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| author | Francois-Xavier Le Bail <devel.fx.lebail@orange.fr> | 2018-02-12 11:34:28 +0100 |
|---|---|---|
| committer | Francois-Xavier Le Bail <devel.fx.lebail@orange.fr> | 2018-02-12 11:37:50 +0100 |
| commit | 09e85c97c83e87fd5cb0510b351b9d3fe328de78 (patch) | |
| tree | 97e6655908da9baa2019bd04a4cf81a411236210 /print-null.c | |
| parent | 0d35fd46a18909afce7dd9cf8041165d769e97d4 (diff) | |
| download | tcpdump-09e85c97c83e87fd5cb0510b351b9d3fe328de78.tar.gz | |
NULL/LOOP: Add a bounds check
Moreover:
Use uint32_t type for family (32-bit integer).
Add and use tstr[].
Diffstat (limited to 'print-null.c')
| -rw-r--r-- | print-null.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/print-null.c b/print-null.c index 874521e2..f1067ff5 100644 --- a/print-null.c +++ b/print-null.c @@ -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)); /* @@ -137,6 +139,9 @@ null_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char } return (NULL_HDRLEN); +trunc: + ND_PRINT("%s", tstr); + return (NULL_HDRLEN); } /* |