[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
cron2 has uploaded a new patch set (#10) to the change originally created by
plaisthos. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email )
The following approvals got outdated and were removed:
Code-Review+2 by cron2
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Check PRF availability on initialisation and add --force-tls-key-material-export
We now warn a user if the TLS 1.0 PRF is not supported by the cryptographic
library of the system. Also add the option --force-tls-key-material-export
that automatically rejects clients that do not support TLS Keying Material
Export and automatically enable it when TLS 1.0 PRF support is not available.
Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Signed-off-by: Arne Schwabe
Acked-by: Gert Doering
Message-Id: <20240104140214.32196-1-g...@greenie.muc.de>
URL:
https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg27924.html
Signed-off-by: Gert Doering
---
M doc/man-sections/protocol-options.rst
M src/openvpn/crypto.c
M src/openvpn/crypto.h
M src/openvpn/multi.c
M src/openvpn/options.c
M src/openvpn/options.h
6 files changed, 84 insertions(+), 0 deletions(-)
git pull ssh://gerrit.openvpn.net:29418/openvpn refs/changes/60/460/10
diff --git a/doc/man-sections/protocol-options.rst
b/doc/man-sections/protocol-options.rst
index 948c0c8..8b061d2 100644
--- a/doc/man-sections/protocol-options.rst
+++ b/doc/man-sections/protocol-options.rst
@@ -242,3 +242,11 @@
a key renegotiation begins (default :code:`3600` seconds). This feature
allows for a graceful transition from old to new key, and removes the key
renegotiation sequence from the critical path of tunnel data forwarding.
+
+--force-tls-key-material-export
+ This option is only available in --mode server and forces to use
+ Keying Material Exporters (RFC 5705) for clients. This can be used to
+ simulate an environment where the cryptographic library does not support
+ the older method to generate data channel keys anymore. This option is
+ intended to be a test option and might be removed in a future OpenVPN
+ version without notice.
diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c
index e4452d7..2fca131 100644
--- a/src/openvpn/crypto.c
+++ b/src/openvpn/crypto.c
@@ -27,6 +27,7 @@
#endif
#include "syshead.h"
+#include
#include "crypto.h"
#include "error.h"
@@ -1789,3 +1790,22 @@
gc_free();
return ret;
}
+
+bool
+check_tls_prf_working(void)
+{
+/* Modern TLS libraries might no longer support the TLS 1.0 PRF with
+ * MD5+SHA1. This allows us to establish connections only
+ * with other 2.6.0+ OpenVPN peers.
+ * Do a simple dummy test here to see if it works. */
+const char *seed = "tls1-prf-test";
+const char *secret = "tls1-prf-test-secret";
+uint8_t out[8];
+uint8_t expected_out[] = { 'q', 'D', '\xfe', '%', '@', 's', 'u', '\x95' };
+
+int ret = ssl_tls1_PRF((uint8_t *)seed, (int) strlen(seed),
+ (uint8_t *)secret, (int) strlen(secret),
+ out, sizeof(out));
+
+return (ret && memcmp(out, expected_out, sizeof(out)) == 0);
+}
diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h
index 9255d38..4201524 100644
--- a/src/openvpn/crypto.h
+++ b/src/openvpn/crypto.h
@@ -593,4 +593,12 @@
return kt;
}
+/**
+ * Checks if the current TLS library supports the TLS 1.0 PRF with MD5+SHA1
+ * that OpenVPN uses when TLS Keying Material Export is not available.
+ *
+ * @return true if supported, false otherwise.
+ */
+bool check_tls_prf_working(void);
+
#endif /* CRYPTO_H */
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 8b490ed..f4f0b8a 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -1830,6 +1830,16 @@
{
o->imported_protocol_flags |= CO_USE_TLS_KEY_MATERIAL_EXPORT;
}
+else if (o->force_key_material_export)
+{
+msg(M_INFO, "PUSH: client does not support TLS Keying Material "
+"Exporters but --force-tls-key-material-export is enabled.");
+auth_set_client_reason(tls_multi, "Client incompatible with this "
+ "server. Keying Material Exporters (RFC 5705) "
+ "support missing. Upgrade to a client that "
+ "supports this feature (OpenVPN 2.6.0+).");
+return false;
+}
if (proto & IV_PROTO_DYN_TLS_CRYPT)
{
o->imported_protocol_flags |= CO_USE_DYNAMIC_TLS_CRYPT;
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index e498114..1b28a19 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1561,6 +1561,7 @@
SHOW_STR(auth_user_pass_verify_script);
SHOW_BOOL(auth_user_pass_verify_script_via_file);
SHOW_BOOL(auth_token_generate);
+SHOW_BOOL(force_key_material_export);
SHOW_INT(auth_token_lifetime);
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
cron2 has submitted this change. (
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email )
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Check PRF availability on initialisation and add --force-tls-key-material-export
We now warn a user if the TLS 1.0 PRF is not supported by the cryptographic
library of the system. Also add the option --force-tls-key-material-export
that automatically rejects clients that do not support TLS Keying Material
Export and automatically enable it when TLS 1.0 PRF support is not available.
Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Signed-off-by: Arne Schwabe
Acked-by: Gert Doering
Message-Id: <20240104140214.32196-1-g...@greenie.muc.de>
URL:
https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg27924.html
Signed-off-by: Gert Doering
---
M doc/man-sections/protocol-options.rst
M src/openvpn/crypto.c
M src/openvpn/crypto.h
M src/openvpn/multi.c
M src/openvpn/options.c
M src/openvpn/options.h
6 files changed, 84 insertions(+), 0 deletions(-)
diff --git a/doc/man-sections/protocol-options.rst
b/doc/man-sections/protocol-options.rst
index 948c0c8..8b061d2 100644
--- a/doc/man-sections/protocol-options.rst
+++ b/doc/man-sections/protocol-options.rst
@@ -242,3 +242,11 @@
a key renegotiation begins (default :code:`3600` seconds). This feature
allows for a graceful transition from old to new key, and removes the key
renegotiation sequence from the critical path of tunnel data forwarding.
+
+--force-tls-key-material-export
+ This option is only available in --mode server and forces to use
+ Keying Material Exporters (RFC 5705) for clients. This can be used to
+ simulate an environment where the cryptographic library does not support
+ the older method to generate data channel keys anymore. This option is
+ intended to be a test option and might be removed in a future OpenVPN
+ version without notice.
diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c
index e4452d7..2fca131 100644
--- a/src/openvpn/crypto.c
+++ b/src/openvpn/crypto.c
@@ -27,6 +27,7 @@
#endif
#include "syshead.h"
+#include
#include "crypto.h"
#include "error.h"
@@ -1789,3 +1790,22 @@
gc_free();
return ret;
}
+
+bool
+check_tls_prf_working(void)
+{
+/* Modern TLS libraries might no longer support the TLS 1.0 PRF with
+ * MD5+SHA1. This allows us to establish connections only
+ * with other 2.6.0+ OpenVPN peers.
+ * Do a simple dummy test here to see if it works. */
+const char *seed = "tls1-prf-test";
+const char *secret = "tls1-prf-test-secret";
+uint8_t out[8];
+uint8_t expected_out[] = { 'q', 'D', '\xfe', '%', '@', 's', 'u', '\x95' };
+
+int ret = ssl_tls1_PRF((uint8_t *)seed, (int) strlen(seed),
+ (uint8_t *)secret, (int) strlen(secret),
+ out, sizeof(out));
+
+return (ret && memcmp(out, expected_out, sizeof(out)) == 0);
+}
diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h
index 9255d38..4201524 100644
--- a/src/openvpn/crypto.h
+++ b/src/openvpn/crypto.h
@@ -593,4 +593,12 @@
return kt;
}
+/**
+ * Checks if the current TLS library supports the TLS 1.0 PRF with MD5+SHA1
+ * that OpenVPN uses when TLS Keying Material Export is not available.
