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310 lines
13 KiB
310 lines
13 KiB
From 93bb4f5ba6fd79e72a75de20e209db219118a3a1 Mon Sep 17 00:00:00 2001 |
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From: Julien Rische <jrische@redhat.com> |
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Date: Wed, 2 Aug 2023 10:19:28 +0200 |
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Subject: [PATCH] [downstream] Revert "Don't issue session keys with deprecated |
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enctypes" |
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This reverts commit 1b57a4d134bbd0e7c52d5885a92eccc815726463. |
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--- |
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doc/admin/conf_files/krb5_conf.rst | 12 ------------ |
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doc/admin/enctypes.rst | 23 +++------------------- |
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src/include/k5-int.h | 4 ---- |
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src/kdc/kdc_util.c | 10 ---------- |
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src/lib/krb5/krb/get_in_tkt.c | 31 +++++++++++------------------- |
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src/lib/krb5/krb/init_ctx.c | 10 ---------- |
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src/tests/gssapi/t_enctypes.py | 3 +-- |
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src/tests/t_etype_info.py | 2 +- |
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src/tests/t_sesskeynego.py | 28 ++------------------------- |
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src/util/k5test.py | 4 ++-- |
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10 files changed, 20 insertions(+), 107 deletions(-) |
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diff --git a/doc/admin/conf_files/krb5_conf.rst b/doc/admin/conf_files/krb5_conf.rst |
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index ecdf917501..f22d5db11b 100644 |
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--- a/doc/admin/conf_files/krb5_conf.rst |
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+++ b/doc/admin/conf_files/krb5_conf.rst |
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@@ -95,18 +95,6 @@ Additionally, krb5.conf may include any of the relations described in |
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The libdefaults section may contain any of the following relations: |
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-**allow_des3** |
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- Permit the KDC to issue tickets with des3-cbc-sha1 session keys. |
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- In future releases, this flag will allow des3-cbc-sha1 to be used |
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- at all. The default value for this tag is false. (Added in |
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- release 1.21.) |
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- |
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-**allow_rc4** |
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- Permit the KDC to issue tickets with arcfour-hmac session keys. |
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- In future releases, this flag will allow arcfour-hmac to be used |
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- at all. The default value for this tag is false. (Added in |
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- release 1.21.) |
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- |
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**allow_weak_crypto** |
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If this flag is set to false, then weak encryption types (as noted |
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in :ref:`Encryption_types` in :ref:`kdc.conf(5)`) will be filtered |
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diff --git a/doc/admin/enctypes.rst b/doc/admin/enctypes.rst |
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index dce19ad43e..694922c0d9 100644 |
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--- a/doc/admin/enctypes.rst |
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+++ b/doc/admin/enctypes.rst |
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@@ -48,15 +48,12 @@ Session key selection |
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The KDC chooses the session key enctype by taking the intersection of |
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its **permitted_enctypes** list, the list of long-term keys for the |
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most recent kvno of the service, and the client's requested list of |
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-enctypes. Starting in krb5-1.21, all services are assumed to support |
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-aes256-cts-hmac-sha1-96; also, des3-cbc-sha1 and arcfour-hmac session |
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-keys will not be issued by default. |
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+enctypes. |
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Starting in krb5-1.11, it is possible to set a string attribute on a |
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service principal to control what session key enctypes the KDC may |
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-issue for service tickets for that principal, overriding the service's |
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-long-term keys and the assumption of aes256-cts-hmac-sha1-96 support. |
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-See :ref:`set_string` in :ref:`kadmin(1)` for details. |
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+issue for service tickets for that principal. See :ref:`set_string` |
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+in :ref:`kadmin(1)` for details. |
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Choosing enctypes for a service |
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@@ -90,20 +87,6 @@ affect how enctypes are chosen. |
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acceptable risk for your environment and the weak enctypes are |
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required for backward compatibility. |
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-**allow_des3** |
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- was added in release 1.21 and defaults to *false*. Unless this |
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- flag is set to *true*, the KDC will not issue tickets with |
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- des3-cbc-sha1 session keys. In a future release, this flag will |
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- control whether des3-cbc-sha1 is permitted in similar fashion to |
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- weak enctypes. |
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- |
