diff --git a/cups/http-private.h b/cups/http-private.h
index 00afed0df1..c756cd0816 100644
--- a/cups/http-private.h
+++ b/cups/http-private.h
@@ -179,13 +179,14 @@ extern "C" {
#define _HTTP_RESOLVE_FQDN 2 /* Resolve to a FQDN */
#define _HTTP_RESOLVE_FAXOUT 4 /* Resolve FaxOut service? */
-#define _HTTP_TLS_NONE 0 /* No TLS options */
-#define _HTTP_TLS_ALLOW_RC4 1 /* Allow RC4 cipher suites */
-#define _HTTP_TLS_ALLOW_SSL3 2 /* Allow SSL 3.0 */
-#define _HTTP_TLS_ALLOW_DH 4 /* Allow DH/DHE key negotiation */
-#define _HTTP_TLS_DENY_TLS10 16 /* Deny TLS 1.0 */
-#define _HTTP_TLS_DENY_CBC 32 /* Deny CBC cipher suites */
-#define _HTTP_TLS_ONLY_TLS10 64 /* Only use TLS 1.0 */
+#define _HTTP_TLS_UNCHANGED 0 /* Don't change TLS options */
+#define _HTTP_TLS_NONE 1 /* No TLS options */
+#define _HTTP_TLS_ALLOW_RC4 2 /* Allow RC4 cipher suites */
+#define _HTTP_TLS_ALLOW_SSL3 4 /* Allow SSL 3.0 */
+#define _HTTP_TLS_ALLOW_DH 8 /* Allow DH/DHE key negotiation */
+#define _HTTP_TLS_DENY_TLS10 16 /* Deny TLS 1.0 */
+#define _HTTP_TLS_DENY_CBC 32 /* Deny CBC cipher suites */
+#define _HTTP_TLS_ONLY_TLS10 64 /* Only use TLS 1.0 */
/*
@@ -442,7 +443,7 @@ extern void _httpTLSInitialize(void);
extern size_t _httpTLSPending(http_t *http);
extern int _httpTLSRead(http_t *http, char *buf, int len);
extern int _httpTLSSetCredentials(http_t *http);
-extern void _httpTLSSetOptions(int options);
+extern void _httpTLSSetOptions(unsigned int options);
extern int _httpTLSStart(http_t *http);
extern void _httpTLSStop(http_t *http);
extern int _httpTLSWrite(http_t *http, const char *buf, int len);
diff --git a/cups/tls-darwin.c b/cups/tls-darwin.c
index d2d3687a11..1be63fc309 100644
--- a/cups/tls-darwin.c
+++ b/cups/tls-darwin.c
@@ -36,24 +36,17 @@ extern char **environ; /* @private@ */
* Local globals...
*/
-static int tls_auto_create = 0;
- /* Auto-create self-signed certs? */
-static char *tls_common_name = NULL;
- /* Default common name */
+static int tls_auto_create = 0; /* Auto-create self-signed certs? */
+static char *tls_common_name = NULL; /* Default common name */
#ifdef HAVE_SECKEYCHAINOPEN
-static int tls_cups_keychain = 0;
- /* Opened the CUPS keychain? */
-static SecKeychainRef tls_keychain = NULL;
- /* Server cert keychain */
+static int tls_cups_keychain = 0; /* Opened the CUPS keychain? */
+static SecKeychainRef tls_keychain = NULL; /* Server cert keychain */
#else
-static SecIdentityRef tls_selfsigned = NULL;
- /* Temporary self-signed cert */
+static SecIdentityRef tls_selfsigned = NULL; /* Temporary self-signed cert */
#endif /* HAVE_SECKEYCHAINOPEN */
-static char *tls_keypath = NULL;
- /* Server cert keychain path */
-static _cups_mutex_t tls_mutex = _CUPS_MUTEX_INITIALIZER;
- /* Mutex for keychain/certs */
-static int tls_options = -1;/* Options for TLS connections */
+static char *tls_keypath = NULL; /* Server cert keychain path */
+static _cups_mutex_t tls_mutex = _CUPS_MUTEX_INITIALIZER; /* Mutex for keychain/certs */
+static unsigned int tls_options = _HTTP_TLS_NONE; /* Options for TLS connections */
/*
@@ -1139,7 +1132,7 @@ _httpTLSRead(http_t *http, /* I - HTTP connection */
*/
void
-_httpTLSSetOptions(int options) /* I - Options */
+_httpTLSSetOptions(unsigned int options) /* I - Options */
{
tls_options = options;
}
@@ -1169,7 +1162,7 @@ _httpTLSStart(http_t *http) /* I - HTTP connection */
DEBUG_printf(("3_httpTLSStart(http=%p)", (void *)http));
- if (tls_options < 0)
+ if ((tls_options == _HTTP_TLS_UNCHANGED) || (tls_options == _HTTP_TLS_NONE))
{
DEBUG_puts("4_httpTLSStart: Setting defaults.");
_cupsSetDefaults();
diff --git a/cups/tls-gnutls.c b/cups/tls-gnutls.c
index 3f13760b2b..cab657ce4c 100644
--- a/cups/tls-gnutls.c
+++ b/cups/tls-gnutls.c
@@ -26,16 +26,12 @@
* Local globals...
