cups/auth.c

   1 /*
   2  * "$Id: auth.c 7720 2008-07-11 22:46:21Z mike $"
   3  *
   4  *   Authentication functions for CUPS.
   5  *
   6  *   Copyright 2007-2011 by Apple Inc.
   7  *   Copyright 1997-2007 by Easy Software Products.
   8  *
   9  *   This file contains Kerberos support code, copyright 2006 by
  10  *   Jelmer Vernooij.
  11  *
  12  *   These coded instructions, statements, and computer programs are the
  13  *   property of Apple Inc. and are protected by Federal copyright
  14  *   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
  15  *   which should have been included with this file.  If this file is
  16  *   file is missing or damaged, see the license at "http://www.cups.org/".
  17  *
  18  *   This file is subject to the Apple OS-Developed Software exception.
  19  *
  20  * Contents:
  21  *
  22  *   cupsDoAuthentication()        - Authenticate a request.
  23  *   _cupsSetNegotiateAuthString() - Set the Kerberos authentication string.
  24  *   cups_gss_acquire()            - Kerberos credentials callback.
  25  *   cups_gss_getname()            - Get CUPS service credentials for
  26  *                                   authentication.
  27  *   cups_gss_printf()             - Show debug error messages from GSSAPI.
  28  *   cups_local_auth()             - Get the local authorization certificate if
  29  *                                   available/applicable.
  30  */
  31
  32 /*
  33  * Include necessary headers...
  34  */
  35
  36 #include "cups-private.h"
  37 #include <fcntl.h>
  38 #include <sys/stat.h>
  39 #if defined(WIN32) || defined(__EMX__)
  40 #  include <io.h>
  41 #else
  42 #  include <unistd.h>
  43 #endif /* WIN32 || __EMX__ */
  44
  45 #if HAVE_AUTHORIZATION_H
  46 #  include <Security/Authorization.h>
  47 #  ifdef HAVE_SECBASEPRIV_H
  48 #    include <Security/SecBasePriv.h>
  49 #  else
  50 extern const char *cssmErrorString(int error);
  51 #  endif /* HAVE_SECBASEPRIV_H */
  52 #endif /* HAVE_AUTHORIZATION_H */
  53
  54 #if defined(SO_PEERCRED) && defined(AF_LOCAL)
  55 #  include <pwd.h>
  56 #endif /* SO_PEERCRED && AF_LOCAL */
  57
  58
  59 /*
  60  * Local functions...
  61  */
  62
  63 #ifdef HAVE_GSSAPI
  64 #  ifdef HAVE_GSS_ACQUIRE_CRED_EX_F
  65 #    ifdef HAVE_GSS_GSSAPI_SPI_H
  66 #      include <GSS/gssapi_spi.h>
  67 #    else
  68 #      define GSS_AUTH_IDENTITY_TYPE_1 1
  69 #      define gss_acquire_cred_ex_f __ApplePrivate_gss_acquire_cred_ex_f
  70 typedef struct gss_auth_identity
  71 {
  72   uint32_t type;
  73   uint32_t flags;
  74   char *username;
  75   char *realm;
  76   char *password;
  77   gss_buffer_t *credentialsRef;
  78 } gss_auth_identity_desc;
  79 extern OM_uint32 gss_acquire_cred_ex_f(gss_status_id_t, const gss_name_t,
  80                                        OM_uint32, OM_uint32, const gss_OID,
  81                                        gss_cred_usage_t, gss_auth_identity_t,
  82                                        void *, void (*)(void *, OM_uint32,
  83                                                         gss_status_id_t,
  84                                                         gss_cred_id_t,
  85                                                         gss_OID_set,
  86                                                         OM_uint32));
  87 #    endif /* HAVE_GSS_GSSAPI_SPI_H */
  88 #    include <dispatch/dispatch.h>
  89 typedef struct _cups_gss_acquire_s      /* Acquire callback data */
  90 {
  91   dispatch_semaphore_t  sem;            /* Synchronization semaphore */
  92   OM_uint32             major;          /* Returned status code */
  93   gss_cred_id_t         creds;          /* Returned credentials */
  94 } _cups_gss_acquire_t;
  95
  96 static void     cups_gss_acquire(void *ctx, OM_uint32 major,
  97                                  gss_status_id_t status,
  98                                  gss_cred_id_t creds, gss_OID_set oids,
  99                                  OM_uint32 time_rec);
 100 #  endif /* HAVE_GSS_ACQUIRE_CRED_EX_F */
 101 static gss_name_t cups_gss_getname(http_t *http, const char *service_name);
 102 #  ifdef DEBUG
 103 static void     cups_gss_printf(OM_uint32 major_status, OM_uint32 minor_status,
 104                                 const char *message);
 105 #  else
 106 #    define     cups_gss_printf(major, minor, message)
 107 #  endif /* DEBUG */
 108 #endif /* HAVE_GSSAPI */
 109 static int      cups_local_auth(http_t *http);
 110
 111
 112 /*
 113  * 'cupsDoAuthentication()' - Authenticate a request.
