Hi,

I did more testes regarding this issue, suspecting a wrong configuration, but I just confirmed the issue.

Server has in cupsd.conf:

  Port 63101
  BrowsePort 63101

Client has cupsd.conf:

  BrowsePoll 192.168.122.99:63101
  BrowsePort 63101


Firewall allows traffic:

7    ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0           state NEW tcp dpt:63101 
8    ACCEPT     udp  --  0.0.0.0/0            0.0.0.0/0           state NEW udp dpt:63101 

SELinux allows the non-standaard port 63101 in the server and the client:

# semanage port -l | grep ipp
ipp_port_t                     tcp      63101, 631, 8610-8614
ipp_port_t                     udp      63101, 631, 8610-8614


All the non-Gtk application work as expected, using only the port 63101/tcp and udp, but when the Gtk Print Dialog starts the following communications is attempted and fails:

20:24:33.886932 IP 192.168.122.228.52755 > 192.168.122.99.631: Flags [S], seq 1291153458, win 14600, options [mss 1460,sackOK,TS val 5593038 ecr 0,nop,wscale 7], length 0
20:24:33.887248 IP 192.168.122.99.631 > 192.168.122.228.52755: Flags [R.], seq 0, ack 1291153459, win 0, length 0

I tried setting the IPP_PORT Env variable without success.

Looking at the source code, I noticed that the Gtk platform when connecting to the cups server uses always the Cups API function "ippPort()" :

      request->http = httpConnectEncrypt (request->server, 
                                          ippPort (), 
                                          cupsEncryption ());



Looking at the ippPort definition in gtk+-2.18.9/modules/printbackends/cups/gtkcupsutils.c :


######################
int                                     /* O - Port number */
ippPort(void)
{
  _cups_globals_t *cg = _cupsGlobals(); /* Pointer to library globals */


  DEBUG_puts("ippPort()");

  if (!cg->ipp_port)
    _cupsSetDefaults();

  DEBUG_printf(("1ippPort: Returning %d...", cg->ipp_port));

  return (cg->ipp_port);
}
#######################


It's not clear what port the function is really returning, but it must be in the library globals:



Any thoughts ?

Thank you

Best regards,
Rui Gouveia
Red Hat UK, GSS

Hello again,

The function _cupsSetDefaults in cups-1.4.2/cups/usersys.c is:

#######################
/*
* '_cupsSetDefaults()' - Set the default server, port, and encryption.
 */

void
_cupsSetDefaults(void)
{
  cups_file_t   *fp;                    /* File */
  const char    *home,                  /* Home directory of user */
                *cups_encryption,       /* CUPS_ENCRYPTION env var */
                *cups_server;           /* CUPS_SERVER env var */
  char          filename[1024];         /* Filename */
  _cups_globals_t *cg = _cupsGlobals(); /* Pointer to library globals */


  DEBUG_puts("_cupsSetDefaults()");

 /*
* First collect environment variables...
  */

  cups_encryption = getenv("CUPS_ENCRYPTION");
  cups_server     = getenv("CUPS_SERVER");

 /*
* Then, if needed, the .cups/client.conf or .cupsrc file in the home
* directory...
  */

  if ((cg->encryption == (http_encryption_t)-1 || !cg->server[0] ||
       !cg->ipp_port) && (home = getenv("HOME")) != NULL)
  {
   /*
	* Look for ~/.cups/client.conf or ~/.cupsrc...
    */

    snprintf(filename, sizeof(filename), "%s/.cups/client.conf", home);
    if ((fp = cupsFileOpen(filename, "r")) == NULL)
    {
      snprintf(filename, sizeof(filename), "%s/.cupsrc", home);
      fp = cupsFileOpen(filename, "r");
    }

    if (fp)
    {
      cups_read_client_conf(fp, cg, cups_encryption, cups_server);
      cupsFileClose(fp);
    }
  }

  if (cg->encryption == (http_encryption_t)-1 || !cg->server[0] ||
      !cg->ipp_port)
  {
   /*
	* Look for CUPS_SERVERROOT/client.conf...
    */

    snprintf(filename, sizeof(filename), "%s/client.conf", cg->cups_serverroot);
    if ((fp = cupsFileOpen(filename, "r")) != NULL)
    {
      cups_read_client_conf(fp, cg, cups_encryption, cups_server);
      cupsFileClose(fp);
    }
  }

