From 8c89386bb130d398ef1ed21c988b804d4a4f4bcd Mon Sep 17 00:00:00 2001 From: Stefan Metzmacher Date: Mon, 21 Feb 2022 23:48:37 +0100 Subject: [PATCH 1/7] s3:py_net: allow machinepass=None to py_net_join_member() BUG: https://bugzilla.samba.org/show_bug.cgi?id=14984 Signed-off-by: Stefan Metzmacher Reviewed-by: Andrew Bartlett Reviewed-by: Andreas Schneider (cherry picked from commit 576bdb08c51c47c390cc390fbefdcfee275b7f0f) --- source3/utils/py_net.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/source3/utils/py_net.c b/source3/utils/py_net.c index 3142f83bc7f7..0d774bcb805d 100644 --- a/source3/utils/py_net.c +++ b/source3/utils/py_net.c @@ -88,7 +88,7 @@ static PyObject *py_net_join_member(py_net_Object *self, PyObject *args, PyObjec return NULL; } - if (!PyArg_ParseTupleAndKeywords(args, kwargs, "|ssssssspp:Join", + if (!PyArg_ParseTupleAndKeywords(args, kwargs, "|sssssszpp:Join", discard_const_p(char *, kwnames), &r->in.dnshostname, &r->in.upn, -- 2.25.1 From bfdfb812b696ee7f1848dc5c5e47ed0625d8f41e Mon Sep 17 00:00:00 2001 From: Stefan Metzmacher Date: Mon, 21 Feb 2022 15:03:22 +0100 Subject: [PATCH 2/7] samba-tool/join_member: let py_net_join_member() choose the password It means we'll let trust_pw_new_value() generate the password. BUG: https://bugzilla.samba.org/show_bug.cgi?id=14984 Signed-off-by: Stefan Metzmacher Reviewed-by: Andrew Bartlett Reviewed-by: Andreas Schneider (cherry picked from commit 59ac782452c4993274fa837256a8b9c5675e707b) --- python/samba/netcmd/domain.py | 2 -- 1 file changed, 2 deletions(-) diff --git a/python/samba/netcmd/domain.py b/python/samba/netcmd/domain.py index 1bdc0ee535a7..e814a47233da 100644 --- a/python/samba/netcmd/domain.py +++ b/python/samba/netcmd/domain.py @@ -691,8 +691,6 @@ class cmd_domain_join(Command): os.rename(f.name, smb_conf) s3_lp = s3param.get_context() s3_lp.load(smb_conf) - if machinepass is None: - machinepass = samba.generate_random_machine_password(14, 40) s3_net = s3_Net(creds, s3_lp, server=server) (sid, domain_name) = s3_net.join_member(netbios_name, machinepass=machinepass, -- 2.25.1 From c023167c11bbde3b08cf2dea082d9dba0f283c73 Mon Sep 17 00:00:00 2001 From: Stefan Metzmacher Date: Mon, 21 Feb 2022 15:08:34 +0100 Subject: [PATCH 3/7] provision: use 120 characters for the dns account password We should use the same as for the computer account. BUG: https://bugzilla.samba.org/show_bug.cgi?id=14984 Signed-off-by: Stefan Metzmacher Reviewed-by: Andrew Bartlett Reviewed-by: Andreas Schneider (cherry picked from commit 3b91be36581de1007427d539daffdaa62752412d) --- python/samba/provision/__init__.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/python/samba/provision/__init__.py b/python/samba/provision/__init__.py index 1723d9935d41..2f513f8383dd 100644 --- a/python/samba/provision/__init__.py +++ b/python/samba/provision/__init__.py @@ -1928,7 +1928,7 @@ def provision_fill(samdb, secrets_ldb, logger, names, paths, if machinepass is None: machinepass = samba.generate_random_machine_password(120, 120) if dnspass is None: - dnspass = samba.generate_random_password(128, 255) + dnspass = samba.generate_random_password(120, 120) samdb.transaction_start() try: -- 2.25.1 From 5ad8ef3b66e578c5fd100d3e4613eaf34d58e5ad Mon Sep 17 00:00:00 2001 From: Stefan Metzmacher Date: Mon, 21 Feb 2022 15:22:06 +0100 Subject: [PATCH 4/7] upgradehelpers.py: let update_machine_account_password() use 120 character passwords We already changed provision to use 120 character passwords with commit 609ca657652862fd9c81fd11f818efb74f72ff55. BUG: https://bugzilla.samba.org/show_bug.cgi?id=14984 Signed-off-by: Stefan Metzmacher Reviewed-by: Andrew Bartlett Reviewed-by: Andreas Schneider (cherry picked from commit 6bb7c0f24918329804b7f4fb71908e8fab99e266) --- python/samba/upgradehelpers.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/python/samba/upgradehelpers.py b/python/samba/upgradehelpers.py index 7f92b45f3fb2..febde7cec401 100644 --- a/python/samba/upgradehelpers.py +++ b/python/samba/upgradehelpers.py @@ -582,7 +582,7 @@ def update_machine_account_password(samdb, secrets_ldb, names): assert(len(res) == 1) msg = ldb.Message(res[0].dn) - machinepass = samba.generate_random_machine_password(128, 255) + machinepass = samba.generate_random_machine_password(120, 120) mputf16 = machinepass.encode('utf-16-le') msg["clearTextPassword"] = ldb.MessageElement(mputf16, ldb.FLAG_MOD_REPLACE, -- 2.25.1 From 90f874a0bf6e06c40b659e14e69a9229ecb2daea Mon Sep 17 00:00:00 2001 From: Stefan Metzmacher Date: Mon, 21 Feb 2022 15:22:50 +0100 Subject: [PATCH 5/7] provision: add a comment that the value of krbtgtpass is ignored in the backend BUG: https://bugzilla.samba.org/show_bug.cgi?id=14984 Signed-off-by: Stefan Metzmacher Reviewed-by: Andrew