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systemd/SOURCES/0729-cryptsetup-do-not-asse...

76 lines
2.9 KiB

From 540f1d6b38dc6f2f72785ba7b44ad3cc65243982 Mon Sep 17 00:00:00 2001
From: Luca Boccassi <bluca@debian.org>
Date: Wed, 15 Feb 2023 00:44:01 +0000
Subject: [PATCH] cryptsetup: do not assert when unsealing token without salt
Salt was added in v253. We are not checking whether it was actually found
(non-zero size), so when an old tpm+pin enrollment is opened things go boom.
For good measure, check both the buffer and the size in both places.
Assertion 'saltlen > 0' failed at src/shared/tpm2-util.c:2490, function tpm2_util_pbkdf2_hmac_sha256(). Aborting.
(cherry picked from commit 504d0acf61c8472bc93c2a927e858074873b2eaf)
Resolves: RHEL-40119
---
src/cryptsetup/cryptsetup-tokens/luks2-tpm2.c | 3 ++-
src/cryptsetup/cryptsetup-tpm2.c | 4 +++-
src/shared/tpm2-util.c | 1 +
3 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/src/cryptsetup/cryptsetup-tokens/luks2-tpm2.c b/src/cryptsetup/cryptsetup-tokens/luks2-tpm2.c
index 630a2d8d3e..e353e947aa 100644
--- a/src/cryptsetup/cryptsetup-tokens/luks2-tpm2.c
+++ b/src/cryptsetup/cryptsetup-tokens/luks2-tpm2.c
@@ -40,6 +40,7 @@ int acquire_luks2_key(
_cleanup_(erase_and_freep) char *b64_salted_pin = NULL;
int r;
+ assert(salt || salt_size == 0);
assert(ret_decrypted_key);
assert(ret_decrypted_key_size);
@@ -60,7 +61,7 @@ int acquire_luks2_key(
if ((flags & TPM2_FLAGS_USE_PIN) && salt && !pin)
return -ENOANO;
- if (pin) {
+ if (pin && salt_size > 0) {
uint8_t salted_pin[SHA256_DIGEST_SIZE] = {};
CLEANUP_ERASE(salted_pin);
r = tpm2_util_pbkdf2_hmac_sha256(pin, strlen(pin), salt, salt_size, salted_pin);
diff --git a/src/cryptsetup/cryptsetup-tpm2.c b/src/cryptsetup/cryptsetup-tpm2.c
index c049b8a313..036f3d3a00 100644
--- a/src/cryptsetup/cryptsetup-tpm2.c
+++ b/src/cryptsetup/cryptsetup-tpm2.c
@@ -88,6 +88,8 @@ int acquire_tpm2_key(
const void *blob;
int r;
+ assert(salt || salt_size == 0);
+
if (!device) {
r = tpm2_find_device_auto(&auto_device);
if (r == -ENODEV)
@@ -165,7 +167,7 @@ int acquire_tpm2_key(
if (r < 0)
return r;
- if (salt) {
+ if (salt_size > 0) {
uint8_t salted_pin[SHA256_DIGEST_SIZE] = {};
CLEANUP_ERASE(salted_pin);
diff --git a/src/shared/tpm2-util.c b/src/shared/tpm2-util.c
index 4e382f691e..1d2d4ddda4 100644
--- a/src/shared/tpm2-util.c
+++ b/src/shared/tpm2-util.c
@@ -6041,6 +6041,7 @@ int tpm2_util_pbkdf2_hmac_sha256(const void *pass,
*/
static const uint8_t block_cnt[] = { 0, 0, 0, 1 };
+ assert (salt);
assert (saltlen > 0);
assert (saltlen <= (SIZE_MAX - sizeof(block_cnt)));
assert (passlen > 0);