+ *
+ * @return true if supported, false otherwise.
+ */
+bool check_tls_prf_working(void);
+
#endif /* CRYPTO_H */
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 8b490ed..f4f0b8a 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -1830,6 +1830,16 @@
{
o->imported_protocol_flags |= CO_USE_TLS_KEY_MATERIAL_EXPORT;
}
+else if (o->force_key_material_export)
+{
+msg(M_INFO, "PUSH: client does not support TLS Keying Material "
+"Exporters but --force-tls-key-material-export is enabled.");
+auth_set_client_reason(tls_multi, "Client incompatible with this "
+ "server. Keying Material Exporters (RFC 5705) "
+ "support missing. Upgrade to a client that "
+ "supports this feature (OpenVPN 2.6.0+).");
+return false;
+}
if (proto & IV_PROTO_DYN_TLS_CRYPT)
{
o->imported_protocol_flags |= CO_USE_DYNAMIC_TLS_CRYPT;
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index e498114..1b28a19 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1561,6 +1561,7 @@
SHOW_STR(auth_user_pass_verify_script);
SHOW_BOOL(auth_user_pass_verify_script_via_file);
SHOW_BOOL(auth_token_generate);
+SHOW_BOOL(force_key_material_export);
SHOW_INT(auth_token_lifetime);
SHOW_STR_INLINE(auth_token_secret_file);
#if PORT_SHARE
@@ -2802,6 +2803,11 @@
{
msg(M_USAGE, "--vlan-tagging requires --mode server");
}
+
+if
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld, plaisthos. cron2 has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 9: Code-Review+2 (1 comment) Patchset: PS9: back to +2 - manipulating expected_out or setting ret=0 now leads to "it failed!" and the code as is pretends the PRF worked. Didn't test FIPS mode, but "set ret=0" as a test case should be good enough. -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 9 Gerrit-Owner: plaisthos Gerrit-Reviewer: cron2 Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: plaisthos Gerrit-Attention: flichtenheld Gerrit-Comment-Date: Thu, 04 Jan 2024 14:01:55 + Gerrit-HasComments: Yes Gerrit-Has-Labels: Yes Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: cron2, flichtenheld. plaisthos has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 8: (1 comment) File src/openvpn/crypto.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/46b9a5e4_f4d733cf : PS8, Line 1809: return (ret && memcmp(out, expected_out, sizeof(out)) != 0); > It pains me to return to "-2" again, but there is something really weird > going on here - to see what […] O my got I really butchered that one. -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 8 Gerrit-Owner: plaisthos Gerrit-Reviewer: cron2 Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: cron2 Gerrit-Attention: flichtenheld Gerrit-Comment-Date: Thu, 04 Jan 2024 12:45:54 + Gerrit-HasComments: Yes Gerrit-Has-Labels: No Comment-In-Reply-To: cron2 Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld, plaisthos.
Hello cron2, flichtenheld,
I'd like you to reexamine a change. Please visit
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email
to look at the new patch set (#9).
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Check PRF availability on initialisation and add --force-tls-key-material-export
We now warn a user if the TLS 1.0 PRF is not supported by the cryptographic
library of the system. Also add the option --force-tls-key-material-export
that automatically rejects clients that do not support TLS Keying Material
Export and automatically enable it when TLS 1.0 PRF support is not available.
Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Signed-off-by: Arne Schwabe
---
M doc/man-sections/protocol-options.rst
M src/openvpn/crypto.c
M src/openvpn/crypto.h
M src/openvpn/multi.c
M src/openvpn/options.c
M src/openvpn/options.h
6 files changed, 84 insertions(+), 0 deletions(-)
git pull ssh://gerrit.openvpn.net:29418/openvpn refs/changes/60/460/9
diff --git a/doc/man-sections/protocol-options.rst
b/doc/man-sections/protocol-options.rst
index 948c0c8..8b061d2 100644
--- a/doc/man-sections/protocol-options.rst
+++ b/doc/man-sections/protocol-options.rst
@@ -242,3 +242,11 @@
a key renegotiation begins (default :code:`3600` seconds). This feature
allows for a graceful transition from old to new key, and removes the key
renegotiation sequence from the critical path of tunnel data forwarding.
+
+--force-tls-key-material-export
+ This option is only available in --mode server and forces to use
+ Keying Material Exporters (RFC 5705) for clients. This can be used to
+ simulate an environment where the cryptographic library does not support
+ the older method to generate data channel keys anymore. This option is
+ intended to be a test option and might be removed in a future OpenVPN
+ version without notice.
diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c
index e4452d7..2fca131 100644
--- a/src/openvpn/crypto.c
+++ b/src/openvpn/crypto.c
@@ -27,6 +27,7 @@
#endif
#include "syshead.h"
+#include
#include "crypto.h"
#include "error.h"
@@ -1789,3 +1790,22 @@
gc_free();
return ret;
}
+
+bool
+check_tls_prf_working(void)
+{
+/* Modern TLS libraries might no longer support the TLS 1.0 PRF with
+ * MD5+SHA1. This allows us to establish connections only
+ * with other 2.6.0+ OpenVPN peers.
+ * Do a simple dummy test here to see if it works. */
+const char *seed = "tls1-prf-test";
+const char *secret = "tls1-prf-test-secret";
+uint8_t out[8];
+uint8_t expected_out[] = { 'q', 'D', '\xfe', '%', '@', 's', 'u', '\x95' };
+
+int ret = ssl_tls1_PRF((uint8_t *)seed, (int) strlen(seed),
+ (uint8_t *)secret, (int) strlen(secret),
+ out, sizeof(out));
+
+return (ret && memcmp(out, expected_out, sizeof(out)) == 0);
+}
diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h
index 9255d38..4201524 100644
--- a/src/openvpn/crypto.h
+++ b/src/openvpn/crypto.h
@@ -593,4 +593,12 @@
return kt;
}
+/**
+ * Checks if the current TLS library supports the TLS 1.0 PRF with MD5+SHA1
+ * that OpenVPN uses when TLS Keying Material Export is not available.
+ *
+ * @return true if supported, false otherwise.
+ */
+bool check_tls_prf_working(void);
+
#endif /* CRYPTO_H */
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 8b490ed..f4f0b8a 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -1830,6 +1830,16 @@
{
o->imported_protocol_flags |= CO_USE_TLS_KEY_MATERIAL_EXPORT;
}
+else if (o->force_key_material_export)
+{
+msg(M_INFO, "PUSH: client does not support TLS Keying Material "
+"Exporters but --force-tls-key-material-export is enabled.");
+auth_set_client_reason(tls_multi, "Client incompatible with this "
+ "server. Keying Material Exporters (RFC 5705) "
+ "support missing. Upgrade to a client that "
+ "supports this feature (OpenVPN 2.6.0+).");
+return false;
+}
if (proto & IV_PROTO_DYN_TLS_CRYPT)
{
o->imported_protocol_flags |= CO_USE_DYNAMIC_TLS_CRYPT;
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index e498114..1b28a19 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1561,6 +1561,7 @@
SHOW_STR(auth_user_pass_verify_script);
SHOW_BOOL(auth_user_pass_verify_script_via_file);
SHOW_BOOL(auth_token_generate);
+SHOW_BOOL(force_key_material_export);
SHOW_INT(auth_token_lifetime);
SHOW_STR_INLINE(auth_token_secret_file);
#if PORT_SHARE
@@ -2802,6 +2803,11 @@
{
msg(M_USAGE, "--vlan-tagging requires --mode server");
}
+
+if
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld, plaisthos.
cron2 has posted comments on this change. (
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email )
The change is no longer submittable: Code-Review is unsatisfied now.
