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      1 /*
      2  * Authentication functions for CUPS.
      3  *
      4  * Copyright 2007-2016 by Apple Inc.
      5  * Copyright 1997-2007 by Easy Software Products.
      6  *
      7  * This file contains Kerberos support code, copyright 2006 by
      8  * Jelmer Vernooij.
      9  *
     10  * These coded instructions, statements, and computer programs are the
     11  * property of Apple Inc. and are protected by Federal copyright
     12  * law.  Distribution and use rights are outlined in the file "LICENSE.txt"
     13  * which should have been included with this file.  If this file is
     14  * missing or damaged, see the license at "http://www.cups.org/".
     15  *
     16  * This file is subject to the Apple OS-Developed Software exception.
     17  */
     18 
     19 /*
     20  * Include necessary headers...
     21  */
     22 
     23 #include "cups-private.h"
     24 #include <fcntl.h>
     25 #include <sys/stat.h>
     26 #if defined(WIN32) || defined(__EMX__)
     27 #  include <io.h>
     28 #else
     29 #  include <unistd.h>
     30 #endif /* WIN32 || __EMX__ */
     31 
     32 #if HAVE_AUTHORIZATION_H
     33 #  include <Security/Authorization.h>
     34 #  ifdef HAVE_SECBASEPRIV_H
     35 #    include <Security/SecBasePriv.h>
     36 #  else
     37 extern const char *cssmErrorString(int error);
     38 #  endif /* HAVE_SECBASEPRIV_H */
     39 #endif /* HAVE_AUTHORIZATION_H */
     40 
     41 #if defined(SO_PEERCRED) && defined(AF_LOCAL)
     42 #  include <pwd.h>
     43 #endif /* SO_PEERCRED && AF_LOCAL */
     44 
     45 
     46 /*
     47  * Local functions...
     48  */
     49 
     50 #ifdef HAVE_GSSAPI
     51 #  ifdef HAVE_GSS_ACQUIRE_CRED_EX_F
     52 #    ifdef HAVE_GSS_GSSAPI_SPI_H
     53 #      include <GSS/gssapi_spi.h>
     54 #    else
     55 #      define GSS_AUTH_IDENTITY_TYPE_1 1
     56 #      define gss_acquire_cred_ex_f __ApplePrivate_gss_acquire_cred_ex_f
     57 typedef struct gss_auth_identity /* @private@ */
     58 {
     59   uint32_t type;
     60   uint32_t flags;
     61   char *username;
     62   char *realm;
     63   char *password;
     64   gss_buffer_t *credentialsRef;
     65 } gss_auth_identity_desc;
     66 extern OM_uint32 gss_acquire_cred_ex_f(gss_status_id_t, const gss_name_t,
     67 				       OM_uint32, OM_uint32, const gss_OID,
     68 				       gss_cred_usage_t, gss_auth_identity_t,
     69 				       void *, void (*)(void *, OM_uint32,
     70 				                        gss_status_id_t,
     71 							gss_cred_id_t,
     72 							gss_OID_set,
     73 							OM_uint32));
     74 #    endif /* HAVE_GSS_GSSAPI_SPI_H */
     75 #    include <dispatch/dispatch.h>
     76 typedef struct _cups_gss_acquire_s	/* Acquire callback data */
     77 {
     78   dispatch_semaphore_t	sem;		/* Synchronization semaphore */
     79   OM_uint32		major;		/* Returned status code */
     80   gss_cred_id_t		creds;		/* Returned credentials */
     81 } _cups_gss_acquire_t;
     82 
     83 static void	cups_gss_acquire(void *ctx, OM_uint32 major,
     84 		                 gss_status_id_t status,
     85 				 gss_cred_id_t creds, gss_OID_set oids,
     86 				 OM_uint32 time_rec);
     87 #  endif /* HAVE_GSS_ACQUIRE_CRED_EX_F */
     88 static gss_name_t cups_gss_getname(http_t *http, const char *service_name);
     89 #  ifdef DEBUG
     90 static void	cups_gss_printf(OM_uint32 major_status, OM_uint32 minor_status,
     91 				const char *message);
     92 #  else
     93 #    define	cups_gss_printf(major, minor, message)
     94 #  endif /* DEBUG */
     95 #endif /* HAVE_GSSAPI */
     96 static int	cups_local_auth(http_t *http);
     97 
     98 
     99 /*
    100  * 'cupsDoAuthentication()' - Authenticate a request.
