diff options
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/BUILDING.md | 8 | ||||
| -rw-r--r-- | docs/CHANGELOG.md | 141 | ||||
| -rw-r--r-- | docs/RELATED.md | 5 | ||||
| -rw-r--r-- | docs/SECURITY.md | 126 | ||||
| -rw-r--r-- | docs/bfs.1 | 41 |
5 files changed, 297 insertions, 24 deletions
diff --git a/docs/BUILDING.md b/docs/BUILDING.md index 025dadf..cb26059 100644 --- a/docs/BUILDING.md +++ b/docs/BUILDING.md @@ -178,11 +178,11 @@ It can be handy to generate the snapshot with a different `find` implementation But keep in mind, other `find` implementations may not be correct. To my knowledge, no other implementation passes even the POSIX-compatible subset of the tests: - $ ./tests/tests.sh --bfs=find --posix + $ ./tests/tests.sh --bfs=find --sudo --posix ... - tests passed: 90 - tests skipped: 3 - tests failed: 6 + [PASS] 104 / 119 + [SKIP] 1 / 119 + [FAIL] 14 / 119 Run diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md index 62b6480..ec3daab 100644 --- a/docs/CHANGELOG.md +++ b/docs/CHANGELOG.md @@ -1,6 +1,147 @@ +4.* +=== + +4.0.2 +----- + +**September 17, 2024** + +### New features + +- Implemented `./configure --version=X.Y.Z`, mainly for packagers to override the version number + ([`4a278d3`](https://github.com/tavianator/bfs/commit/4a278d3e39a685379711727eac7bfaa83679e0e4)) + +### Changes + +- Minor refactoring of the build system + +### Bug fixes + +- Fixed `./configure --help`, which was broken since `bfs` 4.0 + ([`07ae989`](https://github.com/tavianator/bfs/commit/07ae98906dbb0caaac2f758d72e88dd0975b2a81)) + +- Fixed compiler flag auto-detection on systems with non-GNU `sed`. + This fixes a potential race condition on FreeBSD since `bfs` 4.0 due to the [switch to `_Fork()`](https://github.com/tavianator/bfs/commit/085bb402c7b2c2f96624fb0523ff3f9686fe26d9) without passing `-z now` to the linker. + ([`34e6081`](https://github.com/tavianator/bfs/commit/34e60816adb0ea8ddb155a454676a99ab225dc8a)) + +- Fixed `$MAKE distcheck` when `$MAKE` is not `make`, e.g. `gmake distcheck` on BSD + ([`2135b00`](https://github.com/tavianator/bfs/commit/2135b00d215efc5c2c38e1abd3254baf31229ad4)) + +- Fixed some roff syntax issues in the `bfs` manpage + ([`812ecd1`](https://github.com/tavianator/bfs/commit/812ecd1feeb002252dd4d732b395d31c4179afaf)) + +- Fixed an assertion failure optimizing expressions like `bfs -not \( -prune , -type f \)` since `bfs` 3.1. + Release builds were not affected, since their assertions are disabled and the behaviour was otherwise correct. + ([`b1a9998`](https://github.com/tavianator/bfs/commit/b1a999892b9e13181ddd9a7d895f3d1c65fbb449)) + + +4.0.1 +----- + +**August 19, 2024** + +### Bug fixes + +- `bfs` no longer prints a "suppressed errors" warning unless `-noerror` is actually suppressing errors + ([`5d03c9d`](https://github.com/tavianator/bfs/commit/5d03c9d460d1c1afcdf062d494537986ce96a690)) + + +4.0 +--- + +**August 16, 2024** + +### New features + +- To match BSD `find` (and the POSIX Utility Syntax Guidelines), multiple flags can now be given in a single argument like `-LEXO2`. + Previously, you would have had to write `-L -E -X -O2`. + ([`c0fd33a`](https://github.com/tavianator/bfs/commit/c0fd33aaef5f345566a41c7c2558f27adf05558b)) + +- Explicit timestamps can now be written as `@SECONDS_SINCE_EPOCH`. + For example, `bfs -newermt @946684800` will print files modified since January 1, 2000 (UTC). + ([`c6bb003`](https://github.com/tavianator/bfs/commit/c6bb003b8882e9a16941f5803d072ec1cb728318)) + +- The new `-noerror` option suppresses all error messages during traversal. + ([#142](https://github.com/tavianator/bfs/issues/142)) + +### Changes + +- `-mount` now excludes mount points entirely, to comply with the recently published POSIX 2024 standard. + Use `-xdev` to include the mount point itself, but not its contents. + `bfs` has been warning about this change since version 1.5.1 (September 2019). + ([`33b85e1`](https://github.com/tavianator/bfs/commit/33b85e1f8769e7f75721887638ae454d109a034f)) + +- `-perm` now takes the current file creation mask into account when parsing a symbolic mode like `+rw`, as clarified by [POSIX defect 1392](https://www.austingroupbugs.net/view.php?id=1392). + This matches the behaviour of BSD `find`, contrary to the behaviour of GNU `find`. + ([`6290ce4`](https://github.com/tavianator/bfs/commit/6290ce41f3ec1f889abb881cf90ca91da869b5b2)) + +### Bug