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 #endif  /* KPOP */
 212
 213     for (ap = nets; ap < n1; ap++)
 214         if (ap->a_addrtype == hp->h_addrtype && inet (hp, ap->a_net))
 215             return NOTOK;
 216
 217     for (ap = hosts; ap < h1; ap++)
 218         if (ap->a_addrtype == hp->h_addrtype
 219                 && memcmp(ap->a_addr, hp->h_addr, hp->h_length) == 0)
 220             return NOTOK;
 221
 222     if ((sd = getport (rproto, hp->h_addrtype, response, len_response)) == NOTOK)
 223         return OOPS2;
 224
 225     memset (isock, 0, sizeof(*isock));
 226     isock->sin_family = hp->h_addrtype;
 227     inaddr_copy (hp, isock);
 228     isock->sin_port = sp->s_port;
 229
 230     if (connect (sd, (struct sockaddr *) isock, sizeof(*isock)) == NOTOK)
 231         switch (errno) {
 232             case ENETDOWN:
 233             case ENETUNREACH:
 234                 close (sd);
 235                 if (n1 < n2) {
 236                     n1->a_addrtype = hp->h_addrtype;
 237                     memcpy(&in, hp->h_addr, sizeof(in));
 238                     n1->a_net = inet_netof (in);
 239                     n1++;
 240                 }
 241                 return OOPS1;
 242
 243             case ETIMEDOUT:
 244             case ECONNREFUSED:
 245             default:
 246                 close (sd);
 247                 if (h1 < h2) {
 248                     h1->a_addrtype = hp->h_addrtype;
 249                     memcpy(h1->a_addr, hp->h_addr, hp->h_length);
 250                     h1++;
 251                 }
 252                 return NOTOK;
 253         }
 254
 255 #ifdef KPOP
 256     if (kservice) {     /* "pop" */
 257         char *instance;
 258
 259         if ((instance = strdup (hp->h_name)) == NULL) {
 260             close (sd);
 261             strncpy (response, "Out of memory.", len_response);
 262             return OOPS2;
 263         }
 264         ticket = (KTEXT) malloc (sizeof(KTEXT_ST));
 265         rem = krb_sendauth (0L, sd, ticket, kservice, instance,
 266                            (char *) krb_realmofhost (instance),
 267                            (unsigned long) 0, &msg_data, &cred, schedule,
 268                            (struct sockaddr_in *) NULL,
 269                            (struct sockaddr_in *) NULL,
 270                            "KPOPV0.1");
 271         free (instance);
 272         if (rem != KSUCCESS) {
 273             close (sd);
 274             strncpy (response, "Post office refused connection: ", len_response);
 275             strncat (response, krb_err_txt[rem], len_response - strlen(response));
 276             return OOPS2;
 277         }
 278     }
 279 #endif /* KPOP */
 280
 281     return sd;
 282 }
 283
 284
 285 static int
 286 getport (int rproto, int addrtype, char *response, int len_response)
 287 {
 288     int sd, port;
 289     struct sockaddr_in in_socket, *isock;
 290
 291     isock = &in_socket;
 292     if (rproto && addrtype != AF_INET) {
 293         snprintf (response, len_response, "reserved ports not supported for af=%d", addrtype);
 294         errno = ENOPROTOOPT;
 295         return NOTOK;
 296     }
 297
 298     if ((sd = socket (AF_INET, SOCK_STREAM, 0)) == NOTOK) {
 299         char *s;
 300
 301         if ((s = strerror (errno)))
 302             snprintf (response, len_response, "unable to create socket: %s", s);
 303         else
 304             snprintf (response, len_response, "unable to create socket: unknown error");
 305         return NOTOK;
 306     }
 307 #ifdef KPOP
 308     if (kservice)       /* "pop" */
 309         return(sd);
 310 #endif  /* KPOP */
 311     if (!rproto)
 312         return sd;
 313
 314     memset(isock, 0, sizeof(*isock));
 315     isock->sin_family = addrtype;
 316     for (port = IPPORT_RESERVED - 1;;) {
