winsup/cygwin/libc/rexec.cc

   1 /*
   2  * Copyright (c) 1980, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * $FreeBSD$
  30  */
  31
  32 /* CV 2006-07-04: Tweaked for inclusion into Cygwin. */
  33
  34 #if defined(LIBC_SCCS) && !defined(lint)
  35 static char sccsid[] = "@(#)rexec.c     8.1 (Berkeley) 6/4/93";
  36 #endif /* LIBC_SCCS and not lint */
  37
  38 #ifdef __CYGWIN__
  39 #include "winsup.h"
  40 #include "sigproc.h"
  41 #include "cygtls.h"
  42 #include <wininet.h>
  43 #endif
  44
  45 #include <sys/types.h>
  46 #include <sys/uio.h>
  47 #include <sys/socket.h>
  48 #include <sys/param.h>
  49 #include <sys/stat.h>
  50
  51 #include <netinet/in.h>
  52
  53 #include <stdio.h>
  54 #include <unistd.h>
  55 #include <string.h>
  56 #include <netdb.h>
  57 #include <errno.h>
  58 #include <ctype.h>
  59 #include <err.h>
  60 #include <stdlib.h>
  61 #include <unistd.h>
  62
  63 extern "C" {
  64   int cygwin_accept (int, struct sockaddr *, socklen_t *);
  65   int cygwin_connect (int, const struct sockaddr *, socklen_t);
  66   int cygwin_getsockname (int, struct sockaddr *, socklen_t *);
  67   void cygwin_herror (const char *);
  68   int cygwin_listen (int, int);
  69   int cygwin_socket (int, int, int);
  70 }
  71
  72 /*
  73  * Options and other state info.
  74  */
  75 struct macel {
  76         char mac_name[9];       /* macro name */
  77         char *mac_start;        /* start of macro in macbuf */
  78         char *mac_end;          /* end of macro in macbuf */
  79 };
  80
  81 int macnum;                     /* number of defined macros */
  82 struct macel macros[16];
  83 char macbuf[4096];
  84
  85 static  FILE *cfile;
  86
  87 #define DEFAULT 1
  88 #define LOGIN   2
  89 #define PASSWD  3
  90 #define ACCOUNT 4
  91 #define MACDEF  5
  92 #define ID      10
  93 #define MACH    11
  94
  95 static char tokval[100];
  96
  97 static struct toktab {
  98         const char *tokstr;
  99         int tval;
 100 } toktab[]= {
 101         { "default",    DEFAULT },
 102         { "login",      LOGIN },
 103         { "password",   PASSWD },
 104         { "passwd",     PASSWD },
 105         { "account",    ACCOUNT },
 106         { "machine",    MACH },
 107         { "macdef",     MACDEF },
 108         { NULL,         0 }
 109 };
 110
 111 static int
 112 token()
 113 {
 114         char *cp;
 115         int c;
 116         struct toktab *t;
 117
 118         if (feof(cfile) || ferror(cfile))
 119                 return (0);
 120         while ((c = getc(cfile)) != EOF &&
 121             (c == '\n' || c == '\t' || c == ' ' || c == ','))
 122                 continue;
 123         if (c == EOF)
 124                 return (0);
 125         cp = tokval;
 126         if (c == '"') {
 127                 while ((c = getc(cfile)) != EOF && c != '"') {
 128                         if (c == '\\')
 129                                 c = getc(cfile);
 130                         *cp++ = c;
 131                 }
 132         } else {
 133                 *cp++ = c;
 134                 while ((c = getc(cfile)) != EOF
 135                     && c != '\n' && c != '\t' && c != ' ' && c != ',') {
 136                         if (c == '\\')
 137                                 c = getc(cfile);
 138                         *cp++ = c;
 139                 }
 140         }
 141         *cp = 0;
 142         if (tokval[0] == 0)
 143                 return (0);
 144         for (t = toktab; t->tokstr; t++)
 145                 if (!strcmp(t->tokstr, tokval))
 146                         return (t->tval);
 147         return (ID);
 148 }
 149
 150 static int
 151 ruserpass(const char *host, char **aname, char **apass, char **aacct)
 152 {
 153         const char *hdir;
 154         char buf[BUFSIZ], *tmp;
 155         char myname[INTERNET_MAX_HOST_NAME_LENGTH + 1];
 156         const char *mydomain;
 157         int t, i, c, usedefault = 0;
 158         struct stat stb;
 159
 160         hdir = getenv("HOME");
 161         if (hdir == NULL)
 162                 hdir = ".";
 163         if (strlen(hdir) + 8 > sizeof(buf))
 164                 return (0);
 165         (void) sprintf(buf, "%s/.netrc", hdir);
 166         cfile = fopen(buf, "r");
 167         if (cfile == NULL) {
 168                 if (errno != ENOENT)
 169                         warn("%s", buf);
 170                 return (0);
 171         }
 172         if (cygwin_gethostname(myname, sizeof(myname)) < 0)
 173                 myname[0] = '\0';
 174         if ((mydomain = strchr(myname, '.')) == NULL)
 175                 mydomain = "";
 176 next:
 177         while ((t = token())) switch(t) {
 178
 179         case DEFAULT:
 180                 usedefault = 1;
 181                 /* FALL THROUGH */
 182
 183         case MACH:
 184                 if (!usedefault) {
 185                         if (token() != ID)
 186                                 continue;
 187                         /*
 188                          * Allow match either for user's input host name
 189                          * or official hostname.  Also allow match of
 190                          * incompletely-specified host in local domain.
