From 636259880a7e7d3446a707dddebc799da94bdd0b Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Sat, 12 Nov 2016 21:32:31 +0000 Subject: efi: Add support for seeding the RNG from a UEFI config table Specify a Linux specific UEFI configuration table that carries some random bits, and use the contents during early boot to seed the kernel's random number generator. This allows much strong random numbers to be generated early on. The entropy is fed to the kernel using add_device_randomness(), which is documented as being appropriate for being called very early. Since UEFI configuration tables may also be consumed by kexec'd kernels, register a reboot notifier that updates the seed in the table. Note that the config table could be generated by the EFI stub or by any other UEFI driver or application (e.g., GRUB), but the random seed table GUID and the associated functionality should be considered an internal kernel interface (unless it is promoted to ABI later on) Signed-off-by: Ard Biesheuvel Signed-off-by: Matt Fleming Reviewed-by: Kees Cook Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20161112213237.8804-4-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar --- include/linux/efi.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/linux') diff --git a/include/linux/efi.h b/include/linux/efi.h index 2d089487d2da..85e28b138cdd 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -599,6 +599,7 @@ void efi_native_runtime_setup(void); */ #define LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID EFI_GUID(0xe03fc20a, 0x85dc, 0x406e, 0xb9, 0x0e, 0x4a, 0xb5, 0x02, 0x37, 0x1d, 0x95) #define LINUX_EFI_LOADER_ENTRY_GUID EFI_GUID(0x4a67b082, 0x0a4c, 0x41cf, 0xb6, 0xc7, 0x44, 0x0b, 0x29, 0xbb, 0x8c, 0x4f) +#define LINUX_EFI_RANDOM_SEED_TABLE_GUID EFI_GUID(0x1ce1e5bc, 0x7ceb, 0x42f2, 0x81, 0xe5, 0x8a, 0xad, 0xf1, 0x80, 0xf5, 0x7b) typedef struct { efi_guid_t guid; @@ -872,6 +873,7 @@ extern struct efi { unsigned long esrt; /* ESRT table */ unsigned long properties_table; /* properties table */ unsigned long mem_attr_table; /* memory attributes table */ + unsigned long rng_seed; /* UEFI firmware random seed */ efi_get_time_t *get_time; efi_set_time_t *set_time; efi_get_wakeup_time_t *get_wakeup_time; @@ -1493,4 +1495,10 @@ efi_status_t efi_exit_boot_services(efi_system_table_t *sys_table, struct efi_boot_memmap *map, void *priv, efi_exit_boot_map_processing priv_func); + +struct linux_efi_random_seed { + u32 size; + u8 bits[]; +}; + #endif /* _LINUX_EFI_H */ -- cgit v1.2.3 From 568bc4e87033d232c5fd00d5b0cd22a2ccc04944 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Sat, 12 Nov 2016 21:32:33 +0000 Subject: efi/arm*/libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table Invoke the EFI_RNG_PROTOCOL protocol in the context of the stub and install the Linux-specific RNG seed UEFI config table. This will be picked up by the EFI routines in the core kernel to seed the kernel entropy pool. Signed-off-by: Ard Biesheuvel Signed-off-by: Matt Fleming Reviewed-by: Kees Cook Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20161112213237.8804-6-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar --- drivers/firmware/efi/libstub/arm-stub.c | 2 ++ drivers/firmware/efi/libstub/efistub.h | 2 ++ drivers/firmware/efi/libstub/random.c | 48 +++++++++++++++++++++++++++++++++ include/linux/efi.h | 1 + 4 files changed, 53 insertions(+) (limited to 'include/linux') diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c index 993aa56755f6..b4f7d78f9e8b 100644 --- a/drivers/firmware/efi/libstub/arm-stub.c +++ b/drivers/firmware/efi/libstub/arm-stub.c @@ -340,6 +340,8 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table, if (status != EFI_SUCCESS) pr_efi_err(sys_table, "Failed initrd from command line!