* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) The Exim Maintainers 2019 */
+/* Copyright (c) The Exim Maintainers 2019 - 2021 */
/* Copyright (c) University of Cambridge 1995 - 2018 */
/* See the file NOTICE for conditions of use and distribution. */
*/
#include "../exim.h"
-#define CHANNELBIND_HACK
#ifndef AUTH_GSASL
/* dummy function to satisfy compilers when we link in an "empty" file. */
#include "gsasl_exim.h"
-#if GSASL_VERSION_MINOR >= 9
+#if GSASL_VERSION_MINOR >= 10
+# define EXIM_GSASL_HAVE_SCRAM_SHA_256
+# define EXIM_GSASL_SCRAM_S_KEY
+
+#elif GSASL_VERSION_MINOR == 9
# define EXIM_GSASL_HAVE_SCRAM_SHA_256
# if GSASL_VERSION_PATCH >= 1
# define EXIM_GSASL_SCRAM_S_KEY
# endif
+# if GSASL_VERSION_PATCH < 2
+# define CHANNELBIND_HACK
+# endif
+
+#else
+# define CHANNELBIND_HACK
#endif
+/* Convenience for testing strings */
+
+#define STREQIC(Foo, Bar) (strcmpic((Foo), (Bar)) == 0)
+
/* Authenticator-specific options. */
/* I did have server_*_condition options for various mechanisms, but since
we only ever handle one mechanism at a time, I didn't see the point in keeping
that. In case someone sees a point, I've left the condition_check() API
alone. */
+#define LOFF(field) OPT_OFF(auth_gsasl_options_block, field)
+
optionlist auth_gsasl_options[] = {
- { "client_authz", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, client_authz)) },
- { "client_channelbinding", opt_bool,
- (void *)(offsetof(auth_gsasl_options_block, client_channelbinding)) },
- { "client_password", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, client_password)) },
- { "client_spassword", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, client_spassword)) },
- { "client_username", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, client_username)) },
-
- { "server_channelbinding", opt_bool,
- (void *)(offsetof(auth_gsasl_options_block, server_channelbinding)) },
- { "server_hostname", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, server_hostname)) },
+ { "client_authz", opt_stringptr, LOFF(client_authz) },
+ { "client_channelbinding", opt_bool, LOFF(client_channelbinding) },
+ { "client_password", opt_stringptr, LOFF(client_password) },
+ { "client_spassword", opt_stringptr, LOFF(client_spassword) },
+ { "client_username", opt_stringptr, LOFF(client_username) },
+
+ { "server_channelbinding", opt_bool, LOFF(server_channelbinding) },
+ { "server_hostname", opt_stringptr, LOFF(server_hostname) },
#ifdef EXIM_GSASL_SCRAM_S_KEY
- { "server_key", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, server_key)) },
+ { "server_key", opt_stringptr, LOFF(server_key) },
#endif
- { "server_mech", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, server_mech)) },
- { "server_password", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, server_password)) },
- { "server_realm", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, server_realm)) },
- { "server_scram_iter", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, server_scram_iter)) },
- { "server_scram_salt", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, server_scram_salt)) },
+ { "server_mech", opt_stringptr, LOFF(server_mech) },
+ { "server_password", opt_stringptr, LOFF(server_password) },
+ { "server_realm", opt_stringptr, LOFF(server_realm) },
+ { "server_scram_iter", opt_stringptr, LOFF(server_scram_iter) },
+ { "server_scram_salt", opt_stringptr, LOFF(server_scram_salt) },
#ifdef EXIM_GSASL_SCRAM_S_KEY
- { "server_skey", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, server_s_key)) },
+ { "server_skey", opt_stringptr, LOFF(server_s_key) },
#endif
- { "server_service", opt_stringptr,
- (void *)(offsetof(auth_gsasl_options_block, server_service)) }
+ { "server_service", opt_stringptr, LOFF(server_service) }
};
int auth_gsasl_options_count =
"GNU SASL does not support mechanism \"%s\"",
ablock->name, ob->server_mech);
-ablock->server = TRUE;
-
-if ( !ablock->server_condition
- && ( streqic(ob->server_mech, US"EXTERNAL")
- || streqic(ob->server_mech, US"ANONYMOUS")
- || streqic(ob->server_mech, US"PLAIN")
- || streqic(ob->server_mech, US"LOGIN")
- ) )
+if (ablock->server_condition)
+ ablock->server = TRUE;
+else if( ob->server_mech
+ && !STREQIC(ob->server_mech, US"EXTERNAL")
+ && !STREQIC(ob->server_mech, US"ANONYMOUS")
+ && !STREQIC(ob->server_mech, US"PLAIN")
+ && !STREQIC(ob->server_mech, US"LOGIN")
+ )
{
+ /* At present, for mechanisms we don't panic on absence of server_condition;
+ need to figure out the most generically correct approach to deciding when
+ it's critical and when it isn't. Eg, for simple validation (PLAIN mechanism,
+ etc) it clearly is critical.
