be set to point to content in one of these instances, as appropriate for
the stage of the process lifetime.
-Not handled here: globals tls_active, tls_bits, tls_cipher, tls_peerdn,
-tls_certificate_verified, tls_channelbinding_b64, tls_sni.
+Not handled here: global tls_channelbinding_b64.
*/
typedef struct exim_gnutls_state {
uschar *exp_tls_crl;
uschar *exp_tls_require_ciphers;
+ tls_support *tlsp; /* set in tls_init() */
+
uschar *xfer_buffer;
int xfer_buffer_lwm;
int xfer_buffer_hwm;
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL, NULL, NULL,
+ NULL,
NULL, 0, 0, 0, 0,
};
second connection. */
static exim_gnutls_state_st state_server, state_client;
-static exim_gnutls_state_st *current_global_tls_state;
/* 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
tls_cipher a string
tls_peerdn a string
tls_sni a (UTF-8) string
-Also:
- current_global_tls_state for API limitations
Argument:
state the relevant exim_gnutls_state_st *
*/
static void
-extract_exim_vars_from_tls_state(exim_gnutls_state_st *state)
+extract_exim_vars_from_tls_state(exim_gnutls_state_st *state, BOOL is_server)
{
gnutls_cipher_algorithm_t cipher;
#ifdef HAVE_GNUTLS_SESSION_CHANNEL_BINDING
gnutls_datum_t channel;
#endif
-current_global_tls_state = state;
-
-tls_active = state->fd_out;
+state->tlsp->active = state->fd_out;
cipher = gnutls_cipher_get(state->session);
/* returns size in "bytes" */
-tls_bits = gnutls_cipher_get_key_size(cipher) * 8;
+state->tlsp->bits = gnutls_cipher_get_key_size(cipher) * 8;
-tls_cipher = state->ciphersuite;
+state->tlsp->cipher = state->ciphersuite;
-DEBUG(D_tls) debug_printf("cipher: %s\n", tls_cipher);
+DEBUG(D_tls) debug_printf("cipher: %s\n", state->ciphersuite);
-tls_certificate_verified = state->peer_cert_verified;
+state->tlsp->certificate_verified = state->peer_cert_verified;
/* 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. */
}
#endif
-tls_peerdn = state->peerdn;
-
-tls_sni = state->received_sni;
+state->tlsp->peerdn = state->peerdn;
+state->tlsp->sni = state->received_sni;
}
{
if (!state->received_sni)
{
- if (state->tls_certificate && Ustrstr(state->tls_certificate, US"tls_sni"))
+ if (state->tls_certificate &&
+ (Ustrstr(state->tls_certificate, US"tls_sni") ||
+ Ustrstr(state->tls_certificate, US"tls_in_sni") ||
+ Ustrstr(state->tls_certificate, US"tls_out_sni")
+ ))
{
DEBUG(D_tls) debug_printf("We will re-expand TLS session files if we receive SNI.\n");
state->trigger_sni_changes = TRUE;
cas CA certs file
crl CRL file
require_ciphers tls_require_ciphers setting
+ caller_state returned state-info structure
Returns: OK/DEFER/FAIL
*/
{
state = &state_client;
memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));
+ state->tlsp = &tls_out;
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;
DEBUG(D_tls) debug_printf("initialising GnuTLS server session\n");
rc = gnutls_init(&state->session, GNUTLS_SERVER);
}
/* set SNI in client, only */
if (host)
{
- if (!expand_check_tlsvar(tls_sni))
+ if (!expand_check(state->tlsp->sni, "tls_out_sni", &state->exp_tls_sni))
return DEFER;
if (state->exp_tls_sni && *state->exp_tls_sni)
{
}
*caller_state = state;
-/* needs to happen before callbacks during handshake */
-current_global_tls_state = state;
return OK;
}
store_pool = POOL_PERM;
state->ciphersuite = string_copy(cipherbuf);
store_pool = old_pool;
-tls_cipher = state->ciphersuite;
+state->tlsp->cipher = state->ciphersuite;
/* tls_peerdn */
cert_list = gnutls_certificate_get_peers(state->session, &cert_list_size);
state->peerdn ? state->peerdn : US"<unset>");
}
-tls_peerdn = state->peerdn;
+state->tlsp->peerdn = state->peerdn;
return TRUE;
}
For inability to get SNI information, we return 0.
We only return non-zero if re-setup failed.
+Only used for server-side TLS.
