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authorDaniel Borkmann <dborkman@redhat.com>2013-03-15 10:41:48 +0100
committerDaniel Borkmann <dborkman@redhat.com>2013-03-15 10:41:48 +0100
commit1a9fbac03c684f29cff9ac44875bd9504a89f54e (patch)
tree1b2e40dbe5dc1899ef5b62c4325c9b94c9c450fc /proto_ipv4.c
all: import netsniff-ng 0.5.8-rc0 source
We decided to get rid of the old Git history and start a new one for several reasons: *) Allow / enforce only high-quality commits (which was not the case for many commits in the history), have a policy that is more close to the one from the Linux kernel. With high quality commits, we mean code that is logically split into commits and commit messages that are signed-off and have a proper subject and message body. We do not allow automatic Github merges anymore, since they are total bullshit. However, we will either cherry-pick your patches or pull them manually. *) The old archive was about ~27MB for no particular good reason. This basically derived from the bad decision that also some PDF files where stored there. From this moment onwards, no binary objects are allowed to be stored in this repository anymore. The old archive is not wiped away from the Internet. You will still be able to find it, e.g. on git.cryptoism.org etc. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Diffstat (limited to 'proto_ipv4.c')
-rw-r--r--proto_ipv4.c201
1 files changed, 201 insertions, 0 deletions
diff --git a/proto_ipv4.c b/proto_ipv4.c
new file mode 100644
index 0000000..e11098f
--- /dev/null
+++ b/proto_ipv4.c
@@ -0,0 +1,201 @@
+/*
+ * netsniff-ng - the packet sniffing beast
+ * Copyright (C) 2009, 2010 Daniel Borkmann
+ * Copyright (C) 2012 Christoph Jaeger <christoph@netsniff-ng.org>
+ * Subject to the GPL, version 2.
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <netinet/in.h> /* for ntohs() */
+#include <arpa/inet.h> /* for inet_ntop() */
+
+#include "proto.h"
+#include "protos.h"
+#include "csum.h"
+#include "dissector_eth.h"
+#include "ipv4.h"
+#include "geoip.h"
+#include "pkt_buff.h"
+#include "built_in.h"
+
+#define FRAG_OFF_RESERVED_FLAG(x) ((x) & 0x8000)
+#define FRAG_OFF_NO_FRAGMENT_FLAG(x) ((x) & 0x4000)
+#define FRAG_OFF_MORE_FRAGMENT_FLAG(x) ((x) & 0x2000)
+#define FRAG_OFF_FRAGMENT_OFFSET(x) ((x) & 0x1fff)
+
+/* IP Option Numbers (http://www.iana.org/assignments/ip-parameters) */
+#define IP_OPT_EOOL 0x00
+#define IP_OPT_NOP 0x01
+
+#define IP_OPT_COPIED_FLAG(x) ((x) & 0x80)
+#define IP_OPT_CLASS(x) (((x) & 0x60) >> 5)
+#define IP_OPT_NUMBER(x) ((x) & 0x1F)
+
+static void ipv4(struct pkt_buff *pkt)
+{
+ uint16_t csum, frag_off, h_tot_len;
+ char src_ip[INET_ADDRSTRLEN];
+ char dst_ip[INET_ADDRSTRLEN];
+ struct ipv4hdr *ip = (struct ipv4hdr *) pkt_pull(pkt, sizeof(*ip));
+ uint8_t *opt, *trailer;
+ unsigned int trailer_len = 0;
+ ssize_t opts_len, opt_len;
+ struct sockaddr_in sas, sad;
+ const char *city, *region, *country;
+
+ if (!ip)
+ return;
+
+ frag_off = ntohs(ip->h_frag_off);
+ h_tot_len = ntohs(ip->h_tot_len);
+ csum = calc_csum(ip, ip->h_ihl * 4, 0);
+
+ inet_ntop(AF_INET, &ip->h_saddr, src_ip, sizeof(src_ip));
+ inet_ntop(AF_INET, &ip->h_daddr, dst_ip, sizeof(dst_ip));
+
+ if ((pkt_len(pkt) + sizeof(*ip)) > h_tot_len) {
+ trailer_len = pkt_len(pkt) + sizeof(*ip) - h_tot_len;
+ trailer = pkt->data + h_tot_len + trailer_len;
+ }
+
+ if (trailer_len) {
+ tprintf(" [ Eth trailer ");
+ while (trailer_len--) {
+ tprintf("%x", *(trailer - trailer_len));
+ }
+ tprintf(" ]\n");
+ }
+
+ tprintf(" [ IPv4 ");
+ tprintf("Addr (%s => %s), ", src_ip, dst_ip);
+ tprintf("Proto (%u), ", ip->h_protocol);
+ tprintf("TTL (%u), ", ip->h_ttl);
+ tprintf("TOS (%u), ", ip->h_tos);
+ tprintf("Ver (%u), ", ip->h_version);
+ tprintf("IHL (%u), ", ip->h_ihl);
+ tprintf("Tlen (%u), ", ntohs(ip->h_tot_len));
+ tprintf("ID (%u), ", ntohs(ip->h_id));
+ tprintf("Res (%u), NoFrag (%u), MoreFrag (%u), FragOff (%u), ",
+ FRAG_OFF_RESERVED_FLAG(frag_off) ? 1 : 0,
+ FRAG_OFF_NO_FRAGMENT_FLAG(frag_off) ? 1 : 0,
+ FRAG_OFF_MORE_FRAGMENT_FLAG(frag_off) ? 1 : 0,
+ FRAG_OFF_FRAGMENT_OFFSET(frag_off));
+ tprintf("CSum (0x%.4x) is %s", ntohs(ip->h_check),
+ csum ? colorize_start_full(black, red) "bogus (!)"
