On 04/23/2012 09:12 PM, Timothy Pearson wrote:
> The part I don't get is that this worked at all in KDE 3.5.10. 
> Specifically this portion of the code:
> 
>      else {
>          struct servent *pse;
>          if( (pse = getservbyname("ssh", "tcp") ) == NULL )
>              mPort = 22;
>          else
>              mPort = ntohs(pse->s_port);
>      }
> 
> looks like it should be completely removed!  This duplicates the default
> port logic in ssh (bad), and also overrides any ports set via the ssh
> option file (even worse).
> 
> I'd try removing that section of code to see if it resolves the problem.
> 
> Tim

I think you are correct. I didn't know what the hell it did, so I wrote a code
snippet to look at it and the pse structure created. What I don't get is how the
heck this would ever get the correct port since you are never providing
getservbyname with any remote host information. I run this and I get port
numbers -- but 1+1!=2 yet...:

#include <limits.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include <netdb.h>
#include <arpa/inet.h>

int getval (char *str, int base);

int main(int argc, char *argv[])
{
  int mPort;
  long port;

  if (argc < 2) {
      fprintf(stderr, "Usage: %s port_str [base]\n", argv[0]);
      exit(EXIT_FAILURE);
  }

  port = getval(argv[1], (argc > 2) ? atoi(argv[2]) : 10);

  printf("port: %d\n", port);

  struct servent *pse;
  pse = getservbyname("ssh", "tcp");

  if( port > 0 )
      mPort = port;
  else {
    if( (pse) == NULL )
      mPort = 22;
    else
      mPort = ntohs(pse->s_port);
  }

  printf("mPort: %d\n", mPort);
  printf("(servant *pse)\n\
  pse->s_name: %s\n\
  pse->s_aliases: %s\n\
  pse->s_port %d\n\
  pse->s_proto %s\n", pse->s_name, pse->s_aliases, pse->s_port, pse->s_proto);

  printf ("The host byte order -> Network byte order: %d\n\n", ntohs(pse->s_port));

  return 0;
}

int getval (char *str, int base) {

  char *endptr;
  long val;

  errno = 0;    /* To distinguish success/failure after call */
  val = strtol(str, &endptr, base);

  /* Check for various possible errors */

  if ((errno == ERANGE && (val == LONG_MAX || val == LONG_MIN))
	  || (errno != 0 && val == 0)) {
      perror("strtol");
      return(EXIT_FAILURE);
  }

  if (endptr == str) {
      fprintf(stderr, "No digits were found\n");
      return(EXIT_FAILURE);
  }

  /* If we got here, strtol() successfully parsed a number */

  printf("strtol() returned %ld\n", val);

  if (*endptr != '\0')        /* Not necessarily an error... */
      printf("Further characters after number: %s\n", endptr);

  return (val);
}


-- 
David C. Rankin, J.D.,P.E.