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 <slirp.h>
   9 #include <libslirp.h>
  10
  11 #include "monitor/monitor.h"
  12 #include "qemu/main-loop.h"
  13
  14 #ifdef DEBUG
  15 int slirp_debug = DBG_CALL|DBG_MISC|DBG_ERROR;
  16 #endif
  17
  18 struct quehead {
  19         struct quehead *qh_link;
  20         struct quehead *qh_rlink;
  21 };
  22
  23 inline void
  24 insque(void *a, void *b)
  25 {
  26         register struct quehead *element = (struct quehead *) a;
  27         register struct quehead *head = (struct quehead *) b;
  28         element->qh_link = head->qh_link;
  29         head->qh_link = (struct quehead *)element;
  30         element->qh_rlink = (struct quehead *)head;
  31         ((struct quehead *)(element->qh_link))->qh_rlink
  32         = (struct quehead *)element;
  33 }
  34
  35 inline void
  36 remque(void *a)
  37 {
  38   register struct quehead *element = (struct quehead *) a;
  39   ((struct quehead *)(element->qh_link))->qh_rlink = element->qh_rlink;
  40   ((struct quehead *)(element->qh_rlink))->qh_link = element->qh_link;
  41   element->qh_rlink = NULL;
  42 }
  43
  44 int add_exec(struct ex_list **ex_ptr, int do_pty, char *exec,
  45              struct in_addr addr, int port)
  46 {
  47         struct ex_list *tmp_ptr;
  48
  49         /* First, check if the port is "bound" */
  50         for (tmp_ptr = *ex_ptr; tmp_ptr; tmp_ptr = tmp_ptr->ex_next) {
  51                 if (port == tmp_ptr->ex_fport &&
  52                     addr.s_addr == tmp_ptr->ex_addr.s_addr)
  53                         return -1;
  54         }
  55
  56         tmp_ptr = *ex_ptr;
  57         *ex_ptr = (struct ex_list *)malloc(sizeof(struct ex_list));
  58         (*ex_ptr)->ex_fport = port;
  59         (*ex_ptr)->ex_addr = addr;
  60         (*ex_ptr)->ex_pty = do_pty;
  61         (*ex_ptr)->ex_exec = (do_pty == 3) ? exec : strdup(exec);
  62         (*ex_ptr)->ex_next = tmp_ptr;
  63         return 0;
  64 }
  65
  66 #ifndef HAVE_STRERROR
  67
  68 /*
  69  * For systems with no strerror
  70  */
  71
  72 extern int sys_nerr;
  73 extern char *sys_errlist[];
  74
  75 char *
  76 strerror(error)
  77         int error;
  78 {
  79         if (error < sys_nerr)
  80            return sys_errlist[error];
  81         else
  82            return "Unknown error.";
  83 }
  84
  85 #endif
  86
  87
  88 #ifdef _WIN32
  89
  90 int
  91 fork_exec(struct socket *so, const char *ex, int do_pty)
  92 {
  93     /* not implemented */
  94     return 0;
  95 }
  96
  97 #else
  98
  99 /*
 100  * XXX This is ugly
 101  * We create and bind a socket, then fork off to another
 102  * process, which connects to this socket, after which we
 103  * exec the wanted program.  If something (strange) happens,
 104  * the accept() call could block us forever.