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Patch Set 8: Code-Review-2
(2 comments)
Patchset:
PS8:
sorry... found another one :-(
File src/openvpn/crypto.c:
http://gerrit.openvpn.net/c/openvpn/+/460/comment/131b2f38_d4640bad :
PS8, Line 1809: return (ret && memcmp(out, expected_out, sizeof(out)) != 0);
It pains me to return to "-2" again, but there is something really weird going
on here - to see what happens if the PRF fails, I changed "expected_out[3] to
"2" in my tree, and it still succeeds. Wat. So I look at the comparison, and
we should be checking for `== 0` here ("out == expected_out", this is not
strcmp()...).
So I fired up gdb with -O0, and this is what it says...
```
(gdb) print ret
$1 = 1
(gdb) print out
$2 = "qD\376%@su\225"
(gdb) print expected_out
$3 = "\340_\037\001\000\000\000"
```
--
To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email
To unsubscribe, or for help writing mail filters, visit
http://gerrit.openvpn.net/settings
Gerrit-Project: openvpn
Gerrit-Branch: master
Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Gerrit-Change-Number: 460
Gerrit-PatchSet: 8
Gerrit-Owner: plaisthos
Gerrit-Reviewer: cron2
Gerrit-Reviewer: flichtenheld
Gerrit-CC: openvpn-devel
Gerrit-Attention: plaisthos
Gerrit-Attention: flichtenheld
Gerrit-Comment-Date: Wed, 03 Jan 2024 22:45:10 +
Gerrit-HasComments: Yes
Gerrit-Has-Labels: Yes
Gerrit-MessageType: comment
___
Openvpn-devel mailing list
Openvpn-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld, plaisthos. cron2 has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 8: Code-Review+2 (1 comment) Patchset: PS8: Looks good now. Will proceed to send mail and subject this patch to more testing. -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 8 Gerrit-Owner: plaisthos Gerrit-Reviewer: cron2 Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: plaisthos Gerrit-Attention: flichtenheld Gerrit-Comment-Date: Tue, 02 Jan 2024 12:51:26 + Gerrit-HasComments: Yes Gerrit-Has-Labels: Yes Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: cron2, flichtenheld. plaisthos has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 8: (1 comment) File src/openvpn/options.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/b61da8f3_c652d84a : PS7, Line 3650: "forbids it. Connections will only work with peers running " > Here's the location with "... FIPS 140-2)forbids it", missing whitespace. Done -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 8 Gerrit-Owner: plaisthos Gerrit-Reviewer: cron2 Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: cron2 Gerrit-Attention: flichtenheld Gerrit-Comment-Date: Mon, 01 Jan 2024 19:17:22 + Gerrit-HasComments: Yes Gerrit-Has-Labels: No Comment-In-Reply-To: cron2 Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: cron2, flichtenheld.
Hello cron2, flichtenheld,
I'd like you to reexamine a change. Please visit
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email
to look at the new patch set (#8).
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Check PRF availability on initialisation and add --force-tls-key-material-export
We now warn a user if the TLS 1.0 PRF is not supported by the cryptographic
library of the system. Also add the option --force-tls-key-material-export
that automatically rejects clients that do not support TLS Keying Material
Export and automatically enable it when TLS 1.0 PRF support is not available.
Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Signed-off-by: Arne Schwabe
---
M doc/man-sections/protocol-options.rst
M src/openvpn/crypto.c
M src/openvpn/crypto.h
M src/openvpn/multi.c
M src/openvpn/options.c
M src/openvpn/options.h
6 files changed, 83 insertions(+), 0 deletions(-)
git pull ssh://gerrit.openvpn.net:29418/openvpn refs/changes/60/460/8
diff --git a/doc/man-sections/protocol-options.rst
b/doc/man-sections/protocol-options.rst
index 948c0c8..8b061d2 100644
--- a/doc/man-sections/protocol-options.rst
+++ b/doc/man-sections/protocol-options.rst
@@ -242,3 +242,11 @@
a key renegotiation begins (default :code:`3600` seconds). This feature
allows for a graceful transition from old to new key, and removes the key
renegotiation sequence from the critical path of tunnel data forwarding.
+
+--force-tls-key-material-export
+ This option is only available in --mode server and forces to use
+ Keying Material Exporters (RFC 5705) for clients. This can be used to
+ simulate an environment where the cryptographic library does not support
+ the older method to generate data channel keys anymore. This option is
+ intended to be a test option and might be removed in a future OpenVPN
+ version without notice.
diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c
index e4452d7..8c17f2a 100644
--- a/src/openvpn/crypto.c
+++ b/src/openvpn/crypto.c
@@ -1789,3 +1789,22 @@
gc_free();
return ret;
}
+
+bool
+check_tls_prf_working(void)
+{
+/* Modern TLS libraries might no longer support the TLS 1.0 PRF with
+ * MD5+SHA1. This allows us to establish connections only
+ * with other 2.6.0+ OpenVPN peers.
+ * Do a simple dummy test here to see if it works. */
+const char *seed = "tls1-prf-test";
+const char *secret = "tls1-prf-test-secret";
+uint8_t out[8];
+uint8_t expected_out[] = { 0xe0, 0x5f, 0x1f, 1, 0, 0, 0, 0};
+
+int ret = ssl_tls1_PRF((uint8_t *)seed, (int) strlen(seed),
+ (uint8_t *)secret, (int) strlen(secret),
+ out, sizeof(out));
+
+return (ret && memcmp(out, expected_out, sizeof(out)) != 0);
+}
diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h
index 9255d38..4201524 100644
--- a/src/openvpn/crypto.h
+++ b/src/openvpn/crypto.h
@@ -593,4 +593,12 @@
return kt;
}
+/**
+ * Checks if the current TLS library supports the TLS 1.0 PRF with MD5+SHA1
+ * that OpenVPN uses when TLS Keying Material Export is not available.
+ *
+ * @return true if supported, false otherwise.
+ */
+bool check_tls_prf_working(void);
+
#endif /* CRYPTO_H */
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 8b490ed..35e8707 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -1830,6 +1830,16 @@
{
o->imported_protocol_flags |= CO_USE_TLS_KEY_MATERIAL_EXPORT;
}
+else if (o->force_key_material_export)
+{
+msg(M_INFO, "PUSH: client does not support TLS key material export"
+"but --force-tls-key-material-export is enabled.");
+auth_set_client_reason(tls_multi, "Client incompatible with this "
+ "server. Keying Material Exporters (RFC 5705) "
+ "support missing. Upgrade to a client that "
+ "supports this feature (OpenVPN 2.6.0+).");
+return false;
+}
if (proto & IV_PROTO_DYN_TLS_CRYPT)
{
o->imported_protocol_flags |= CO_USE_DYNAMIC_TLS_CRYPT;
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index e498114..1b28a19 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1561,6 +1561,7 @@
SHOW_STR(auth_user_pass_verify_script);
SHOW_BOOL(auth_user_pass_verify_script_via_file);
SHOW_BOOL(auth_token_generate);
+SHOW_BOOL(force_key_material_export);
SHOW_INT(auth_token_lifetime);
SHOW_STR_INLINE(auth_token_secret_file);
#if PORT_SHARE
@@ -2802,6 +2803,11 @@
{
msg(M_USAGE, "--vlan-tagging requires --mode server");
}
+
+if (options->force_key_material_export)
+{
+msg(M_USAGE, "--force-tls-key-material-export requires --mode
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: cron2, flichtenheld. plaisthos has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 7: (2 comments) File src/openvpn/multi.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/e38ba8a4_88fcee07 : PS5, Line 1841: return false; > done for "(RFC 5705)support", not done for "thisserver" (first line). Done File src/openvpn/options.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/d0301600_10b5cb6d : PS5, Line 3649: "by TLS library. Your system does not support this calculation " > the change v5->v7 brought in a new whitespace error here, "(FIPS > 140-2)forbids". Done -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 7 Gerrit-Owner: plaisthos Gerrit-Reviewer: cron2 Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: cron2 Gerrit-Attention: flichtenheld Gerrit-Comment-Date: Mon, 01 Jan 2024 19:04:40 + Gerrit-HasComments: Yes Gerrit-Has-Labels: No Comment-In-Reply-To: plaisthos Comment-In-Reply-To: cron2 Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld, plaisthos. cron2 has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 7: (1 comment) File src/openvpn/options.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/9107bf4d_53ba32a8 : PS7, Line 3650: "forbids it. Connections will only work with peers running " Here's the location with "... FIPS 140-2)forbids it", missing whitespace. -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 7 Gerrit-Owner: plaisthos Gerrit-Reviewer: cron2 Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: plaisthos Gerrit-Attention: flichtenheld Gerrit-Comment-Date: Sat, 30 Dec 2023 16:45:07 + Gerrit-HasComments: Yes Gerrit-Has-Labels: No Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld, plaisthos. cron2 has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 7: Code-Review-2 (2 comments) File src/openvpn/multi.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/336c9224_c681507d : PS5, Line 1841: return false; > Done done for "(RFC 5705)support", not done for "thisserver" (first line). File src/openvpn/options.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/850dc22b_4f3310f4 : PS5, Line 3649: "by TLS library. Your system does not support this calculation " the change v5->v7 brought in a new whitespace error here, "(FIPS 140-2)forbids". -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 7 Gerrit-Owner: plaisthos Gerrit-Reviewer: cron2 Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: plaisthos Gerrit-Attention: flichtenheld Gerrit-Comment-Date: Wed, 13 Dec 2023 17:42:09 + Gerrit-HasComments: Yes Gerrit-Has-Labels: Yes Comment-In-Reply-To: plaisthos Comment-In-Reply-To: cron2 Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: cron2, flichtenheld.
