md5: fix *sum -c with missing files

If we fail to open one of the files in the file listing, we still need
to advance `rec` along with `argv` so that the checksum we're checking
against lines up with the file we're hashing.

Tests added both for the -c flag, as well as the -b and -t modes of
the *sum programs.

PR:		267722
Reviewed by:	emaste (earlier version)
MFC after:	3 days
Differential Revision:	https://reviews.freebsd.org/D37374

sbin/md5/md5.c

@@ -368,6 +368,8 @@ main(int argc, char *argv[])
 			if ((fd = open(*argv, O_RDONLY)) < 0) {
 				warn("%s", *argv);
 				failed++;
+				if (cflag && gnu_emu)
+					rec = rec->next;
 				continue;
 			}
 			/*

sbin/md5/tests/Makefile

@@ -11,7 +11,7 @@ TEST_DIR=		${SRCTOP}/sbin/md5/tests
 FILESGROUPS+=		FILESinputs
 FILESinputsPACKAGE=	${PACKAGE}
 FILESinputsDIR=		${TESTSDIR}
-FILESinputs!=		echo ${TEST_DIR}/*.inp
+FILESinputs!=		echo ${TEST_DIR}/*.inp ${TEST_DIR}/*.in
 
 FILESGROUPS+=		FILESchkfiles
 FILESchkfilesPACKAGE=	${PACKAGE}
@@ -28,6 +28,8 @@ FILESparamPACKAGE=	${PACKAGE}
 FILESparamDIR=		${TESTSDIR}
 FILESparam!=		echo ${TEST_DIR}/*.txt
 
+ATF_TESTS_SH+=		md5_test
+
 PLAIN_TESTS_SH+=	self-test
 PLAIN_TESTS_SH+=	bsd-c-test
 PLAIN_TESTS_SH+=	bsd-p-test

sbin/md5/tests/md5_test.sh

@@ -0,0 +1,82 @@
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2022 Kyle Evans <kevans@FreeBSD.org>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+
+atf_test_case sum_bflag
+sum_bflag_body()
+{
+	cp $(atf_get_srcdir)/sum_a.in a
+	cp $(atf_get_srcdir)/sum_a.in b
+
+	(sha256 -q a | tr -d '\n'; echo " *a") > expected
+	(sha256 -q b | tr -d '\n'; echo " *b") >> expected
+
+	atf_check -o file:expected sha256sum -b a b
+}
+
+atf_test_case sum_cflag
+sum_cflag_body()
+{
+
+	# Verify that the *sum -c mode works even if some files are missing.
+	# PR 267722 identified that we would never advance past the first record
+	# to check against.  As a result, things like checking the published
+	# checksums for the install media became a more manual process again if
+	# you didn't download all of the images.
+	for combo in "a b c" "b c" "a c" "a b" "a" "b" "c" ""; do
+		rm -f a b c
+		:> out
+		cnt=0
+		for f in ${combo}; do
+			cp $(atf_get_srcdir)/sum_${f}.in ${f}
+			printf "${f}: OK\n" >> out
+			cnt=$((cnt + 1))
+		done
+
+		err=0
+		[ "$cnt" -eq 3 ] || err=1
+		atf_check -o file:out -e ignore -s exit:${err} \
+		    sha256sum -c $(atf_get_srcdir)/sum_sums.digest
+	done
+
+}
+
+atf_test_case sum_tflag
+sum_tflag_body()
+{
+	cp $(atf_get_srcdir)/sum_a.in a
+
+	# -t is a nop, not a time trial, when used with the *sum versions
+	(sha256 -q a | tr -d '\n'; echo "  a") > expected
+	atf_check -o file:expected sha256sum -t a
+}
+
+atf_init_test_cases()
+{
+	atf_add_test_case sum_bflag
+	atf_add_test_case sum_cflag
+	atf_add_test_case sum_tflag
+}

sbin/md5/tests/sum_a.in

@@ -0,0 +1 @@
+foo

sbin/md5/tests/sum_b.in

@@ -0,0 +1 @@
+bar

sbin/md5/tests/sum_c.in

@@ -0,0 +1 @@
+baz

sbin/md5/tests/sum_sums.digest

@@ -0,0 +1,3 @@
+SHA256 (a) = b5bb9d8014a0f9b1d61e21e796d78dccdf1352f23cd32812f4850b878ae4944c
+SHA256 (b) = 7d865e959b2466918c9863afca942d0fb89d7c9ac0c99bafc3749504ded97730
+SHA256 (c) = bf07a7fbb825fc0aae7bf4a1177b2b31fcf8a3feeaf7092761e18c859ee52a9c