slirp/misc.c

   1 /*
   2  * Copyright (c) 1995 Danny Gasparovski.
   3  *
   4  * Please read the file COPYRIGHT for the
   5  * terms and conditions of the copyright.
   6  */
   7
   8 #include "qemu/osdep.h"
   9 #include "slirp.h"
  10 #include "libslirp.h"
  11 #include "monitor/monitor.h"
  12 #include "qemu/error-report.h"
  13 #include "qemu/main-loop.h"
  14
  15 #ifdef DEBUG
  16 int slirp_debug = DBG_CALL|DBG_MISC|DBG_ERROR;
  17 #endif
  18
  19 inline void
  20 insque(void *a, void *b)
  21 {
  22         register struct quehead *element = (struct quehead *) a;
  23         register struct quehead *head = (struct quehead *) b;
  24         element->qh_link = head->qh_link;
  25         head->qh_link = (struct quehead *)element;
  26         element->qh_rlink = (struct quehead *)head;
  27         ((struct quehead *)(element->qh_link))->qh_rlink
  28         = (struct quehead *)element;
  29 }
  30
  31 inline void
  32 remque(void *a)
  33 {
  34   register struct quehead *element = (struct quehead *) a;
  35   ((struct quehead *)(element->qh_link))->qh_rlink = element->qh_rlink;
  36   ((struct quehead *)(element->qh_rlink))->qh_link = element->qh_link;
  37   element->qh_rlink = NULL;
  38 }
  39
  40 int add_exec(struct ex_list **ex_ptr, int do_pty, char *exec,
  41              struct in_addr addr, int port)
  42 {
  43         struct ex_list *tmp_ptr;
  44
  45         /* First, check if the port is "bound" */
  46         for (tmp_ptr = *ex_ptr; tmp_ptr; tmp_ptr = tmp_ptr->ex_next) {
  47                 if (port == tmp_ptr->ex_fport &&
  48                     addr.s_addr == tmp_ptr->ex_addr.s_addr)
  49                         return -1;
  50         }
  51
  52         tmp_ptr = *ex_ptr;
  53         *ex_ptr = g_new(struct ex_list, 1);
  54         (*ex_ptr)->ex_fport = port;
  55         (*ex_ptr)->ex_addr = addr;
  56         (*ex_ptr)->ex_pty = do_pty;
  57         (*ex_ptr)->ex_exec = (do_pty == 3) ? exec : g_strdup(exec);
  58         (*ex_ptr)->ex_next = tmp_ptr;
  59         return 0;
  60 }
  61
  62
  63 #ifdef _WIN32
  64
  65 int
  66 fork_exec(struct socket *so, const char *ex, int do_pty)
  67 {
  68     /* not implemented */
  69     return 0;
  70 }
  71
  72 #else
  73
  74 /*
  75  * XXX This is ugly
  76  * We create and bind a socket, then fork off to another
  77  * process, which connects to this socket, after which we
  78  * exec the wanted program.  If something (strange) happens,
  79  * the accept() call could block us forever.
  80  *
  81  * do_pty = 0   Fork/exec inetd style
  82  * do_pty = 1   Fork/exec using slirp.telnetd
  83  * do_ptr = 2   Fork/exec using pty
  84  */
  85 int
  86 fork_exec(struct socket *so, const char *ex, int do_pty)
  87 {
  88         int s, cs;
  89         struct sockaddr_in addr, csaddr;
  90         socklen_t addrlen = sizeof(addr);
  91         socklen_t csaddrlen = sizeof(csaddr);
  92         int opt;
  93         const char *argv[256];
  94         /* don't want to clobber the original */
  95         char *bptr;
  96         const char *curarg;
  97         int c, i, ret;
  98         pid_t pid;
  99
 100         DEBUG_CALL("fork_exec");
 101         DEBUG_ARG("so = %p", so);
 102         DEBUG_ARG("ex = %p", ex);
 103         DEBUG_ARG("do_pty = %x", do_pty);
 104
 105         if (do_pty == 2) {
 106                 return 0;
 107         } else {
 108                 addr.sin_family = AF_INET;
 109                 addr.sin_port = 0;
 110                 addr.sin_addr.s_addr = INADDR_ANY;
 111
 112                 if ((s = qemu_socket(AF_INET, SOCK_STREAM, 0)) < 0 ||
 113                     bind(s, (struct sockaddr *)&addr, addrlen) < 0 ||
 114                     listen(s, 1) < 0) {
 115                         error_report("Error: inet socket: %s", strerror(errno));
 116                         if (s >= 0) {
 117                             closesocket(s);
 118                         }
 119
 120                         return 0;
 121                 }
 122         }
 123
 124         if (getsockname(s, (struct sockaddr *)&csaddr, &csaddrlen) < 0) {
 125             closesocket(s);
 126             return 0;
 127         }
 128         cs = qemu_socket(AF_INET, SOCK_STREAM, 0);
 129         if (cs < 0) {
 130             closesocket(s);
 131             return 0;
 132         }
 133         csaddr.sin_addr = loopback_addr;
 134         /*
 135          * This connect won't block because we've already listen()ed on
 136          * the server end (even though we won't accept() the connection
 137          * until later on).
