cups/auth.c

   1 /*
   2  * "$Id$"
   3  *
   4  *   Authentication functions for CUPS.
   5  *
   6  *   Copyright 2007-2013 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_STATUS_UNAUTHORIZED@
 116  * status, prior to resubmitting your request.
 117  *
 118  * @since CUPS 1.1.20/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                 *www_auth;              /* WWW-Authenticate header */
 129   char          prompt[1024],           /* Prompt for user */
 130                 realm[HTTP_MAX_VALUE],  /* realm="xyz" string */
 131                 nonce[HTTP_MAX_VALUE];  /* nonce="xyz" string */
 132   int           localauth;              /* Local authentication result */
 133   _cups_globals_t *cg;                  /* Global data */
 134
 135
 136   DEBUG_printf(("cupsDoAuthentication(http=%p, method=\"%s\", resource=\"%s\")",
 137                 http, method, resource));
 138
 139   if (!http)
 140     http = _cupsConnect();
 141
 142   if (!http || !method || !resource)
 143     return (-1);
 144
 145   DEBUG_printf(("2cupsDoAuthentication: digest_tries=%d, userpass=\"%s\"",
 146                 http->digest_tries, http->userpass));
 147   DEBUG_printf(("2cupsDoAuthentication: WWW-Authenticate=\"%s\"",
 148                 httpGetField(http, HTTP_FIELD_WWW_AUTHENTICATE)));
 149
 150  /*
 151   * Clear the current authentication string...
 152   */
 153
 154   httpSetAuthString(http, NULL, NULL);
 155
 156  /*
 157   * See if we can do local authentication...
 158   */
 159
 160   if (http->digest_tries < 3)
 161   {
 162     if ((localauth = cups_local_auth(http)) == 0)
 163     {
 164       DEBUG_printf(("2cupsDoAuthentication: authstring=\"%s\"",
 165                     http->authstring));
 166
 167       if (http->status == HTTP_STATUS_UNAUTHORIZED)
 168         http->digest_tries ++;
 169
 170       return (0);
 171     }
 172     else if (localauth == -1)
 173     {
 174       http->status = HTTP_STATUS_CUPS_AUTHORIZATION_CANCELED;
 175       return (-1);                      /* Error or canceled */
 176     }
 177   }
 178
 179  /*
 180   * Nope, see if we should retry the current username:password...
 181   */
 182
 183   www_auth = http->fields[HTTP_FIELD_WWW_AUTHENTICATE];
 184
 185   if ((http->digest_tries > 1 || !http->userpass[0]) &&
 186       (!_cups_strncasecmp(www_auth, "Basic", 5) ||
 187        !_cups_strncasecmp(www_auth, "Digest", 6)))
 188   {
 189    /*
 190     * Nope - get a new password from the user...
 191     */
 192
 193     char default_username[HTTP_MAX_VALUE];
 194                                         /* Default username */
 195
 196     cg = _cupsGlobals();
 197
 198     if (!cg->lang_default)
 199       cg->lang_default = cupsLangDefault();
 200
 201     if (httpGetSubField(http, HTTP_FIELD_WWW_AUTHENTICATE, "username",
 202                         default_username))
 203       cupsSetUser(default_username);
 204
 205     snprintf(prompt, sizeof(prompt),
 206              _cupsLangString(cg->lang_default, _("Password for %s on %s? ")),
 207              cupsUser(),
 208              http->hostname[0] == '/' ? "localhost" : http->hostname);
 209
 210     http->digest_tries  = _cups_strncasecmp(www_auth, "Digest", 6) != 0;
 211     http->userpass[0]   = '\0';
 212
 213     if ((password = cupsGetPassword2(prompt, http, method, resource)) == NULL)
 214     {
 215       http->status = HTTP_STATUS_CUPS_AUTHORIZATION_CANCELED;
 216       return (-1);
 217     }
 218
 219     snprintf(http->userpass, sizeof(http->userpass), "%s:%s", cupsUser(),
 220              password);
 221   }
 222   else if (http->status == HTTP_STATUS_UNAUTHORIZED)
 223     http->digest_tries ++;
 224
 225   if (http->status == HTTP_STATUS_UNAUTHORIZED && http->digest_tries >= 3)
 226   {
 227     DEBUG_printf(("1cupsDoAuthentication: Too many authentication tries (%d)",
 228                   http->digest_tries));
 229
 230     http->status = HTTP_STATUS_CUPS_AUTHORIZATION_CANCELED;
 231     return (-1);
 232   }
 233
 234  /*
 235   * Got a password; encode it for the server...