 191                          */
 192                         if (strcasecmp(host, tokval) == 0)
 193                                 goto match;
 194                         if ((tmp = strchr(host, '.')) != NULL &&
 195                             strcasecmp(tmp, mydomain) == 0 &&
 196                             strncasecmp(host, tokval, tmp - host) == 0 &&
 197                             tokval[tmp - host] == '\0')
 198                                 goto match;
 199                         continue;
 200                 }
 201         match:
 202                 while ((t = token()) && t != MACH && t != DEFAULT) switch(t) {
 203
 204                 case LOGIN:
 205                         if (token()) {
 206                                 if (*aname == 0) {
 207                                         *aname = (char *) malloc((unsigned) strlen(tokval) + 1);
 208                                         (void) strcpy(*aname, tokval);
 209                                 } else {
 210                                         if (strcmp(*aname, tokval))
 211                                                 goto next;
 212                                 }
 213                         }
 214                         break;
 215                 case PASSWD:
 216                         if ((*aname == 0 || strcmp(*aname, "anonymous")) &&
 217                             fstat64(fileno(cfile), &stb) >= 0 &&
 218                             (stb.st_mode & 077) != 0) {
 219         warnx("Error: .netrc file is readable by others.");
 220         warnx("Remove password or make file unreadable by others.");
 221                                 goto bad;
 222                         }
 223                         if (token() && *apass == 0) {
 224                                 *apass = (char *) malloc((unsigned) strlen(tokval) + 1);
 225                                 (void) strcpy(*apass, tokval);
 226                         }
 227                         break;
 228                 case ACCOUNT:
 229                         if (fstat64(fileno(cfile), &stb) >= 0
 230                             && (stb.st_mode & 077) != 0) {
 231         warnx("Error: .netrc file is readable by others.");
 232         warnx("Remove account or make file unreadable by others.");
 233                                 goto bad;
 234                         }
 235                         if (token() && aacct && *aacct == 0) {
 236                                 *aacct = (char *) malloc((unsigned) strlen(tokval) + 1);
 237                                 (void) strcpy(*aacct, tokval);
 238                         }
 239                         break;
 240                 case MACDEF:
 241                         while ((c=getc(cfile)) != EOF &&
 242                                                 (c == ' ' || c == '\t'))
 243                                 ;
 244                         if (c == EOF || c == '\n') {
 245                                 printf("Missing macdef name argument.\n");
 246                                 goto bad;
 247                         }
 248                         if (macnum == 16) {
 249                                 printf("Limit of 16 macros have already been defined\n");
 250                                 goto bad;
 251                         }
 252                         tmp = macros[macnum].mac_name;
 253                         *tmp++ = c;
 254                         for (i=0; i < 8 && (c=getc(cfile)) != EOF &&
 255                             !isspace(c); ++i) {
 256                                 *tmp++ = c;
 257                         }
 258                         if (c == EOF) {
 259                                 printf("Macro definition missing null line terminator.\n");
 260                                 goto bad;
 261                         }
 262                         *tmp = '\0';
 263                         if (c != '\n') {
 264                                 while ((c=getc(cfile)) != EOF && c != '\n');
 265                         }
 266                         if (c == EOF) {
 267                                 printf("Macro definition missing null line terminator.\n");
 268                                 goto bad;
 269                         }
 270                         if (macnum == 0) {
 271                                 macros[macnum].mac_start = macbuf;
 272                         }
 273                         else {
 274                                 macros[macnum].mac_start = macros[macnum-1].mac_end + 1;
 275                         }
 276                         tmp = macros[macnum].mac_start;
 277                         while (tmp != macbuf + 4096) {
 278                                 if ((c=getc(cfile)) == EOF) {
 279                                 printf("Macro definition missing null line terminator.\n");
 280                                         goto bad;
 281                                 }