 114  *
 115  * This function should be called in response to a @code HTTP_UNAUTHORIZED@
 116  * status, prior to resubmitting your request.
 117  *
 118  * @since CUPS 1.1.20/Mac OS X 10.4@
 119  */
 120
 121 int                                     /* O - 0 on success, -1 on error */
 122 cupsDoAuthentication(
 123     http_t     *http,                   /* I - Connection to server or @code CUPS_HTTP_DEFAULT@ */
 124     const char *method,                 /* I - Request method ("GET", "POST", "PUT") */
 125     const char *resource)               /* I - Resource path */
 126 {
 127   const char    *password;              /* Password string */
 128   char          prompt[1024],           /* Prompt for user */
 129                 realm[HTTP_MAX_VALUE],  /* realm="xyz" string */
 130                 nonce[HTTP_MAX_VALUE];  /* nonce="xyz" string */
 131   int           localauth;              /* Local authentication result */
 132   _cups_globals_t *cg;                  /* Global data */
 133
 134
 135   DEBUG_printf(("cupsDoAuthentication(http=%p, method=\"%s\", resource=\"%s\")",
 136                 http, method, resource));
 137
 138   if (!http)
 139     http = _cupsConnect();
 140
 141   if (!http || !method || !resource)
 142     return (-1);
 143
 144   DEBUG_printf(("2cupsDoAuthentication: digest_tries=%d, userpass=\"%s\"",
 145                 http->digest_tries, http->userpass));
 146   DEBUG_printf(("2cupsDoAuthentication: WWW-Authenticate=\"%s\"",
 147                 httpGetField(http, HTTP_FIELD_WWW_AUTHENTICATE)));
 148
 149  /*
 150   * Clear the current authentication string...
 151   */
 152
 153   httpSetAuthString(http, NULL, NULL);
 154
 155  /*
 156   * See if we can do local authentication...
 157   */
 158
 159   if (http->digest_tries < 3)
 160   {
 161     if ((localauth = cups_local_auth(http)) == 0)
 162     {
 163       DEBUG_printf(("2cupsDoAuthentication: authstring=\"%s\"",
 164                     http->authstring));
 165
 166       if (http->status == HTTP_UNAUTHORIZED)
 167         http->digest_tries ++;
 168
 169       return (0);
 170     }
 171     else if (localauth == -1)
 172     {
 173       http->status = HTTP_AUTHORIZATION_CANCELED;
 174       return (-1);                      /* Error or canceled */
 175     }
 176   }
 177
 178  /*
 179   * Nope, see if we should retry the current username:password...
 180   */
 181
 182   if ((http->digest_tries > 1 || !http->userpass[0]) &&
 183       (!strncmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE], "Basic", 5) ||
 184        !strncmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE], "Digest", 6)))
 185   {
 186    /*
 187     * Nope - get a new password from the user...
