udpsvd: forgotten 'svn add'
diff --git a/ipsvd/udpsvd.c b/ipsvd/udpsvd.c
new file mode 100644
index 0000000..b3f6082
--- /dev/null
+++ b/ipsvd/udpsvd.c
@@ -0,0 +1,221 @@
+/* Based on ipsvd utilities written by Gerrit Pape <pape@smarden.org>
+ * which are released into public domain by the author.
+ * Homepage: http://smarden.sunsite.dk/ipsvd/
+ *
+ * Copyright (C) 2007 Denis Vlasenko.
+ *
+ * Licensed under GPLv2, see file LICENSE in this tarball for details.
+ */
+
+/* Based on ipsvd ipsvd-0.12.1. This tcpsvd accepts all options
+ * which are supported by one from ipsvd-0.12.1, but not all are
+ * functional. See help text at the end of this file for details.
+ *
+ * Code inside #if 0" is parts of original tcpsvd which are not implemented
+ * for busyboxed version.
+ *
+ * Output of verbose mode matches original (modulo bugs and
+ * unimplemented stuff). Unnatural splitting of IP and PORT
+ * is retained (personally I prefer one-value "IP:PORT" notation -
+ * it is a natural string representation of struct sockaddr_XX).
+ */
+
+#include "busybox.h"
+
+unsigned verbose;
+
+static void sig_term_handler(int sig)
+{
+	if (verbose)
+		printf("udpsvd: info: sigterm received, exit\n");
+	exit(0);
+}
+
+int udpsvd_main(int argc, char **argv);
+int udpsvd_main(int argc, char **argv)
+{
+	const char *instructs;
+	char *str_t, *user;
+	unsigned opt;
+//	unsigned lookuphost = 0;
+//	unsigned paranoid = 0;
+//	unsigned long timeout = 0;
+
+	char *remote_hostname;
+	char *local_hostname;
+	char *remote_ip;
+	char *local_ip;
+	uint16_t local_port, remote_port;
+	union {
+		struct sockaddr sa;
+		struct sockaddr_in sin;
+		USE_FEATURE_IPV6(struct sockaddr_in6 sin6;)
+	} sock_adr;
+	socklen_t sockadr_size;
+	int sock;
+	int wstat;
+	unsigned pid;
+	struct bb_uidgid_t ugid;
+
+	enum {
+		OPT_v = (1 << 0),
+		OPT_u = (1 << 1),
+		OPT_l = (1 << 2),
+		OPT_h = (1 << 3),
+		OPT_p = (1 << 4),
+		OPT_i = (1 << 5),
+		OPT_x = (1 << 6),
+		OPT_t = (1 << 7),
+	};
+
+	opt_complementary = "ph:vv";
+	opt = getopt32(argc, argv, "vu:l:hpi:x:t:",
+			&user, &local_hostname, &instructs, &instructs, &str_t, &verbose);
+	//if (opt & OPT_x) iscdb =1;
+	//if (opt & OPT_t) timeout = xatou(str_t);
+	if (!(opt & OPT_h))
+		remote_hostname = (char *)"";
+	if (opt & OPT_u) {
+		if (!get_uidgid(&ugid, user, 1))
+			bb_error_msg_and_die("unknown user/group: %s", user);
+	}
+	argv += optind;
+	if (!argv[0][0] || LONE_CHAR(argv[0], '0'))
+		argv[0] = (char*)"0.0.0.0";
+
+	setlinebuf(stdout);
+
+	signal(SIGTERM, sig_term_handler);
+	signal(SIGPIPE, SIG_IGN);
+
+	local_port = bb_lookup_port(argv[1], "udp", 0);
+	sock = create_and_bind_dgram_or_die(argv[0], local_port);
+
+	if (opt & OPT_u) { /* drop permissions */
+		xsetgid(ugid.gid);
+		xsetuid(ugid.uid);
+	}
+	bb_sanitize_stdio(); /* fd# 1,2 must be opened */
+	close(0);
+
+	if (verbose) {
+		/* we do it only for ":port" cosmetics... oh well */
+		len_and_sockaddr *lsa = xhost2sockaddr(argv[0], local_port);