    101  *
    102  * This function should be called in response to a @code HTTP_STATUS_UNAUTHORIZED@
    103  * status, prior to resubmitting your request.
    104  *
    105  * @since CUPS 1.1.20/macOS 10.4@
    106  */
    107 
    108 int					/* O - 0 on success, -1 on error */
    109 cupsDoAuthentication(
    110     http_t     *http,			/* I - Connection to server or @code CUPS_HTTP_DEFAULT@ */
    111     const char *method,			/* I - Request method ("GET", "POST", "PUT") */
    112     const char *resource)		/* I - Resource path */
    113 {
    114   const char	*password,		/* Password string */
    115 		*www_auth;		/* WWW-Authenticate header */
    116   char		prompt[1024],		/* Prompt for user */
    117 		realm[HTTP_MAX_VALUE],	/* realm="xyz" string */
    118 		nonce[HTTP_MAX_VALUE];	/* nonce="xyz" string */
    119   int		localauth;		/* Local authentication result */
    120   _cups_globals_t *cg;			/* Global data */
    121 
    122 
    123   DEBUG_printf(("cupsDoAuthentication(http=%p, method=\"%s\", resource=\"%s\")", (void *)http, method, resource));
    124 
    125   if (!http)
    126     http = _cupsConnect();
    127 
    128   if (!http || !method || !resource)
    129     return (-1);
    130 
    131   DEBUG_printf(("2cupsDoAuthentication: digest_tries=%d, userpass=\"%s\"",
    132                 http->digest_tries, http->userpass));
    133   DEBUG_printf(("2cupsDoAuthentication: WWW-Authenticate=\"%s\"",
    134                 httpGetField(http, HTTP_FIELD_WWW_AUTHENTICATE)));
    135 
    136  /*
    137   * Clear the current authentication string...
    138   */
    139 
    140   httpSetAuthString(http, NULL, NULL);
    141 
    142  /*
    143   * See if we can do local authentication...
    144   */
    145 
    146   if (http->digest_tries < 3)
    147   {
    148     if ((localauth = cups_local_auth(http)) == 0)
    149     {
    150       DEBUG_printf(("2cupsDoAuthentication: authstring=\"%s\"",
    151                     http->authstring));
    152 
    153       if (http->status == HTTP_STATUS_UNAUTHORIZED)
    154 	http->digest_tries ++;
    155 
    156       return (0);
    157     }
    158     else if (localauth == -1)
    159     {
    160       http->status = HTTP_STATUS_CUPS_AUTHORIZATION_CANCELED;
    161       return (-1);			/* Error or canceled */
    162     }
    163   }
    164 
    165  /*
    166   * Nope, see if we should retry the current username:password...
    167   */
    168 
    169   www_auth = http->fields[HTTP_FIELD_WWW_AUTHENTICATE];
    170 
    171   if ((http->digest_tries > 1 || !http->userpass[0]) &&
    172       (!_cups_strncasecmp(www_auth, "Basic", 5) ||
    173        !_cups_strncasecmp(www_auth, "Digest", 6)))
    174   {
    175    /*
    176     * Nope - get a new password from the user...
    177     */
    178 
    179     char default_username[HTTP_MAX_VALUE];
    180 					/* Default username */
    181 
    182     cg = _cupsGlobals();
    183 
    184     if (!cg->lang_default)
    185       cg->lang_default = cupsLangDefault();
    186 
    187     if (httpGetSubField(http, HTTP_FIELD_WWW_AUTHENTICATE, "username",
    188                         default_username))
    189       cupsSetUser(default_username);
    190 
    191     snprintf(prompt, sizeof(prompt),
    192              _cupsLangString(cg->lang_default, _("Password for %s on %s? ")),
    193 	     cupsUser(),
    194 	     http->hostname[0] == '/' ? "localhost" : http->hostname);
    195 
    196     http->digest_tries  = _cups_strncasecmp(www_auth, "Digest", 6) != 0;
    197     http->userpass[0]   = '\0';
    198 
    199     if ((password = cupsGetPassword2(prompt, http, method, resource)) == NULL)
    200     {
    201       http->status = HTTP_STATUS_CUPS_AUTHORIZATION_CANCELED;
    202       return (-1);
    203     }
    204 
    205     snprintf(http->userpass, sizeof(http->userpass), "%s:%s", cupsUser(),
    206              password);
    207   }
    208   else if (http->status == HTTP_STATUS_UNAUTHORIZED)
    209     http->digest_tries ++;
    210 
    211   if (http->status == HTTP_STATUS_UNAUTHORIZED && http->digest_tries >= 3)
    212   {
    213     DEBUG_printf(("1cupsDoAuthentication: Too many authentication tries (%d)",
    214 		  http->digest_tries));
    215 
    216     http->status = HTTP_STATUS_CUPS_AUTHORIZATION_CANCELED;
    217     return (-1);
    218   }
    219 
    220  /*
    221   * Got a password; encode it for the server...
