nss: getent: Print IPv6 scope ID for ahosts/ahostsv6 if available
Commit Message
* Adhemerval Zanella:
>>>> +
>>>> + printf ("%s%-*s %-6s %s\n",
>>>> + buf, pad, scope, sockstr, runp->ai_canonname ?: "");
>>>
>>> Do we need to print the scope for invalid address as well?
>>
>> No, I think the invalid address can only happen (theoretically) for an
>> unexpected address family from getaddrinfo.
>
> Right, so in this case shouldn't we just print 'buf' without 'scope'
> then?
Like this?
I'll commit it after testing (manually).
Thanks,
Florian
nss: getent: Print IPv6 scope ID for ahosts/ahostsv6 if available
This information is sometimes useful and actually required for
link-local addresses.
2019-02-11 Florian Weimer <fweimer@redhat.com>
* nss/getent.c (ahosts_keys_int): Include IPv6 scope ID in output.
Comments
On 11/02/2019 10:52, Florian Weimer wrote:
> * Adhemerval Zanella:
>
>>>>> +
>>>>> + printf ("%s%-*s %-6s %s\n",
>>>>> + buf, pad, scope, sockstr, runp->ai_canonname ?: "");
>>>>
>>>> Do we need to print the scope for invalid address as well?
>>>
>>> No, I think the invalid address can only happen (theoretically) for an
>>> unexpected address family from getaddrinfo.
>>
>> Right, so in this case shouldn't we just print 'buf' without 'scope'
>> then?
>
> Like this?
>
> I'll commit it after testing (manually).
LGTM, thanks.
>
> Thanks,
> Florian
>
> nss: getent: Print IPv6 scope ID for ahosts/ahostsv6 if available
>
> This information is sometimes useful and actually required for
> link-local addresses.
>
> 2019-02-11 Florian Weimer <fweimer@redhat.com>
>
> * nss/getent.c (ahosts_keys_int): Include IPv6 scope ID in output.
>
> diff --git a/nss/getent.c b/nss/getent.c
> index f25de8f1fc..07a7d09795 100644
> --- a/nss/getent.c
> +++ b/nss/getent.c
> @@ -40,6 +40,7 @@
> #include <netinet/in.h>
> #include <sys/socket.h>
> #include <scratch_buffer.h>
> +#include <inttypes.h>
>
> /* Get libc version number. */
> #include <version.h>
> @@ -393,15 +394,34 @@ ahosts_keys_int (int af, int xflags, int number, char *key[])
> sockstr = sockbuf;
> }
>
> + /* Three digits per byte, plus '%' and null terminator. */
> + char scope[3 * sizeof (uint32_t) + 2];
> + struct sockaddr_in6 *addr6
> + = (struct sockaddr_in6 *) runp->ai_addr;
> + if (runp->ai_family != AF_INET6 || addr6->sin6_scope_id == 0)
> + /* No scope ID present. */
> + scope[0] = '\0';
> + else
> + snprintf (scope, sizeof (scope), "%%%" PRIu32,
> + addr6->sin6_scope_id);
> +
> char buf[INET6_ADDRSTRLEN];
> - printf ("%-15s %-6s %s\n",
> - inet_ntop (runp->ai_family,
> - runp->ai_family == AF_INET
> - ? (void *) &((struct sockaddr_in *) runp->ai_addr)->sin_addr
> - : (void *) &((struct sockaddr_in6 *) runp->ai_addr)->sin6_addr,
> - buf, sizeof (buf)),
> - sockstr,
> - runp->ai_canonname ?: "");
> + if (inet_ntop (runp->ai_family,
> + runp->ai_family == AF_INET
> + ? (void *) &((struct sockaddr_in *) runp->ai_addr)->sin_addr
> + : &addr6->sin6_addr,
> + buf, sizeof (buf)) == NULL)
> + {
> + strcpy (buf, "<invalid>");
> + scope[0] = '\0';
> + }
> +
> + int pad = 15 - strlen (buf) - strlen (scope);
> + if (pad < 0)
> + pad = 0;
> +
> + printf ("%s%-*s %-6s %s\n",
> + buf, pad, scope, sockstr, runp->ai_canonname ?: "");
>
> runp = runp->ai_next;
> }
>
@@ -40,6 +40,7 @@
#include <netinet/in.h>
#include <sys/socket.h>
#include <scratch_buffer.h>
+#include <inttypes.h>
/* Get libc version number. */
#include <version.h>
@@ -393,15 +394,34 @@ ahosts_keys_int (int af, int xflags, int number, char *key[])
sockstr = sockbuf;
}
+ /* Three digits per byte, plus '%' and null terminator. */
+ char scope[3 * sizeof (uint32_t) + 2];
+ struct sockaddr_in6 *addr6
+ = (struct sockaddr_in6 *) runp->ai_addr;
+ if (runp->ai_family != AF_INET6 || addr6->sin6_scope_id == 0)
+ /* No scope ID present. */
+ scope[0] = '\0';
+ else
+ snprintf (scope, sizeof (scope), "%%%" PRIu32,
+ addr6->sin6_scope_id);
+
char buf[INET6_ADDRSTRLEN];
- printf ("%-15s %-6s %s\n",
- inet_ntop (runp->ai_family,
- runp->ai_family == AF_INET
- ? (void *) &((struct sockaddr_in *) runp->ai_addr)->sin_addr
- : (void *) &((struct sockaddr_in6 *) runp->ai_addr)->sin6_addr,
- buf, sizeof (buf)),
- sockstr,
- runp->ai_canonname ?: "");
+ if (inet_ntop (runp->ai_family,
+ runp->ai_family == AF_INET
+ ? (void *) &((struct sockaddr_in *) runp->ai_addr)->sin_addr
+ : &addr6->sin6_addr,
+ buf, sizeof (buf)) == NULL)
+ {
+ strcpy (buf, "<invalid>");
+ scope[0] = '\0';
+ }
+
+ int pad = 15 - strlen (buf) - strlen (scope);
+ if (pad < 0)
+ pad = 0;
+
+ printf ("%s%-*s %-6s %s\n",
+ buf, pad, scope, sockstr, runp->ai_canonname ?: "");
runp = runp->ai_next;
}