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 #ifndef HAVE_GETHOSTBYNAME
  96     register struct netent *np;
  97 #endif
  98
  99 #ifdef KPOP
 100     char *cp;
 101
 102     kservice = service;
 103     if (cp = strchr (service, '/')) {   /* "pop/kpop" */
 104         *cp++ = '\0';           /* kservice = "pop" */
 105         service = cp;           /* service  = "kpop" */
 106     } else {
 107         kservice = NULL;        /* not using KERBEROS */
 108     }
 109 #endif  /* KPOP */
 110
 111
 112     if ((sp = getservbyname (service, protocol)) == NULL) {
 113 #ifdef HESIOD
 114         if ((sp = hes_getservbyname (service, protocol)) == NULL) {
 115             snprintf (response, len_response, "%s/%s: unknown service", protocol, service);
 116             return NOTOK;
 117         }
 118 #else
 119         snprintf (response, len_response, "%s/%s: unknown service", protocol, service);
 120         return NOTOK;
 121 #endif
 122     }
 123
 124     ap = arguments;
 125     if (args != NULL && *args != 0) {
 126         ap = client_copyip (client_brkstring (client_getcpy (args), " ", "\n"),
 127                 ap, MAXARGS);
 128     } else {
 129         if (servers != NULL && *servers != 0)
 130             ap = client_copyip (client_brkstring (client_getcpy (servers), " ", "\n"),
 131                 ap, MAXARGS);
 132     }
 133     if (ap == arguments) {
 134         *ap++ = client_getcpy ("localhost");
 135         *ap = NULL;
 136     }
 137
 138     n1 = nets;
 139     n2 = nets + sizeof(nets) / sizeof(nets[0]);
 140
 141     h1 = hosts;
 142     h2 = hosts + sizeof(hosts) / sizeof(hosts[0]);
 143
 144     for (ap = arguments; *ap; ap++) {
 145         if (**ap == '\01') {
 146 /*
 147  * the assumption here is that if the system doesn't have a
 148  * gethostbyname() function, it must not use DNS. So we need to look
 149  * into the /etc/hosts using gethostent(). There probablly aren't any
 150  * systems still like this, but you never know. On every system I have
 151  * access to, this section is ignored.
 152  */
 153 #ifndef HAVE_GETHOSTBYNAME
 154             if ((np = getnetbyname (*ap + 1))) {
 155 #ifdef HAVE_SETHOSTENT
 156                 sethostent (1);
 157 #endif /* HAVE_SETHOSTENT */
 158                 while ((hp = gethostent()))
 159                     if (np->n_addrtype == hp->h_addrtype
 160                             && inet (hp, np->n_net)) {
 161                         switch (sd = rcaux (sp, hp, rproto, response, len_response)) {
 162                             case NOTOK:
 163                                 continue;
 164                             case OOPS1:
 165                                 break;
 166                             case OOPS2:
 167                                 return NOTOK;
 168
 169                             default:
 170                                 return sd;
 171                         }
 172                         break;
 173                     }
 174             }
 175 #endif /* don't HAVE_GETHOSTBYNAME */
 176             continue;
 177         }
 178
 179         if ((hp = gethostbystring (*ap))) {
 180             switch (sd = rcaux (sp, hp, rproto, response, len_response)) {
 181                 case NOTOK:
 182                 case OOPS1:
 183                     break;
 184                 case OOPS2:
 185                     return NOTOK;
 186
 187                 default:
 188                     return sd;
 189             }
 190             continue;
 191         }
 192     }
 193
 194     strncpy (response, "no servers available", len_response);
 195     return NOTOK;
 196 }
 197
 198
 199 static int
 200 rcaux (struct servent *sp, struct hostent *hp, int rproto,
 201                 char *response, int len_response)
 202 {
 203     int sd;
 204     struct in_addr in;
 205     register struct addrent *ap;
 206     struct sockaddr_in in_socket;
 207     register struct sockaddr_in *isock = &in_socket;
 208
 209 #ifdef KPOP
 210     int rem;
 211     struct hostent *hp2;
 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 (( hp2 = gethostbyaddr( hp->h_addr, hp->h_length, hp->h_addrtype ))
 261                 == NULL ) {
 262             return NOTOK;
 263         }
 264         if ((instance = strdup (hp2->h_name)) == NULL) {
 265             close (sd);
 266             strncpy (response, "Out of memory.", len_response);
 267             return OOPS2;
 268         }
 269         ticket = (KTEXT) malloc (sizeof(KTEXT_ST));
 270         rem = krb_sendauth (0L, sd, ticket, kservice, instance,
 271                            (char *) krb_realmofhost (instance),
 272                            (unsigned long) 0, &msg_data, &cred, schedule,
 273                            (struct sockaddr_in *) NULL,
 274                            (struct sockaddr_in *) NULL,
 275                            "KPOPV0.1");
 276         free (instance);
 277         if (rem != KSUCCESS) {
 278             close (sd);
 279             strncpy (response, "Post office refused connection: ", len_response);
