diplodocus.org Git - nmh/blob - zotnet/mts/client.c

   1
   2 /*
   3  * client.c -- connect to a server
   4  *
   5  * $Id$
   6  */
   7
   8 #include <h/mh.h>
   9 #include <mts.h>
  10 #include <errno.h>
  11 #include <sys/socket.h>
  12 #include <netinet/in.h>
  13 #include <netdb.h>
  14
  15 #ifdef HAVE_ARPA_INET_H
  16 # include <arpa/inet.h>
  17 #endif
  18
  19 #ifdef HESIOD
  20 # include <hesiod.h>
  21 #endif
  22
  23 #ifdef KPOP
  24 # include <krb.h>
  25 # include <ctype.h>
  26 #endif  /* KPOP */
  27
  28 #define TRUE         1
  29 #define FALSE        0
  30
  31 #define OOPS1      (-2)
  32 #define OOPS2      (-3)
  33
  34 #define MAXARGS   1000
  35 #define MAXNETS      5
  36 #define MAXHOSTS    25
  37
  38 struct addrent {
  39     int a_addrtype;             /* assumes AF_INET for inet_netof () */
  40     union {
  41         int un_net;
  42         char un_addr[14];
  43     } un;
  44 };
  45
  46 #define a_net  un.un_net
  47 #define a_addr un.un_addr
  48
  49 static struct addrent *n1, *n2;
  50 static struct addrent nets[MAXNETS];
  51 static struct addrent *h1, *h2;
  52 static struct addrent hosts[MAXHOSTS];
  53
  54 #ifdef KPOP
  55 static CREDENTIALS cred;
  56 static MSG_DAT msg_data;
  57 static KTEXT ticket = (KTEXT) NULL;
  58 static Key_schedule schedule;
  59 static char *kservice;                  /* "pop" if using kpop */
  60 char krb_realm[REALM_SZ];
  61 char *PrincipalHostname();
  62 #endif /* KPOP */
  63
  64 #if !defined(h_addr)
  65 # define h_addr h_addr_list[0]
  66 #endif
  67
  68 #define inaddr_copy(hp,sin) \
  69     memcpy(&((sin)->sin_addr), (hp)->h_addr, (hp)->h_length)
  70
  71 /*
  72  * static prototypes
  73  */
  74 static int rcaux (struct servent *, struct hostent *, int, char *, int);
  75 static int getport (int, int, char *, int);
  76 static int inet (struct hostent *, int);
  77 struct hostent *gethostbystring (char *s);
  78
  79 /* client's own static version of several nmh subroutines */
  80 static char **client_brkstring (char *, char *, char *);
  81 static int client_brkany (char, char *);
  82 static char **client_copyip (char **, char **, int);
  83 static char *client_getcpy (char *);
  84
  85
  86 int
  87 client (char *args, char *protocol, char *service, int rproto,
  88                 char *response, int len_response)
  89 {
  90     int sd;
  91     register char **ap;
  92     char *arguments[MAXARGS];
  93     register struct hostent *hp;
  94     register struct servent *sp;
  95 /* we assume netent and getnetbyaddr come with gethostbyname */
  96 #ifdef  HAVE_GETHOSTBYNAME
  97     register struct netent *np;
  98 #endif
  99
 100 #ifdef KPOP
 101     char *cp;
 102
 103     kservice = service;
 104     if (cp = strchr (service, '/')) {   /* "pop/kpop" */
 105         *cp++ = '\0';           /* kservice = "pop" */
 106         service = cp;           /* service  = "kpop" */
 107     } else {
 108         kservice = NULL;        /* not using KERBEROS */
 109     }
 110 #endif  /* KPOP */
 111
 112
 113     if ((sp = getservbyname (service, protocol)) == NULL) {
 114 #ifdef HESIOD
 115         if ((sp = hes_getservbyname (service, protocol)) == NULL) {
 116             snprintf (response, len_response, "%s/%s: unknown service", protocol, service);
 117             return NOTOK;
 118         }
 119 #else
 120         snprintf (response, len_response, "%s/%s: unknown service", protocol, service);
 121         return NOTOK;
 122 #endif
 123     }
 124
 125     ap = arguments;
