Add getgids utility to simular "id -G" using sudo_getgrouplist2()

MANIFEST

@@ -237,6 +237,7 @@ lib/util/regress/fnmatch/fnm_test.in
 lib/util/regress/fuzz/fuzz_sudo_conf.c
 lib/util/regress/fuzz/fuzz_sudo_conf.dict
 lib/util/regress/getdelim/getdelim_test.c
+lib/util/regress/getgrouplist/getgids.c
 lib/util/regress/getgrouplist/getgrouplist_test.c
 lib/util/regress/glob/files
 lib/util/regress/glob/globtest.c

lib/util/Makefile.in

@@ -105,7 +105,7 @@ PVS_LOG_OPTS = -a 'GA:1,2' -e -t errorfile -d $(PVS_IGNORE)
 # Regression tests
 TEST_PROGS = conf_test hltq_test parseln_test progname_test strsplit_test \
 	     strtobool_test strtoid_test strtomode_test strtonum_test \
-	     parse_gids_test getgrouplist_test @COMPAT_TEST_PROGS@
+	     parse_gids_test getgids getgrouplist_test @COMPAT_TEST_PROGS@
 TEST_LIBS = @LIBS@
 TEST_LDFLAGS = @LDFLAGS@
 
@@ -170,6 +170,8 @@ STRSPLIT_TEST_OBJS = strsplit_test.lo strsplit.lo
 
 PARSE_GIDS_TEST_OBJS = parse_gids_test.lo gidlist.lo
 
+GETGIDS_OBJS = getgids.lo getgrouplist.lo
+
 GETGROUPLIST_TEST_OBJS = getgrouplist_test.lo getgrouplist.lo
 
 STRSIG_TEST_OBJS = strsig_test.lo sig2str.lo str2sig.lo @SIGNAME@
@@ -269,6 +271,9 @@ progname_test: $(PROGNAME_TEST_OBJS)
 parse_gids_test: $(PARSE_GIDS_TEST_OBJS) libsudo_util.la
 	$(LIBTOOL) $(LTFLAGS) --mode=link $(CC) -o $@ $(PARSE_GIDS_TEST_OBJS) libsudo_util.la $(ASAN_LDFLAGS) $(PIE_LDFLAGS) $(SSP_LDFLAGS) $(TEST_LDFLAGS) $(TEST_LIBS)
 
+getgids: $(GETGIDS_OBJS) libsudo_util.la
+	$(LIBTOOL) $(LTFLAGS) --mode=link $(CC) -o $@ $(GETGIDS_OBJS) libsudo_util.la $(ASAN_LDFLAGS) $(PIE_LDFLAGS) $(SSP_LDFLAGS) $(TEST_LDFLAGS) $(TEST_LIBS)
+
 getgrouplist_test: $(GETGROUPLIST_TEST_OBJS) libsudo_util.la
 	$(LIBTOOL) $(LTFLAGS) --mode=link $(CC) -o $@ $(GETGROUPLIST_TEST_OBJS) libsudo_util.la $(ASAN_LDFLAGS) $(PIE_LDFLAGS) $(SSP_LDFLAGS) $(TEST_LDFLAGS) $(TEST_LIBS)
 