 236   */
 237
 238 #ifdef HAVE_GSSAPI
 239   if (!_cups_strncasecmp(www_auth, "Negotiate", 9))
 240   {
 241    /*
 242     * Kerberos authentication...
 243     */
 244
 245     if (_cupsSetNegotiateAuthString(http, method, resource))
 246     {
 247       http->status = HTTP_STATUS_CUPS_AUTHORIZATION_CANCELED;
 248       return (-1);
 249     }
 250   }
 251   else
 252 #endif /* HAVE_GSSAPI */
 253   if (!_cups_strncasecmp(www_auth, "Basic", 5))
 254   {
 255    /*
 256     * Basic authentication...
 257     */
 258
 259     char        encode[256];            /* Base64 buffer */
 260
 261
 262     httpEncode64_2(encode, sizeof(encode), http->userpass,
 263                    (int)strlen(http->userpass));
 264     httpSetAuthString(http, "Basic", encode);
 265   }
 266   else if (!_cups_strncasecmp(www_auth, "Digest", 6))
 267   {
 268    /*
 269     * Digest authentication...
 270     */
 271
 272     char        encode[33],             /* MD5 buffer */
 273                 digest[1024];           /* Digest auth data */
 274
 275
 276     httpGetSubField(http, HTTP_FIELD_WWW_AUTHENTICATE, "realm", realm);
 277     httpGetSubField(http, HTTP_FIELD_WWW_AUTHENTICATE, "nonce", nonce);
 278
 279     httpMD5(cupsUser(), realm, strchr(http->userpass, ':') + 1, encode);
 280     httpMD5Final(nonce, method, resource, encode);
 281     snprintf(digest, sizeof(digest),
 282              "username=\"%s\", realm=\"%s\", nonce=\"%s\", uri=\"%s\", "
 283              "response=\"%s\"", cupsUser(), realm, nonce, resource, encode);
 284     httpSetAuthString(http, "Digest", digest);
 285   }
 286   else
 287   {
 288     DEBUG_printf(("1cupsDoAuthentication: Unknown auth type: \"%s\"",
 289                   www_auth));
 290     http->status = HTTP_STATUS_CUPS_AUTHORIZATION_CANCELED;
 291     return (-1);
 292   }
 293
 294   DEBUG_printf(("1cupsDoAuthentication: authstring=\"%s\"", http->authstring));
 295
 296   return (0);
 297 }
 298
 299
 300 #ifdef HAVE_GSSAPI
 301 /*
 302  * '_cupsSetNegotiateAuthString()' - Set the Kerberos authentication string.
 303  */
 304
 305 int                                     /* O - 0 on success, -1 on error */
 306 _cupsSetNegotiateAuthString(
 307     http_t     *http,                   /* I - Connection to server */
 308     const char *method,                 /* I - Request method ("GET", "POST", "PUT") */
 309     const char *resource)               /* I - Resource path */
 310 {
 311   OM_uint32     minor_status,           /* Minor status code */
 312                 major_status;           /* Major status code */
 313   gss_buffer_desc output_token = GSS_C_EMPTY_BUFFER;
 314                                         /* Output token */
 315
 316
 317   (void)method;
 318   (void)resource;
 319
 320 #  ifdef __APPLE__
 321  /*
 322   * If the weak-linked GSSAPI/Kerberos library is not present, don't try
 323   * to use it...
