File fix-negotiate-authentication-between-CGIs-and-s... of Package cups

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File fix-negotiate-authentication-between-CGIs-and-scheduler.patch of Package cups (Revision 83f8ae122e6503e0120f9ab72453317c)

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From d4521ed0df7e625ccf2bc079bab6f48c46ef9bf9 Mon Sep 17 00:00:00 2001
From: Samuel Cabrero <scabrero@suse.de>
Date: Mon, 26 Oct 2020 17:35:22 +0100
Subject: [PATCH 1/4] Avoid infinite loop in admin.cgi when negotiate is used

SetAuthorizationString with NULL argument sets an empty string.

Related: #5596

Signed-off-by: Samuel Cabrero <scabrero@suse.de>
---
 cups/auth.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cups/auth.c b/cups/auth.c
index db45bbba6..f2409350a 100644
--- a/cups/auth.c
+++ b/cups/auth.c
@@ -295,7 +295,7 @@ cupsDoAuthentication(
     }
   }
 
-  if (http->authstring)
+  if (http->authstring && http->authstring[0])
   {
     DEBUG_printf(("1cupsDoAuthentication: authstring=\"%s\".", http->authstring));
 
-- 
2.30.2

From 61ad7780bc7d0593e3225d088ac6dff31badf801 Mon Sep 17 00:00:00 2001
From: Samuel Cabrero <scabrero@suse.de>
Date: Tue, 27 Oct 2020 16:11:41 +0100
Subject: [PATCH 2/4] Add cups_is_local_connection() to check if connection is
 to localhost

Related: #5596

Signed-off-by: Samuel Cabrero <scabrero@suse.de>
---
 cups/auth.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/cups/auth.c b/cups/auth.c
index f2409350a..d2956438d 100644
--- a/cups/auth.c
+++ b/cups/auth.c
@@ -90,6 +90,7 @@ static void	cups_gss_printf(OM_uint32 major_status, OM_uint32 minor_status,
 #    define	cups_gss_printf(major, minor, message)
 #  endif /* DEBUG */
 #endif /* HAVE_GSSAPI */
+static int	cups_is_local_connection(http_t *http);
 static int	cups_local_auth(http_t *http);
 
 
@@ -916,6 +917,14 @@ cups_gss_printf(OM_uint32  major_status,/* I - Major status code */
 #  endif /* DEBUG */
 #endif /* HAVE_GSSAPI */
 
+static int				/* O - 0 if not a local connection */
+					/*     1  if local connection */
+cups_is_local_connection(http_t *http)	/* I - HTTP connection to server */
+{
+  if (!httpAddrLocalhost(http->hostaddr) && _cups_strcasecmp(http->hostname, "localhost") != 0)
+    return 0;
+  return 1;
+}
 
 /*
  * 'cups_local_auth()' - Get the local authorization certificate if
@@ -958,7 +967,7 @@ cups_local_auth(http_t *http)		/* I - HTTP connection to server */
   * See if we are accessing localhost...
   */
 
-  if (!httpAddrLocalhost(http->hostaddr) && _cups_strcasecmp(http->hostname, "localhost") != 0)
+  if (!cups_is_local_connection(http))
   {
     DEBUG_puts("8cups_local_auth: Not a local connection!");
     return (1);
-- 
2.30.2

From f629d079750a86b1b605c285f99c0dea3933ca50 Mon Sep 17 00:00:00 2001
From: Samuel Cabrero <scabrero@suse.de>
Date: Tue, 27 Oct 2020 16:23:30 +0100
Subject: [PATCH 3/4] Try local kerberos ccache credentials only for remote
 servers

If connecting to localhost then proceed to ask the client for the
authorization using cupsGetPassword2. The get password callback will
return 401 to the client with WWW-Authenticate: Negotiate.

Fixes: #5596

Signed-off-by: Samuel Cabrero <scabrero@suse.de>
---
 cups/auth.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/cups/auth.c b/cups/auth.c
index d2956438d..9661657fc 100644
--- a/cups/auth.c
+++ b/cups/auth.c
@@ -175,10 +175,10 @@ cupsDoAuthentication(
     DEBUG_printf(("2cupsDoAuthentication: Trying scheme \"%s\"...", scheme));
 
