Commit 4d2d15c0 authored by Chuck Lever's avatar Chuck Lever

SUNRPC: Add RFC 8009 encryption KUnit tests

RFC 8009 provides sample encryption results. Add KUnit tests to
ensure our implementation derives the expected results for the
provided sample input.

I hate how large this test is, but using non-standard key usage
values means rfc8009_encrypt_case() can't simply reuse ->import_ctx
to allocate and key its ciphers; and the test provides its own
confounders, which means krb5_etm_encrypt() can't be used directly.
Tested-by: default avatarScott Mayhew <smayhew@redhat.com>
Reviewed-by: default avatarSimo Sorce <simo@redhat.com>
Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
parent 003caf4f
...@@ -886,8 +886,25 @@ gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len, ...@@ -886,8 +886,25 @@ gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
return ret; return ret;
} }
static u32 /**
krb5_etm_checksum(struct crypto_sync_skcipher *cipher, * krb5_etm_checksum - Compute a MAC for a GSS Wrap token
* @cipher: an initialized cipher transform
* @tfm: an initialized hash transform
* @body: xdr_buf containing an RPC message (body.len is the message length)
* @body_offset: byte offset into @body to start checksumming
* @cksumout: OUT: a buffer to be filled in with the computed HMAC
*
* Usually expressed as H = HMAC(K, IV | ciphertext)[1..h] .
*
* Caller provides the truncation length of the output token (h) in
* cksumout.len.
*
* Return values:
* %GSS_S_COMPLETE: Digest computed, @cksumout filled in
* %GSS_S_FAILURE: Call failed
*/
VISIBLE_IF_KUNIT
u32 krb5_etm_checksum(struct crypto_sync_skcipher *cipher,
struct crypto_ahash *tfm, const struct xdr_buf *body, struct crypto_ahash *tfm, const struct xdr_buf *body,
int body_offset, struct xdr_netobj *cksumout) int body_offset, struct xdr_netobj *cksumout)
{ {
...@@ -936,6 +953,7 @@ krb5_etm_checksum(struct crypto_sync_skcipher *cipher, ...@@ -936,6 +953,7 @@ krb5_etm_checksum(struct crypto_sync_skcipher *cipher,
kfree_sensitive(checksumdata); kfree_sensitive(checksumdata);
return err ? GSS_S_FAILURE : GSS_S_COMPLETE; return err ? GSS_S_FAILURE : GSS_S_COMPLETE;
} }
EXPORT_SYMBOL_IF_KUNIT(krb5_etm_checksum);
/** /**
* krb5_etm_encrypt - Encrypt using the RFC 8009 rules * krb5_etm_encrypt - Encrypt using the RFC 8009 rules
......
...@@ -221,6 +221,9 @@ int krb5_cbc_cts_encrypt(struct crypto_sync_skcipher *cts_tfm, ...@@ -221,6 +221,9 @@ int krb5_cbc_cts_encrypt(struct crypto_sync_skcipher *cts_tfm,
struct crypto_sync_skcipher *cbc_tfm, u32 offset, struct crypto_sync_skcipher *cbc_tfm, u32 offset,
struct xdr_buf *buf, struct page **pages, struct xdr_buf *buf, struct page **pages,
u8 *iv, unsigned int ivsize); u8 *iv, unsigned int ivsize);
u32 krb5_etm_checksum(struct crypto_sync_skcipher *cipher,
struct crypto_ahash *tfm, const struct xdr_buf *body,
int body_offset, struct xdr_netobj *cksumout);
#endif #endif
#endif /* _NET_SUNRPC_AUTH_GSS_KRB5_INTERNAL_H */ #endif /* _NET_SUNRPC_AUTH_GSS_KRB5_INTERNAL_H */
...@@ -30,6 +30,7 @@ struct gss_krb5_test_param { ...@@ -30,6 +30,7 @@ struct gss_krb5_test_param {
const struct xdr_netobj *plaintext; const struct xdr_netobj *plaintext;
const struct xdr_netobj *confounder; const struct xdr_netobj *confounder;
const struct xdr_netobj *expected_result; const struct xdr_netobj *expected_result;
const struct xdr_netobj *expected_hmac;
const struct xdr_netobj *next_iv; const struct xdr_netobj *next_iv;
}; };
...@@ -1562,6 +1563,329 @@ static const struct gss_krb5_test_param rfc8009_checksum_test_params[] = { ...@@ -1562,6 +1563,329 @@ static const struct gss_krb5_test_param rfc8009_checksum_test_params[] = {
KUNIT_ARRAY_PARAM(rfc8009_checksum, rfc8009_checksum_test_params, KUNIT_ARRAY_PARAM(rfc8009_checksum, rfc8009_checksum_test_params,
gss_krb5_get_desc); gss_krb5_get_desc);
/*
* From RFC 8009 Appendix A. Test Vectors
*
* Sample encryptions (all using the default cipher state):
* --------------------------------------------------------
*
* These sample encryptions use the above sample key derivation results,
* including use of the same base-key and key usage values.
