2 * "$Id: auth.c 7720 2008-07-11 22:46:21Z mike $"
4 * Authentication functions for CUPS.
6 * Copyright 2007-2011 by Apple Inc.
7 * Copyright 1997-2007 by Easy Software Products.
9 * This file contains Kerberos support code, copyright 2006 by
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/".
18 * This file is subject to the Apple OS-Developed Software exception.
22 * cupsDoAuthentication() - Authenticate a request.
23 * cups_get_gssname() - Get GSSAPI name for authentication.
24 * cups_gss_printf() - Show error messages from GSSAPI...
25 * cups_local_auth() - Get the local authorization certificate if
26 * available/applicable...
30 * Include necessary headers...
33 #include "cups-private.h"
36 #if defined(WIN32) || defined(__EMX__)
40 #endif /* WIN32 || __EMX__ */
42 #if HAVE_AUTHORIZATION_H
43 # include <Security/Authorization.h>
44 # ifdef HAVE_SECBASEPRIV_H
45 # include <Security/SecBasePriv.h>
47 extern const char *cssmErrorString(int error
);
48 # endif /* HAVE_SECBASEPRIV_H */
49 #endif /* HAVE_AUTHORIZATION_H */
51 #if defined(SO_PEERCRED) && defined(AF_LOCAL)
53 #endif /* SO_PEERCRED && AF_LOCAL */
61 static gss_name_t
cups_get_gssname(http_t
*http
, const char *service_name
);
63 static void cups_gss_printf(OM_uint32 major_status
, OM_uint32 minor_status
,
66 # define cups_gss_printf(major, minor, message)
68 #endif /* HAVE_GSSAPI */
69 static int cups_local_auth(http_t
*http
);
73 * 'cupsDoAuthentication()' - Authenticate a request.
75 * This function should be called in response to a @code HTTP_UNAUTHORIZED@
76 * status, prior to resubmitting your request.
78 * @since CUPS 1.1.20/Mac OS X 10.4@
81 int /* O - 0 on success, -1 on error */
83 http_t
*http
, /* I - Connection to server or @code CUPS_HTTP_DEFAULT@ */
84 const char *method
, /* I - Request method ("GET", "POST", "PUT") */
85 const char *resource
) /* I - Resource path */
87 const char *password
; /* Password string */
88 char prompt
[1024], /* Prompt for user */
89 realm
[HTTP_MAX_VALUE
], /* realm="xyz" string */
90 nonce
[HTTP_MAX_VALUE
]; /* nonce="xyz" string */
91 int localauth
; /* Local authentication result */
92 _cups_globals_t
*cg
; /* Global data */
95 DEBUG_printf(("cupsDoAuthentication(http=%p, method=\"%s\", resource=\"%s\")",
96 http
, method
, resource
));
99 http
= _cupsConnect();
101 if (!http
|| !method
|| !resource
)
104 DEBUG_printf(("2cupsDoAuthentication: digest_tries=%d, userpass=\"%s\"",
105 http
->digest_tries
, http
->userpass
));
106 DEBUG_printf(("2cupsDoAuthentication: WWW-Authenticate=\"%s\"",
107 httpGetField(http
, HTTP_FIELD_WWW_AUTHENTICATE
)));
110 * Clear the current authentication string...
113 httpSetAuthString(http
, NULL
, NULL
);
116 * See if we can do local authentication...
119 if (http
->digest_tries
< 3)
121 if ((localauth
= cups_local_auth(http
)) == 0)
123 DEBUG_printf(("2cupsDoAuthentication: authstring=\"%s\"",
126 if (http
->status
== HTTP_UNAUTHORIZED
)
127 http
->digest_tries
++;
131 else if (localauth
== -1)
133 http
->status
= HTTP_AUTHORIZATION_CANCELED
;
134 return (-1); /* Error or canceled */
139 * Nope, see if we should retry the current username:password...
142 if ((http
->digest_tries
> 1 || !http
->userpass
[0]) &&
143 (!strncmp(http
->fields
[HTTP_FIELD_WWW_AUTHENTICATE
], "Basic", 5) ||
144 !strncmp(http
->fields
[HTTP_FIELD_WWW_AUTHENTICATE
], "Digest", 6)))
147 * Nope - get a new password from the user...