fixes + +- Fixed commands like `./configure CC=clang --enable-release` that set variables before other options + ([`49a5d48`](https://github.com/tavianator/bfs/commit/49a5d48d0a43bac313c8b8d1b167e60da9eaadf6)) + +- Fixed the build on RISC-V with GCC versions older than 14 + ([`e93a1dc`](https://github.com/tavianator/bfs/commit/e93a1dccd82f831a2f0d2cc382d8af5e1fda55ed)) + +- Fixed running `bfs` under Valgrind + ([`a01cfac`](https://github.com/tavianator/bfs/commit/a01cfacd423af28af6b7c13ba51e2395f3a52ee7)) + +- Fixed the exit code when failing to execute a non-existent command with `-exec`/`-ok` on some platforms including OpenBSD and HPPA + ([`8c130ca`](https://github.com/tavianator/bfs/commit/8c130ca0117fd225c24569be2ec16c7dc2150a13)) + +- Fixed `$LS_COLORS` case-sensitivity to match GNU ls more closely when the same extension is specified multiple times + ([`08030ae`](https://github.com/tavianator/bfs/commit/08030aea919039165c02805e8c637a9ec1ad0d70)) + +- Fixed the `-status` bar on Solaris/Illumos + + 3.* === +3.3.1 +----- + +**June 3, 2024** + +### Bug fixes + +- Reduced the scope of the symbolic link loop change in version 3.3. + `-xtype l` remains true for symbolic link loops, matching a change in GNU findutils 4.10.0. + However, `-L` will report an error, just like `bfs` prior to 3.3 and other `find` implementations, as required by POSIX. + + +3.3 +--- + +**May 28, 2024** + +### New features + +- The `-status` bar can now be toggled by `SIGINFO` (<kbd>Ctrl</kbd>+<kbd>T</kbd>) on systems that support it, and `SIGUSR1` on other systems + +- `-regextype` now supports all regex types from GNU find ([#21](https://github.com/tavianator/bfs/issues/21)) + +- File birth times are now supported on OpenBSD + +### Changes + +- Symbolic link loops are now treated like other broken links, rather than an error + +- `./configure` now expects `--with-libacl`, `--without-libcap`, etc. rather than `--enable-`/`--disable-` + +- The ` ` (space) flag is now restricted to numeric `-printf` specifiers + +### Bug fixes + +- `-regextype emacs` now supports [shy](https://www.gnu.org/software/emacs/manual/html_node/elisp/Regexp-Backslash.html#index-shy-groups) (non-capturing) groups + +- Fixed `-status` bar visual corruption when the terminal is resized + +- `bfs` now prints a reset escape sequence when terminated by a signal in the middle of colored output ([#138](https://github.com/tavianator/bfs/issues/138)) + +- `./configure CFLAGS=...` no longer overrides flags from `pkg-config` during configuration + + 3.2 --- diff --git a/docs/RELATED.md b/docs/RELATED.md index cf52b70..6e7bd38 100644 --- a/docs/RELATED.md +++ b/docs/RELATED.md @@ -25,8 +25,9 @@ These are not usually installed as the system `find`, but are designed to be `fi - [`bfs`](https://tavianator.com/projects/bfs.html) ([manual](https://man.archlinux.org/man/bfs.1), [source](https://github.com/tavianator/bfs)) - [schilytools](https://codeberg.org/schilytools/schilytools) `sfind` ([source](https://codeberg.org/schilytools/schilytools/src/branch/master/sfind)) - [BusyBox](https://busybox.net/) `find` ([manual](https://busybox.net/downloads/BusyBox.html#find), [source](https://git.busybox.net/busybox/tree/findutils/find.c)) -- [ToyBox](http://landley.net/toybox/) `find` ([manual](http://landley.net/toybox/help.html#find), [source](https://github.com/landley/toybox/blob/master/toys/posix/find.c)) -- uutils `find` ([source](https://github.com/uutils/findutils)) +- [ToyBox](https://landley.net/toybox/) `find` ([manual](http://landley.net/toybox/help.html#find), [source](https://github.com/landley/toybox/blob/master/toys/posix/find.c)) +- [Heirloom Project](https://heirloom.sourceforge.net/) `find` ([manual](https://heirloom.sourceforge.net/man/find.1.html), [source](https://github.com/eunuchs/heirloom-project/blob/master/heirloom/heirloom/find/find.c)) +- [uutils](https://uutils.github.io/) `find` ([source](https://github.com/uutils/findutils)) ## `find` alternatives diff --git a/docs/SECURITY.md b/docs/SECURITY.md new file mode 100644 index 0000000..7bcb5e6 --- /dev/null +++ b/docs/SECURITY.md @@ -0,0 +1,126 @@ +Security +======== + +Threat model +------------ + +`bfs` is a command line program running on multi-user operating systems. +Those other users may be malicious, but `bfs` should not allow them to do anything