[PATCH v4 1/8] binman: ti-secure: Add support for firewalling entities
Manorit Chawdhry
m-chawdhry at ti.com
Wed Oct 11 08:24:58 CEST 2023
We can now firewall entities while loading them through our secure
entity TIFS, the required information should be present in the
certificate that is being parsed by TIFS.
The following commit adds the support to enable the certificates to be
generated if the firewall configurations are present in the binman dtsi
nodes.
Signed-off-by: Manorit Chawdhry <m-chawdhry at ti.com>
---
tools/binman/btool/openssl.py | 16 +++++++-
tools/binman/etype/ti_secure.py | 90 +++++++++++++++++++++++++++++++++++++++++
tools/binman/etype/x509_cert.py | 3 +-
3 files changed, 106 insertions(+), 3 deletions(-)
diff --git a/tools/binman/btool/openssl.py b/tools/binman/btool/openssl.py
index aad3b61ae27c..dff439df211f 100644
--- a/tools/binman/btool/openssl.py
+++ b/tools/binman/btool/openssl.py
@@ -82,7 +82,7 @@ imageSize = INTEGER:{len(indata)}
return self.run_cmd(*args)
def x509_cert_sysfw(self, cert_fname, input_fname, key_fname, sw_rev,
- config_fname, req_dist_name_dict):
+ config_fname, req_dist_name_dict, firewall_cert_data):
"""Create a certificate to be booted by system firmware
Args:
@@ -94,6 +94,13 @@ imageSize = INTEGER:{len(indata)}
req_dist_name_dict (dict): Dictionary containing key-value pairs of
req_distinguished_name section extensions, must contain extensions for
C, ST, L, O, OU, CN and emailAddress
+ firewall_cert_data (dict):
+ - auth_in_place (int): The Priv ID for copying as the
+ specific host in firewall protected region
+ - num_firewalls (int): The number of firewalls in the
+ extended certificate
+ - certificate (str): Extended firewall certificate with
+ the information for the firewall configurations.
Returns:
str: Tool output
@@ -121,6 +128,7 @@ basicConstraints = CA:true
1.3.6.1.4.1.294.1.3 = ASN1:SEQUENCE:swrv
1.3.6.1.4.1.294.1.34 = ASN1:SEQUENCE:sysfw_image_integrity
1.3.6.1.4.1.294.1.35 = ASN1:SEQUENCE:sysfw_image_load
+1.3.6.1.4.1.294.1.37 = ASN1:SEQUENCE:firewall
[ swrv ]
swrv = INTEGER:{sw_rev}
@@ -132,7 +140,11 @@ imageSize = INTEGER:{len(indata)}
[ sysfw_image_load ]
destAddr = FORMAT:HEX,OCT:00000000
-authInPlace = INTEGER:2
+authInPlace = INTEGER:{hex(firewall_cert_data['auth_in_place'])}
+
+[ firewall ]
+numFirewallRegions = INTEGER:{firewall_cert_data['num_firewalls']}
+{firewall_cert_data['certificate']}
''', file=outf)
args = ['req', '-new', '-x509', '-key', key_fname, '-nodes',
'-outform', 'DER', '-out', cert_fname, '-config', config_fname,
diff --git a/tools/binman/etype/ti_secure.py b/tools/binman/etype/ti_secure.py
index d939dce57139..76649b07b1b8 100644
--- a/tools/binman/etype/ti_secure.py
+++ b/tools/binman/etype/ti_secure.py
@@ -7,9 +7,40 @@
from binman.entry import EntryArg
from binman.etype.x509_cert import Entry_x509_cert
+from dataclasses import dataclass
from dtoc import fdt_util
+ at dataclass
+class Firewall():
+ id: int
+ region: int
+ control : int
+ permissions: list[hex]
+ start_address: str
+ end_address: str
+
+ def __post_init__(self):
+ for key, val in self.__dict__.items():
+ if val is None:
+ raise Exception(f"{key} can't be None in firewall node")
+
+ def get_certificate(self) -> str:
+ unique_identifier = f"{self.id}{self.region}"
+ cert = f"""
+firewallID{unique_identifier} = INTEGER:{self.id}
+region{unique_identifier} = INTEGER:{self.region}
+control{unique_identifier} = INTEGER:{hex(self.control)}
+nPermissionRegs{unique_identifier} = INTEGER:{len(self.permissions)}
+"""
+ for index, permission in enumerate(self.permissions):
+ cert += f"""permissions{unique_identifier}{index} = INTEGER:{hex(permission)}
+"""
+ cert += f"""startAddress{unique_identifier} = FORMAT:HEX,OCT:{self.start_address:02x}
+endAddress{unique_identifier} = FORMAT:HEX,OCT:{self.end_address:02x}
+"""
+ return cert
+
class Entry_ti_secure(Entry_x509_cert):
"""Entry containing a TI x509 certificate binary
@@ -17,6 +48,11 @@ class Entry_ti_secure(Entry_x509_cert):
- content: List of phandles to entries to sign
- keyfile: Filename of file containing key to sign binary with
- sha: Hash function to be used for signing
+ - auth-in-place: This is an integer field that contains two pieces
+ of information
+ Lower Byte - Remains 0x02 as per our use case
+ ( 0x02: Move the authenticated binary back to the header )
+ Upper Byte - The Host ID of the core owning the firewall
Output files:
- input.<unique_name> - input file passed to openssl
@@ -25,6 +61,35 @@ class Entry_ti_secure(Entry_x509_cert):
- cert.<unique_name> - output file generated by openssl (which is
used as the entry contents)
+ Depending on auth-in-place information in the inputs, we read the
+ firewall nodes that describe the configurations of firewall that TIFS
+ will be doing after reading the certificate.