 324   */
 325
 326   if (gss_init_sec_context == NULL)
 327   {
 328     DEBUG_puts("1_cupsSetNegotiateAuthString: Weak-linked GSSAPI/Kerberos "
 329                "framework is not present");
 330     return (-1);
 331   }
 332 #  endif /* __APPLE__ */
 333
 334   if (http->gssname == GSS_C_NO_NAME)
 335   {
 336     http->gssname = cups_gss_getname(http, _cupsGSSServiceName());
 337   }
 338
 339   if (http->gssctx != GSS_C_NO_CONTEXT)
 340   {
 341     gss_delete_sec_context(&minor_status, &http->gssctx, GSS_C_NO_BUFFER);
 342     http->gssctx = GSS_C_NO_CONTEXT;
 343   }
 344
 345   major_status = gss_init_sec_context(&minor_status, GSS_C_NO_CREDENTIAL,
 346                                       &http->gssctx,
 347                                       http->gssname, http->gssmech,
 348                                       GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG,
 349                                       GSS_C_INDEFINITE,
 350                                       GSS_C_NO_CHANNEL_BINDINGS,
 351                                       GSS_C_NO_BUFFER, &http->gssmech,
 352                                       &output_token, NULL, NULL);
 353
 354 #ifdef HAVE_GSS_ACQUIRE_CRED_EX_F
 355   if (major_status == GSS_S_NO_CRED)
 356   {
 357    /*
 358     * Ask the user for credentials...
 359     */
 360
 361     char                prompt[1024],   /* Prompt for user */
 362                         userbuf[256];   /* Kerberos username */
 363     const char          *username,      /* Username string */
 364                         *password;      /* Password string */
 365     _cups_gss_acquire_t data;           /* Callback data */
 366     gss_auth_identity_desc identity;    /* Kerberos user identity */
 367     _cups_globals_t     *cg = _cupsGlobals();
 368                                         /* Per-thread global data */
 369
 370     if (!cg->lang_default)
 371       cg->lang_default = cupsLangDefault();
 372
 373     snprintf(prompt, sizeof(prompt),
 374              _cupsLangString(cg->lang_default, _("Password for %s on %s? ")),
 375              cupsUser(), http->gsshost);
 376
 377     if ((password = cupsGetPassword2(prompt, http, method, resource)) == NULL)
 378       return (-1);
 379
 380    /*
 381     * Try to acquire credentials...
 382     */
 383
 384     username = cupsUser();
 385     if (!strchr(username, '@'))
 386     {
 387       snprintf(userbuf, sizeof(userbuf), "%s@%s", username, http->gsshost);
 388       username = userbuf;
 389     }
 390
 391     identity.type           = GSS_AUTH_IDENTITY_TYPE_1;
 392     identity.flags          = 0;
 393     identity.username       = (char *)username;
 394     identity.realm          = (char *)"";
 395     identity.password       = (char *)password;
 396     identity.credentialsRef = NULL;
 397
 398     data.sem   = dispatch_semaphore_create(0);
 399     data.major = 0;
 400     data.creds = NULL;
 401
 402     if (data.sem)
 403     {
 404       major_status = gss_acquire_cred_ex_f(NULL, GSS_C_NO_NAME, 0,
 405                                            GSS_C_INDEFINITE, GSS_KRB5_MECHANISM,
 406                                            GSS_C_INITIATE, &identity, &data,
 407                                            cups_gss_acquire);
 408
 409       if (major_status == GSS_S_COMPLETE)
 410       {
 411         dispatch_semaphore_wait(data.sem, DISPATCH_TIME_FOREVER);
 412         major_status = data.major;
 413       }
 414
 415       dispatch_release(data.sem);
 416
 417       if (major_status == GSS_S_COMPLETE)
 418       {
 419         OM_uint32       release_minor;  /* Minor status from releasing creds */
 420
 421         major_status = gss_init_sec_context(&minor_status, data.creds,
 422                                             &http->gssctx,
 423                                             http->gssname, http->gssmech,
 424                                             GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG,
 425                                             GSS_C_INDEFINITE,
 426                                             GSS_C_NO_CHANNEL_BINDINGS,
 427                                             GSS_C_NO_BUFFER, &http->gssmech,
 428                                             &output_token, NULL, NULL);
 429         gss_release_cred(&release_minor, &data.creds);
 430       }
 431     }
 432   }
 433 #endif /* HAVE_GSS_ACQUIRED_CRED_EX_F */
 434
 435   if (GSS_ERROR(major_status))
 436   {
 437     cups_gss_printf(major_status, minor_status,
 438                     "_cupsSetNegotiateAuthString: Unable to initialize "
 439                     "security context");
 440     return (-1);
 441   }
 442
 443 #ifdef DEBUG
 444   else if (major_status == GSS_S_CONTINUE_NEEDED)
 445     cups_gss_printf(major_status, minor_status,
 446                     "_cupsSetNegotiateAuthString: Continuation needed!");
 447 #endif /* DEBUG */
 448
 449   if (output_token.length > 0 && output_token.length <= 65536)
 450   {
 451    /*
 452     * Allocate the authorization string since Windows KDCs can have
 453     * arbitrarily large credentials...