*
* This test material is copyright (c) 2016 IETF Trust and the
* persons identified as the document authors. All rights reserved.
*/
static const struct xdr_netobj rfc8009_enc_empty_plaintext = {
.len = 0,
};
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_short_plaintext,
0x00, 0x01, 0x02, 0x03, 0x04, 0x05
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_block_plaintext,
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_long_plaintext,
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x10, 0x11, 0x12, 0x13, 0x14
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test1_confounder,
0x7e, 0x58, 0x95, 0xea, 0xf2, 0x67, 0x24, 0x35,
0xba, 0xd8, 0x17, 0xf5, 0x45, 0xa3, 0x71, 0x48
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test1_expected_result,
0xef, 0x85, 0xfb, 0x89, 0x0b, 0xb8, 0x47, 0x2f,
0x4d, 0xab, 0x20, 0x39, 0x4d, 0xca, 0x78, 0x1d
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test1_expected_hmac,
0xad, 0x87, 0x7e, 0xda, 0x39, 0xd5, 0x0c, 0x87,
0x0c, 0x0d, 0x5a, 0x0a, 0x8e, 0x48, 0xc7, 0x18
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test2_confounder,
0x7b, 0xca, 0x28, 0x5e, 0x2f, 0xd4, 0x13, 0x0f,
0xb5, 0x5b, 0x1a, 0x5c, 0x83, 0xbc, 0x5b, 0x24
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test2_expected_result,
0x84, 0xd7, 0xf3, 0x07, 0x54, 0xed, 0x98, 0x7b,
0xab, 0x0b, 0xf3, 0x50, 0x6b, 0xeb, 0x09, 0xcf,
0xb5, 0x54, 0x02, 0xce, 0xf7, 0xe6
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test2_expected_hmac,
0x87, 0x7c, 0xe9, 0x9e, 0x24, 0x7e, 0x52, 0xd1,
0x6e, 0xd4, 0x42, 0x1d, 0xfd, 0xf8, 0x97, 0x6c
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test3_confounder,
0x56, 0xab, 0x21, 0x71, 0x3f, 0xf6, 0x2c, 0x0a,
0x14, 0x57, 0x20, 0x0f, 0x6f, 0xa9, 0x94, 0x8f
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test3_expected_result,
0x35, 0x17, 0xd6, 0x40, 0xf5, 0x0d, 0xdc, 0x8a,
0xd3, 0x62, 0x87, 0x22, 0xb3, 0x56, 0x9d, 0x2a,
0xe0, 0x74, 0x93, 0xfa, 0x82, 0x63, 0x25, 0x40,
0x80, 0xea, 0x65, 0xc1, 0x00, 0x8e, 0x8f, 0xc2
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test3_expected_hmac,
0x95, 0xfb, 0x48, 0x52, 0xe7, 0xd8, 0x3e, 0x1e,
0x7c, 0x48, 0xc3, 0x7e, 0xeb, 0xe6, 0xb0, 0xd3
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test4_confounder,
0xa7, 0xa4, 0xe2, 0x9a, 0x47, 0x28, 0xce, 0x10,
0x66, 0x4f, 0xb6, 0x4e, 0x49, 0xad, 0x3f, 0xac
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test4_expected_result,
0x72, 0x0f, 0x73, 0xb1, 0x8d, 0x98, 0x59, 0xcd,
0x6c, 0xcb, 0x43, 0x46, 0x11, 0x5c, 0xd3, 0x36,
0xc7, 0x0f, 0x58, 0xed, 0xc0, 0xc4, 0x43, 0x7c,
0x55, 0x73, 0x54, 0x4c, 0x31, 0xc8, 0x13, 0xbc,
0xe1, 0xe6, 0xd0, 0x72, 0xc1
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test4_expected_hmac,
0x86, 0xb3, 0x9a, 0x41, 0x3c, 0x2f, 0x92, 0xca,
0x9b, 0x83, 0x34, 0xa2, 0x87, 0xff, 0xcb, 0xfc
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test5_confounder,
0xf7, 0x64, 0xe9, 0xfa, 0x15, 0xc2, 0x76, 0x47,
0x8b, 0x2c, 0x7d, 0x0c, 0x4e, 0x5f, 0x58, 0xe4
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test5_expected_result,
