diff options
Diffstat (limited to 'arch/powerpc/platforms/pseries/plpks.c')
-rw-r--r-- | arch/powerpc/platforms/pseries/plpks.c | 385 |
1 files changed, 319 insertions, 66 deletions
diff --git a/arch/powerpc/platforms/pseries/plpks.c b/arch/powerpc/platforms/pseries/plpks.c index 4edd1585e245..6f7bf3fc3aea 100644 --- a/arch/powerpc/platforms/pseries/plpks.c +++ b/arch/powerpc/platforms/pseries/plpks.c @@ -16,30 +16,28 @@ #include <linux/slab.h> #include <linux/string.h> #include <linux/types.h> +#include <linux/of_fdt.h> +#include <linux/libfdt.h> +#include <linux/memblock.h> #include <asm/hvcall.h> #include <asm/machdep.h> - -#include "plpks.h" - -#define PKS_FW_OWNER 0x1 -#define PKS_BOOTLOADER_OWNER 0x2 -#define PKS_OS_OWNER 0x3 - -#define LABEL_VERSION 0 -#define MAX_LABEL_ATTR_SIZE 16 -#define MAX_NAME_SIZE 239 -#define MAX_DATA_SIZE 4000 - -#define PKS_FLUSH_MAX_TIMEOUT 5000 //msec -#define PKS_FLUSH_SLEEP 10 //msec -#define PKS_FLUSH_SLEEP_RANGE 400 +#include <asm/plpks.h> +#include <asm/firmware.h> static u8 *ospassword; static u16 ospasswordlength; // Retrieved with H_PKS_GET_CONFIG +static u8 version; +static u16 objoverhead; static u16 maxpwsize; static u16 maxobjsize; +static s16 maxobjlabelsize; +static u32 totalsize; +static u32 usedspace; +static u32 supportedpolicies; +static u32 maxlargeobjectsize; +static u64 signedupdatealgorithms; struct plpks_auth { u8 version; @@ -60,7 +58,7 @@ struct label_attr { struct label { struct label_attr attr; - u8 name[MAX_NAME_SIZE]; + u8 name[PLPKS_MAX_NAME_SIZE]; size_t size; }; @@ -87,6 +85,12 @@ static int pseries_status_to_err(int rc) err = -ENOENT; break; case H_BUSY: + case H_LONG_BUSY_ORDER_1_MSEC: + case H_LONG_BUSY_ORDER_10_MSEC: + case H_LONG_BUSY_ORDER_100_MSEC: + case H_LONG_BUSY_ORDER_1_SEC: + case H_LONG_BUSY_ORDER_10_SEC: + case H_LONG_BUSY_ORDER_100_SEC: err = -EBUSY; break; case H_AUTHORITY: @@ -117,16 +121,25 @@ static int pseries_status_to_err(int rc) err = -EINVAL; } + pr_debug("Converted hypervisor code %d to Linux %d\n", rc, err); + return err; } static int plpks_gen_password(void) { unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 }; - u8 *password, consumer = PKS_OS_OWNER; + u8 *password, consumer = PLPKS_OS_OWNER; int rc; - password = kzalloc(maxpwsize, GFP_KERNEL); + // If we booted from kexec, we could be reusing an existing password already + if (ospassword) { + pr_debug("Password of length %u already in use\n", ospasswordlength); + return 0; + } + + // The password must not cross a page boundary, so we align to the next power of 2 + password = kzalloc(roundup_pow_of_two(maxpwsize), GFP_KERNEL); if (!password) return -ENOMEM; @@ -143,7 +156,7 @@ static int plpks_gen_password(void) memcpy(ospassword, password, ospasswordlength); } else { if (rc == H_IN_USE) { - pr_warn("Password is already set for POWER LPAR Platform KeyStore\n"); + pr_warn("Password already set - authenticated operations will fail\n"); rc = 0; } else { goto out; @@ -159,17 +172,19 @@ static struct plpks_auth *construct_auth(u8 consumer) { struct plpks_auth *auth; - if (consumer > PKS_OS_OWNER) + if (consumer > PLPKS_OS_OWNER) return ERR_PTR(-EINVAL); - auth = kzalloc(struct_size(auth, password, maxpwsize), GFP_KERNEL); + // The auth structure must not cross a page boundary and must be + // 16 byte aligned. We align to the next largest power of 2 + auth = kzalloc(roundup_pow_of_two(struct_size(auth, password, maxpwsize)), GFP_KERNEL); if (!auth) return ERR_PTR(-ENOMEM); auth->version = 1; auth->consumer = consumer; - if (consumer == PKS_FW_OWNER || consumer == PKS_BOOTLOADER_OWNER) + if (consumer == PLPKS_FW_OWNER || consumer == PLPKS_BOOTLOADER_OWNER) return auth; memcpy(auth->password, ospassword, ospasswordlength); @@ -187,25 +202,29 @@ static struct label *construct_label(char *component, u8 varos, u8 *name, u16 namelen) { struct label *label; - size_t slen; + size_t slen = 0; - if (!name || namelen > MAX_NAME_SIZE) + if (!name || namelen > PLPKS_MAX_NAME_SIZE) return ERR_PTR(-EINVAL); - slen = strlen(component); - if (component && slen > sizeof(label->attr.prefix)) - return ERR_PTR(-EINVAL); + // Support NULL component for signed updates + if (component) { + slen = strlen(component); + if (slen > sizeof(label->attr.prefix)) + return ERR_PTR(-EINVAL); + } - label = kzalloc(sizeof(*label), GFP_KERNEL); + // The label structure must not cross a page boundary, so we align to the next power of 2 + label = kzalloc(roundup_pow_of_two(sizeof(*label)), GFP_KERNEL); if (!label) return ERR_PTR(-ENOMEM); if (component) memcpy(&label->attr.prefix, component, slen); - label->attr.version = LABEL_VERSION; + label->attr.version = PLPKS_LABEL_VERSION; label->attr.os = varos; - label->attr.length = MAX_LABEL_ATTR_SIZE; + label->attr.length = PLPKS_MAX_LABEL_ATTR_SIZE; memcpy(&label->name, name, namelen); label->size = sizeof(struct label_attr) + namelen; @@ -216,38 +235,164 @@ static struct label *construct_label(char *component, u8 varos, u8 *name, static int _plpks_get_config(void) { unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 }; - struct { + struct config { u8 version; u8 flags; - __be32 rsvd0; + __be16 rsvd0; + __be16 objoverhead; __be16 maxpwsize; __be16 maxobjlabelsize; __be16 maxobjsize; __be32 totalsize; __be32 usedspace; __be32 supportedpolicies; - __be64 rsvd1; - } __packed config; + __be32 maxlargeobjectsize; + __be64 signedupdatealgorithms; + u8 rsvd1[476]; + } __packed * config; size_t size; - int rc; + int rc = 0; + + size = sizeof(*config); + + // Config struct must not cross a page boundary. So long as the struct + // size is a power of 2, this should be fine as alignment is guaranteed + config = kzalloc(size, GFP_KERNEL); + if (!config) { + rc = -ENOMEM; + goto err; + } + + rc = plpar_hcall(H_PKS_GET_CONFIG, retbuf, virt_to_phys(config), size); + + if (rc != H_SUCCESS) { + rc = pseries_status_to_err(rc); + goto err; + } + + version = config->version; + objoverhead = be16_to_cpu(config->objoverhead); + maxpwsize = be16_to_cpu(config->maxpwsize); + maxobjsize = be16_to_cpu(config->maxobjsize); + maxobjlabelsize = be16_to_cpu(config->maxobjlabelsize); + totalsize = be32_to_cpu(config->totalsize); + usedspace = be32_to_cpu(config->usedspace); + supportedpolicies = be32_to_cpu(config->supportedpolicies); + maxlargeobjectsize = be32_to_cpu(config->maxlargeobjectsize); + signedupdatealgorithms = be64_to_cpu(config->signedupdatealgorithms); + + // Validate that the numbers we get back match the requirements of the spec + if (maxpwsize < 32) { + pr_err("Invalid Max Password Size received from hypervisor (%d < 32)\n", maxpwsize); + rc = -EIO; + goto err; + } + + if (maxobjlabelsize < 255) { + pr_err("Invalid Max Object Label Size received from hypervisor (%d < 255)\n", + maxobjlabelsize); + rc = -EIO; + goto err; + } + + if (totalsize < 4096) { + pr_err("Invalid Total Size received from hypervisor (%d < 4096)\n", totalsize); + rc = -EIO; + goto err; + } + + if (version >= 3 && maxlargeobjectsize >= 65536 && maxobjsize != 0xFFFF) { + pr_err("Invalid Max Object Size (0x%x != 0xFFFF)\n", maxobjsize); + rc = -EIO; + goto err; + } + +err: + kfree(config); + return rc; +} + +u8 plpks_get_version(void) +{ + return version; +} + +u16 plpks_get_objoverhead(void) +{ + return objoverhead; +} + +u16 plpks_get_maxpwsize(void) +{ + return maxpwsize; +} + +u16 plpks_get_maxobjectsize(void) +{ + return maxobjsize; +} + +u16 plpks_get_maxobjectlabelsize(void) +{ + return maxobjlabelsize; +} + +u32 plpks_get_totalsize(void) +{ + return totalsize; +} + +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); + return 0; + } + return usedspace; +} + +u32 plpks_get_supportedpolicies(void) +{ + return supportedpolicies; +} + +u32 plpks_get_maxlargeobjectsize(void) +{ + return maxlargeobjectsize; +} + +u64 plpks_get_signedupdatealgorithms(void) +{ + return signedupdatealgorithms; +} - size = sizeof(config); +u16 plpks_get_passwordlen(void) +{ + return ospasswordlength; +} - rc = plpar_hcall(H_PKS_GET_CONFIG, retbuf, virt_to_phys(&config), size); +bool plpks_is_available(void) +{ + int rc; - if (rc != H_SUCCESS) - return pseries_status_to_err(rc); + if (!firmware_has_feature(FW_FEATURE_LPAR)) + return false; - maxpwsize = be16_to_cpu(config.maxpwsize); - maxobjsize = be16_to_cpu(config.maxobjsize); + rc = _plpks_get_config(); + if (rc) + return false; - return 0; + return true; } static int plpks_confirm_object_flushed(struct label *label, struct plpks_auth *auth) { unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 }; + bool timed_out = true; u64 timeout = 0; u8 status; int rc; @@ -259,20 +404,79 @@ static int plpks_confirm_object_flushed(struct label *label, status = retbuf[0]; if (rc) { + timed_out = false; if (rc == H_NOT_FOUND && status == 1) rc = 0; break; } - if (!rc && status == 1) + if (!rc && status == 1) { + timed_out = false; break; + } - usleep_range(PKS_FLUSH_SLEEP, - PKS_FLUSH_SLEEP + PKS_FLUSH_SLEEP_RANGE); - timeout = timeout + PKS_FLUSH_SLEEP; - } while (timeout < PKS_FLUSH_MAX_TIMEOUT); + usleep_range(PLPKS_FLUSH_SLEEP, + PLPKS_FLUSH_SLEEP + PLPKS_FLUSH_SLEEP_RANGE); + timeout = timeout + PLPKS_FLUSH_SLEEP; + } while (timeout < PLPKS_MAX_TIMEOUT); - rc = pseries_status_to_err(rc); + if (timed_out) + return -ETIMEDOUT; + + return pseries_status_to_err(rc); +} + +int plpks_signed_update_var(struct plpks_var *var, u64 flags) +{ + unsigned long retbuf[PLPAR_HCALL9_BUFSIZE] = {0}; + int rc; + struct label *label; + struct plpks_auth *auth; + u64 continuetoken = 0; + u64 timeout = 0; + + if (!var->data || var->datalen <= 0 || var->namelen > PLPKS_MAX_NAME_SIZE) + return -EINVAL; + + if (!(var->policy & PLPKS_SIGNEDUPDATE)) + return -EINVAL; + + // Signed updates need the component to be NULL. + if (var->component) + return -EINVAL; + + auth = construct_auth(PLPKS_OS_OWNER); + if (IS_ERR(auth)) + return PTR_ERR(auth); + + label = construct_label(var->component, var->os, var->name, var->namelen); + if (IS_ERR(label)) { + rc = PTR_ERR(label); + goto out; + } + + do { + rc = plpar_hcall9(H_PKS_SIGNED_UPDATE, retbuf, + virt_to_phys(auth), virt_to_phys(label), + label->size, var->policy, flags, + virt_to_phys(var->data), var->datalen, + continuetoken); + + continuetoken = retbuf[0]; + if (pseries_status_to_err(rc) == -EBUSY) { + int delay_ms = get_longbusy_msecs(rc); + mdelay(delay_ms); + timeout += delay_ms; + } + rc = pseries_status_to_err(rc); + } while (rc == -EBUSY && timeout < PLPKS_MAX_TIMEOUT); + + if (!rc) + rc = plpks_confirm_object_flushed(label, auth); + + kfree(label); +out: + kfree(auth); return rc; } @@ -285,13 +489,13 @@ int plpks_write_var(struct plpks_var var) int rc; if (!var.component || !var.data || var.datalen <= 0 || - var.namelen > MAX_NAME_SIZE || var.datalen > MAX_DATA_SIZE) + var.namelen > PLPKS_MAX_NAME_SIZE || var.datalen > PLPKS_MAX_DATA_SIZE) return -EINVAL; - if (var.policy & SIGNEDUPDATE) + if (var.policy & PLPKS_SIGNEDUPDATE) return -EINVAL; - auth = construct_auth(PKS_OS_OWNER); + auth = construct_auth(PLPKS_OS_OWNER); if (IS_ERR(auth)) return PTR_ERR(auth); @@ -323,10 +527,10 @@ int plpks_remove_var(char *component, u8 varos, struct plpks_var_name vname) struct label *label; int rc; - if (!component || vname.namelen > MAX_NAME_SIZE) + if (vname.namelen > PLPKS_MAX_NAME_SIZE) return -EINVAL; - auth = construct_auth(PKS_OS_OWNER); + auth = construct_auth(PLPKS_OS_OWNER); if (IS_ERR(auth)) return PTR_ERR(auth); @@ -358,14 +562,14 @@ static int plpks_read_var(u8 consumer, struct plpks_var *var) u8 *output; int rc; - if (var->namelen > MAX_NAME_SIZE) + if (var->namelen > PLPKS_MAX_NAME_SIZE) return -EINVAL; auth = construct_auth(consumer); if (IS_ERR(auth)) return PTR_ERR(auth); - if (consumer == PKS_OS_OWNER) { + if (consumer == PLPKS_OS_OWNER) { label = construct_label(var->component, var->os, var->name, var->namelen); if (IS_ERR(label)) { @@ -380,7 +584,7 @@ static int plpks_read_var(u8 consumer, struct plpks_var *var) goto out_free_label; } - if (consumer == PKS_OS_OWNER) + if (consumer == PLPKS_OS_OWNER) rc = plpar_hcall(H_PKS_READ_OBJECT, retbuf, virt_to_phys(auth), virt_to_phys(label), label->size, virt_to_phys(output), maxobjsize); @@ -395,17 +599,14 @@ static int plpks_read_var(u8 consumer, struct plpks_var *var) goto out_free_output; } - if (var->datalen == 0 || var->datalen > retbuf[0]) + if (!var->data || var->datalen > retbuf[0]) var->datalen = retbuf[0]; - var->data = kzalloc(var->datalen, GFP_KERNEL); - if (!var->data) { - rc = -ENOMEM; - goto out_free_output; - } var->policy = retbuf[1]; - memcpy(var->data, output, var->datalen); + if (var->data) + memcpy(var->data, output, var->datalen); + rc = 0; out_free_output: @@ -420,17 +621,69 @@ out_free_auth: int plpks_read_os_var(struct plpks_var *var) { - return plpks_read_var(PKS_OS_OWNER, var); + return plpks_read_var(PLPKS_OS_OWNER, var); } int plpks_read_fw_var(struct plpks_var *var) { - return plpks_read_var(PKS_FW_OWNER, var); + return plpks_read_var(PLPKS_FW_OWNER, var); } int plpks_read_bootloader_var(struct plpks_var *var) { - return plpks_read_var(PKS_BOOTLOADER_OWNER, var); + return plpks_read_var(PLPKS_BOOTLOADER_OWNER, var); +} + +int plpks_populate_fdt(void *fdt) +{ + int chosen_offset = fdt_path_offset(fdt, "/chosen"); + + if (chosen_offset < 0) { + pr_err("Can't find chosen node: %s\n", + fdt_strerror(chosen_offset)); + return chosen_offset; + } + + 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. +void __init plpks_early_init_devtree(void) +{ + void *fdt = initial_boot_params; + int chosen_node = fdt_path_offset(fdt, "/chosen"); + const u8 *password; + int len; + + if (chosen_node < 0) + return; + + password = fdt_getprop(fdt, chosen_node, "ibm,plpks-pw", &len); + if (len <= 0) { + pr_debug("Couldn't find ibm,plpks-pw node.\n"); + return; + } + + ospassword = memblock_alloc_raw(len, SMP_CACHE_BYTES); + if (!ospassword) { + pr_err("Error allocating memory for password.\n"); + goto out; + } + + memcpy(ospassword, password, len); + ospasswordlength = (u16)len; + +out: + fdt_nop_property(fdt, chosen_node, "ibm,plpks-pw"); + // Since we've cleared the password, we must update the FDT checksum + early_init_dt_verify(fdt); } static __init int pseries_plpks_init(void) |