\n"); + efi_random_get_seed(sys_table); + new_fdt_addr = fdt_addr; status = allocate_new_fdt_and_exit_boot(sys_table, handle, &new_fdt_addr, dram_base + MAX_FDT_OFFSET, diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index fe1f22584c69..b98824e3800a 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -71,4 +71,6 @@ efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg, efi_status_t check_platform_features(efi_system_table_t *sys_table_arg); +efi_status_t efi_random_get_seed(efi_system_table_t *sys_table_arg); + #endif diff --git a/drivers/firmware/efi/libstub/random.c b/drivers/firmware/efi/libstub/random.c index f8e2e5ae6872..3a3feacc329f 100644 --- a/drivers/firmware/efi/libstub/random.c +++ b/drivers/firmware/efi/libstub/random.c @@ -143,3 +143,51 @@ efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg, return status; } + +#define RANDOM_SEED_SIZE 32 + +efi_status_t efi_random_get_seed(efi_system_table_t *sys_table_arg) +{ + efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID; + efi_guid_t rng_algo_raw = EFI_RNG_ALGORITHM_RAW; + efi_guid_t rng_table_guid = LINUX_EFI_RANDOM_SEED_TABLE_GUID; + struct efi_rng_protocol *rng; + struct linux_efi_random_seed *seed; + efi_status_t status; + + status = efi_call_early(locate_protocol, &rng_proto, NULL, + (void **)&rng); + if (status != EFI_SUCCESS) + return status; + + status = efi_call_early(allocate_pool, EFI_RUNTIME_SERVICES_DATA, + sizeof(*seed) + RANDOM_SEED_SIZE, + (void **)&seed); + if (status != EFI_SUCCESS) + return status; + + status = rng->get_rng(rng, &rng_algo_raw, RANDOM_SEED_SIZE, + seed->bits); + if (status == EFI_UNSUPPORTED) + /* + * Use whatever algorithm we have available if the raw algorithm + * is not implemented. + */ + status = rng->get_rng(rng, NULL, RANDOM_SEED_SIZE, + seed->bits); + + if (status != EFI_SUCCESS) + goto err_freepool; + + seed->size = RANDOM_SEED_SIZE; + status = efi_call_early(install_configuration_table, &rng_table_guid, + seed); + if (status != EFI_SUCCESS) + goto err_freepool; + + return EFI_SUCCESS; + +err_freepool: + efi_call_early(free_pool, seed); + return status; +} diff --git a/include/linux/efi.h b/include/linux/efi.h index 85e28b138cdd..f5a821d9b90c 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -589,6 +589,7 @@ void efi_native_runtime_setup(void); #define DEVICE_TREE_GUID EFI_GUID(0xb1b621d5, 0xf19c, 0x41a5, 0x83, 0x0b, 0xd9, 0x15, 0x2c, 0x69, 0xaa, 0xe0) #define EFI_PROPERTIES_TABLE_GUID EFI_GUID(0x880aaca3, 0x4adc, 0x4a04, 0x90, 0x79, 0xb7, 0x47, 0x34, 0x08, 0x25, 0xe5) #define EFI_RNG_PROTOCOL_GUID EFI_GUID(0x3152bca5, 0xeade, 0x433d, 0x86, 0x2e, 0xc0, 0x1c, 0xdc, 0x29, 0x1f, 0x44) +#define EFI_RNG_ALGORITHM_RAW EFI_GUID(0xe43176d7, 0xb6e8, 0x4827, 0xb7, 0x84, 0x7f, 0xfd, 0xc4, 0xb6, 0x85, 0x61) #define EFI_MEMORY_ATTRIBUTES_TABLE_GUID EFI_GUID(0xdcfa911d, 0x26eb, 0x469f, 0xa2, 0x20, 0x38, 0xb7, 0xdc, 0x46, 0x12, 0x20) #define EFI_CONSOLE_OUT_DEVICE_GUID EFI_GUID(0xd3b36f2c, 0xd551, 0x11d4, 0x9a, 0x46, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d) -- cgit v1.2.3 From 46cd4b75cd0edee76e0096225c2d31f8d90e92a2 Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Sat, 12 Nov 2016 21:32:34 +0000 Subject: efi: Add device path parser We're about to extended the efistub to retrieve device properties from EFI on Apple Macs. The properties use EFI Device Paths to indicate the device they belong to. This commit adds a parser which, given an EFI Device Path, locates the corresponding struct device and returns a reference to it. Initially only ACPI and PCI Device Path nodes are supported, these are the only types needed for Apple device properties (the corresponding macOS function AppleACPIPlatformExpert::matchEFIDevicePath() does