 105  *
 106  * do_pty = 0   Fork/exec inetd style
 107  * do_pty = 1   Fork/exec using slirp.telnetd
 108  * do_ptr = 2   Fork/exec using pty
 109  */
 110 int
 111 fork_exec(struct socket *so, const char *ex, int do_pty)
 112 {
 113         int s;
 114         struct sockaddr_in addr;
 115         socklen_t addrlen = sizeof(addr);
 116         int opt;
 117         const char *argv[256];
 118         /* don't want to clobber the original */
 119         char *bptr;
 120         const char *curarg;
 121         int c, i, ret;
 122         pid_t pid;
 123
 124         DEBUG_CALL("fork_exec");
 125         DEBUG_ARG("so = %lx", (long)so);
 126         DEBUG_ARG("ex = %lx", (long)ex);
 127         DEBUG_ARG("do_pty = %lx", (long)do_pty);
 128
 129         if (do_pty == 2) {
 130                 return 0;
 131         } else {
 132                 addr.sin_family = AF_INET;
 133                 addr.sin_port = 0;
 134                 addr.sin_addr.s_addr = INADDR_ANY;
 135
 136                 if ((s = qemu_socket(AF_INET, SOCK_STREAM, 0)) < 0 ||
 137                     bind(s, (struct sockaddr *)&addr, addrlen) < 0 ||
 138                     listen(s, 1) < 0) {
 139                         lprint("Error: inet socket: %s\n", strerror(errno));
 140                         closesocket(s);
 141
 142                         return 0;
 143                 }
 144         }
 145
 146         pid = fork();
 147         switch(pid) {
 148          case -1:
 149                 lprint("Error: fork failed: %s\n", strerror(errno));
 150                 close(s);
 151                 return 0;
 152
 153          case 0:
 154                 setsid();
 155
 156                 /* Set the DISPLAY */
 157                 getsockname(s, (struct sockaddr *)&addr, &addrlen);
 158                 close(s);
 159                 /*
 160                  * Connect to the socket
 161                  * XXX If any of these fail, we're in trouble!
 162                  */
 163                 s = qemu_socket(AF_INET, SOCK_STREAM, 0);
 164                 addr.sin_addr = loopback_addr;
 165                 do {
 166                     ret = connect(s, (struct sockaddr *)&addr, addrlen);
 167                 } while (ret < 0 && errno == EINTR);
 168
 169                 dup2(s, 0);
 170                 dup2(s, 1);
 171                 dup2(s, 2);
 172                 for (s = getdtablesize() - 1; s >= 3; s--)
 173                    close(s);
 174
 175                 i = 0;
 176                 bptr = g_strdup(ex); /* No need to free() this */
 177                 if (do_pty == 1) {
 178                         /* Setup "slirp.telnetd -x" */
 179                         argv[i++] = "slirp.telnetd";
 180                         argv[i++] = "-x";
 181                         argv[i++] = bptr;
 182                 } else
 183                    do {
 184                         /* Change the string into argv[] */
 185                         curarg = bptr;
 186                         while (*bptr != ' ' && *bptr != (char)0)
 187                            bptr++;
 188                         c = *bptr;
 189                         *bptr++ = (char)0;
 190                         argv[i++] = strdup(curarg);
 191                    } while (c);
 192
 193                 argv[i] = NULL;
 194                 execvp(argv[0], (char **)argv);
 195
 196                 /* Ooops, failed, let's tell the user why */
 197         fprintf(stderr, "Error: execvp of %s failed: %s\n",
 198                 argv[0], strerror(errno));
 199                 close(0); close(1); close(2); /* XXX */
 200                 exit(1);
 201
 202          default:
 203                 qemu_add_child_watch(pid);
 204                 /*
 205                  * XXX this could block us...
 206                  * XXX Should set a timer here, and if accept() doesn't
 207                  * return after X seconds, declare it a failure
 208                  * The only reason this will block forever is if socket()
 209                  * of connect() fail in the child process
 210                  */
 211                 do {
 212                     so->s = accept(s, (struct sockaddr *)&addr, &addrlen);
 213                 } while (so->s < 0 && errno == EINTR);
 214                 closesocket(s);
 215                 socket_set_fast_reuse(so->s);
 216                 opt = 1;
 217                 qemu_setsockopt(so->s, SOL_SOCKET, SO_OOBINLINE, &opt, sizeof(int));
 218                 qemu_set_nonblock(so->s);
 219
 220                 /* Append the telnet options now */
 221                 if (so->so_m != NULL && do_pty == 1)  {
 222                         sbappend(so, so->so_m);
 223                         so->so_m = NULL;
 224                 }
 225
 226                 return 1;
 227         }
 228 }
 229 #endif
 230
 231 #ifndef HAVE_STRDUP
 232 char *
 233 strdup(str)
 234         const char *str;
 235 {
 236         char *bptr;
 237
 238         bptr = (char *)malloc(strlen(str)+1);
 239         strcpy(bptr, str);
 240
 241         return bptr;
 242 }
 243 #endif
 244
 245 void lprint(const char *format, ...)
