Tim Smith:
> Hi Wietse,
>
> Actually this is one of the first things I checked and it's already in
> there. My distro is Ubuntu 12.04.4.
FYI, Postfix does not do these lookups. These lookups are
done by the system library.
You can test this with the attached getaddrinfo and getnameinfo
programs. These invoke the same library routines as Postfix.
If their output is "incomplete" then you know who to blame.
Wietse
/*
* getaddrinfo(3) (name->address lookup) tester.
*
* Compile with:
*
* cc -o getaddrinfo getaddrinfo.c (BSD, Linux)
*
* cc -o getaddrinfo getaddrinfo.c -lsocket -lnsl (SunOS 5.x)
*
* Run as: getaddrinfo hostname
*
* Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
*
* Author: Wietse Venema, IBM T.J. Watson Research, USA.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
int main(int argc, char **argv)
{
char hostbuf[NI_MAXHOST]; /* XXX */
struct addrinfo hints;
struct addrinfo *res0;
struct addrinfo *res;
const char *addr;
int err;
#define NO_SERVICE ((char *) 0)
if (argc != 2) {
fprintf(stderr, "usage: %s hostname\n", argv[0]);
exit(1);
}
memset((char *) &hints, 0, sizeof(hints));
hints.ai_family = PF_UNSPEC;
hints.ai_flags = AI_CANONNAME;
hints.ai_socktype = SOCK_STREAM;
if ((err = getaddrinfo(argv[1], NO_SERVICE, &hints, &res0)) != 0) {
fprintf(stderr, "host %s not found: %s\n", argv[1], gai_strerror(err));
exit(1);
}
printf("Hostname:\t%s\n", res0->ai_canonname);
printf("Addresses:\t");
for (res = res0; res != 0; res = res->ai_next) {
addr = (res->ai_family == AF_INET ?
(char *) &((struct sockaddr_in *) res->ai_addr)->sin_addr :
(char *) &((struct sockaddr_in6 *) res->ai_addr)->sin6_addr);
if (inet_ntop(res->ai_family, addr, hostbuf, sizeof(hostbuf)) == 0) {
perror("inet_ntop:");
exit(1);
}
printf("%s ", hostbuf);
}
printf("\n");
freeaddrinfo(res0);
exit(0);
}
/*
* getnameinfo(3) (address->name lookup) tester.
*
* Compile with:
*
* cc -o getnameinfo getnameinfo.c (BSD, Linux)
*
* cc -o getnameinfo getnameinfo.c -lsocket -lnsl (SunOS 5.x)
*
* Run as: getnameinfo address
*
* Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
*
* Author: Wietse Venema, IBM T.J. Watson Research, USA.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
int main(int argc, char **argv)
{
char hostbuf[NI_MAXHOST]; /* XXX */
struct addrinfo hints;
struct addrinfo *res0;
struct addrinfo *res;
const char *host;
const char *addr;
int err;
#define NO_SERVICE ((char *) 0)
if (argc != 2) {
fprintf(stderr, "usage: %s ipaddres\n", argv[0]);
exit(1);
}
/*
* Convert address to internal form.
*/
host = argv[1];
memset((char *) &hints, 0, sizeof(hints));
hints.ai_family = (strchr(host, ':') ? AF_INET6 : AF_INET);
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags |= AI_NUMERICHOST;
if ((err = getaddrinfo(host, NO_SERVICE, &hints, &res0)) != 0) {
fprintf(stderr, "getaddrinfo %s: %s\n", host, gai_strerror(err));
exit(1);
}
/*
* Convert host address to name.
*/
for (res = res0; res != 0; res = res->ai_next) {
err = getnameinfo(res->ai_addr, res->ai_addrlen,
hostbuf, sizeof(hostbuf),
NO_SERVICE, 0, NI_NAMEREQD);
if (err) {
fprintf(stderr, "getnameinfo %s: %s\n", host, gai_strerror(err));
exit(1);
}
printf("Hostname:\t%s\n", hostbuf);
addr = (res->ai_family == AF_INET ?
(char *) &((struct sockaddr_in *) res->ai_addr)->sin_addr :
(char *) &((struct sockaddr_in6 *) res->ai_addr)->sin6_addr);
if (inet_ntop(res->ai_family, addr, hostbuf, sizeof(hostbuf)) == 0) {
perror("inet_ntop:");
exit(1);
}
printf("Address:\t%s\n", hostbuf);
}
freeaddrinfo(res0);
exit(0);
}