+ */
+
ablock->server = FALSE;
HDEBUG(D_auth) debug_printf("%s authenticator: "
"Need server_condition for %s mechanism\n",
which properties will be needed. */
if ( !ob->server_realm
- && streqic(ob->server_mech, US"DIGEST-MD5"))
+ && STREQIC(ob->server_mech, US"DIGEST-MD5"))
{
ablock->server = FALSE;
HDEBUG(D_auth) debug_printf("%s authenticator: "
ablock->name, ob->server_mech);
}
-/* At present, for mechanisms we don't panic on absence of server_condition;
-need to figure out the most generically correct approach to deciding when
-it's critical and when it isn't. Eg, for simple validation (PLAIN mechanism,
-etc) it clearly is critical.
-*/
-
ablock->client = ob->client_username && ob->client_password;
}
{
switch (prop)
{
- case GSASL_AUTHID: return US"AUTHID";
- case GSASL_AUTHZID: return US"AUTHZID";
- case GSASL_PASSWORD: return US"PASSWORD";
- case GSASL_ANONYMOUS_TOKEN: return US"ANONYMOUS_TOKEN";
- case GSASL_SERVICE: return US"SERVICE";
- case GSASL_HOSTNAME: return US"HOSTNAME";
- case GSASL_GSSAPI_DISPLAY_NAME: return US"GSSAPI_DISPLAY_NAME";
- case GSASL_PASSCODE: return US"PASSCODE";
- case GSASL_SUGGESTED_PIN: return US"SUGGESTED_PIN";
- case GSASL_PIN: return US"PIN";
- case GSASL_REALM: return US"REALM";
- case GSASL_DIGEST_MD5_HASHED_PASSWORD: return US"DIGEST_MD5_HASHED_PASSWORD";
- case GSASL_QOPS: return US"QOPS";
- case GSASL_QOP: return US"QOP";
- case GSASL_SCRAM_ITER: return US"SCRAM_ITER";
- case GSASL_SCRAM_SALT: return US"SCRAM_SALT";
- case GSASL_SCRAM_SALTED_PASSWORD: return US"SCRAM_SALTED_PASSWORD";
-#ifdef EXIM_GSASL_SCRAM_S_KEY
- case GSASL_SCRAM_STOREDKEY: return US"SCRAM_STOREDKEY";
- case GSASL_SCRAM_SERVERKEY: return US"SCRAM_SERVERKEY";
-#endif
- case GSASL_CB_TLS_UNIQUE: return US"CB_TLS_UNIQUE";
- case GSASL_SAML20_IDP_IDENTIFIER: return US"SAML20_IDP_IDENTIFIER";
- case GSASL_SAML20_REDIRECT_URL: return US"SAML20_REDIRECT_URL";
- case GSASL_OPENID20_REDIRECT_URL: return US"OPENID20_REDIRECT_URL";
- case GSASL_OPENID20_OUTCOME_DATA: return US"OPENID20_OUTCOME_DATA";
- case GSASL_SAML20_AUTHENTICATE_IN_BROWSER: return US"SAML20_AUTHENTICATE_IN_BROWSER";
- case GSASL_OPENID20_AUTHENTICATE_IN_BROWSER: return US"OPENID20_AUTHENTICATE_IN_BROWSER";
+ case GSASL_AUTHID: return US"AUTHID";
+ case GSASL_AUTHZID: return US"AUTHZID";
+ case GSASL_PASSWORD: return US"PASSWORD";