plaisthos has posted comments on this change. (
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email )
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Patch Set 6:
(2 comments)
File src/openvpn/multi.c:
http://gerrit.openvpn.net/c/openvpn/+/460/comment/09e5b596_0004b9ee :
PS5, Line 1841: return false;
> there is whitespace missing at the first and second line wrap ("thisserver"
> and "(RFC 5705)support"
Done
File src/openvpn/options.c:
http://gerrit.openvpn.net/c/openvpn/+/460/comment/4bde8b54_2a323d2b :
PS5, Line 3661: }
> D'oh. Sorry for missing that.
whoops sorry for that. My bash history also shows that I still had the option
on the command line, so I totally missed that.
--
To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email
To unsubscribe, or for help writing mail filters, visit
http://gerrit.openvpn.net/settings
Gerrit-Project: openvpn
Gerrit-Branch: master
Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Gerrit-Change-Number: 460
Gerrit-PatchSet: 6
Gerrit-Owner: plaisthos
Gerrit-Reviewer: cron2
Gerrit-Reviewer: flichtenheld
Gerrit-CC: openvpn-devel
Gerrit-Attention: cron2
Gerrit-Attention: flichtenheld
Gerrit-Comment-Date: Tue, 12 Dec 2023 12:11:27 +
Gerrit-HasComments: Yes
Gerrit-Has-Labels: No
Comment-In-Reply-To: cron2
Comment-In-Reply-To: flichtenheld
Gerrit-MessageType: comment
___
Openvpn-devel mailing list
Openvpn-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: cron2, plaisthos.
Hello cron2, flichtenheld,
I'd like you to reexamine a change. Please visit
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email
to look at the new patch set (#7).
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Check PRF availability on initialisation and add --force-tls-key-material-export
We now warn a user if the TLS 1.0 PRF is not supported by the cryptographic
library of the system. Also add the option --force-tls-key-material-export
that automatically rejects clients that do not support TLS Keying Material
Export and automatically enable it when TLS 1.0 PRF support is not available.
Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Signed-off-by: Arne Schwabe
---
M doc/man-sections/protocol-options.rst
M src/openvpn/crypto.c
M src/openvpn/crypto.h
M src/openvpn/multi.c
M src/openvpn/options.c
M src/openvpn/options.h
6 files changed, 83 insertions(+), 0 deletions(-)
git pull ssh://gerrit.openvpn.net:29418/openvpn refs/changes/60/460/7
diff --git a/doc/man-sections/protocol-options.rst
b/doc/man-sections/protocol-options.rst
index 948c0c8..8b061d2 100644
--- a/doc/man-sections/protocol-options.rst
+++ b/doc/man-sections/protocol-options.rst
@@ -242,3 +242,11 @@
a key renegotiation begins (default :code:`3600` seconds). This feature
allows for a graceful transition from old to new key, and removes the key
renegotiation sequence from the critical path of tunnel data forwarding.
+
+--force-tls-key-material-export
+ This option is only available in --mode server and forces to use
+ Keying Material Exporters (RFC 5705) for clients. This can be used to
+ simulate an environment where the cryptographic library does not support
+ the older method to generate data channel keys anymore. This option is
+ intended to be a test option and might be removed in a future OpenVPN
+ version without notice.
diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c
index e4452d7..8c17f2a 100644
--- a/src/openvpn/crypto.c
+++ b/src/openvpn/crypto.c
@@ -1789,3 +1789,22 @@
gc_free();
return ret;
}
+
+bool
+check_tls_prf_working(void)
+{
+/* Modern TLS libraries might no longer support the TLS 1.0 PRF with
+ * MD5+SHA1. This allows us to establish connections only
+ * with other 2.6.0+ OpenVPN peers.
+ * Do a simple dummy test here to see if it works. */
+const char *seed = "tls1-prf-test";
+const char *secret = "tls1-prf-test-secret";
+uint8_t out[8];
+uint8_t expected_out[] = { 0xe0, 0x5f, 0x1f, 1, 0, 0, 0, 0};
+
+int ret = ssl_tls1_PRF((uint8_t *)seed, (int) strlen(seed),
+ (uint8_t *)secret, (int) strlen(secret),
+ out, sizeof(out));
+
+return (ret && memcmp(out, expected_out, sizeof(out)) != 0);
+}
diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h
index 9255d38..4201524 100644
--- a/src/openvpn/crypto.h
+++ b/src/openvpn/crypto.h
@@ -593,4 +593,12 @@
return kt;
}
+/**
+ * Checks if the current TLS library supports the TLS 1.0 PRF with MD5+SHA1
+ * that OpenVPN uses when TLS Keying Material Export is not available.
+ *
+ * @return true if supported, false otherwise.
+ */
+bool check_tls_prf_working(void);
+
#endif /* CRYPTO_H */
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 8b490ed..e70ad91 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -1830,6 +1830,16 @@
{
o->imported_protocol_flags |= CO_USE_TLS_KEY_MATERIAL_EXPORT;
}
+else if (o->force_key_material_export)
+{
+msg(M_INFO, "PUSH: client does not support TLS key material export"
+"but --force-tls-key-material-export is enabled.");
+auth_set_client_reason(tls_multi, "Client incompatible with this"
+ "server. Keying Material Exporters (RFC 5705) "
+ "support missing. Upgrade to a client that "
+ "supports this feature (OpenVPN 2.6.0+).");
+return false;
+}
if (proto & IV_PROTO_DYN_TLS_CRYPT)
{
o->imported_protocol_flags |= CO_USE_DYNAMIC_TLS_CRYPT;
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 1521872..6f98362 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1561,6 +1561,7 @@
SHOW_STR(auth_user_pass_verify_script);
SHOW_BOOL(auth_user_pass_verify_script_via_file);
SHOW_BOOL(auth_token_generate);
+SHOW_BOOL(force_key_material_export);
SHOW_INT(auth_token_lifetime);
SHOW_STR_INLINE(auth_token_secret_file);
#if PORT_SHARE
@@ -2802,6 +2803,11 @@
{
msg(M_USAGE, "--vlan-tagging requires --mode server");
}
+
+if (options->force_key_material_export)
+{
+msg(M_USAGE, "--force-tls-key-material-export requires --mode
server");
+
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: cron2, plaisthos.
Hello cron2, flichtenheld,
I'd like you to reexamine a change. Please visit
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email
to look at the new patch set (#6).