    222   */
    223 
    224 #ifdef HAVE_GSSAPI
    225   if (!_cups_strncasecmp(www_auth, "Negotiate", 9))
    226   {
    227    /*
    228     * Kerberos authentication...
    229     */
    230 
    231     if (_cupsSetNegotiateAuthString(http, method, resource))
    232     {
    233       http->status = HTTP_STATUS_CUPS_AUTHORIZATION_CANCELED;
    234       return (-1);
    235     }
    236   }
    237   else
    238 #endif /* HAVE_GSSAPI */
    239   if (!_cups_strncasecmp(www_auth, "Basic", 5))
    240   {
    241    /*
    242     * Basic authentication...
    243     */
    244 
    245     char	encode[256];		/* Base64 buffer */
    246 
    247 
    248     httpEncode64_2(encode, sizeof(encode), http->userpass,
    249                    (int)strlen(http->userpass));
    250     httpSetAuthString(http, "Basic", encode);
    251   }
    252   else if (!_cups_strncasecmp(www_auth, "Digest", 6))
    253   {
    254    /*
    255     * Digest authentication...
    256     */
    257 
    258     char	encode[33],		/* MD5 buffer */
    259 		digest[1024];		/* Digest auth data */
    260 
    261     httpGetSubField(http, HTTP_FIELD_WWW_AUTHENTICATE, "realm", realm);
    262     httpGetSubField(http, HTTP_FIELD_WWW_AUTHENTICATE, "nonce", nonce);
    263 
    264     httpMD5(cupsUser(), realm, strchr(http->userpass, ':') + 1, encode);
    265     httpMD5Final(nonce, method, resource, encode);
    266     snprintf(digest, sizeof(digest),
    267 	     "username=\"%s\", realm=\"%s\", nonce=\"%s\", uri=\"%s\", "
    268 	     "response=\"%s\"", cupsUser(), realm, nonce, resource, encode);
    269     httpSetAuthString(http, "Digest", digest);
    270   }
    271   else
    272   {
    273     DEBUG_printf(("1cupsDoAuthentication: Unknown auth type: \"%s\"",
    274                   www_auth));
    275     http->status = HTTP_STATUS_CUPS_AUTHORIZATION_CANCELED;
    276     return (-1);
    277   }
    278 
    279   DEBUG_printf(("1cupsDoAuthentication: authstring=\"%s\"", http->authstring));
    280 
    281   return (0);
    282 }
    283 
    284 
    285 #ifdef HAVE_GSSAPI
    286 /*
    287  * '_cupsSetNegotiateAuthString()' - Set the Kerberos authentication string.
    288  */
    289 
    290 int					/* O - 0 on success, -1 on error */
    291 _cupsSetNegotiateAuthString(
    292     http_t     *http,			/* I - Connection to server */
    293     const char *method,			/* I - Request method ("GET", "POST", "PUT") */
    294     const char *resource)		/* I - Resource path */
    295 {
    296   OM_uint32	minor_status,		/* Minor status code */
    297 		major_status;		/* Major status code */
    298   gss_buffer_desc output_token = GSS_C_EMPTY_BUFFER;
    299 					/* Output token */
    300 
    301 
    302   (void)method;
    303   (void)resource;
    304 
    305 #  ifdef __APPLE__
    306  /*
    307   * If the weak-linked GSSAPI/Kerberos library is not present, don't try
    308   * to use it...
