Changeset aceeda6

Timestamp:

01/07/19 10:36:22 (2 years ago)

Author:

Jacob Van Walraven <jcv9@…>

Branches:

develop

Children:

3dc6ed6

Parents:

89ed4a0

git-author:

Jacob Van Walraven <jcv9@…> (12/17/18 11:55:21)

git-committer:

Jacob Van Walraven <jcv9@…> (01/07/19 10:36:22)

Message:

Add some checks to prevent segfaults with dead traces

File:

• lib/format_pcapng.c (modified) (7 diffs)

lib/format_pcapng.c

@@ -226 +226 @@
 
 static inline uint32_t pcapng_get_record_type(const libtrace_packet_t *packet) {
-
         uint32_t *btype = (uint32_t *)packet->header;
+
+        if (DATA(packet->trace) == NULL) {
+                return *btype;
+        }
 
         if (DATA(packet->trace)->byteswapped)
@@ -234 +237 @@
 }
 
-static inline uint32_t pcapng_swap32(libtrace_packet_t *packet, uint32_t value) {
-        if (DATAOUT(packet->trace)->byteswapped) {
+static inline uint32_t pcapng_swap32(libtrace_out_t *libtrace, uint32_t value) {
+        if (DATAOUT(libtrace) == NULL) {
+                return value;
+        }
+
+        if (DATAOUT(libtrace)->byteswapped) {
                 return byteswap32(value);
         } else {
@@ -241 +248 @@
         }
 }
-static inline uint32_t pcapng_swap16(libtrace_packet_t *packet, uint32_t value) {
-        if (DATAOUT(packet->trace)->byteswapped) {
+static inline uint32_t pcapng_swap16(libtrace_out_t *libtrace, uint32_t value) {
+        if (DATAOUT(libtrace) == NULL) {
+                return value;
+        }
+
+        if (DATAOUT(libtrace)->byteswapped) {
                 return byteswap16(value);
         } else {
@@ -250 +261 @@
 static inline uint32_t pcapng_get_blocklen(const libtrace_packet_t *packet) {
         struct pcapng_peeker *hdr = (struct pcapng_peeker *)packet->buffer;
+
+        if (DATA(packet->trace) == NULL) {
+                return hdr->blocklen;
+        }
 
         if (DATA(packet->trace)->byteswapped) {
@@ -671 +686 @@
                                 /* Create section block */
                                 pcapng_sec_t sechdr;
-                                sechdr.blocktype = pcapng_swap32(packet, PCAPNG_SECTION_TYPE);
-                                sechdr.blocklen = pcapng_swap32(packet, 28);
-                                sechdr.ordering = pcapng_swap32(packet, 0x1A2B3C4D);
-                                sechdr.majorversion = pcapng_swap16(packet, 1);
+                                sechdr.blocktype = pcapng_swap32(libtrace, PCAPNG_SECTION_TYPE);
+                                sechdr.blocklen = pcapng_swap32(libtrace, 28);
+                                sechdr.ordering = pcapng_swap32(libtrace, 0x1A2B3C4D);
+                                sechdr.majorversion = pcapng_swap16(libtrace, 1);
                                 sechdr.minorversion = 0;
                                 sechdr.sectionlen = 0xFFFFFFFFFFFFFFFF;
@@ -689 +704 @@
                                 /* Create interface block*/
                                 pcapng_int_t inthdr;
-                                inthdr.blocktype = pcapng_swap32(packet, PCAPNG_INTERFACE_TYPE);
-                                inthdr.blocklen = pcapng_swap32(packet, 20);
-                                inthdr.linktype = pcapng_swap16(packet, libtrace_to_pcap_dlt(linktype));
+                                inthdr.blocktype = pcapng_swap32(libtrace, PCAPNG_INTERFACE_TYPE);
+                                inthdr.blocklen = pcapng_swap32(libtrace, 20);
+                                inthdr.linktype = pcapng_swap16(libtrace, libtrace_to_pcap_dlt(linktype));
                                 inthdr.reserved = 0;
                                 inthdr.snaplen = 0;
@@ -749 +764 @@
 
         /* construct the packet */
-        epkthdr.blocktype = pcapng_swap32(packet, PCAPNG_ENHANCED_PACKET_TYPE);
-        epkthdr.blocklen = pcapng_swap32(packet, blocklen);
-        epkthdr.interfaceid = pcapng_swap32(packet, DATAOUT(libtrace)->nextintid-1);
-        epkthdr.timestamp_high = pcapng_swap32(packet, ts.timehigh);
-        epkthdr.timestamp_low = pcapng_swap32(packet, ts.timelow);
-        epkthdr.wlen = pcapng_swap32(packet, wirelen);
-        epkthdr.caplen = pcapng_swap32(packet, caplen);
+        epkthdr.blocktype = pcapng_swap32(libtrace, PCAPNG_ENHANCED_PACKET_TYPE);
+        epkthdr.blocklen = pcapng_swap32(libtrace, blocklen);
+        epkthdr.interfaceid = pcapng_swap32(libtrace, DATAOUT(libtrace)->nextintid-1);
+        epkthdr.timestamp_high = pcapng_swap32(libtrace, ts.timehigh);
+        epkthdr.timestamp_low = pcapng_swap32(libtrace, ts.timelow);
+        epkthdr.wlen = pcapng_swap32(libtrace, wirelen);
+        epkthdr.caplen = pcapng_swap32(libtrace, caplen);
 
         /* output enhanced packet header */