned)tkt.size);
+ memcpy(dt->session, tkt.data, tkt.size);
+ gnutls_free(tkt.data);
+
+ if ((dbm_file = dbfn_open(US"tls", O_RDWR, &dbblock, FALSE, FALSE)))
+ {
+ /* key for the db is the IP */
+ dbfn_delete(dbm_file, host->address);
+ dbfn_write(dbm_file, host->address, dt, dlen);
+ dbfn_close(dbm_file);
+
+ DEBUG(D_tls)
+ debug_printf("wrote session db (len %u)\n", (unsigned)dlen);
+ }
+ }
+ else DEBUG(D_tls)
+ debug_printf("extract session data: %s\n", US gnutls_strerror(rc));
+ }
+}
+
+
+/* With a TLS1.3 session, the ticket(s) are not seen until
+the first data read is attempted. And there's often two of them.
+Pick them up with this callback. We are also called for 1.2
+but we do nothing.
+*/
+static int
+tls_client_ticket_cb(gnutls_session_t sess, u_int htype, unsigned when,
+ unsigned incoming, const gnutls_datum_t * msg)
+{
+exim_gnutls_state_st * state = gnutls_session_get_ptr(sess);
+tls_support * tlsp = state->tlsp;
+
+DEBUG(D_tls) debug_printf("newticket cb\n");
+
+if (!tlsp->ticket_received)
+ tls_save_session(tlsp, sess, state->host);
+return 0;
+}
+
+
+static void
+tls_client_resume_prehandshake(exim_gnutls_state_st * state,
+ tls_support * tlsp, host_item * host,
+ smtp_transport_options_block * ob)
+{
+gnutls_session_set_ptr(state->session, state);
+gnutls_handshake_set_hook_function(state->session,
+ GNUTLS_HANDSHAKE_NEW_SESSION_TICKET, GNUTLS_HOOK_POST, tls_client_ticket_cb);
+
+tls_retrieve_session(tlsp, state->session, host, ob);
+}
+
+static void
+tls_client_resume_posthandshake(exim_gnutls_state_st * state,
+ tls_support * tlsp, host_item * host)
+{
+if (gnutls_session_is_resumed(state->session))
+ {
+ DEBUG(D_tls) debug_printf("Session resumed\n");
+ tlsp->resumption |= RESUME_USED;
+ }
+
+tls_save_session(tlsp, state->session, host);
+}
+#endif /* EXPERIMENTAL_TLS_RESUME */
+
+
/*************************************************
* Start a TLS session in a client *
*************************************************/
/* Called from the smtp transport after STARTTLS has been accepted.
Arguments:
- fd the fd of the connection
- host connected host (for messages)
- addr the first address (not used)
- tb transport (always smtp)
-
- errstr error string pointer
-
-Returns: OK/DEFER/FAIL (because using common functions),
- but for a client, DEFER and FAIL have the same meaning
+ cctx connection context
+ conn_args connection details
+ cookie datum for randomness (not used)
+ tlsp record details of channel configuration here; must be non-NULL
+ errstr error string pointer
+
+Returns: TRUE for success with TLS session context set in smtp context,
+ FALSE on error
*/
-int
-tls_client_start(int fd, host_item *host,
- address_item *addr ARG_UNUSED,
- transport_instance * tb,
-#ifdef EXPERIMENTAL_DANE
- dns_answer * tlsa_dnsa ARG_UNUSED,
-#endif
- uschar ** errstr)
+BOOL
+tls_client_start(client_conn_ctx * cctx, smtp_connect_args * conn_args,
+ void * cookie ARG_UNUSED,
+ tls_support * tlsp, uschar ** errstr)
{
-smtp_transport_options_block *ob =
- (smtp_transport_options_block *)tb->options_block;
+host_item * host = conn_args->host; /* for msgs and option-tests */
+transport_instance * tb = conn_args->tblock; /* always smtp or NULL */
+smtp_transport_options_block * ob = tb
+ ? (smtp_transport_options_block *)tb->options_block
