networking/ssl_client.c

   1 /*
   2  * Copyright (C) 2017 Denys Vlasenko
   3  *
   4  * Licensed under GPLv2, see file LICENSE in this source tree.
   5  */
   6 //config:config SSL_CLIENT
   7 //config:       bool "ssl_client (23 kb)"
   8 //config:       default y
   9 //config:       select TLS
  10 //config:       help
  11 //config:       This tool pipes data to/from a socket, TLS-encrypting it.
  12
  13 //applet:IF_SSL_CLIENT(APPLET(ssl_client, BB_DIR_USR_BIN, BB_SUID_DROP))
  14
  15 //kbuild:lib-$(CONFIG_SSL_CLIENT) += ssl_client.o
  16
  17 //usage:#define ssl_client_trivial_usage
  18 //usage:       "[-e] -s FD [-r FD] [-n SNI]"
  19 //usage:#define ssl_client_full_usage ""
  20
  21 #include "libbb.h"
  22
  23 int ssl_client_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  24 int ssl_client_main(int argc UNUSED_PARAM, char **argv)
  25 {
  26         tls_state_t *tls;
  27         const char *sni = NULL;
  28         int opt;
  29
  30         // INIT_G();
  31
  32         tls = new_tls_state();
  33         opt = getopt32(argv, "es:+r:+n:", &tls->ofd, &tls->ifd, &sni);
  34         if (!(opt & (1<<2))) {
  35                 /* -r N defaults to -s N */
  36                 tls->ifd = tls->ofd;
  37         }
  38
  39         if (!(opt & (3<<1))) {
  40                 if (!argv[1])
  41                         bb_show_usage();
  42                 /* Undocumented debug feature: without -s and -r, takes HOST arg and connects to it */
  43                 //
  44                 // Talk to kernel.org:
  45                 // printf "GET / HTTP/1.1\r\nHost: kernel.org\r\n\r\n" | busybox ssl_client kernel.org
  46                 if (!sni)
  47                         sni = argv[1];
  48                 tls->ifd = tls->ofd = create_and_connect_stream_or_die(argv[1], 443);
  49         }
  50
  51         tls_handshake(tls, sni);
  52
  53         BUILD_BUG_ON(TLSLOOP_EXIT_ON_LOCAL_EOF != 1);
  54         tls_run_copy_loop(tls, /*flags*/ opt & 1);
  55
  56         return EXIT_SUCCESS;
  57 }