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-rw-r--r--ipsvd/udpsvd.c221
1 files changed, 221 insertions, 0 deletions
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]);
+}