+ case GSASL_ANONYMOUS_TOKEN: return US"ANONYMOUS_TOKEN";
+ case GSASL_SERVICE: return US"SERVICE";
+ case GSASL_HOSTNAME: return US"HOSTNAME";
+ case GSASL_GSSAPI_DISPLAY_NAME: return US"GSSAPI_DISPLAY_NAME";
+ case GSASL_PASSCODE: return US"PASSCODE";
+ case GSASL_SUGGESTED_PIN: return US"SUGGESTED_PIN";
+ case GSASL_PIN: return US"PIN";
+ case GSASL_REALM: return US"REALM";
+ case GSASL_DIGEST_MD5_HASHED_PASSWORD: return US"DIGEST_MD5_HASHED_PASSWORD";
+ case GSASL_QOPS: return US"QOPS";
+ case GSASL_QOP: return US"QOP";
+ case GSASL_SCRAM_ITER: return US"SCRAM_ITER";
+ case GSASL_SCRAM_SALT: return US"SCRAM_SALT";
+ case GSASL_SCRAM_SALTED_PASSWORD: return US"SCRAM_SALTED_PASSWORD";
#ifdef EXIM_GSASL_SCRAM_S_KEY
- case GSASL_SCRAM_CLIENTKEY: return US"SCRAM_CLIENTKEY";
+ case GSASL_SCRAM_STOREDKEY: return US"SCRAM_STOREDKEY";
+ case GSASL_SCRAM_SERVERKEY: return US"SCRAM_SERVERKEY";
#endif
- case GSASL_VALIDATE_SIMPLE: return US"VALIDATE_SIMPLE";
- case GSASL_VALIDATE_EXTERNAL: return US"VALIDATE_EXTERNAL";
- case GSASL_VALIDATE_ANONYMOUS: return US"VALIDATE_ANONYMOUS";
- case GSASL_VALIDATE_GSSAPI: return US"VALIDATE_GSSAPI";
- case GSASL_VALIDATE_SECURID: return US"VALIDATE_SECURID";
- case GSASL_VALIDATE_SAML20: return US"VALIDATE_SAML20";
- case GSASL_VALIDATE_OPENID20: return US"VALIDATE_OPENID20";
+ case GSASL_CB_TLS_UNIQUE: return US"CB_TLS_UNIQUE";
+ case GSASL_SAML20_IDP_IDENTIFIER: return US"SAML20_IDP_IDENTIFIER";
+ case GSASL_SAML20_REDIRECT_URL: return US"SAML20_REDIRECT_URL";
+ case GSASL_OPENID20_REDIRECT_URL: return US"OPENID20_REDIRECT_URL";
+ case GSASL_OPENID20_OUTCOME_DATA: return US"OPENID20_OUTCOME_DATA";
+ case GSASL_SAML20_AUTHENTICATE_IN_BROWSER: return US"SAML20_AUTHENTICATE_IN_BROWSER";
+ case GSASL_OPENID20_AUTHENTICATE_IN_BROWSER: return US"OPENID20_AUTHENTICATE_IN_BROWSER";
+ case GSASL_VALIDATE_SIMPLE: return US"VALIDATE_SIMPLE";
+ case GSASL_VALIDATE_EXTERNAL: return US"VALIDATE_EXTERNAL";
+ case GSASL_VALIDATE_ANONYMOUS: return US"VALIDATE_ANONYMOUS";
+ case GSASL_VALIDATE_GSSAPI: return US"VALIDATE_GSSAPI";
+ case GSASL_VALIDATE_SECURID: return US"VALIDATE_SECURID";
+ case GSASL_VALIDATE_SAML20: return US"VALIDATE_SAML20";
+ case GSASL_VALIDATE_OPENID20: return US"VALIDATE_OPENID20";
}
return CUS string_sprintf("(unknown prop: %d)", (int)prop);