 317         isock->sin_port = htons ((unsigned short) port);
 318         if (bind (sd, (struct sockaddr *) isock, sizeof(*isock)) != NOTOK)
 319             return sd;
 320
 321         switch (errno) {
 322             char *s;
 323
 324             case EADDRINUSE:
 325             case EADDRNOTAVAIL:
 326                 if (--port <= IPPORT_RESERVED / 2) {
 327                     strncpy (response, "ports available", len_response);
 328                     return NOTOK;
 329                 }
 330                 break;
 331
 332             default:
 333                 if ((s = strerror (errno)))
 334                     snprintf (response, len_response, "unable to bind socket: %s", s);
 335                 else
 336                     snprintf (response, len_response, "unable to bind socket: unknown error");
 337                 return NOTOK;
 338         }
 339     }
 340 }
 341
 342
 343 static int
 344 inet (struct hostent *hp, int net)
 345 {
 346     struct in_addr in;
 347
 348     memcpy(&in, hp->h_addr, sizeof(in));
 349     return (inet_netof (in) == net);
 350 }
 351
 352
 353 /*
 354  * taken from ISODE's compat/internet.c
 355  */
 356
 357 static char *empty = NULL;
 358
 359 #ifdef h_addr
 360 static char *addrs[2] = { NULL };
 361 #endif
 362
 363 struct hostent *
 364 gethostbystring (char *s)
 365 {
 366     register struct hostent *h;
 367     static struct hostent hs;
 368 #ifdef DG
 369     static struct in_addr iaddr;
 370 #else
 371     static unsigned long iaddr;
 372 #endif
 373
 374     iaddr = inet_addr (s);
 375 #ifdef DG
 376     if (iaddr.s_addr == NOTOK && strcmp (s, "255.255.255.255"))
 377 #else
 378     if (((int) iaddr == NOTOK) && strcmp (s, "255.255.255.255"))
 379 #endif
 380         return gethostbyname (s);
 381
 382     h = &hs;
 383     h->h_name = s;
 384     h->h_aliases = &empty;
 385     h->h_addrtype = AF_INET;
 386     h->h_length = sizeof(iaddr);
 387 #ifdef h_addr
 388     h->h_addr_list = addrs;
 389     memset(addrs, 0, sizeof(addrs));
 390 #endif
 391     h->h_addr = (char *) &iaddr;
 392
 393     return h;
 394 }
 395
 396
 397 /*
 398  * static copies of three nmh subroutines
 399  */
 400
 401 static char *broken[MAXARGS + 1];
 402
 403 static char **
 404 client_brkstring (char *strg, char *brksep, char *brkterm)
 405 {
 406     register int bi;
 407     register char c, *sp;
 408
 409     sp = strg;
 410
 411     for (bi = 0; bi < MAXARGS; bi++) {
 412         while (client_brkany (c = *sp, brksep))
 413             *sp++ = 0;
 414         if (!c || client_brkany (c, brkterm)) {
 415             *sp = 0;
 416             broken[bi] = 0;
 417             return broken;
 418         }
 419
 420         broken[bi] = sp;
 421         while ((c = *++sp) && !client_brkany (c, brksep) && !client_brkany (c, brkterm))
 422             continue;
 423     }
 424     broken[MAXARGS] = 0;
 425
 426     return broken;
 427 }
 428
 429
 430 /*
 431  * returns 1 if chr in strg, 0 otherwise
 432  */
 433 static int
 434 client_brkany (char chr, char *strg)
 435 {
 436     register char *sp;
 437
 438     if (strg)
 439         for (sp = strg; *sp; sp++)
 440             if (chr == *sp)
 441                 return 1;
 442     return 0;
 443 }
 444
 445
 446 /*
 447  * copy a string array and return pointer to end
 448  */
 449 static char **
 450 client_copyip (char **p, char **q, int len_q)
 451 {
 452     while (*p && --len_q > 0)
 453         *q++ = *p++;
 454
 455     *q = NULL;
 456
 457     return q;
 458 }
 459
 460
 461 static char *
 462 client_getcpy (char *str)
 463 {
 464     char *cp;
 465     size_t len;
 466
 467     len = strlen(str) + 1;
 468     if (!(cp = malloc(len)))
 469         return NULL;
 470
 471     memcpy (cp, str, len);
 472     return cp;
 473 }
 474