generators: be more careful when writing unit settings that support specifier expansion

[thirdparty/systemd.git] / src / cryptsetup / cryptsetup-generator.c

diff --git a/src/cryptsetup/cryptsetup-generator.c b/src/cryptsetup/cryptsetup-generator.c
index 613b018ce6e630ce9a4358dc9826ed5376f3b4d1..e2dc96bdb7e8499ed872684c15b7b5589c1a3c29 100644 (file)
--- a/src/cryptsetup/cryptsetup-generator.c
+++ b/src/cryptsetup/cryptsetup-generator.c
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
 /***
   This file is part of systemd.
 
@@ -31,6 +32,7 @@
 #include "parse-util.h"
 #include "path-util.h"
 #include "proc-cmdline.h"
+#include "specifier.h"
 #include "string-util.h"
 #include "strv.h"
 #include "unit-name.h"
@@ -59,10 +61,10 @@ static int create_disk(
                 const char *options) {
 
         _cleanup_free_ char *p = NULL, *n = NULL, *d = NULL, *u = NULL, *e = NULL,
-                *filtered = NULL;
+                *filtered = NULL, *u_escaped = NULL, *password_escaped = NULL, *filtered_escaped = NULL, *name_escaped = NULL;
         _cleanup_fclose_ FILE *f = NULL;
         const char *dmname;
-        bool noauto, nofail, tmp, swap;
+        bool noauto, nofail, tmp, swap, netdev;
         int r;
 
         assert(name);
@@ -72,12 +74,17 @@ static int create_disk(
         nofail = fstab_test_yes_no_option(options, "nofail\0" "fail\0");
         tmp = fstab_test_option(options, "tmp\0");
         swap = fstab_test_option(options, "swap\0");
+        netdev = fstab_test_option(options, "_netdev\0");
 
         if (tmp && swap) {
                 log_error("Device '%s' cannot be both 'tmp' and 'swap'. Ignoring.", name);
                 return -EINVAL;
         }
 
+        name_escaped = specifier_escape(name);
+        if (!name_escaped)
+                return log_oom();
+
         e = unit_name_escape(name);
         if (!e)
                 return log_oom();
@@ -94,28 +101,38 @@ static int create_disk(
         if (!u)
                 return log_oom();
 
+        u_escaped = specifier_escape(u);
+        if (!u_escaped)
+                return log_oom();
+
         r = unit_name_from_path(u, ".device", &d);
         if (r < 0)
                 return log_error_errno(r, "Failed to generate unit name: %m");
 
+        password_escaped = specifier_escape(password);
+        if (!password_escaped)
+                return log_oom();
+
         f = fopen(p, "wxe");
         if (!f)
                 return log_error_errno(errno, "Failed to create unit file %s: %m", p);
 
-        fputs_unlocked("# Automatically generated by systemd-cryptsetup-generator\n\n"
-                       "[Unit]\n"
-                       "Description=Cryptography Setup for %I\n"
-                       "Documentation=man:crypttab(5) man:systemd-cryptsetup-generator(8) man:systemd-cryptsetup@.service(8)\n"
-                       "SourcePath=/etc/crypttab\n"
-                       "DefaultDependencies=no\n"
-                       "Conflicts=umount.target\n"
-                       "IgnoreOnIsolate=true\n"
-                       "After=cryptsetup-pre.target\n",
-                       f);
+        fprintf(f,
+                "# Automatically generated by systemd-cryptsetup-generator\n\n"
+                "[Unit]\n"
+                "Description=Cryptography Setup for %%I\n"
+                "Documentation=man:crypttab(5) man:systemd-cryptsetup-generator(8) man:systemd-cryptsetup@.service(8)\n"
+                "SourcePath=/etc/crypttab\n"
+                "DefaultDependencies=no\n"
+                "Conflicts=umount.target\n"
+                "IgnoreOnIsolate=true\n"
+                "After=%s\n",
+                netdev ? "remote-fs-pre.target" : "cryptsetup-pre.target");
 
         if (!nofail)
                 fprintf(f,
-                        "Before=cryptsetup.target\n");
+                        "Before=%s\n",
+                        netdev ? "remote-cryptsetup.target" : "cryptsetup.target");
 
         if (password) {
                 if (STR_IN_SET(password, "/dev/urandom", "/dev/random", "/dev/hw_random"))
@@ -138,7 +155,7 @@ static int create_disk(
 