 #ifdef HAVE_GSSAPI
-    if (!_cups_strcasecmp(scheme, "Negotiate"))
+    if (!_cups_strcasecmp(scheme, "Negotiate") && !cups_is_local_connection(http))
     {
      /*
-      * Kerberos authentication...
+      * Kerberos authentication to remote server...
       */
 
       int gss_status;			/* Auth status */
@@ -202,7 +202,9 @@ cupsDoAuthentication(
     }
     else
 #endif /* HAVE_GSSAPI */
-    if (_cups_strcasecmp(scheme, "Basic") && _cups_strcasecmp(scheme, "Digest"))
+    if (_cups_strcasecmp(scheme, "Basic") &&
+	_cups_strcasecmp(scheme, "Digest") &&
+	_cups_strcasecmp(scheme, "Negotiate"))
     {
      /*
       * Other schemes not yet supported...
@@ -216,7 +218,7 @@ cupsDoAuthentication(
     * See if we should retry the current username:password...
     */
 
-    if ((http->digest_tries > 1 || !http->userpass[0]) && (!_cups_strcasecmp(scheme, "Basic") || (!_cups_strcasecmp(scheme, "Digest"))))
+    if (http->digest_tries > 1 || !http->userpass[0])
     {
      /*
       * Nope - get a new password from the user...
-- 
2.30.2

From 0563a28b18b21d5574a5e0e38b74246146074bbf Mon Sep 17 00:00:00 2001
From: Samuel Cabrero <scabrero@suse.de>
Date: Tue, 27 Oct 2020 16:18:03 +0100
Subject: [PATCH 4/4] Allow Local authentication for Negotiate

PeerCred is also possible if address family is AF_LOCAL. This will allow
the CGI programs to generate the authorization from the local
certificates based on PID also when Negotiate is used for local
connections:

Client                       CGI
Browser <- Remote conn -> admin.cgi <--- Localhost conn --->  Scheduler
  |                           |                                    |
  + --- HTTP/POST /admin/ --> |                                    |
  |                           + --- CUPS-Get-Devices ------------> |
  |                           |                                    |
  |                           | <-- 401 Unauthorized --------------+
  |                           |     WWW-Authenticate:              |
  |                           |       Negotiate, (PeerCred,) Local |
  |                           |                                    |
  | <-- 401 Unauthorized -----+                                    |
  |     WWW-Authenticate:     |                                    |
  |       Negotiate           |                                    |
  |                           |                                    |
  | --- HTTP/POST /admin/ --> |                                    |
  |     Authorization:        + --- IPP CUPS-GetDevices ---------> |
  |       Negotiate           |     Authorization: Local <cert>    |
  |                           |                                    |

Fixes: #5596

Signed-off-by: Samuel Cabrero <scabrero@suse.de>
---
 cups/auth.c        | 5 -----
 scheduler/client.c | 9 ++-------
 2 files changed, 2 insertions(+), 12 deletions(-)

diff --git a/cups/auth.c b/cups/auth.c
index 9661657fc..b6fec6b98 100644
--- a/cups/auth.c
+++ b/cups/auth.c
@@ -1043,11 +1043,6 @@ cups_local_auth(http_t *http)		/* I - HTTP connection to server */
   }
 #  endif /* HAVE_AUTHORIZATION_H */
 
-#  ifdef HAVE_GSSAPI
-  if (cups_auth_find(www_auth, "Negotiate"))
-    return (1);
-#  endif /* HAVE_GSSAPI */
-
 #  if defined(SO_PEERCRED) && defined(AF_LOCAL)
  /*
   * See if we can authenticate using the peer credentials provided over a
diff --git a/scheduler/client.c b/scheduler/client.c
index c2ee8f12a..56797d58d 100644
--- a/scheduler/client.c
+++ b/scheduler/client.c
@@ -2109,18 +2109,13 @@ cupsdSendHeader(
     }
     else if (auth_type == CUPSD_AUTH_NEGOTIATE)
     {
-#if defined(SO_PEERCRED) && defined(AF_LOCAL)
-      if (httpAddrFamily(httpGetAddress(con->http)) == AF_LOCAL)
-	strlcpy(auth_str, "PeerCred", sizeof(auth_str));
-      else
-#endif /* SO_PEERCRED && AF_LOCAL */
       strlcpy(auth_str, "Negotiate", sizeof(auth_str));
     }
 
-    if (con->best && auth_type != CUPSD_AUTH_NEGOTIATE && !con->is_browser && !_cups_strcasecmp(httpGetHostname(con->http, NULL, 0), "localhost"))
+    if (con->best && !con->is_browser && !_cups_strcasecmp(httpGetHostname(con->http, NULL, 0), "localhost"))
     {
      /*
-      * Add a "trc" (try root certification) parameter for local non-Kerberos
+      * Add a "trc" (try root certification) parameter for local
       * requests when the request requires system group membership - then the
       * client knows the root certificate can/should be used.
       *
-- 
2.30.2

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File fix-negotiate-authentication-between-CGIs-and-scheduler.patch of Package cups (Revision 83f8ae122e6503e0120f9ab72453317c)

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