they couldn't already do. +That includes situations where one user (especially `root`) is running `bfs` on files owned or controlled by another user. + +On the other hand, `bfs` implicitly trusts the user running it. +Anyone with enough control over the command line of `bfs` or any `find`-compatible tool can wreak havoc with dangerous actions like `-exec`, `-delete`, etc. + +> [!CAUTION] +> The only untrusted input that should *ever* be passed on the `bfs` command line are **file paths**. +> It is *always* unsafe to allow *any* other part of the command line to be affected by untrusted input. +> Use the `-f` flag, or `-files0-from`, to ensure that the input is interpreted as a path. + +This still has security implications, incuding: + +- **Information disclosure:** an attacker may learn whether particular files exist by observing `bfs`'s output, exit status, or even side channels like execution time. +- **Denial of service:** large directory trees or slow/network storage may cause `bfs` to consume excessive system resources. + +> [!TIP] +> When in doubt, do not pass any untrusted input to `bfs`. + + +Executing commands +------------------ + +The `-exec` family of actions execute commands, passing the matched paths as arguments. +File names that begin with a dash may be misinterpreted as options, so `bfs` adds a leading `./` in some instances: + +```console +user@host$ bfs -execdir echo {} \; +./-rf +``` + +This might save you from accidentally running `rm -rf` (for example) when you didn't mean to. +This mitigation applies to `-execdir`, but not `-exec`, because the full path typically does not begin with a dash. +But it is possible, so be careful: + +```console +user@host$ bfs -f -rf -exec echo {} \; +-rf +``` + + +Race conditions +--------------- + +Like many programs that interface with the file system, `bfs` can be affected by race conditions—in particular, "[time-of-check to time-of-use](https://en.wikipedia.org/wiki/Time-of-check_to_time-of-use)" (TOCTTOU) issues. +For example, + +```console +user@host$ bfs / -user user -exec dangerous_command {} \; +``` + +is not guaranteed to only run `dangerous_command` on files you own, because another user may run + +```console +evil@host$ mv /path/to/file /path/to/exile +evil@host$ mv ~/malicious /path/to/file +``` + +in between checking `-user user` and executing the command. + +> [!WARNING] +> Be careful when running `bfs` on directories that other users have write access to, because they can modify the directory tree while `bfs` is running, leading to unpredictable results and possible TOCTTOU issues. + + +Output sanitization +------------------- + +In general, printing arbitrary data to a terminal may have [security](https://hdm.io/writing/termulation.txt) [implications](https://dgl.cx/2023/09/ansi-terminal-security#vulnerabilities-using-known-replies). +On many platforms, file paths may be completely arbitrary data (except for NUL (`\0`) bytes). +Therefore, when `bfs` is writing output to a terminal, it will escape non-printable characters: + +<pre> +user@host$ touch $'\e[1mBOLD\e[0m' +user@host$ bfs +. +./$'\e[1mBOLD\e[0m' +</pre> + +However, this is fragile as it only applies when outputting directly to a terminal: + +<pre> +user@host$ bfs | grep BOLD +<strong>BOLD</strong> +</pre> + + +Code quality +------------ + +Every correctness issue in `bfs` is a potential security issue, because acting on the wrong path may do arbitrarily bad things. +For example: + +```console +root@host# bfs /etc -name passwd -exec cat {} \; +``` + +should print `/etc/passwd` but not `/etc/shadow`. +`bfs` tries to ensure correct behavior through careful programming practice, an extensive testsuite, and static analysis. + +`bfs` is written in C, which is a memory unsafe language. +Bugs that lead to memory corruption are likely to be exploitable due to the nature of C. +We use [sanitizers](https://github.com/google/sanitizers) to try to detect these bugs. +Fuzzing has also been applied in the past, and deploying continuous fuzzing is a work in progress. + + +Supported versions +------------------ + +`bfs` comes with [no warranty](/LICENSE), and is maintained by [me](https://tavianator.com/) and [other volunteers](https://github.com/tavianator/bfs/graphs/contributors) in our spare time. +In that sense, there are no *supported* versions. +However, as long