From 9040e15cd3cba546b47aeae0ea133afa1a6ad292 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>

Date: Wed, 13 Nov 2019 10:32:30 +0100

Subject: [PATCH] cryptsetup-generator: guess whether the keyfile argument is

 two items or one

Fixes #13615.

See the inline comment for documentation.

(cherry picked from commit 32c6237a7c2e697d2fc4f3403319db16858fb8e3)

Related: #1763155

---

 src/cryptsetup/cryptsetup-generator.c | 45 ++++++++++++++++++---------

 1 file changed, 30 insertions(+), 15 deletions(-)

diff --git a/src/cryptsetup/cryptsetup-generator.c b/src/cryptsetup/cryptsetup-generator.c

index a09983b576..4117930925 100644

--- a/src/cryptsetup/cryptsetup-generator.c

+++ b/src/cryptsetup/cryptsetup-generator.c

@@ -54,17 +54,36 @@ static int split_keyspec(const char *keyspec, char **ret_keyfile, char **ret_key

         c = strrchr(keyspec, ':');

         if (c) {

-                keyfile = strndup(keyspec, c-keyspec);

-                keydev = strdup(c + 1);

-                if (!keyfile || !keydev)

+                /* The keydev part has to be either an absolute path to device node (/dev/something,

+                 * /dev/foo/something, or even possibly /dev/foo/something:part), or a fstab device

+                 * specification starting with LABEL= or similar. The keyfile part has the same syntax.

+                 *

+                 * Let's try to guess if the second part looks like a keydev specification, or just part of a

+                 * filename with a colon. fstab_node_to_udev_node() will convert the fstab device syntax to

+                 * an absolute path. If we didn't get an absolute path, assume that it is just part of the

+                 * first keyfile argument. */

+

+                keydev = fstab_node_to_udev_node(c + 1);

+                if (!keydev)

                         return log_oom();

-        } else {

+

+                if (path_is_absolute(keydev))

+                        keyfile = strndup(keyspec, c-keyspec);

+                else {

+                        log_debug("Keyspec argument contains a colon, but \"%s\" doesn't look like a device specification.\n"

+                                  "Assuming that \"%s\" is a single device specification.",

+                                  c + 1, keyspec);

+                        keydev = mfree(keydev);

+                        c = NULL;

+                }

+        }

+

+        if (!c)

                 /* No keydev specified */

                 keyfile = strdup(keyspec);

-                keydev = NULL;

-                if (!keyfile)

-                        return log_oom();

-        }

+

+        if (!keyfile)

+                return log_oom();

         *ret_keyfile = TAKE_PTR(keyfile);

         *ret_keydev = TAKE_PTR(keydev);

@@ -73,7 +92,7 @@ static int split_keyspec(const char *keyspec, char **ret_keyfile, char **ret_key

 }

 static int generate_keydev_mount(const char *name, const char *keydev, const char *keydev_timeout, bool canfail, char **unit, char **mount) {

-        _cleanup_free_ char *u = NULL, *what = NULL, *where = NULL, *name_escaped = NULL, *device_unit = NULL;

+        _cleanup_free_ char *u = NULL, *where = NULL, *name_escaped = NULL, *device_unit = NULL;

         _cleanup_fclose_ FILE *f = NULL;

         int r;

         usec_t timeout_us;

@@ -111,22 +130,18 @@ static int generate_keydev_mount(const char *name, const char *keydev, const cha

         if (r < 0)

                 return r;

-        what = fstab_node_to_udev_node(keydev);

-        if (!what)

-                return -ENOMEM;

-

         fprintf(f,

                 "[Unit]\n"

                 "DefaultDependencies=no\n\n"

                 "[Mount]\n"

                 "What=%s\n"

                 "Where=%s\n"

-                "Options=ro%s\n", what, where, canfail ? ",nofail" : "");

+                "Options=ro%s\n", keydev, where, canfail ? ",nofail" : "");

         if (keydev_timeout) {

                 r = parse_sec_fix_0(keydev_timeout, &timeout_us);

                 if (r >= 0) {

-                        r = unit_name_from_path(what, ".device", &device_unit);

+                        r = unit_name_from_path(keydev, ".device", &device_unit);

                         if (r < 0)

                                 return log_error_errno(r, "Failed to generate unit name: %m");