    309   */
    310 
    311   if (&gss_init_sec_context == NULL)
    312   {
    313     DEBUG_puts("1_cupsSetNegotiateAuthString: Weak-linked GSSAPI/Kerberos "
    314                "framework is not present");
    315     return (-1);
    316   }
    317 #  endif /* __APPLE__ */
    318 
    319   if (http->gssname == GSS_C_NO_NAME)
    320   {
    321     http->gssname = cups_gss_getname(http, _cupsGSSServiceName());
    322   }
    323 
    324   if (http->gssctx != GSS_C_NO_CONTEXT)
    325   {
    326     gss_delete_sec_context(&minor_status, &http->gssctx, GSS_C_NO_BUFFER);
    327     http->gssctx = GSS_C_NO_CONTEXT;
    328   }
    329 
    330   major_status = gss_init_sec_context(&minor_status, GSS_C_NO_CREDENTIAL,
    331 				      &http->gssctx,
    332 				      http->gssname, http->gssmech,
    333 				      GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG,
    334 				      GSS_C_INDEFINITE,
    335 				      GSS_C_NO_CHANNEL_BINDINGS,
    336 				      GSS_C_NO_BUFFER, &http->gssmech,
    337 				      &output_token, NULL, NULL);
    338 
    339 #ifdef HAVE_GSS_ACQUIRE_CRED_EX_F
    340   if (major_status == GSS_S_NO_CRED)
    341   {
    342    /*
    343     * Ask the user for credentials...
    344     */
    345 
    346     char		prompt[1024],	/* Prompt for user */
    347 			userbuf[256];	/* Kerberos username */
    348     const char		*username,	/* Username string */
    349 			*password;	/* Password string */
    350     _cups_gss_acquire_t	data;		/* Callback data */
    351     gss_auth_identity_desc identity;	/* Kerberos user identity */
    352     _cups_globals_t	*cg = _cupsGlobals();
    353 					/* Per-thread global data */
    354 
    355     if (!cg->lang_default)
    356       cg->lang_default = cupsLangDefault();
    357 
    358     snprintf(prompt, sizeof(prompt),
    359              _cupsLangString(cg->lang_default, _("Password for %s on %s? ")),
    360 	     cupsUser(), http->gsshost);
    361 
    362     if ((password = cupsGetPassword2(prompt, http, method, resource)) == NULL)
    363       return (-1);
    364 
    365    /*
    366     * Try to acquire credentials...
    367     */
    368 
    369     username = cupsUser();
    370     if (!strchr(username, '@'))
    371     {
    372       snprintf(userbuf, sizeof(userbuf), "%s@%s", username, http->gsshost);
    373       username = userbuf;
    374     }
    375 
    376     identity.type           = GSS_AUTH_IDENTITY_TYPE_1;
    377     identity.flags          = 0;
    378     identity.username       = (char *)username;
    379     identity.realm          = (char *)"";
    380     identity.password       = (char *)password;
    381     identity.credentialsRef = NULL;
    382 
    383     data.sem   = dispatch_semaphore_create(0);
    384     data.major = 0;
    385     data.creds = NULL;
    386 
    387     if (data.sem)
    388     {
    389       major_status = gss_acquire_cred_ex_f(NULL, GSS_C_NO_NAME, 0, GSS_C_INDEFINITE, GSS_KRB5_MECHANISM, GSS_C_INITIATE, (gss_auth_identity_t)&identity, &data, cups_gss_acquire);
    390 
    391       if (major_status == GSS_S_COMPLETE)
    392       {
    393 	dispatch_semaphore_wait(data.sem, DISPATCH_TIME_FOREVER);
    394 	major_status = data.major;
    395       }
    396 
    397       dispatch_release(data.sem);
    398 
    399       if (major_status == GSS_S_COMPLETE)
    400       {
    401         OM_uint32	release_minor;	/* Minor status from releasing creds */
    402 
    403 	major_status = gss_init_sec_context(&minor_status, data.creds,
    404 					    &http->gssctx,
    405 					    http->gssname, http->gssmech,
    406 					    GSS_C_MUTUAL_FLAG | GSS_C_INTEG_FLAG,
    407 					    GSS_C_INDEFINITE,
    408 					    GSS_C_NO_CHANNEL_BINDINGS,
    409 					    GSS_C_NO_BUFFER, &http->gssmech,
    410 					    &output_token, NULL, NULL);
    411         gss_release_cred(&release_minor, &data.creds);
    412       }
    413     }
    414   }
    415 #endif /* HAVE_GSS_ACQUIRED_CRED_EX_F */
    416 
    417   if (GSS_ERROR(major_status))
    418   {
    419     cups_gss_printf(major_status, minor_status,
    420 		    "_cupsSetNegotiateAuthString: Unable to initialize "
    421 		    "security context");
    422     return (-1);
    423   }
    424 
    425 #ifdef DEBUG
    426   else if (major_status == GSS_S_CONTINUE_NEEDED)
    427     cups_gss_printf(major_status, minor_status,
    428 		    "_cupsSetNegotiateAuthString: Continuation needed!");
    429 #endif /* DEBUG */
    430 
    431   if (output_token.length > 0 && output_token.length <= 65536)
    432   {
    433    /*
    434     * Allocate the authorization string since Windows KDCs can have
    435     * arbitrarily large credentials...