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-**allow_rc4** |
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- was added in release 1.21 and defaults to *false*. Unless this |
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- flag is set to *true*, the KDC will not issue tickets with |
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- arcfour-hmac session keys. In a future release, this flag will |
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- control whether arcfour-hmac is permitted in similar fashion to |
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- weak enctypes. |
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- |
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**permitted_enctypes** |
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controls the set of enctypes that a service will permit for |
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session keys and for ticket and authenticator encryption. The KDC |
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diff --git a/src/include/k5-int.h b/src/include/k5-int.h |
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index 2f7791b775..1d1c8293f4 100644 |
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--- a/src/include/k5-int.h |
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+++ b/src/include/k5-int.h |
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@@ -180,8 +180,6 @@ typedef unsigned char u_char; |
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* matches the variable name. Keep these alphabetized. */ |
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#define KRB5_CONF_ACL_FILE "acl_file" |
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#define KRB5_CONF_ADMIN_SERVER "admin_server" |
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-#define KRB5_CONF_ALLOW_DES3 "allow_des3" |
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-#define KRB5_CONF_ALLOW_RC4 "allow_rc4" |
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#define KRB5_CONF_ALLOW_WEAK_CRYPTO "allow_weak_crypto" |
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#define KRB5_CONF_AUTH_TO_LOCAL "auth_to_local" |
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#define KRB5_CONF_AUTH_TO_LOCAL_NAMES "auth_to_local_names" |
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@@ -1240,8 +1238,6 @@ struct _krb5_context { |
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struct _kdb_log_context *kdblog_context; |
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krb5_boolean allow_weak_crypto; |
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- krb5_boolean allow_des3; |
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- krb5_boolean allow_rc4; |
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krb5_boolean ignore_acceptor_hostname; |
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krb5_boolean enforce_ok_as_delegate; |
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enum dns_canonhost dns_canonicalize_hostname; |
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diff --git a/src/kdc/kdc_util.c b/src/kdc/kdc_util.c |
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index e54cc751f9..75e04b73db 100644 |
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--- a/src/kdc/kdc_util.c |
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+++ b/src/kdc/kdc_util.c |
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@@ -1088,16 +1088,6 @@ select_session_keytype(krb5_context context, krb5_db_entry *server, |
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if (!krb5_is_permitted_enctype(context, ktype[i])) |
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continue; |
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- /* |
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- * Prevent these deprecated enctypes from being used as session keys |
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- * unless they are explicitly allowed. In the future they will be more |
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- * comprehensively disabled and eventually removed. |
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- */ |
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- if (ktype[i] == ENCTYPE_DES3_CBC_SHA1 && !context->allow_des3) |
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- continue; |
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- if (ktype[i] == ENCTYPE_ARCFOUR_HMAC && !context->allow_rc4) |
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- continue; |
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- |
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if (dbentry_supports_enctype(context, server, ktype[i])) |
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return ktype[i]; |
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} |
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diff --git a/src/lib/krb5/krb/get_in_tkt.c b/src/lib/krb5/krb/get_in_tkt.c |
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index ea089f0fcc..1b420a3ac2 100644 |
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--- a/src/lib/krb5/krb/get_in_tkt.c |
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+++ b/src/lib/krb5/krb/get_in_tkt.c |
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@@ -1582,31 +1582,22 @@ warn_pw_expiry(krb5_context context, krb5_get_init_creds_opt *options, |
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(*prompter)(context, data, 0, banner, 0, 0); |
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} |
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-/* Display a warning via the prompter if a deprecated enctype was used for |
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- * either the reply key or the session key. */ |
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+/* Display a warning via the prompter if des3-cbc-sha1 was used for either the |
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+ * reply key or the session key. */ |
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static void |
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-warn_deprecated(krb5_context context, krb5_init_creds_context ctx, |
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- krb5_enctype as_key_enctype) |
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+warn_des3(krb5_context context, krb5_init_creds_context ctx, |
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+ krb5_enctype as_key_enctype) |
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{ |
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- krb5_enctype etype; |
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- char encbuf[128], banner[256]; |
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+ const char *banner; |
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- if (ctx->prompter == NULL) |
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- return; |
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- |
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- if (krb5int_c_deprecated_enctype(as_key_enctype)) |