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Check PRF availability on initialisation and add --force-tls-key-material-export
We now warn a user if the TLS 1.0 PRF is not supported by the cryptographic
library of the system. Also add the option --force-tls-key-material-export
that automatically rejects clients that do not support TLS Keying Material
Export and automatically enable it when TLS 1.0 PRF support is not available.
Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Signed-off-by: Arne Schwabe
---
M doc/man-sections/protocol-options.rst
M src/openvpn/crypto.c
M src/openvpn/crypto.h
M src/openvpn/multi.c
M src/openvpn/options.c
M src/openvpn/options.h
6 files changed, 83 insertions(+), 0 deletions(-)
git pull ssh://gerrit.openvpn.net:29418/openvpn refs/changes/60/460/6
diff --git a/doc/man-sections/protocol-options.rst
b/doc/man-sections/protocol-options.rst
index 948c0c8..8b061d2 100644
--- a/doc/man-sections/protocol-options.rst
+++ b/doc/man-sections/protocol-options.rst
@@ -242,3 +242,11 @@
a key renegotiation begins (default :code:`3600` seconds). This feature
allows for a graceful transition from old to new key, and removes the key
renegotiation sequence from the critical path of tunnel data forwarding.
+
+--force-tls-key-material-export
+ This option is only available in --mode server and forces to use
+ Keying Material Exporters (RFC 5705) for clients. This can be used to
+ simulate an environment where the cryptographic library does not support
+ the older method to generate data channel keys anymore. This option is
+ intended to be a test option and might be removed in a future OpenVPN
+ version without notice.
diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c
index e4452d7..8c17f2a 100644
--- a/src/openvpn/crypto.c
+++ b/src/openvpn/crypto.c
@@ -1789,3 +1789,22 @@
gc_free();
return ret;
}
+
+bool
+check_tls_prf_working(void)
+{
+/* Modern TLS libraries might no longer support the TLS 1.0 PRF with
+ * MD5+SHA1. This allows us to establish connections only
+ * with other 2.6.0+ OpenVPN peers.
+ * Do a simple dummy test here to see if it works. */
+const char *seed = "tls1-prf-test";
+const char *secret = "tls1-prf-test-secret";
+uint8_t out[8];
+uint8_t expected_out[] = { 0xe0, 0x5f, 0x1f, 1, 0, 0, 0, 0};
+
+int ret = ssl_tls1_PRF((uint8_t *)seed, (int) strlen(seed),
+ (uint8_t *)secret, (int) strlen(secret),
+ out, sizeof(out));
+
+return (ret && memcmp(out, expected_out, sizeof(out)) != 0);
+}
diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h
index 9255d38..4201524 100644
--- a/src/openvpn/crypto.h
+++ b/src/openvpn/crypto.h
@@ -593,4 +593,12 @@
return kt;
}
+/**
+ * Checks if the current TLS library supports the TLS 1.0 PRF with MD5+SHA1
+ * that OpenVPN uses when TLS Keying Material Export is not available.
+ *
+ * @return true if supported, false otherwise.
+ */
+bool check_tls_prf_working(void);
+
#endif /* CRYPTO_H */
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 8b490ed..82122f5 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -1830,6 +1830,16 @@
{
o->imported_protocol_flags |= CO_USE_TLS_KEY_MATERIAL_EXPORT;
}
+else if (o->force_key_material_export)
+{
+msg(M_INFO, "PUSH: client does not support TLS key material export"
+"but --force-tls-key-material-export is enabled.");
+auth_set_client_reason(tls_multi, "Client incompatible with this"
+ "server. Keying Material Exporters (RFC 5705)"
+ "support missing. Upgrade to a client that "
+ "supports this feature (OpenVPN 2.6.0+).");
+return false;
+}
if (proto & IV_PROTO_DYN_TLS_CRYPT)
{
o->imported_protocol_flags |= CO_USE_DYNAMIC_TLS_CRYPT;
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 1521872..6f98362 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1561,6 +1561,7 @@
SHOW_STR(auth_user_pass_verify_script);
SHOW_BOOL(auth_user_pass_verify_script_via_file);
SHOW_BOOL(auth_token_generate);
+SHOW_BOOL(force_key_material_export);
SHOW_INT(auth_token_lifetime);
SHOW_STR_INLINE(auth_token_secret_file);
#if PORT_SHARE
@@ -2802,6 +2803,11 @@
{
msg(M_USAGE, "--vlan-tagging requires --mode server");
}
+
+if (options->force_key_material_export)
+{
+msg(M_USAGE, "--force-tls-key-material-export requires --mode
server");
+
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: cron2, plaisthos. flichtenheld has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 5: -Code-Review (1 comment) File src/openvpn/options.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/c97bbfa5_d626d157 : PS5, Line 3661: } > I might need new glasses, but as far as I can see, this code does all the > checks, and *claims* to en […] D'oh. Sorry for missing that. -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 5 Gerrit-Owner: plaisthos Gerrit-Reviewer: cron2 Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: plaisthos Gerrit-Attention: cron2 Gerrit-Comment-Date: Tue, 12 Dec 2023 10:41:31 + Gerrit-HasComments: Yes Gerrit-Has-Labels: Yes Comment-In-Reply-To: cron2 Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: plaisthos.
cron2 has posted comments on this change. (
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email )
The change is no longer submittable: Code-Review is unsatisfied now.
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Patch Set 5: Code-Review-2
(3 comments)
Patchset:
PS5:
feature-ack, but the code is not fully there yet
File src/openvpn/multi.c:
http://gerrit.openvpn.net/c/openvpn/+/460/comment/a893a87b_2e6a6e2a :
PS5, Line 1841: return false;
there is whitespace missing at the first and second line wrap ("thisserver" and
"(RFC 5705)support"
File src/openvpn/options.c:
http://gerrit.openvpn.net/c/openvpn/+/460/comment/34f227b9_5a68d2c6 :
PS5, Line 3661: }
I might need new glasses, but as far as I can see, this code does all the
checks, and *claims* to enable the option - but the only place I can see where
the option is actually turned on is "if it's passed on the command line"...?
--
To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email
To unsubscribe, or for help writing mail filters, visit
http://gerrit.openvpn.net/settings
Gerrit-Project: openvpn
Gerrit-Branch: master
Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Gerrit-Change-Number: 460
Gerrit-PatchSet: 5
Gerrit-Owner: plaisthos
Gerrit-Reviewer: cron2
Gerrit-Reviewer: flichtenheld
Gerrit-CC: openvpn-devel
Gerrit-Attention: plaisthos
Gerrit-Comment-Date: Tue, 12 Dec 2023 07:33:13 +
Gerrit-HasComments: Yes
Gerrit-Has-Labels: Yes
Gerrit-MessageType: comment
___
Openvpn-devel mailing list
Openvpn-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: plaisthos. flichtenheld has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 5: Code-Review+2 -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 5 Gerrit-Owner: plaisthos Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: plaisthos Gerrit-Comment-Date: Fri, 08 Dec 2023 11:07:46 + Gerrit-HasComments: No Gerrit-Has-Labels: Yes Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld.
Hello flichtenheld,
I'd like you to reexamine a change. Please visit
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email
to look at the new patch set (#5).
The following approvals got outdated and were removed:
Code-Review-1 by flichtenheld
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Check PRF availability on initialisation and add --force-tls-key-material-export
We now warn a user if the TLS 1.0 PRF is not supported by the cryptographic
library of the system. Also add the option --force-tls-key-material-export
that automatically rejects clients that do not support TLS Keying Material
Export and automatically enable it when TLS 1.0 PRF support is not available.
Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Signed-off-by: Arne Schwabe
---
M doc/man-sections/protocol-options.rst
M src/openvpn/crypto.c
M src/openvpn/crypto.h
M src/openvpn/multi.c
M src/openvpn/options.c
M src/openvpn/options.h
6 files changed, 83 insertions(+), 0 deletions(-)
git pull ssh://gerrit.openvpn.net:29418/openvpn refs/changes/60/460/5
diff --git a/doc/man-sections/protocol-options.rst
b/doc/man-sections/protocol-options.rst
index 948c0c8..8b061d2 100644
--- a/doc/man-sections/protocol-options.rst
+++ b/doc/man-sections/protocol-options.rst
@@ -242,3 +242,11 @@
a key renegotiation begins (default :code:`3600` seconds). This feature
allows for a graceful transition from old to new key, and removes the key
renegotiation sequence from the critical path of tunnel data forwarding.
+
+--force-tls-key-material-export
+ This option is only available in --mode server and forces to use
+ Keying Material Exporters (RFC 5705) for clients. This can be used to
+ simulate an environment where the cryptographic library does not support
+ the older method to generate data channel keys anymore. This option is
+ intended to be a test option and might be removed in a future OpenVPN
+ version without notice.
diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c
index e4452d7..8c17f2a 100644
--- a/src/openvpn/crypto.c
+++ b/src/openvpn/crypto.c
@@ -1789,3 +1789,22 @@
gc_free();
return ret;
}
+
+bool
+check_tls_prf_working(void)
+{
+/* Modern TLS libraries might no longer support the TLS 1.0 PRF with
+ * MD5+SHA1. This allows us to establish connections only
+ * with other 2.6.0+ OpenVPN peers.
+ * Do a simple dummy test here to see if it works. */
+const char *seed = "tls1-prf-test";
+const char *secret = "tls1-prf-test-secret";
+uint8_t out[8];
+uint8_t expected_out[] = { 0xe0, 0x5f, 0x1f, 1, 0, 0, 0, 0};
+
+int ret = ssl_tls1_PRF((uint8_t *)seed, (int) strlen(seed),
+ (uint8_t *)secret, (int) strlen(secret),
+ out, sizeof(out));
+
+return (ret && memcmp(out, expected_out, sizeof(out)) != 0);
+}
diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h
index 9255d38..4201524 100644
--- a/src/openvpn/crypto.h
+++ b/src/openvpn/crypto.h
@@ -593,4 +593,12 @@
return kt;
}
+/**
+ * Checks if the current TLS library supports the TLS 1.0 PRF with MD5+SHA1
+ * that OpenVPN uses when TLS Keying Material Export is not available.
+ *
+ * @return true if supported, false otherwise.
+ */
+bool check_tls_prf_working(void);
+
#endif /* CRYPTO_H */
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 8b490ed..82122f5 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -1830,6 +1830,16 @@
{
o->imported_protocol_flags |= CO_USE_TLS_KEY_MATERIAL_EXPORT;
}
+else if (o->force_key_material_export)
+{
+msg(M_INFO, "PUSH: client does not support TLS key material export"
+"but --force-tls-key-material-export is enabled.");
+auth_set_client_reason(tls_multi, "Client incompatible with this"
+ "server. Keying Material Exporters (RFC 5705)"
+ "support missing. Upgrade to a client that "
+ "supports this feature (OpenVPN 2.6.0+).");
+return false;
+}
if (proto & IV_PROTO_DYN_TLS_CRYPT)
{
o->imported_protocol_flags |= CO_USE_DYNAMIC_TLS_CRYPT;
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 1521872..fc0a5d5 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1561,6 +1561,7 @@
SHOW_STR(auth_user_pass_verify_script);
SHOW_BOOL(auth_user_pass_verify_script_via_file);
SHOW_BOOL(auth_token_generate);
+SHOW_BOOL(force_key_material_export);
SHOW_INT(auth_token_lifetime);
SHOW_STR_INLINE(auth_token_secret_file);
#if PORT_SHARE
@@ -2802,6 +2803,11 @@
{
msg(M_USAGE, "--vlan-tagging requires --mode server");
}
+
+if (options->force_key_material_export)
+{
+
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld. plaisthos has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 4: (1 comment) File src/openvpn/crypto.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/e88d1a14_0f492b72 : PS3, Line 1797: * limits our compatibility to other 2.6.x+ OperVPN peers. Do a simple > I think my problem is "limits our compatibility to". I find it difficult to > parse that correctly. […] Acknowledged -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 4 Gerrit-Owner: plaisthos Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: flichtenheld Gerrit-Comment-Date: Thu, 07 Dec 2023 18:25:34 + Gerrit-HasComments: Yes Gerrit-Has-Labels: No Comment-In-Reply-To: plaisthos Comment-In-Reply-To: flichtenheld Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: plaisthos. flichtenheld has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 4: Code-Review-1 (1 comment) File src/openvpn/crypto.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/8d18aa2f_604e3d4b : PS3, Line 1797: * limits our compatibility to other 2.6.x+ OperVPN peers. Do a simple > limits in the sense that we are limited to only 2.6.0+ peers. […] I think my problem is "limits our compatibility to". I find it difficult to parse that correctly. May I suggest to drop that? "This only allows us to establish connections with peers that support keying material export (e.g. OpenVPN 2.6.0+)." -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 4 Gerrit-Owner: plaisthos Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: plaisthos Gerrit-Comment-Date: Fri, 01 Dec 2023 12:28:54 + Gerrit-HasComments: Yes Gerrit-Has-Labels: Yes Comment-In-Reply-To: plaisthos Comment-In-Reply-To: flichtenheld Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld.
Hello flichtenheld,
I'd like you to reexamine a change. Please visit
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email
to look at the new patch set (#4).
The following approvals got outdated and were removed:
Code-Review-1 by flichtenheld
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Check PRF availability on initialisation and add --force-tls-key-material-export
We now warn a user if the TLS 1.0 PRF is not supported by the cryptographic
library of the system. Also add the option --force-tls-key-material-export
that automatically rejects clients that do not support TLS Keying Material
Export and automatically enable it when TLS 1.0 PRF support is not available.
Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Signed-off-by: Arne Schwabe
---
M doc/man-sections/protocol-options.rst
M src/openvpn/crypto.c
M src/openvpn/crypto.h
M src/openvpn/multi.c
M src/openvpn/options.c
M src/openvpn/options.h
6 files changed, 83 insertions(+), 0 deletions(-)
git pull ssh://gerrit.openvpn.net:29418/openvpn refs/changes/60/460/4
diff --git a/doc/man-sections/protocol-options.rst
b/doc/man-sections/protocol-options.rst
index 948c0c8..8b061d2 100644
--- a/doc/man-sections/protocol-options.rst
+++ b/doc/man-sections/protocol-options.rst
@@ -242,3 +242,11 @@
a key renegotiation begins (default :code:`3600` seconds). This feature
allows for a graceful transition from old to new key, and removes the key
renegotiation sequence from the critical path of tunnel data forwarding.
+
+--force-tls-key-material-export
+ This option is only available in --mode server and forces to use
+ Keying Material Exporters (RFC 5705) for clients. This can be used to
+ simulate an environment where the cryptographic library does not support
+ the older method to generate data channel keys anymore. This option is
+ intended to be a test option and might be removed in a future OpenVPN
+ version without notice.
diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c
index e4452d7..3c91fda 100644
--- a/src/openvpn/crypto.c
+++ b/src/openvpn/crypto.c
@@ -1789,3 +1789,22 @@
gc_free();
return ret;
}
+
+bool
+check_tls_prf_working(void)
+{
+/* Modern TLS libraries might no longer support the TLS 1.0 PRF with
+ * MD5+SHA1. This limits our compatibility to establish connections only
+ * with other 2.6.0+ OpenVPN peers.
