From 3cb6652e6fb85f3d5eb5b82e752b2ffbb8ef93ce Mon Sep 17 00:00:00 2001
From: Zdenek Dohnal <zdohnal@redhat.com>
Date: Mon, 3 Oct 2022 10:14:09 +0200
Subject: [PATCH] 2066528 - use 'localhost' if the mDNS record shows your local
 hostname

---
 cups-resolve-local.patch | 97 ++++++++++++++++++++++++++++++++++++++++
 cups.spec                |  7 ++-
 2 files changed, 103 insertions(+), 1 deletion(-)
 create mode 100644 cups-resolve-local.patch

diff --git a/cups-resolve-local.patch b/cups-resolve-local.patch
new file mode 100644
index 0000000..bc6c96a
--- /dev/null
+++ b/cups-resolve-local.patch
@@ -0,0 +1,97 @@
+diff --git a/scheduler/ipp.c b/scheduler/ipp.c
+index 9984b79..dd85173 100644
+--- a/scheduler/ipp.c
++++ b/scheduler/ipp.c
+@@ -5898,6 +5898,11 @@ create_local_printer(
+ 		*nameptr,		/* Pointer into name */
+ 		uri[1024];		/* printer-uri-supported value */
+   const char	*ptr;			/* Pointer into attribute value */
++  char		scheme[HTTP_MAX_URI],	/* Scheme portion of URI */
++		userpass[HTTP_MAX_URI],	/* Username portion of URI */
++		host[HTTP_MAX_URI],	/* Host portion of URI */
++		resource[HTTP_MAX_URI];	/* Resource portion of URI */
++  int		port;			/* Port portion of URI */
+ 
+ 
+  /*
+@@ -5961,6 +5966,13 @@ create_local_printer(
+ 
+     return;
+   }
++  ptr = ippGetString(device_uri, 0, NULL);
++  if (!ptr || !ptr[0])
++  {
++    send_ipp_status(con, IPP_STATUS_ERROR_BAD_REQUEST, _("Attribute \"%s\" has empty value."), "device-uri");
++
++    return;
++  }
+ 
+   printer_geo_location = ippFindAttribute(con->request, "printer-geo-location", IPP_TAG_URI);
+   printer_info         = ippFindAttribute(con->request, "printer-info", IPP_TAG_TEXT);
+@@ -5989,7 +6001,65 @@ create_local_printer(
+   printer->shared    = 0;
+   printer->temporary = 1;
+ 
+-  cupsdSetDeviceURI(printer, ippGetString(device_uri, 0, NULL));
++ /*
++  * Check device URI if it has the same hostname as we have, if so, replace
++  * the hostname by localhost. This way we assure that local-only services
++  * like ipp-usb or Printer Applications always work.
++  *
++  * When comparing our hostname with the one in the device URI,
++  * consider names with or without trailing dot ('.') the same. Also
++  * compare case-insensitively.
++  */
++
++#ifdef HAVE_DNSSD
++  if (DNSSDHostName)
++    nameptr = DNSSDHostName;
++  else
++#endif
++  if (ServerName)
++    nameptr = ServerName;
++  else
++    nameptr = NULL;
++
++  if (nameptr)
++  {
++    int host_len,
++        server_name_len;
++
++    /* Get host name of device URI */
++    httpSeparateURI(HTTP_URI_CODING_ALL, ptr,
++		    scheme, sizeof(scheme), userpass, sizeof(userpass), host,
++		    sizeof(host), &port, resource, sizeof(resource));
++
++    /* Take trailing dot out of comparison */
++    host_len = strlen(host);
++    if (host_len > 1 && host[host_len - 1] == '.')
++      host_len --;
++
++    server_name_len = strlen(nameptr);
++    if (server_name_len > 1 && nameptr[server_name_len - 1] == '.')
++      server_name_len --;
++
++   /*
++    * If we have no DNSSDHostName but only a ServerName (if we are not
++    * sharing printers, Browsing = Off) the ServerName has no ".local"
++    * but the requested device URI has. Take this into account.
++    */
++
++    if (nameptr == ServerName && host_len >= 6 && (server_name_len < 6 || strcmp(nameptr + server_name_len - 6, ".local") != 0) && strcmp(host + host_len - 6, ".local") == 0)
++      host_len -= 6;
++
++    if (host_len == server_name_len && strncasecmp(host, nameptr, host_len) == 0)
++      ptr = "localhost";
++    else
++      ptr = host;
++
++    httpAssembleURI(HTTP_URI_CODING_ALL, uri, sizeof(uri), scheme, userpass,
++		    ptr, port, resource);
++    cupsdSetDeviceURI(printer, uri);
++  }
++  else
++    cupsdSetDeviceURI(printer, ptr);
+ 
+   if (printer_geo_location)
+     cupsdSetString(&printer->geo_location, ippGetString(printer_geo_location, 0, NULL));
diff --git a/cups.spec b/cups.spec
index 491e4f9..5651221 100644
--- a/cups.spec
+++ b/cups.spec
@@ -15,7 +15,7 @@ Summary: CUPS printing system
 Name: cups
 Epoch: 1
 Version: 2.4.2
-Release: 4%{?dist}
+Release: 5%{?dist}
 License: ASL 2.0
 Url: https://openprinting.github.io/cups/
 # Apple stopped uploading the new versions into github, use OpenPrinting fork
@@ -68,6 +68,7 @@ Patch100: cups-lspp.patch
 
 #### UPSTREAM PATCHES (starts with 1000) ####
 Patch1001: 0001-scheduler-ipp.c-Allocate-device_uri-via-cupsdSetStri.patch
+Patch1002: cups-resolve-local.patch
 
 ##### Patches removed because IMHO they aren't no longer needed
 ##### but still I'll leave them in git in case their removal
@@ -272,6 +273,7 @@ to CUPS daemon. This solution will substitute printer drivers and raw queues in
 
 # UPSTREAM PATCHES
 %patch1001 -p1 -b .invalid-pointer-uri
+%patch1002 -p1 -b .localhost
 
 
 %if %{lspp}
@@ -664,6 +666,9 @@ rm -f %{cups_serverbin}/backend/smb
 %{_mandir}/man7/ippeveps.7.gz
 
 %changelog
+* Mon Oct 03 2022 Zdenek Dohnal <zdohnal@redhat.com> - 1:2.4.2-5
+- 2066528 - use 'localhost' if the mDNS record shows your local hostname
+
 * Thu Aug 11 2022 Zdenek Dohnal <zdohnal@redhat.com> - 1:2.4.2-4
 - 2115002 - Reenable kerberos/gssapi support