Commit Graph

27 Commits

Author SHA1 Message Date
pfg
872b698bd4 General further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:49:47 +00:00
imp
7e6cabd06e Renumber copyright clause 4
Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by:	Jan Schaumann <jschauma@stevens.edu>
Pull Request:	https://github.com/freebsd/freebsd/pull/96
2017-02-28 23:42:47 +00:00
jilles
aca221db9d wordexp: Rewrite to make WRDE_NOCMD reliable.
Shell syntax is too complicated to detect command substitution and unquoted
operators reliably without implementing much of sh's parser. Therefore, have
sh do this detection.

While changing sh's support anyway, also read input from a pipe instead of
arguments to avoid {ARG_MAX} limits and improve privacy, and output count
and length using 16 instead of 8 digits.

The basic concept is:
execl("/bin/sh", "sh", "-c", "freebsd_wordexp ${1:+\"$1\"} -f "$2",
    "", flags & WRDE_NOCMD ? "-p" : "", <pipe with words>);

The WRDE_BADCHAR error is still implemented in libc. POSIX requires us to
fail strings containing unquoted braces with code WRDE_BADCHAR. Since this
is normally not a syntax error in sh, there is still a need for checking
code in libc, we_check().

The new we_check() is an optimistic check that all the characters
  <newline> | & ; < > ( ) { }
are quoted. To avoid duplicating too much sh logic, such characters are
permitted when quoting characters are seen, even if the quoting characters
may themselves be quoted. This code reports all WRDE_BADCHAR errors; bad
characters that get past it and are a syntax error in sh return WRDE_SYNTAX.

Although many implementations of WRDE_NOCMD erroneously allow some command
substitutions (and ours even documented this), there appears to be code that
relies on its security (codesearch.debian.net shows quite a few uses).
Passing untrusted data to wordexp() still exposes a denial of service
possibility and a fairly large attack surface.

Reviewed by:	wblock (man page only)
MFC after:	2 weeks
Relnotes:	yes
Security:	fixes command execution with wordexp(untrusted, WRDE_NOCMD)
2015-09-30 21:32:29 +00:00
jilles
9b565c0250 sh: Allow aliases to force alias substitution on the following word.
If an alias's value ends with a space or tab, the next word is also
checked for aliases.

This is a POSIX feature. It is useful with utilities like command and
nohup (alias them to themselves followed by a space).
2014-01-26 21:19:33 +00:00
jilles
415d59b5d8 sh: Cast -1 to pointer rather than pointer to variable of wrong type.
NEOF needs to be a non-null pointer distinct from valid union node pointers.
It is not dereferenced.

The new NEOF is much like SIG_ERR except that it is an object pointer
instead of a function pointer.

The variable tokpushback can now be static.
2013-08-30 10:45:02 +00:00
jilles
e5ea815310 sh: Remove unnecessary reset functions.
These are already handled by exception handlers.
2013-08-16 20:24:41 +00:00
jilles
0ad2a46f33 sh: Remove mkinit.
Replace the RESET blocks with regular functions and a reset() function that
calls them all.

This code generation tool is unusual and does not appear to provide much
benefit. I do not think isolating the knowledge about which modules need to
be reset is worth an almost 500-line build tool and wider scope for
variables used by the reset functions.

Also, relying on reset functions is often wrong: the cleanup should be done
in exception handlers so that no stale state remains after 'command eval'
and the like.
2013-07-25 15:08:41 +00:00
jilles
3deb97fc0b sh: Fix various compiler warnings.
It now passes WARNS=7 with clang on i386.

GCC 4.2.1 does not understand setjmp() properly so will always trigger
-Wuninitialized. I will not add the volatile keywords to suppress this.
2013-04-01 17:18:22 +00:00
jilles
bb422352b5 sh: Fix a comment. 2013-02-07 21:24:10 +00:00
jilles
bd55770c94 sh: Do parameter expansion before printing PS4 (set -x).
The function name expandstr() and the general idea of doing this kind of
expansion by treating the text as a here document without end marker is from
dash.

All variants of parameter expansion and arithmetic expansion also work (the
latter is not required by POSIX but it does not take extra code and many
other shells also allow it).

Command substitution is prevented because I think it causes too much code to
be re-entered (for example creating an unbounded recursion of trace lines).

Unfortunately, our LINENO is somewhat crude, otherwise PS4='$LINENO+ ' would
be quite useful.
2011-06-09 23:12:23 +00:00
jilles
3dd8ae4222 sh: Expand aliases after assignments and redirections. 2011-05-21 22:03:06 +00:00
jilles
e4f71c5640 sh: Change the CTL* bytes to ones invalid in UTF-8.
This ensures that mbrtowc(3) can be used directly once it has been verified
that there is no CTL* byte. Dealing with a CTLESC byte within a multibyte
character would be complicated.

