wlantest: Add support for reading pcap files with prism header

wlantest/process.c

@@ -224,3 +224,41 @@ void wlantest_process(struct wlantest *wt, const u8 *data, size_t len)
 	else
 		tx_status(wt, frame, frame_len, !failed);
 }
+
+
+void wlantest_process_prism(struct wlantest *wt, const u8 *data, size_t len)
+{
+	int fcs = 0;
+	const u8 *frame, *fcspos;
+	size_t frame_len;
+	u32 hdrlen;
+
+	wpa_hexdump(MSG_EXCESSIVE, "Process data", data, len);
+
+	if (len < 8)
+		return;
+	hdrlen = WPA_GET_LE32(data + 4);
+
+	if (len < hdrlen) {
+		wpa_printf(MSG_INFO, "Too short frame to include prism "
+			   "header");
+		return;
+	}
+
+	frame = data + hdrlen;
+	frame_len = len - hdrlen;
+	fcs = 1;
+
+	if (fcs && frame_len >= 4) {
+		frame_len -= 4;
+		fcspos = frame + frame_len;
+		if (check_fcs(frame, frame_len, fcspos) < 0) {
+			wpa_printf(MSG_EXCESSIVE, "Drop RX frame with invalid "
+				   "FCS");
+			wt->fcs_error++;
+			return;
+		}
+	}
+
+	rx_frame(wt, frame, frame_len);
+}

wlantest/readpcap.c

@@ -27,6 +27,7 @@ int read_cap_file(struct wlantest *wt, const char *fname)
 	struct pcap_pkthdr *hdr;
 	const u_char *data;
 	int res;
+	int dlt;
 
 	pcap = pcap_open_offline(fname, errbuf);
 	if (pcap == NULL) {
@@ -34,6 +35,14 @@ int read_cap_file(struct wlantest *wt, const char *fname)
 			   fname, errbuf);
 		return -1;
 	}
+	dlt = pcap_datalink(pcap);
+	if (dlt != DLT_IEEE802_11_RADIO && dlt != DLT_PRISM_HEADER) {
+		wpa_printf(MSG_ERROR, "Unsupported pcap datalink type: %d",
+			   dlt);
+		pcap_close(pcap);
+		return -1;
+	}
+	wpa_printf(MSG_DEBUG, "pcap datalink type: %d", dlt);
 
 	for (;;) {
 		res = pcap_next_ex(pcap, &hdr, &data);
@@ -66,7 +75,14 @@ int read_cap_file(struct wlantest *wt, const char *fname)
 			continue;
 		}
 		count++;
-		wlantest_process(wt, data, hdr->caplen);
+		switch (dlt) {
+		case DLT_IEEE802_11_RADIO:
+			wlantest_process(wt, data, hdr->caplen);
+			break;
+		case DLT_PRISM_HEADER:
+			wlantest_process_prism(wt, data, hdr->caplen);
+			break;
+		}
 	}
 
 	pcap_close(pcap);

wlantest/wlantest.h

@@ -154,6 +154,7 @@ void write_pcap_captured(struct wlantest *wt, const u8 *buf, size_t len);
 void write_pcap_decrypted(struct wlantest *wt, const u8 *buf1, size_t len1,
 			  const u8 *buf2, size_t len2);
 void wlantest_process(struct wlantest *wt, const u8 *data, size_t len);
+void wlantest_process_prism(struct wlantest *wt, const u8 *data, size_t len);
 void wlantest_process_wired(struct wlantest *wt, const u8 *data, size_t len);
 u32 crc32(const u8 *frame, size_t frame_len);
 int monitor_init(struct wlantest *wt, const char *ifname);