 126     if (args != NULL && *args != 0) {
 127         ap = client_copyip (client_brkstring (client_getcpy (args), " ", "\n"),
 128                 ap, MAXARGS);
 129     } else {
 130         if (servers != NULL && *servers != 0)
 131             ap = client_copyip (client_brkstring (client_getcpy (servers), " ", "\n"),
 132                 ap, MAXARGS);
 133     }
 134     if (ap == arguments) {
 135         *ap++ = client_getcpy ("localhost");
 136         *ap = NULL;
 137     }
 138
 139     n1 = nets;
 140     n2 = nets + sizeof(nets) / sizeof(nets[0]);
 141
 142     h1 = hosts;
 143     h2 = hosts + sizeof(hosts) / sizeof(hosts[0]);
 144
 145     for (ap = arguments; *ap; ap++) {
 146         if (**ap == '\01') {
 147 /*
 148  * the assumption here is that if the system doesn't have a
 149  * gethostbyname() function, it must not use DNS. So we need to look
 150  * into the /etc/hosts using gethostent(). There probablly aren't any
 151  * systems still like this, but you never know. On every system I have
 152  * access to, this section is ignored.
 153  */
 154 #ifndef HAVE_GETHOSTBYNAME
 155             if ((np = getnetbyname (*ap + 1))) {
 156 #ifdef HAVE_SETHOSTENT
 157                 sethostent (1);
 158 #endif /* HAVE_SETHOSTENT */
 159                 while ((hp = gethostent()))
 160                     if (np->n_addrtype == hp->h_addrtype
 161                             && inet (hp, np->n_net)) {
 162                         switch (sd = rcaux (sp, hp, rproto, response, len_response)) {
 163                             case NOTOK:
 164                                 continue;
 165                             case OOPS1:
 166                                 break;
 167                             case OOPS2:
 168                                 return NOTOK;
 169
 170                             default:
 171                                 return sd;
 172                         }
 173                         break;
 174                     }
 175             }
 176 #endif /* don't HAVE_GETHOSTBYNAME */
 177             continue;
 178         }
 179
 180         if ((hp = gethostbystring (*ap))) {
 181             switch (sd = rcaux (sp, hp, rproto, response, len_response)) {
 182                 case NOTOK:
 183                 case OOPS1:
 184                     break;
 185                 case OOPS2:
 186                     return NOTOK;
 187
 188                 default:
 189                     return sd;
 190             }
 191             continue;
 192         }
 193     }
 194
 195     strncpy (response, "no servers available", len_response);
 196     return NOTOK;
 197 }
 198
 199
 200 static int
 201 rcaux (struct servent *sp, struct hostent *hp, int rproto,
 202                 char *response, int len_response)
 203 {
 204     int sd;
 205     struct in_addr in;
 206     register struct addrent *ap;
 207     struct sockaddr_in in_socket;
 208     register struct sockaddr_in *isock = &in_socket;
 209
 210 #ifdef KPOP
 211     int rem;
 212 #endif  /* KPOP */
 213
 214     for (ap = nets; ap < n1; ap++)
 215         if (ap->a_addrtype == hp->h_addrtype && inet (hp, ap->a_net))
 216             return NOTOK;
 217
 218     for (ap = hosts; ap < h1; ap++)
 219         if (ap->a_addrtype == hp->h_addrtype
 220                 && memcmp(ap->a_addr, hp->h_addr, hp->h_length) == 0)
 221             return NOTOK;
 222
 223     if ((sd = getport (rproto, hp->h_addrtype, response, len_response)) == NOTOK)
 224         return OOPS2;
 225
