From: Aron Xu <aron@debian.org>
Date: Mon, 13 Feb 2012 15:38:15 +0800
Subject: verbose numeric port
---
netcat.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 55 insertions(+), 4 deletions(-)
diff --git a/netcat.c b/netcat.c
index baab909..eb3453e 100644
--- a/netcat.c
+++ b/netcat.c
@@ -41,6 +41,7 @@
#include <netinet/tcp.h>
#include <netinet/ip.h>
#include <arpa/telnet.h>
+#include <arpa/inet.h>
#ifndef IPTOS_LOWDELAY
# define IPTOS_LOWDELAY 0x10
@@ -424,6 +425,18 @@ main(int argc, char *argv[])
s = local_listen(host, uport, hints);
if (s < 0)
err(1, NULL);
+
+ char* local;
+ if (family == AF_INET6
+ local = "0.0.0.0";
+ else if (family == AF_INET)
+ local = ":::";
+ else
+ local = "unknown"
+ fprintf(stderr, "Listening on [%s] (family %d, port %d)\n",
+ host ?: local,
+ family,
+ *uport);
/*
* For UDP, we will use recvfrom() initially
* to wait for a caller, then use the regular
@@ -432,16 +445,15 @@ main(int argc, char *argv[])
if (uflag) {
int rv, plen;
char buf[16384];
- struct sockaddr_storage z;
- len = sizeof(z);
+ len = sizeof(cliaddr);
plen = jflag ? 16384 : 2048;
rv = recvfrom(s, buf, plen, MSG_PEEK,
- (struct sockaddr *)&z, &len);
+ (struct sockaddr *)&cliaddr, &len);
if (rv < 0)
err(1, "recvfrom");
- rv = connect(s, (struct sockaddr *)&z, len);
+ rv = connect(s, (struct sockaddr *)&cliaddr, len);
if (rv < 0)
err(1, "connect");
@@ -450,6 +462,45 @@ main(int argc, char *argv[])
len = sizeof(cliaddr);
connfd = accept(s, (struct sockaddr *)&cliaddr,
&len);
+ if(vflag) {
+ /* Don't look up port if -n. */
+ if (nflag)
+ sv = NULL;
+ else
+ sv = getservbyport(ntohs(atoi(uport)),
+ uflag ? "udp" : "tcp");
+
+ if (((struct sockaddr *)&cliaddr)->sa_family == AF_INET) {
+ char dst[INET_ADDRSTRLEN];
+ inet_ntop(((struct sockaddr *)&cliaddr)->sa_family,&(((struct sockaddr_in *)&cliaddr)->sin_addr),dst,INET_ADDRSTRLEN);
+ fprintf(stderr, "Connection from [%s] port %s [%s/%s] accepted (family %d, sport %d)\n",
+ dst,
+ uport,
+ uflag ? "udp" : "tcp",
+ sv ? sv->s_name : "*",
+ ((struct sockaddr *)(&cliaddr))->sa_family,
+ ntohs(((struct sockaddr_in *)&cliaddr)->sin_port));
+ }
+ else if(((struct sockaddr *)&cliaddr)->sa_family == AF_INET6) {
+ char dst[INET6_ADDRSTRLEN];
+ inet_ntop(((struct sockaddr *)&cliaddr)->sa_family,&(((struct sockaddr_in6 *)&cliaddr)->sin6_addr),dst,INET6_ADDRSTRLEN);
+ fprintf(stderr, "Connection from [%s] port %s [%s/%s] accepted (family %d, sport %d)\n",
+ dst,
+ uport,
+ uflag ? "udp" : "tcp",
+ sv ? sv->s_name : "*",
+ ((struct sockaddr *)&cliaddr)->sa_family,
+ ntohs(((struct sockaddr_in6 *)&cliaddr)->sin6_port));
+ }
+ else {
+ fprintf(stderr, "Connection from unknown port %s [%s/%s] accepted (family %d, sport %d)\n",
+ uport,
+ uflag ? "udp" : "tcp",
+ sv ? sv->s_name : "*",
+ ((struct sockaddr *)(&cliaddr))->sa_family,
+ ntohs(((struct sockaddr_in *)&cliaddr)->sin_port));
+ }
+ }
readwrite(connfd);
close(connfd);
}
--
|
