munpack of Unix-mpack-1.6 can't unpack multiparts (+ patch)

[Ignatios Souvatzis]

munpack-1.6 can't overwrite its own counter file CT:

Script started on Tue Dec 14 14:48:29 2010
pkg_comp:default.conf# ./munpack foo.01

Saving part 1 of 3 13411.12...@marie.subetha
pkg_comp:default.conf# ./munpack foo.02

/var/tmp//m-prts-is/13411.12...@marie.subetha/CT: File exists
Did not find anything to unpack from foo.02
pkg_comp:default.conf# exit

Script done on Tue Dec 14 14:48:53 2010

That's because it's using O_CREAT|O_EXCL fo that one, too. My
proposed patch fixes this and makes sure the same total number is
used in all parts. This patch is also currently used by the mpack
package of pkgsrc.org.

Here's the patch:

$NetBSD: patch-ag,v 1.1 2010/11/17 22:24:40 is Exp $

--- decode.c.orig 2003-07-21 20:47:54.000000000 +0000
+++ decode.c
@@ -25,6 +25,7 @@
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE. */

+#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
@@ -601,7 +602,7 @@ int handlePartial(struct part *inpart, c
{
char *id, *dir, *p;
int thispart;
- int nparts = 0;
+ int nparts = 0, onparts=0;
char buf[1024];
FILE *partfile, *outfile;
struct part *outpart;
@@ -624,33 +625,44 @@ int handlePartial(struct part *inpart, c
}
thispart = atoi(p);

+ /* Try to retrieve number of parts from reassembly directory */
+ sprintf(buf, "%sCT", dir);
+ if (partfile = fopen(buf, "r")) {
+ if (fgets(buf, sizeof(buf), partfile)) {
+ onparts = atoi(buf);
+ if (onparts < 0) onparts = 0;
+ }
+ fclose(partfile);
+ }
+
if (p = getParam(contentParams, "total")) {
nparts = atoi(p);
if (nparts <= 0) {
warn("partial message has invalid number of parts");
goto ignore;
}
- /* Store number of parts in reassembly directory */
- sprintf(buf, "%sCT", dir);
- partfile = os_createnewfile(buf);
- if (!partfile) {
- os_perror(buf);
+ if (onparts && nparts && nparts != onparts) {
+ warn("messages disagree about total number of parts");
goto ignore;
}
- fprintf(partfile, "%d\n", nparts);
- fclose(partfile);
- }
- else {
- /* Try to retrieve number of parts from reassembly directory */
+
+ /* Store number of parts in reassembly directory */
sprintf(buf, "%sCT", dir);
- if (partfile = fopen(buf, "r")) {
- if (fgets(buf, sizeof(buf), partfile)) {
- nparts = atoi(buf);
- if (nparts < 0) nparts = 0;
+ partfile = fopen(buf, "w");
+ if (!partfile) {
+ if (errno != EEXIST) {
+ os_perror(buf);
+ goto ignore;
}
+ onparts = nparts;
+ } else {
+ fprintf(partfile, "%d\n", nparts);
fclose(partfile);
}
}
+ else {
+ nparts = onparts;
+ }

/* Sanity check */
if (thispart <= 0 || (nparts && thispart > nparts)) {
Regards,
Ignatios Souvatzis
--
seal your e-mail: http://www.gnupg.org/