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.h"
  12
  13 #ifdef DEBUG
  14 int slirp_debug = DBG_CALL|DBG_MISC|DBG_ERROR;
  15 #endif
  16
  17 struct quehead {
  18         struct quehead *qh_link;
  19         struct quehead *qh_rlink;
  20 };
  21
  22 inline void
  23 insque(void *a, void *b)
  24 {
  25         register struct quehead *element = (struct quehead *) a;
  26         register struct quehead *head = (struct quehead *) b;
  27         element->qh_link = head->qh_link;
  28         head->qh_link = (struct quehead *)element;
  29         element->qh_rlink = (struct quehead *)head;
  30         ((struct quehead *)(element->qh_link))->qh_rlink
  31         = (struct quehead *)element;
  32 }
  33
  34 inline void
  35 remque(void *a)
  36 {
  37   register struct quehead *element = (struct quehead *) a;
  38   ((struct quehead *)(element->qh_link))->qh_rlink = element->qh_rlink;
  39   ((struct quehead *)(element->qh_rlink))->qh_link = element->qh_link;
  40   element->qh_rlink = NULL;
  41 }
  42
  43 int add_exec(struct ex_list **ex_ptr, int do_pty, char *exec,
  44              struct in_addr addr, int port)
  45 {
  46         struct ex_list *tmp_ptr;
  47
  48         /* First, check if the port is "bound" */
  49         for (tmp_ptr = *ex_ptr; tmp_ptr; tmp_ptr = tmp_ptr->ex_next) {
  50                 if (port == tmp_ptr->ex_fport &&
  51                     addr.s_addr == tmp_ptr->ex_addr.s_addr)
  52                         return -1;
  53         }
  54
  55         tmp_ptr = *ex_ptr;
  56         *ex_ptr = (struct ex_list *)malloc(sizeof(struct ex_list));
  57         (*ex_ptr)->ex_fport = port;
  58         (*ex_ptr)->ex_addr = addr;
  59         (*ex_ptr)->ex_pty = do_pty;
  60         (*ex_ptr)->ex_exec = (do_pty == 3) ? exec : strdup(exec);
  61         (*ex_ptr)->ex_next = tmp_ptr;
  62         return 0;
  63 }
  64
  65 #ifndef HAVE_STRERROR
  66
  67 /*
  68  * For systems with no strerror
  69  */
  70
  71 extern int sys_nerr;
  72 extern char *sys_errlist[];
  73
  74 char *
  75 strerror(error)
  76         int error;
  77 {
  78         if (error < sys_nerr)
  79            return sys_errlist[error];
  80         else
  81            return "Unknown error.";
  82 }
  83
  84 #endif
  85
  86
  87 #ifdef _WIN32
  88
  89 int
  90 fork_exec(struct socket *so, const char *ex, int do_pty)
  91 {
  92     /* not implemented */
  93     return 0;
  94 }
  95
  96 #else
  97
  98 /*
  99  * XXX This is ugly
 100  * We create and bind a socket, then fork off to another
 101  * process, which connects to this socket, after which we
 102  * exec the wanted program.  If something (strange) happens,
 103  * the accept() call could block us forever.
 104  *
 105  * do_pty = 0   Fork/exec inetd style
 106  * do_pty = 1   Fork/exec using slirp.telnetd
 107  * do_ptr = 2   Fork/exec using pty
 108  */
 109 int
 110 fork_exec(struct socket *so, const char *ex, int do_pty)
 111 {
 112         int s;
 113         struct sockaddr_in addr;
 114         socklen_t addrlen = sizeof(addr);
 115         int opt;
 116         const char *argv[256];
 117         /* don't want to clobber the original */
 118         char *bptr;
 119         const char *curarg;
 120         int c, i, ret;
 121         pid_t pid;
 122
 123         DEBUG_CALL("fork_exec");
 124         DEBUG_ARG("so = %lx", (long)so);
 125         DEBUG_ARG("ex = %lx", (long)ex);
 126         DEBUG_ARG("do_pty = %lx", (long)do_pty);
 127
 128         if (do_pty == 2) {
 129                 return 0;
 130         } else {
 131                 addr.sin_family = AF_INET;
 132                 addr.sin_port = 0;
 133                 addr.sin_addr.s_addr = INADDR_ANY;
 134
 135                 if ((s = qemu_socket(AF_INET, SOCK_STREAM, 0)) < 0 ||
 136                     bind(s, (struct sockaddr *)&addr, addrlen) < 0 ||
 137                     listen(s, 1) < 0) {
 138                         lprint("Error: inet socket: %s\n", strerror(errno));
 139                         closesocket(s);
 140
 141                         return 0;
 142                 }
 143         }
 144
 145         pid = fork();
 146         switch(pid) {
 147          case -1:
 148                 lprint("Error: fork failed: %s\n", strerror(errno));
 149                 close(s);
 150                 return 0;
 151
 152          case 0:
 153                 setsid();
 154
 155                 /* Set the DISPLAY */
 156                 getsockname(s, (struct sockaddr *)&addr, &addrlen);
 157                 close(s);
 158                 /*
 159                  * Connect to the socket
 160                  * XXX If any of these fail, we're in trouble!
