| 1 |
From 754862899058cfb5f2341c81f9e04dd2f7b37056 Mon Sep 17 00:00:00 2001 |
| 2 |
From: Clemens Lang <cllang@redhat.com> |
| 3 |
Date: Thu, 17 Nov 2022 18:37:17 +0100 |
| 4 |
Subject: [PATCH] pbkdf2: Set minimum password length of 8 bytes |
| 5 |
MIME-Version: 1.0 |
| 6 |
Content-Type: text/plain; charset=UTF-8 |
| 7 |
Content-Transfer-Encoding: 8bit |
| 8 |
|
| 9 |
The Implementation Guidance for FIPS 140-3 says in section D.N |
| 10 |
"Password-Based Key Derivation for Storage Applications" that "the |
| 11 |
vendor shall document in the module’s Security Policy the length of |
| 12 |
a password/passphrase used in key derivation and establish an upper |
| 13 |
bound for the probability of having this parameter guessed at random. |
| 14 |
This probability shall take into account not only the length of the |
| 15 |
password/passphrase, but also the difficulty of guessing it. The |
| 16 |
decision on the minimum length of a password used for key derivation is |
| 17 |
the vendor’s, but the vendor shall at a minimum informally justify the |
| 18 |
decision." |
| 19 |
|
| 20 |
We are choosing a minimum password length of 8 bytes, because NIST's |
| 21 |
ACVP testing uses passwords as short as 8 bytes, and requiring longer |
| 22 |
passwords combined with an implicit indicator (i.e., returning an error) |
| 23 |
would cause the module to fail ACVP testing. |
| 24 |
|
| 25 |
Signed-off-by: Clemens Lang <cllang@redhat.com> |
| 26 |
--- |
| 27 |
providers/implementations/kdfs/pbkdf2.c | 27 ++++++++++++++++++++++++- |
| 28 |
1 file changed, 26 insertions(+), 1 deletion(-) |
| 29 |
|
| 30 |
diff --git a/providers/implementations/kdfs/pbkdf2.c b/providers/implementations/kdfs/pbkdf2.c |
| 31 |
index 2a0ae63acc..aa0adce5e6 100644 |
| 32 |
--- a/providers/implementations/kdfs/pbkdf2.c |
| 33 |
+++ b/providers/implementations/kdfs/pbkdf2.c |
| 34 |
@@ -35,6 +35,21 @@ |
| 35 |
#define KDF_PBKDF2_MAX_KEY_LEN_DIGEST_RATIO 0xFFFFFFFF |
| 36 |
#define KDF_PBKDF2_MIN_ITERATIONS 1000 |
| 37 |
#define KDF_PBKDF2_MIN_SALT_LEN (128 / 8) |
| 38 |
+/* The Implementation Guidance for FIPS 140-3 says in section D.N |
| 39 |
+ * "Password-Based Key Derivation for Storage Applications" that "the vendor |
| 40 |
+ * shall document in the module’s Security Policy the length of |
| 41 |
+ * a password/passphrase used in key derivation and establish an upper bound |
| 42 |
+ * for the probability of having this parameter guessed at random. This |
| 43 |
+ * probability shall take into account not only the length of the |
| 44 |
+ * password/passphrase, but also the difficulty of guessing it. The decision on |
| 45 |
+ * the minimum length of a password used for key derivation is the vendor’s, |
| 46 |
+ * but the vendor shall at a minimum informally justify the decision." |
| 47 |
+ * |
| 48 |
+ * We are choosing a minimum password length of 8 bytes, because NIST's ACVP |
| 49 |
+ * testing uses passwords as short as 8 bytes, and requiring longer passwords |
| 50 |
+ * combined with an implicit indicator (i.e., returning an error) would cause |
| 51 |
+ * the module to fail ACVP testing. */ |
| 52 |
+#define KDF_PBKDF2_MIN_PASSWORD_LEN (8) |
| 53 |
|
| 54 |
static OSSL_FUNC_kdf_newctx_fn kdf_pbkdf2_new; |
| 55 |
static OSSL_FUNC_kdf_freectx_fn kdf_pbkdf2_free; |
| 56 |
@@ -186,9 +201,15 @@ static int kdf_pbkdf2_set_ctx_params(void *vctx, const OSSL_PARAM params[]) |
| 57 |
ctx->lower_bound_checks = pkcs5 == 0; |
| 58 |
} |
| 59 |
|
| 60 |
- if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PASSWORD)) != NULL) |
| 61 |
+ if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_PASSWORD)) != NULL) { |
| 62 |
+ if (ctx->lower_bound_checks != 0 |
| 63 |
+ && p->data_size < KDF_PBKDF2_MIN_PASSWORD_LEN) { |
| 64 |
+ ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH); |
| 65 |
+ return 0; |
| 66 |
+ } |
| 67 |
if (!pbkdf2_set_membuf(&ctx->pass, &ctx->pass_len, p)) |
| 68 |
return 0; |
| 69 |
+ } |
| 70 |
|
| 71 |
if ((p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SALT)) != NULL) { |
| 72 |
if (ctx->lower_bound_checks != 0 |
| 73 |
@@ -297,6 +318,10 @@ static int pbkdf2_derive(const char *pass, size_t passlen, |
| 74 |
} |
| 75 |
|
| 76 |
if (lower_bound_checks) { |
| 77 |
+ if (passlen < KDF_PBKDF2_MIN_PASSWORD_LEN) { |
| 78 |
+ ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH); |
| 79 |
+ return 0; |
| 80 |
+ } |
| 81 |
if ((keylen * 8) < KDF_PBKDF2_MIN_KEY_LEN_BITS) { |
| 82 |
ERR_raise(ERR_LIB_PROV, PROV_R_KEY_SIZE_TOO_SMALL); |
| 83 |
return 0; |
| 84 |
-- |
| 85 |
2.38.1 |
| 86 |
|
Parent Directory
| 
Revision Log
| 
Revision Graph
