[network-manager-openvpn] core: don't crash checking whether keys are encrypted (rh #615875)

[Dan Williams <dcbw src gnome org>]

commit 28c66ad4270b3092f8fa870589acee1359ba1889
Author: Dan Williams <dcbw redhat com>
Date:   Tue Jul 20 15:21:25 2010 -0700

    core: don't crash checking whether keys are encrypted (rh #615875)
    
    g_io_channel_read_line() may return NULL strings, so handle that.

 common/utils.c |   14 ++++++++------
 1 files changed, 8 insertions(+), 6 deletions(-)
---
diff --git a/common/utils.c b/common/utils.c
index 09cef38..1c557f7 100644
--- a/common/utils.c
+++ b/common/utils.c
@@ -73,12 +73,14 @@ is_encrypted (const char *filename)
 	if (!pem_chan)
 		return FALSE;
 
-	while (   g_io_channel_read_line (pem_chan, &str, NULL, NULL, NULL) != G_IO_STATUS_EOF
-	       && !encrypted) {
-		if (   !strncmp (str, PROC_TYPE_TAG, strlen (PROC_TYPE_TAG))
-		    || !strncmp (str, PKCS8_TAG, strlen (PKCS8_TAG)))
-			encrypted = TRUE;
-		g_free (str);
+	while (g_io_channel_read_line (pem_chan, &str, NULL, NULL, NULL) != G_IO_STATUS_EOF) {
+		if (str) {
+			if (g_str_has_prefix (str, PROC_TYPE_TAG) || g_str_has_prefix (str, PKCS8_TAG)) {
+				encrypted = TRUE;
+				break;
+			}
+			g_free (str);
+		}
 	}
 
 	g_io_channel_shutdown (pem_chan, FALSE, NULL);