 /*
* If we still have things that aren't set, use the compiled in defaults...
  */

  if (cg->encryption == (http_encryption_t)-1)
    cg->encryption = HTTP_ENCRYPT_IF_REQUESTED;

  if (!cg->server[0])
  {
    if (!cups_server)
    {
#ifdef CUPS_DEFAULT_DOMAINSOCKET
     /*
	* If we are compiled with domain socket support, only use the
	* domain socket if it exists and has the right permissions...
      */

      struct stat       sockinfo;       /* Domain socket information */

      if (!stat(CUPS_DEFAULT_DOMAINSOCKET, &sockinfo) &&
          (sockinfo.st_mode & S_IRWXO) == S_IRWXO)
        cups_server = CUPS_DEFAULT_DOMAINSOCKET;
      else
#endif /* CUPS_DEFAULT_DOMAINSOCKET */
      cups_server = "localhost";
    }

    cupsSetServer(cups_server);
  }

  if (!cg->ipp_port)
  {
    const char          *ipp_port;      /* IPP_PORT environment variable */
    struct servent      *service;       /* Port number info */  


    if ((ipp_port = getenv("IPP_PORT")) != NULL)
    {
      if ((cg->ipp_port = atoi(ipp_port)) <= 0)
        cg->ipp_port = CUPS_DEFAULT_IPP_PORT;
    }
    else if ((service = getservbyname("ipp", NULL)) == NULL ||
             service->s_port <= 0)
      cg->ipp_port = CUPS_DEFAULT_IPP_PORT;
    else
      cg->ipp_port = ntohs(service->s_port);
  }
}
#######################


If I define the ENV vars: IPP_PORT and CUPS_SERVER it works!!! :)

Since the server is parsed correctly, the problem must be in the port selection. Agree?

Thank you

Best regards,
Rui Gouveia
Red Hat UK, GSS

Looking at the function _cupsSetDefaults(void)...

Since the server is parsed correctly, the problem must be in the port
selection. Correct me if I'm wrong.

### If cg->ipp_port is not defined

  if (!cg->ipp_port)
  {
    const char          *ipp_port;      /* IPP_PORT environment variable */
    struct servent      *service;       /* Port number info */  

### ipp_port takes the value from ENV(IPP_PORT) and is not null.

    if ((ipp_port = getenv("IPP_PORT")) != NULL)
    {

### If conversion from string to integer generates an
### error cg->ipp_port takes the default value CUPS_DEFAULT_IPP_PORT

      if ((cg->ipp_port = atoi(ipp_port)) <= 0)
        cg->ipp_port = CUPS_DEFAULT_IPP_PORT;
    }

### else, if ipp does not exists in the system services
### or service->s_port has an invalid value, then
### cg->ipp_port takes the default value CUPS_DEFAULT_IPP_PORT

    else if ((service = getservbyname("ipp", NULL)) == NULL ||
             service->s_port <= 0)
      cg->ipp_port = CUPS_DEFAULT_IPP_PORT;

### else, cg->ipp_port takes the value of the services value.

    else
      cg->ipp_port = ntohs(service->s_port);
  }


So, if IPP_PORT is defined, all is ok, but if not, this code jumps directly to getting the default value in services.

So, where is the value in the configuration read ? I may be analyzing the wrong code here...

Help is appreciated.


Thank you

Best regards,
Rui Gouveia
Red Hat UK, GSS

Created attachment 280493 [details] [review]
Check connection to remote CUPS server on correct port (gtk+-2.24 version)

The problem is that the connection test connects always to standard port provided by ippPort(). It should connect to the port taken from uri of the remote printer instead. The attached patch solves the problem by adding a parameter for specification of the port to gtk_cups_connection_cups_new() and by specifying the port where needed.

Created attachment 280494 [details] [review]
Check connection to remote CUPS server on correct port (gtk master version)

Review of attachment 280494 [details] [review]:

makes sense to me. please put this on the 3.16 and 3.14 branches too

Review of attachment 280494 [details] [review]:

makes sense to me. please put this on the 3.16 and 3.14 branches too

Review of attachment 280493 [details] [review]:

ok.

Did these patches get lost?

Thank you for the review.
I wasn't added to CC when I've attached the patch so I missed the Matthias' review.
I've pushed the patch to 2.24, 3.14, 3.16 and master.