not support any others). Further node types can be added with little to moderate effort. Apple device properties is currently the only use case of this parser, but Peter Jones intends to use it to match up devices with the ConInDev/ConOutDev/ErrOutDev variables and add sysfs attributes to these devices to say the hardware supports using them as console. Thus, make this parser a separate component which can be selected with config option EFI_DEV_PATH_PARSER. It can in principle be compiled as a module if acpi_get_first_physical_node() and acpi_bus_type are exported (and efi_get_device_by_path() itself is exported). The dependency on CONFIG_ACPI is needed for acpi_match_device_ids(). It can be removed if an empty inline stub is added for that function. Signed-off-by: Lukas Wunner Signed-off-by: Matt Fleming Cc: Andreas Noever Cc: Ard Biesheuvel Cc: Linus Torvalds Cc: Peter Jones Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20161112213237.8804-7-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar --- drivers/firmware/efi/Kconfig | 5 + drivers/firmware/efi/Makefile | 1 + drivers/firmware/efi/dev-path-parser.c | 203 +++++++++++++++++++++++++++++++++ include/linux/efi.h | 20 ++++ 4 files changed, 229 insertions(+) create mode 100644 drivers/firmware/efi/dev-path-parser.c (limited to 'include/linux') diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index c981be17d3c0..893fda48fcdd 100644 --- a/drivers/firmware/efi/Kconfig +++ b/drivers/firmware/efi/Kconfig @@ -133,3 +133,8 @@ endmenu config UEFI_CPER bool + +config EFI_DEV_PATH_PARSER + bool + depends on ACPI + default n diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index c8a439f6d715..3e91ae31f9d1 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -21,6 +21,7 @@ obj-$(CONFIG_EFI_STUB) += libstub/ obj-$(CONFIG_EFI_FAKE_MEMMAP) += fake_mem.o obj-$(CONFIG_EFI_BOOTLOADER_CONTROL) += efibc.o obj-$(CONFIG_EFI_TEST) += test/ +obj-$(CONFIG_EFI_DEV_PATH_PARSER) += dev-path-parser.o arm-obj-$(CONFIG_EFI) := arm-init.o arm-runtime.o obj-$(CONFIG_ARM) += $(arm-obj-y) diff --git a/drivers/firmware/efi/dev-path-parser.c b/drivers/firmware/efi/dev-path-parser.c new file mode 100644 index 000000000000..85d1834ee9b7 --- /dev/null +++ b/drivers/firmware/efi/dev-path-parser.c @@ -0,0 +1,203 @@ +/* + * dev-path-parser.c - EFI Device Path parser + * Copyright (C) 2016 Lukas Wunner + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License (version 2) as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +#include +#include +#include + +struct acpi_hid_uid { + struct acpi_device_id hid[2]; + char uid[11]; /* UINT_MAX + null byte */ +}; + +static int __init match_acpi_dev(struct device *dev, void *data) +{ + struct acpi_hid_uid hid_uid = *(struct acpi_hid_uid *)data; + struct acpi_device *adev = to_acpi_device(dev); + + if (acpi_match_device_ids(adev, hid_uid.hid)) + return 0; + + if (adev->pnp.unique_id) + return !strcmp(adev->pnp.unique_id, hid_uid.uid); + else + return !strcmp("0", hid_uid.uid); +} + +static long __init parse_acpi_path(struct efi_dev_path *node, + struct device *parent, struct device **child) +{ + struct acpi_hid_uid hid_uid = {}; + struct device *phys_dev; + + if (node->length != 12) + return -EINVAL; + + sprintf(hid_uid.hid[0].id, "%c%c%c%04X", + 'A' + ((node->acpi.hid >> 10) & 0x1f) - 1, + 'A' + ((node->acpi.hid >> 5) & 0x1f) - 1, + 'A' + ((node->acpi.hid >> 0) & 0x1f) - 1, + node->acpi.hid >> 16); + sprintf(hid_uid.uid, "%u", node->acpi.uid); + + *child = bus_find_device(&acpi_bus_type, NULL, &hid_uid, + match_acpi_dev); + if (!