static void
pkt_handler_en10mb(u_char *usr, const struct pcap_pkthdr *pkt,
const u_char *d)
{
struct machdr *mac = mac_hdr(d);
sb_reset(&sb);
eth_print(mac, &sb);
sb_append_str(&sb, "; ");
etherframe_print(usr, pkt, d + ETH_HLEN, mac->type);
fprintf(stdout, "pkt: %s\n", sb.buf);
}
int iphdr_print(struct iphdr *iph, struct strbuf *sb)
{
const char *s;
int len;
char ihl[16];
char flags[10];
if (iph->version == 6) {
const char msg[] = "IPv6 headers are not yet supported";
size_t msglen = sizeof(msg);
if (sb_room(sb) < msglen)
return -ENOBUFS;;
sb_append_str(sb, msg);
return 0;
}
len = sprintf(ihl, "hdrlen: %d ", iph->ihl * 4);
len += sprintf(flags, "[DF%dMF%d] ", ip_df(iph), ip_mf(iph));
if (sb_room(sb) < (INET_ADDRSTRLEN * 2) + 3 + len)
return -ENOBUFS;
sb_append_str(sb, ihl);
sb->len += sprintf(sb_curr(sb), "tot: %u ", ntohs(iph->tot_len));
sb_append_str(sb, flags);
s = inet_ntop(AF_INET, &iph->saddr, sb_curr(sb), INET_ADDRSTRLEN);
if (!s)
return -errno;
sb->len += strlen(s);
sb_append_str(sb, "->");
s = inet_ntop(AF_INET, &iph->daddr, sb_curr(sb), INET_ADDRSTRLEN);
if (!s)
return -errno;
sb->len += strlen(s);
return 0;
}
/**
* Appends the formatted string to the given string builder
*/
void sb_append_strf(stringbuilder* sb, const char* fmt, ...) {
char *str;
va_list arglist;
va_start(arglist, fmt);
xp_vasprintf(&str, fmt, arglist);
va_end(arglist);
if (!str) {
return;
}
sb_append_str(sb, str);
free(str);
}
/**
* Breaks up the input into multiple quoted lines, making sure each line doesn't go over the 80 column
* limit. This is for aesthetic reasons as well as because there are compilers that can't tolerate
* incredibly long source lines
*/
static void _breakup_lines_modifier_cb(const char* name, const char* args, const char* marker, const char* value, stringbuilder* out_sb) {
char* p;
p = (char*)value;
int i;
i = 0;
while(*p) {
sb_append_ch(out_sb, *p++);
// Attempt to keep everything under 80 cols by splitting up lines
if (i++ > 70 && *p && *(p-1) != '\\') {
i = 0;
sb_append_str(out_sb, "\"\n \"");
}
}
sb_append_ch(out_sb, '\0');
}
static void etherframe_print(u_char *usr, const struct pcap_pkthdr *pkt,
const u_char *d, uint16_t ethtype)
{
struct iphdr *ip;
struct tcphdr *th;
struct udphdr *uh;
uint16_t ethtype_le;
ethtype_le = ntohs(ethtype);
switch (ethtype_le) {
case ETH_P_IP:
ip = ip_hdr(d);
sb_append_str(&sb, "IP: ");
iphdr_print(ip, &sb);
switch (ip->protocol) {
case IPPROTO_TCP:
th = tcp_hdr(d + ip_hdrlen(ip));
sb_append_str(&sb, "; TCP: ");
tcp_print(th, &sb);
break;
case IPPROTO_UDP:
uh = udp_hdr(d + ip_hdrlen(ip));
sb_append_str(&sb, "; UDP: ");
udp_print(uh, &sb);
break;
default:
sb_append_char(&sb, ' ');
sb_append_str(&sb, ipproto_str(ip->protocol));
}
break;
default:
/* FIXME: This code is open to buffer overrun errors */
sb_append_str(&sb, "ether type: ");
sb.len += sprintf(sb_curr(&sb), "0x%04x ", ethtype_le);
sb_append_str(&sb, ethertype_to_str(ethtype_le));
}
}
