boot: remove random-seed-mode

Now that the random seed is used on virtualized systems, there's no
point in having a random-seed-mode toggle switch. Let's just always
require it now, with the existing logic already being there to allow not
having it if EFI itself has an RNG. In other words, the logic for this
can now be automatic.

diff --git a/docs/RANDOM_SEEDS.md b/docs/RANDOM_SEEDS.md
index a1134d6417ea0a104ff0679304f39ff0ae1eb257..4cb2bb9cfa5f74fb96ae8325d9c8dcfedac8a2df 100644 (file)
--- a/docs/RANDOM_SEEDS.md
+++ b/docs/RANDOM_SEEDS.md
@@ -232,14 +232,6 @@ boot, in order to ensure the entropy pool is filled up quickly.
    too), which should be safe even with FAT file system drivers built into
    low-quality EFI firmwares.
 
-   If the system token is not desired but this seeding mechanism still is, OS
-   builders that know that they are not going to replicate the built image on
-   multiple systems may opt to turn off the 'system token' concept by setting
-   `random-seed-mode always` in the ESP's
-   [`/loader/loader.conf`](https://www.freedesktop.org/software/systemd/man/loader.conf.html)
-   file. If done, `systemd-boot` will use the random seed file even if no
-   system token is found in EFI variables.
-
 4. A kernel command line option `systemd.random_seed=` may be used to pass in a
    base64 encoded seed to initialize the kernel's entropy pool from during
    early service manager initialization. This option is only safe in testing

diff --git a/man/loader.conf.xml b/man/loader.conf.xml
index cf84119df0c4173cff1da9062877e7f04c0314e9..245f4c4536600384feaf2811810dde36bb0d64b5 100644 (file)
--- a/man/loader.conf.xml
+++ b/man/loader.conf.xml
@@ -309,25 +309,6 @@ sign-efi-sig-list -c KEK.crt -k KEK.key db db.esl db.auth
         encrypted drive to change. If PCR 4 is not measured, this setting can be disabled to speed
         up booting into Windows.</para></listitem>
       </varlistentry>
-
-      <varlistentry>
-        <term>random-seed-mode</term>
-
-        <listitem><para>Takes one of <literal>off</literal>, <literal>with-system-token</literal> and
-        <literal>always</literal>. If <literal>off</literal> no random seed data is read off the ESP, nor
-        passed to the OS. If <literal>with-system-token</literal> (the default)
-        <command>systemd-boot</command> will read a random seed from the ESP (from the file
-        <filename>/loader/random-seed</filename>) only if the <varname>LoaderSystemToken</varname> EFI
-        variable is set, and then derive the random seed to pass to the OS from the combination. If
-        <literal>always</literal> the boot loader will do so even if <varname>LoaderSystemToken</varname> is
-        not set. This mode is useful in environments where protection against OS image reuse is not a
-        concern, and the random seed shall be used even with no further setup in place. Use <command>bootctl
-        random-seed</command> to initialize both the random seed file in the ESP and the system token EFI
-        variable.</para>
-
-        <para>See <ulink url="https://systemd.io/RANDOM_SEEDS">Random Seeds</ulink> for further
-        information.</para></listitem>
-      </varlistentry>
     </variablelist>
   </refsect1>
 

diff --git a/src/boot/efi/boot.c b/src/boot/efi/boot.c
index ac9d11aaccada215fea2ae5f7debb0260749dcfb..caa2a69a6f48836c39b09bb5e333161381b19d2e 100644 (file)
--- a/src/boot/efi/boot.c
+++ b/src/boot/efi/boot.c
@@ -97,7 +97,6 @@ typedef struct {
         bool beep;
         int64_t console_mode;
         int64_t console_mode_efivar;
-        RandomSeedMode random_seed_mode;
 } Config;
 