    436     */
    437 
    438     int authsize = 10 +			/* "Negotiate " */
    439 		   (int)output_token.length * 4 / 3 + 1 + 1;
    440 		   			/* Base64 + nul */
    441 
    442     httpSetAuthString(http, NULL, NULL);
    443 
    444     if ((http->authstring = malloc((size_t)authsize)) == NULL)
    445     {
    446       http->authstring = http->_authstring;
    447       authsize         = sizeof(http->_authstring);
    448     }
    449 
    450     strlcpy(http->authstring, "Negotiate ", (size_t)authsize);
    451     httpEncode64_2(http->authstring + 10, authsize - 10, output_token.value,
    452 		   (int)output_token.length);
    453 
    454     gss_release_buffer(&minor_status, &output_token);
    455   }
    456   else
    457   {
    458     DEBUG_printf(("1_cupsSetNegotiateAuthString: Kerberos credentials too "
    459                   "large - %d bytes!", (int)output_token.length));
    460     gss_release_buffer(&minor_status, &output_token);
    461 
    462     return (-1);
    463   }
    464 
    465   return (0);
    466 }
    467 
    468 
    469 #  ifdef HAVE_GSS_ACQUIRE_CRED_EX_F
    470 /*
    471  * 'cups_gss_acquire()' - Kerberos credentials callback.
    472  */
    473 static void
    474 cups_gss_acquire(
    475     void            *ctx,		/* I - Caller context */
    476     OM_uint32       major,		/* I - Major error code */
    477     gss_status_id_t status,		/* I - Status (unused) */
    478     gss_cred_id_t   creds,		/* I - Credentials (if any) */
    479     gss_OID_set     oids,		/* I - Mechanism OIDs (unused) */
    480     OM_uint32       time_rec)		/* I - Timestamp (unused) */
    481 {
    482   uint32_t		min;		/* Minor error code */
    483   _cups_gss_acquire_t	*data;		/* Callback data */
    484 
    485 
    486   (void)status;
    487   (void)time_rec;
    488 
    489   data        = (_cups_gss_acquire_t *)ctx;
    490   data->major = major;
    491   data->creds = creds;
    492 
    493   gss_release_oid_set(&min, &oids);
    494   dispatch_semaphore_signal(data->sem);
    495 }
    496 #  endif /* HAVE_GSS_ACQUIRE_CRED_EX_F */
    497 
    498 
    499 /*
    500  * 'cups_gss_getname()' - Get CUPS service credentials for authentication.
    501  */
    502 
    503 static gss_name_t			/* O - Server name */
    504 cups_gss_getname(
    505     http_t     *http,			/* I - Connection to server */
    506     const char *service_name)		/* I - Service name */
    507 {
    508   gss_buffer_desc token = GSS_C_EMPTY_BUFFER;
    509 					/* Service token */
    510   OM_uint32	  major_status,		/* Major status code */
    511 		  minor_status;		/* Minor status code */
    512   gss_name_t	  server_name;		/* Server name */
    513   char		  buf[1024];		/* Name buffer */
    514 
    515 
    516   DEBUG_printf(("7cups_gss_getname(http=%p, service_name=\"%s\")", http,
    517                 service_name));
    518 
    519 
    520  /*
    521   * Get the hostname...
