Wolfpack Empire - mirror of https://git.pond.sub.org/empserver
http://wolfpackempire.com/
Key 'L' copies the source sector to a destination sector. Bug: it
doesn't copy, it messes up the source sector badly instead, and can
smash the stack on some machines.
Root cause: doland() passes § instead of sect to ef_set_uid().
Impact:
1. ef_setuid() clobbers a few bytes at §.
When the bitfield and uid fit into sizeof(sect) bytes, it clobbers
just sect, which has no effect, because doland() returns without
using it again. This is the case on a typical 64-bit machine: bit
field and uid are both 4 bytes, sizeof(sect) is 8.
When they don't fit, whatever is adjacent to sect gets clobbered.
On a typical 32-bit machine with stack growing down, that's p.
Again, no effect, because doland() returns without using it again.
With stack growing up, it could well be the return address,
crashing the server.
2. ef_setuid() fails to update *sect. Impact (when we survive 1):
sect->sct_uid remains unchanged. putsect() writes to the source
sector instead of the destination sector, clobbering the source's
sct_x, sct_y. Breaks invariant sctoff(sct_x, sct_y) == sct_uid!
Subsequent edits are all applied to the source sector.
sect->sct_seqno remains unchanged. No effect, because we write to
the source sector, and the unchanged sequence number is the right
one there.
Broken in commit
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build-aux | ||
doc | ||
include | ||
info | ||
m4 | ||
man | ||
scripts | ||
src | ||
tests | ||
.gitignore | ||
.travis.yml | ||
bootstrap | ||
configure.ac | ||
COPYING | ||
CREDITS | ||
GNUmakefile.in | ||
INSTALL | ||
Make.mk | ||
README |
Welcome to Empire 4, code-named Wolfpack. Empire is a multi-player, client/server Internet based war game. Copyright (C) 1986-2013, Dave Pare, Jeff Bailey, Thomas Ruschak, Ken Stevens, Steve McClure, Markus Armbruster This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License (in file `COPYING'), or (at your option) any later version. See file `CREDITS' for a list of contributors. Directory `doc' has additional information. File `doc/README' describes the files there and what they talk about. To build the server and set up a game, follow the steps below. (1) Unpacking the source tree If you downloaded a tarball, unpack it. If you cloned a git repository, run bootstrap. This requires recent versions of Autoconf and Automake to be installed. See also doc/contributing. (2) Building a server Prerequisites: IEEE Std 1003.1-2001 (POSIX.1-2001), GNU make, a curses library, Perl, and either nroff or GNU troff (`groff'). See file `INSTALL' for detailed compilation and installation instructions. Quick guide for the impatient: run configure; make; make install. The last step is optional; everything runs fine right from the build tree. If configure reports "terminfo: no" in its configuration summary, highlighting doesn't work in the client. Commonly caused by not having development libraries installed. On Linux, try installing ncurses-devel. If make fails without doing anything, you're probably not using GNU make. Some systems have it installed as `gmake'. Solaris supports POSIX.1-2001, but you need to set up your environment for that. Try passing SHELL=/usr/xpg4/bin/sh PATH=/usr/xpg6/bin:/usr/xpg4/bin:$PATH to make. See standards(5) for details. (3) Creating a game * Create a configuration for your game. make install installs one in $prefix/etc/empire/econfig ($prefix is /usr/local unless you chose something else with configure). You can use pconfig to create another one. * Edit your configuration file. See doc/econfig for more information. Unless you put your configuration file in the default location (where make install installs it), you have to use -e with all programs to make them use your configuration. * Run files to set up your data directory. * Run fairland to create a world. For a sample world, try `fairland 10 30'. This creates file ./newcap_script, which will be used below. You can edit it to change country names and passwords. Check out fairland's manual page for more information. * Start the server. For development, you want to run it with -d in a debugger, see doc/debugging. Do not use -d for a real game! * Log in as deity POGO with password peter. This guide assumes you use the included client `empire', but other clients should work as well. For help, try `info'. To change the deity password, use `change re <password>'. * Create countries with `exec newcap_script'. Your game is now up! Naturally, there's more to running a real game than that, but that's beyond the scope of this file. Please report bugs to <wolfpack@wolfpackempire.com> or via SourceForge <http://sourceforge.net/projects/empserver/> (registration required). For more information or help, try rec.games.empire on Usenet, or send e-mail to <wolfpack@wolfpackempire.com> and we'll try to answer if we can. Also check out our web site at <http://www.wolfpackempire.com/>. Have fun! Wolfpack!