 188     */
 189
 190     cg = _cupsGlobals();
 191
 192     if (!cg->lang_default)
 193       cg->lang_default = cupsLangDefault();
 194
 195     snprintf(prompt, sizeof(prompt),
 196              _cupsLangString(cg->lang_default, _("Password for %s on %s? ")),
 197              cupsUser(),
 198              http->hostname[0] == '/' ? "localhost" : http->hostname);
 199
 200     http->digest_tries  = _cups_strncasecmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE],
 201                                       "Digest", 5) != 0;
 202     http->userpass[0]   = '\0';
 203
 204     if ((password = cupsGetPassword2(prompt, http, method, resource)) == NULL)
 205     {
 206       http->status = HTTP_AUTHORIZATION_CANCELED;
 207       return (-1);
 208     }
 209
 210     snprintf(http->userpass, sizeof(http->userpass), "%s:%s", cupsUser(),
 211              password);
 212   }
 213   else if (http->status == HTTP_UNAUTHORIZED)
 214     http->digest_tries ++;
 215
 216   if (http->status == HTTP_UNAUTHORIZED && http->digest_tries >= 3)
 217   {
 218     DEBUG_printf(("1cupsDoAuthentication: Too many authentication tries (%d)",
 219                   http->digest_tries));
 220
 221     http->status = HTTP_AUTHORIZATION_CANCELED;
 222     return (-1);
 223   }
 224
 225  /*
 226   * Got a password; encode it for the server...
 227   */
 228
 229 #ifdef HAVE_GSSAPI
 230   if (!strncmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE], "Negotiate", 9))
 231   {
 232    /*
 233     * Kerberos authentication...
 234     */
 235
 236     if (_cupsSetNegotiateAuthString(http, method, resource))
 237     {
 238       http->status = HTTP_AUTHORIZATION_CANCELED;
 239       return (-1);
 240     }
 241   }
 242   else
 243 #endif /* HAVE_GSSAPI */
 244   if (!strncmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE], "Basic", 5))
 245   {
 246    /*
 247     * Basic authentication...
 248     */
 249
 250     char        encode[256];            /* Base64 buffer */
 251
 252
 253     httpEncode64_2(encode, sizeof(encode), http->userpass,
 254                    (int)strlen(http->userpass));
 255     httpSetAuthString(http, "Basic", encode);
 256   }
 257   else if (!strncmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE], "Digest", 6))
 258   {
 259    /*
 260     * Digest authentication...
 261     */
 262
 263     char        encode[33],             /* MD5 buffer */
 264                 digest[1024];           /* Digest auth data */
 265
 266
 267     httpGetSubField(http, HTTP_FIELD_WWW_AUTHENTICATE, "realm", realm);
 268     httpGetSubField(http, HTTP_FIELD_WWW_AUTHENTICATE, "nonce", nonce);
 269
 270     httpMD5(cupsUser(), realm, strchr(http->userpass, ':') + 1, encode);
 271     httpMD5Final(nonce, method, resource, encode);
 272     snprintf(digest, sizeof(digest),
 273              "username=\"%s\", realm=\"%s\", nonce=\"%s\", uri=\"%s\", "
 274              "response=\"%s\"", cupsUser(), realm, nonce, resource, encode);
 275     httpSetAuthString(http, "Digest", digest);
 276   }
 277   else
 278   {
 279     DEBUG_printf(("1cupsDoAuthentication: Unknown auth type: \"%s\"",
 280                   http->fields[HTTP_FIELD_WWW_AUTHENTICATE]));
 281     http->status = HTTP_AUTHORIZATION_CANCELED;
 282     return (-1);
 283   }
 284
 285   DEBUG_printf(("1cupsDoAuthentication: authstring=\"%s\"", http->authstring));
 286
 287   return (0);
 288 }
 289
 290
 291 #ifdef HAVE_GSSAPI
 292 /*
 293  * '_cupsSetNegotiateAuthString()' - Set the Kerberos authentication string.
 294  */
 295
 296 int                                     /* O - 0 on success, -1 on error */
 297 _cupsSetNegotiateAuthString(
 298     http_t     *http,                   /* I - Connection to server */
 299     const char *method,                 /* I - Request method ("GET", "POST", "PUT") */
 300     const char *resource)               /* I - Resource path */
 301 {
 302   OM_uint32     minor_status,           /* Minor status code */
 303                 major_status;           /* Major status code */
 304   gss_buffer_desc output_token = GSS_C_EMPTY_BUFFER;
 305                                         /* Output token */
 306
 307
 308   (void)method;
 309   (void)resource;
 310
 311 #  ifdef __APPLE__
 312  /*
 313   * If the weak-linked GSSAPI/Kerberos library is not present, don't try
 314   * to use it...
