remove support for SSLv3

it's insecure and default builds of openssl don't include it any more.

NEWS

@@ -3,6 +3,7 @@
 The 'isync' compatibility wrapper was removed.
 
 Added support for disabling TLS v1.3 - adjust SSLVersions if you set it.
+Removed support for obsolete/insecure SSL v3.
 
 The IMAP '$Forwarded' / Maildir 'P' (passed) flag is supported now.
 

src/drv_imap.c

@@ -3194,7 +3194,7 @@ imap_parse_store( conffile_t *cfg, store_conf_t **storep )
 #ifdef HAVE_LIBSSL
 	/* Legacy SSL options */
 	int require_ssl = -1, use_imaps = -1;
-	int use_sslv3 = -1, use_tlsv1 = -1, use_tlsv11 = -1, use_tlsv12 = -1, use_tlsv13 = -1;
+	int use_tlsv1 = -1, use_tlsv11 = -1, use_tlsv12 = -1, use_tlsv13 = -1;
 #endif
 	/* Legacy SASL option */
 	int require_cram = -1;
@@ -3234,7 +3234,7 @@ imap_parse_store( conffile_t *cfg, store_conf_t **storep )
 				arg += 6;
 				server->ssl_type = SSL_IMAPS;
 				if (server->sconf.ssl_versions == -1)
-					server->sconf.ssl_versions = SSLv3 | TLSv1 | TLSv1_1 | TLSv1_2 | TLSv1_3;
+					server->sconf.ssl_versions = TLSv1 | TLSv1_1 | TLSv1_2 | TLSv1_3;
 			} else
 #endif
 			if (starts_with( arg, -1, "imap:", 5 ))
@@ -3326,7 +3326,7 @@ imap_parse_store( conffile_t *cfg, store_conf_t **storep )
 				if (!strcasecmp( "SSLv2", arg )) {
 					warn( "Warning: SSLVersion SSLv2 is no longer supported\n" );
 				} else if (!strcasecmp( "SSLv3", arg )) {
-					server->sconf.ssl_versions |= SSLv3;
+					warn( "Warning: SSLVersion SSLv3 is no longer supported\n" );
 				} else if (!strcasecmp( "TLSv1", arg )) {
 					server->sconf.ssl_versions |= TLSv1;
 				} else if (!strcasecmp( "TLSv1.1", arg )) {
@@ -3347,7 +3347,7 @@ imap_parse_store( conffile_t *cfg, store_conf_t **storep )
 		else if (!strcasecmp( "UseSSLv2", cfg->cmd ))
 			warn( "Warning: UseSSLv2 is no longer supported\n" );
 		else if (!strcasecmp( "UseSSLv3", cfg->cmd ))
-			use_sslv3 = parse_bool( cfg );
+			warn( "Warning: UseSSLv3 is no longer supported\n" );
 		else if (!strcasecmp( "UseTLSv1", cfg->cmd ))
 			use_tlsv1 = parse_bool( cfg );
 		else if (!strcasecmp( "UseTLSv1.1", cfg->cmd ))
@@ -3416,7 +3416,7 @@ imap_parse_store( conffile_t *cfg, store_conf_t **storep )
 			return 1;
 		}
 #ifdef HAVE_LIBSSL
-		if ((use_sslv3 & use_tlsv1 & use_tlsv11 & use_tlsv12 & use_tlsv13) != -1 || use_imaps >= 0 || require_ssl >= 0) {
+		if ((use_tlsv1 & use_tlsv11 & use_tlsv12 & use_tlsv13) != -1 || use_imaps >= 0 || require_ssl >= 0) {
 			if (server->ssl_type >= 0 || server->sconf.ssl_versions >= 0) {
 				error( "%s '%s': The deprecated UseSSL*, UseTLS*, UseIMAPS, and RequireSSL options are mutually exclusive with SSLType and SSLVersions.\n", type, name );
 				cfg->err = 1;
@@ -3424,7 +3424,6 @@ imap_parse_store( conffile_t *cfg, store_conf_t **storep )
 			}
 			warn( "Notice: %s '%s': UseSSL*, UseTLS*, UseIMAPS, and RequireSSL are deprecated. Use SSLType and SSLVersions instead.\n", type, name );
 			server->sconf.ssl_versions =
-					(use_sslv3 != 1 ? 0 : SSLv3) |
 					(use_tlsv1 == 0 ? 0 : TLSv1) |
 					(use_tlsv11 != 1 ? 0 : TLSv1_1) |
 					(use_tlsv12 != 1 ? 0 : TLSv1_2) |

src/socket.c

@@ -233,7 +233,6 @@ static int
 init_ssl_ctx( const server_conf_t *conf )
 {
 	server_conf_t *mconf = (server_conf_t *)conf;
-	int options = 0;
 
 	if (conf->SSLContext)
 		return conf->ssl_ctx_valid;
@@ -248,8 +247,7 @@ init_ssl_ctx( const server_conf_t *conf )
 		return 0;
 	}
 
-	if (!(conf->ssl_versions & SSLv3))
-		options |= SSL_OP_NO_SSLv3;
+	int options = SSL_OP_NO_SSLv3;
 	if (!(conf->ssl_versions & TLSv1))
 		options |= SSL_OP_NO_TLSv1;
 #ifdef SSL_OP_NO_TLSv1_1

src/socket.h

@@ -33,7 +33,6 @@
 # include <openssl/ssl.h>
 
 enum {
-	SSLv3 = 2,
 	TLSv1 = 4,
 	TLSv1_1 = 8,
 	TLSv1_2 = 16,