 454     */
 455
 456     int authsize = 10 +                         /* "Negotiate " */
 457                    output_token.length * 4 / 3 + 1 +    /* Base64 */
 458                    1;                                   /* nul */
 459
 460     httpSetAuthString(http, NULL, NULL);
 461
 462     if ((http->authstring = malloc(authsize)) == NULL)
 463     {
 464       http->authstring = http->_authstring;
 465       authsize         = sizeof(http->_authstring);
 466     }
 467
 468     strlcpy(http->authstring, "Negotiate ", authsize);
 469     httpEncode64_2(http->authstring + 10, authsize - 10, output_token.value,
 470                    output_token.length);
 471
 472     gss_release_buffer(&minor_status, &output_token);
 473   }
 474   else
 475   {
 476     DEBUG_printf(("1_cupsSetNegotiateAuthString: Kerberos credentials too "
 477                   "large - %d bytes!", (int)output_token.length));
 478     gss_release_buffer(&minor_status, &output_token);
 479
 480     return (-1);
 481   }
 482
 483   return (0);
 484 }
 485
 486
 487 #  ifdef HAVE_GSS_ACQUIRE_CRED_EX_F
 488 /*
 489  * 'cups_gss_acquire()' - Kerberos credentials callback.
 490  */
 491 static void
 492 cups_gss_acquire(
 493     void            *ctx,               /* I - Caller context */
 494     OM_uint32       major,              /* I - Major error code */
 495     gss_status_id_t status,             /* I - Status (unused) */
 496     gss_cred_id_t   creds,              /* I - Credentials (if any) */
 497     gss_OID_set     oids,               /* I - Mechanism OIDs (unused) */
 498     OM_uint32       time_rec)           /* I - Timestamp (unused) */
 499 {
 500   uint32_t              min;            /* Minor error code */
 501   _cups_gss_acquire_t   *data;          /* Callback data */
 502
 503
 504   (void)status;
 505   (void)time_rec;
 506
 507   data        = (_cups_gss_acquire_t *)ctx;
 508   data->major = major;
 509   data->creds = creds;
 510
 511   gss_release_oid_set(&min, &oids);
 512   dispatch_semaphore_signal(data->sem);
 513 }
 514 #  endif /* HAVE_GSS_ACQUIRE_CRED_EX_F */
 515
 516
 517 /*
 518  * 'cups_gss_getname()' - Get CUPS service credentials for authentication.
 519  */
 520
 521 static gss_name_t                       /* O - Server name */
 522 cups_gss_getname(
 523     http_t     *http,                   /* I - Connection to server */
 524     const char *service_name)           /* I - Service name */
 525 {
 526   gss_buffer_desc token = GSS_C_EMPTY_BUFFER;
 527                                         /* Service token */
 528   OM_uint32       major_status,         /* Major status code */
 529                   minor_status;         /* Minor status code */
 530   gss_name_t      server_name;          /* Server name */
 531   char            buf[1024];            /* Name buffer */
 532
 533
 534   DEBUG_printf(("7cups_gss_getname(http=%p, service_name=\"%s\")", http,
 535                 service_name));
 536
 537
 538  /*
 539   * Get the hostname...