+ colorize_end() : "ok");
+ if (csum)
+ tprintf("%s should be 0x%.4x%s", colorize_start_full(black, red),
+ csum_expected(ip->h_check, csum), colorize_end());
+ tprintf(" ]\n");
+
+ memset(&sas, 0, sizeof(sas));
+ sas.sin_family = PF_INET;
+ sas.sin_addr.s_addr = ip->h_saddr;
+
+ memset(&sad, 0, sizeof(sad));
+ sad.sin_family = PF_INET;
+ sad.sin_addr.s_addr = ip->h_daddr;
+
+ if (geoip_working()) {
+ tprintf("\t[ Geo (");
+ if ((country = geoip4_country_name(sas))) {
+ tprintf("%s", country);
+ if ((region = geoip4_region_name(sas)))
+ tprintf(" / %s", region);
+ if ((city = geoip4_city_name(sas)))
+ tprintf(" / %s", city);
+ } else {
+ tprintf("local");
+ }
+ tprintf(" => ");
+ if ((country = geoip4_country_name(sad))) {
+ tprintf("%s", country);
+ if ((region = geoip4_region_name(sad)))
+ tprintf(" / %s", region);
+ if ((city = geoip4_city_name(sad)))
+ tprintf(" / %s", city);
+ } else {
+ tprintf("local");
+ }
+ tprintf(") ]\n");
+ }
+
+ opts_len = max((uint8_t) ip->h_ihl, sizeof(*ip) / sizeof(uint32_t)) *
+ sizeof(uint32_t) - sizeof(*ip);
+
+ for (opt = pkt_pull(pkt, opts_len); opt && opts_len > 0; opt++) {
+ tprintf(" [ Option Copied (%u), Class (%u), Number (%u)",
+ IP_OPT_COPIED_FLAG(*opt) ? 1 : 0, IP_OPT_CLASS(*opt),
+ IP_OPT_NUMBER(*opt));
+
+ switch (*opt) {
+ case IP_OPT_EOOL:
+ case IP_OPT_NOP:
+ tprintf(" ]\n");
+ opts_len--;
+ break;
+ default:
+ /*
+ * Assuming that EOOL and NOP are the only single-byte
+ * options, treat all other options as variable in
+ * length with a minimum of 2.
+ *
+ * TODO: option length might be incorrect in malformed packets,
+ * check and handle that
+ */
+ opt_len = *(++opt);
+ if (opt_len > opts_len) {
+ tprintf(", Len (%zd, invalid) ]\n", opt_len);
+ goto out;
+ } else
+ tprintf(", Len (%zd) ]\n", opt_len);
+ opts_len -= opt_len;
+ tprintf(" [ Data hex ");
+ for (opt_len -= 2; opt_len > 0; opt_len--)
+ tprintf(" %.2x", *(++opt));
+ tprintf(" ]\n");
+ break;
+ }
+ }
+out:
+ /* cut off everything that is not part of IPv4 payload */
+ /* XXX there could still be an Ethernet trailer included or others */
+
+ pkt_trim(pkt, pkt_len(pkt) - min(pkt_len(pkt),
+ (ntohs(ip->h_tot_len) - ip->h_ihl * sizeof(uint32_t))));
+
+ pkt_set_proto(pkt, &eth_lay3, ip->h_protocol);
+}
+
+static void ipv4_less(struct pkt_buff *pkt)
+{
+ char src_ip[INET_ADDRSTRLEN];
+ char dst_ip[INET_ADDRSTRLEN];
+ struct ipv4hdr *ip = (struct ipv4hdr *) pkt_pull(pkt, sizeof(*ip));
+
+ if (!ip)
+ return;
+
+ inet_ntop(AF_INET, &ip->h_saddr, src_ip, sizeof(src_ip));
+ inet_ntop(AF_INET, &ip->h_daddr, dst_ip, sizeof(dst_ip));
+
+ tprintf(" %s/%s Len %u", src_ip, dst_ip,
+ ntohs(ip->h_tot_len));
+
+ /* cut off IP options and everything that is not part of IPv4 payload */
+ pkt_pull(pkt, max((uint8_t) ip->h_ihl, sizeof(*ip) / sizeof(uint32_t))
+ * sizeof(uint32_t) - sizeof(*ip));
+ /* XXX there coul still be an Ethernet trailer included or others */
+#if 0
+ pkt_trim(pkt, pkt_len(pkt) - min(pkt_len(pkt),
+ (ntohs(ip->h_tot_len) - ip->h_ihl * sizeof(uint32_t))));
+#endif
+ pkt_set_proto(pkt, &eth_lay3, ip->h_protocol);
+}
+
+struct protocol ipv4_ops = {
+ .key = 0x0800,
+ .print_full = ipv4,
+ .print_less = ipv4_less,
+};