The new values do occur in iso-8859-* encodings. This decreases efficiency
slightly but should not affect correctness.

Caveat: Updating across this change and rebuilding without cleaning may
yield a subtly broken sh binary. By default, make buildworld will clean and
avoid problems.
2011-05-06 20:45:50 +00:00
jilles
28ad180ab4 sh: Do IFS splitting on word in ${v+word} and ${v-word}.
The code is inspired by NetBSD sh somewhat, but different because we
preserve the old Almquist/Bourne/Korn ability to have an unquoted part in a
quoted ${v+word}. For example, "${v-"*"}" expands to $v as a single field if
v is set, but generates filenames otherwise.

Note that this is the only place where we split text literally from the
script (the similar ${v=word} assigns to v and then expands $v). The parser
must now add additional markers to allow the expansion code to know whether
arbitrary characters in substitutions are quoted.

Example:
  for i in ${$+a b c}; do echo $i; done

Exp-run done by:	pav (with some other sh(1) changes)
2010-10-29 13:42:18 +00:00
jilles
5e8a2136e7 sh: Various warning fixes (from WARNS=6 NO_WERROR=1):
- const
- initializations to silence -Wuninitialized (it was safe anyway)
- remove nested extern declarations
- rename "index" locals to "idx"
2009-12-27 18:04:05 +00:00
jilles
8e458de852 sh: Constify various strings.
Most of this is adding const keywords, but setvar() in var.c had to be
changed somewhat more.
2009-12-24 18:41:14 +00:00
stefanf
91768cb1d9 Expand $LINENO to the current line number. This is required by SUSv3's "User
Portability Utilities" option.

Often configure scripts generated by the autotools test if $LINENO works and
refuse to use /bin/sh if not.

Package test run by:	pav
2008-05-15 19:55:27 +00:00
stefanf
d02f26394e When parsing an invalid parameter expansion (eg. ${} or ${foo@bar}) do not
issue a syntax error immediately but save the information that it is erroneous
for later when the parameter expansion is actually done.  This means eg. "false
&& ${}" will not generate an error which seems to be required by POSIX.
Include the invalid parameter expansion in the error message (sometimes
abbreviated with ... because recovering it would require a lot of code).

PR:		105078
Submitted by:	emaste
2006-11-05 18:36:05 +00:00
markm
4383f14801 Remove clause 3 from the UCB licenses.
OK'ed by:	imp, core
2004-04-06 20:06:54 +00:00
imp
5ef5088ac4 o __P has been reoved
o Old-style K&R declarations have been converted to new C89 style
o register has been removed
o prototype for main() has been removed (gcc3 makes it an error)
o int main(int argc, char *argv[]) is the preferred main definition.
o Attempt to not break style(9) conformance for declarations more than
  they already are.
o Change
	int
	foo() {
	...
  to
	int
	foo(void)
	{
	...
2002-02-02 06:50:57 +00:00
peter
66312e4a8d $Id$ -> $FreeBSD$ 1999-08-27 23:15:48 +00:00
tegge
ac59a0c5cd Better handling of word splitting. Don't record the same region
multiple times when performing nested variable expansion, and
preserve some quoting information in order to avoid removing
apparently empty expansion result.
1998-09-06 21:13:09 +00:00
peter
83b3c2c161 Revert $FreeBSD$ to $Id$ 1997-02-22 14:13:04 +00:00
jkh
808a36ef65 Make the long-awaited change from $Id$ to $FreeBSD$
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore.  This update would have been
insane otherwise.
1997-01-14 07:20:47 +00:00
steve
c58aca035e Merge in NetBSD mods and -Wall cleaning.
Obtained from: NetBSD, me
1996-12-14 06:20:03 +00:00
peter
5195be912e Merge of 4.4-Lite2 sh source, plus some gcc -Wall cleaning. This is a
merge of parallel duplicate work by Steve Price and myself. :-]

There are some changes to the build that are my fault...  mkinit.c was
trying (poorly) to duplicate some of the work that make(1) is designed to
do.  The Makefile hackery is my fault too, the depend list was incomplete
because of some explicit OBJS+= entries, so mkdep wasn't picking up their
source file #includes.

This closes a pile of /bin/sh PR's, but not all of them..

Submitted by: Steve Price <steve@bonsai.hiwaay.net>, peter
1996-09-01 10:22:36 +00:00
dg
8722740e7f Added $Id$ 1994-09-24 02:59:15 +00:00
rgrimes
e3cfc8ce61 BSD 4.4 Lite bin Sources 1994-05-26 06:18:55 +00:00