Add simple regress check to display the network interfaces found.

MANIFEST

@@ -1103,6 +1103,7 @@ src/openbsd.c
 src/parse_args.c
 src/preload.c
 src/preserve_fds.c
+src/regress/net_ifs/check_net_ifs.c
 src/regress/noexec/check_noexec.c
 src/regress/ttyname/check_ttyname.c
 src/selinux.c

src/Makefile.in

@@ -113,7 +113,7 @@ INIT_DIR=@INIT_DIR@
 INIT_SCRIPT=@INIT_SCRIPT@
 RC_LINK=@RC_LINK@
 
-TEST_PROGS = check_ttyname @CHECK_NOEXEC@
+TEST_PROGS = check_net_ifs @CHECK_NOEXEC@ check_ttyname
 TEST_LIBS = @LIBS@ $(LT_LIBS)
 TEST_LDFLAGS = @LDFLAGS@
 
@@ -135,6 +135,8 @@ POBJS = $(IOBJS:.i=.plog)
 
 SESH_OBJS = copy_file.o edit_open.o exec_common.o sesh.o
 
+CHECK_NET_IFS_OBJS = check_net_ifs.o net_ifs.o
+
 CHECK_NOEXEC_OBJS = check_noexec.o exec_common.o
 
 CHECK_TTYNAME_OBJS = check_ttyname.o ttyname.o
@@ -186,6 +188,9 @@ sudo_noexec.la: libsudo_noexec.la
 sesh: $(SESH_OBJS) $(LT_LIBS)
 	$(LIBTOOL) $(LTFLAGS) --mode=link $(CC) -o $@ $(SESH_OBJS) $(LDFLAGS) $(ASAN_LDFLAGS) $(PIE_LDFLAGS) $(SSP_LDFLAGS) $(LIBS)
 
+check_net_ifs: $(CHECK_NET_IFS_OBJS) $(top_builddir)/lib/util/libsudo_util.la
+	$(LIBTOOL) $(LTFLAGS) --mode=link $(CC) -o $@ $(CHECK_NET_IFS_OBJS) $(TEST_LDFLAGS) $(ASAN_LDFLAGS) $(PIE_LDFLAGS) $(SSP_LDFLAGS) $(TEST_LIBS)
+
 check_noexec: $(CHECK_NOEXEC_OBJS) $(top_builddir)/lib/util/libsudo_util.la sudo_noexec.la
 	$(LIBTOOL) $(LTFLAGS) --mode=link $(CC) -o $@ $(CHECK_NOEXEC_OBJS) $(TEST_LDFLAGS) $(ASAN_LDFLAGS) $(PIE_LDFLAGS) $(SSP_LDFLAGS) $(TEST_LIBS)
 
@@ -279,10 +284,11 @@ check: $(TEST_PROGS) check-fuzzer
 	    unset LANG || LANG=; \
 	    MALLOC_OPTIONS=S; export MALLOC_OPTIONS; \
 	    MALLOC_CONF="abort:true,junk:true"; export MALLOC_CONF; \
-	    ./check_ttyname; \
+	    ./check_net_ifs; \
 	    if test X"@CHECK_NOEXEC@" != X""; then \
 		./check_noexec .libs/$(noexecfile); \
 	    fi; \
+	    ./check_ttyname; \
 	fi
 
 clean:
@@ -310,6 +316,20 @@ sudo_noexec.lo: $(srcdir)/sudo_noexec.c $(incdir)/sudo_compat.h \
 	$(LIBTOOL) $(LTFLAGS) --mode=compile $(CC) -c $(CPPFLAGS) $(CFLAGS) $(PIE_CFLAGS) $(SSP_CFLAGS) $(srcdir)/sudo_noexec.c
 
 # Autogenerated dependencies, do not modify
+check_net_ifs.o: $(srcdir)/regress/net_ifs/check_net_ifs.c \
+                 $(incdir)/compat/stdbool.h $(incdir)/sudo_compat.h \
+                 $(incdir)/sudo_debug.h $(incdir)/sudo_fatal.h \
+                 $(incdir)/sudo_plugin.h $(incdir)/sudo_queue.h \
+                 $(incdir)/sudo_util.h $(top_builddir)/config.h
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $(ASAN_CFLAGS) $(PIE_CFLAGS) $(SSP_CFLAGS) $(srcdir)/regress/net_ifs/check_net_ifs.c
+check_net_ifs.i: $(srcdir)/regress/net_ifs/check_net_ifs.c \
+                 $(incdir)/compat/stdbool.h $(incdir)/sudo_compat.h \
+                 $(incdir)/sudo_debug.h $(incdir)/sudo_fatal.h \
+                 $(incdir)/sudo_plugin.h $(incdir)/sudo_queue.h \
+                 $(incdir)/sudo_util.h $(top_builddir)/config.h
+	$(CC) -E -o $@ $(CPPFLAGS) $<
+check_net_ifs.plog: check_net_ifs.i
+	rm -f $@; pvs-studio --cfg $(PVS_CFG) --sourcetree-root $(top_srcdir) --skip-cl-exe yes --source-file $(srcdir)/regress/net_ifs/check_net_ifs.c --i-file $< --output-file $@
 check_noexec.o: $(srcdir)/regress/noexec/check_noexec.c \
                 $(incdir)/compat/stdbool.h $(incdir)/sudo_compat.h \
                 $(incdir)/sudo_fatal.h $(incdir)/sudo_plugin.h \

src/regress/net_ifs/check_net_ifs.c

@@ -0,0 +1,62 @@
+/*
+ * 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 <sys/types.h>
+#include <sys/stat.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <limits.h>
+#include <errno.h>
+
+#include "sudo_compat.h"
+#include "sudo_fatal.h"
+#include "sudo_util.h"
+
+sudo_dso_public int main(int argc, char *argv[]);
+
+extern int get_net_ifs(char **addrinfo);
+
+int
+main(int argc, char *argv[])
+{
+    char *interfaces;
+    int ninterfaces;
+
+    initprogname(argc > 0 ? argv[0] : "check_net_ifs");
+
+    ninterfaces = get_net_ifs(&interfaces);
+    switch (ninterfaces) {
+    case -1:
+	sudo_warn_nodebug("unable to get network interfaces");
+	return 1;
+    case 0:
+	/* no interfaces or STUB_LOAD_INTERFACES defined. */
+	sudo_warnx_nodebug("OK: (0 interfaces)");
+	break;
+    default:
+	sudo_warnx_nodebug("OK: (%d interface%s, %s)", ninterfaces,
+	    ninterfaces > 1 ? "s" : "", interfaces);
+	break;
+    }
+
+    return 0;
+}