Do not depend in test on loop code from library sources.

This patch duplicates part of the code because following
switch to non-recursive automake is not easily fixable without this change.

(Automake cannot use top_srcdir anymore in this context.)

tests/Makefile.am

@@ -64,13 +64,13 @@ clean-local:
 differ_SOURCES = differ.c
 differ_CFLAGS = $(AM_CFLAGS) -Wall -O2
 
-api_test_SOURCES = api-test.c api_test.h test_utils.c $(top_srcdir)/lib/utils_loop.c
+api_test_SOURCES = api-test.c api_test.h test_utils.c
 api_test_LDADD = ../lib/libcryptsetup.la
 api_test_LDFLAGS = $(AM_LDFLAGS) -static
 api_test_CFLAGS = -g -Wall -O0 $(AM_CFLAGS) -I$(top_srcdir)/lib/ -I$(top_srcdir)/lib/luks1
 api_test_CPPFLAGS = $(AM_CPPFLAGS) -include config.h
 
-api_test_2_SOURCES = api-test-2.c api_test.h test_utils.c $(top_srcdir)/lib/utils_loop.c
+api_test_2_SOURCES = api-test-2.c api_test.h test_utils.c
 api_test_2_LDADD = ../lib/libcryptsetup.la
 api_test_2_LDFLAGS = $(AM_LDFLAGS) -static
 api_test_2_CFLAGS = -g -Wall -O0 $(AM_CFLAGS) -I$(top_srcdir)/lib/ -I$(top_srcdir)/lib/luks1

tests/api-test-2.c

@@ -42,7 +42,6 @@ typedef int32_t key_serial_t;
 #include "api_test.h"
 #include "luks.h"
 #include "libcryptsetup.h"
-#include "utils_loop.h"
 
 #define DMDIR "/dev/mapper/"
 
@@ -235,26 +234,26 @@ static void _cleanup(void)
 
 	_cleanup_dmdevices();
 
-	if (crypt_loop_device(THE_LOOP_DEV))
-		crypt_loop_detach(THE_LOOP_DEV);
+	if (loop_device(THE_LOOP_DEV))
+		loop_detach(THE_LOOP_DEV);
 
-	if (crypt_loop_device(DEVICE_1))
-		crypt_loop_detach(DEVICE_1);
+	if (loop_device(DEVICE_1))
+		loop_detach(DEVICE_1);
 
-	if (crypt_loop_device(DEVICE_2))
-		crypt_loop_detach(DEVICE_2);
+	if (loop_device(DEVICE_2))
+		loop_detach(DEVICE_2);
 
-	if (crypt_loop_device(DEVICE_3))
-		crypt_loop_detach(DEVICE_3);
+	if (loop_device(DEVICE_3))
+		loop_detach(DEVICE_3);
 
-	if (crypt_loop_device(DEVICE_4))
-		crypt_loop_detach(DEVICE_4);
+	if (loop_device(DEVICE_4))
+		loop_detach(DEVICE_4);
 
-	if (crypt_loop_device(DEVICE_5))
-		crypt_loop_detach(DEVICE_5);
+	if (loop_device(DEVICE_5))
+		loop_detach(DEVICE_5);
 
-	if (crypt_loop_device(DEVICE_6))
-		crypt_loop_detach(DEVICE_6);
+	if (loop_device(DEVICE_6))
+		loop_detach(DEVICE_6);
 
 	_system("rm -f " IMAGE_EMPTY, 0);
 	_system("rm -f " IMAGE1, 0);
@@ -297,7 +296,7 @@ static int _setup(void)
 	if (_system(cmd, 1))
 		return 1;
 
-	fd = crypt_loop_attach(&THE_LOOP_DEV, test_loop_file, 0, 0, &ro);
+	fd = loop_attach(&THE_LOOP_DEV, test_loop_file, 0, 0, &ro);
 	close(fd);
 
 	tmp_file_1 = strdup(THE_LFILE_TEMPLATE);
@@ -315,23 +314,23 @@ static int _setup(void)
 	_system("dmsetup create " DEVICE_ERROR_name " --table \"0 10000 error\"", 1);
 