+ : &smtp_transport_option_defaults;
int rc;
-exim_gnutls_state_st *state = NULL;
+exim_gnutls_state_st * state = NULL;
+uschar * cipher_list = NULL;
+
#ifndef DISABLE_OCSP
BOOL require_ocsp =
- verify_check_given_host(&ob->hosts_require_ocsp, host) == OK;
+ verify_check_given_host(CUSS &ob->hosts_require_ocsp, host) == OK;
BOOL request_ocsp = require_ocsp ? TRUE
- : verify_check_given_host(&ob->hosts_request_ocsp, host) == OK;
+ : verify_check_given_host(CUSS &ob->hosts_request_ocsp, host) == OK;
#endif
-DEBUG(D_tls) debug_printf("initialising GnuTLS as a client on fd %d\n", fd);
+DEBUG(D_tls) debug_printf("initialising GnuTLS as a client on fd %d\n", cctx->sock);
+
+#ifdef SUPPORT_DANE
+/* If dane is flagged, have either request or require dane for this host, and
+a TLSA record found. Therefore, dane verify required. Which implies cert must
+be requested and supplied, dane verify must pass, and cert verify irrelevant
+(incl. hostnames), and (caller handled) require_tls */
-if ((rc = tls_init(host, ob->tls_certificate, ob->tls_privatekey,
+if (conn_args->dane && ob->dane_require_tls_ciphers)
+ {
+ /* not using expand_check_tlsvar because not yet in state */
+ if (!expand_check(ob->dane_require_tls_ciphers, US"dane_require_tls_ciphers",
+ &cipher_list, errstr))
+ return FALSE;
+ cipher_list = cipher_list && *cipher_list
+ ? ob->dane_require_tls_ciphers : ob->tls_require_ciphers;
+ }
+#endif
+
+if (!cipher_list)
+ cipher_list = ob->tls_require_ciphers;
+
+if (tls_init(host, ob->tls_certificate, ob->tls_privatekey,
ob->tls_sni, ob->tls_verify_certificates, ob->tls_crl,
- ob->tls_require_ciphers, &state, errstr)) != OK)
- return rc;
+ cipher_list, &state, tlsp, errstr) != OK)
+ return FALSE;
{
int dh_min_bits = ob->tls_dh_min_bits;
set but both tls_verify_hosts and tls_try_verify_hosts are unset. Check only
the specified host patterns if one of them is defined */
-if ( ( state->exp_tls_verify_certificates
- && !ob->tls_verify_hosts
- && (!ob->tls_try_verify_hosts || !*ob->tls_try_verify_hosts)
- )
- || verify_check_given_host(&ob->tls_verify_hosts, host) == OK
- )
+#ifdef SUPPORT_DANE
+if (conn_args->dane && dane_tlsa_load(state, &conn_args->tlsa_dnsa))
+ {
+ DEBUG(D_tls)
+ debug_printf("TLS: server certificate DANE required.\n");
+ state->verify_requirement = VERIFY_DANE;
+ gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE);
+ }
+else
+#endif
+ if ( ( state->exp_tls_verify_certificates
+ && !ob->tls_verify_hosts
+ && (!ob->tls_try_verify_hosts || !*ob->tls_try_verify_hosts)
+ )
+ || verify_check_given_host(CUSS &ob->tls_verify_hosts, host) == OK
+ )
{
tls_client_setup_hostname_checks(host, state, ob);
DEBUG(D_tls)
state->verify_requirement = VERIFY_REQUIRED;
gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE);
}
-else if (verify_check_given_host(&ob->tls_try_verify_hosts, host) == OK)
+else if (verify_check_given_host(CUSS &ob->tls_try_verify_hosts, host) == OK)
{
tls_client_setup_hostname_checks(host, state, ob);
DEBUG(D_tls)
DEBUG(D_tls) debug_printf("TLS: will request OCSP stapling\n");
if ((rc = gnutls_ocsp_status_request_enable_client(state->session,
NULL, 0, NULL)) != OK)
- return tls_error(US"cert-status-req",
- gnutls_strerror(rc), state->host, errstr);
- tls_out.ocsp = OCSP_NOT_RESP;
+ {