 282                                 *tmp = c;
 283                                 if (*tmp == '\n') {
 284                                         if (*(tmp-1) == '\0') {
 285                                            macros[macnum++].mac_end = tmp - 1;
 286                                            break;
 287                                         }
 288                                         *tmp = '\0';
 289                                 }
 290                                 tmp++;
 291                         }
 292                         if (tmp == macbuf + 4096) {
 293                                 printf("4K macro buffer exceeded\n");
 294                                 goto bad;
 295                         }
 296                         break;
 297                 default:
 298                         warnx("Unknown .netrc keyword %s", tokval);
 299                         break;
 300                 }
 301                 goto done;
 302         }
 303 done:
 304         (void) fclose(cfile);
 305         return (0);
 306 bad:
 307         (void) fclose(cfile);
 308         return (-1);
 309 }
 310
 311 extern "C" int
 312 cygwin_rexec (char **ahost, unsigned short rport, char *name, char *pass,
 313               char *cmd, int *fd2p)
 314 {
 315         struct sockaddr_in sin, sin2, from;
 316         struct hostent *hp;
 317         u_short port = 0;
 318         int s, timo = 1, s3;
 319         char c;
 320         char ahostbuf[INTERNET_MAX_HOST_NAME_LENGTH + 1];
 321
 322         myfault efault;
 323         if (efault.faulted (EFAULT))
 324                 return -1;
 325
 326         hp = cygwin_gethostbyname(*ahost);
 327         if (hp == 0) {
 328                 cygwin_herror(*ahost);
 329                 return (-1);
 330         }
 331         *ahost = strcpy (ahostbuf, hp->h_name);
 332         ruserpass(hp->h_name, &name, &pass, NULL);
 333         if (!name)
 334                 name = getlogin ();
 335         if (!pass)
 336                 pass = almost_null;
 337 retry:
 338         s = cygwin_socket(AF_INET, SOCK_STREAM, 0);
 339         if (s < 0) {
 340                 perror("rexec: socket");
 341                 return (-1);
 342         }
 343         sin.sin_family = hp->h_addrtype;
 344         sin.sin_port = rport;
 345         bcopy(hp->h_addr, (caddr_t)&sin.sin_addr, hp->h_length);
 346         if (cygwin_connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
 347                 if (errno == ECONNREFUSED && timo <= 16) {
 348                         (void) close(s);
 349                         sleep(timo);
 350                         timo *= 2;
 351                         goto retry;
 352                 }
 353                 perror(hp->h_name);
 354                 return (-1);
 355         }
 356         if (fd2p == 0) {
 357                 (void) write(s, "", 1);
 358         } else {
 359                 char num[8];
 360                 int s2, sin2len;
 361
 362                 s2 = cygwin_socket(AF_INET, SOCK_STREAM, 0);
 363                 if (s2 < 0) {
 364                         (void) close(s);
 365                         return (-1);
 366                 }
 367                 cygwin_listen(s2, 1);
 368                 sin2len = sizeof (sin2);
 369                 if (cygwin_getsockname(s2, (struct sockaddr *)&sin2, &sin2len) < 0 ||
 370                   sin2len != sizeof (sin2)) {
 371                         perror("getsockname");
 372                         (void) close(s2);
 373                         goto bad;
 374                 }
 375                 port = ntohs((u_short)sin2.sin_port);
 376                 (void) sprintf(num, "%u", port);
 377                 (void) write(s, num, strlen(num)+1);
 378                 { int len = sizeof (from);
 379                   s3 = cygwin_accept(s2, (struct sockaddr *)&from, &len);
 380                   close(s2);
 381                   if (s3 < 0) {
 382                         perror("accept");
 383                         port = 0;
 384                         goto bad;
 385                   }
 386                 }
 387                 *fd2p = s3;
 388         }
 389         (void) write(s, name, strlen(name) + 1);
 390         /* should public key encypt the password here */
 391         (void) write(s, pass, strlen(pass) + 1);
 392         (void) write(s, cmd, strlen(cmd) + 1);
 393         if (read(s, &c, 1) != 1) {
 394                 perror(*ahost);
 395                 goto bad;
 396         }
 397         if (c != 0) {
 398                 while (read(s, &c, 1) == 1) {
 399                         (void) write(2, &c, 1);
 400                         if (c == '\n')
 401                                 break;
 402                 }
 403                 goto bad;
 404         }
 405         return (s);
 406 bad:
 407         if (port)
 408                 (void) close(*fd2p);
 409         (void) close(s);
 410         return (-1);
 411 }