    522   */
    523 
    524   if (!http->gsshost[0])
    525   {
    526     httpGetHostname(http, http->gsshost, sizeof(http->gsshost));
    527 
    528     if (!strcmp(http->gsshost, "localhost"))
    529     {
    530       if (gethostname(http->gsshost, sizeof(http->gsshost)) < 0)
    531       {
    532 	DEBUG_printf(("1cups_gss_getname: gethostname() failed: %s",
    533 		      strerror(errno)));
    534 	http->gsshost[0] = '\0';
    535 	return (NULL);
    536       }
    537 
    538       if (!strchr(http->gsshost, '.'))
    539       {
    540        /*
    541 	* The hostname is not a FQDN, so look it up...
    542 	*/
    543 
    544 	struct hostent	*host;		/* Host entry to get FQDN */
    545 
    546 	if ((host = gethostbyname(http->gsshost)) != NULL && host->h_name)
    547 	{
    548 	 /*
    549 	  * Use the resolved hostname...
    550 	  */
    551 
    552 	  strlcpy(http->gsshost, host->h_name, sizeof(http->gsshost));
    553 	}
    554 	else
    555 	{
    556 	  DEBUG_printf(("1cups_gss_getname: gethostbyname(\"%s\") failed.",
    557 			http->gsshost));
    558 	  http->gsshost[0] = '\0';
    559 	  return (NULL);
    560 	}
    561       }
    562     }
    563   }
    564 
    565  /*
    566   * Get a service name we can use for authentication purposes...
    567   */
    568 
    569   snprintf(buf, sizeof(buf), "%s@%s", service_name, http->gsshost);
    570 
    571   DEBUG_printf(("8cups_gss_getname: Looking up \"%s\".", buf));
    572 
    573   token.value  = buf;
    574   token.length = strlen(buf);
    575   server_name  = GSS_C_NO_NAME;
    576   major_status = gss_import_name(&minor_status, &token,
    577 	 			 GSS_C_NT_HOSTBASED_SERVICE,
    578 				 &server_name);
    579 
    580   if (GSS_ERROR(major_status))
    581   {
    582     cups_gss_printf(major_status, minor_status,
    583                     "cups_gss_getname: gss_import_name() failed");
    584     return (NULL);
    585   }
    586 
    587   return (server_name);
    588 }
    589 
    590 
    591 #  ifdef DEBUG
    592 /*
    593  * 'cups_gss_printf()' - Show debug error messages from GSSAPI.
    594  */
    595 
    596 static void
    597 cups_gss_printf(OM_uint32  major_status,/* I - Major status code */
    598 		OM_uint32  minor_status,/* I - Minor status code */
    599 		const char *message)	/* I - Prefix for error message */
    600 {
    601   OM_uint32	err_major_status,	/* Major status code for display */
    602 		err_minor_status;	/* Minor status code for display */
    603   OM_uint32	msg_ctx;		/* Message context */
    604   gss_buffer_desc major_status_string = GSS_C_EMPTY_BUFFER,
    605 					/* Major status message */
    606 		minor_status_string = GSS_C_EMPTY_BUFFER;
    607 					/* Minor status message */
    608 
    609 
    610   msg_ctx          = 0;
    611   err_major_status = gss_display_status(&err_minor_status,
    612 	                        	major_status,
    613 					GSS_C_GSS_CODE,
    614 					GSS_C_NO_OID,
    615 					&msg_ctx,
    616 					&major_status_string);
    617 
    618   if (!GSS_ERROR(err_major_status))
    619     gss_display_status(&err_minor_status, minor_status, GSS_C_MECH_CODE,
    620 		       GSS_C_NULL_OID, &msg_ctx, &minor_status_string);
    621 
    622   DEBUG_printf(("1%s: %s, %s", message, (char *)major_status_string.value,
    623 	        (char *)minor_status_string.value));
    624 
    625   gss_release_buffer(&err_minor_status, &major_status_string);
    626   gss_release_buffer(&err_minor_status, &minor_status_string);
    627 }
    628 #  endif /* DEBUG */
    629 #endif /* HAVE_GSSAPI */
    630 
    631 
    632 /*
    633  * 'cups_local_auth()' - Get the local authorization certificate if
    634  *                       available/applicable.