 315   */
 316
 317   if (gss_init_sec_context == NULL)
 318   {
 319     DEBUG_puts("1_cupsSetNegotiateAuthString: Weak-linked GSSAPI/Kerberos "
 320                "framework is not present");
 321     return (-1);
 322   }
 323 #  endif /* __APPLE__ */
 324
 325   if (http->gssname == GSS_C_NO_NAME)
 326   {
 327     http->gssname = cups_gss_getname(http, _cupsGSSServiceName());
 328   }
 329
 330   if (http->gssctx != GSS_C_NO_CONTEXT)
 331   {
 332     gss_delete_sec_context(&minor_status, &http->gssctx, GSS_C_NO_BUFFER);
 333     http->gssctx = GSS_C_NO_CONTEXT;
 334   }
 335
 336   major_status = gss_init_sec_context(&minor_status, GSS_C_NO_CREDENTIAL,
 337                                       &http->gssctx,
 338                                       http->gssname, http->gssmech,
 339                                       GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG,
 340                                       GSS_C_INDEFINITE,
 341                                       GSS_C_NO_CHANNEL_BINDINGS,
 342                                       GSS_C_NO_BUFFER, &http->gssmech,
 343                                       &output_token, NULL, NULL);
 344
 345 #ifdef HAVE_GSS_ACQUIRE_CRED_EX_F
 346   if (major_status == GSS_S_NO_CRED)
 347   {
 348    /*
 349     * Ask the user for credentials...
 350     */
 351
 352     char                prompt[1024],   /* Prompt for user */
 353                         userbuf[256];   /* Kerberos username */
 354     const char          *username,      /* Username string */
 355                         *password;      /* Password string */
 356     _cups_gss_acquire_t data;           /* Callback data */
 357     gss_auth_identity_desc identity;    /* Kerberos user identity */
 358     _cups_globals_t     *cg = _cupsGlobals();
 359                                         /* Per-thread global data */
 360
 361     if (!cg->lang_default)
 362       cg->lang_default = cupsLangDefault();
 363
 364     snprintf(prompt, sizeof(prompt),
 365              _cupsLangString(cg->lang_default, _("Password for %s on %s? ")),
 366              cupsUser(), http->gsshost);
 367
 368     if ((password = cupsGetPassword2(prompt, http, method, resource)) == NULL)
 369       return (-1);
 370
 371    /*
 372     * Try to acquire credentials...
 373     */
 374
 375     username = cupsUser();
 376     if (!strchr(username, '@'))
 377     {
 378       snprintf(userbuf, sizeof(userbuf), "%s@%s", username, http->gsshost);
 379       username = userbuf;
 380     }
 381
 382     identity.type           = GSS_AUTH_IDENTITY_TYPE_1;
 383     identity.flags          = 0;
 384     identity.username       = (char *)username;
 385     identity.realm          = (char *)"";
 386     identity.password       = (char *)password;
 387     identity.credentialsRef = NULL;
 388
 389     data.sem   = dispatch_semaphore_create(0);
 390     data.major = 0;
 391     data.creds = NULL;
 392
 393     if (data.sem)
 394     {
 395       major_status = gss_acquire_cred_ex_f(NULL, GSS_C_NO_NAME, 0,
 396                                            GSS_C_INDEFINITE, GSS_KRB5_MECHANISM,
 397                                            GSS_C_INITIATE, &identity, &data,
 398                                            cups_gss_acquire);
 399
 400       if (major_status == GSS_S_COMPLETE)
 401       {
 402         dispatch_semaphore_wait(data.sem, DISPATCH_TIME_FOREVER);
 403         major_status = data.major;
 404       }
 405
 406       dispatch_release(data.sem);
 407
 408       if (major_status == GSS_S_COMPLETE)
 409       {
 410         OM_uint32       release_minor;  /* Minor status from releasing creds */
 411
 412         major_status = gss_init_sec_context(&minor_status, data.creds,
 413                                             &http->gssctx,
 414                                             http->gssname, http->gssmech,
 415                                             GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG,
 416                                             GSS_C_INDEFINITE,
 417                                             GSS_C_NO_CHANNEL_BINDINGS,
 418                                             GSS_C_NO_BUFFER, &http->gssmech,
 419                                             &output_token, NULL, NULL);
 420         gss_release_cred(&release_minor, &data.creds);
 421       }
 422     }
 423   }
 424 #endif /* HAVE_GSS_ACQUIRED_CRED_EX_F */
 425
 426   if (GSS_ERROR(major_status))
 427   {
 428     cups_gss_printf(major_status, minor_status,
 429                     "_cupsSetNegotiateAuthString: Unable to initialize "
 430                     "security context");
 431     return (-1);
 432   }
 433
 434 #ifdef DEBUG
 435   else if (major_status == GSS_S_CONTINUE_NEEDED)
 436     cups_gss_printf(major_status, minor_status,
 437                     "_cupsSetNegotiateAuthString: Continuation needed!");
 438 #endif /* DEBUG */
 439
 440   if (output_token.length > 0 && output_token.length <= 65536)
 441   {
 442    /*
 443     * Allocate the authorization string since Windows KDCs can have
 444     * arbitrarily large credentials...