*child) + return -ENODEV; + + phys_dev = acpi_get_first_physical_node(to_acpi_device(*child)); + if (phys_dev) { + get_device(phys_dev); + put_device(*child); + *child = phys_dev; + } + + return 0; +} + +static int __init match_pci_dev(struct device *dev, void *data) +{ + unsigned int devfn = *(unsigned int *)data; + + return dev_is_pci(dev) && to_pci_dev(dev)->devfn == devfn; +} + +static long __init parse_pci_path(struct efi_dev_path *node, + struct device *parent, struct device **child) +{ + unsigned int devfn; + + if (node->length != 6) + return -EINVAL; + if (!parent) + return -EINVAL; + + devfn = PCI_DEVFN(node->pci.dev, node->pci.fn); + + *child = device_find_child(parent, &devfn, match_pci_dev); + if (!*child) + return -ENODEV; + + return 0; +} + +/* + * Insert parsers for further node types here. + * + * Each parser takes a pointer to the @node and to the @parent (will be NULL + * for the first device path node). If a device corresponding to @node was + * found below @parent, its reference count should be incremented and the + * device returned in @child. + * + * The return value should be 0 on success or a negative int on failure. + * The special return values 0x01 (EFI_DEV_END_INSTANCE) and 0xFF + * (EFI_DEV_END_ENTIRE) signal the end of the device path, only + * parse_end_path() is supposed to return this. + * + * Be sure to validate the node length and contents before commencing the + * search for a device. + */ + +static long __init parse_end_path(struct efi_dev_path *node, + struct device *parent, struct device **child) +{ + if (node->length != 4) + return -EINVAL; + if (node->sub_type != EFI_DEV_END_INSTANCE && + node->sub_type != EFI_DEV_END_ENTIRE) + return -EINVAL; + if (!parent) + return -ENODEV; + + *child = get_device(parent); + return node->sub_type; +} + +/** + * efi_get_device_by_path - find device by EFI Device Path + * @node: EFI Device Path + * @len: maximum length of EFI Device Path in bytes + * + * Parse a series of EFI Device Path nodes at @node and find the corresponding + * device. If the device was found, its reference count is incremented and a + * pointer to it is returned. The caller needs to drop the reference with + * put_device() after use. The @node pointer is updated to point to the + * location immediately after the "End of Hardware Device Path" node. + * + * If another Device Path instance follows, @len is decremented by the number + * of bytes consumed. Otherwise @len is set to %0. + * + * If a Device Path node is malformed or its corresponding device is not found, + * @node is updated to point to this offending node and an ERR_PTR is returned. + * + * If @len is initially %0, the function returns %NULL. Thus, to iterate over + * all instances in a path, the following idiom may be used: + * + * while (!IS_ERR_OR_NULL(dev = efi_get_device_by_path(&node, &len))) { + * // do something with dev + * put_device(dev); + * } + * if (IS_ERR(dev)) + * // report error + * + * Devices can only be found if they're already instantiated. Most buses + * instantiate devices in the "subsys" initcall level, hence the earliest + * initcall level in which this function should be called is "fs". + * + * Returns the device on success or + * %ERR_PTR(-ENODEV) if no device was found, + * %ERR_PTR(-EINVAL) if a node is malformed or exceeds @len, + * %ERR_PTR(-ENOTSUPP) if support for a node type is not yet implemented. + */ +struct device * __init efi_get_device_by_path(struct efi_dev_path **node, + size_t *len) +{ + struct device *parent = NULL, *child; + long ret = 0; + + if (!