as I maintain `bfs` I will attempt to address any security issues swiftly. +In general, security fixes will be part of the latest release, though for significant issues I may backport fixes to older release series. + + +Reporting a vulnerability +------------------------- + +If you think you have found a sensitive security issue in `bfs`, you can [report it privately](https://github.com/tavianator/bfs/security/advisories/new). +Or you can [report it publicly](https://github.com/tavianator/bfs/issues/new); I won't judge you. @@ -1,4 +1,4 @@ -.TH BFS 1 +.TH BFS 1 2024-09-17 "bfs 4.0.1" .SH NAME bfs \- breadth-first search for your files .SH SYNOPSIS @@ -41,17 +41,17 @@ For example, .PP .nf .RS -.B bfs \\\( \-name '*.txt' \-or \-lname '*.txt' \\\\) \-and \-print +.B bfs \e( \-name '*.txt' \-or \-lname '*.txt' \e) \-and \-print .RE .fi .PP -will print the all the paths that are either .txt files or symbolic links to .txt files. +will print all the paths that are either .txt files or symbolic links to .txt files. .B \-and is implied between two consecutive expressions, so this is equivalent: .PP .nf .RS -.B bfs \\\( \-name '*.txt' \-or \-lname '*.txt' \\\\) \-print +.B bfs \e( \-name '*.txt' \-or \-lname '*.txt' \e) \-print .RE .fi .PP @@ -71,7 +71,7 @@ will also accept .I \-N or .IR +N . -.IR \-N +.I \-N means "less than .IR N ," and @@ -115,7 +115,6 @@ Don't descend into other mount points (same as \fB\-xdev\fR). Treat .I PATH as a path to search (useful if it begins with a dash). -.PP .TP \fB\-D \fIFLAG\fR Turn on a debugging flag (see @@ -188,9 +187,9 @@ threads in parallel (default: number of CPUs, up to \fB( \fIexpression \fB)\fR Parentheses are used for grouping expressions together. You'll probably have to write -.B \\\\( +.B \e( .I expression -.B \\\\) +.B \e) to avoid the parentheses being interpreted by the shell. .PP \fB! \fIexpression\fR @@ -199,7 +198,7 @@ to avoid the parentheses being interpreted by the shell. .RS The "not" operator: returns the negation of the truth value of the .IR expression . -You may have to write \fB\\! \fIexpression\fR to avoid \fB!\fR being interpreted by the shell. +You may have to write \fB\e! \fIexpression\fR to avoid \fB!\fR being interpreted by the shell. .RE .PP \fIexpression\fR \fIexpression\fR @@ -266,7 +265,6 @@ Print usage information, and exit immediately (without parsing the rest of the c Print version information, and exit immediately. .RE .SH OPTIONS -.PP .B \-color .br .B \-nocolor @@ -289,7 +287,7 @@ Follow all symbolic links (same as .BR \-L ). .TP \fB\-files0\-from \fIFILE\fR -Treat the NUL ('\\0')-separated paths in +Treat the NUL ('\e0')-separated paths in .I FILE as starting points for the search. Pass @@ -316,9 +314,10 @@ Ignore files deeper/shallower than .RE .TP .B \-mount -Don't descend into other mount points (same as -.B \-xdev -for now, but will skip mount points entirely in the future). +Exclude mount points entirely from the results. +.TP +.B \-noerror +Ignore any errors that occur during traversal. .TP .B \-nohidden Exclude hidden files and directories. @@ -381,6 +380,9 @@ Turn on or off warnings about the command line. .TP .B \-xdev Don't descend into other mount points. +Unlike +.BR \-mount , +the mount point itself is still included. .SH TESTS .TP .B \-acl @@ -479,6 +481,10 @@ Find files the current user can execute/read/write. Always false/true. .RE .TP +\fB\-flags\fR [\fI\-+\fR]\fIFLAGS\fR +Find files with matching inode +.BR FLAGS . +.TP \fB\-fstype \fITYPE\fR Find files on file systems with the given .IR TYPE . @@ -582,7 +588,7 @@ Find files whose entire path matches the .IR GLOB . .RE .TP -\fB\-perm\fR [\fI\-\fR]\fIMODE\fR +\fB\-perm\fR [\fI\-+/\fR]\fIMODE\fR Find files with a matching mode. .TP \fB\-regex \fIREGEX\fR @@ -681,7 +687,6 @@ Find files of the given type, following links when .B \-type would not, and vice versa. .SH ACTIONS -.PP .B \-delete .br .B \-rm @@ -745,7 +750,7 @@ Print the path to the found file. .B \-print0 Like .BR \-print , -but use the null character ('\\0') as a separator rather than newlines. +but use the null character ('\e0') as a separator rather than newlines. Useful in conjunction with .B xargs .IR \-0 . @@ -913,7 +918,7 @@ Finds broken symbolic links. .TP .B bfs \-name config \-exclude \-name .git Finds all files named -.BR config, +.BR config , skipping every .B .git directory. |