 445     */
 446
 447     int authsize = 10 +                         /* "Negotiate " */
 448                    output_token.length * 4 / 3 + 1 +    /* Base64 */
 449                    1;                                   /* nul */
 450
 451     httpSetAuthString(http, NULL, NULL);
 452
 453     if ((http->authstring = malloc(authsize)) == NULL)
 454     {
 455       http->authstring = http->_authstring;
 456       authsize         = sizeof(http->_authstring);
 457     }
 458
 459     strcpy(http->authstring, "Negotiate ");
 460     httpEncode64_2(http->authstring + 10, authsize - 10, output_token.value,
 461                    output_token.length);
 462
 463     gss_release_buffer(&minor_status, &output_token);
 464   }
 465   else
 466   {
 467     DEBUG_printf(("1_cupsSetNegotiateAuthString: Kerberos credentials too "
 468                   "large - %d bytes!", (int)output_token.length));
 469     gss_release_buffer(&minor_status, &output_token);
 470
 471     return (-1);
 472   }
 473
 474   return (0);
 475 }
 476
 477
 478 #  ifdef HAVE_GSS_ACQUIRE_CRED_EX_F
 479 /*
 480  * 'cups_gss_acquire()' - Kerberos credentials callback.
 481  */
 482 static void
 483 cups_gss_acquire(
 484     void            *ctx,               /* I - Caller context */
 485     OM_uint32       major,              /* I - Major error code */
 486     gss_status_id_t status,             /* I - Status (unused) */
 487     gss_cred_id_t   creds,              /* I - Credentials (if any) */
 488     gss_OID_set     oids,               /* I - Mechanism OIDs (unused) */
 489     OM_uint32       time_rec)           /* I - Timestamp (unused) */
 490 {
 491   uint32_t              min;            /* Minor error code */
 492   _cups_gss_acquire_t   *data;          /* Callback data */
 493
 494
 495   (void)status;
 496   (void)time_rec;
 497
 498   data        = (_cups_gss_acquire_t *)ctx;
 499   data->major = major;
 500   data->creds = creds;
 501
 502   gss_release_oid_set(&min, &oids);
 503   dispatch_semaphore_signal(data->sem);
 504 }
 505 #  endif /* HAVE_GSS_ACQUIRE_CRED_EX_F */
 506
 507
 508 /*
 509  * 'cups_gss_getname()' - Get CUPS service credentials for authentication.
 510  */
 511
 512 static gss_name_t                       /* O - Server name */
 513 cups_gss_getname(
 514     http_t     *http,                   /* I - Connection to server */
 515     const char *service_name)           /* I - Service name */
 516 {
 517   gss_buffer_desc token = GSS_C_EMPTY_BUFFER;
 518                                         /* Service token */
 519   OM_uint32       major_status,         /* Major status code */
 520                   minor_status;         /* Minor status code */
 521   gss_name_t      server_name;          /* Server name */
 522   char            buf[1024];            /* Name buffer */
 523
 524
 525   DEBUG_printf(("7cups_gss_getname(http=%p, service_name=\"%s\")", http,
 526                 service_name));
 527
 528
 529  /*
 530   * Get the hostname...