 /* These values have been chosen so that the transitions the user sees could
@@ -529,7 +528,6 @@ static void print_status(Config *config, char16_t *loaded_image_path) {
           ps_bool(L"         auto-firmware: %s\n", config->auto_firmware);
           ps_bool(L"                  beep: %s\n", config->beep);
           ps_bool(L"  reboot-for-bitlocker: %s\n", config->reboot_for_bitlocker);
-        ps_string(L"      random-seed-mode: %s\n", random_seed_modes_table[config->random_seed_mode]);
 
         switch (config->secure_boot_enroll) {
         case ENROLL_OFF:
@@ -1273,27 +1271,6 @@ static void config_defaults_load_from_file(Config *config, char *content) {
                         }
                         continue;
                 }
-
-                if (streq8(key, "random-seed-mode")) {
-                        if (streq8(value, "off"))
-                                config->random_seed_mode = RANDOM_SEED_OFF;
-                        else if (streq8(value, "with-system-token"))
-                                config->random_seed_mode = RANDOM_SEED_WITH_SYSTEM_TOKEN;
-                        else if (streq8(value, "always"))
-                                config->random_seed_mode = RANDOM_SEED_ALWAYS;
-                        else {
-                                bool on;
-
-                                err = parse_boolean(value, &on);
-                                if (err != EFI_SUCCESS) {
-                                        log_error_stall(L"Error parsing 'random-seed-mode' config option: %a", value);
-                                        continue;
-                                }
-
-                                config->random_seed_mode = on ? RANDOM_SEED_ALWAYS : RANDOM_SEED_OFF;
-                        }
-                        continue;
-                }
         }
 }
 
@@ -1584,7 +1561,6 @@ static void config_load_defaults(Config *config, EFI_FILE *root_dir) {
                 .auto_firmware = true,
                 .reboot_for_bitlocker = false,
                 .secure_boot_enroll = ENROLL_MANUAL,
-                .random_seed_mode = RANDOM_SEED_WITH_SYSTEM_TOKEN,
                 .idx_default_efivar = IDX_INVALID,
                 .console_mode = CONSOLE_MODE_KEEP,
                 .console_mode_efivar = CONSOLE_MODE_KEEP,
@@ -2743,7 +2719,7 @@ EFI_STATUS efi_main(EFI_HANDLE image, EFI_SYSTEM_TABLE *sys_table) {
                 save_selected_entry(&config, entry);
 
                 /* Optionally, read a random seed off the ESP and pass it to the OS */
-                (void) process_random_seed(root_dir, config.random_seed_mode);
+                (void) process_random_seed(root_dir);
 
                 err = image_start(image, entry);
                 if (err != EFI_SUCCESS)

diff --git a/src/boot/efi/random-seed.c b/src/boot/efi/random-seed.c
index e6a317860d8bacd819933a19d647a11524749d23..22ba1c5a30e93f16bd48072eab3c06e9f047c2dc 100644 (file)
--- a/src/boot/efi/random-seed.c
+++ b/src/boot/efi/random-seed.c
@@ -116,7 +116,7 @@ static void validate_sha256(void) {
 #endif
 }
 
-EFI_STATUS process_random_seed(EFI_FILE *root_dir, RandomSeedMode mode) {
+EFI_STATUS process_random_seed(EFI_FILE *root_dir) {
         _cleanup_erase_ uint8_t random_bytes[DESIRED_SEED_SIZE], hash_key[HASH_VALUE_SIZE];
         _cleanup_free_ struct linux_efi_random_seed *new_seed_table = NULL;
         struct linux_efi_random_seed *previous_seed_table = NULL;
@@ -135,9 +135,6 @@ EFI_STATUS process_random_seed(EFI_FILE *root_dir, RandomSeedMode mode) {
 
         validate_sha256();
 
-        if (mode == RANDOM_SEED_OFF)
-                return EFI_NOT_FOUND;
-
         /* hash = LABEL || sizeof(input1) || input1 || ... || sizeof(inputN) || inputN */
         sha256_init_ctx(&hash);
 