 161                  */
 162                 s = qemu_socket(AF_INET, SOCK_STREAM, 0);
 163                 addr.sin_addr = loopback_addr;
 164                 do {
 165                     ret = connect(s, (struct sockaddr *)&addr, addrlen);
 166                 } while (ret < 0 && errno == EINTR);
 167
 168                 dup2(s, 0);
 169                 dup2(s, 1);
 170                 dup2(s, 2);
 171                 for (s = getdtablesize() - 1; s >= 3; s--)
 172                    close(s);
 173
 174                 i = 0;
 175                 bptr = g_strdup(ex); /* No need to free() this */
 176                 if (do_pty == 1) {
 177                         /* Setup "slirp.telnetd -x" */
 178                         argv[i++] = "slirp.telnetd";
 179                         argv[i++] = "-x";
 180                         argv[i++] = bptr;
 181                 } else
 182                    do {
 183                         /* Change the string into argv[] */
 184                         curarg = bptr;
 185                         while (*bptr != ' ' && *bptr != (char)0)
 186                            bptr++;
 187                         c = *bptr;
 188                         *bptr++ = (char)0;
 189                         argv[i++] = strdup(curarg);
 190                    } while (c);
 191
 192                 argv[i] = NULL;
 193                 execvp(argv[0], (char **)argv);
 194
 195                 /* Ooops, failed, let's tell the user why */
 196         fprintf(stderr, "Error: execvp of %s failed: %s\n",
 197                 argv[0], strerror(errno));
 198                 close(0); close(1); close(2); /* XXX */
 199                 exit(1);
 200
 201          default:
 202                 qemu_add_child_watch(pid);
 203                 /*
 204                  * XXX this could block us...
 205                  * XXX Should set a timer here, and if accept() doesn't
 206                  * return after X seconds, declare it a failure
 207                  * The only reason this will block forever is if socket()
 208                  * of connect() fail in the child process
 209                  */
 210                 do {
 211                     so->s = accept(s, (struct sockaddr *)&addr, &addrlen);
 212                 } while (so->s < 0 && errno == EINTR);
 213                 closesocket(s);
 214                 opt = 1;
 215                 setsockopt(so->s, SOL_SOCKET, SO_REUSEADDR, (char *)&opt, sizeof(int));
 216                 opt = 1;
 217                 setsockopt(so->s, SOL_SOCKET, SO_OOBINLINE, (char *)&opt, sizeof(int));
 218                 socket_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 #include "monitor.h"
 246
 247 void lprint(const char *format, ...)