+ tls_error_gnu(US"cert-status-req", rc, state->host, errstr);
+ return FALSE;
+ }
+ tlsp->ocsp = OCSP_NOT_RESP;
}
#endif
+#ifdef EXPERIMENTAL_TLS_RESUME
+tls_client_resume_prehandshake(state, tlsp, host, ob);
+#endif
+
#ifndef DISABLE_EVENT
-if (tb->event_action)
+if (tb && tb->event_action)
{
state->event_action = tb->event_action;
gnutls_session_set_ptr(state->session, state);
}
#endif
-gnutls_transport_set_ptr(state->session, (gnutls_transport_ptr_t)(long) fd);
-state->fd_in = fd;
-state->fd_out = fd;
+gnutls_transport_set_ptr(state->session, (gnutls_transport_ptr_t)(long) cctx->sock);
+state->fd_in = cctx->sock;
+state->fd_out = cctx->sock;
DEBUG(D_tls) debug_printf("about to gnutls_handshake\n");
/* There doesn't seem to be a built-in timeout on connection. */
sigalrm_seen = FALSE;
-alarm(ob->command_timeout);
+ALARM(ob->command_timeout);
do
- {
rc = gnutls_handshake(state->session);
- } while ((rc == GNUTLS_E_AGAIN) ||
- (rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen));
-alarm(0);
+while (rc == GNUTLS_E_AGAIN || rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen);
+ALARM_CLR(0);
if (rc != GNUTLS_E_SUCCESS)
+ {
if (sigalrm_seen)
{
gnutls_alert_send(state->session, GNUTLS_AL_FATAL, GNUTLS_A_USER_CANCELED);
- return tls_error(US"gnutls_handshake", "timed out", state->host, errstr);
+ tls_error(US"gnutls_handshake", US"timed out", state->host, errstr);
}
else
- return tls_error(US"gnutls_handshake", gnutls_strerror(rc), state->host, errstr);
+ tls_error_gnu(US"gnutls_handshake", rc, state->host, errstr);
+ return FALSE;
+ }
-DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n");
+DEBUG(D_tls) post_handshake_debug(state);
/* Verify late */
-if (state->verify_requirement != VERIFY_NONE &&
- !verify_certificate(state, errstr))
- return tls_error(US"certificate verification failed", *errstr, state->host, errstr);
+if (!verify_certificate(state, errstr))
+ {
+ tls_error(US"certificate verification failed", *errstr, state->host, errstr);
+ return FALSE;
+ }
#ifndef DISABLE_OCSP
-if (require_ocsp)
+if (request_ocsp)
{
DEBUG(D_tls)
{
gnutls_free(printed.data);
}
else
- (void) tls_error(US"ocsp decode", gnutls_strerror(rc), state->host, errstr);
+ (void) tls_error_gnu(US"ocsp decode", rc, state->host, errstr);
}
if (gnutls_ocsp_status_request_is_checked(state->session, 0) == 0)
{
- tls_out.ocsp = OCSP_FAILED;
- return tls_error(US"certificate status check failed", NULL, state->host, errstr);
+ tlsp->ocsp = OCSP_FAILED;
+ tls_error(US"certificate status check failed", NULL, state->host, errstr);
+ if (require_ocsp)
+ return FALSE;
+ }
+ else
+ {
+ DEBUG(D_tls) debug_printf("Passed OCSP checking\n");
+ tlsp->ocsp = OCSP_VFIED;
}
- DEBUG(D_tls) debug_printf("Passed OCSP checking\n");
- tls_out.ocsp = OCSP_VFIED;
}
#endif
-/* Figure out peer DN, and if authenticated, etc. */
-
-if ((rc = peer_status(state, errstr)) != OK)
- return rc;
+#ifdef EXPERIMENTAL_TLS_RESUME
+tls_client_resume_posthandshake(state, tlsp, host);
+#endif
/* Sets various Exim expansion variables; may need to adjust for ACL callouts */
extract_exim_vars_from_tls_state(state);
-return OK;
+cctx->tls_ctx = state;
+return TRUE;
}
daemon, to shut down the TLS library, without actually doing a shutdown (which
would tamper with the TLS session in the parent process).
