Fix issues with comments for all the applicable functions to be consistent with kernel-doc format. Move them before the function definition as opposed to the function prototype.
Signed-off-by: Srish Srinivasan <[email protected]> --- arch/powerpc/include/asm/plpks.h | 77 ------ arch/powerpc/platforms/pseries/plpks.c | 328 ++++++++++++++++++++++++- 2 files changed, 318 insertions(+), 87 deletions(-) diff --git a/arch/powerpc/include/asm/plpks.h b/arch/powerpc/include/asm/plpks.h index 7a84069759b0..f303922bf622 100644 --- a/arch/powerpc/include/asm/plpks.h +++ b/arch/powerpc/include/asm/plpks.h @@ -67,122 +67,45 @@ struct plpks_var_name_list { struct plpks_var_name varlist[]; }; -/** - * Updates the authenticated variable. It expects NULL as the component. - */ int plpks_signed_update_var(struct plpks_var *var, u64 flags); -/** - * Writes the specified var and its data to PKS. - * Any caller of PKS driver should present a valid component type for - * their variable. - */ int plpks_write_var(struct plpks_var var); -/** - * Removes the specified var and its data from PKS. - */ int plpks_remove_var(char *component, u8 varos, struct plpks_var_name vname); -/** - * Returns the data for the specified os variable. - * - * Caller must allocate a buffer in var->data with length in var->datalen. - * If no buffer is provided, var->datalen will be populated with the object's - * size. - */ int plpks_read_os_var(struct plpks_var *var); -/** - * Returns the data for the specified firmware variable. - * - * Caller must allocate a buffer in var->data with length in var->datalen. - * If no buffer is provided, var->datalen will be populated with the object's - * size. - */ int plpks_read_fw_var(struct plpks_var *var); -/** - * Returns the data for the specified bootloader variable. - * - * Caller must allocate a buffer in var->data with length in var->datalen. - * If no buffer is provided, var->datalen will be populated with the object's - * size. - */ int plpks_read_bootloader_var(struct plpks_var *var); -/** - * Returns if PKS is available on this LPAR. - */ bool plpks_is_available(void); -/** - * Returns version of the Platform KeyStore. - */ u8 plpks_get_version(void); -/** - * Returns hypervisor storage overhead per object, not including the size of - * the object or label. Only valid for config version >= 2 - */ u16 plpks_get_objoverhead(void); -/** - * Returns maximum password size. Must be >= 32 bytes - */ u16 plpks_get_maxpwsize(void); -/** - * Returns maximum object size supported by Platform KeyStore. - */ u16 plpks_get_maxobjectsize(void); -/** - * Returns maximum object label size supported by Platform KeyStore. - */ u16 plpks_get_maxobjectlabelsize(void); -/** - * Returns total size of the configured Platform KeyStore. - */ u32 plpks_get_totalsize(void); -/** - * Returns used space from the total size of the Platform KeyStore. - */ u32 plpks_get_usedspace(void); -/** - * Returns bitmask of policies supported by the hypervisor. - */ u32 plpks_get_supportedpolicies(void); -/** - * Returns maximum byte size of a single object supported by the hypervisor. - * Only valid for config version >= 3 - */ u32 plpks_get_maxlargeobjectsize(void); -/** - * Returns bitmask of signature algorithms supported for signed updates. - * Only valid for config version >= 3 - */ u64 plpks_get_signedupdatealgorithms(void); -/** - * Returns the length of the PLPKS password in bytes. - */ u16 plpks_get_passwordlen(void); -/** - * Called in early init to retrieve and clear the PLPKS password from the DT. - */ void plpks_early_init_devtree(void); -/** - * Populates the FDT with the PLPKS password to prepare for kexec. - */ int plpks_populate_fdt(void *fdt); #else // CONFIG_PSERIES_PLPKS static inline bool plpks_is_available(void) { return false; } diff --git a/arch/powerpc/platforms/pseries/plpks.c b/arch/powerpc/platforms/pseries/plpks.c index b1667ed05f98..03722fabf9c3 100644 --- a/arch/powerpc/platforms/pseries/plpks.c +++ b/arch/powerpc/platforms/pseries/plpks.c @@ -312,40 +312,107 @@ static int _plpks_get_config(void) return rc; } +/** + * plpks_get_version() - Get the version of the PLPKS config structure. + * + * Successful execution of the H_PKS_GET_CONFIG HCALL during initialization + * reads the PLPKS config structure version and saves it in a file local static + * version variable. + * + * Returns: On success the saved PLPKS config structure version is returned, 0 + * if not. + */ u8 plpks_get_version(void) { return version; } +/** + * plpks_get_objoverhead() - Get the hypervisor storage overhead per object. + * + * Successful execution of the H_PKS_GET_CONFIG HCALL during initialization + * reads the per object hypervisor storage overhead in bytes into the local + * static objoverhead variable, excluding the size of the object or the label. + * This value can be treated as valid only when the PLPKS config structure + * version >= 2. + * + * Returns: If PLPKS config structure version >= 2 then the storage overhead is + * returned, 0 otherwise. + */ u16 plpks_get_objoverhead(void) { return objoverhead; } +/** + * plpks_get_maxpwsize() - Get the maximum password size. + * + * Successful execution of the H_PKS_GET_CONFIG HCALL during initialization + * reads the maximum password size and checks if it is 32 bytes at the least + * before storing it in the local static maxpwsize variable. + * + * Returns: On success the maximum password size is returned, 0 if not. + */ u16 plpks_get_maxpwsize(void) { return maxpwsize; } +/** + * plpks_get_maxobjectsize() - Get the maximum object size supported by the + * PLPKS. + * + * Successful execution of the H_PKS_GET_CONFIG HCALL during initialization + * reads the maximum object size into the file local static maxobjsize variable. + * + * Returns: On success the maximum object size is returned, 0 if not. + */ u16 plpks_get_maxobjectsize(void) { return maxobjsize; } +/** + * plpks_get_maxobjectlabelsize() - Get the maximum object label size supported + * by the PLPKS. + * + * Successful execution of the H_PKS_GET_CONFIG HCALL during initialization + * reads the maximum object label size into the local static maxobjlabelsize + * variable. + * + * Returns: On success the maximum object label size is returned, 0 if not. + */ u16 plpks_get_maxobjectlabelsize(void) { return maxobjlabelsize; } +/** + * plpks_get_totalsize() - Get the total size of the PLPKS that is configured. + * + * Successful execution of the H_PKS_GET_CONFIG HCALL during initialization + * reads the total size of the PLPKS that is configured for the LPAR into the + * file local static totalsize variable. + * + * Returns: On success the total size of the PLPKS configured is returned, 0 if + * not. + */ u32 plpks_get_totalsize(void) { return totalsize; } +/** + * plpks_get_usedspace() - Get the used space from the total size of the PLPKS. + * + * Invoke the H_PKS_GET_CONFIG HCALL to refresh the latest value for the used + * space as this keeps changing with the creation and removal of objects in the + * PLPKS. + * + * Returns: On success the used space is returned, 0 if not. + */ u32 plpks_get_usedspace(void) { - // Unlike other config values, usedspace regularly changes as objects - // are updated, so we need to refresh. int rc = _plpks_get_config(); if (rc) { pr_err("Couldn't get config, rc: %d\n", rc); @@ -354,26 +421,84 @@ u32 plpks_get_usedspace(void) return usedspace; } +/** + * plpks_get_supportedpolicies() - Get a bitmask of the policies supported by + * the hypervisor. + * + * Successful execution of the H_PKS_GET_CONFIG HCALL during initialization + * reads a bitmask of the policies supported by the hypervisor into the file + * local static supportedpolicies variable. + * + * Returns: On success the bitmask of the policies supported by the hypervisor + * are returned, 0 if not. + */ u32 plpks_get_supportedpolicies(void) { return supportedpolicies; } +/** + * plpks_get_maxlargeobjectsize() - Get the maximum object size supported for + * PLPKS config structure version >= 3 + * + * Successful execution of the H_PKS_GET_CONFIG HCALL during initialization + * reads the maximum object size into the local static maxlargeobjectsize + * variable for PLPKS config structure version >= 3. This was introduced + * starting with PLPKS config structure version 3 to allow for objects of + * size >= 64K. + * + * Returns: If PLPKS config structure version >= 3 then the new maximum object + * size is returned, 0 if not. + */ u32 plpks_get_maxlargeobjectsize(void) { return maxlargeobjectsize; } +/** + * plpks_get_signedupdatealgorithms() - Get a bitmask of the signature + * algorithms supported for signed updates. + * + * Successful execution of the H_PKS_GET_CONFIG HCALL during initialization + * reads a bitmask of the signature algorithms supported for signed updates into + * the file local static signedupdatealgorithms variable. This is valid only + * when the PLPKS config structure version >= 3. + * + * Returns: On success the bitmask of the signature algorithms supported for + * signed updates is returned, 0 if not. + */ u64 plpks_get_signedupdatealgorithms(void) { return signedupdatealgorithms; } +/** + * plpks_get_passwordlen() - Get the length of the PLPKS password in bytes. + * + * The H_PKS_GEN_PASSWORD HCALL makes the hypervisor generate a random password + * for the specified consumer, apply that password to the PLPKS and return it to + * the caller. In this process, the password length for the OS consumer is + * stored in the local static ospasswordlength variable. + * + * Returns: On success the password length for the OS consumer in bytes is + * returned, 0 if not. + */ u16 plpks_get_passwordlen(void) { return ospasswordlength; } +/** + * plpks_is_available() - Get the PLPKS availability status for the LPAR. + * + * The availability of PLPKS is inferred based upon the successful execution of + * the H_PKS_GET_CONFIG HCALL provided the firmware supports this feature. The + * H_PKS_GET_CONFIG HCALL reads the configuration and status information related + * to