 540   */
 541
 542   if (!http->gsshost[0])
 543   {
 544     httpGetHostname(http, http->gsshost, sizeof(http->gsshost));
 545
 546     if (!strcmp(http->gsshost, "localhost"))
 547     {
 548       if (gethostname(http->gsshost, sizeof(http->gsshost)) < 0)
 549       {
 550         DEBUG_printf(("1cups_gss_getname: gethostname() failed: %s",
 551                       strerror(errno)));
 552         http->gsshost[0] = '\0';
 553         return (NULL);
 554       }
 555
 556       if (!strchr(http->gsshost, '.'))
 557       {
 558        /*
 559         * The hostname is not a FQDN, so look it up...
 560         */
 561
 562         struct hostent  *host;          /* Host entry to get FQDN */
 563
 564         if ((host = gethostbyname(http->gsshost)) != NULL && host->h_name)
 565         {
 566          /*
 567           * Use the resolved hostname...
 568           */
 569
 570           strlcpy(http->gsshost, host->h_name, sizeof(http->gsshost));
 571         }
 572         else
 573         {
 574           DEBUG_printf(("1cups_gss_getname: gethostbyname(\"%s\") failed.",
 575                         http->gsshost));
 576           http->gsshost[0] = '\0';
 577           return (NULL);
 578         }
 579       }
 580     }
 581   }
 582
 583  /*
 584   * Get a service name we can use for authentication purposes...
 585   */
 586
 587   snprintf(buf, sizeof(buf), "%s@%s", service_name, http->gsshost);
 588
 589   DEBUG_printf(("8cups_gss_getname: Looking up \"%s\".", buf));
 590
 591   token.value  = buf;
 592   token.length = strlen(buf);
 593   server_name  = GSS_C_NO_NAME;
 594   major_status = gss_import_name(&minor_status, &token,
 595                                  GSS_C_NT_HOSTBASED_SERVICE,
 596                                  &server_name);
 597
 598   if (GSS_ERROR(major_status))
 599   {
 600     cups_gss_printf(major_status, minor_status,
 601                     "cups_gss_getname: gss_import_name() failed");
 602     return (NULL);
 603   }
 604
 605   return (server_name);
 606 }
 607
 608
 609 #  ifdef DEBUG
 610 /*
 611  * 'cups_gss_printf()' - Show debug error messages from GSSAPI.
 612  */
 613
 614 static void
 615 cups_gss_printf(OM_uint32  major_status,/* I - Major status code */
 616                 OM_uint32  minor_status,/* I - Minor status code */
 617                 const char *message)    /* I - Prefix for error message */
 618 {
 619   OM_uint32     err_major_status,       /* Major status code for display */
 620                 err_minor_status;       /* Minor status code for display */
 621   OM_uint32     msg_ctx;                /* Message context */
 622   gss_buffer_desc major_status_string = GSS_C_EMPTY_BUFFER,
 623                                         /* Major status message */
 624                 minor_status_string = GSS_C_EMPTY_BUFFER;
 625                                         /* Minor status message */
 626
 627
 628   msg_ctx          = 0;
 629   err_major_status = gss_display_status(&err_minor_status,
 630                                         major_status,
 631                                         GSS_C_GSS_CODE,
 632                                         GSS_C_NO_OID,
 633                                         &msg_ctx,
 634                                         &major_status_string);
 635
 636   if (!GSS_ERROR(err_major_status))
 637     gss_display_status(&err_minor_status, minor_status, GSS_C_MECH_CODE,
 638                        GSS_C_NULL_OID, &msg_ctx, &minor_status_string);
 639
 640   DEBUG_printf(("1%s: %s, %s", message, (char *)major_status_string.value,
 641                 (char *)minor_status_string.value));
 642
 643   gss_release_buffer(&err_minor_status, &major_status_string);
 644   gss_release_buffer(&err_minor_status, &minor_status_string);
 645 }
 646 #  endif /* DEBUG */
 647 #endif /* HAVE_GSSAPI */
 648
 649
 650 /*
 651  * 'cups_local_auth()' - Get the local authorization certificate if
 652  *                       available/applicable.