 138          */
 139         do {
 140             ret = connect(cs, (struct sockaddr *)&csaddr, csaddrlen);
 141         } while (ret < 0 && errno == EINTR);
 142         if (ret < 0) {
 143             closesocket(s);
 144             closesocket(cs);
 145             return 0;
 146         }
 147
 148         pid = fork();
 149         switch(pid) {
 150          case -1:
 151                 error_report("Error: fork failed: %s", strerror(errno));
 152                 closesocket(cs);
 153                 close(s);
 154                 return 0;
 155
 156          case 0:
 157                 setsid();
 158
 159                 /* Set the DISPLAY */
 160                 close(s);
 161                 dup2(cs, 0);
 162                 dup2(cs, 1);
 163                 dup2(cs, 2);
 164                 for (s = getdtablesize() - 1; s >= 3; s--)
 165                    close(s);
 166
 167                 i = 0;
 168                 bptr = g_strdup(ex); /* No need to free() this */
 169                 if (do_pty == 1) {
 170                         /* Setup "slirp.telnetd -x" */
 171                         argv[i++] = "slirp.telnetd";
 172                         argv[i++] = "-x";
 173                         argv[i++] = bptr;
 174                 } else
 175                    do {
 176                         /* Change the string into argv[] */
 177                         curarg = bptr;
 178                         while (*bptr != ' ' && *bptr != (char)0)
 179                            bptr++;
 180                         c = *bptr;
 181                         *bptr++ = (char)0;
 182                         argv[i++] = g_strdup(curarg);
 183                    } while (c);
 184
 185                 argv[i] = NULL;
 186                 execvp(argv[0], (char **)argv);
 187
 188                 /* Ooops, failed, let's tell the user why */
 189         fprintf(stderr, "Error: execvp of %s failed: %s\n",
 190                 argv[0], strerror(errno));
 191                 close(0); close(1); close(2); /* XXX */
 192                 exit(1);
 193
 194          default:
 195                 qemu_add_child_watch(pid);
 196                 closesocket(cs);
 197                 /*
 198                  * This should never block, because we already connect()ed
 199                  * on the child end before we forked.