152 if (!cg
->lang_default
)
153 cg
->lang_default
= cupsLangDefault();
155 snprintf(prompt
, sizeof(prompt
),
156 _cupsLangString(cg
->lang_default
, _("Password for %s on %s? ")),
158 http
->hostname
[0] == '/' ? "localhost" : http
->hostname
);
160 http
->digest_tries
= strncasecmp(http
->fields
[HTTP_FIELD_WWW_AUTHENTICATE
],
162 http
->userpass
[0] = '\0';
164 if ((password
= cupsGetPassword2(prompt
, http
, method
, resource
)) == NULL
)
166 http
->status
= HTTP_AUTHORIZATION_CANCELED
;
170 snprintf(http
->userpass
, sizeof(http
->userpass
), "%s:%s", cupsUser(),
173 else if (http
->status
== HTTP_UNAUTHORIZED
)
174 http
->digest_tries
++;
176 if (http
->status
== HTTP_UNAUTHORIZED
&& http
->digest_tries
>= 3)
178 DEBUG_printf(("1cupsDoAuthentication: Too many authentication tries (%d)",
179 http
->digest_tries
));
181 http
->status
= HTTP_AUTHORIZATION_CANCELED
;
186 * Got a password; encode it for the server...
190 if (!strncmp(http
->fields
[HTTP_FIELD_WWW_AUTHENTICATE
], "Negotiate", 9))
193 * Kerberos authentication...
196 if (_cupsSetNegotiateAuthString(http
))
198 http
->status
= HTTP_AUTHORIZATION_CANCELED
;
203 #endif /* HAVE_GSSAPI */
204 if (!strncmp(http
->fields
[HTTP_FIELD_WWW_AUTHENTICATE
], "Basic", 5))
207 * Basic authentication...
210 char encode
[256]; /* Base64 buffer */
213 httpEncode64_2(encode
, sizeof(encode
), http
->userpass
,
214 (int)strlen(http
->userpass
));
215 httpSetAuthString(http
, "Basic", encode
);
217 else if (!strncmp(http
->fields
[HTTP_FIELD_WWW_AUTHENTICATE
], "Digest", 6))
220 * Digest authentication...
223 char encode
[33], /* MD5 buffer */
224 digest
[1024]; /* Digest auth data */
227 httpGetSubField(http
, HTTP_FIELD_WWW_AUTHENTICATE
, "realm", realm
);
228 httpGetSubField(http
, HTTP_FIELD_WWW_AUTHENTICATE
, "nonce", nonce
);
230 httpMD5(cupsUser(), realm
, strchr(http
->userpass
, ':') + 1, encode
);
231 httpMD5Final(nonce
, method
, resource
, encode
);
232 snprintf(digest
, sizeof(digest
),
233 "username=\"%s\", realm=\"%s\", nonce=\"%s\", uri=\"%s\", "
234 "response=\"%s\"", cupsUser(), realm
, nonce
, resource
, encode
);
235 httpSetAuthString(http
, "Digest", digest
);
239 DEBUG_printf(("1cupsDoAuthentication: Unknown auth type: \"%s\"",
240 http
->fields
[HTTP_FIELD_WWW_AUTHENTICATE
]));
241 http
->status
= HTTP_AUTHORIZATION_CANCELED
;
245 DEBUG_printf(("1cupsDoAuthentication: authstring=\"%s\"", http
->authstring
));
253 * '_cupsSetNegotiateAuthString()' - Set the Kerberos authentication string.