 653  */
 654
 655 static int                              /* O - 0 if available */
 656                                         /*     1 if not available */
 657                                         /*    -1 error */
 658 cups_local_auth(http_t *http)           /* I - HTTP connection to server */
 659 {
 660 #if defined(WIN32) || defined(__EMX__)
 661  /*
 662   * Currently WIN32 and OS-2 do not support the CUPS server...
 663   */
 664
 665   return (1);
 666 #else
 667   int                   pid;            /* Current process ID */
 668   FILE                  *fp;            /* Certificate file */
 669   char                  trc[16],        /* Try Root Certificate parameter */
 670                         filename[1024]; /* Certificate filename */
 671   _cups_globals_t *cg = _cupsGlobals(); /* Global data */
 672 #  if defined(HAVE_AUTHORIZATION_H)
 673   OSStatus              status;         /* Status */
 674   AuthorizationItem     auth_right;     /* Authorization right */
 675   AuthorizationRights   auth_rights;    /* Authorization rights */
 676   AuthorizationFlags    auth_flags;     /* Authorization flags */
 677   AuthorizationExternalForm auth_extrn; /* Authorization ref external */
 678   char                  auth_key[1024]; /* Buffer */
 679   char                  buffer[1024];   /* Buffer */
 680 #  endif /* HAVE_AUTHORIZATION_H */
 681
 682
 683   DEBUG_printf(("7cups_local_auth(http=%p) hostaddr=%s, hostname=\"%s\"",
 684                 http, httpAddrString(http->hostaddr, filename, sizeof(filename)), http->hostname));
 685
 686  /*
 687   * See if we are accessing localhost...
 688   */
 689
 690   if (!httpAddrLocalhost(http->hostaddr) &&
 691       _cups_strcasecmp(http->hostname, "localhost") != 0)
 692   {
 693     DEBUG_puts("8cups_local_auth: Not a local connection!");
 694     return (1);
 695   }
 696
 697 #  if defined(HAVE_AUTHORIZATION_H)
 698  /*
 699   * Delete any previous authorization reference...
 700   */
 701
 702   if (http->auth_ref)
 703   {
 704     AuthorizationFree(http->auth_ref, kAuthorizationFlagDefaults);
 705     http->auth_ref = NULL;
 706   }
 707
 708   if (!getenv("GATEWAY_INTERFACE") &&
 709       httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "authkey",
 710                        auth_key, sizeof(auth_key)))
 711   {
 712     status = AuthorizationCreate(NULL, kAuthorizationEmptyEnvironment,
 713                                  kAuthorizationFlagDefaults, &http->auth_ref);
 714     if (status != errAuthorizationSuccess)
 715     {
 716       DEBUG_printf(("8cups_local_auth: AuthorizationCreate() returned %d (%s)",
 717                     (int)status, cssmErrorString(status)));
 718       return (-1);
 719     }
 720
 721     auth_right.name        = auth_key;
 722     auth_right.valueLength = 0;
 723     auth_right.value       = NULL;
 724     auth_right.flags       = 0;
 725
 726     auth_rights.count = 1;
 727     auth_rights.items = &auth_right;
 728
 729     auth_flags = kAuthorizationFlagDefaults |
 730                  kAuthorizationFlagPreAuthorize |
 731                  kAuthorizationFlagInteractionAllowed |
 732                  kAuthorizationFlagExtendRights;
 733
 734     status = AuthorizationCopyRights(http->auth_ref, &auth_rights,
 735                                      kAuthorizationEmptyEnvironment,
 736                                      auth_flags, NULL);
 737     if (status == errAuthorizationSuccess)
 738       status = AuthorizationMakeExternalForm(http->auth_ref, &auth_extrn);
 739
 740     if (status == errAuthorizationSuccess)
 741     {
 742      /*
 743       * Set the authorization string and return...
 744       */
 745
 746       httpEncode64_2(buffer, sizeof(buffer), (void *)&auth_extrn,
 747                      sizeof(auth_extrn));
 748
 749       httpSetAuthString(http, "AuthRef", buffer);
 750
 751       DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
 752                     http->authstring));
 753       return (0);
 754     }
 755     else if (status == errAuthorizationCanceled)
 756       return (-1);
 757
 758     DEBUG_printf(("9cups_local_auth: AuthorizationCopyRights() returned %d (%s)",
 759                   (int)status, cssmErrorString(status)));
 760
 761   /*
 762    * Fall through to try certificates...
