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
  12 #include "monitor/monitor.h"
  13 #include "qemu/error-report.h"
  14 #include "qemu/main-loop.h"
  15
  16 #ifdef DEBUG
  17 int slirp_debug = DBG_CALL|DBG_MISC|DBG_ERROR;
  18 #endif
  19
  20 struct quehead {
  21         struct quehead *qh_link;
  22         struct quehead *qh_rlink;
  23 };
  24
  25 inline void
  26 insque(void *a, void *b)
  27 {
  28         register struct quehead *element = (struct quehead *) a;
  29         register struct quehead *head = (struct quehead *) b;
  30         element->qh_link = head->qh_link;
  31         head->qh_link = (struct quehead *)element;
  32         element->qh_rlink = (struct quehead *)head;
  33         ((struct quehead *)(element->qh_link))->qh_rlink
  34         = (struct quehead *)element;
  35 }
  36
  37 inline void
  38 remque(void *a)
  39 {
  40   register struct quehead *element = (struct quehead *) a;
  41   ((struct quehead *)(element->qh_link))->qh_rlink = element->qh_rlink;
  42   ((struct quehead *)(element->qh_rlink))->qh_link = element->qh_link;
  43   element->qh_rlink = NULL;
  44 }
  45
  46 int add_exec(struct ex_list **ex_ptr, int do_pty, char *exec,
  47              struct in_addr addr, int port)
  48 {
  49         struct ex_list *tmp_ptr;
  50
  51         /* First, check if the port is "bound" */
  52         for (tmp_ptr = *ex_ptr; tmp_ptr; tmp_ptr = tmp_ptr->ex_next) {
  53                 if (port == tmp_ptr->ex_fport &&
  54                     addr.s_addr == tmp_ptr->ex_addr.s_addr)
  55                         return -1;
  56         }
  57
  58         tmp_ptr = *ex_ptr;
  59         *ex_ptr = g_new(struct ex_list, 1);
  60         (*ex_ptr)->ex_fport = port;
  61         (*ex_ptr)->ex_addr = addr;
  62         (*ex_ptr)->ex_pty = do_pty;
  63         (*ex_ptr)->ex_exec = (do_pty == 3) ? exec : g_strdup(exec);
  64         (*ex_ptr)->ex_next = tmp_ptr;
  65         return 0;
  66 }
  67
  68 #ifndef HAVE_STRERROR
  69
  70 /*
  71  * For systems with no strerror
  72  */
  73
  74 extern int sys_nerr;
  75 extern char *sys_errlist[];
  76
  77 char *
  78 strerror(error)
  79         int error;
  80 {
  81         if (error < sys_nerr)
  82            return sys_errlist[error];
  83         else
  84            return "Unknown error.";
  85 }
  86
  87 #endif
  88
  89
  90 #ifdef _WIN32
  91
  92 int
  93 fork_exec(struct socket *so, const char *ex, int do_pty)
  94 {
  95     /* not implemented */
  96     return 0;
  97 }
  98
  99 #else
 100
 101 /*
 102  * XXX This is ugly
 103  * We create and bind a socket, then fork off to another
 104  * process, which connects to this socket, after which we
 105  * exec the wanted program.  If something (strange) happens,
 106  * the accept() call could block us forever.