                                         fprintf(f, "After=%1$s\nRequires=%1$s\n", dd);
                                 } else
-                                        fprintf(f, "RequiresMountsFor=%s\n", password);
+                                        fprintf(f, "RequiresMountsFor=%s\n", password_escaped);
                         }
                 }
         }
@@ -156,31 +173,37 @@ static int create_disk(
         } else
                 fprintf(f,
                         "RequiresMountsFor=%s\n",
-                        u);
+                        u_escaped);
+
 
         r = generator_write_timeouts(arg_dest, device, name, options, &filtered);
         if (r < 0)
                 return r;
 
+        filtered_escaped = specifier_escape(filtered);
+        if (!filtered_escaped)
+                return log_oom();
+
         fprintf(f,
                 "\n[Service]\n"
                 "Type=oneshot\n"
                 "RemainAfterExit=yes\n"
                 "TimeoutSec=0\n" /* the binary handles timeouts anyway */
+                "KeyringMode=shared\n" /* make sure we can share cached keys among instances */
                 "ExecStart=" SYSTEMD_CRYPTSETUP_PATH " attach '%s' '%s' '%s' '%s'\n"
                 "ExecStop=" SYSTEMD_CRYPTSETUP_PATH " detach '%s'\n",
-                name, u, strempty(password), strempty(filtered),
-                name);
+                name_escaped, u_escaped, strempty(password_escaped), strempty(filtered_escaped),
+                name_escaped);
 
         if (tmp)
                 fprintf(f,
                         "ExecStartPost=/sbin/mke2fs '/dev/mapper/%s'\n",
-                        name);
+                        name_escaped);
 
         if (swap)
                 fprintf(f,
                         "ExecStartPost=/sbin/mkswap '/dev/mapper/%s'\n",
-                        name);
+                        name_escaped);
 
         r = fflush_and_check(f);
         if (r < 0)
@@ -191,7 +214,8 @@ static int create_disk(
                 if (r < 0)
                         return r;
 
-                r = generator_add_symlink(arg_dest, "cryptsetup.target",
+                r = generator_add_symlink(arg_dest,
+                                          netdev ? "remote-cryptsetup.target" : "cryptsetup.target",
                                           nofail ? "wants" : "requires", n);
                 if (r < 0)
                         return r;
@@ -213,18 +237,12 @@ static int create_disk(
         return 0;
 }
 
-static void free_arg_disks(void) {
-        crypto_device *d;
-
-        while ((d = hashmap_steal_first(arg_disks))) {
-                free(d->uuid);
-                free(d->keyfile);
-                free(d->name);
-                free(d->options);
-                free(d);
-        }
-
-        hashmap_free(arg_disks);
+static void crypt_device_free(crypto_device *d) {
+        free(d->uuid);
+        free(d->keyfile);
+        free(d->name);
+        free(d->options);
+        free(d);
 }
 
 static crypto_device *get_crypto_device(const char *uuid) {
@@ -331,9 +349,7 @@ static int parse_proc_cmdline_item(const char *key, const char *value, void *dat
 
                         d->create = arg_whitelist = true;
 
-                        free(d->name);
-                        d->name = uuid_value;
-                        uuid_value = NULL;
+                        free_and_replace(d->name, uuid_value);
                 } else
                         log_warning("Failed to parse luks name switch %s. Ignoring.", value);
         }
@@ -373,7 +389,7 @@ static int add_crypttab_devices(void) {
                 crypttab_line++;
 
                 l = strstrip(line);
-                if (*l == '#' || *l == 0)
+                if (IN_SET(*l, 0, '#'))
                         continue;
 
                 k = sscanf(l, "%ms %ms %ms %ms", &name, &device, &keyfile, &options);
@@ -488,7 +504,7 @@ int main(int argc, char *argv[]) {
         r = 0;
 
 finish:
-        free_arg_disks();
+        hashmap_free_with_destructor(arg_disks, crypt_device_free);
         free(arg_default_options);
         free(arg_default_keyfile);