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- etype = as_key_enctype; |
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- else if (krb5int_c_deprecated_enctype(ctx->cred.keyblock.enctype)) |
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- etype = ctx->cred.keyblock.enctype; |
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- else |
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+ if (as_key_enctype != ENCTYPE_DES3_CBC_SHA1 && |
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+ ctx->cred.keyblock.enctype != ENCTYPE_DES3_CBC_SHA1) |
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return; |
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- |
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- if (krb5_enctype_to_name(etype, FALSE, encbuf, sizeof(encbuf)) != 0) |
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+ if (ctx->prompter == NULL) |
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return; |
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- snprintf(banner, sizeof(banner), |
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- _("Warning: encryption type %s used for authentication is " |
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- "deprecated and will be disabled"), encbuf); |
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+ banner = _("Warning: encryption type des3-cbc-sha1 used for " |
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+ "authentication is weak and will be disabled"); |
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/* PROMPTER_INVOCATION */ |
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(*ctx->prompter)(context, ctx->prompter_data, NULL, banner, 0, NULL); |
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} |
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@@ -1857,7 +1848,7 @@ init_creds_step_reply(krb5_context context, |
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ctx->complete = TRUE; |
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warn_pw_expiry(context, ctx->opt, ctx->prompter, ctx->prompter_data, |
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ctx->in_tkt_service, ctx->reply); |
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- warn_deprecated(context, ctx, encrypting_key.enctype); |
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+ warn_des3(context, ctx, encrypting_key.enctype); |
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cleanup: |
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krb5_free_pa_data(context, kdc_padata); |
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diff --git a/src/lib/krb5/krb/init_ctx.c b/src/lib/krb5/krb/init_ctx.c |
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index a6c2bbeb54..87b486c53f 100644 |
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--- a/src/lib/krb5/krb/init_ctx.c |
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+++ b/src/lib/krb5/krb/init_ctx.c |
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@@ -221,16 +221,6 @@ krb5_init_context_profile(profile_t profile, krb5_flags flags, |
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goto cleanup; |
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ctx->allow_weak_crypto = tmp; |
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- retval = get_boolean(ctx, KRB5_CONF_ALLOW_DES3, 0, &tmp); |
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- if (retval) |
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- goto cleanup; |
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- ctx->allow_des3 = tmp; |
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- |
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- retval = get_boolean(ctx, KRB5_CONF_ALLOW_RC4, 0, &tmp); |
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- if (retval) |
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- goto cleanup; |
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- ctx->allow_rc4 = tmp; |
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- |
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retval = get_boolean(ctx, KRB5_CONF_IGNORE_ACCEPTOR_HOSTNAME, 0, &tmp); |
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if (retval) |
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goto cleanup; |
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diff --git a/src/tests/gssapi/t_enctypes.py b/src/tests/gssapi/t_enctypes.py |
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index f5f11842e2..7494d7fcdb 100755 |
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--- a/src/tests/gssapi/t_enctypes.py |
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+++ b/src/tests/gssapi/t_enctypes.py |
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@@ -18,8 +18,7 @@ d_rc4 = 'DEPRECATED:arcfour-hmac' |
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# These tests make assumptions about the default enctype lists, so set |
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# them explicitly rather than relying on the library defaults. |
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supp='aes256-cts:normal aes128-cts:normal des3-cbc-sha1:normal rc4-hmac:normal' |
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-conf = {'libdefaults': {'permitted_enctypes': 'aes des3 rc4', |
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- 'allow_des3': 'true', 'allow_rc4': 'true'}, |
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+conf = {'libdefaults': {'permitted_enctypes': 'aes des3 rc4'}, |
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'realms': {'$realm': {'supported_enctypes': supp}}} |
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realm = K5Realm(krb5_conf=conf) |
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shutil.copyfile(realm.ccache, os.path.join(realm.testdir, 'save')) |
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diff --git a/src/tests/t_etype_info.py b/src/tests/t_etype_info.py |
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index 38cf96ca8f..c982508d8b 100644 |
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--- a/src/tests/t_etype_info.py |
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+++ b/src/tests/t_etype_info.py |
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@@ -1,7 +1,7 @@ |
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from k5test import * |
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supported_enctypes = 'aes128-cts des3-cbc-sha1 rc4-hmac' |
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-conf = {'libdefaults': {'allow_des3': 'true', 'allow_rc4': 'true'}, |
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+conf = {'libdefaults': {'allow_weak_crypto': 'true'}, |
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'realms': {'$realm': {'supported_enctypes': supported_enctypes}}} |
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realm = K5Realm(create_host=False, get_creds=False, krb5_conf=conf) |
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diff --git a/src/tests/t_sesskeynego.py b/src/tests/t_sesskeynego.py |