*/
-static int tls_auto_create = 0;
- /* Auto-create self-signed certs? */
-static char *tls_common_name = NULL;
- /* Default common name */
-static gnutls_x509_crl_t tls_crl = NULL;/* Certificate revocation list */
-static char *tls_keypath = NULL;
- /* Server cert keychain path */
-static _cups_mutex_t tls_mutex = _CUPS_MUTEX_INITIALIZER;
- /* Mutex for keychain/certs */
-static int tls_options = -1;/* Options for TLS connections */
+static int tls_auto_create = 0; /* Auto-create self-signed certs? */
+static char *tls_common_name = NULL; /* Default common name */
+static gnutls_x509_crl_t tls_crl = NULL; /* Certificate revocation list */
+static char *tls_keypath = NULL; /* Server cert keychain path */
+static _cups_mutex_t tls_mutex = _CUPS_MUTEX_INITIALIZER; /* Mutex for keychain/certs */
+static unsigned int tls_options = _HTTP_TLS_NONE; /* Options for TLS connections */
/*
@@ -1224,7 +1220,7 @@ _httpTLSSetCredentials(http_t *http) /* I - Connection to server */
*/
void
-_httpTLSSetOptions(int options) /* I - Options */
+_httpTLSSetOptions(unsigned int options) /* I - Options */
{
tls_options = options;
}
@@ -1248,7 +1244,7 @@ _httpTLSStart(http_t *http) /* I - Connection to server */
DEBUG_printf(("3_httpTLSStart(http=%p)", http));
- if (tls_options < 0)
+ if ((tls_options == _HTTP_TLS_UNCHANGED) || (tls_options == _HTTP_TLS_NONE))
{
DEBUG_puts("4_httpTLSStart: Setting defaults.");
_cupsSetDefaults();
@@ -1503,24 +1499,25 @@ _httpTLSStart(http_t *http) /* I - Connection to server */
return (-1);
}
- strlcpy(priority_string, "NORMAL", sizeof(priority_string));
+ strlcpy(priority_string, "NORMAL:!ANON-ECDH:!ANON-DH", sizeof(priority_string));
if (tls_options & _HTTP_TLS_DENY_TLS10)
- strlcat(priority_string, ":+VERS-TLS-ALL:-VERS-TLS1.0:-VERS-SSL3.0", sizeof(priority_string));
+ strlcat(priority_string, ":+VERS-TLS-ALL:!VERS-TLS1.0:!VERS-SSL3.0", sizeof(priority_string));
else if (tls_options & _HTTP_TLS_ALLOW_SSL3)
strlcat(priority_string, ":+VERS-TLS-ALL", sizeof(priority_string));
else if (tls_options & _HTTP_TLS_ONLY_TLS10)
- strlcat(priority_string, ":-VERS-TLS-ALL:-VERS-SSL3.0:+VERS-TLS1.0", sizeof(priority_string));
+ strlcat(priority_string, ":!VERS-TLS-ALL:!VERS-SSL3.0:+VERS-TLS1.0", sizeof(priority_string));
else
- strlcat(priority_string, ":+VERS-TLS-ALL:-VERS-SSL3.0", sizeof(priority_string));
+ strlcat(priority_string, ":+VERS-TLS-ALL:!VERS-SSL3.0", sizeof(priority_string));
- if (!(tls_options & _HTTP_TLS_ALLOW_RC4))
- strlcat(priority_string, ":-ARCFOUR-128", sizeof(priority_string));
+ if (tls_options & _HTTP_TLS_ALLOW_RC4)
+ strlcat(priority_string, ":+ARCFOUR-128", sizeof(priority_string));
+ else
+ strlcat(priority_string, ":!ARCFOUR-128", sizeof(priority_string));
- if (!(tls_options & _HTTP_TLS_ALLOW_DH))
- strlcat(priority_string, ":!ANON-DH", sizeof(priority_string));
+ /* _HTTP_TLS_ALLOW_DH cannot be implemented with gnutls */
- if (!(tls_options & _HTTP_TLS_DENY_CBC))
+ if (tls_options & _HTTP_TLS_DENY_CBC)
strlcat(priority_string, ":!AES-128-CBC:!AES-256-CBC:!CAMELLIA-128-CBC:!CAMELLIA-256-CBC:!3DES-CBC", sizeof(priority_string));
#ifdef HAVE_GNUTLS_PRIORITY_SET_DIRECT
diff --git a/cups/tls-sspi.c b/cups/tls-sspi.c
index 77b883b229..80c8cfe125 100644
--- a/cups/tls-sspi.c
+++ b/cups/tls-sspi.c
@@ -52,7 +52,7 @@
* Local globals...