}
#ifndef DISABLE_TLS
if (tls_in.channelbinding && ob->server_channelbinding)
{
-# ifdef EXPERIMENTAL_TLS_RESUME
+# ifndef DISABLE_TLS_RESUME
if (!tls_in.ext_master_secret && tls_in.resumption == RESUME_USED)
{ /* per RFC 7677 section 4 */
HDEBUG(D_auth) debug_printf(
}
# endif
# ifdef CHANNELBIND_HACK
-/* This is a gross hack to get around the library a) requiring that
-c-b was already set, at the _start() call, and b) caching a b64'd
-version of the binding then which it never updates. */
+/* This is a gross hack to get around the library before 1.9.2
+a) requiring that c-b was already set, at the _start() call, and
+b) caching a b64'd version of the binding then which it never updates. */
gsasl_callback_hook_set(gsasl_ctx, tls_in.channelbinding);
# endif
would then result in mechanism name changes on a library update, we
have little choice but to default it off and let the admin choose to
enable it. *sigh*
+
+ Earlier library versions need this set early, during the _start() call,
+ so we had to misuse gsasl_callback_hook_set/get() as a data transfer
+ mech for the callback done at that time to get the bind-data. More recently
+ the callback is done (if needed) during the first gsasl_stop(). We know
+ the bind-data here so can set it (and should not get a callback).
*/
if (ob->server_channelbinding)
{
}
+/* Set the "next" $auth[n] and increment expand_nmax */
+
static void
set_exim_authvar_from_prop(Gsasl_session * sctx, Gsasl_property prop)
{
uschar * propval = US gsasl_property_fast(sctx, prop);
int i = expand_nmax, j = i + 1;
propval = propval ? string_copy(propval) : US"";
-auth_vars[i] = expand_nstring[j] = propval;
+HDEBUG(D_auth) debug_printf("auth[%d] <= %s'%s'\n",
+ j, gsasl_prop_code_to_name(prop), propval);
+expand_nstring[j] = propval;
expand_nlength[j] = Ustrlen(propval);
+if (i < AUTH_VARS) auth_vars[i] = propval;
expand_nmax = j;
}
server_callback(Gsasl *ctx, Gsasl_session *sctx, Gsasl_property prop,
auth_instance *ablock)
{
-char *tmps;
-uschar *s, *propval;
+char * tmps;
+uschar * s;
int cbrc = GSASL_NO_CALLBACK;
-auth_gsasl_options_block *ob =
+auth_gsasl_options_block * ob =
(auth_gsasl_options_block *)(ablock->options_block);
HDEBUG(D_auth) debug_printf("GNU SASL callback %s for %s/%s as server\n",
for memory wiping, so expanding strings will leave stuff laying around.