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index 5a213617b5..9024aee838 100755 |
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--- a/src/tests/t_sesskeynego.py |
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+++ b/src/tests/t_sesskeynego.py |
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@@ -25,8 +25,6 @@ conf3 = {'libdefaults': { |
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'default_tkt_enctypes': 'aes128-cts', |
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'default_tgs_enctypes': 'rc4-hmac,aes128-cts'}} |
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conf4 = {'libdefaults': {'permitted_enctypes': 'aes256-cts'}} |
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-conf5 = {'libdefaults': {'allow_rc4': 'true'}} |
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-conf6 = {'libdefaults': {'allow_des3': 'true'}} |
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# Test with client request and session_enctypes preferring aes128, but |
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# aes256 long-term key. |
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realm = K5Realm(krb5_conf=conf1, create_host=False, get_creds=False) |
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@@ -56,12 +54,10 @@ realm.run([kadminl, 'setstr', 'server', 'session_enctypes', |
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'aes128-cts,aes256-cts']) |
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test_kvno(realm, 'aes128-cts-hmac-sha1-96', 'aes256-cts-hmac-sha1-96') |
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-# 3b: Skip RC4 (as the KDC does not allow it for session keys by |
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-# default) and negotiate aes128-cts session key, with only an aes256 |
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-# long-term service key. |
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+# 3b: Negotiate rc4-hmac session key when principal only has aes256 long-term. |
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realm.run([kadminl, 'setstr', 'server', 'session_enctypes', |
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'rc4-hmac,aes128-cts,aes256-cts']) |
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-test_kvno(realm, 'aes128-cts-hmac-sha1-96', 'aes256-cts-hmac-sha1-96') |
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+test_kvno(realm, 'DEPRECATED:arcfour-hmac', 'aes256-cts-hmac-sha1-96') |
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realm.stop() |
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# 4: Check that permitted_enctypes is a default for session key enctypes. |
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@@ -71,24 +67,4 @@ realm.run([kvno, 'user'], |
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expected_trace=('etypes requested in TGS request: aes256-cts',)) |
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realm.stop() |
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-# 5: allow_rc4 permits negotiation of rc4-hmac session key. |
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-realm = K5Realm(krb5_conf=conf5, create_host=False, get_creds=False) |
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-realm.run([kadminl, 'addprinc', '-randkey', '-e', 'aes256-cts', 'server']) |
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-realm.run([kadminl, 'setstr', 'server', 'session_enctypes', 'rc4-hmac']) |
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-test_kvno(realm, 'DEPRECATED:arcfour-hmac', 'aes256-cts-hmac-sha1-96') |
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-realm.stop() |
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- |
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-# 6: allow_des3 permits negotiation of des3-cbc-sha1 session key. |
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-realm = K5Realm(krb5_conf=conf6, create_host=False, get_creds=False) |
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-realm.run([kadminl, 'addprinc', '-randkey', '-e', 'aes256-cts', 'server']) |
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-realm.run([kadminl, 'setstr', 'server', 'session_enctypes', 'des3-cbc-sha1']) |
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-test_kvno(realm, 'DEPRECATED:des3-cbc-sha1', 'aes256-cts-hmac-sha1-96') |
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-realm.stop() |
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- |
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-# 7: default config negotiates aes256-sha1 session key for RC4-only service. |
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-realm = K5Realm(create_host=False, get_creds=False) |
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-realm.run([kadminl, 'addprinc', '-randkey', '-e', 'rc4-hmac', 'server']) |
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-test_kvno(realm, 'aes256-cts-hmac-sha1-96', 'DEPRECATED:arcfour-hmac') |
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-realm.stop() |
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- |
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success('sesskeynego') |
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diff --git a/src/util/k5test.py b/src/util/k5test.py |
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index 8e5f5ba8e9..2a86c5cdfc 100644 |
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--- a/src/util/k5test.py |
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+++ b/src/util/k5test.py |
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@@ -1340,14 +1340,14 @@ _passes = [ |
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# Exercise the DES3 enctype. |
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('des3', None, |
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- {'libdefaults': {'permitted_enctypes': 'des3 aes256-sha1'}}, |
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+ {'libdefaults': {'permitted_enctypes': 'des3'}}, |
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{'realms': {'$realm': { |
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'supported_enctypes': 'des3-cbc-sha1:normal', |
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'master_key_type': 'des3-cbc-sha1'}}}), |
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# Exercise the arcfour enctype. |
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('arcfour', None, |
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- {'libdefaults': {'permitted_enctypes': 'rc4 aes256-sha1'}}, |
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+ {'libdefaults': {'permitted_enctypes': 'rc4'}}, |
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{'realms': {'$realm': { |
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'supported_enctypes': 'arcfour-hmac:normal', |
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'master_key_type': 'arcfour-hmac'}}}), |
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-- |
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2.41.0 |
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