libdpkg: Disallow versions starting with non-digits

Fail on strict parsing, and warn otherwise.

debian/changelog

@@ -4,6 +4,8 @@ dpkg (1.16.0) UNRELEASED; urgency=low
   * Fix realloc usage on compat scandir() implementation.
   * Use DPKG_MAINTSCRIPT_PACKAGE environment variable as package name on
     dpkg-divert when no --package or --local options have been specified.
+  * Do not allow versions starting with non-digit when doing strict parsing,
+    warn otherwise.
 
   [ Raphaël Hertzog ]
   * Fail properly when debian/source/format is empty. Closes: #600854

lib/dpkg/parsehelp.c

@@ -266,7 +266,10 @@ version_strict_check(struct versionrevision *rversion)
   const char *ptr;
 
   /* XXX: Would be faster to use something like cisversion and cisrevision. */
-  for (ptr = rversion->version; *ptr; ptr++) {
+  ptr = rversion->version;
+  if (*ptr && !cisdigit(*ptr++))
+    return _("version number does not start with digit");
+  for (; *ptr; ptr++) {
     if (!cisdigit(*ptr) && !cisalpha(*ptr) && strchr(".-+~:", *ptr) == NULL)
       return _("invalid character in version number");
   }

lib/dpkg/test/t-version.c

@@ -128,8 +128,8 @@ test_version_parse(void)
 	test_pass(versioncompare(&a, &b) == 0);
 
 	/* Test valid characters in upstream version. */
-	b = version(0, "azAZ09.-+~:", "0");
-	test_pass(parseversion(&a, "0:azAZ09.-+~:-0") == NULL);
+	b = version(0, "09azAZ.-+~:", "0");
+	test_pass(parseversion(&a, "0:09azAZ.-+~:-0") == NULL);
 	test_pass(versioncompare(&a, &b) == 0);
 
 	/* Test valid characters in revision. */

scripts/t/100_Dpkg_Version.t

@@ -127,28 +127,28 @@ __DATA__
 1 0:1 0
 0 0:0-0 0
 2:2.5 1:7.5 1
-1:foo foo 1
-0:foo foo 0
-foo foo 0
-foo- foo 0
-foo- foo-0 0
-foo fo 1
-foo- foo+ -1
-foo~1 foo -1
-foo~foo+Bar foo~foo+bar -1
-foo~~ foo~ -1
+1:0foo 0foo 1
+0:0foo 0foo 0
+0foo 0foo 0
+0foo- 0foo 0
+0foo- 0foo-0 0
+0foo 0fo 1
+0foo- 0foo+ -1
+0foo~1 0foo -1
+0foo~foo+Bar 0foo~foo+bar -1
+0foo~~ 0foo~ -1
 1~ 1 -1
 12345+that-really-is-some-ver-0 12345+that-really-is-some-ver-10 -1
-foo-0 foo-01 -1
-foo.bar foobar 1
-foo.bar foo1bar 1
-foo.bar foo0bar 1
-1foo-1 foo-1 -1
-foo2.0 foo2 1
-foo2.0.0 foo2.10.0 -1
-foo2.0 foo2.0.0 -1
-foo2.0 foo2.10 -1
-foo2.1 foo2.10 -1
+0foo-0 0foo-01 -1
+0foo.bar 0foobar 1
+0foo.bar 0foo1bar 1
+0foo.bar 0foo0bar 1
+0foo1bar-1 0foobar-1 -1
+0foo2.0 0foo2 1
+0foo2.0.0 0foo2.10.0 -1
+0foo2.0 0foo2.0.0 -1
+0foo2.0 0foo2.10 -1
+0foo2.1 0foo2.10 -1
 1.09 1.9 0
 1.0.8+nmu1 1.0.8 1
 3.11 3.10+nmu1 1