 	_system(" [ ! -e " IMAGE1 " ] && xz -dk " IMAGE1 ".xz", 1);
-	fd = crypt_loop_attach(&DEVICE_1, IMAGE1, 0, 0, &ro);
+	fd = loop_attach(&DEVICE_1, IMAGE1, 0, 0, &ro);
 	close(fd);
 
 	_system("dd if=/dev/zero of=" IMAGE_EMPTY " bs=1M count=32 2>/dev/null", 1);
-	fd = crypt_loop_attach(&DEVICE_2, IMAGE_EMPTY, 0, 0, &ro);
+	fd = loop_attach(&DEVICE_2, IMAGE_EMPTY, 0, 0, &ro);
 	close(fd);
 
 	_system(" [ ! -e " VALID_LUKS2_HEADER " ] && xz -dk " VALID_LUKS2_HEADER ".xz", 1);
-	fd = crypt_loop_attach(&DEVICE_4, VALID_LUKS2_HEADER, 0, 0, &ro);
+	fd = loop_attach(&DEVICE_4, VALID_LUKS2_HEADER, 0, 0, &ro);
 	close(fd);
 
 	_system(" [ ! -e " REQS_LUKS2_HEADER " ] && xz -dk " REQS_LUKS2_HEADER ".xz", 1);
-	fd = crypt_loop_attach(&DEVICE_5, REQS_LUKS2_HEADER, 0, 0, &ro);
+	fd = loop_attach(&DEVICE_5, REQS_LUKS2_HEADER, 0, 0, &ro);
 	close(fd);
 
 	_system(" [ ! -e " NO_REQS_LUKS2_HEADER " ] && xz -dk " NO_REQS_LUKS2_HEADER ".xz", 1);
-	fd = crypt_loop_attach(&DEVICE_6, NO_REQS_LUKS2_HEADER, 0, 0, &ro);
+	fd = loop_attach(&DEVICE_6, NO_REQS_LUKS2_HEADER, 0, 0, &ro);
 	close(fd);
 
 	_system(" [ ! -d " CONV_DIR " ] && tar xJf " CONV_DIR ".tar.xz", 1);
@@ -1108,7 +1107,7 @@ static void Luks2HeaderBackup(void)
 	crypt_free(cd);
 
 	// exercise luksOpen using backup header on block device
-	fd = crypt_loop_attach(&DEVICE_3, BACKUP_FILE, 0, 0, &ro);
+	fd = loop_attach(&DEVICE_3, BACKUP_FILE, 0, 0, &ro);
 	close(fd);
 	OK_(fd < 0);
 	OK_(crypt_init(&cd, DEVICE_3));

tests/api-test.c

@@ -33,7 +33,6 @@
 #include "api_test.h"
 #include "luks.h"
 #include "libcryptsetup.h"
-#include "utils_loop.h"
 
 #define DMDIR "/dev/mapper/"
 
@@ -185,17 +184,17 @@ static void _cleanup(void)
 
 	_cleanup_dmdevices();
 
-	if (crypt_loop_device(THE_LOOP_DEV))
-		crypt_loop_detach(THE_LOOP_DEV);
+	if (loop_device(THE_LOOP_DEV))
+		loop_detach(THE_LOOP_DEV);
 
-	if (crypt_loop_device(DEVICE_1))
-		crypt_loop_detach(DEVICE_1);
+	if (loop_device(DEVICE_1))
+		loop_detach(DEVICE_1);
 
-	if (crypt_loop_device(DEVICE_2))
-		crypt_loop_detach(DEVICE_2);
+	if (loop_device(DEVICE_2))
+		loop_detach(DEVICE_2);
 
-	if (crypt_loop_device(DEVICE_3))
-		crypt_loop_detach(DEVICE_3);
+	if (loop_device(DEVICE_3))
+		loop_detach(DEVICE_3);
 