    635  */
    636 
    637 static int				/* O - 0 if available */
    638 					/*     1 if not available */
    639 					/*    -1 error */
    640 cups_local_auth(http_t *http)		/* I - HTTP connection to server */
    641 {
    642 #if defined(WIN32) || defined(__EMX__)
    643  /*
    644   * Currently WIN32 and OS-2 do not support the CUPS server...
    645   */
    646 
    647   return (1);
    648 #else
    649   int			pid;		/* Current process ID */
    650   FILE			*fp;		/* Certificate file */
    651   char			trc[16],	/* Try Root Certificate parameter */
    652 			filename[1024];	/* Certificate filename */
    653   _cups_globals_t *cg = _cupsGlobals();	/* Global data */
    654 #  if defined(HAVE_AUTHORIZATION_H)
    655   OSStatus		status;		/* Status */
    656   AuthorizationItem	auth_right;	/* Authorization right */
    657   AuthorizationRights	auth_rights;	/* Authorization rights */
    658   AuthorizationFlags	auth_flags;	/* Authorization flags */
    659   AuthorizationExternalForm auth_extrn;	/* Authorization ref external */
    660   char			auth_key[1024];	/* Buffer */
    661   char			buffer[1024];	/* Buffer */
    662 #  endif /* HAVE_AUTHORIZATION_H */
    663 
    664 
    665   DEBUG_printf(("7cups_local_auth(http=%p) hostaddr=%s, hostname=\"%s\"", (void *)http, httpAddrString(http->hostaddr, filename, sizeof(filename)), http->hostname));
    666 
    667  /*
    668   * See if we are accessing localhost...
    669   */
    670 
    671   if (!httpAddrLocalhost(http->hostaddr) &&
    672       _cups_strcasecmp(http->hostname, "localhost") != 0)
    673   {
    674     DEBUG_puts("8cups_local_auth: Not a local connection!");
    675     return (1);
    676   }
    677 
    678 #  if defined(HAVE_AUTHORIZATION_H)
    679  /*
    680   * Delete any previous authorization reference...
    681   */
    682 
    683   if (http->auth_ref)
    684   {
    685     AuthorizationFree(http->auth_ref, kAuthorizationFlagDefaults);
    686     http->auth_ref = NULL;
    687   }
    688 
    689   if (!getenv("GATEWAY_INTERFACE") &&
    690       httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "authkey",
    691 		       auth_key, sizeof(auth_key)))
    692   {
    693     status = AuthorizationCreate(NULL, kAuthorizationEmptyEnvironment,
    694 				 kAuthorizationFlagDefaults, &http->auth_ref);
    695     if (status != errAuthorizationSuccess)
    696     {
    697       DEBUG_printf(("8cups_local_auth: AuthorizationCreate() returned %d (%s)",
    698 		    (int)status, cssmErrorString(status)));
    699       return (-1);
    700     }
    701 
    702     auth_right.name        = auth_key;
    703     auth_right.valueLength = 0;
    704     auth_right.value       = NULL;
    705     auth_right.flags       = 0;
    706 
    707     auth_rights.count = 1;
    708     auth_rights.items = &auth_right;
    709 
    710     auth_flags = kAuthorizationFlagDefaults |
    711 		 kAuthorizationFlagPreAuthorize |
    712 		 kAuthorizationFlagInteractionAllowed |
    713 		 kAuthorizationFlagExtendRights;
    714 
    715     status = AuthorizationCopyRights(http->auth_ref, &auth_rights,
    716 				     kAuthorizationEmptyEnvironment,
    717 				     auth_flags, NULL);
    718     if (status == errAuthorizationSuccess)
    719       status = AuthorizationMakeExternalForm(http->auth_ref, &auth_extrn);
    720 
    721     if (status == errAuthorizationSuccess)
    722     {
    723      /*
    724       * Set the authorization string and return...
    725       */
    726 
    727       httpEncode64_2(buffer, sizeof(buffer), (void *)&auth_extrn,
    728 		     sizeof(auth_extrn));
    729 
    730       httpSetAuthString(http, "AuthRef", buffer);
    731 
    732       DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
    733 		    http->authstring));
    734       return (0);
    735     }
    736     else if (status == errAuthorizationCanceled)
    737       return (-1);
    738 
    739     DEBUG_printf(("9cups_local_auth: AuthorizationCopyRights() returned %d (%s)",
    740 		  (int)status, cssmErrorString(status)));
    741 
    742   /*
    743    * Fall through to try certificates...