256 int /* O - 0 on success, -1 on error */
257 _cupsSetNegotiateAuthString(
258 http_t
*http
) /* I - Connection to server */
260 OM_uint32 minor_status
, /* Minor status code */
261 major_status
; /* Major status code */
262 gss_buffer_desc output_token
= GSS_C_EMPTY_BUFFER
;
264 char *gss_service_name
; /* GSS service name */
269 * If the weak-linked GSSAPI/Kerberos library is not present, don't try
273 if (gss_init_sec_context
== NULL
)
275 DEBUG_puts("1_cupsSetNegotiateAuthString: Weak-linked GSSAPI/Kerberos "
276 "framework is not present");
279 # endif /* __APPLE__ */
281 if (http
->gssname
== GSS_C_NO_NAME
)
283 if ((gss_service_name
= getenv("CUPS_GSSSERVICENAME")) == NULL
)
284 gss_service_name
= CUPS_DEFAULT_GSSSERVICENAME
;
286 DEBUG_puts("2_cupsSetNegotiateAuthString: GSS service name set via "
287 "environment variable");
289 http
->gssname
= cups_get_gssname(http
, gss_service_name
);
292 if (http
->gssctx
!= GSS_C_NO_CONTEXT
)
294 gss_delete_sec_context(&minor_status
, &http
->gssctx
, GSS_C_NO_BUFFER
);
295 http
->gssctx
= GSS_C_NO_CONTEXT
;
298 major_status
= gss_init_sec_context(&minor_status
, GSS_C_NO_CREDENTIAL
,
300 http
->gssname
, http
->gssmech
,
301 #ifdef GSS_C_DELEG_POLICY_FLAG
302 GSS_C_DELEG_POLICY_FLAG
|
303 #endif /* GSS_C_DELEG_POLICY_FLAG */
304 GSS_C_MUTUAL_FLAG
| GSS_C_INTEG_FLAG
,
306 GSS_C_NO_CHANNEL_BINDINGS
,
307 GSS_C_NO_BUFFER
, &http
->gssmech
,
308 &output_token
, NULL
, NULL
);
310 if (GSS_ERROR(major_status
))
312 cups_gss_printf(major_status
, minor_status
,
313 "_cupsSetNegotiateAuthString: Unable to initialize "
318 if (major_status
== GSS_S_CONTINUE_NEEDED
)
319 cups_gss_printf(major_status
, minor_status
,
320 "_cupsSetNegotiateAuthString: Continuation needed!");
322 if (output_token
.length
> 0 && output_token
.length
<= 65536)
325 * Allocate the authorization string since Windows KDCs can have
326 * arbitrarily large credentials...
329 int authsize
= 10 + /* "Negotiate " */
330 output_token
.length
* 4 / 3 + 1 + /* Base64 */
333 httpSetAuthString(http
, NULL
, NULL
);
335 if ((http
->authstring
= malloc(authsize
)) == NULL
)
337 http
->authstring
= http
->_authstring
;
338 authsize
= sizeof(http
->_authstring
);
341 strcpy(http
->authstring
, "Negotiate ");
342 httpEncode64_2(http
->authstring
+ 10, authsize
- 10, output_token
.value
,
343 output_token
.length
);
345 gss_release_buffer(&minor_status
, &output_token
);
349 DEBUG_printf(("1_cupsSetNegotiateAuthString: Kerberos credentials too "
350 "large - %d bytes!", (int)output_token
.length
));
351 gss_release_buffer(&minor_status
, &output_token
);
361 * 'cups_get_gssname()' - Get CUPS service credentials for authentication.
364 static gss_name_t
/* O - Server name */
366 http_t
*http
, /* I - Connection to server */
367 const char *service_name
) /* I - Service name */
369 gss_buffer_desc token
= GSS_C_EMPTY_BUFFER
;
371 OM_uint32 major_status
, /* Major status code */
372 minor_status
; /* Minor status code */
373 gss_name_t server_name
; /* Server name */
374 char buf
[1024], /* Name buffer */
375 fqdn
[HTTP_MAX_URI
]; /* Server name buffer */
378 DEBUG_printf(("7cups_get_gssname(http=%p, service_name=\"%s\")", http
,
383 * Get the hostname...
386 httpGetHostname(http
, fqdn
, sizeof(fqdn
));
388 if (!strcmp(fqdn
, "localhost"))
389 httpGetHostname(NULL
, fqdn
, sizeof(fqdn
));
392 * Get a server name we can use for authentication purposes...
395 snprintf(buf
, sizeof(buf
), "%s@%s", service_name
, fqdn
);
397 DEBUG_printf(("9cups_get_gssname: Looking up %s...", buf
));
400 token
.length
= strlen(buf
);
401 server_name
= GSS_C_NO_NAME
;
402 major_status
= gss_import_name(&minor_status
, &token
,
403 GSS_C_NT_HOSTBASED_SERVICE
,
406 if (GSS_ERROR(major_status
))
408 cups_gss_printf(major_status
, minor_status
,
409 "cups_get_gssname: gss_import_name() failed");
413 return (server_name
);
419 * 'cups_gss_printf()' - Show debug error messages from GSSAPI...