 246 {
 247     va_list args;
 248
 249     va_start(args, format);
 250     monitor_vprintf(default_mon, format, args);
 251     va_end(args);
 252 }
 253
 254 void slirp_connection_info(Slirp *slirp, Monitor *mon)
 255 {
 256     const char * const tcpstates[] = {
 257         [TCPS_CLOSED]       = "CLOSED",
 258         [TCPS_LISTEN]       = "LISTEN",
 259         [TCPS_SYN_SENT]     = "SYN_SENT",
 260         [TCPS_SYN_RECEIVED] = "SYN_RCVD",
 261         [TCPS_ESTABLISHED]  = "ESTABLISHED",
 262         [TCPS_CLOSE_WAIT]   = "CLOSE_WAIT",
 263         [TCPS_FIN_WAIT_1]   = "FIN_WAIT_1",
 264         [TCPS_CLOSING]      = "CLOSING",
 265         [TCPS_LAST_ACK]     = "LAST_ACK",
 266         [TCPS_FIN_WAIT_2]   = "FIN_WAIT_2",
 267         [TCPS_TIME_WAIT]    = "TIME_WAIT",
 268     };
 269     struct in_addr dst_addr;
 270     struct sockaddr_in src;
 271     socklen_t src_len;
 272     uint16_t dst_port;
 273     struct socket *so;
 274     const char *state;
 275     char buf[20];
 276
 277     monitor_printf(mon, "  Protocol[State]    FD  Source Address  Port   "
 278                         "Dest. Address  Port RecvQ SendQ\n");
 279
 280     for (so = slirp->tcb.so_next; so != &slirp->tcb; so = so->so_next) {
 281         if (so->so_state & SS_HOSTFWD) {
 282             state = "HOST_FORWARD";
 283         } else if (so->so_tcpcb) {
 284             state = tcpstates[so->so_tcpcb->t_state];
 285         } else {
 286             state = "NONE";
 287         }
 288         if (so->so_state & (SS_HOSTFWD | SS_INCOMING)) {
 289             src_len = sizeof(src);
 290             getsockname(so->s, (struct sockaddr *)&src, &src_len);
 291             dst_addr = so->so_laddr;
 292             dst_port = so->so_lport;
 293         } else {
 294             src.sin_addr = so->so_laddr;
 295             src.sin_port = so->so_lport;
 296             dst_addr = so->so_faddr;
 297             dst_port = so->so_fport;
 298         }
 299         snprintf(buf, sizeof(buf), "  TCP[%s]", state);
 300         monitor_printf(mon, "%-19s %3d %15s %5d ", buf, so->s,
 301                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
 302                        ntohs(src.sin_port));
 303         monitor_printf(mon, "%15s %5d %5d %5d\n",
 304                        inet_ntoa(dst_addr), ntohs(dst_port),
 305                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 306     }
 307
 308     for (so = slirp->udb.so_next; so != &slirp->udb; so = so->so_next) {
 309         if (so->so_state & SS_HOSTFWD) {
 310             snprintf(buf, sizeof(buf), "  UDP[HOST_FORWARD]");
 311             src_len = sizeof(src);
 312             getsockname(so->s, (struct sockaddr *)&src, &src_len);
 313             dst_addr = so->so_laddr;
 314             dst_port = so->so_lport;
 315         } else {
 316             snprintf(buf, sizeof(buf), "  UDP[%d sec]",
 317                          (so->so_expire - curtime) / 1000);
 318             src.sin_addr = so->so_laddr;
 319             src.sin_port = so->so_lport;
 320             dst_addr = so->so_faddr;
 321             dst_port = so->so_fport;
 322         }
 323         monitor_printf(mon, "%-19s %3d %15s %5d ", buf, so->s,
 324                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
 325                        ntohs(src.sin_port));
 326         monitor_printf(mon, "%15s %5d %5d %5d\n",
 327                        inet_ntoa(dst_addr), ntohs(dst_port),
 328                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 329     }
 330
 331     for (so = slirp->icmp.so_next; so != &slirp->icmp; so = so->so_next) {
 332         snprintf(buf, sizeof(buf), "  ICMP[%d sec]",
 333                      (so->so_expire - curtime) / 1000);
 334         src.sin_addr = so->so_laddr;
 335         dst_addr = so->so_faddr;
 336         monitor_printf(mon, "%-19s %3d %15s  -    ", buf, so->s,
 337                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*");
 338         monitor_printf(mon, "%15s  -    %5d %5d\n", inet_ntoa(dst_addr),
 339                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 340     }
 341 }