mirrors/tcpdump
0
0
Fork 0
mirror of https://github.com/the-tcpdump-group/tcpdump.git synced 2024-11-27 12:03:44 +08:00
Code Issues Packages Projects Releases Wiki Activity

NULL/LOOP: Add a bounds check

Browse Source 
Moreover:
Use uint32_t type for family (32-bit integer).
Add and use tstr[].
This commit is contained in:
Francois-Xavier Le Bail 2018-02-12 11:34:28 +01:00
parent 0d35fd46a1
commit 09e85c97c8
1 changed files with 10 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
print-null.c
View File

@ -30,8 +30,11 @@
#include <string.h>
#include "netdissect.h"
#include "extract.h"
#include "af.h"
static const char tstr[] = " [|null]";
/*
* The DLT_NULL packet header is 4 bytes long. It contains a host-byte-order
* 32-bit integer that specifies the family, e.g. AF_INET.
@ -77,13 +80,12 @@ null_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char
{
u_int length = h->len;
u_int caplen = h->caplen;
u_int family;
uint32_t family;
if (caplen < NULL_HDRLEN) {
ND_PRINT("[|null]");
return (NULL_HDRLEN);
}
if (caplen < NULL_HDRLEN)
goto trunc;
ND_TCHECK_4(p);
memcpy((char *)&family, (const char *)p, sizeof(family));
/*
@ -136,6 +138,9 @@ null_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char
ND_DEFAULTPRINT(p, caplen);
}
return (NULL_HDRLEN);
trunc:
ND_PRINT("%s", tstr);
return (NULL_HDRLEN);
}