 107  *
 108  * do_pty = 0   Fork/exec inetd style
 109  * do_pty = 1   Fork/exec using slirp.telnetd
 110  * do_ptr = 2   Fork/exec using pty
 111  */
 112 int
 113 fork_exec(struct socket *so, const char *ex, int do_pty)
 114 {
 115         int s;
 116         struct sockaddr_in addr;
 117         socklen_t addrlen = sizeof(addr);
 118         int opt;
 119         const char *argv[256];
 120         /* don't want to clobber the original */
 121         char *bptr;
 122         const char *curarg;
 123         int c, i, ret;
 124         pid_t pid;
 125
 126         DEBUG_CALL("fork_exec");
 127         DEBUG_ARG("so = %p", so);
 128         DEBUG_ARG("ex = %p", ex);
 129         DEBUG_ARG("do_pty = %x", do_pty);
 130
 131         if (do_pty == 2) {
 132                 return 0;
 133         } else {
 134                 addr.sin_family = AF_INET;
 135                 addr.sin_port = 0;
 136                 addr.sin_addr.s_addr = INADDR_ANY;
 137
 138                 if ((s = qemu_socket(AF_INET, SOCK_STREAM, 0)) < 0 ||
 139                     bind(s, (struct sockaddr *)&addr, addrlen) < 0 ||
 140                     listen(s, 1) < 0) {
 141                         error_report("Error: inet socket: %s", strerror(errno));
 142                         closesocket(s);
 143
 144                         return 0;
 145                 }
 146         }
 147
 148         pid = fork();
 149         switch(pid) {
 150          case -1:
 151                 error_report("Error: fork failed: %s", strerror(errno));
 152                 close(s);
 153                 return 0;
 154
 155          case 0:
 156                 setsid();
 157
 158                 /* Set the DISPLAY */
 159                 getsockname(s, (struct sockaddr *)&addr, &addrlen);
 160                 close(s);
 161                 /*
 162                  * Connect to the socket
 163                  * XXX If any of these fail, we're in trouble!
 164                  */
 165                 s = qemu_socket(AF_INET, SOCK_STREAM, 0);
 166                 addr.sin_addr = loopback_addr;
 167                 do {
 168                     ret = connect(s, (struct sockaddr *)&addr, addrlen);
 169                 } while (ret < 0 && errno == EINTR);
 170
 171                 dup2(s, 0);
 172                 dup2(s, 1);
 173                 dup2(s, 2);
 174                 for (s = getdtablesize() - 1; s >= 3; s--)
 175                    close(s);
 176
 177                 i = 0;
 178                 bptr = g_strdup(ex); /* No need to free() this */
 179                 if (do_pty == 1) {
 180                         /* Setup "slirp.telnetd -x" */
 181                         argv[i++] = "slirp.telnetd";
 182                         argv[i++] = "-x";
 183                         argv[i++] = bptr;
 184                 } else
 185                    do {
 186                         /* Change the string into argv[] */
 187                         curarg = bptr;
 188                         while (*bptr != ' ' && *bptr != (char)0)
 189                            bptr++;
 190                         c = *bptr;
 191                         *bptr++ = (char)0;
 192                         argv[i++] = g_strdup(curarg);
 193                    } while (c);
 194
 195                 argv[i] = NULL;
 196                 execvp(argv[0], (char **)argv);
 197
 198                 /* Ooops, failed, let's tell the user why */
 199         fprintf(stderr, "Error: execvp of %s failed: %s\n",
 200                 argv[0], strerror(errno));
 201                 close(0); close(1); close(2); /* XXX */
 202                 exit(1);
 203
 204          default:
 205                 qemu_add_child_watch(pid);
 206                 /*
 207                  * XXX this could block us...
 208                  * XXX Should set a timer here, and if accept() doesn't
 209                  * return after X seconds, declare it a failure
 210                  * The only reason this will block forever is if socket()
 211                  * of connect() fail in the child process
 212                  */
 213                 do {
 214                     so->s = accept(s, (struct sockaddr *)&addr, &addrlen);
 215                 } while (so->s < 0 && errno == EINTR);
 216                 closesocket(s);
 217                 socket_set_fast_reuse(so->s);
 218                 opt = 1;