 248 {
 249     va_list args;
 250
 251     va_start(args, format);
 252     monitor_vprintf(default_mon, format, args);
 253     va_end(args);
 254 }
 255
 256 void
 257 u_sleep(int usec)
 258 {
 259         struct timeval t;
 260         fd_set fdset;
 261
 262         FD_ZERO(&fdset);
 263
 264         t.tv_sec = 0;
 265         t.tv_usec = usec * 1000;
 266
 267         select(0, &fdset, &fdset, &fdset, &t);
 268 }
 269
 270 void slirp_connection_info(Slirp *slirp, Monitor *mon)
 271 {
 272     const char * const tcpstates[] = {
 273         [TCPS_CLOSED]       = "CLOSED",
 274         [TCPS_LISTEN]       = "LISTEN",
 275         [TCPS_SYN_SENT]     = "SYN_SENT",
 276         [TCPS_SYN_RECEIVED] = "SYN_RCVD",
 277         [TCPS_ESTABLISHED]  = "ESTABLISHED",
 278         [TCPS_CLOSE_WAIT]   = "CLOSE_WAIT",
 279         [TCPS_FIN_WAIT_1]   = "FIN_WAIT_1",
 280         [TCPS_CLOSING]      = "CLOSING",
 281         [TCPS_LAST_ACK]     = "LAST_ACK",
 282         [TCPS_FIN_WAIT_2]   = "FIN_WAIT_2",
 283         [TCPS_TIME_WAIT]    = "TIME_WAIT",
 284     };
 285     struct in_addr dst_addr;
 286     struct sockaddr_in src;
 287     socklen_t src_len;
 288     uint16_t dst_port;
 289     struct socket *so;
 290     const char *state;
 291     char buf[20];
 292
 293     monitor_printf(mon, "  Protocol[State]    FD  Source Address  Port   "
 294                         "Dest. Address  Port RecvQ SendQ\n");
 295
 296     for (so = slirp->tcb.so_next; so != &slirp->tcb; so = so->so_next) {
 297         if (so->so_state & SS_HOSTFWD) {
 298             state = "HOST_FORWARD";
 299         } else if (so->so_tcpcb) {
 300             state = tcpstates[so->so_tcpcb->t_state];
 301         } else {
 302             state = "NONE";
 303         }
 304         if (so->so_state & (SS_HOSTFWD | SS_INCOMING)) {
 305             src_len = sizeof(src);
 306             getsockname(so->s, (struct sockaddr *)&src, &src_len);
 307             dst_addr = so->so_laddr;
 308             dst_port = so->so_lport;
 309         } else {
 310             src.sin_addr = so->so_laddr;
 311             src.sin_port = so->so_lport;
 312             dst_addr = so->so_faddr;
 313             dst_port = so->so_fport;
 314         }
 315         snprintf(buf, sizeof(buf), "  TCP[%s]", state);
 316         monitor_printf(mon, "%-19s %3d %15s %5d ", buf, so->s,
 317                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
 318                        ntohs(src.sin_port));
 319         monitor_printf(mon, "%15s %5d %5d %5d\n",
 320                        inet_ntoa(dst_addr), ntohs(dst_port),
 321                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 322     }
 323
 324     for (so = slirp->udb.so_next; so != &slirp->udb; so = so->so_next) {
 325         if (so->so_state & SS_HOSTFWD) {
 326             snprintf(buf, sizeof(buf), "  UDP[HOST_FORWARD]");
 327             src_len = sizeof(src);
 328             getsockname(so->s, (struct sockaddr *)&src, &src_len);
 329             dst_addr = so->so_laddr;
 330             dst_port = so->so_lport;
 331         } else {
 332             snprintf(buf, sizeof(buf), "  UDP[%d sec]",
 333                          (so->so_expire - curtime) / 1000);
 334             src.sin_addr = so->so_laddr;
 335             src.sin_port = so->so_lport;
 336             dst_addr = so->so_faddr;
 337             dst_port = so->so_fport;
 338         }
 339         monitor_printf(mon, "%-19s %3d %15s %5d ", buf, so->s,
 340                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
 341                        ntohs(src.sin_port));
 342         monitor_printf(mon, "%15s %5d %5d %5d\n",
 343                        inet_ntoa(dst_addr), ntohs(dst_port),
 344                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 345     }
 346
 347     for (so = slirp->icmp.so_next; so != &slirp->icmp; so = so->so_next) {
 348         snprintf(buf, sizeof(buf), "  ICMP[%d sec]",
 349                      (so->so_expire - curtime) / 1000);
 350         src.sin_addr = so->so_laddr;
 351         dst_addr = so->so_faddr;
 352         monitor_printf(mon, "%-19s %3d %15s  -    ", buf, so->s,
 353                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*");
 354         monitor_printf(mon, "%15s  -    %5d %5d\n", inet_ntoa(dst_addr),
 355                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
 356     }
 357 }