PURPOSE of /tools/glibc/Regression/bz676039-Resolver-fails-to-return-all-addresses-of
Description: Test for bz676039 (Resolver fails to return all addresses of)
Author: Miroslav Franc <mfranc@redhat.com>
Bug summary: Resolver fails to return all addresses of multi-homed hosts in /etc/hosts
Bugzilla link: https://bugzilla.redhat.com/show_bug.cgi?id=676039

Description:

getaddrinfo does not return all ip addresses on first call when name resolution is done from /etc/hosts.

This has been fixed by the following commits upstream:

1f0398248c1c581a1203c0d294acde295b949fea
1ce7d80ddc62d4bb3e8e4f89fbcb6fa21361733d

1ce7d80ddc62d4bb3e8e4f89fbcb6fa21361733d is needed because nscd links in getaddrinfo. The side-effect is that a similar bug in nscd will also be fixed (upstream bug #4814).

Private branch: private-spoyarek-ROS00401237
Build: http://brewweb.devel.redhat.com/brew/taskinfo?taskID=3051905


Customer has verified that the patch works

This issue was first reported to Oracle as a problem with Java. The public link to the report can be found here:
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7007462

Consider the following setup on RedHat Enterprise Linux 5.5 x64.
1) Add the following lines to /etc/hosts:
multihost 1.1.1.1
multihost 2.2.2.2
multihost 3.3.3.3

2) Add the following line to /etc/host.conf:
multi on

3) Compile and execute the following program (provided by Oracle Java engineering team):

/* This test code is to be used for demonstrating the
* issue associated with SR 2-8229521.
*/
#include <stdio.h>

#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <string.h>
#include <strings.h>
#include <stdlib.h>
#include <ctype.h>

void dump_res(struct addrinfo * p_res){
struct addrinfo *iter = p_res;
while(iter != 0){
struct sockaddr_in *addr1b;
addr1b = (struct sockaddr_in *)iter->ai_addr;
printf("getaddrinfo returns: %s %d %d\n", inet_ntoa(addr1b->sin_addr) , iter->ai_family, iter->ai_protocol );
iter=iter->ai_next;
}
}

int main(int argc, char *argv[]){
if (argc != 2){
printf("Usage prog hostname\n");
exit(7);
}

struct addrinfo hints, *res;
int error;

bzero(&hints, sizeof(hints));
hints.ai_flags = AI_CANONNAME;
hints.ai_family = AF_UNSPEC;

printf("======== RH BUG ===============\n");

if ( (error = getaddrinfo(argv[1], NULL, &hints, &res) ) ){
perror("getaddrinfo");
exit(-1);
}

dump_res(res);
freeaddrinfo(res);

printf("======== WORKAROUND ===============\n");

hints.ai_family = AF_INET;

if ( (error = getaddrinfo(argv[1], NULL, &hints, &res) ) ){
perror("getaddrinfo");
exit(-1);
}

dump_res(res);
freeaddrinfo(res);
}

4) You can see the following output from the above program:
# ./a.out multihost
======== RH BUG ===============
getaddrinfo returns: 1.1.1.1 2 6
getaddrinfo returns: 1.1.1.1 2 17
getaddrinfo returns: 1.1.1.1 2 0
======== WORKAROUND ===============
getaddrinfo returns: 1.1.1.1 2 6
getaddrinfo returns: 1.1.1.1 2 17
getaddrinfo returns: 1.1.1.1 2 0
getaddrinfo returns: 2.2.2.2 2 6
getaddrinfo returns: 2.2.2.2 2 17
getaddrinfo returns: 2.2.2.2 2 0
getaddrinfo returns: 3.3.3.3 2 6
getaddrinfo returns: 3.3.3.3 2 17
getaddrinfo returns: 3.3.3.3 2 0


Note that a similarly configured Ubuntu 10.10 Server (x64), provides the following - correct - output:
$ ./a.out multihost
======== RH BUG ===============
getaddrinfo returns: 1.1.1.1 2 6
getaddrinfo returns: 1.1.1.1 2 17
getaddrinfo returns: 1.1.1.1 2 0
getaddrinfo returns: 2.2.2.2 2 6
getaddrinfo returns: 2.2.2.2 2 17
getaddrinfo returns: 2.2.2.2 2 0
getaddrinfo returns: 3.3.3.3 2 6
getaddrinfo returns: 3.3.3.3 2 17
getaddrinfo returns: 3.3.3.3 2 0
======== WORKAROUND ===============
getaddrinfo returns: 1.1.1.1 2 6
getaddrinfo returns: 1.1.1.1 2 17
getaddrinfo returns: 1.1.1.1 2 0
getaddrinfo returns: 2.2.2.2 2 6
getaddrinfo returns: 2.2.2.2 2 17
getaddrinfo returns: 2.2.2.2 2 0
getaddrinfo returns: 3.3.3.3 2 6
getaddrinfo returns: 3.3.3.3 2 17
getaddrinfo returns: 3.3.3.3 2 0

In other words, hints.ai_family / hints.ai_flags for getaddrinfo are not working properly.

According to the manual of getaddrinfo (excerpts): "AF_UNSPEC in ai_family specifies any protocol family (either IPv4 or IPv6, for example)."