 531   */
 532
 533   if (!http->gsshost[0])
 534   {
 535     httpGetHostname(http, http->gsshost, sizeof(http->gsshost));
 536
 537     if (!strcmp(http->gsshost, "localhost"))
 538     {
 539       if (gethostname(http->gsshost, sizeof(http->gsshost)) < 0)
 540       {
 541         DEBUG_printf(("1cups_gss_getname: gethostname() failed: %s",
 542                       strerror(errno)));
 543         http->gsshost[0] = '\0';
 544         return (NULL);
 545       }
 546
 547       if (!strchr(http->gsshost, '.'))
 548       {
 549        /*
 550         * The hostname is not a FQDN, so look it up...
 551         */
 552
 553         struct hostent  *host;          /* Host entry to get FQDN */
 554
 555         if ((host = gethostbyname(http->gsshost)) != NULL && host->h_name)
 556         {
 557          /*
 558           * Use the resolved hostname...
 559           */
 560
 561           strlcpy(http->gsshost, host->h_name, sizeof(http->gsshost));
 562         }
 563         else
 564         {
 565           DEBUG_printf(("1cups_gss_getname: gethostbyname(\"%s\") failed.",
 566                         http->gsshost));
 567           http->gsshost[0] = '\0';
 568           return (NULL);
 569         }
 570       }
 571     }
 572   }
 573
 574  /*
 575   * Get a service name we can use for authentication purposes...
 576   */
 577
 578   snprintf(buf, sizeof(buf), "%s@%s", service_name, http->gsshost);
 579
 580   DEBUG_printf(("8cups_gss_getname: Looking up \"%s\".", buf));
 581
 582   token.value  = buf;
 583   token.length = strlen(buf);
 584   server_name  = GSS_C_NO_NAME;
 585   major_status = gss_import_name(&minor_status, &token,
 586                                  GSS_C_NT_HOSTBASED_SERVICE,
 587                                  &server_name);
 588
 589   if (GSS_ERROR(major_status))
 590   {
 591     cups_gss_printf(major_status, minor_status,
 592                     "cups_gss_getname: gss_import_name() failed");
 593     return (NULL);
 594   }
 595
 596   return (server_name);
 597 }
 598
 599
 600 #  ifdef DEBUG
 601 /*
 602  * 'cups_gss_printf()' - Show debug error messages from GSSAPI.
 603  */
 604
 605 static void
 606 cups_gss_printf(OM_uint32  major_status,/* I - Major status code */
 607                 OM_uint32  minor_status,/* I - Minor status code */
 608                 const char *message)    /* I - Prefix for error message */
 609 {
 610   OM_uint32     err_major_status,       /* Major status code for display */
 611                 err_minor_status;       /* Minor status code for display */
 612   OM_uint32     msg_ctx;                /* Message context */
 613   gss_buffer_desc major_status_string = GSS_C_EMPTY_BUFFER,
 614                                         /* Major status message */
 615                 minor_status_string = GSS_C_EMPTY_BUFFER;
 616                                         /* Minor status message */
 617
 618
 619   msg_ctx          = 0;
 620   err_major_status = gss_display_status(&err_minor_status,
 621                                         major_status,
 622                                         GSS_C_GSS_CODE,
 623                                         GSS_C_NO_OID,
 624                                         &msg_ctx,
 625                                         &major_status_string);
 626
 627   if (!GSS_ERROR(err_major_status))
 628     gss_display_status(&err_minor_status, minor_status, GSS_C_MECH_CODE,
 629                        GSS_C_NULL_OID, &msg_ctx, &minor_status_string);
 630
 631   DEBUG_printf(("1%s: %s, %s", message, (char *)major_status_string.value,
 632                 (char *)minor_status_string.value));
 633
 634   gss_release_buffer(&err_minor_status, &major_status_string);
 635   gss_release_buffer(&err_minor_status, &minor_status_string);
 636 }
 637 #  endif /* DEBUG */
 638 #endif /* HAVE_GSSAPI */
 639
 640
 641 /*
 642  * 'cups_local_auth()' - Get the local authorization certificate if
 643  *                       available/applicable.