 280             strncat (response, krb_err_txt[rem], len_response - strlen(response));
 281             return OOPS2;
 282         }
 283     }
 284 #endif /* KPOP */
 285
 286     return sd;
 287 }
 288
 289
 290 static int
 291 getport (int rproto, int addrtype, char *response, int len_response)
 292 {
 293     int sd, port;
 294     struct sockaddr_in in_socket, *isock;
 295
 296     isock = &in_socket;
 297     if (rproto && addrtype != AF_INET) {
 298         snprintf (response, len_response, "reserved ports not supported for af=%d", addrtype);
 299         errno = ENOPROTOOPT;
 300         return NOTOK;
 301     }
 302
 303     if ((sd = socket (AF_INET, SOCK_STREAM, 0)) == NOTOK) {
 304         char *s;
 305
 306         if ((s = strerror (errno)))
 307             snprintf (response, len_response, "unable to create socket: %s", s);
 308         else
 309             snprintf (response, len_response, "unable to create socket: unknown error");
 310         return NOTOK;
 311     }
 312 #ifdef KPOP
 313     if (kservice)       /* "pop" */
 314         return(sd);
 315 #endif  /* KPOP */
 316     if (!rproto)
 317         return sd;
 318
 319     memset(isock, 0, sizeof(*isock));
 320     isock->sin_family = addrtype;
 321     for (port = IPPORT_RESERVED - 1;;) {
 322         isock->sin_port = htons ((unsigned short) port);
 323         if (bind (sd, (struct sockaddr *) isock, sizeof(*isock)) != NOTOK)
 324             return sd;
 325
 326         switch (errno) {
 327             char *s;
 328
 329             case EADDRINUSE:
 330             case EADDRNOTAVAIL:
 331                 if (--port <= IPPORT_RESERVED / 2) {
 332                     strncpy (response, "ports available", len_response);
 333                     return NOTOK;
 334                 }
 335                 break;
 336
 337             default:
 338                 if ((s = strerror (errno)))
 339                     snprintf (response, len_response, "unable to bind socket: %s", s);
 340                 else
 341                     snprintf (response, len_response, "unable to bind socket: unknown error");
 342                 return NOTOK;
 343         }
 344     }
 345 }
 346
 347
 348 static int
 349 inet (struct hostent *hp, int net)
 350 {
 351     struct in_addr in;
 352
 353     memcpy(&in, hp->h_addr, sizeof(in));
 354     return (inet_netof (in) == net);
 355 }
 356
 357
 358 /*
 359  * taken from ISODE's compat/internet.c
 360  */
 361
 362 static char *empty = NULL;
 363
 364 #ifdef h_addr
 365 static char *addrs[2] = { NULL };
 366 #endif
 367
 368 struct hostent *
 369 gethostbystring (char *s)
 370 {
 371     register struct hostent *h;
 372     static struct hostent hs;
 373 #ifdef DG
 374     static struct in_addr iaddr;
 375 #else
 376     static unsigned long iaddr;
 377 #endif
 378
 379     iaddr = inet_addr (s);
 380 #ifdef DG
 381     if (iaddr.s_addr == NOTOK && strcmp (s, "255.255.255.255"))
 382 #else
 383     if (((int) iaddr == NOTOK) && strcmp (s, "255.255.255.255"))
 384 #endif
 385         return gethostbyname (s);
 386
 387     h = &hs;
 388     h->h_name = s;
 389     h->h_aliases = &empty;
 390     h->h_addrtype = AF_INET;
 391     h->h_length = sizeof(iaddr);
 392 #ifdef h_addr
 393     h->h_addr_list = addrs;
 394     memset(addrs, 0, sizeof(addrs));
 395 #endif
 396     h->h_addr = (char *) &iaddr;
 397
 398     return h;
 399 }
 400
 401
 402 /*
 403  * static copies of three nmh subroutines
 404  */
 405
 406 static char *broken[MAXARGS + 1];
 407
 408 static char **
 409 client_brkstring (char *strg, char *brksep, char *brkterm)
 410 {
 411     register int bi;
 412     register char c, *sp;
 413
 414     sp = strg;
 415
 416     for (bi = 0; bi < MAXARGS; bi++) {
 417         while (client_brkany (c = *sp, brksep))
 418             *sp++ = 0;
 419         if (!c || client_brkany (c, brkterm)) {
 420             *sp = 0;
 421             broken[bi] = 0;
 422             return broken;
 423         }
 424
 425         broken[bi] = sp;
 426         while ((c = *++sp) && !client_brkany (c, brksep) && !client_brkany (c, brkterm))
 427             continue;
 428     }
 429     broken[MAXARGS] = 0;
 430
 431     return broken;
 432 }
 433
 434
 435 /*
 436  * returns 1 if chr in strg, 0 otherwise
 437  */
 438 static int
 439 client_brkany (char chr, char *strg)
 440 {
 441     register char *sp;
 442
 443     if (strg)
 444         for (sp = strg; *sp; sp++)
 445             if (chr == *sp)
 446                 return 1;
 447     return 0;
 448 }
 449
 450
 451 /*
 452  * copy a string array and return pointer to end
 453  */
 454 static char **
 455 client_copyip (char **p, char **q, int len_q)
 456 {
 457     while (*p && --len_q > 0)
 458         *q++ = *p++;
 459
 460     *q = NULL;
 461
 462     return q;
 463 }
 464
 465
 466 static char *
 467 client_getcpy (char *str)
 468 {
 469     char *cp;
 470     size_t len;
 471
 472     len = strlen(str) + 1;
 473     if (!(cp = malloc(len)))
 474         return NULL;
 475
 476     memcpy (cp, str, len);
 477     return cp;
 478 }
 479