+ * Do a simple dummy test here to see if it works. */
+const char *seed = "tls1-prf-test";
+const char *secret = "tls1-prf-test-secret";
+uint8_t out[8];
+uint8_t expected_out[] = { 0xe0, 0x5f, 0x1f, 1, 0, 0, 0, 0};
+
+int ret = ssl_tls1_PRF((uint8_t *)seed, (int) strlen(seed),
+ (uint8_t *)secret, (int) strlen(secret),
+ out, sizeof(out));
+
+return (ret && memcmp(out, expected_out, sizeof(out)) != 0);
+}
diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h
index 9255d38..4201524 100644
--- a/src/openvpn/crypto.h
+++ b/src/openvpn/crypto.h
@@ -593,4 +593,12 @@
return kt;
}
+/**
+ * Checks if the current TLS library supports the TLS 1.0 PRF with MD5+SHA1
+ * that OpenVPN uses when TLS Keying Material Export is not available.
+ *
+ * @return true if supported, false otherwise.
+ */
+bool check_tls_prf_working(void);
+
#endif /* CRYPTO_H */
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 8b490ed..82122f5 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -1830,6 +1830,16 @@
{
o->imported_protocol_flags |= CO_USE_TLS_KEY_MATERIAL_EXPORT;
}
+else if (o->force_key_material_export)
+{
+msg(M_INFO, "PUSH: client does not support TLS key material export"
+"but --force-tls-key-material-export is enabled.");
+auth_set_client_reason(tls_multi, "Client incompatible with this"
+ "server. Keying Material Exporters (RFC 5705)"
+ "support missing. Upgrade to a client that "
+ "supports this feature (OpenVPN 2.6.0+).");
+return false;
+}
if (proto & IV_PROTO_DYN_TLS_CRYPT)
{
o->imported_protocol_flags |= CO_USE_DYNAMIC_TLS_CRYPT;
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 2594b66..df49531 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1564,6 +1564,7 @@
SHOW_STR(auth_user_pass_verify_script);
SHOW_BOOL(auth_user_pass_verify_script_via_file);
SHOW_BOOL(auth_token_generate);
+SHOW_BOOL(force_key_material_export);
SHOW_INT(auth_token_lifetime);
SHOW_STR_INLINE(auth_token_secret_file);
#if PORT_SHARE
@@ -2806,6 +2807,11 @@
{
msg(M_USAGE, "--vlan-tagging requires --mode server");
}
+
+if (options->force_key_material_export)
+
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld. plaisthos has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 3: (2 comments) File src/openvpn/crypto.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/25274dc5_732e6f85 : PS1, Line 1797: * limits our compatibility to other 2.6.x+ OpernVPN peers. Do a simple > Not done Now really done File src/openvpn/crypto.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/5cda2246_a787261c : PS3, Line 1797: * limits our compatibility to other 2.6.x+ OperVPN peers. Do a simple > Also, shouldn't that be "pre-2.6.0 peers" instead of "2.6. […] limits in the sense that we are limited to only 2.6.0+ peers. I will adjust the text to make a it a bit more clear. -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 3 Gerrit-Owner: plaisthos Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: flichtenheld Gerrit-Comment-Date: Fri, 01 Dec 2023 12:13:28 + Gerrit-HasComments: Yes Gerrit-Has-Labels: No Comment-In-Reply-To: plaisthos Comment-In-Reply-To: flichtenheld Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: plaisthos. flichtenheld has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 3: Code-Review-1 (2 comments) File src/openvpn/crypto.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/b5d3ee6a_2c915e28 : PS1, Line 1797: * limits our compatibility to other 2.6.x+ OpernVPN peers. Do a simple > Done Not done File src/openvpn/crypto.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/ca315396_343fe5a4 : PS3, Line 1797: * limits our compatibility to other 2.6.x+ OperVPN peers. Do a simple Also, shouldn't that be "pre-2.6.0 peers" instead of "2.6.x+ peers"? -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 3 Gerrit-Owner: plaisthos Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: plaisthos Gerrit-Comment-Date: Fri, 01 Dec 2023 11:06:19 + Gerrit-HasComments: Yes Gerrit-Has-Labels: Yes Comment-In-Reply-To: plaisthos Comment-In-Reply-To: flichtenheld Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld.
Hello flichtenheld,
I'd like you to reexamine a change. Please visit
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email
to look at the new patch set (#2).
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Check PRF availability on initialisation and add --force-tls-key-material-export
We now warn a user if the TLS 1.0 PRF is not supported by the cryptographic
library of the system. Also add the option --force-tls-key-material-export
that automatically rejects clients that do not support TLS Keying Material
Export and automatically enable it when TLS 1.0 PRF support is not available.
Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Signed-off-by: Arne Schwabe
---
M doc/man-sections/protocol-options.rst
M src/openvpn/crypto.c
M src/openvpn/crypto.h
M src/openvpn/multi.c
M src/openvpn/options.c
M src/openvpn/options.h
6 files changed, 82 insertions(+), 0 deletions(-)
git pull ssh://gerrit.openvpn.net:29418/openvpn refs/changes/60/460/2
diff --git a/doc/man-sections/protocol-options.rst
b/doc/man-sections/protocol-options.rst
index 948c0c8..8b061d2 100644
--- a/doc/man-sections/protocol-options.rst
+++ b/doc/man-sections/protocol-options.rst
@@ -242,3 +242,11 @@
a key renegotiation begins (default :code:`3600` seconds). This feature
allows for a graceful transition from old to new key, and removes the key
renegotiation sequence from the critical path of tunnel data forwarding.
+
+--force-tls-key-material-export
+ This option is only available in --mode server and forces to use
+ Keying Material Exporters (RFC 5705) for clients. This can be used to
+ simulate an environment where the cryptographic library does not support
+ the older method to generate data channel keys anymore. This option is
+ intended to be a test option and might be removed in a future OpenVPN
+ version without notice.
diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c
index e4452d7..eb40d90 100644
--- a/src/openvpn/crypto.c
+++ b/src/openvpn/crypto.c
@@ -1789,3 +1789,21 @@
gc_free();
return ret;
}
+
+bool
+check_tls_prf_working(void)
+{
+/* Modern TLS libraries might no longer support the TLS 1.0 PRF. This
+ * limits our compatibility to other 2.6.x+ OperVPN peers. Do a simple
+ * dummy test here to see if it works. */
+const char *seed = "tls1-prf-test";
+const char *secret = "tls1-prf-test-secret";
+uint8_t out[8];
+uint8_t expected_out[] = { 0xe0, 0x5f, 0x1f, 1, 0, 0, 0, 0};
+
+int ret = ssl_tls1_PRF((uint8_t *)seed, (int) strlen(seed),
+ (uint8_t *)secret, (int) strlen(secret),
+ out, sizeof(out));
+
+return (ret && memcmp(out, expected_out, sizeof(out)) != 0);
+}
diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h
index 9255d38..4201524 100644
--- a/src/openvpn/crypto.h
+++ b/src/openvpn/crypto.h
@@ -593,4 +593,12 @@
return kt;
}
+/**
+ * Checks if the current TLS library supports the TLS 1.0 PRF with MD5+SHA1
+ * that OpenVPN uses when TLS Keying Material Export is not available.
+ *
+ * @return true if supported, false otherwise.
