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