the PLPKS. The configuration structure provides a version number to inform + * the caller of the supported features. + * + * Returns: true is returned if PLPKS is available, false if not. + */ bool plpks_is_available(void) { int rc; @@ -425,6 +550,35 @@ static int plpks_confirm_object_flushed(struct label *label, return pseries_status_to_err(rc); } +/** + * plpks_signed_update_var() - Update the specified authenticated variable. + * @var: authenticated variable to be updated + * @flags: signed update request operation flags + * + * The H_PKS_SIGNED_UPDATE HCALL performs a signed update to an object in the + * PLPKS. The object must have the signed update policy flag set. + * + * Possible reasons for the returned errno values: + * + * -ENXIO if PLPKS is not supported + * -EIO if PLPKS access is blocked due to the LPAR's state + * if PLPKS modification is blocked due to the LPAR's state + * if an error occurred while processing the request + * -EINVAL if invalid authorization parameter + * if invalid object label parameter + * if invalid object label len parameter + * if invalid or unsupported policy declaration + * if invalid signed update flags + * if invalid input data parameter + * if invalid input data len parameter + * if invalid continue token parameter + * -EPERM if access is denied + * -ENOMEM if there is inadequate memory to perform the operation + * -EBUSY if unable to handle the request or long running operation + * initiated, retry later + * + * Returns: On success 0 is returned, a negative errno if not. + */ int plpks_signed_update_var(struct plpks_var *var, u64 flags) { unsigned long retbuf[PLPAR_HCALL9_BUFSIZE] = {0}; @@ -481,6 +635,33 @@ int plpks_signed_update_var(struct plpks_var *var, u64 flags) return rc; } +/** + * plpks_write_var() - Write the specified variable and its data to PLPKS. + * @var: variable to be written into the PLPKS + * + * The H_PKS_WRITE_OBJECT HCALL writes an object into the PLPKS. The caller must + * provide a valid component type for the variable, and the signed update policy + * flag must not be set. + * + * Possible reasons for the returned errno values: + * + * -ENXIO if PLPKS is not supported + * -EIO if PLPKS access is blocked due to the LPAR's state + * if PLPKS modification is blocked due to the LPAR's state + * if an error occurred while processing the request + * -EINVAL if invalid authorization parameter + * if invalid object label parameter + * if invalid object label len parameter + * if invalid or unsupported policy declaration + * if invalid input data parameter + * if invalid input data len parameter + * -EPERM if access is denied + * -ENOMEM if unable to store the requested object in the space available + * -EBUSY if unable to handle the request + * -EEXIST if the object label already exists + * + * Returns: On success 0 is returned, a negative errno if not. + */ int plpks_write_var(struct plpks_var var) { unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 }; @@ -520,6 +701,30 @@ int plpks_write_var(struct plpks_var var) return rc; } +/** + * plpks_remove_var() - Remove the specified variable and its data from PLPKS. + * @component: metadata prefix in the object label metadata structure + * @varos: metadata OS flags in the object label metadata structure + * @vname: object label for the object that needs to be removed + * + * The H_PKS_REMOVE_OBJECT HCALL removes an object from the PLPKS. The removal + * is independent of the policy bits that are set. + * + * Possible reasons for the returned errno values: + * + * -ENXIO if PLPKS is not supported + * -EIO if PLPKS access is blocked due to the LPAR's state + * if PLPKS modification is blocked due to the LPAR's state + * if an error occurred while processing the request + * -EINVAL if invalid authorization parameter + * if invalid object label parameter + * if invalid object label len parameter + * -EPERM if access is denied + * -ENOENT if the requested object was not found + * -EBUSY if unable to handle the request + * + * Returns: On success 0 is returned, a negative errno if not. + */ int plpks_remove_var(char *component, u8 varos, struct plpks_var_name vname) { unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 }; @@ -619,21 +824,119 @@ static int plpks_read_var(u8 consumer, struct plpks_var *var) return rc; } +/** + * plpks_read_os_var() - Fetch the data for the specified variable that is + * owned by the OS consumer. + * @var: variable to be read from the PLPKS + * + * The consumer or the owner of the object is the os kernel. The + * H_PKS_READ_OBJECT HCALL reads an object from the PLPKS. The caller must + * allocate the buffer var->data and specify the length for this buffer in + * var->datalen. If no buffer is provided, var->datalen will be populated with + * the requested object's size. + * + * Possible reasons for the returned errno values: + * + * -ENXIO if PLPKS is not supported + * -EIO if PLPKS access is blocked due to the LPAR's state + * if an error occurred while processing the request + * -EINVAL if invalid authorization parameter + * if invalid object label parameter + * if invalid object label len parameter + * if invalid output data parameter + * if invalid output data len parameter + * -EPERM if access is denied + * -ENOENT if the requested object was not found + * -EFBIG if the requested object couldn't be + * stored in the buffer provided + * -EBUSY if unable to handle the request + * + * Returns: On success 0 is returned, a negative errno if not. + */ int plpks_read_os_var(struct plpks_var *var) { return plpks_read_var(PLPKS_OS_OWNER, var); } +/** + * plpks_read_fw_var() - Fetch the data for the specified variable that is + * owned by the firmware consumer. + * @var: variable to be read from the PLPKS + * + * The consumer or the owner of the object is the firmware. The + * H_PKS_READ_OBJECT HCALL reads an object from the PLPKS. The caller must + * allocate the buffer var->data and specify the length for this buffer in + * var->datalen. If no buffer is provided, var->datalen will be populated with + * the requested object's size. + * + * Possible reasons for the returned errno values: + * + * -ENXIO if PLPKS is not supported + * -EIO if PLPKS access is blocked due to the LPAR's state + * if an error occurred while processing the request + * -EINVAL if invalid authorization parameter + * if invalid object label parameter + * if invalid object label len parameter + * if invalid output data parameter + * if invalid output data len parameter + * -EPERM if access is denied + * -ENOENT if the requested object was not found + * -EFBIG if the requested object couldn't be + * stored in the buffer provided + * -EBUSY if unable to handle the request + * + * Returns: On success 0 is returned, a negative errno if not. + */ int plpks_read_fw_var(struct plpks_var *var) { return plpks_read_var(PLPKS_FW_OWNER, var); } +/** + * plpks_read_bootloader_var() - Fetch the data for the specified variable + * owned by the bootloader consumer. + * @var: variable to be read from the PLPKS + * + * The consumer or the owner of the object is the bootloader. The + * H_PKS_READ_OBJECT HCALL reads an object from the PLPKS. The caller must + * allocate the buffer var->data and specify the length for this buffer in + * var->datalen. If no buffer is provided, var->datalen will be populated with + * the requested object's size. + * + * Possible reasons for the returned errno values: + * + * -ENXIO if PLPKS is not supported + * -EIO if PLPKS access is blocked due to the LPAR's state + * if an error occurred while processing the request + * -EINVAL if invalid authorization parameter + * if invalid object label parameter + * if invalid object label len parameter + * if invalid output data parameter + * if invalid output data len parameter + * -EPERM if access is denied + * -ENOENT if the requested object was not found + * -EFBIG if the requested object couldn't be + * stored in the buffer provided + * -EBUSY if unable to handle the request + * + * Returns: On success 0 is returned, a negative errno if not. + */ int plpks_read_bootloader_var(struct plpks_var *var) { return plpks_read_var(PLPKS_BOOTLOADER_OWNER, var); } +/** + * plpks_populate_fdt(): Populates the FDT with the PLPKS password to prepare + * for kexec. + * @fdt: pointer to the device tree blob + * + * Upon confirming the existence of the chosen node, invoke fdt_setprop to + * populate the device tree with the PLPKS password in order to prepare for + * kexec. + * + * Returns: On success 0 is returned, a negative value if not. + */ int plpks_populate_fdt(void *fdt) { int chosen_offset = fdt_path_offset(fdt, "/chosen"); @@ -647,14 +950,19 @@ int plpks_populate_fdt(void *fdt) return fdt_setprop(fdt, chosen_offset, "ibm,plpks-pw", ospassword, ospasswordlength); } -// Once a password is registered with the hypervisor it cannot be cleared without -// rebooting the LPAR, so to keep using the PLPKS across kexec boots we need to -// recover the previous password from the FDT. -// -// There are a few challenges here. We don't want the password to be visible to -// users, so we need to clear it from the FDT. This has to be done in early boot. -// Clearing it from the FDT would make the FDT's checksum invalid, so we have to -// manually cause the checksum to be recalculated. +/** + * plpks_early_init_devtree() - Retrieves and clears the PLPKS password from the + * DT in early init. + * + * Once a password is registered with the hypervisor it cannot be cleared + * without rebooting the LPAR, so to keep using the PLPKS across kexec boots we + * need to recover the previous password from the FDT. + * + * There are a few challenges here. We don't want the password to be visible to + * users, so we need to clear it from the FDT. This has to be done in early + * boot. Clearing it from the FDT would make the FDT's checksum invalid, so we + * have to manually cause the checksum to be recalculated. + */ void __init plpks_early_init_devtree(void) { void *fdt = initial_boot_params; -- 2.47.3