-Arguments: TRUE if gnutls_bye is to be called
+Arguments:
+ ct_ctx client context pointer, or NULL for the one global server context
+ shutdown 1 if TLS close-alert is to be sent,
+ 2 if also response to be waited for
+
Returns: nothing
*/
void
-tls_close(BOOL is_server, BOOL shutdown)
+tls_close(void * ct_ctx, int shutdown)
{
-exim_gnutls_state_st *state = is_server ? &state_server : &state_client;
+exim_gnutls_state_st * state = ct_ctx ? ct_ctx : &state_server;
+tls_support * tlsp = state->tlsp;
-if (!state->tlsp || state->tlsp->active < 0) return; /* TLS was not active */
+if (!tlsp || tlsp->active.sock < 0) return; /* TLS was not active */
if (shutdown)
{
- DEBUG(D_tls) debug_printf("tls_close(): shutting down TLS\n");
- gnutls_bye(state->session, GNUTLS_SHUT_WR);
+ DEBUG(D_tls) debug_printf("tls_close(): shutting down TLS%s\n",
+ shutdown > 1 ? " (with response-wait)" : "");
+
+ ALARM(2);
+ gnutls_bye(state->session, shutdown > 1 ? GNUTLS_SHUT_RDWR : GNUTLS_SHUT_WR);
+ ALARM_CLR(0);
+ }
+
+if (!ct_ctx) /* server */
+ {
+ 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;
}
gnutls_deinit(state->session);
gnutls_certificate_free_credentials(state->x509_cred);
+tlsp->active.sock = -1;
+tlsp->active.tls_ctx = NULL;
+/* Leave bits, peercert, cipher, peerdn, certificate_verified set, for logging */
+tls_channelbinding_b64 = NULL;
-state->tlsp->active = -1;
-memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));
-if ((state_server.session == NULL) && (state_client.session == NULL))
- {
- gnutls_global_deinit();
- exim_gnutls_base_init_done = FALSE;
- }
+if (state->xfer_buffer) store_free(state->xfer_buffer);
+memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));
}
DEBUG(D_tls) debug_printf("Calling gnutls_record_recv(%p, %p, %u)\n",
state->session, state->xfer_buffer, ssl_xfer_buffer_size);
-if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
-inbytes = gnutls_record_recv(state->session, state->xfer_buffer,
- MIN(ssl_xfer_buffer_size, lim));
-alarm(0);
+sigalrm_seen = FALSE;
+if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout);
+
+do
+ inbytes = gnutls_record_recv(state->session, state->xfer_buffer,
+ MIN(ssl_xfer_buffer_size, lim));
+while (inbytes == GNUTLS_E_AGAIN);
+
+if (smtp_receive_timeout > 0) ALARM_CLR(0);
-/* Timeouts do not get this far; see command_timeout_handler().
- A zero-byte return appears to mean that the TLS session has been
- closed down, not that the socket itself has been closed down. Revert to
- non-TLS handling. */
+if (had_command_timeout) /* set by signal handler */
+ smtp_command_timeout_exit(); /* does not return */
+if (had_command_sigterm)
+ smtp_command_sigterm_exit();
+if (had_data_timeout)
+ smtp_data_timeout_exit();
+if (had_data_sigint)
+ smtp_data_sigint_exit();
+
+/* Timeouts do not get this far. A zero-byte return appears to mean that the
+TLS session has been closed down, not that the socket itself has been closed
+down. Revert to non-TLS handling. */
if (sigalrm_seen)
{
DEBUG(D_tls) debug_printf("Got tls read timeout\n");
- state->xfer_error = 1;
+ state->xfer_error = TRUE;
return FALSE;
}
else if (inbytes == 0)
{
DEBUG(D_tls) debug_printf("Got TLS_EOF\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;
-
- gnutls_deinit(state->session);
- gnutls_certificate_free_credentials(state->x509_cred);
-
- state->session = NULL;
- state->tlsp->active = -1;
- state->tlsp->bits = 0;
- state->tlsp->certificate_verified = FALSE;
- tls_channelbinding_b64 = NULL;
- state->tlsp->cipher = NULL;
- state->tlsp->peercert = NULL;
- state->tlsp->peerdn = NULL;
-
+ tls_close(NULL, TLS_NO_SHUTDOWN);
return FALSE;
}
else if (inbytes < 0)
{
+ DEBUG(D_tls) debug_printf("%s: err from gnutls_record_recv\n", __FUNCTION__);
record_io_error(state, (int) inbytes, US"recv", NULL);
- state->xfer_error = 1;
+ state->xfer_error = TRUE;
return FALSE;
}
#ifndef DISABLE_DKIM
This feeds DKIM and should be used for all message-body reads.