 763    */
 764   }
 765 #  endif /* HAVE_AUTHORIZATION_H */
 766
 767 #  if defined(SO_PEERCRED) && defined(AF_LOCAL)
 768  /*
 769   * See if we can authenticate using the peer credentials provided over a
 770   * domain socket; if so, specify "PeerCred username" as the authentication
 771   * information...
 772   */
 773
 774   if (
 775 #    ifdef HAVE_GSSAPI
 776       strncmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE], "Negotiate", 9) &&
 777 #    endif /* HAVE_GSSAPI */
 778 #    ifdef HAVE_AUTHORIZATION_H
 779       !httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "authkey",
 780                         auth_key, sizeof(auth_key)) &&
 781 #    endif /* HAVE_AUTHORIZATION_H */
 782       http->hostaddr->addr.sa_family == AF_LOCAL &&
 783       !getenv("GATEWAY_INTERFACE"))     /* Not via CGI programs... */
 784   {
 785    /*
 786     * Verify that the current cupsUser() matches the current UID...
 787     */
 788
 789     struct passwd       *pwd;           /* Password information */
 790     const char          *username;      /* Current username */
 791
 792     username = cupsUser();
 793
 794     if ((pwd = getpwnam(username)) != NULL && pwd->pw_uid == getuid())
 795     {
 796       httpSetAuthString(http, "PeerCred", username);
 797
 798       DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
 799                     http->authstring));
 800
 801       return (0);
 802     }
 803   }
 804 #  endif /* SO_PEERCRED && AF_LOCAL */
 805
 806  /*
 807   * Try opening a certificate file for this PID.  If that fails,
 808   * try the root certificate...
 809   */
 810
 811   pid = getpid();
 812   snprintf(filename, sizeof(filename), "%s/certs/%d", cg->cups_statedir, pid);
 813   if ((fp = fopen(filename, "r")) == NULL && pid > 0)
 814   {
 815    /*
 816     * No certificate for this PID; see if we can get the root certificate...
 817     */
 818
 819     DEBUG_printf(("9cups_local_auth: Unable to open file %s: %s",
 820                   filename, strerror(errno)));
 821
 822 #  ifdef HAVE_GSSAPI
 823     if (!strncmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE], "Negotiate", 9))
 824     {
 825      /*
 826       * Kerberos required, don't try the root certificate...
 827       */
 828
 829       return (1);
 830     }
 831 #  endif /* HAVE_GSSAPI */
 832
 833 #  ifdef HAVE_AUTHORIZATION_H
 834     if (httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "authkey",
 835                          auth_key, sizeof(auth_key)))
 836     {
 837      /*
 838       * Don't use the root certificate as a replacement for an authkey...
 839       */
 840
 841       return (1);
 842     }
 843 #  endif /* HAVE_AUTHORIZATION_H */
 844     if (!httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "trc", trc,
 845                           sizeof(trc)))
 846     {
 847      /*
 848       * Scheduler doesn't want us to use the root certificate...
 849       */
 850
 851       return (1);
 852     }
 853
 854     snprintf(filename, sizeof(filename), "%s/certs/0", cg->cups_statedir);
 855     fp = fopen(filename, "r");
 856   }
 857
 858   if (fp)
 859   {
 860    /*
 861     * Read the certificate from the file...
 862     */
 863
 864     char        certificate[33],        /* Certificate string */
 865                 *certptr;               /* Pointer to certificate string */
 866
 867     certptr = fgets(certificate, sizeof(certificate), fp);
 868     fclose(fp);
 869
 870     if (certptr)
 871     {
 872      /*
 873       * Set the authorization string and return...
 874       */
 875
 876       httpSetAuthString(http, "Local", certificate);
 877
 878       DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
 879                     http->authstring));
 880
 881       return (0);
 882     }
 883   }
 884
 885   return (1);
 886 #endif /* WIN32 || __EMX__ */
 887 }
 888
 889
 890 /*
 891  * End of "$Id$".
 892  */