+
+ The syntax of the firewall nodes are as such:
+
+ firewall-257-0 {
+ id = <257>; /* The ID of the firewall being configured */
+ region = <0>; /* Region number to configure */
+
+ control = /* The control register */
+ <(FWCTRL_EN | FWCTRL_LOCK | FWCTRL_BG | FWCTRL_CACHE)>;
+
+ permissions = /* The permission registers */
+ <((FWPRIVID_ALL << FWPRIVID_SHIFT) |
+ FWPERM_SECURE_PRIV_RWCD |
+ FWPERM_SECURE_USER_RWCD |
+ FWPERM_NON_SECURE_PRIV_RWCD |
+ FWPERM_NON_SECURE_USER_RWCD)>;
+
+ /* More defines can be found in k3-security.h */
+
+ start_address = /* The Start Address of the firewall */
+ <0x0 0x0>;
+ end_address = /* The End Address of the firewall */
+ <0xff 0xffffffff>;
+ };
+
+
openssl signs the provided data, using the TI templated config file and
writes the signature in this entry. This allows verification that the
data is genuine.
@@ -32,11 +97,20 @@ class Entry_ti_secure(Entry_x509_cert):
def __init__(self, section, etype, node):
super().__init__(section, etype, node)
self.openssl = None
+ self.firewall_cert_data: dict = {
+ 'auth_in_place': 0x02,
+ 'num_firewalls': 0,
+ 'certificate': '',
+ }
def ReadNode(self):
super().ReadNode()
self.key_fname = self.GetEntryArgsOrProps([
EntryArg('keyfile', str)], required=True)[0]
+ auth_in_place = fdt_util.GetInt(self._node, 'auth-in-place')
+ if auth_in_place:
+ self.firewall_cert_data['auth_in_place'] = auth_in_place
+ self.ReadFirewallNode()
self.sha = fdt_util.GetInt(self._node, 'sha', 512)
self.req_dist_name = {'C': 'US',
'ST': 'TX',
@@ -46,6 +120,22 @@ class Entry_ti_secure(Entry_x509_cert):
'CN': 'TI Support',
'emailAddress': 'support at ti.com'}
+ def ReadFirewallNode(self):
+ self.firewall_cert_data['certificate'] = ""
+ self.firewall_cert_data['num_firewalls'] = 0
+ for node in self._node.subnodes:
+ if 'firewall' in node.name:
+ firewall = Firewall(
+ fdt_util.GetInt(node, 'id'),
+ fdt_util.GetInt(node, 'region'),
+ fdt_util.GetInt(node, 'control'),
+ fdt_util.GetPhandleList(node, 'permissions'),
+ fdt_util.GetInt64(node, 'start_address'),
+ fdt_util.GetInt64(node, 'end_address'),
+ )
+ self.firewall_cert_data['num_firewalls'] += 1
+ self.firewall_cert_data['certificate'] += firewall.get_certificate()
+
def GetCertificate(self, required):
"""Get the contents of this entry
diff --git a/tools/binman/etype/x509_cert.py b/tools/binman/etype/x509_cert.py
index d028cfe38cd9..9e1cf479023b 100644
--- a/tools/binman/etype/x509_cert.py
+++ b/tools/binman/etype/x509_cert.py
@@ -98,7 +98,8 @@ class Entry_x509_cert(Entry_collection):
key_fname=self.key_fname,
config_fname=config_fname,
sw_rev=self.sw_rev,
- req_dist_name_dict=self.req_dist_name)
+ req_dist_name_dict=self.req_dist_name,
+ firewall_cert_data=self.firewall_cert_data)
elif type == 'rom':
stdout = self.openssl.x509_cert_rom(
cert_fname=output_fname,
--
2.41.0
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