Bartlett Reviewed-by: Andreas Schneider (cherry picked from commit 725c94d57d3d656bc94633dacbac683a4c11d3e6) --- python/samba/provision/__init__.py | 3 +++ 1 file changed, 3 insertions(+) diff --git a/python/samba/provision/__init__.py b/python/samba/provision/__init__.py index 2f513f8383dd..ff9b8fac916a 100644 --- a/python/samba/provision/__init__.py +++ b/python/samba/provision/__init__.py @@ -1924,6 +1924,9 @@ def provision_fill(samdb, secrets_ldb, logger, names, paths, invocationid = str(uuid.uuid4()) if krbtgtpass is None: + # Note that the machinepass value is ignored + # as the backend (password_hash.c) will generate its + # own random values for the krbtgt keys krbtgtpass = samba.generate_random_machine_password(128, 255) if machinepass is None: machinepass = samba.generate_random_machine_password(120, 120) -- 2.25.1 From 141a386cc1d4a856ecf988fba9fe51edee064e3d Mon Sep 17 00:00:00 2001 From: Stefan Metzmacher Date: Mon, 21 Feb 2022 15:23:54 +0100 Subject: [PATCH 6/7] upgradehelpers.py: add a comment to update_krbtgt_account_password() The backend generates its own random krbtgt password values. BUG: https://bugzilla.samba.org/show_bug.cgi?id=14984 Signed-off-by: Stefan Metzmacher Reviewed-by: Andrew Bartlett Reviewed-by: Andreas Schneider (cherry picked from commit ad0b5561b492dfa28acfc9604b2358bb8b490703) --- python/samba/upgradehelpers.py | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/python/samba/upgradehelpers.py b/python/samba/upgradehelpers.py index febde7cec401..c853668058e7 100644 --- a/python/samba/upgradehelpers.py +++ b/python/samba/upgradehelpers.py @@ -658,9 +658,12 @@ def update_krbtgt_account_password(samdb): assert(len(res) == 1) msg = ldb.Message(res[0].dn) - machinepass = samba.generate_random_machine_password(128, 255) - mputf16 = machinepass.encode('utf-16-le') - msg["clearTextPassword"] = ldb.MessageElement(mputf16, + # Note that the machinepass value is ignored + # as the backend (password_hash.c) will generate its + # own random values for the krbtgt keys + krbtgtpass = samba.generate_random_machine_password(128, 255) + kputf16 = krbtgtpass.encode('utf-16-le') + msg["clearTextPassword"] = ldb.MessageElement(kputf16, ldb.FLAG_MOD_REPLACE, "clearTextPassword") -- 2.25.1 From ed85d5879c1ad0f5b2f914f6bc4bd666b98254c2 Mon Sep 17 00:00:00 2001 From: Stefan Metzmacher Date: Mon, 21 Feb 2022 15:28:53 +0100 Subject: [PATCH 7/7] s3:trusts_utils: use a password length of 120 for machine accounts This is important when we change the machine password against an RODC that proxies the request to an RWDC. An RODC using NetrServerPasswordSet2() to proxy PasswordUpdateForward via NetrLogonSendToSam() ignores a return of NT_STATUS_INVALID_PARAMETER and reports NT_STATUS_OK as result of NetrServerPasswordSet2(). This hopefully found the last hole in our very robust machine account password handling logic inside of trust_pw_change(). The lesson is: try to be as identical to how windows works as possible, everything else may use is untested code paths on Windows. A similar problem was fixed by this commit: commit 609ca657652862fd9c81fd11f818efb74f72ff55 Author: Joseph Sutton Date: Wed Feb 24 02:03:25 2021 +1300 provision: Decrease the length of random machine passwords The current length of 128-255 UTF-16 characters currently causes generation of crypt() passwords to typically fail. This commit decreases the length to 120 UTF-16 characters, which is the same as that used by Windows. BUG: https://bugzilla.samba.org/show_bug.cgi?id=14621 Signed-off-by: Joseph Sutton Reviewed-by: Douglas Bagnall Reviewed-by: Andrew Bartlett BUG: https://bugzilla.samba.org/show_bug.cgi?id=14984 Signed-off-by: Stefan Metzmacher Reviewed-by: Andrew Bartlett Reviewed-by: Andreas Schneider Autobuild-User(master): Stefan Metzmacher Autobuild-Date(master): Wed Feb 23 08:49:54 UTC 2022 on sn-devel-184 (cherry picked from commit 5e2386336c49fab46c1192db972af5da1e916b32) --- source3/libsmb/trusts_util.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/source3/libsmb/trusts_util.c b/source3/libsmb/trusts_util.c index 55e3c74494ab..71e1a35eba7f 100644 --- a/source3/libsmb/trusts_util.c +++ b/source3/libsmb/trusts_util.c @@ -55,10 +55,18 @@ char *trust_pw_new_value(TALLOC_CTX *mem_ctx, int security) { /* - * use secure defaults. + * use secure defaults, which match + * what windows uses for computer passwords. + * + * We used to have min=128 and max=255 here, but + * it's a bad idea because of bugs in the Windows + * RODC/RWDC PasswordUpdateForward handling via + * NetrLogonSendToSam. + * + * See https://bugzilla.samba.org/show_bug.cgi?id=14984 */ - size_t min = 128; - size_t max = 255; + size_t min = 120; + size_t max = 120; switch (sec_channel_type) { case SEC_CHAN_WKSTA: -- 2.25.1