tar,unzip: postpone creation of symlinks with "suspicious" targets

This mostly reverts commit bc9bbeb2b81001e8731cd2ae501c8fccc8d87cc7
"libarchive: do not extract unsafe symlinks unless $EXTRACT_UNSAFE_SYMLINKS=1"

Users report that it is somewhat too restrictive. See
https://bugs.busybox.net/show_bug.cgi?id=8411

In particular, this interferes with unpacking of busybox-based
filesystems with links like "sbin/applet" -> "../bin/busybox".

The change is made smaller by deleting ARCHIVE_EXTRACT_QUIET flag -
it is unused since 2010, and removing conditionals on it
allows commonalizing some error message codes.

function                                             old     new   delta
create_or_remember_symlink                             -      94     +94
create_symlinks_from_list                              -      64     +64
tar_main                                            1002    1006      +4
unzip_main                                          2732    2724      -8
data_extract_all                                     984     891     -93
unsafe_symlink_target                                147       -    -147
------------------------------------------------------------------------------
(add/remove: 2/1 grow/shrink: 1/2 up/down: 162/-248)          Total: -86 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 5 insertions, 5 deletions

diff --git a/testsuite/tar.tests b/testsuite/tar.tests
index b7cd74ca5..1675b07b1 100755
--- a/testsuite/tar.tests
+++ b/testsuite/tar.tests
@@ -279,7 +279,7 @@ optional UUDECODE FEATURE_TAR_AUTODETECT FEATURE_SEAMLESS_BZ2
 testing "tar does not extract into symlinks" "\
 >>/tmp/passwd && uudecode -o input && tar xf input 2>&1 && rm passwd; cat /tmp/passwd; echo \$?
 " "\
-tar: skipping unsafe symlink to '/tmp/passwd' in archive, set EXTRACT_UNSAFE_SYMLINKS=1 to extract
+tar: can't create symlink 'passwd' to '/tmp/passwd'
 0
 " \
 "" "\
@@ -299,7 +299,7 @@ optional UUDECODE FEATURE_TAR_AUTODETECT FEATURE_SEAMLESS_BZ2
 testing "tar -k does not extract into symlinks" "\
 >>/tmp/passwd && uudecode -o input && tar xf input -k 2>&1 && rm passwd; cat /tmp/passwd; echo \$?
 " "\
-tar: skipping unsafe symlink to '/tmp/passwd' in archive, set EXTRACT_UNSAFE_SYMLINKS=1 to extract
+tar: can't create symlink 'passwd' to '/tmp/passwd'
 0
 " \
 "" "\
@@ -324,11 +324,11 @@ rm -rf etc usr
 ' "\
 etc/ssl/certs/3b2716e5.0
 etc/ssl/certs/EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.pem
-tar: skipping unsafe symlink to '/usr/share/ca-certificates/mozilla/EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.crt' in archive, set EXTRACT_UNSAFE_SYMLINKS=1 to extract
 etc/ssl/certs/f80cc7f6.0
 usr/share/ca-certificates/mozilla/EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.crt
 0
 etc/ssl/certs/3b2716e5.0 -> EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.pem
+etc/ssl/certs/EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.pem -> /usr/share/ca-certificates/mozilla/EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.crt
 etc/ssl/certs/f80cc7f6.0 -> EBG_Elektronik_Sertifika_Hizmet_Sağlayıcısı.pem
 " \
 "" ""
@@ -346,9 +346,9 @@ ls symlink/bb_test_evilfile
 ' "\
 anything.txt
 symlink
-tar: skipping unsafe symlink to '/tmp' in archive, set EXTRACT_UNSAFE_SYMLINKS=1 to extract
 symlink/bb_test_evilfile
-0
+tar: can't create symlink 'symlink' to '/tmp'
+1
 ls: /tmp/bb_test_evilfile: No such file or directory
 ls: bb_test_evilfile: No such file or directory
 symlink/bb_test_evilfile