Add cancellable openconnect_SSL_write(), use it from openconnect_SSL_…

…printf()

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

cstp.c

@@ -111,9 +111,6 @@ static int start_cstp_connection(struct openconnect_info *vpninfo)
 	}
 
  retry:
-	/* We don't cope with nonblocking mode... yet */
-	fcntl(vpninfo->ssl_fd, F_SETFL, fcntl(vpninfo->ssl_fd, F_GETFL) & ~O_NONBLOCK);
-
 	openconnect_SSL_printf(vpninfo, "CONNECT /CSCOSSLC/tunnel HTTP/1.1\r\n");
 	openconnect_SSL_printf(vpninfo, "Host: %s\r\n", vpninfo->hostname);
 	openconnect_SSL_printf(vpninfo, "User-Agent: %s\r\n", vpninfo->useragent);
@@ -131,6 +128,7 @@ static int start_cstp_connection(struct openconnect_info *vpninfo)
 	openconnect_SSL_printf(vpninfo, "\r\nX-DTLS-CipherSuite: %s\r\n\r\n",
 			       vpninfo->dtls_ciphers?:"AES256-SHA:AES128-SHA:DES-CBC3-SHA:DES-CBC-SHA");
 
+	fcntl(vpninfo->ssl_fd, F_SETFL, fcntl(vpninfo->ssl_fd, F_GETFL) & ~O_NONBLOCK);
 	if (openconnect_SSL_gets(vpninfo, buf, 65536) < 0) {
 		vpn_progress(vpninfo, PRG_ERR,
 			     _("Error fetching HTTPS response\n"));

openconnect-internal.h

@@ -279,6 +279,7 @@ int cstp_reconnect(struct openconnect_info *vpninfo);
 int  __attribute__ ((format (printf, 2, 3)))
     openconnect_SSL_printf(struct openconnect_info *vpninfo, const char *fmt, ...);
 int openconnect_SSL_gets(struct openconnect_info *vpninfo, char *buf, size_t len);
+int openconnect_SSL_write(struct openconnect_info *vpninfo, char *buf, size_t len);
 int openconnect_open_https(struct openconnect_info *vpninfo);
 void openconnect_close_https(struct openconnect_info *vpninfo);
 int get_cert_md5_fingerprint(struct openconnect_info *vpninfo, X509 *cert,

ssl.c

@@ -60,6 +60,48 @@
 /* Helper functions for reading/writing lines over SSL.
    We could use cURL for the HTTP stuff, but it's overkill */
 
+int openconnect_SSL_write(struct openconnect_info *vpninfo, char *buf, size_t len)
+{
+	size_t orig_len = len;
+
+	while (len) {
+		int done = SSL_write(vpninfo->https_ssl, buf, len);
+
+		if (done > 0)
+			len -= done;
+		else {
+			int err = SSL_get_error(vpninfo->https_ssl, done);
+			fd_set wr_set, rd_set;
+			int maxfd = vpninfo->ssl_fd;
+
+			FD_ZERO(&wr_set);
+			FD_ZERO(&rd_set);
+
+			if (err == SSL_ERROR_WANT_READ)
+				FD_SET(vpninfo->ssl_fd, &rd_set);
+			else if (err == SSL_ERROR_WANT_WRITE)
+				FD_SET(vpninfo->ssl_fd, &wr_set);
+			else {
+				vpn_progress(vpninfo, PRG_ERR, _("Failed to write to SSL socket"));
+				report_ssl_errors(vpninfo);
+				return -EIO;
+			}
+			if (vpninfo->cancel_fd != -1) {
+				FD_SET(vpninfo->cancel_fd, &rd_set);
+				if (vpninfo->cancel_fd > vpninfo->ssl_fd)
+					maxfd = vpninfo->cancel_fd;
+			}
+			select(maxfd + 1, &rd_set, &wr_set, NULL, NULL);
+			if (vpninfo->cancel_fd != -1 &&
+			    FD_ISSET(vpninfo->cancel_fd, &rd_set)) {
+				vpn_progress(vpninfo, PRG_ERR, _("SSL write cancelled\n"));
+				return -EINTR;
+			}
+		}
+	}
+	return orig_len;
+}
+
 int  __attribute__ ((format (printf, 2, 3)))
     openconnect_SSL_printf(struct openconnect_info *vpninfo, const char *fmt, ...)
 {
@@ -71,7 +113,7 @@ int  __attribute__ ((format (printf, 2, 3)))
 	va_start(args, fmt);
 	vsnprintf(buf, 1023, fmt, args);
 	va_end(args);
-	return SSL_write(vpninfo->https_ssl, buf, strlen(buf));
+	return openconnect_SSL_write(vpninfo, buf, strlen(buf));
 
 }