 226     memset (isock, 0, sizeof(*isock));
 227     isock->sin_family = hp->h_addrtype;
 228     inaddr_copy (hp, isock);
 229     isock->sin_port = sp->s_port;
 230
 231     if (connect (sd, (struct sockaddr *) isock, sizeof(*isock)) == NOTOK)
 232         switch (errno) {
 233             case ENETDOWN:
 234             case ENETUNREACH:
 235                 close (sd);
 236                 if (n1 < n2) {
 237                     n1->a_addrtype = hp->h_addrtype;
 238                     memcpy(&in, hp->h_addr, sizeof(in));
 239                     n1->a_net = inet_netof (in);
 240                     n1++;
 241                 }
 242                 return OOPS1;
 243
 244             case ETIMEDOUT:
 245             case ECONNREFUSED:
 246             default:
 247                 close (sd);
 248                 if (h1 < h2) {
 249                     h1->a_addrtype = hp->h_addrtype;
 250                     memcpy(h1->a_addr, hp->h_addr, hp->h_length);
 251                     h1++;
 252                 }
 253                 return NOTOK;
 254         }
 255
 256 #ifdef KPOP
 257     if (kservice) {     /* "pop" */
 258         char *instance;
 259
 260         if ((instance = strdup (hp->h_name)) == NULL) {
 261             close (sd);
 262             strncpy (response, "Out of memory.", len_response);
 263             return OOPS2;
 264         }
 265         ticket = (KTEXT) malloc (sizeof(KTEXT_ST));
 266         rem = krb_sendauth (0L, sd, ticket, kservice, instance,
 267                            (char *) krb_realmofhost (instance),
 268                            (unsigned long) 0, &msg_data, &cred, schedule,
 269                            (struct sockaddr_in *) NULL,
 270                            (struct sockaddr_in *) NULL,
 271                            "KPOPV0.1");
 272         free (instance);
 273         if (rem != KSUCCESS) {
 274             close (sd);
 275             strncpy (response, "Post office refused connection: ", len_response);
 276             strncat (response, krb_err_txt[rem], len_response - strlen(response));
 277             return OOPS2;
 278         }
 279     }
 280 #endif /* KPOP */
 281
 282     return sd;
 283 }
 284
 285
 286 static int
 287 getport (int rproto, int addrtype, char *response, int len_response)
 288 {
 289     int sd, port;
 290     struct sockaddr_in in_socket, *isock;
 291
 292     isock = &in_socket;
 293     if (rproto && addrtype != AF_INET) {
 294         snprintf (response, len_response, "reserved ports not supported for af=%d", addrtype);
 295         errno = ENOPROTOOPT;
 296         return NOTOK;
 297     }
 298
 299     if ((sd = socket (AF_INET, SOCK_STREAM, 0)) == NOTOK) {
 300         char *s;
 301
 302         if ((s = strerror (errno)))
 303             snprintf (response, len_response, "unable to create socket: %s", s);
 304         else
 305             snprintf (response, len_response, "unable to create socket: unknown error");
 306         return NOTOK;
 307     }
 308 #ifdef KPOP
 309     if (kservice)       /* "pop" */
 310         return(sd);
 311 #endif  /* KPOP */
 312     if (!rproto)
 313         return sd;
 314
 315     memset(isock, 0, sizeof(*isock));
 316     isock->sin_family = addrtype;
 317     for (port = IPPORT_RESERVED - 1;;) {
 318         isock->sin_port = htons ((unsigned short) port);
 319         if (bind (sd, (struct sockaddr *) isock, sizeof(*isock)) != NOTOK)
 320             return sd;
 321
 322         switch (errno) {
 323             char *s;
 324
 325             case EADDRINUSE:
