From 0e431542e98f70aeb26291c0ada7bff84851dc77 Mon Sep 17 00:00:00 2001
From: Josh Gao <jmgao@google.com>
Date: Mon, 10 Dec 2018 16:57:46 -0800
Subject: nc: add IPv6 support.
---
toys/net/netcat.c | 108 ++++++++++++++++++++++++++++--------------------------
1 file changed, 56 insertions(+), 52 deletions(-)
(limited to 'toys')
diff --git a/toys/net/netcat.c b/toys/net/netcat.c
index aa251b88..d7dd9264 100644
--- a/toys/net/netcat.c
+++ b/toys/net/netcat.c
@@ -7,14 +7,16 @@
* netcat -L zombies
USE_NETCAT(OLDTOY(nc, netcat, TOYFLAG_USR|TOYFLAG_BIN))
-USE_NETCAT(NEWTOY(netcat, USE_NETCAT_LISTEN("^tlL")"w#<1W#<1p#<1>65535q#<1s:f:"USE_NETCAT_LISTEN("[!tlL][!Lw]"), TOYFLAG_BIN))
+USE_NETCAT(NEWTOY(netcat, USE_NETCAT_LISTEN("^tlL")"w#<1W#<1p#<1>65535q#<1s:f:46"USE_NETCAT_LISTEN("[!tlL][!Lw]")"[!46]", TOYFLAG_BIN))
config NETCAT
bool "netcat"
default y
help
- usage: netcat [-u] [-wpq #] [-s addr] {IPADDR PORTNUM|-f FILENAME}
+ usage: netcat [-46] [-u] [-wpq #] [-s addr] {IPADDR PORTNUM|-f FILENAME}
+ -4 Force IPv4
+ -6 Force IPv6
-f Use FILENAME (ala /dev/ttyS0) instead of network
-p Local port number
-q Quit SECONDS after EOF on stdin, even if stdout hasn't closed yet
@@ -66,35 +68,10 @@ static void set_alarm(int seconds)
alarm(seconds);
}
-// Translate x.x.x.x numeric IPv4 address, or else DNS lookup an IPv4 name.
-static void lookup_name(char *name, uint32_t *result)
-{
- struct hostent *hostbyname;
-
- hostbyname = gethostbyname(name); // getaddrinfo
- if (!hostbyname) error_exit("no host '%s'", name);
- *result = *(uint32_t *)*hostbyname->h_addr_list;
-}
-
-// Worry about a fancy lookup later.
-static unsigned short lookup_port(char *str)
-{
- struct servent *se;
- int i = atoi(str);
-
- if (i>0 && i<65536) return SWAP_BE16(i);
-
- se = getservbyname(str, "tcp");
- i = se ? se->s_port : 0;
- endservent();
-
- return i;
-}
-
void netcat_main(void)
{
- struct sockaddr_in *address = (void *)toybuf;
- int sockfd=-1, in1 = 0, in2 = 0, out1 = 1, out2 = 1;
+ int sockfd = -1, in1 = 0, in2 = 0, out1 = 1, out2 = 1;
+ int family = AF_UNSPEC;
pid_t child;
// Addjust idle and quit_delay to miliseconds or -1 for no timeout
@@ -109,30 +86,18 @@ void netcat_main(void)
(!(toys.optflags&(FLAG_l|FLAG_L)) && toys.optc!=2))
help_exit("bad argument count");
+ if (toys.optflags&FLAG_4)
+ family = AF_INET;
+ else if (toys.optflags&FLAG_6)
+ family = AF_INET6;
+
if (TT.f) in1 = out2 = xopen(TT.f, O_RDWR);
else {
// Setup socket
- sockfd = xsocket(AF_INET, SOCK_STREAM, 0);
- setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &out1, sizeof(out1));
-
- address->sin_family = AF_INET;
- if (TT.s || TT.p) {
- address->sin_port = SWAP_BE16(TT.p);
- if (TT.s)
- lookup_name(TT.s, (uint32_t *)&(address->sin_addr));
- if (bind(sockfd, (struct sockaddr *)address, sizeof(*address)))
- perror_exit("bind");
- }
-
- // Dial out
-
if (!(toys.optflags&(FLAG_L|FLAG_l))) {
- // Figure out where to dial out to.
- lookup_name(*toys.optargs, (uint32_t *)&(address->sin_addr));
- address->sin_port = lookup_port(toys.optargs[1]);
-// TODO xconnect
- if (connect(sockfd, (struct sockaddr *)address, sizeof(*address))<0)
- perror_exit("connect");
+ struct addrinfo *addr = xgetaddrinfo(toys.optargs[0], toys.optargs[1],
+ family, SOCK_STREAM, 0, 0);
+ sockfd = xconnect(addr);
// We have a connection. Disarm timeout.
set_alarm(0);
@@ -142,12 +107,51 @@ void netcat_main(void)
pollinate(in1, in2, out1, out2, TT.W, TT.q);
} else {
// Listen for incoming connections
- socklen_t len = sizeof(*address);
+ struct sockaddr* address = (void*)toybuf;
+ socklen_t len = sizeof(struct sockaddr_storage);
+
+ if (TT.s) {
+ char* port = toybuf;
+ struct addrinfo* bind_addr;
+
+ sprintf(port, "%ld", TT.p);
+ bind_addr = xgetaddrinfo(TT.s, port, family, SOCK_STREAM, 0, 0);
+ sockfd = xbind(bind_addr);
+ } else {
+ size_t bind_addrlen;
+
+ address->sa_family = family;
+
+ if (family == AF_INET6) {
+ struct sockaddr_in6* addr_in6 = (void*)address;
+ bind_addrlen = sizeof(*addr_in6);
+ addr_in6->sin6_port = SWAP_BE16(TT.p);
+ addr_in6->sin6_addr = in6addr_any;
+ } else {
+ struct sockaddr_in* addr_in = (void*)address;
+ bind_addrlen = sizeof(*addr_in);
+ addr_in->sin_port = SWAP_BE16(TT.p);
+ addr_in->sin_addr.s_addr = INADDR_ANY;
+ }
+
+ sockfd = xsocket(family, SOCK_STREAM, 0);
+ if (bind(sockfd, address, bind_addrlen))
+ perror_exit("bind");
+ }
if (listen(sockfd, 5)) error_exit("listen");
if (!TT.p) {
- getsockname(sockfd, (struct sockaddr *)address, &len);
- printf("%d\n", SWAP_BE16(address->sin_port));
+ short port_be;
+
+ getsockname(sockfd, address, &len);
+ if (address->sa_family == AF_INET)
+ port_be = ((struct sockaddr_in*)address)->sin_port;
+ else if (address->sa_family == AF_INET6)
+ port_be = ((struct sockaddr_in6*)address)->sin6_port;
+ else
+ perror_exit("getsockname: bad family");
+
+ printf("%d\n", SWAP_BE16(port_be));
fflush(stdout);
// Return immediately if no -p and -Ll has arguments, so wrapper
// script can use port number.
--
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