@@ -781,12 +786,26 @@ getentropy.i: $(srcdir)/getentropy.c $(incdir)/sudo_compat.h \
 	$(CC) -E -o $@ $(CPPFLAGS) $<
 getentropy.plog: getentropy.i
 	rm -f $@; pvs-studio --cfg $(PVS_CFG) --sourcetree-root $(top_srcdir) --skip-cl-exe yes --source-file $(srcdir)/getentropy.c --i-file $< --output-file $@
+getgids.lo: $(srcdir)/regress/getgrouplist/getgids.c \
+            $(incdir)/compat/stdbool.h $(incdir)/sudo_compat.h \
+            $(incdir)/sudo_fatal.h $(incdir)/sudo_plugin.h \
+            $(incdir)/sudo_util.h $(top_builddir)/config.h
+	$(LIBTOOL) $(LTFLAGS) --mode=compile $(CC) -c -o $@ $(CPPFLAGS) $(CFLAGS) $(ASAN_CFLAGS) $(PIE_CFLAGS) $(SSP_CFLAGS) $(srcdir)/regress/getgrouplist/getgids.c
+getgids.i: $(srcdir)/regress/getgrouplist/getgids.c \
+            $(incdir)/compat/stdbool.h $(incdir)/sudo_compat.h \
+            $(incdir)/sudo_fatal.h $(incdir)/sudo_plugin.h \
+            $(incdir)/sudo_util.h $(top_builddir)/config.h
+	$(CC) -E -o $@ $(CPPFLAGS) $<
+getgids.plog: getgids.i
+	rm -f $@; pvs-studio --cfg $(PVS_CFG) --sourcetree-root $(top_srcdir) --skip-cl-exe yes --source-file $(srcdir)/regress/getgrouplist/getgids.c --i-file $< --output-file $@
 getgrouplist.lo: $(srcdir)/getgrouplist.c $(incdir)/compat/nss_dbdefs.h \
                  $(incdir)/compat/stdbool.h $(incdir)/sudo_compat.h \
+                 $(incdir)/sudo_debug.h $(incdir)/sudo_queue.h \
                  $(incdir)/sudo_util.h $(top_builddir)/config.h
 	$(LIBTOOL) $(LTFLAGS) --mode=compile $(CC) -c -o $@ $(CPPFLAGS) $(CFLAGS) $(ASAN_CFLAGS) $(PIE_CFLAGS) $(SSP_CFLAGS) $(srcdir)/getgrouplist.c
 getgrouplist.i: $(srcdir)/getgrouplist.c $(incdir)/compat/nss_dbdefs.h \
                  $(incdir)/compat/stdbool.h $(incdir)/sudo_compat.h \
+                 $(incdir)/sudo_debug.h $(incdir)/sudo_queue.h \
                  $(incdir)/sudo_util.h $(top_builddir)/config.h
 	$(CC) -E -o $@ $(CPPFLAGS) $<
 getgrouplist.plog: getgrouplist.i
@@ -1126,10 +1145,12 @@ pwrite.i: $(srcdir)/pwrite.c $(incdir)/sudo_compat.h $(top_builddir)/config.h
 pwrite.plog: pwrite.i
 	rm -f $@; pvs-studio --cfg $(PVS_CFG) --sourcetree-root $(top_srcdir) --skip-cl-exe yes --source-file $(srcdir)/pwrite.c --i-file $< --output-file $@
 rcstr.lo: $(srcdir)/rcstr.c $(incdir)/compat/stdbool.h $(incdir)/sudo_compat.h \
-          $(incdir)/sudo_util.h $(top_builddir)/config.h
+          $(incdir)/sudo_debug.h $(incdir)/sudo_queue.h $(incdir)/sudo_util.h \
+          $(top_builddir)/config.h
 	$(LIBTOOL) $(LTFLAGS) --mode=compile $(CC) -c -o $@ $(CPPFLAGS) $(CFLAGS) $(ASAN_CFLAGS) $(PIE_CFLAGS) $(SSP_CFLAGS) $(srcdir)/rcstr.c
 rcstr.i: $(srcdir)/rcstr.c $(incdir)/compat/stdbool.h $(incdir)/sudo_compat.h \
-          $(incdir)/sudo_util.h $(top_builddir)/config.h
+          $(incdir)/sudo_debug.h $(incdir)/sudo_queue.h $(incdir)/sudo_util.h \
+          $(top_builddir)/config.h
 	$(CC) -E -o $@ $(CPPFLAGS) $<
 rcstr.plog: rcstr.i
 	rm -f $@; pvs-studio --cfg $(PVS_CFG) --sourcetree-root $(top_srcdir) --skip-cl-exe yes --source-file $(srcdir)/rcstr.c --i-file $< --output-file $@

lib/util/regress/getgrouplist/getgids.c

@@ -0,0 +1,81 @@
+/*
+ * SPDX-License-Identifier: ISC
+ *
+ * Copyright (c) 2021 Todd C. Miller <Todd.Miller@sudo.ws>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#ifdef HAVE_STDBOOL_H
+# include <stdbool.h>
+#else
+# include "compat/stdbool.h"
+#endif
+#include <unistd.h>
+#include <pwd.h>
+#include <grp.h>
+
+#define SUDO_ERROR_WRAP 0
+
+#include "sudo_compat.h"
+#include "sudo_fatal.h"
+#include "sudo_util.h"
+
+sudo_dso_public int main(int argc, char *argv[]);
+
+/*
+ * Implement "id -G" using sudo_getgrouplist2().
+ */
+
+int
+main(int argc, char *argv[])
+{
+    char *username = NULL;
+    GETGROUPS_T *groups = NULL;
+    struct passwd *pw;
+    int i, ngroups;
+    gid_t basegid;
+    initprogname(argc > 0 ? argv[0] : "getgids");
+
+    if (getopt(argc, argv, "") != -1) {
+	fprintf(stderr, "usage: %s [user]\n", getprogname());
+	return EXIT_FAILURE;
+    }
+    if (argc > 1)
+	username = argv[1];
+
+    if (username != NULL) {
+	if ((pw = getpwnam(username)) == NULL)
+	    sudo_fatalx("unknown user name %s", username);
+    } else {
+	if ((pw = getpwuid(getuid())) == NULL)
+	    sudo_fatalx("unknown user ID %u", (unsigned int)getuid());
+    }
+    basegid = pw->pw_gid;
+    if ((username = strdup(pw->pw_name)) == NULL)
+	sudo_fatal(NULL);
+
+    if (sudo_getgrouplist2(username, basegid, &groups, &ngroups) == -1)
+	sudo_fatal("sudo_getgroulist2");
+
+    for (i = 0; i < ngroups; i++) {
+	printf("%s%u", i ? " " : "", (unsigned int)groups[i]);
+    }
+    putchar('\n');
+    return EXIT_SUCCESS;
+}