423 cups_gss_printf(OM_uint32 major_status
,/* I - Major status code */
424 OM_uint32 minor_status
,/* I - Minor status code */
425 const char *message
) /* I - Prefix for error message */
427 OM_uint32 err_major_status
, /* Major status code for display */
428 err_minor_status
; /* Minor status code for display */
429 OM_uint32 msg_ctx
; /* Message context */
430 gss_buffer_desc major_status_string
= GSS_C_EMPTY_BUFFER
,
431 /* Major status message */
432 minor_status_string
= GSS_C_EMPTY_BUFFER
;
433 /* Minor status message */
437 err_major_status
= gss_display_status(&err_minor_status
,
442 &major_status_string
);
444 if (!GSS_ERROR(err_major_status
))
445 gss_display_status(&err_minor_status
, minor_status
, GSS_C_MECH_CODE
,
446 GSS_C_NULL_OID
, &msg_ctx
, &minor_status_string
);
448 DEBUG_printf(("1%s: %s, %s", message
, (char *)major_status_string
.value
,
449 (char *)minor_status_string
.value
));
451 gss_release_buffer(&err_minor_status
, &major_status_string
);
452 gss_release_buffer(&err_minor_status
, &minor_status_string
);
455 #endif /* HAVE_GSSAPI */
459 * 'cups_local_auth()' - Get the local authorization certificate if
460 * available/applicable...
463 static int /* O - 0 if available */
464 /* 1 if not available */
466 cups_local_auth(http_t
*http
) /* I - HTTP connection to server */
468 #if defined(WIN32) || defined(__EMX__)
470 * Currently WIN32 and OS-2 do not support the CUPS server...
475 int pid
; /* Current process ID */
476 FILE *fp
; /* Certificate file */
477 char trc
[16], /* Try Root Certificate parameter */
478 filename
[1024], /* Certificate filename */
479 certificate
[33];/* Certificate string */
480 _cups_globals_t
*cg
= _cupsGlobals(); /* Global data */
481 # if defined(HAVE_AUTHORIZATION_H)
482 OSStatus status
; /* Status */
483 AuthorizationItem auth_right
; /* Authorization right */
484 AuthorizationRights auth_rights
; /* Authorization rights */
485 AuthorizationFlags auth_flags
; /* Authorization flags */
486 AuthorizationExternalForm auth_extrn
; /* Authorization ref external */
487 char auth_key
[1024]; /* Buffer */
488 char buffer
[1024]; /* Buffer */
489 # endif /* HAVE_AUTHORIZATION_H */
492 DEBUG_printf(("7cups_local_auth(http=%p) hostaddr=%s, hostname=\"%s\"",
493 http
, httpAddrString(http
->hostaddr
, filename
, sizeof(filename
)), http
->hostname
));
496 * See if we are accessing localhost...
499 if (!httpAddrLocalhost(http
->hostaddr
) &&
500 strcasecmp(http
->hostname
, "localhost") != 0)
502 DEBUG_puts("8cups_local_auth: Not a local connection!");
506 # if defined(HAVE_AUTHORIZATION_H)
508 * Delete any previous authorization reference...
