From: Pádraig Brady Date: Sat, 11 Sep 2021 15:19:39 +0000 (+0100) Subject: cksum: support digest detection for tagged format X-Git-Tag: v9.0~35 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=772173a8328ffdbde7a6639f456b36a5522e60bc;p=thirdparty%2Fcoreutils.git cksum: support digest detection for tagged format Support `cksum --check FILE` without having to specify a digest algorithm, allowing for more generic file check instructions. This also supports mixed digest checksum files, supporting more robust multi digest checks. * src/digest.c (algorithm_from_tag): A new function to identify the digest algorithm from a tagged format line. (split3): Set the algorithm depending on tag, and update the expected digest length accordingly. * tests/misc/cksum-c.sh: Add a new test. * tests/local.mk: Reference the new test. * tests/misc/md5sum.pl: Adjust to more generic error. * tests/misc/sha1sum.pl: Likewise. * doc/coreutils.texi (md5sum invocation): Mention the new -c feature. * NEWS: Mention the new feature. --- diff --git a/NEWS b/NEWS index 217cf987c0..b7d770bc3e 100644 --- a/NEWS +++ b/NEWS @@ -95,6 +95,9 @@ GNU coreutils NEWS -*- outline -*- cksum -a now supports the 'sm3' argument, to use the SM3 digest algorithm. + cksum --check now supports auto detecting the digest type to use, + when verifying tagged format checksums. + expr and factor now support bignums on all platforms. ls --classify now supports the "always", "auto", or "never" flags, diff --git a/doc/coreutils.texi b/doc/coreutils.texi index 183dde12cc..a5537d7897 100644 --- a/doc/coreutils.texi +++ b/doc/coreutils.texi @@ -4087,10 +4087,16 @@ Read file names and checksum information (not data) from each whether the checksums match the contents of the named files. The input to this mode of @command{md5sum} is usually the output of a prior, checksum-generating run of @samp{md5sum}. + Three input formats are supported. Either the default output format described above, the @option{--tag} output format, or the BSD reversed mode format which is similar to the default mode, but doesn't use a character to distinguish binary and text modes. + +For the @command{cksum} command, the @option{--check} option +supports auto-detecting the digest algorithm to use, +when presented with checksum information in the @option{--tag} output format. + Output with @option{--zero} enabled is not supported by @option{--check}. @sp 1 For each such line, @command{md5sum} reads the named file and computes its diff --git a/src/digest.c b/src/digest.c index 57b37c782b..c785751c14 100644 --- a/src/digest.c +++ b/src/digest.c @@ -311,6 +311,7 @@ static int const algorithm_bits[] = verify (ARRAY_CARDINALITY (algorithm_bits) == ARRAY_CARDINALITY (algorithm_args)); +static bool algorithm_specified = false; static enum Algorithm cksum_algorithm = crc; static sumfn cksumfns[]= { @@ -630,6 +631,45 @@ bsd_split_3 (char *s, size_t s_len, unsigned char **hex_digest, return hex_digits (*hex_digest); } +#if HASH_ALGO_CKSUM +/* Return the corresponding Algorithm for the string S, + or -1 for no match. */ + +static ptrdiff_t +algorithm_from_tag (char *s) +{ + /* Limit check size to this length for perf reasons. */ + static size_t max_tag_len; + if (! max_tag_len) + { + char const * const * tag = algorithm_tags; + while (*tag) + { + size_t tag_len = strlen (*tag++); + max_tag_len = MAX (tag_len, max_tag_len); + } + } + + size_t i = 0; + + /* Find end of tag */ + while (i <= max_tag_len && s[i] && ! ISWHITE (s[i]) + && s[i] != '-' && s[i] != '(') + ++i; + + if (i > max_tag_len) + return -1; + + /* Terminate tag, and lookup. */ + char sep = s[i]; + s[i] = '\0'; + ptrdiff_t algo = argmatch (s, algorithm_tags, NULL, 0); + s[i] = sep; + + return algo; +} +#endif + /* Split the string S (of length S_LEN) into three parts: a hexadecimal digest, binary flag, and the file name. S is modified. Return true if successful. */ @@ -653,6 +693,21 @@ split_3 (char *s, size_t s_len, /* Check for BSD-style checksum line. */ +#if HASH_ALGO_CKSUM + if (! algorithm_specified) + { + ptrdiff_t algo_tag = algorithm_from_tag (s+i); + if (algo_tag >= 0) + { + if (algo_tag <= crc) + return false; /* We don't support checking these older formats. */ + cksum_algorithm = algo_tag; + } + else + return false; /* We only support tagged format without -a. */ + } +#endif + algo_name_len = strlen (DIGEST_TYPE_STRING); if (STREQ_LEN (s + i, DIGEST_TYPE_STRING, algo_name_len)) { @@ -687,7 +742,14 @@ split_3 (char *s, size_t s_len, # if HASH_ALGO_CKSUM } # endif +# if HASH_ALGO_CKSUM + if (cksum_algorithm == blake2b) + digest_hex_bytes = b2_length / 4; + else + digest_hex_bytes = algorithm_bits[cksum_algorithm] / 4; +# else digest_hex_bytes = b2_length / 4; +# endif #endif if (s[i] == ' ') ++i; @@ -1102,8 +1164,8 @@ digest_check (char const *checkfile_name) if (! properly_formatted_lines) { /* Warn if no tests are found. */ - error (0, 0, _("%s: no properly formatted %s checksum lines found"), - quotef (checkfile_name), DIGEST_TYPE_STRING); + error (0, 0, _("%s: no properly formatted checksum lines found"), + quotef (checkfile_name)); } else { @@ -1190,6 +1252,7 @@ main (int argc, char **argv) case 'a': cksum_algorithm = XARGMATCH ("--algorithm", optarg, algorithm_args, algorithm_types); + algorithm_specified = true; break; case DEBUG_PROGRAM_OPTION: @@ -1303,7 +1366,7 @@ main (int argc, char **argv) if (prefix_tag) die (EXIT_FAILURE, 0, _("--tag is not supported with --algorithm={bsd,sysv,crc}")); - if (do_check) + if (do_check && algorithm_specified) die (EXIT_FAILURE, 0, _("--check is not supported with --algorithm={bsd,sysv,crc}")); break; diff --git a/tests/local.mk b/tests/local.mk index 192c0d31c9..228d0e3688 100644 --- a/tests/local.mk +++ b/tests/local.mk @@ -290,6 +290,7 @@ all_tests = \ tests/misc/chroot-fail.sh \ tests/misc/cksum.sh \ tests/misc/cksum-a.sh \ + tests/misc/cksum-c.sh \ tests/misc/comm.pl \ tests/misc/csplit.sh \ tests/misc/csplit-1000.sh \ diff --git a/tests/misc/cksum-c.sh b/tests/misc/cksum-c.sh new file mode 100755 index 0000000000..d8d26d8139 --- /dev/null +++ b/tests/misc/cksum-c.sh @@ -0,0 +1,59 @@ +#!/bin/sh +# Validate cksum --check dynamic operation + +# Copyright (C) 2021 Free Software Foundation, Inc. + +# 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, or +# (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. + +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src +print_ver_ cksum shuf + +shuf -i 1-10 > input || framework_failure_ + +for args in '-a sha384' '-a blake2b' '-a blake2b -l 384' '-a sm3'; do + cksum $args --tag 'input' >> CHECKSUMS || fail=1 +done +cksum --strict --check CHECKSUMS || fail=1 + +# Ensure leading whitespace and \ ignored +sed 's/^/ \\/' CHECKSUMS | cksum --strict -c || fail=1 + +# Check common signed checksums format works in non strict mode +cat >> signed_CHECKSUMS <<\EOF +-----BEGIN PGP SIGNED MESSAGE----- +Hash: SHA384 + +# ignored comment +EOF +cat CHECKSUMS >> signed_CHECKSUMS +cat >> signed_input <<\EOF +-----BEGIN PGP SIGNATURE----- + +# Note base64 doesn't have ambiguous delimiters in its charset +SHA384+BCAAdFiEEjFummQvbJuGfKhqAEWGuaUVxmjkFAmCDId0ACgkQEWGuaUVx +BLAKE2b/00001EuON62pTEnqrJ5lav61QxRByiuDp/6VODrRL2JWM6Stxu1Myws= +=AWU7 +-----END PGP SIGNATURE----- +EOF +cksum --check signed_CHECKSUMS || fail=1 + +# Can check individual digests in a mixed file +cksum --check -a sm3 CHECKSUMS || fail=1 + +# Checks against older (non hex) checksum formats not supported +returns_ 1 cksum -a crc -c CHECKSUMS || fail=1 +cksum -a crc 'input' > CHECKSUMS.crc || fail=1 +returns_ 1 cksum -c CHECKSUMS.crc || fail=1 + +Exit $fail diff --git a/tests/misc/md5sum.pl b/tests/misc/md5sum.pl index 695acba65e..c32dac0e18 100755 --- a/tests/misc/md5sum.pl +++ b/tests/misc/md5sum.pl @@ -105,7 +105,7 @@ my @Tests = ['check-bsd', '--check', {IN=> {'f.sha1' => "SHA1 (f) = $degenerate\n"}}, {AUX=> {f=> ''}}, {ERR=>"md5sum: f.sha1: no properly formatted " - . "MD5 checksum lines found\n"}, + . "checksum lines found\n"}, {EXIT=> 1}], ['check-bsd2', '--check', {IN=> {'f.md5' => "MD5 (f) = $degenerate\n"}}, {AUX=> {f=> ''}}, {OUT=>"f: OK\n"}], @@ -115,7 +115,7 @@ my @Tests = ['check-openssl', '--check', {IN=> {'f.sha1' => "SHA1(f)= $degenerate\n"}}, {AUX=> {f=> ''}}, {ERR=>"md5sum: f.sha1: no properly formatted " - . "MD5 checksum lines found\n"}, + . "checksum lines found\n"}, {EXIT=> 1}], ['check-openssl2', '--check', {IN=> {'f.md5' => "MD5(f)= $degenerate\n"}}, {AUX=> {f=> ''}}, {OUT=>"f: OK\n"}], @@ -157,7 +157,7 @@ my @Tests = "006999e6df389641adf1fa3a74801d9d f\n"}}, {OUT=>"f: OK\n"}], ['bsd-segv', '--check', {IN=> {'z' => "MD5 ("}}, {EXIT=> 1}, - {ERR=> "$prog: z: no properly formatted MD5 checksum lines found\n"}], + {ERR=> "$prog: z: no properly formatted checksum lines found\n"}], # Ensure that when there's a NUL byte among the checksum hex digits # we detect the invalid formatting and don't even open the file. @@ -165,7 +165,7 @@ my @Tests = # h: FAILED # md5sum: WARNING: 1 of 1 computed checksum did NOT match ['nul-in-cksum', '--check', {IN=> {'h'=>("\0"x32)." h\n"}}, {EXIT=> 1}, - {ERR=> "$prog: h: no properly formatted MD5 checksum lines found\n"}], + {ERR=> "$prog: h: no properly formatted checksum lines found\n"}], ); # Insert the '--text' argument for each test. diff --git a/tests/misc/sha1sum.pl b/tests/misc/sha1sum.pl index 8e33aba6fd..abbda1c498 100755 --- a/tests/misc/sha1sum.pl +++ b/tests/misc/sha1sum.pl @@ -54,7 +54,7 @@ my @Tests = ['check-bsd', '--check', {IN=> {'f.md5' => "MD5 (f) = $sha_degenerate\n"}}, {AUX=> {f=> ''}}, {ERR=>"sha1sum: f.md5: no properly formatted " - . "SHA1 checksum lines found\n"}, + . "checksum lines found\n"}, {EXIT=> 1}], ['check-bsd2', '--check', {IN=> {'f.sha1' => "SHA1 (f) = $sha_degenerate\n"}}, @@ -66,7 +66,7 @@ my @Tests = {IN=> {'f.md5' => "MD5(f)= $sha_degenerate\n"}}, {AUX=> {f=> ''}}, {ERR=>"sha1sum: f.md5: no properly formatted " - . "SHA1 checksum lines found\n"}, + . "checksum lines found\n"}, {EXIT=> 1}], ['check-openssl2', '--check', {IN=> {'f.sha1' => "SHA1(f)= $sha_degenerate\n"}}, @@ -75,7 +75,7 @@ my @Tests = {IN=> {'f.sha1' => "SHA1(f)= $sha_degenerate\n"}}, {AUX=> {f=> 'bar'}}, {EXIT=> 1}], ['bsd-segv', '--check', {IN=> {'z' => "SHA1 ("}}, {EXIT=> 1}, - {ERR=> "$prog: z: no properly formatted SHA1 checksum lines found\n"}], + {ERR=> "$prog: z: no properly formatted checksum lines found\n"}], ); # Insert the '--text' argument for each test.