    744    */
    745   }
    746 #  endif /* HAVE_AUTHORIZATION_H */
    747 
    748 #  if defined(SO_PEERCRED) && defined(AF_LOCAL)
    749  /*
    750   * See if we can authenticate using the peer credentials provided over a
    751   * domain socket; if so, specify "PeerCred username" as the authentication
    752   * information...
    753   */
    754 
    755   if (
    756 #    ifdef HAVE_GSSAPI
    757       _cups_strncasecmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE], "Negotiate", 9) &&
    758 #    endif /* HAVE_GSSAPI */
    759 #    ifdef HAVE_AUTHORIZATION_H
    760       !httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "authkey",
    761 		        auth_key, sizeof(auth_key)) &&
    762 #    endif /* HAVE_AUTHORIZATION_H */
    763       http->hostaddr->addr.sa_family == AF_LOCAL &&
    764       !getenv("GATEWAY_INTERFACE"))	/* Not via CGI programs... */
    765   {
    766    /*
    767     * Verify that the current cupsUser() matches the current UID...
    768     */
    769 
    770     struct passwd	*pwd;		/* Password information */
    771     const char		*username;	/* Current username */
    772 
    773     username = cupsUser();
    774 
    775     if ((pwd = getpwnam(username)) != NULL && pwd->pw_uid == getuid())
    776     {
    777       httpSetAuthString(http, "PeerCred", username);
    778 
    779       DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
    780 		    http->authstring));
    781 
    782       return (0);
    783     }
    784   }
    785 #  endif /* SO_PEERCRED && AF_LOCAL */
    786 
    787  /*
    788   * Try opening a certificate file for this PID.  If that fails,
    789   * try the root certificate...
    790   */
    791 
    792   pid = getpid();
    793   snprintf(filename, sizeof(filename), "%s/certs/%d", cg->cups_statedir, pid);
    794   if ((fp = fopen(filename, "r")) == NULL && pid > 0)
    795   {
    796    /*
    797     * No certificate for this PID; see if we can get the root certificate...
    798     */
    799 
    800     DEBUG_printf(("9cups_local_auth: Unable to open file %s: %s",
    801                   filename, strerror(errno)));
    802 
    803 #  ifdef HAVE_GSSAPI
    804     if (!_cups_strncasecmp(http->fields[HTTP_FIELD_WWW_AUTHENTICATE], "Negotiate", 9))
    805     {
    806      /*
    807       * Kerberos required, don't try the root certificate...
    808       */
    809 
    810       return (1);
    811     }
    812 #  endif /* HAVE_GSSAPI */
    813 
    814 #  ifdef HAVE_AUTHORIZATION_H
    815     if (httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "authkey",
    816 		         auth_key, sizeof(auth_key)))
    817     {
    818      /*
    819       * Don't use the root certificate as a replacement for an authkey...
    820       */
    821 
    822       return (1);
    823     }
    824 #  endif /* HAVE_AUTHORIZATION_H */
    825     if (!httpGetSubField2(http, HTTP_FIELD_WWW_AUTHENTICATE, "trc", trc,
    826 	                  sizeof(trc)))
    827     {
    828      /*
    829       * Scheduler doesn't want us to use the root certificate...
    830       */
    831 
    832       return (1);
    833     }
    834 
    835     snprintf(filename, sizeof(filename), "%s/certs/0", cg->cups_statedir);
    836     fp = fopen(filename, "r");
    837   }
    838 
    839   if (fp)
    840   {
    841    /*
    842     * Read the certificate from the file...
    843     */
    844 
    845     char	certificate[33],	/* Certificate string */
    846 		*certptr;		/* Pointer to certificate string */
    847 
    848     certptr = fgets(certificate, sizeof(certificate), fp);
    849     fclose(fp);
    850 
    851     if (certptr)
    852     {
    853      /*
    854       * Set the authorization string and return...
    855       */
    856 
    857       httpSetAuthString(http, "Local", certificate);
    858 
    859       DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
    860 		    http->authstring));
    861 
    862       return (0);
    863     }
    864   }
    865 
    866   return (1);
    867 #endif /* WIN32 || __EMX__ */
    868 }
    869