 219                 qemu_setsockopt(so->s, SOL_SOCKET, SO_OOBINLINE, &opt, sizeof(int));
 220                 qemu_set_nonblock(so->s);
 221
 222                 /* Append the telnet options now */
 223                 if (so->so_m != NULL && do_pty == 1)  {
 224                         sbappend(so, so->so_m);
 225                         so->so_m = NULL;
 226                 }
 227
 228                 return 1;
 229         }
 230 }
 231 #endif
 232
 233 void slirp_connection_info(Slirp *slirp, Monitor *mon)
 234 {
 235     const char * const tcpstates[] = {
 236         [TCPS_CLOSED]       = "CLOSED",
 237         [TCPS_LISTEN]       = "LISTEN",
 238         [TCPS_SYN_SENT]     = "SYN_SENT",
 239         [TCPS_SYN_RECEIVED] = "SYN_RCVD",
 240         [TCPS_ESTABLISHED]  = "ESTABLISHED",
 241         [TCPS_CLOSE_WAIT]   = "CLOSE_WAIT",
 242         [TCPS_FIN_WAIT_1]   = "FIN_WAIT_1",
 243         [TCPS_CLOSING]      = "CLOSING",
 244         [TCPS_LAST_ACK]     = "LAST_ACK",
 245         [TCPS_FIN_WAIT_2]   = "FIN_WAIT_2",
 246         [TCPS_TIME_WAIT]    = "TIME_WAIT",
 247     };
 248     struct in_addr dst_addr;
 249     struct sockaddr_in src;
 250     socklen_t src_len;
 251     uint16_t dst_port;
 252     struct socket *so;
 253     const char *state;
 254     char buf[20];
 255
 256     monitor_printf(mon, "  Protocol[State]    FD  Source Address  Port   "
 257                         "Dest. Address  Port RecvQ SendQ\n");
 258
 259     for (so = slirp->tcb.so_next; so != &slirp->tcb; so = so->so_next) {
 260         if (so->so_state & SS_HOSTFWD) {
 261             state = "HOST_FORWARD";
 262         } else if (so->so_tcpcb) {
 263             state = tcpstates[so->so_tcpcb->t_state];
 264         } else {
 265             state = "NONE";
 266         }
 267         if (so->so_state & (SS_HOSTFWD | SS_INCOMING)) {
 268             src_len = sizeof(src);
 269             getsockname(so->s, (struct sockaddr *)&src, &src_len);
 270             dst_addr = so->so_laddr;
 271             dst_port = so->so_lport;
 272         } else {
 273             src.sin_addr = so->so_laddr;
 274             src.sin_port = so->so_lport;
 275             dst_addr = so->so_faddr;
 276             dst_port = so->so_fport;
 277         }
 278         snprintf(buf, sizeof(buf), "  TCP[%s]", state);
 279         monitor_printf(mon, "%-19s %3d %15s %5d ", buf, so->s,
 280                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
 281                        ntohs(src.sin_port));
 282         monitor_printf(mon, "%15s %5d %5d %5d\n",
 283                        inet_ntoa(dst_addr), ntohs(dst_port),
 284                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 285     }
 286
 287     for (so = slirp->udb.so_next; so != &slirp->udb; so = so->so_next) {
 288         if (so->so_state & SS_HOSTFWD) {
 289             snprintf(buf, sizeof(buf), "  UDP[HOST_FORWARD]");
 290             src_len = sizeof(src);
 291             getsockname(so->s, (struct sockaddr *)&src, &src_len);
 292             dst_addr = so->so_laddr;
 293             dst_port = so->so_lport;
 294         } else {
 295             snprintf(buf, sizeof(buf), "  UDP[%d sec]",
 296                          (so->so_expire - curtime) / 1000);
 297             src.sin_addr = so->so_laddr;
 298             src.sin_port = so->so_lport;
 299             dst_addr = so->so_faddr;
 300             dst_port = so->so_fport;
 301         }
 302         monitor_printf(mon, "%-19s %3d %15s %5d ", buf, so->s,
 303                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
 304                        ntohs(src.sin_port));
 305         monitor_printf(mon, "%15s %5d %5d %5d\n",
 306                        inet_ntoa(dst_addr), ntohs(dst_port),
 307                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 308     }
 309
 310     for (so = slirp->icmp.so_next; so != &slirp->icmp; so = so->so_next) {
 311         snprintf(buf, sizeof(buf), "  ICMP[%d sec]",
 312                      (so->so_expire - curtime) / 1000);
 313         src.sin_addr = so->so_laddr;
 314         dst_addr = so->so_faddr;
 315         monitor_printf(mon, "%-19s %3d %15s  -    ", buf, so->s,
 316                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*");
 317         monitor_printf(mon, "%15s  -    %5d %5d\n", inet_ntoa(dst_addr),
 318                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 319     }
 320 }