513 AuthorizationFree(http
->auth_ref
, kAuthorizationFlagDefaults
);
514 http
->auth_ref
= NULL
;
517 if (!getenv("GATEWAY_INTERFACE") &&
518 httpGetSubField2(http
, HTTP_FIELD_WWW_AUTHENTICATE
, "authkey",
519 auth_key
, sizeof(auth_key
)))
521 status
= AuthorizationCreate(NULL
, kAuthorizationEmptyEnvironment
,
522 kAuthorizationFlagDefaults
, &http
->auth_ref
);
523 if (status
!= errAuthorizationSuccess
)
525 DEBUG_printf(("8cups_local_auth: AuthorizationCreate() returned %d (%s)",
526 (int)status
, cssmErrorString(status
)));
530 auth_right
.name
= auth_key
;
531 auth_right
.valueLength
= 0;
532 auth_right
.value
= NULL
;
533 auth_right
.flags
= 0;
535 auth_rights
.count
= 1;
536 auth_rights
.items
= &auth_right
;
538 auth_flags
= kAuthorizationFlagDefaults
|
539 kAuthorizationFlagPreAuthorize
|
540 kAuthorizationFlagInteractionAllowed
|
541 kAuthorizationFlagExtendRights
;
543 status
= AuthorizationCopyRights(http
->auth_ref
, &auth_rights
,
544 kAuthorizationEmptyEnvironment
,
546 if (status
== errAuthorizationSuccess
)
547 status
= AuthorizationMakeExternalForm(http
->auth_ref
, &auth_extrn
);
549 if (status
== errAuthorizationSuccess
)
552 * Set the authorization string and return...
555 httpEncode64_2(buffer
, sizeof(buffer
), (void *)&auth_extrn
,
558 httpSetAuthString(http
, "AuthRef", buffer
);
560 DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
564 else if (status
== errAuthorizationCanceled
)
567 DEBUG_printf(("9cups_local_auth: AuthorizationCopyRights() returned %d (%s)",
568 (int)status
, cssmErrorString(status
)));
571 * Fall through to try certificates...
574 # endif /* HAVE_AUTHORIZATION_H */
576 # if defined(SO_PEERCRED) && defined(AF_LOCAL)
578 * See if we can authenticate using the peer credentials provided over a
579 * domain socket; if so, specify "PeerCred username" as the authentication
585 strncmp(http
->fields
[HTTP_FIELD_WWW_AUTHENTICATE
], "Negotiate", 9) &&
586 # endif /* HAVE_GSSAPI */
587 # ifdef HAVE_AUTHORIZATION_H
588 !httpGetSubField2(http
, HTTP_FIELD_WWW_AUTHENTICATE
, "authkey",
589 auth_key
, sizeof(auth_key
)) &&
590 # endif /* HAVE_AUTHORIZATION_H */
591 http
->hostaddr
->addr
.sa_family
== AF_LOCAL
&&
592 !getenv("GATEWAY_INTERFACE")) /* Not via CGI programs... */
595 * Verify that the current cupsUser() matches the current UID...
598 struct passwd
*pwd
; /* Password information */
599 const char *username
; /* Current username */
601 username
= cupsUser();
603 if ((pwd
= getpwnam(username
)) != NULL
&& pwd
->pw_uid
== getuid())
605 httpSetAuthString(http
, "PeerCred", username
);
607 DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
613 # endif /* SO_PEERCRED && AF_LOCAL */
616 * Try opening a certificate file for this PID. If that fails,
617 * try the root certificate...
621 snprintf(filename
, sizeof(filename
), "%s/certs/%d", cg
->cups_statedir
, pid
);
622 if ((fp
= fopen(filename
, "r")) == NULL
&& pid
> 0)
625 * No certificate for this PID; see if we can get the root certificate...
628 DEBUG_printf(("9cups_local_auth: Unable to open file %s: %s",
629 filename
, strerror(errno
)));
632 if (!strncmp(http
->fields
[HTTP_FIELD_WWW_AUTHENTICATE
], "Negotiate", 9))
635 * Kerberos required, don't try the root certificate...
640 #endif /* HAVE_GSSAPI */
642 if (!httpGetSubField2(http
, HTTP_FIELD_WWW_AUTHENTICATE
, "trc", trc
,
646 * Scheduler doesn't want us to use the root certificate...
652 snprintf(filename
, sizeof(filename
), "%s/certs/0", cg
->cups_statedir
);
653 fp
= fopen(filename
, "r");
659 * Read the certificate from the file...
662 fgets(certificate
, sizeof(certificate
), fp
);
666 * Set the authorization string and return...
669 httpSetAuthString(http
, "Local", certificate
);
671 DEBUG_printf(("8cups_local_auth: Returning authstring=\"%s\"",
678 #endif /* WIN32 || __EMX__ */
683 * End of "$Id: auth.c 7720 2008-07-11 22:46:21Z mike $".