0x41, 0xf5, 0x3f, 0xa5, 0xbf, 0xe7, 0x02, 0x6d,
0x91, 0xfa, 0xf9, 0xbe, 0x95, 0x91, 0x95, 0xa0
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test5_expected_hmac,
0x58, 0x70, 0x72, 0x73, 0xa9, 0x6a, 0x40, 0xf0,
0xa0, 0x19, 0x60, 0x62, 0x1a, 0xc6, 0x12, 0x74,
0x8b, 0x9b, 0xbf, 0xbe, 0x7e, 0xb4, 0xce, 0x3c
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test6_confounder,
0xb8, 0x0d, 0x32, 0x51, 0xc1, 0xf6, 0x47, 0x14,
0x94, 0x25, 0x6f, 0xfe, 0x71, 0x2d, 0x0b, 0x9a
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test6_expected_result,
0x4e, 0xd7, 0xb3, 0x7c, 0x2b, 0xca, 0xc8, 0xf7,
0x4f, 0x23, 0xc1, 0xcf, 0x07, 0xe6, 0x2b, 0xc7,
0xb7, 0x5f, 0xb3, 0xf6, 0x37, 0xb9
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test6_expected_hmac,
0xf5, 0x59, 0xc7, 0xf6, 0x64, 0xf6, 0x9e, 0xab,
0x7b, 0x60, 0x92, 0x23, 0x75, 0x26, 0xea, 0x0d,
0x1f, 0x61, 0xcb, 0x20, 0xd6, 0x9d, 0x10, 0xf2
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test7_confounder,
0x53, 0xbf, 0x8a, 0x0d, 0x10, 0x52, 0x65, 0xd4,
0xe2, 0x76, 0x42, 0x86, 0x24, 0xce, 0x5e, 0x63
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test7_expected_result,
0xbc, 0x47, 0xff, 0xec, 0x79, 0x98, 0xeb, 0x91,
0xe8, 0x11, 0x5c, 0xf8, 0xd1, 0x9d, 0xac, 0x4b,
0xbb, 0xe2, 0xe1, 0x63, 0xe8, 0x7d, 0xd3, 0x7f,
0x49, 0xbe, 0xca, 0x92, 0x02, 0x77, 0x64, 0xf6
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test7_expected_hmac,
0x8c, 0xf5, 0x1f, 0x14, 0xd7, 0x98, 0xc2, 0x27,
0x3f, 0x35, 0xdf, 0x57, 0x4d, 0x1f, 0x93, 0x2e,
0x40, 0xc4, 0xff, 0x25, 0x5b, 0x36, 0xa2, 0x66
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test8_confounder,
0x76, 0x3e, 0x65, 0x36, 0x7e, 0x86, 0x4f, 0x02,
0xf5, 0x51, 0x53, 0xc7, 0xe3, 0xb5, 0x8a, 0xf1
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test8_expected_result,
0x40, 0x01, 0x3e, 0x2d, 0xf5, 0x8e, 0x87, 0x51,
0x95, 0x7d, 0x28, 0x78, 0xbc, 0xd2, 0xd6, 0xfe,
0x10, 0x1c, 0xcf, 0xd5, 0x56, 0xcb, 0x1e, 0xae,
0x79, 0xdb, 0x3c, 0x3e, 0xe8, 0x64, 0x29, 0xf2,
0xb2, 0xa6, 0x02, 0xac, 0x86
);
DEFINE_HEX_XDR_NETOBJ(rfc8009_enc_test8_expected_hmac,
0xfe, 0xf6, 0xec, 0xb6, 0x47, 0xd6, 0x29, 0x5f,
0xae, 0x07, 0x7a, 0x1f, 0xeb, 0x51, 0x75, 0x08,
0xd2, 0xc1, 0x6b, 0x41, 0x92, 0xe0, 0x1f, 0x62
);
static const struct gss_krb5_test_param rfc8009_encrypt_test_params[] = {
{
.desc = "Encrypt empty plaintext with aes128-cts-hmac-sha256-128",
.enctype = ENCTYPE_AES128_CTS_HMAC_SHA256_128,
.plaintext = &rfc8009_enc_empty_plaintext,
.confounder = &rfc8009_enc_test1_confounder,
.base_key = &aes128_cts_hmac_sha256_128_basekey,
.expected_result = &rfc8009_enc_test1_expected_result,
.expected_hmac = &rfc8009_enc_test1_expected_hmac,
},
{
.desc = "Encrypt short plaintext with aes128-cts-hmac-sha256-128",
.enctype = ENCTYPE_AES128_CTS_HMAC_SHA256_128,
.plaintext = &rfc8009_enc_short_plaintext,
.confounder = &rfc8009_enc_test2_confounder,
.base_key = &aes128_cts_hmac_sha256_128_basekey,
.expected_result = &rfc8009_enc_test2_expected_result,
.expected_hmac = &rfc8009_enc_test2_expected_hmac,
},
{
.desc = "Encrypt block plaintext with aes128-cts-hmac-sha256-128",
