From 7ab9cd23988b48956fcfe171d5828d61285baf40 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Thu, 9 Sep 2021 22:00:44 +0200 Subject: [PATCH] libbb: make bb_lookup_port() abort on bad port names Also, no need to preserve errno function old new delta .rodata 104247 104241 -6 bb_lookup_port 97 83 -14 nc_main 1039 1018 -21 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-41) Total: -41 bytes Signed-off-by: Denys Vlasenko --- libbb/xconnect.c | 20 ++++++-------------- networking/ftpgetput.c | 3 +-- networking/nc.c | 2 +- networking/nc_bloaty.c | 7 ++----- 4 files changed, 10 insertions(+), 22 deletions(-) diff --git a/libbb/xconnect.c b/libbb/xconnect.c index 5dd9cfd28..f1983a68b 100644 --- a/libbb/xconnect.c +++ b/libbb/xconnect.c @@ -115,27 +115,19 @@ void FAST_FUNC xconnect(int s, const struct sockaddr *s_addr, socklen_t addrlen) /* Return port number for a service. * If "port" is a number use it as the port. - * If "port" is a name it is looked up in /etc/services, - * if it isnt found return default_port + * If "port" is a name it is looked up in /etc/services. + * if NULL, return default_port */ -unsigned FAST_FUNC bb_lookup_port(const char *port, const char *protocol, unsigned default_port) +unsigned FAST_FUNC bb_lookup_port(const char *port, const char *protocol, unsigned port_nr) { - unsigned port_nr = default_port; if (port) { - int old_errno; - - /* Since this is a lib function, we're not allowed to reset errno to 0. - * Doing so could break an app that is deferring checking of errno. */ - old_errno = errno; port_nr = bb_strtou(port, NULL, 10); if (errno || port_nr > 65535) { struct servent *tserv = getservbyname(port, protocol); - port_nr = default_port; - if (tserv) - port_nr = ntohs(tserv->s_port); -//FIXME: else: port string was garbage, but we don't report that??? + if (!tserv) + bb_error_msg_and_die("bad port '%s'", port); + port_nr = ntohs(tserv->s_port); } - errno = old_errno; } return (uint16_t)port_nr; } diff --git a/networking/ftpgetput.c b/networking/ftpgetput.c index 30b3dabd1..4c92f34a1 100644 --- a/networking/ftpgetput.c +++ b/networking/ftpgetput.c @@ -290,8 +290,7 @@ static const char ftpgetput_longopts[] ALIGN1 = int ftpgetput_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int ftpgetput_main(int argc UNUSED_PARAM, char **argv) { - const char *port = "ftp"; - /* socket to ftp server */ + const char *port = NULL; #if ENABLE_FTPPUT && !ENABLE_FTPGET # define ftp_action ftp_send diff --git a/networking/nc.c b/networking/nc.c index 705b7356a..d351bf72a 100644 --- a/networking/nc.c +++ b/networking/nc.c @@ -216,7 +216,7 @@ int nc_main(int argc, char **argv) close(sfd); } else { cfd = create_and_connect_stream_or_die(argv[0], - argv[1] ? bb_lookup_port(argv[1], "tcp", 0) : 0); + bb_lookup_port(argv[1], "tcp", 0)); } } diff --git a/networking/nc_bloaty.c b/networking/nc_bloaty.c index 25b95246f..cfa133eae 100644 --- a/networking/nc_bloaty.c +++ b/networking/nc_bloaty.c @@ -813,8 +813,6 @@ int nc_main(int argc UNUSED_PARAM, char **argv) //if (option_mask32 & OPT_o) /* hexdump log */ if (option_mask32 & OPT_p) { /* local source port */ o_lport = bb_lookup_port(str_p, o_udpmode ? "udp" : "tcp", 0); - if (!o_lport) - bb_error_msg_and_die("bad local port '%s'", str_p); } //if (option_mask32 & OPT_r) /* randomize various things */ //if (option_mask32 & OPT_u) /* use UDP */ @@ -827,9 +825,8 @@ int nc_main(int argc UNUSED_PARAM, char **argv) if (argv[0]) { themaddr = xhost2sockaddr(argv[0], - argv[1] - ? bb_lookup_port(argv[1], o_udpmode ? "udp" : "tcp", 0) - : 0); + bb_lookup_port(argv[1], o_udpmode ? "udp" : "tcp", 0) + ); } /* create & bind network socket */