 644  */
 645
 646 static int                              /* O - 0 if available */
 647                                         /*     1 if not available */
 648                                         /*    -1 error */
 649 cups_local_auth(http_t *http)           /* I - HTTP connection to server */
 650 {
 651 #if defined(WIN32) || defined(__EMX__)
 652  /*
 653   * Currently WIN32 and OS-2 do not support the CUPS server...
 654   */
 655
 656   return (1);
 657 #else
 658   int                   pid;            /* Current process ID */
 659   FILE                  *fp;            /* Certificate file */
 660   char                  trc[16],        /* Try Root Certificate parameter */
 661                         filename[1024], /* Certificate filename */
 662                         certificate[33];/* Certificate string */
 663   _cups_globals_t *cg = _cupsGlobals(); /* Global data */
 664 #  if defined(HAVE_AUTHORIZATION_H)
 665   OSStatus              status;         /* Status */
 666   AuthorizationItem     auth_right;     /* Authorization right */
 667   AuthorizationRights   auth_rights;    /* Authorization rights */
 668   AuthorizationFlags    auth_flags;     /* Authorization flags */
 669   AuthorizationExternalForm auth_extrn; /* Authorization ref external */
 670   char                  auth_key[1024]; /* Buffer */
 671   char                  buffer[1024];   /* Buffer */
 672 #  endif /* HAVE_AUTHORIZATION_H */
 673
 674
 675   DEBUG_printf(("7cups_local_auth(http=%p) hostaddr=%s, hostname=\"%s\"",
 676                 http, httpAddrString(http->hostaddr, filename, sizeof(filename)), http->hostname));
 677
 678  /*
 679   * See if we are accessing localhost...
 680   */
 681
 682   if (!httpAddrLocalhost(http->hostaddr) &&
 683       _cups_strcasecmp(http->hostname, "localhost") != 0)
 684   {
 685     DEBUG_puts("8cups_local_auth: Not a local connection!");
 686     return (1);
 687   }
 688
 689 #  if defined(HAVE_AUTHORIZATION_H)
 690  /*
 691   * Delete any previous authorization reference...
 692   */
 693
 694   if (http->auth_ref)
 695   {
 696     AuthorizationFree(http->auth_ref, kAuthorizationFlagDefaults);
 697     http->auth_ref = NULL;
 698   }
 699
 700   if (!getenv("GATEWAY_INTERFACE") &&
 701       httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "authkey",
 702                        auth_key, sizeof(auth_key)))
 703   {
 704     status = AuthorizationCreate(NULL, kAuthorizationEmptyEnvironment,
 705                                  kAuthorizationFlagDefaults, &http->auth_ref);
 706     if (status != errAuthorizationSuccess)
 707     {
 708       DEBUG_printf(("8cups_local_auth: AuthorizationCreate() returned %d (%s)",
 709                     (int)status, cssmErrorString(status)));
 710       return (-1);
 711     }
 712
 713     auth_right.name        = auth_key;
 714     auth_right.valueLength = 0;
 715     auth_right.value       = NULL;
 716     auth_right.flags       = 0;
 717
 718     auth_rights.count = 1;
 719     auth_rights.items = &auth_right;
 720
 721     auth_flags = kAuthorizationFlagDefaults |
 722                  kAuthorizationFlagPreAuthorize |
 723                  kAuthorizationFlagInteractionAllowed |
 724                  kAuthorizationFlagExtendRights;
 725
 726     status = AuthorizationCopyRights(http->auth_ref, &auth_rights,
 727                                      kAuthorizationEmptyEnvironment,
 728                                      auth_flags, NULL);
 729     if (status == errAuthorizationSuccess)
 730       status = AuthorizationMakeExternalForm(http->auth_ref, &auth_extrn);
 731
 732     if (status == errAuthorizationSuccess)
 733     {
 734      /*
 735       * Set the authorization string and return...