.enctype = ENCTYPE_AES128_CTS_HMAC_SHA256_128,
.plaintext = &rfc8009_enc_block_plaintext,
.confounder = &rfc8009_enc_test3_confounder,
.base_key = &aes128_cts_hmac_sha256_128_basekey,
.expected_result = &rfc8009_enc_test3_expected_result,
.expected_hmac = &rfc8009_enc_test3_expected_hmac,
},
{
.desc = "Encrypt long plaintext with aes128-cts-hmac-sha256-128",
.enctype = ENCTYPE_AES128_CTS_HMAC_SHA256_128,
.plaintext = &rfc8009_enc_long_plaintext,
.confounder = &rfc8009_enc_test4_confounder,
.base_key = &aes128_cts_hmac_sha256_128_basekey,
.expected_result = &rfc8009_enc_test4_expected_result,
.expected_hmac = &rfc8009_enc_test4_expected_hmac,
},
{
.desc = "Encrypt empty plaintext with aes256-cts-hmac-sha384-192",
.enctype = ENCTYPE_AES256_CTS_HMAC_SHA384_192,
.plaintext = &rfc8009_enc_empty_plaintext,
.confounder = &rfc8009_enc_test5_confounder,
.base_key = &aes256_cts_hmac_sha384_192_basekey,
.expected_result = &rfc8009_enc_test5_expected_result,
.expected_hmac = &rfc8009_enc_test5_expected_hmac,
},
{
.desc = "Encrypt short plaintext with aes256-cts-hmac-sha384-192",
.enctype = ENCTYPE_AES256_CTS_HMAC_SHA384_192,
.plaintext = &rfc8009_enc_short_plaintext,
.confounder = &rfc8009_enc_test6_confounder,
.base_key = &aes256_cts_hmac_sha384_192_basekey,
.expected_result = &rfc8009_enc_test6_expected_result,
.expected_hmac = &rfc8009_enc_test6_expected_hmac,
},
{
.desc = "Encrypt block plaintext with aes256-cts-hmac-sha384-192",
.enctype = ENCTYPE_AES256_CTS_HMAC_SHA384_192,
.plaintext = &rfc8009_enc_block_plaintext,
.confounder = &rfc8009_enc_test7_confounder,
.base_key = &aes256_cts_hmac_sha384_192_basekey,
.expected_result = &rfc8009_enc_test7_expected_result,
.expected_hmac = &rfc8009_enc_test7_expected_hmac,
},
{
.desc = "Encrypt long plaintext with aes256-cts-hmac-sha384-192",
.enctype = ENCTYPE_AES256_CTS_HMAC_SHA384_192,
.plaintext = &rfc8009_enc_long_plaintext,
.confounder = &rfc8009_enc_test8_confounder,
.base_key = &aes256_cts_hmac_sha384_192_basekey,
.expected_result = &rfc8009_enc_test8_expected_result,
.expected_hmac = &rfc8009_enc_test8_expected_hmac,
},
};
/* Creates the function rfc8009_encrypt_gen_params */
KUNIT_ARRAY_PARAM(rfc8009_encrypt, rfc8009_encrypt_test_params,
gss_krb5_get_desc);
static void rfc8009_encrypt_case(struct kunit *test)
{
const struct gss_krb5_test_param *param = test->param_value;
struct crypto_sync_skcipher *cts_tfm, *cbc_tfm;
const struct gss_krb5_enctype *gk5e;
struct xdr_netobj Ke, Ki, checksum;
u8 usage_data[GSS_KRB5_K5CLENGTH];
struct xdr_netobj usage = {
.data = usage_data,
.len = sizeof(usage_data),
};
struct crypto_ahash *ahash_tfm;
struct xdr_buf buf;
void *text;
size_t len;
u32 err;
/* Arrange */
gk5e = gss_krb5_lookup_enctype(param->enctype);
KUNIT_ASSERT_NOT_NULL(test, gk5e);
*(__be32 *)usage.data = cpu_to_be32(2);
Ke.len = gk5e->Ke_length;
Ke.data = kunit_kzalloc(test, Ke.len, GFP_KERNEL);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, Ke.data);
usage.data[4] = KEY_USAGE_SEED_ENCRYPTION;
err = gk5e->derive_key(gk5e, param->base_key, &Ke,
