From: Guy Harris <guy@alum.mit.edu>
Date: Wed, 3 Jul 2019 20:54:36 +0000 (-0700)
Subject: Report PCAP_ERROR_NO_SUCH_DEVICE for a non-existent device.
X-Git-Tag: libpcap-1.10-bp~472
X-Git-Url: https://git.tcpdump.org/libpcap/commitdiff_plain/7850af83ae9119f35ed56e4e29dabb3a78e2e485?ds=sidebyside

Report PCAP_ERROR_NO_SUCH_DEVICE for a non-existent device.
---

diff --git a/pcap-npf.c b/pcap-npf.c
index 15018da9..09969f3d 100644
--- a/pcap-npf.c
+++ b/pcap-npf.c
@@ -938,14 +938,28 @@ pcap_activate_npf(pcap_t *p)
 
 	if (pw->adapter == NULL)
 	{
-		/* Adapter detected but we are not able to open it. Return failure. */
-		pcap_fmt_errmsg_for_win32_err(p->errbuf, PCAP_ERRBUF_SIZE,
-		    GetLastError(), "Error opening adapter");
-		if (pw->rfmon_selfstart)
-		{
-			PacketSetMonitorMode(p->opt.device, 0);
+		DWORD errcode = GetLastError();
+
+		/*
+		 * What error did we get when trying to open the adapter?
+		 */
+		if (errcode == ERROR_BAD_UNIT) {
+			/*
+			 * There's no such device.
+			 */
+			return (PCAP_ERROR_NO_SUCH_DEVICE);
+		} else {
+			/*
+			 * Unknown - report details.
+			 */
+			pcap_fmt_errmsg_for_win32_err(p->errbuf, PCAP_ERRBUF_SIZE,
+			    errcode, "Error opening adapter");
+			if (pw->rfmon_selfstart)
+			{
+				PacketSetMonitorMode(p->opt.device, 0);
+			}
+			return (PCAP_ERROR);
 		}
-		return (PCAP_ERROR);
 	}
 
 	/*get network type*/