+ */
+bool check_tls_prf_working(void);
+
#endif /* CRYPTO_H */
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 8b490ed..82122f5 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -1830,6 +1830,16 @@
{
o->imported_protocol_flags |= CO_USE_TLS_KEY_MATERIAL_EXPORT;
}
+else if (o->force_key_material_export)
+{
+msg(M_INFO, "PUSH: client does not support TLS key material export"
+"but --force-tls-key-material-export is enabled.");
+auth_set_client_reason(tls_multi, "Client incompatible with this"
+ "server. Keying Material Exporters (RFC 5705)"
+ "support missing. Upgrade to a client that "
+ "supports this feature (OpenVPN 2.6.0+).");
+return false;
+}
if (proto & IV_PROTO_DYN_TLS_CRYPT)
{
o->imported_protocol_flags |= CO_USE_DYNAMIC_TLS_CRYPT;
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 2594b66..df49531 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1564,6 +1564,7 @@
SHOW_STR(auth_user_pass_verify_script);
SHOW_BOOL(auth_user_pass_verify_script_via_file);
SHOW_BOOL(auth_token_generate);
+SHOW_BOOL(force_key_material_export);
SHOW_INT(auth_token_lifetime);
SHOW_STR_INLINE(auth_token_secret_file);
#if PORT_SHARE
@@ -2806,6 +2807,11 @@
{
msg(M_USAGE, "--vlan-tagging requires --mode server");
}
+
+if (options->force_key_material_export)
+{
+msg(M_USAGE, "--force-tls-key-material-export requires --mode
server");
+}
}
/*
@@ -3639,6 +3645,30 @@
}
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld. plaisthos has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 1: (2 comments) File src/openvpn/crypto.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/cbdb8303_d315f0e5 : PS1, Line 1797: * limits our compatibility to other 2.6.x+ OpernVPN peers. Do a simple > "OpenVPN" Done File src/openvpn/options.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/ba9c2025_db846721 : PS1, Line 2583: if (options->force_key_material_export) > This is in "if (options->mode == MODE_SERVER)" which is wrong. Done -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 1 Gerrit-Owner: plaisthos Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: flichtenheld Gerrit-Comment-Date: Tue, 28 Nov 2023 13:39:57 + Gerrit-HasComments: Yes Gerrit-Has-Labels: No Comment-In-Reply-To: flichtenheld Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: plaisthos. flichtenheld has posted comments on this change. ( http://gerrit.openvpn.net/c/openvpn/+/460?usp=email ) Change subject: Check PRF availability on initialisation and add --force-tls-key-material-export .. Patch Set 1: Code-Review-2 (2 comments) File src/openvpn/crypto.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/2a674c0e_9a4fdc16 : PS1, Line 1797: * limits our compatibility to other 2.6.x+ OpernVPN peers. Do a simple "OpenVPN" File src/openvpn/options.c: http://gerrit.openvpn.net/c/openvpn/+/460/comment/d4124e62_ecf20def : PS1, Line 2583: if (options->force_key_material_export) This is in "if (options->mode == MODE_SERVER)" which is wrong. -- To view, visit http://gerrit.openvpn.net/c/openvpn/+/460?usp=email To unsubscribe, or for help writing mail filters, visit http://gerrit.openvpn.net/settings Gerrit-Project: openvpn Gerrit-Branch: master Gerrit-Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70 Gerrit-Change-Number: 460 Gerrit-PatchSet: 1 Gerrit-Owner: plaisthos Gerrit-Reviewer: flichtenheld Gerrit-CC: openvpn-devel Gerrit-Attention: plaisthos Gerrit-Comment-Date: Tue, 28 Nov 2023 11:21:56 + Gerrit-HasComments: Yes Gerrit-Has-Labels: Yes Gerrit-MessageType: comment ___ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
[Openvpn-devel] [M] Change in openvpn[master]: Check PRF availability on initialisation and add --force-tls-key-mate...
Attention is currently required from: flichtenheld.
Hello flichtenheld,
I'd like you to do a code review.
Please visit
http://gerrit.openvpn.net/c/openvpn/+/460?usp=email
to review the following change.
Change subject: Check PRF availability on initialisation and add
--force-tls-key-material-export
..
Check PRF availability on initialisation and add --force-tls-key-material-export
We now warn a user if the TLS 1.0 PRF is not supported by the cryptographic
library of the system. Also add the option --force-tls-key-material-export
that automatically rejects clients that do not support TLS Keying Material
Export and automatically enable it when TLS 1.0 PRF support is not available.
Change-Id: I04f8c7c413e7cb62c726262feee6ca89c7e86c70
Signed-off-by: Arne Schwabe
---
M doc/man-sections/protocol-options.rst
M src/openvpn/crypto.c
M src/openvpn/crypto.h
M src/openvpn/multi.c
M src/openvpn/options.c
M src/openvpn/options.h
6 files changed, 81 insertions(+), 0 deletions(-)
git pull ssh://gerrit.openvpn.net:29418/openvpn refs/changes/60/460/1
diff --git a/doc/man-sections/protocol-options.rst
b/doc/man-sections/protocol-options.rst
index 948c0c8..8b061d2 100644
--- a/doc/man-sections/protocol-options.rst
+++ b/doc/man-sections/protocol-options.rst
@@ -242,3 +242,11 @@
a key renegotiation begins (default :code:`3600` seconds). This feature
allows for a graceful transition from old to new key, and removes the key
renegotiation sequence from the critical path of tunnel data forwarding.
+
+--force-tls-key-material-export
+ This option is only available in --mode server and forces to use
+ Keying Material Exporters (RFC 5705) for clients. This can be used to
+ simulate an environment where the cryptographic library does not support
+ the older method to generate data channel keys anymore. This option is
+ intended to be a test option and might be removed in a future OpenVPN
+ version without notice.
diff --git a/src/openvpn/crypto.c b/src/openvpn/crypto.c
index e4452d7..9667c74 100644
--- a/src/openvpn/crypto.c
+++ b/src/openvpn/crypto.c
@@ -1789,3 +1789,21 @@
gc_free();
return ret;
}
+
+bool
+check_tls_prf_working(void)
+{
+/* Modern TLS libraries might no longer support the TLS 1.0 PRF. This
+ * limits our compatibility to other 2.6.x+ OpernVPN peers. Do a simple
+ * dummy test here to see if it works. */
+const char *seed = "tls1-prf-test";
+const char *secret = "tls1-prf-test-secret";
+uint8_t out[8];
+uint8_t expected_out[] = { 0xe0, 0x5f, 0x1f, 1, 0, 0, 0, 0};
+
+int ret = ssl_tls1_PRF((uint8_t *)seed, strlen(seed),
+ (uint8_t *)secret, strlen(secret),
+ out, sizeof(out));
+
+return (ret && memcmp(out, expected_out, sizeof(out)) != 0);
+}
diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h
index 9255d38..4201524 100644
--- a/src/openvpn/crypto.h
+++ b/src/openvpn/crypto.h
@@ -593,4 +593,12 @@
return kt;
}
+/**
+ * Checks if the current TLS library supports the TLS 1.0 PRF with MD5+SHA1
+ * that OpenVPN uses when TLS Keying Material Export is not available.
+ *
+ * @return true if supported, false otherwise.
+ */
+bool check_tls_prf_working(void);
+
#endif /* CRYPTO_H */
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 8b490ed..82122f5 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -1830,6 +1830,16 @@
{
o->imported_protocol_flags |= CO_USE_TLS_KEY_MATERIAL_EXPORT;
}
+else if (o->force_key_material_export)
+{
+msg(M_INFO, "PUSH: client does not support TLS key material export"
+"but --force-tls-key-material-export is enabled.");
+auth_set_client_reason(tls_multi, "Client incompatible with this"
+ "server. Keying Material Exporters (RFC 5705)"
+ "support missing. Upgrade to a client that "
+ "supports this feature (OpenVPN 2.6.0+).");
+return false;
+}
if (proto & IV_PROTO_DYN_TLS_CRYPT)
{
o->imported_protocol_flags |= CO_USE_DYNAMIC_TLS_CRYPT;
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 2594b66..170d5c7 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1564,6 +1564,7 @@
SHOW_STR(auth_user_pass_verify_script);
SHOW_BOOL(auth_user_pass_verify_script_via_file);
SHOW_BOOL(auth_token_generate);
+SHOW_BOOL(force_key_material_export);
SHOW_INT(auth_token_lifetime);
SHOW_STR_INLINE(auth_token_secret_file);
#if PORT_SHARE
@@ -2579,6 +2580,10 @@
{
msg(M_USAGE, "--mode server requires --tls-server");
}
+if (options->force_key_material_export)
+{
+msg(M_USAGE, "--force-tls-key-material-export requires --mode
server");
+}
if (ce->remote)
{
msg(M_USAGE,