+		char *addr = xmalloc_sockaddr2dotted(&lsa->sa, lsa->len);
+		printf("udpsvd: info: listening on %s", addr);
+		free(addr);
+		if (option_mask32 & OPT_u)
+			printf(", uid %u, gid %u",
+				(unsigned)ugid.uid, (unsigned)ugid.gid);
+		puts(", starting");
+	}
+
+ again:
+/*	io[0].fd = s;
+	io[0].events = IOPAUSE_READ;
+	io[0].revents = 0;
+	taia_now(&now);
+	taia_uint(&deadline, 3600);
+	taia_add(&deadline, &now, &deadline);
+	iopause(io, 1, &deadline, &now);
+	if (!(io[0].revents | IOPAUSE_READ))
+		goto again;
+	io[0].revents = 0;
+*/
+	sockadr_size = sizeof(sock_adr);
+	if (recvfrom(sock, NULL, 0, MSG_PEEK, &sock_adr.sa, &sockadr_size) == -1) {
+		bb_perror_msg("recvfrom");
+		goto again;
+	}
+
+	while ((pid = fork()) < 0) {
+		bb_perror_msg("fork failed, sleeping");
+		sleep(5);
+	}
+	if (pid > 0) { /* parent */
+		while (wait_pid(&wstat, pid) == -1)
+			bb_perror_msg("error waiting for child");
+		if (verbose)
+			printf("udpsvd: info: end %u\n", pid);
+		goto again;
+	}
+
+	/* Child */
+
+/*	if (recvfrom(sock, 0, 0, MSG_PEEK, (struct sockaddr *)&sock_adr, &sockadr_size) == -1)
+		drop("unable to read from socket");
+*/
+	remote_ip = xmalloc_sockaddr2dotted_noport(&sock_adr.sa, sockadr_size);
+	remote_port = get_nport(&sock_adr.sa);
+	remote_port = ntohs(remote_port);
+	if (verbose) {
+		printf("udpsvd: info: pid %u from %s\n", pid, remote_ip);
+	}
+	if (opt & OPT_h) {
+		remote_hostname = xmalloc_sockaddr2host(&sock_adr.sa, sizeof(sock_adr));
+		if (!remote_hostname) {
+			bb_error_msg("warning: cannot look up hostname for %s", remote_ip);
+			remote_hostname = (char*)"";
+		}
+	}
+
+#if 0
+	if (instructs) {
+		ac = ipsvd_check(iscdb, &inst, &match, (char*)instructs,
+				remote_ip, remote_hostname.s, timeout);
+		if (ac == -1) discard("unable to check inst", remote_ip);
+		if (ac == IPSVD_ERR) discard("unable to read", (char*)instructs);
+	} else
+		ac = IPSVD_DEFAULT;
+#endif
+
+	if (verbose) {
+#if 0
+		out("udpsvd: info: ");
+		switch(ac) {
+		case IPSVD_DENY: out("deny "); break;
+		case IPSVD_DEFAULT: case IPSVD_INSTRUCT: out("start "); break;
+		case IPSVD_EXEC: out("exec "); break;
+		}
+#endif
+		printf("udpsvd: info: %u %s:%s :%s:%s:%u\n",
+				pid, local_hostname, local_ip,
+				remote_hostname, remote_ip, remote_port);
+#if 0
+		if (instructs) {
+			out(" ");
+			if (iscdb) {
+				out((char*)instructs); out("/");
+			}
+			outfix(match.s);
+			if(inst.s && inst.len && (verbose > 1)) {
+				out(": "); outinst(&inst);
+			}
+		}
+#endif
+	}
+
+#if 0
+	if (ac == IPSVD_DENY) {
+		recv(s, 0, 0, 0);
+		_exit(100);
+	}
+	if (ac == IPSVD_EXEC) {
+		args[0] = "/bin/sh";
+		args[1] = "-c";
+		args[2] = inst.s;
+		args[3] = NULL;
+		run = args;
+	} else run = prog;
+#endif
+
+	xmove_fd(sock, 0);
+	dup2(0, 1);
+
+	signal(SIGTERM, SIG_DFL);
+	signal(SIGPIPE, SIG_DFL);
+	argv += 2;
+
+	BB_EXECVP(argv[0], argv);
+	bb_perror_msg_and_die("exec '%s'", argv[0]);
+}