 326             case EADDRNOTAVAIL:
 327                 if (--port <= IPPORT_RESERVED / 2) {
 328                     strncpy (response, "ports available", len_response);
 329                     return NOTOK;
 330                 }
 331                 break;
 332
 333             default:
 334                 if ((s = strerror (errno)))
 335                     snprintf (response, len_response, "unable to bind socket: %s", s);
 336                 else
 337                     snprintf (response, len_response, "unable to bind socket: unknown error");
 338                 return NOTOK;
 339         }
 340     }
 341 }
 342
 343
 344 static int
 345 inet (struct hostent *hp, int net)
 346 {
 347     struct in_addr in;
 348
 349     memcpy(&in, hp->h_addr, sizeof(in));
 350     return (inet_netof (in) == net);
 351 }
 352
 353
 354 /*
 355  * taken from ISODE's compat/internet.c
 356  */
 357
 358 static char *empty = NULL;
 359
 360 #ifdef h_addr
 361 static char *addrs[2] = { NULL };
 362 #endif
 363
 364 struct hostent *
 365 gethostbystring (char *s)
 366 {
 367     register struct hostent *h;
 368     static struct hostent hs;
 369 #ifdef DG
 370     static struct in_addr iaddr;
 371 #else
 372     static unsigned long iaddr;
 373 #endif
 374
 375     iaddr = inet_addr (s);
 376 #ifdef DG
 377     if (iaddr.s_addr == NOTOK && strcmp (s, "255.255.255.255"))
 378 #else
 379     if (((int) iaddr == NOTOK) && strcmp (s, "255.255.255.255"))
 380 #endif
 381         return gethostbyname (s);
 382
 383     h = &hs;
 384     h->h_name = s;
 385     h->h_aliases = &empty;
 386     h->h_addrtype = AF_INET;
 387     h->h_length = sizeof(iaddr);
 388 #ifdef h_addr
 389     h->h_addr_list = addrs;
 390     memset(addrs, 0, sizeof(addrs));
 391 #endif
 392     h->h_addr = (char *) &iaddr;
 393
 394     return h;
 395 }
 396
 397
 398 /*
 399  * static copies of three nmh subroutines
 400  */
 401
 402 static char *broken[MAXARGS + 1];
 403
 404 static char **
 405 client_brkstring (char *strg, char *brksep, char *brkterm)
 406 {
 407     register int bi;
 408     register char c, *sp;
 409
 410     sp = strg;
 411
 412     for (bi = 0; bi < MAXARGS; bi++) {
 413         while (client_brkany (c = *sp, brksep))
 414             *sp++ = 0;
 415         if (!c || client_brkany (c, brkterm)) {
 416             *sp = 0;
 417             broken[bi] = 0;
 418             return broken;
 419         }
 420
 421         broken[bi] = sp;
 422         while ((c = *++sp) && !client_brkany (c, brksep) && !client_brkany (c, brkterm))
 423             continue;
 424     }
 425     broken[MAXARGS] = 0;
 426
 427     return broken;
 428 }
 429
 430
 431 /*
 432  * returns 1 if chr in strg, 0 otherwise
 433  */
 434 static int
 435 client_brkany (char chr, char *strg)
 436 {
 437     register char *sp;
 438
 439     if (strg)
 440         for (sp = strg; *sp; sp++)
 441             if (chr == *sp)
 442                 return 1;
 443     return 0;
 444 }
 445
 446
 447 /*
 448  * copy a string array and return pointer to end
 449  */
 450 static char **
 451 client_copyip (char **p, char **q, int len_q)
 452 {
 453     while (*p && --len_q > 0)
 454         *q++ = *p++;
 455
 456     *q = NULL;
 457
 458     return q;
 459 }
 460
 461
 462 static char *
 463 client_getcpy (char *str)
 464 {
 465     char *cp;
 466     size_t len;
 467
 468     len = strlen(str) + 1;
 469     if (!(cp = malloc(len)))
 470         return NULL;
 471
 472     memcpy (cp, str, len);
 473     return cp;
 474 }
 475