 200                  */
 201                 do {
 202                     so->s = accept(s, (struct sockaddr *)&addr, &addrlen);
 203                 } while (so->s < 0 && errno == EINTR);
 204                 closesocket(s);
 205                 socket_set_fast_reuse(so->s);
 206                 opt = 1;
 207                 qemu_setsockopt(so->s, SOL_SOCKET, SO_OOBINLINE, &opt, sizeof(int));
 208                 qemu_set_nonblock(so->s);
 209
 210                 /* Append the telnet options now */
 211                 if (so->so_m != NULL && do_pty == 1)  {
 212                         sbappend(so, so->so_m);
 213                         so->so_m = NULL;
 214                 }
 215
 216                 return 1;
 217         }
 218 }
 219 #endif
 220
 221 void slirp_connection_info(Slirp *slirp, Monitor *mon)
 222 {
 223     const char * const tcpstates[] = {
 224         [TCPS_CLOSED]       = "CLOSED",
 225         [TCPS_LISTEN]       = "LISTEN",
 226         [TCPS_SYN_SENT]     = "SYN_SENT",
 227         [TCPS_SYN_RECEIVED] = "SYN_RCVD",
 228         [TCPS_ESTABLISHED]  = "ESTABLISHED",
 229         [TCPS_CLOSE_WAIT]   = "CLOSE_WAIT",
 230         [TCPS_FIN_WAIT_1]   = "FIN_WAIT_1",
 231         [TCPS_CLOSING]      = "CLOSING",
 232         [TCPS_LAST_ACK]     = "LAST_ACK",
 233         [TCPS_FIN_WAIT_2]   = "FIN_WAIT_2",
 234         [TCPS_TIME_WAIT]    = "TIME_WAIT",
 235     };
 236     struct in_addr dst_addr;
 237     struct sockaddr_in src;
 238     socklen_t src_len;
 239     uint16_t dst_port;
 240     struct socket *so;
 241     const char *state;
 242     char buf[20];
 243
 244     monitor_printf(mon, "  Protocol[State]    FD  Source Address  Port   "
 245                         "Dest. Address  Port RecvQ SendQ\n");
 246
 247     for (so = slirp->tcb.so_next; so != &slirp->tcb; so = so->so_next) {
 248         if (so->so_state & SS_HOSTFWD) {
 249             state = "HOST_FORWARD";
 250         } else if (so->so_tcpcb) {
 251             state = tcpstates[so->so_tcpcb->t_state];
 252         } else {
 253             state = "NONE";
 254         }
 255         if (so->so_state & (SS_HOSTFWD | SS_INCOMING)) {
 256             src_len = sizeof(src);
 257             getsockname(so->s, (struct sockaddr *)&src, &src_len);
 258             dst_addr = so->so_laddr;
 259             dst_port = so->so_lport;
 260         } else {
 261             src.sin_addr = so->so_laddr;
 262             src.sin_port = so->so_lport;
 263             dst_addr = so->so_faddr;
 264             dst_port = so->so_fport;
 265         }
 266         snprintf(buf, sizeof(buf), "  TCP[%s]", state);
 267         monitor_printf(mon, "%-19s %3d %15s %5d ", buf, so->s,
 268                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
 269                        ntohs(src.sin_port));
 270         monitor_printf(mon, "%15s %5d %5d %5d\n",
 271                        inet_ntoa(dst_addr), ntohs(dst_port),
 272                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 273     }
 274
 275     for (so = slirp->udb.so_next; so != &slirp->udb; so = so->so_next) {
 276         if (so->so_state & SS_HOSTFWD) {
 277             snprintf(buf, sizeof(buf), "  UDP[HOST_FORWARD]");
 278             src_len = sizeof(src);
 279             getsockname(so->s, (struct sockaddr *)&src, &src_len);
 280             dst_addr = so->so_laddr;
 281             dst_port = so->so_lport;
 282         } else {
 283             snprintf(buf, sizeof(buf), "  UDP[%d sec]",
 284                          (so->so_expire - curtime) / 1000);
 285             src.sin_addr = so->so_laddr;
 286             src.sin_port = so->so_lport;
 287             dst_addr = so->so_faddr;
 288             dst_port = so->so_fport;
 289         }
 290         monitor_printf(mon, "%-19s %3d %15s %5d ", buf, so->s,
 291                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
 292                        ntohs(src.sin_port));
 293         monitor_printf(mon, "%15s %5d %5d %5d\n",
 294                        inet_ntoa(dst_addr), ntohs(dst_port),
 295                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 296     }
 297
 298     for (so = slirp->icmp.so_next; so != &slirp->icmp; so = so->so_next) {
 299         snprintf(buf, sizeof(buf), "  ICMP[%d sec]",
 300                      (so->so_expire - curtime) / 1000);
 301         src.sin_addr = so->so_laddr;
 302         dst_addr = so->so_faddr;
 303         monitor_printf(mon, "%-19s %3d %15s  -    ", buf, so->s,
 304                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*");
 305         monitor_printf(mon, "%15s  -    %5d %5d\n", inet_ntoa(dst_addr),
 306                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 307     }
 308 }