But no need to compound the problem, so get rid of the one we can. */
- memset(tmps, '\0', strlen(tmps));
+ if (US tmps != s) memset(tmps, '\0', strlen(tmps));
cbrc = GSASL_OK;
break;
unsigned flags, uschar * buffer, int buffsize)
{
uschar * s;
-int rc;
if (!val) return !!(flags & PROP_OPTIONAL);
if (!(s = expand_string(val)) || !(flags & PROP_OPTIONAL) && !*s)
#ifndef DISABLE_TLS
if (tls_out.channelbinding && ob->client_channelbinding)
{
-# ifdef EXPERIMENTAL_TLS_RESUME
+# ifndef DISABLE_TLS_RESUME
if (!tls_out.ext_master_secret && tls_out.resumption == RESUME_USED)
- { /* per RFC 7677 section 4 */
+ { /* Per RFC 7677 section 4. See also RFC 7627, "Triple Handshake"
+ vulnerability, and https://www.mitls.org/pages/attacks/3SHAKE */
string_format(buffer, buffsize, "%s",
"channel binding not usable on resumed TLS without extended-master-secret");
return FAIL;
}
# endif
# ifdef CHANNELBIND_HACK
- /* This is a gross hack to get around the library a) requiring that
- c-b was already set, at the _start() call, and b) caching a b64'd
- version of the binding then which it never updates. */
+ /* This is a gross hack to get around the library before 1.9.2
+ a) requiring that c-b was already set, at the _start() call, and
+ b) caching a b64'd version of the binding then which it never updates. */
gsasl_callback_hook_set(gsasl_ctx, tls_out.channelbinding);
# endif
/* Set properties */
-if ( !set_client_prop(sctx, GSASL_SCRAM_SALTED_PASSWORD, ob->client_spassword,
- 0, buffer, buffsize)
- &&
- !set_client_prop(sctx, GSASL_PASSWORD, ob->client_password,
+if ( !set_client_prop(sctx, GSASL_PASSWORD, ob->client_password,
0, buffer, buffsize)
|| !set_client_prop(sctx, GSASL_AUTHID, ob->client_username,
0, buffer, buffsize)
}
done:
-HDEBUG(D_auth)
+if (yield == OK)
{
- const uschar * s = CUS gsasl_property_fast(sctx, GSASL_SCRAM_SALTED_PASSWORD);
- if (s) debug_printf(" - SaltedPassword: '%s'\n", s);
+ expand_nmax = 0;
+ set_exim_authvar_from_prop(sctx, GSASL_AUTHID);
+ set_exim_authvar_from_prop(sctx, GSASL_SCRAM_ITER);
+ set_exim_authvar_from_prop(sctx, GSASL_SCRAM_SALT);
+ set_exim_authvar_from_prop(sctx, GSASL_SCRAM_SALTED_PASSWORD);
}
gsasl_finish(sctx);
gsasl_prop_code_to_name(prop), ablock->name, ablock->public_name);
switch (prop)
{
- case GSASL_CB_TLS_UNIQUE:
+ case GSASL_CB_TLS_UNIQUE: /*XXX should never get called for this */
HDEBUG(D_auth)
debug_printf(" filling in\n");
gsasl_property_set(sctx, GSASL_CB_TLS_UNIQUE, CCS tls_out.channelbinding);
break;
+ case GSASL_SCRAM_SALTED_PASSWORD:
+ {
+ uschar * client_spassword =
+ ((auth_gsasl_options_block *) ablock->options_block)->client_spassword;
+ uschar dummy[4];
+ HDEBUG(D_auth) if (!client_spassword)
+ debug_printf(" client_spassword option unset\n");
+ if (client_spassword)
+ {
+ expand_nmax = 0;
+ set_exim_authvar_from_prop(sctx, GSASL_AUTHID);
+ set_exim_authvar_from_prop(sctx, GSASL_SCRAM_ITER);
+ set_exim_authvar_from_prop(sctx, GSASL_SCRAM_SALT);
+ set_client_prop(sctx, GSASL_SCRAM_SALTED_PASSWORD, client_spassword,
+ 0, dummy, sizeof(dummy));
+ for (int i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL;
+ expand_nmax = 0;
+ }
+ break;
+ }
default:
HDEBUG(D_auth)
debug_printf(" not providing one\n");
git://git.exim.org / exim.git / blobdiff