strongswan: Add fix of CVE-2021-45079

Add a patch to fix CVE-2021-45079

Signed-off-by: Ranjitsinh Rathod <ranjitsinh.rathod@kpit.com>
Signed-off-by: Ranjitsinh Rathod <ranjitsinhrathod1991@gmail.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>

2 files changed, 157 insertions, 0 deletions

diff --git a/meta-networking/recipes-support/strongswan/files/CVE-2021-45079.patch b/meta-networking/recipes-support/strongswan/files/CVE-2021-45079.patch
new file mode 100644
index 0000000000..97aa6a0efc
--- /dev/null
+++ b/meta-networking/recipes-support/strongswan/files/CVE-2021-45079.patch
@@ -0,0 +1,156 @@
+From 76968cdd6b79f6ae40d674554e902ced192fd33e Mon Sep 17 00:00:00 2001
+From: Tobias Brunner <tobias@strongswan.org>
+Date: Tue, 14 Dec 2021 10:51:35 +0100
+Subject: [PATCH] eap-authenticator: Enforce failure if MSK generation fails
+
+Without this, the authentication succeeded if the server sent an early
+EAP-Success message for mutual, key-generating EAP methods like EAP-TLS,
+which may be used in EAP-only scenarios but would complete without server
+or client authentication.  For clients configured for such EAP-only
+scenarios, a rogue server could capture traffic after the tunnel is
+established or even access hosts behind the client.  For non-mutual EAP
+methods, public key server authentication has been enforced for a while.
+
+A server previously could also crash a client by sending an EAP-Success
+immediately without initiating an actual EAP method.
+
+Fixes: 0706c39cda52 ("added support for EAP methods not establishing an MSK")
+Fixes: CVE-2021-45079
+
+Upstream-Status: Backport [https://download.strongswan.org/security/CVE-2021-45079/strongswan-5.5.0-5.9.4_eap_success.patch]
+CVE: CVE-2021-45079
+Signed-off-by: Ranjitsinh Rathod <ranjitsinh.rathod@kpit.com>
+
+---
+ src/libcharon/plugins/eap_gtc/eap_gtc.c       |  2 +-
+ src/libcharon/plugins/eap_md5/eap_md5.c       |  2 +-
+ src/libcharon/plugins/eap_radius/eap_radius.c |  4 ++-
+ src/libcharon/sa/eap/eap_method.h             |  8 ++++-
+ .../ikev2/authenticators/eap_authenticator.c  | 32 ++++++++++++++++---
+ 5 files changed, 40 insertions(+), 8 deletions(-)
+
+diff --git a/src/libcharon/plugins/eap_gtc/eap_gtc.c b/src/libcharon/plugins/eap_gtc/eap_gtc.c
+index 95ba090b79ce..cffb6222c2f8 100644
+--- a/src/libcharon/plugins/eap_gtc/eap_gtc.c
++++ b/src/libcharon/plugins/eap_gtc/eap_gtc.c
+@@ -195,7 +195,7 @@ METHOD(eap_method_t, get_type, eap_type_t,
+ METHOD(eap_method_t, get_msk, status_t,
+        private_eap_gtc_t *this, chunk_t *msk)
+ {
+-       return FAILED;
++       return NOT_SUPPORTED;
+ }
+ 
+ METHOD(eap_method_t, get_identifier, uint8_t,
+diff --git a/src/libcharon/plugins/eap_md5/eap_md5.c b/src/libcharon/plugins/eap_md5/eap_md5.c
+index ab5f7ff6a823..3a92ad7c0a04 100644
+--- a/src/libcharon/plugins/eap_md5/eap_md5.c
++++ b/src/libcharon/plugins/eap_md5/eap_md5.c
+@@ -213,7 +213,7 @@ METHOD(eap_method_t, get_type, eap_type_t,
+ METHOD(eap_method_t, get_msk, status_t,
+        private_eap_md5_t *this, chunk_t *msk)
+ {
+-       return FAILED;
++       return NOT_SUPPORTED;
+ }
+ 
+ METHOD(eap_method_t, is_mutual, bool,
+diff --git a/src/libcharon/plugins/eap_radius/eap_radius.c b/src/libcharon/plugins/eap_radius/eap_radius.c
+index 2dc7a423e702..5336dead13d9 100644
+--- a/src/libcharon/plugins/eap_radius/eap_radius.c
++++ b/src/libcharon/plugins/eap_radius/eap_radius.c
+@@ -733,7 +733,9 @@ METHOD(eap_method_t, get_msk, status_t,
+                *out = msk;
+                return SUCCESS;
+        }
+-       return FAILED;
++       /* we assume the selected method did not establish an MSK, if it failed
++        * to establish one, process() would have failed */
++       return NOT_SUPPORTED;
+ }
+ 
+ METHOD(eap_method_t, get_identifier, uint8_t,
+diff --git a/src/libcharon/sa/eap/eap_method.h b/src/libcharon/sa/eap/eap_method.h
+index 0b5218dfec15..33564831f86e 100644
+--- a/src/libcharon/sa/eap/eap_method.h
++++ b/src/libcharon/sa/eap/eap_method.h
+@@ -114,10 +114,16 @@ struct eap_method_t {
+         * Not all EAP methods establish a shared secret. For implementations of
+         * the EAP-Identity method, get_msk() returns the received identity.
+         *
++        * @note Returning NOT_SUPPORTED is important for implementations of EAP
++        * methods that don't establish an MSK.  In particular as client because
++        * key-generating EAP methods MUST fail to process EAP-Success messages if
++        * no MSK is established.
++        *
+         * @param msk                   chunk receiving internal stored MSK
+         * @return
+-        *                                              - SUCCESS, or
