linux-kernel - [RFC 4/9] arm64/cpufeature: detect pointer authentication

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon,  3 Apr 2017 16:19:20 +0100
From:   Mark Rutland <mark.rutland@....com>
To:     linux-arm-kernel@...ts.infradead.org
Cc:     linux-kernel@...r.kernel.org, arnd@...db.de,
        catalin.marinas@....com, christoffer.dall@...aro.org,
        jiong.wang@....com, kvmarm@...ts.cs.columbia.edu,
        linux-arch@...r.kernel.org, marc.zyngier@....com,
        mark.rutland@....com, suzuki.poulose@....com, will.deacon@....com
Subject: [RFC 4/9] arm64/cpufeature: detect pointer authentication

So that we can dynamically handle the presence of pointer authentication
functionality, wire up probing code in cpufeature.c.

Currently, this only detects the presence of an architected algorithm.

Signed-off-by: Mark Rutland <mark.rutland@....com>
Cc: Catalin Marinas <catalin.marinas@....com>
Cc: Suzuki K Poulose <suzuki.poulose@....com>
Cc: Will Deacon <will.deacon@....com>
---
 arch/arm64/include/asm/cpucaps.h |  4 +++-
 arch/arm64/kernel/cpufeature.c   | 22 ++++++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h
index fb78a5d..15dd6d6 100644
--- a/arch/arm64/include/asm/cpucaps.h
+++ b/arch/arm64/include/asm/cpucaps.h
@@ -37,7 +37,9 @@
 #define ARM64_HAS_NO_FPSIMD			16
 #define ARM64_WORKAROUND_REPEAT_TLBI		17
 #define ARM64_WORKAROUND_QCOM_FALKOR_E1003	18
+#define ARM64_HAS_ADDRESS_AUTH			19
+#define ARM64_HAS_GENERIC_AUTH			20
 
-#define ARM64_NCAPS				19
+#define ARM64_NCAPS				21
 
 #endif /* __ASM_CPUCAPS_H */
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 30255b2..172c80e 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -871,6 +871,28 @@ static bool has_no_fpsimd(const struct arm64_cpu_capabilities *entry, int __unus
 		.min_field_value = 0,
 		.matches = has_no_fpsimd,
 	},
+#ifdef CONFIG_ARM64_POINTER_AUTHENTICATION
+	{
+		.desc = "Address authentication (architected algorithm)",
+		.capability = ARM64_HAS_ADDRESS_AUTH,
+		.def_scope = SCOPE_SYSTEM,
+		.sys_reg = SYS_ID_AA64ISAR1_EL1,
+		.sign = FTR_UNSIGNED,
+		.field_pos = ID_AA64ISAR1_APA_SHIFT,
+		.min_field_value = ID_AA64ISAR1_APA_ARCHITECTED,
+		.matches = has_cpuid_feature,
+	},
+	{
+		.desc = "Generic authentication (architected algorithm)",
+		.capability = ARM64_HAS_GENERIC_AUTH,
+		.def_scope = SCOPE_SYSTEM,
+		.sys_reg = SYS_ID_AA64ISAR1_EL1,
+		.sign = FTR_UNSIGNED,
+		.field_pos = ID_AA64ISAR1_GPA_SHIFT,
+		.min_field_value = ID_AA64ISAR1_GPA_ARCHITECTED,
+		.matches = has_cpuid_feature
+	},
+#endif /* CONFIG_ARM64_POINTER_AUTHENTICATION */
 	{},
 };
 
-- 
1.9.1