-Arguments: lim Maximum amount to read/bufffer
+Arguments: lim Maximum amount to read/buffer
Returns: the next character or EOF
*/
then the caller must feed DKIM.
Arguments:
+ ct_ctx client context pointer, or NULL for the one global server context
buff buffer of data
len size of buffer
Returns: the number of bytes read
- -1 after a failed read
+ -1 after a failed read, including EOF
*/
int
-tls_read(BOOL is_server, uschar *buff, size_t len)
+tls_read(void * ct_ctx, uschar *buff, size_t len)
{
-exim_gnutls_state_st *state = is_server ? &state_server : &state_client;
+exim_gnutls_state_st * state = ct_ctx ? ct_ctx : &state_server;
ssize_t inbytes;
if (len > INT_MAX)
debug_printf("Calling gnutls_record_recv(%p, %p, " SIZE_T_FMT ")\n",
state->session, buff, len);
-inbytes = gnutls_record_recv(state->session, buff, len);
+do
+ inbytes = gnutls_record_recv(state->session, buff, len);
+while (inbytes == GNUTLS_E_AGAIN);
+
if (inbytes > 0) return inbytes;
if (inbytes == 0)
{
DEBUG(D_tls) debug_printf("Got TLS_EOF\n");
}
-else record_io_error(state, (int)inbytes, US"recv", NULL);
+else
+ {
+ DEBUG(D_tls) debug_printf("%s: err from gnutls_record_recv\n", __FUNCTION__);
+ record_io_error(state, (int)inbytes, US"recv", NULL);
+ }
return -1;
}
/*
Arguments:
- is_server channel specifier
+ ct_ctx client context pointer, or NULL for the one global server context
buff buffer of data
len number of bytes
more more data expected soon
*/
int
-tls_write(BOOL is_server, const uschar *buff, size_t len, BOOL more)
+tls_write(void * ct_ctx, const uschar * buff, size_t len, BOOL more)
{
ssize_t outbytes;
size_t left = len;
-exim_gnutls_state_st *state = is_server ? &state_server : &state_client;
+exim_gnutls_state_st * state = ct_ctx ? ct_ctx : &state_server;
#ifdef SUPPORT_CORK
static BOOL corked = FALSE;
{
DEBUG(D_tls) debug_printf("gnutls_record_send(SSL, %p, " SIZE_T_FMT ")\n",
buff, left);
- outbytes = gnutls_record_send(state->session, buff, left);
+
+ do
+ outbytes = gnutls_record_send(state->session, buff, left);
+ while (outbytes == GNUTLS_E_AGAIN);
DEBUG(D_tls) debug_printf("outbytes=" SSIZE_T_FMT "\n", outbytes);
if (outbytes < 0)
{
+ DEBUG(D_tls) debug_printf("%s: gnutls_record_send err\n", __FUNCTION__);
record_io_error(state, outbytes, US"send", NULL);
return -1;
}
{
unsigned int r;
int i, needed_len;
-uschar *p;
uschar smallbuf[sizeof(r)];
if (max <= 1)
needed_len = sizeof(r);
/* Don't take 8 times more entropy than needed if int is 8 octets and we were
- * asked for a number less than 10. */
+asked for a number less than 10. */
+
for (r = max, i = 0; r; ++i)
r >>= 1;
i = (i + 7) / 8;
return vaguely_random_number_fallback(max);
}
r = 0;
-for (p = smallbuf; needed_len; --needed_len, ++p)
- {
- r *= 256;
- r += *p;
- }
+for (uschar * p = smallbuf; needed_len; --needed_len, ++p)
+ r = r * 256 + *p;
/* We don't particularly care about weighted results; if someone wants
* smooth distribution and cares enough then they should submit a patch then. */
gnutls_check_version(NULL));
}
+#endif /*!MACRO_PREDEF*/
/* vi: aw ai sw=2
*/
/* End of tls-gnu.c */
projects / exim.git / blobdiff