 	_system("rm -f " IMAGE_EMPTY, 0);
 	_system("rm -f " IMAGE1, 0);
@@ -237,7 +236,7 @@ static int _setup(void)
 	if (_system(cmd, 1))
 		return 1;
 
-	fd = crypt_loop_attach(&THE_LOOP_DEV, test_loop_file, 0, 0, &ro);
+	fd = loop_attach(&THE_LOOP_DEV, test_loop_file, 0, 0, &ro);
 	close(fd);
 
 	tmp_file_1 = strdup(THE_LFILE_TEMPLATE);
@@ -255,11 +254,11 @@ static int _setup(void)
 	_system("dmsetup create " DEVICE_ERROR_name " --table \"0 10000 error\"", 1);
 
 	_system(" [ ! -e " IMAGE1 " ] && bzip2 -dk " IMAGE1 ".bz2", 1);
-	fd = crypt_loop_attach(&DEVICE_1, IMAGE1, 0, 0, &ro);
+	fd = loop_attach(&DEVICE_1, IMAGE1, 0, 0, &ro);
 	close(fd);
 
 	_system("dd if=/dev/zero of=" IMAGE_EMPTY " bs=1M count=4 2>/dev/null", 1);
-	fd = crypt_loop_attach(&DEVICE_2, IMAGE_EMPTY, 0, 0, &ro);
+	fd = loop_attach(&DEVICE_2, IMAGE_EMPTY, 0, 0, &ro);
 	close(fd);
 
 	/* Keymaterial offset is less than 8 sectors */
@@ -1227,7 +1226,7 @@ static void LuksHeaderBackup(void)
 	crypt_free(cd);
 
 	// exercise luksOpen using backup header on block device
-	fd = crypt_loop_attach(&DEVICE_3, BACKUP_FILE, 0, 0, &ro);
+	fd = loop_attach(&DEVICE_3, BACKUP_FILE, 0, 0, &ro);
 	close(fd);
 	OK_(fd < 0);
 	OK_(crypt_init(&cd, DEVICE_3));

tests/api_test.h

@@ -105,4 +105,10 @@ void xlog(const char *msg, const char *tst, const char *func, int line, const ch
 #define T_DM_INTEGRITY_SUPPORTED (1 << 12) /* dm-integrity target supported */
 //FIXME add T_DM_SECTOR_SIZE once we have version
 
+/* loop helpers */
+int loop_device(const char *loop);
+int loop_attach(char **loop, const char *file, int offset,
+		      int autoclear, int *readonly);
+int loop_detach(const char *loop);
+
 #endif

tests/test_utils.c

@@ -29,6 +29,7 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <linux/loop.h>
 