&usage, GFP_KERNEL);
KUNIT_ASSERT_EQ(test, err, 0);
cbc_tfm = crypto_alloc_sync_skcipher(gk5e->aux_cipher, 0, 0);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cbc_tfm);
err = crypto_sync_skcipher_setkey(cbc_tfm, Ke.data, Ke.len);
KUNIT_ASSERT_EQ(test, err, 0);
cts_tfm = crypto_alloc_sync_skcipher(gk5e->encrypt_name, 0, 0);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cts_tfm);
err = crypto_sync_skcipher_setkey(cts_tfm, Ke.data, Ke.len);
KUNIT_ASSERT_EQ(test, err, 0);
len = param->confounder->len + param->plaintext->len;
text = kunit_kzalloc(test, len, GFP_KERNEL);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, text);
memcpy(text, param->confounder->data, param->confounder->len);
memcpy(text + param->confounder->len, param->plaintext->data,
param->plaintext->len);
memset(&buf, 0, sizeof(buf));
buf.head[0].iov_base = text;
buf.head[0].iov_len = param->confounder->len + param->plaintext->len;
buf.len = buf.head[0].iov_len;
checksum.len = gk5e->cksumlength;
checksum.data = kunit_kzalloc(test, checksum.len, GFP_KERNEL);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, checksum.data);
Ki.len = gk5e->Ki_length;
Ki.data = kunit_kzalloc(test, Ki.len, GFP_KERNEL);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, Ki.data);
usage.data[4] = KEY_USAGE_SEED_INTEGRITY;
err = gk5e->derive_key(gk5e, param->base_key, &Ki,
&usage, GFP_KERNEL);
KUNIT_ASSERT_EQ(test, err, 0);
ahash_tfm = crypto_alloc_ahash(gk5e->cksum_name, 0, CRYPTO_ALG_ASYNC);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ahash_tfm);
err = crypto_ahash_setkey(ahash_tfm, Ki.data, Ki.len);
KUNIT_ASSERT_EQ(test, err, 0);
/* Act */
err = krb5_cbc_cts_encrypt(cts_tfm, cbc_tfm, 0, &buf, NULL, NULL, 0);
KUNIT_ASSERT_EQ(test, err, 0);
err = krb5_etm_checksum(cts_tfm, ahash_tfm, &buf, 0, &checksum);
KUNIT_ASSERT_EQ(test, err, 0);
/* Assert */
KUNIT_EXPECT_EQ_MSG(test,
param->expected_result->len, buf.len,
"ciphertext length mismatch");
KUNIT_EXPECT_EQ_MSG(test,
memcmp(param->expected_result->data,
buf.head[0].iov_base,
param->expected_result->len), 0,
"ciphertext mismatch");
KUNIT_EXPECT_EQ_MSG(test, memcmp(param->expected_hmac->data,
checksum.data,
checksum.len), 0,
"HMAC mismatch");
crypto_free_ahash(ahash_tfm);
crypto_free_sync_skcipher(cts_tfm);
crypto_free_sync_skcipher(cbc_tfm);
}
static struct kunit_case rfc8009_test_cases[] = { static struct kunit_case rfc8009_test_cases[] = {
{ {
.name = "RFC 8009 key derivation", .name = "RFC 8009 key derivation",
...@@ -1573,6 +1897,11 @@ static struct kunit_case rfc8009_test_cases[] = { ...@@ -1573,6 +1897,11 @@ static struct kunit_case rfc8009_test_cases[] = {
.run_case = checksum_case, .run_case = checksum_case,
.generate_params = rfc8009_checksum_gen_params, .generate_params = rfc8009_checksum_gen_params,
}, },
{
.name = "RFC 8009 encryption",
.run_case = rfc8009_encrypt_case,
.generate_params = rfc8009_encrypt_gen_params,
},
}; };
static struct kunit_suite rfc8009_suite = { static struct kunit_suite rfc8009_suite = {
......
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