*/
-static int tls_options = -1;/* Options for TLS connections */
+static unsigned int tls_options = _HTTP_TLS_NONE; /* Options for TLS connections */
/*
@@ -911,7 +911,7 @@ _httpTLSRead(http_t *http, /* I - HTTP connection */
*/
void
-_httpTLSSetOptions(int options) /* I - Options */
+_httpTLSSetOptions(unsigned int options) /* I - Options */
{
tls_options = options;
}
@@ -930,7 +930,7 @@ _httpTLSStart(http_t *http) /* I - HTTP connection */
DEBUG_printf(("3_httpTLSStart(http=%p)", http));
- if (tls_options < 0)
+ if ((tls_options == _HTTP_TLS_UNCHANGED) || (tls_options == _HTTP_TLS_NONE))
{
DEBUG_puts("4_httpTLSStart: Setting defaults.");
_cupsSetDefaults();
diff --git a/cups/usersys.c b/cups/usersys.c
index 026b4a7cc4..38e412d2e7 100644
--- a/cups/usersys.c
+++ b/cups/usersys.c
@@ -957,7 +957,10 @@ _cupsSetDefaults(void)
cg->validate_certs = cc.validate_certs;
#ifdef HAVE_SSL
- _httpTLSSetOptions(cc.ssl_options);
+ if (cc.ssl_options != _HTTP_TLS_UNCHANGED)
+ {
+ _httpTLSSetOptions(cc.ssl_options);
+ }
#endif /* HAVE_SSL */
}
@@ -1336,10 +1339,10 @@ cups_set_ssl_options(
* SSLOptions [AllowRC4] [AllowSSL3] [AllowDH] [DenyTLS1.0] [None]
*/
- int options = _HTTP_TLS_NONE; /* SSL/TLS options */
- char temp[256], /* Copy of value */
- *start, /* Start of option */
- *end; /* End of option */
+ unsigned int options = _HTTP_TLS_UNCHANGED; /* SSL/TLS options */
+ char temp[256], /* Copy of value */
+ *start, /* Start of option */
+ *end; /* End of option */
strlcpy(temp, value, sizeof(temp));
diff --git a/doc/help/man-cupsd.conf.html b/doc/help/man-cupsd.conf.html
index 908234855e..eaef850315 100644
--- a/doc/help/man-cupsd.conf.html
+++ b/doc/help/man-cupsd.conf.html
@@ -283,10 +283,10 @@
SSLOptions None
Sets encryption options.
By default, CUPS only supports encryption using TLS v1.0 or higher using known secure cipher suites.
-The AllowDH option enables cipher suites using plain Diffie-Hellman key negotiation.
-The AllowRC4 option enables the 128-bit RC4 cipher suites, which are required for some older clients that do not implement newer ones.
-The AllowSSL3 option enables SSL v3.0, which is required for some older clients that do not support TLS v1.0.
-The DenyCBC option disables all CBC cipher suites.
+The AllowDH option enables cipher suites using static Diffie-Hellman key negotiation. This option is currently only supported on macOS.
+The AllowRC4 option enables the 128-bit RC4 cipher suites, which are required for some older clients that do not implement newer ones. This option is currently not supported on Windows.
+The AllowSSL3 option enables the SSL v3.0 protocol, which is required for some older clients that do not support TLS v1.0.
+The DenyCBC option disables all CBC cipher suites. This option is currently not supported on Windows.
The DenyTLS1.0 option disables TLS v1.0 support - this sets the minimum protocol version to TLS v1.1.
SSLPort port
Listens on the specified port for encrypted connections.
diff --git a/man/cupsd.conf.man.in b/man/cupsd.conf.man.in
index 918bbee7aa..b450e3e9a0 100644
--- a/man/cupsd.conf.man.in
+++ b/man/cupsd.conf.man.in
@@ -445,10 +445,10 @@ Listens on the specified address and port for encrypted connections.
\fBSSLOptions None\fR
Sets encryption options.
By default, CUPS only supports encryption using TLS v1.0 or higher using known secure cipher suites.
-The \fIAllowDH\fR option enables cipher suites using plain Diffie-Hellman key negotiation.
-The \fIAllowRC4\fR option enables the 128-bit RC4 cipher suites, which are required for some older clients that do not implement newer ones.
-The \fIAllowSSL3\fR option enables SSL v3.0, which is required for some older clients that do not support TLS v1.0.
-The \fIDenyCBC\fR option disables all CBC cipher suites.
+The \fIAllowDH\fR option enables cipher suites using static Diffie-Hellman key negotiation. This option is currently only supported on macOS.
+The \fIAllowRC4\fR option enables the 128-bit RC4 cipher suites, which are required for some older clients that do not implement newer ones. This option is currently not supported on Windows.
+The \fIAllowSSL3\fR option enables the SSL v3.0 protocol, which is required for some older clients that do not support TLS v1.0.
+The \fIDenyCBC\fR option disables all CBC cipher suites. This option is currently not supported on Windows.
The \fIDenyTLS1.0\fR option disables TLS v1.0 support - this sets the minimum protocol version to TLS v1.1.
.\"#SSLPort
.TP 5