 #include "api_test.h"
 #include "libcryptsetup.h"
@@ -402,3 +403,170 @@ int t_dm_crypt_keyring_support(void)
 {
 	return t_dm_crypt_flags & T_DM_KERNEL_KEYRING_SUPPORTED;
 }
+
+/* loop helpers */
+
+#define LOOP_DEV_MAJOR 7
+
+#ifndef LO_FLAGS_AUTOCLEAR
+#define LO_FLAGS_AUTOCLEAR 4
+#endif
+
+#ifndef LOOP_CTL_GET_FREE
+#define LOOP_CTL_GET_FREE 0x4C82
+#endif
+
+#ifndef LOOP_SET_CAPACITY
+#define LOOP_SET_CAPACITY 0x4C07
+#endif
+
+int loop_device(const char *loop)
+{
+	struct stat st;
+
+	if (!loop)
+		return 0;
+
+	if (stat(loop, &st) || !S_ISBLK(st.st_mode) ||
+	    major(st.st_rdev) != LOOP_DEV_MAJOR)
+		return 0;
+
+	return 1;
+}
+
+static char *crypt_loop_get_device_old(void)
+{
+	char dev[20];
+	int i, loop_fd;
+	struct loop_info64 lo64 = {0};
+
+	for (i = 0; i < 256; i++) {
+		sprintf(dev, "/dev/loop%d", i);
+
+		loop_fd = open(dev, O_RDONLY);
+		if (loop_fd < 0)
+			return NULL;
+
+		if (ioctl(loop_fd, LOOP_GET_STATUS64, &lo64) &&
+		    errno == ENXIO) {
+			close(loop_fd);
+			return strdup(dev);
+		}
+		close(loop_fd);
+	}
+
+	return NULL;
+}
+
+static char *crypt_loop_get_device(void)
+{
+	char dev[64];
+	int i, loop_fd;
+	struct stat st;
+
+	loop_fd = open("/dev/loop-control", O_RDONLY);
+	if (loop_fd < 0)
+		return crypt_loop_get_device_old();
+
+	i = ioctl(loop_fd, LOOP_CTL_GET_FREE);
+	if (i < 0) {
+		close(loop_fd);
+		return NULL;
+	}
+	close(loop_fd);
+
+	if (sprintf(dev, "/dev/loop%d", i) < 0)
+		return NULL;
+
+	if (stat(dev, &st) || !S_ISBLK(st.st_mode))
+		return NULL;
+
+	return strdup(dev);
+}
+
+int loop_attach(char **loop, const char *file, int offset,
+		      int autoclear, int *readonly)
+{
+	struct loop_info64 lo64 = {0};
+	char *lo_file_name;
+	int loop_fd = -1, file_fd = -1, r = 1;
+
+	*loop = NULL;
+
+	file_fd = open(file, (*readonly ? O_RDONLY : O_RDWR) | O_EXCL);
+	if (file_fd < 0 && (errno == EROFS || errno == EACCES) && !*readonly) {
+		*readonly = 1;
+		file_fd = open(file, O_RDONLY | O_EXCL);
+	}
+	if (file_fd < 0)
+		goto out;
+
+	while (loop_fd < 0)  {
+		*loop = crypt_loop_get_device();
+		if (!*loop)
+			goto out;
+
+		loop_fd = open(*loop, *readonly ? O_RDONLY : O_RDWR);
+		if (loop_fd < 0)
+			goto out;
+
+		if (ioctl(loop_fd, LOOP_SET_FD, file_fd) < 0) {
+			if (errno != EBUSY)
+				goto out;
+			free(*loop);
+			*loop = NULL;
+
+			close(loop_fd);
+			loop_fd = -1;
+		}
+	}
+
+	lo_file_name = (char*)lo64.lo_file_name;
+	lo_file_name[LO_NAME_SIZE-1] = '\0';
+	strncpy(lo_file_name, file, LO_NAME_SIZE-1);
+	lo64.lo_offset = offset;
+	if (autoclear)
+		lo64.lo_flags |= LO_FLAGS_AUTOCLEAR;
+
+	if (ioctl(loop_fd, LOOP_SET_STATUS64, &lo64) < 0) {
+		(void)ioctl(loop_fd, LOOP_CLR_FD, 0);
+		goto out;
+	}
+
+	/* Verify that autoclear is really set */
+	if (autoclear) {
+		memset(&lo64, 0, sizeof(lo64));
+		if (ioctl(loop_fd, LOOP_GET_STATUS64, &lo64) < 0 ||
+		   !(lo64.lo_flags & LO_FLAGS_AUTOCLEAR)) {
+		(void)ioctl(loop_fd, LOOP_CLR_FD, 0);
+			goto out;
+		}
+	}
+
+	r = 0;
+out:
+	if (r && loop_fd >= 0)
+		close(loop_fd);
+	if (file_fd >= 0)
+		close(file_fd);
+	if (r && *loop) {
+		free(*loop);
+		*loop = NULL;
+	}
+	return r ? -1 : loop_fd;
+}
+
+int loop_detach(const char *loop)
+{
+	int loop_fd = -1, r = 1;
+
+	loop_fd = open(loop, O_RDONLY);
+	if (loop_fd < 0)
+                return 1;
+
+	if (!ioctl(loop_fd, LOOP_CLR_FD, 0))
+		r = 0;
+
+	close(loop_fd);
+	return r;
+}