| Message ID | 1570497267-13672-4-git-send-email-nayna@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | powerpc: Enabling IMA arch specific secure boot policies | expand |
Nayna Jain <nayna@linux.ibm.com> writes: > PowerNV systems enables the IMA measurement rules only if the > trusted boot is enabled on the system. That confused me a lot. But the key is the distinction between appraisal rules vs measurement rules, right? I think it would be clearer if it was phrased as a positive statement, eg: On PowerNV systems when trusted boot is enabled, additional IMA rules are enabled to implement measurement. Or something like that. > This patch adds the function to detect if the system has trusted > boot enabled. It would probably help people to briefly explain the difference between secure vs trusted boot. > diff --git a/arch/powerpc/include/asm/secure_boot.h b/arch/powerpc/include/asm/secure_boot.h > index 23d2ef2f1f7b..ecd08515e301 100644 > --- a/arch/powerpc/include/asm/secure_boot.h > +++ b/arch/powerpc/include/asm/secure_boot.h > @@ -12,6 +12,7 @@ > > bool is_powerpc_os_secureboot_enabled(void); > struct device_node *get_powerpc_os_sb_node(void); > +bool is_powerpc_trustedboot_enabled(void); > > #else > > @@ -25,5 +26,10 @@ static inline struct device_node *get_powerpc_os_sb_node(void) > return NULL; > } > > +static inline bool is_powerpc_os_trustedboot_enabled(void) That has an extra "_os" in it. > +{ > + return false; > +} > + > #endif > #endif > diff --git a/arch/powerpc/kernel/secure_boot.c b/arch/powerpc/kernel/secure_boot.c > index 0488dbcab6b9..9d5ac1b39e46 100644 > --- a/arch/powerpc/kernel/secure_boot.c > +++ b/arch/powerpc/kernel/secure_boot.c > @@ -7,6 +7,27 @@ > #include <linux/of.h> > #include <asm/secure_boot.h> > > +static const char * const fwsecureboot_compat[] = { > + "ibm,secureboot-v1", > + "ibm,secureboot-v2", > + NULL, > +}; > + > +static struct device_node *get_powerpc_fw_sb_node(void) > +{ > + struct device_node *node; > + int i; > + > + for (i = 0; i < ARRAY_SIZE(fwsecureboot_compat); ++i) { > + node = of_find_compatible_node(NULL, NULL, > + fwsecureboot_compat[i]); > + if (node) > + return node; > + } > + > + return NULL; > +} You shouldn't need to do that by hand, instead use of_find_matching_node(), eg: static struct device_node *get_powerpc_fw_sb_node(void) { static const struct of_device_id ids[] = { { .compatible = "ibm,secureboot-v1", }, { .compatible = "ibm,secureboot-v2", }, {}, }; return of_find_matching_node(NULL, ids); } > @@ -40,3 +61,17 @@ bool is_powerpc_os_secureboot_enabled(void) > pr_info("secureboot mode disabled\n"); > return false; > } > + > +bool is_powerpc_trustedboot_enabled(void) > +{ > + struct device_node *node; > + > + node = get_powerpc_fw_sb_node(); > + if (node && (of_find_property(node, "trusted-enabled", NULL))) { Again this can use of_property_read_bool(), which copes with a NULL node also, so just: + if (of_property_read_bool(node, "trusted-enabled"))) { > + pr_info("trustedboot mode enabled\n"); > + return true; > + } > + > + pr_info("trustedboot mode disabled\n"); > + return false; > +} > -- > 2.20.1 cheers
diff --git a/arch/powerpc/include/asm/secure_boot.h b/arch/powerpc/include/asm/secure_boot.h index 23d2ef2f1f7b..ecd08515e301 100644 --- a/arch/powerpc/include/asm/secure_boot.h +++ b/arch/powerpc/include/asm/secure_boot.h @@ -12,6 +12,7 @@ bool is_powerpc_os_secureboot_enabled(void); struct device_node *get_powerpc_os_sb_node(void); +bool is_powerpc_trustedboot_enabled(void); #else @@ -25,5 +26,10 @@ static inline struct device_node *get_powerpc_os_sb_node(void) return NULL; } +static inline bool is_powerpc_os_trustedboot_enabled(void) +{ + return false; +} + #endif #endif diff --git a/arch/powerpc/kernel/secure_boot.c b/arch/powerpc/kernel/secure_boot.c index 0488dbcab6b9..9d5ac1b39e46 100644 --- a/arch/powerpc/kernel/secure_boot.c +++ b/arch/powerpc/kernel/secure_boot.c @@ -7,6 +7,27 @@ #include <linux/of.h> #include <asm/secure_boot.h> +static const char * const fwsecureboot_compat[] = { + "ibm,secureboot-v1", + "ibm,secureboot-v2", + NULL, +}; + +static struct device_node *get_powerpc_fw_sb_node(void) +{ + struct device_node *node; + int i; + + for (i = 0; i < ARRAY_SIZE(fwsecureboot_compat); ++i) { + node = of_find_compatible_node(NULL, NULL, + fwsecureboot_compat[i]); + if (node) + return node; + } + + return NULL; +} + struct device_node *get_powerpc_os_sb_node(void) { return of_find_compatible_node(NULL, NULL, "ibm,secvar-v1"); @@ -40,3 +61,17 @@ bool is_powerpc_os_secureboot_enabled(void) pr_info("secureboot mode disabled\n"); return false; } + +bool is_powerpc_trustedboot_enabled(void) +{ + struct device_node *node; + + node = get_powerpc_fw_sb_node(); + if (node && (of_find_property(node, "trusted-enabled", NULL))) { + pr_info("trustedboot mode enabled\n"); + return true; + } + + pr_info("trustedboot mode disabled\n"); + return false; +}
PowerNV systems enables the IMA measurement rules only if the trusted boot is enabled on the system. This patch adds the function to detect if the system has trusted boot enabled. Signed-off-by: Nayna Jain <nayna@linux.ibm.com> --- arch/powerpc/include/asm/secure_boot.h | 6 +++++ arch/powerpc/kernel/secure_boot.c | 35 ++++++++++++++++++++++++++ 2 files changed, 41 insertions(+)