@@ -188,7 +185,7 @@ EFI_STATUS process_random_seed(EFI_FILE *root_dir, RandomSeedMode mode) {
          * system, even when disk images are duplicated or swapped out. */
         size = 0;
         err = acquire_system_token(&system_token, &size);
-        if (mode != RANDOM_SEED_ALWAYS && (err != EFI_SUCCESS || size < DESIRED_SEED_SIZE) && !seeded_by_efi)
+        if ((err != EFI_SUCCESS || size < DESIRED_SEED_SIZE) && !seeded_by_efi)
                 return err;
         sha256_process_bytes(&size, sizeof(size), &hash);
         if (system_token) {

diff --git a/src/boot/efi/random-seed.h b/src/boot/efi/random-seed.h
index 6aa1cc52885b7dceea4d79c06f445574a14c599e..40aaf85860f508492d3a4b9bd5740236813bf33e 100644 (file)
--- a/src/boot/efi/random-seed.h
+++ b/src/boot/efi/random-seed.h
@@ -2,21 +2,5 @@
 #pragma once
 
 #include <efi.h>
-#include <errno.h>
-#include <uchar.h>
 
-typedef enum RandomSeedMode {
-        RANDOM_SEED_OFF,
-        RANDOM_SEED_WITH_SYSTEM_TOKEN,
-        RANDOM_SEED_ALWAYS,
-        _RANDOM_SEED_MODE_MAX,
-        _RANDOM_SEED_MODE_INVALID = -EINVAL,
-} RandomSeedMode;
-
-static const char16_t * const random_seed_modes_table[_RANDOM_SEED_MODE_MAX] = {
-        [RANDOM_SEED_OFF]               = L"off",
-        [RANDOM_SEED_WITH_SYSTEM_TOKEN] = L"with-system-token",
-        [RANDOM_SEED_ALWAYS]            = L"always",
-};
-
-EFI_STATUS process_random_seed(EFI_FILE *root_dir, RandomSeedMode mode);
+EFI_STATUS process_random_seed(EFI_FILE *root_dir);

diff --git a/src/shared/bootspec.c b/src/shared/bootspec.c
index ff5cd9bc1fbe7cf16e7c5e8b9dba1b3e75add83d..3dec5439dd9174c36382beb02aea11e4ee928da7 100644 (file)
--- a/src/shared/bootspec.c
+++ b/src/shared/bootspec.c
@@ -419,7 +419,6 @@ void boot_config_free(BootConfig *config) {
         free(config->auto_entries);
         free(config->auto_firmware);
         free(config->console_mode);
-        free(config->random_seed_mode);
         free(config->beep);
 
         free(config->entry_oneshot);
@@ -486,7 +485,7 @@ int boot_loader_read_conf(BootConfig *config, FILE *file, const char *path) {
                 else if (streq(field, "console-mode"))
                         r = free_and_strdup(&config->console_mode, p);
                 else if (streq(field, "random-seed-mode"))
-                        r = free_and_strdup(&config->random_seed_mode, p);
+                        log_syntax(NULL, LOG_WARNING, path, line, 0, "'random-seed-mode' has been deprecated, ignoring.");
                 else if (streq(field, "beep"))
                         r = free_and_strdup(&config->beep, p);
                 else {

diff --git a/src/shared/bootspec.h b/src/shared/bootspec.h
index 7f5d496b95726cdefd6be2aa1e9ddaeb9bc6acd3..ac4d1890b09c90a93305eaef0232e78ce17fbbfe 100644 (file)
--- a/src/shared/bootspec.h
+++ b/src/shared/bootspec.h
@@ -57,7 +57,6 @@ typedef struct BootConfig {
         char *auto_entries;
         char *auto_firmware;
         char *console_mode;
-        char *random_seed_mode;
         char *beep;
 
         char *entry_oneshot;