++        *                                              - SUCCESS, if MSK is established
+         *                                              - FAILED, if MSK not established (yet)
++        *                                              - NOT_SUPPORTED, for non-MSK-establishing methods
+         */
+        status_t (*get_msk) (eap_method_t *this, chunk_t *msk);
+ 
+diff --git a/src/libcharon/sa/ikev2/authenticators/eap_authenticator.c b/src/libcharon/sa/ikev2/authenticators/eap_authenticator.c
+index e1e6cd7ee6f3..87548fc471a6 100644
+--- a/src/libcharon/sa/ikev2/authenticators/eap_authenticator.c
++++ b/src/libcharon/sa/ikev2/authenticators/eap_authenticator.c
+@@ -305,9 +305,17 @@ static eap_payload_t* server_process_eap(private_eap_authenticator_t *this,
+                                this->method->destroy(this->method);
+                                return server_initiate_eap(this, FALSE);
+                        }
+-                       if (this->method->get_msk(this->method, &this->msk) == SUCCESS)
++                       switch (this->method->get_msk(this->method, &this->msk))
+                        {
+-                               this->msk = chunk_clone(this->msk);
++                               case SUCCESS:
++                                       this->msk = chunk_clone(this->msk);
++                                       break;
++                               case NOT_SUPPORTED:
++                                       break;
++                               case FAILED:
++                               default:
++                                       DBG1(DBG_IKE, "failed to establish MSK");
++                                       goto failure;
+                        }
+                        if (vendor)
+                        {
+@@ -326,6 +334,7 @@ static eap_payload_t* server_process_eap(private_eap_authenticator_t *this,
+                        return eap_payload_create_code(EAP_SUCCESS, in->get_identifier(in));
+                case FAILED:
+                default:
++failure:
+                        /* type might have changed for virtual methods */
+                        type = this->method->get_type(this->method, &vendor);
+                        if (vendor)
+@@ -661,9 +670,24 @@ METHOD(authenticator_t, process_client, status_t,
+                                uint32_t vendor;
+                                auth_cfg_t *cfg;
+ 
+-                               if (this->method->get_msk(this->method, &this->msk) == SUCCESS)
++                               if (!this->method)
+                                {
+-                                       this->msk = chunk_clone(this->msk);
++                                       DBG1(DBG_IKE, "received unexpected %N",
++                                                eap_code_names, eap_payload->get_code(eap_payload));
++                                       return FAILED;
++                               }
++                               switch (this->method->get_msk(this->method, &this->msk))
++                               {
++                                       case SUCCESS:
++                                               this->msk = chunk_clone(this->msk);
++                                               break;
++                                       case NOT_SUPPORTED:
++                                               break;
++                                       case FAILED:
++                                       default:
++                                               DBG1(DBG_IKE, "received %N but failed to establish MSK",
++                                                        eap_code_names, eap_payload->get_code(eap_payload));
++                                               return FAILED;
+                                }
+                                type = this->method->get_type(this->method, &vendor);
+                                if (vendor)
+-- 
+2.25.1
+
diff --git a/meta-networking/recipes-support/strongswan/strongswan_5.8.4.bb b/meta-networking/recipes-support/strongswan/strongswan_5.8.4.bb
index b45b8074c4..8a5855fb87 100644
--- a/meta-networking/recipes-support/strongswan/strongswan_5.8.4.bb
+++ b/meta-networking/recipes-support/strongswan/strongswan_5.8.4.bb
@@ -13,6 +13,7 @@ SRC_URI = "http://download.strongswan.org/strongswan-${PV}.tar.bz2 \
            file://0001-Remove-obsolete-setting-regarding-the-Standard-Outpu.patch \
            file://CVE-2021-41990.patch \
            file://CVE-2021-41991.patch \
+           file://CVE-2021-45079.patch \
            "
 
 SRC_URI[md5sum] = "0634e7f40591bd3f6770e583c3f27d29"