 736       */
 737
 738       httpEncode64_2(buffer, sizeof(buffer), (void *)&auth_extrn,
 739                      sizeof(auth_extrn));
 740
 741       httpSetAuthString(http, "AuthRef", buffer);
 742
 743       DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
 744                     http->authstring));
 745       return (0);
 746     }
 747     else if (status == errAuthorizationCanceled)
 748       return (-1);
 749
 750     DEBUG_printf(("9cups_local_auth: AuthorizationCopyRights() returned %d (%s)",
 751                   (int)status, cssmErrorString(status)));
 752
 753   /*
 754    * Fall through to try certificates...
 755    */
 756   }
 757 #  endif /* HAVE_AUTHORIZATION_H */
 758
 759 #  if defined(SO_PEERCRED) && defined(AF_LOCAL)
 760  /*
 761   * See if we can authenticate using the peer credentials provided over a
 762   * domain socket; if so, specify "PeerCred username" as the authentication
 763   * information...
 764   */
 765
 766   if (
 767 #    ifdef HAVE_GSSAPI
 768       strncmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE], "Negotiate", 9) &&
 769 #    endif /* HAVE_GSSAPI */
 770 #    ifdef HAVE_AUTHORIZATION_H
 771       !httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "authkey",
 772                         auth_key, sizeof(auth_key)) &&
 773 #    endif /* HAVE_AUTHORIZATION_H */
 774       http->hostaddr->addr.sa_family == AF_LOCAL &&
 775       !getenv("GATEWAY_INTERFACE"))     /* Not via CGI programs... */
 776   {
 777    /*
 778     * Verify that the current cupsUser() matches the current UID...
 779     */
 780
 781     struct passwd       *pwd;           /* Password information */
 782     const char          *username;      /* Current username */
 783
 784     username = cupsUser();
 785
 786     if ((pwd = getpwnam(username)) != NULL && pwd->pw_uid == getuid())
 787     {
 788       httpSetAuthString(http, "PeerCred", username);
 789
 790       DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
 791                     http->authstring));
 792
 793       return (0);
 794     }
 795   }
 796 #  endif /* SO_PEERCRED && AF_LOCAL */
 797
 798  /*
 799   * Try opening a certificate file for this PID.  If that fails,
 800   * try the root certificate...
 801   */
 802
 803   pid = getpid();
 804   snprintf(filename, sizeof(filename), "%s/certs/%d", cg->cups_statedir, pid);
 805   if ((fp = fopen(filename, "r")) == NULL && pid > 0)
 806   {
 807    /*
 808     * No certificate for this PID; see if we can get the root certificate...
 809     */
 810
 811     DEBUG_printf(("9cups_local_auth: Unable to open file %s: %s",
 812                   filename, strerror(errno)));
 813
 814 #  ifdef HAVE_GSSAPI
 815     if (!strncmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE], "Negotiate", 9))
 816     {
 817      /*
 818       * Kerberos required, don't try the root certificate...
 819       */
 820
 821       return (1);
 822     }
 823 #  endif /* HAVE_GSSAPI */
 824
 825 #  ifdef HAVE_AUTHORIZATION_H
 826     if (httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "authkey",
 827                          auth_key, sizeof(auth_key)))
 828     {
 829      /*
 830       * Don't use the root certificate as a replacement for an authkey...
 831       */
 832
 833       return (1);
 834     }
 835 #  endif /* HAVE_AUTHORIZATION_H */
 836     if (!httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "trc", trc,
 837                           sizeof(trc)))
 838     {
 839      /*
 840       * Scheduler doesn't want us to use the root certificate...
 841       */
 842
 843       return (1);
 844     }
 845
 846     snprintf(filename, sizeof(filename), "%s/certs/0", cg->cups_statedir);
 847     fp = fopen(filename, "r");
 848   }
 849
 850   if (fp)
 851   {
 852    /*
 853     * Read the certificate from the file...
 854     */
 855
 856     fgets(certificate, sizeof(certificate), fp);
 857     fclose(fp);
 858
 859    /*
 860     * Set the authorization string and return...
 861     */
 862
 863     httpSetAuthString(http, "Local", certificate);
 864
 865     DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
 866                   http->authstring));
 867
 868     return (0);
 869   }
 870
 871   return (1);
 872 #endif /* WIN32 || __EMX__ */
 873 }
 874
 875
 876 /*
 877  * End of "$Id: auth.c 7720 2008-07-11 22:46:21Z mike $".
 878  */