*/
static int
{
char sni_name[MAX_HOST_LEN];
size_t data_len = MAX_HOST_LEN;
-exim_gnutls_state_st *state = current_global_tls_state;
+exim_gnutls_state_st *state = &state_server;
unsigned int sni_type;
int rc, old_pool;
store_pool = old_pool;
/* We set this one now so that variable expansions below will work */
-tls_sni = state->received_sni;
+state->tlsp->sni = state->received_sni;
DEBUG(D_tls) debug_printf("Received TLS SNI \"%s\"%s\n", sni_name,
state->trigger_sni_changes ? "" : " (unused for certificate selection)");
exim_gnutls_state_st *state = NULL;
/* Check for previous activation */
-/* nb: this will not be TLS callout safe, needs reworking as part of that. */
-
-if (tls_active >= 0)
+if (tls_in.active >= 0)
{
tls_error(US"STARTTLS received after TLS started", "", NULL);
smtp_printf("554 Already in TLS\r\n");
the response. Other smtp_printf() calls do not need it, because in non-TLS
mode, the fflush() happens when smtp_getc() is called. */
-if (!tls_on_connect)
+if (!state->tlsp->on_connect)
{
smtp_printf("220 TLS go ahead\r\n");
- fflush(smtp_out);
+ fflush(smtp_out); /*XXX JGH */
}
/* Now negotiate the TLS session. We put our own timer on it, since it seems
/* Sets various Exim expansion variables; always safe within server */
-extract_exim_vars_from_tls_state(state);
+extract_exim_vars_from_tls_state(state, TRUE);
/* TLS has been set up. Adjust the input functions to read via TLS,
and initialize appropriately. */
verify_certs file for certificate verify
verify_crl CRL for verify
require_ciphers list of allowed ciphers or NULL
+ dh_min_bits minimum number of bits acceptable in server's DH prime
timeout startup timeout
Returns: OK/DEFER/FAIL (because using common functions),
address_item *addr ARG_UNUSED, uschar *dhparam ARG_UNUSED,
uschar *certificate, uschar *privatekey, uschar *sni,
uschar *verify_certs, uschar *verify_crl,
- uschar *require_ciphers, int timeout)
+ uschar *require_ciphers, int dh_min_bits, int timeout)
{
int rc;
const char *error;
sni, verify_certs, verify_crl, require_ciphers, &state);
if (rc != OK) return rc;
-gnutls_dh_set_prime_bits(state->session, EXIM_CLIENT_DH_MIN_BITS);
+if (dh_min_bits < EXIM_CLIENT_DH_MIN_MIN_BITS)
+ {
+ DEBUG(D_tls)
+ debug_printf("WARNING: tls_dh_min_bits far too low, clamping %d up to %d\n",
+ dh_min_bits, EXIM_CLIENT_DH_MIN_MIN_BITS);
+ dh_min_bits = EXIM_CLIENT_DH_MIN_MIN_BITS;
+ }
+
+DEBUG(D_tls) debug_printf("Setting D-H prime minimum acceptable bits to %d\n",
+ dh_min_bits);
+gnutls_dh_set_prime_bits(state->session, dh_min_bits);
if (verify_certs == NULL)
{
/* Sets various Exim expansion variables; may need to adjust for ACL callouts */
-extract_exim_vars_from_tls_state(state);
+extract_exim_vars_from_tls_state(state, FALSE);
return OK;
}
*/
void
-tls_close(BOOL shutdown)
+tls_close(BOOL is_server, BOOL shutdown)
{
-exim_gnutls_state_st *state = current_global_tls_state;
+exim_gnutls_state_st *state = is_server ? &state_server : &state_client;
-if (tls_active < 0) return; /* TLS was not active */
+if (!state->tlsp || state->tlsp->active < 0) return; /* TLS was not active */
if (shutdown)
{
gnutls_deinit(state->session);
+state->tlsp->active = -1;
memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));
if ((state_server.session == NULL) && (state_client.session == NULL))
exim_gnutls_base_init_done = FALSE;
}
-tls_active = -1;
}
/* This gets the next byte from the TLS input buffer. If the buffer is empty,
it refills the buffer via the GnuTLS reading function.
+Only used by the server-side TLS.
This feeds DKIM and should be used for all message-body reads.
int
tls_getc(void)
{
-exim_gnutls_state_st *state = current_global_tls_state;
+exim_gnutls_state_st *state = &state_server;
if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm)
{
ssize_t inbytes;
gnutls_deinit(state->session);
state->session = NULL;
- tls_active = -1;
- tls_bits = 0;
- tls_certificate_verified = FALSE;
- tls_channelbinding_b64 = NULL;
- tls_cipher = NULL;
- tls_peerdn = NULL;
+ state->tlsp->active = -1;
+ state->tlsp->bits = 0;
+ state->tlsp->certificate_verified = FALSE;
+ tls_channelbinding_b64 = NULL; /*XXX JGH */
+ state->tlsp->cipher = NULL;
+ state->tlsp->peerdn = NULL;
return smtp_getc();
}
/* This does not feed DKIM, so if the caller uses this for reading message body,
then the caller must feed DKIM.
+
Arguments:
buff buffer of data
len size of buffer
*/
int
-tls_read(uschar *buff, size_t len)
+tls_read(BOOL is_server, uschar *buff, size_t len)
{
-exim_gnutls_state_st *state = current_global_tls_state;
+exim_gnutls_state_st *state = is_server ? &state_server : &state_client;
ssize_t inbytes;
if (len > INT_MAX)
/*
Arguments:
+ is_server channel specifier
buff buffer of data
len number of bytes
*/
int
-tls_write(const uschar *buff, size_t len)
+tls_write(BOOL is_server, const uschar *buff, size_t len)
{
ssize_t outbytes;
size_t left = len;
-exim_gnutls_state_st *state = current_global_tls_state;
+exim_gnutls_state_st *state = is_server ? &state_server : &state_client;
DEBUG(D_tls) debug_printf("tls_do_write(%p, " SIZE_T_FMT ")\n", buff, left);
while (left > 0)