*len) + return NULL; + + while (!ret) { + if (*len < 4 || *len < (*node)->length) + ret = -EINVAL; + else if ((*node)->type == EFI_DEV_ACPI && + (*node)->sub_type == EFI_DEV_BASIC_ACPI) + ret = parse_acpi_path(*node, parent, &child); + else if ((*node)->type == EFI_DEV_HW && + (*node)->sub_type == EFI_DEV_PCI) + ret = parse_pci_path(*node, parent, &child); + else if (((*node)->type == EFI_DEV_END_PATH || + (*node)->type == EFI_DEV_END_PATH2)) + ret = parse_end_path(*node, parent, &child); + else + ret = -ENOTSUPP; + + put_device(parent); + if (ret < 0) + return ERR_PTR(ret); + + parent = child; + *node = (void *)*node + (*node)->length; + *len -= (*node)->length; + } + + if (ret == EFI_DEV_END_ENTIRE) + *len = 0; + + return child; +} diff --git a/include/linux/efi.h b/include/linux/efi.h index f5a821d9b90c..261767212c47 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1148,6 +1148,26 @@ struct efi_generic_dev_path { u16 length; } __attribute ((packed)); +struct efi_dev_path { + u8 type; /* can be replaced with unnamed */ + u8 sub_type; /* struct efi_generic_dev_path; */ + u16 length; /* once we've moved to -std=c11 */ + union { + struct { + u32 hid; + u32 uid; + } acpi; + struct { + u8 fn; + u8 dev; + } pci; + }; +} __attribute ((packed)); + +#if IS_ENABLED(CONFIG_EFI_DEV_PATH_PARSER) +struct device *efi_get_device_by_path(struct efi_dev_path **node, size_t *len); +#endif + static inline void memrange_efi_to_native(u64 *addr, u64 *npages) { *npages = PFN_UP(*addr + (*npages< Date: Sat, 12 Nov 2016 21:32:36 +0000 Subject: x86/efi: Retrieve and assign Apple device properties MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Apple's EFI drivers supply device properties which are needed to support Macs optimally. They contain vital information which cannot be obtained any other way (e.g. Thunderbolt Device ROM). They're also used to convey the current device state so that OS drivers can pick up where EFI drivers left (e.g. GPU mode setting). There's an EFI driver dubbed "AAPL,PathProperties" which implements a per-device key/value store. Other EFI drivers populate it using a custom protocol. The macOS bootloader /System/Library/CoreServices/boot.efi retrieves the properties with the same protocol. The kernel extension AppleACPIPlatform.kext subsequently merges them into the I/O Kit registry (see ioreg(8)) where they can be queried by other kernel extensions and user space. This commit extends the efistub to retrieve the device properties before ExitBootServices is called. It assigns them to devices in an fs_initcall so that they can be queried with the API in . Note that the device properties will only be available if the kernel is booted with the efistub. Distros should adjust their installers to always use the efistub on Macs. grub with the "linux" directive will not work unless the functionality of this commit is duplicated in grub. (The "linuxefi" directive should work but is not included upstream as of this writing.) The custom protocol has GUID 91BD12FE-F6C3-44FB-A5B7-5122AB303AE0 and looks like this: typedef struct { unsigned long version; /* 0x10000 */ efi_status_t (*get) ( IN struct apple_properties_protocol *this, IN struct efi_dev_path *device, IN efi_char16_t *property_name, OUT void *buffer, IN OUT u32 *buffer_len); /* EFI_SUCCESS, EFI_NOT_FOUND, EFI_BUFFER_TOO_SMALL */ efi_status_t (*set) ( IN struct apple_properties_protocol *this, IN struct efi_dev_path *device, IN efi_char16_t *property_name, IN void *property_value, IN u32 property_value_len); /* allocates copies of property name and value */ /* EFI_SUCCESS, EFI_OUT_OF_RESOURCES */ efi_status_t (*del) ( IN struct apple_properties_protocol *this, IN struct efi_dev_path *device, IN efi_char16_t *property_name); /* EFI_SUCCESS, EFI_NOT_FOUND */ efi_status_t (*get_all) ( IN struct apple_properties_protocol *this, OUT void *buffer, IN OUT u32 *buffer_len); /* EFI_SUCCESS, EFI_BUFFER_TOO_SMALL */ } apple_properties_protocol; Thanks to Pedro Vilaça for this blog post which was helpful in reverse engineering Apple's EFI drivers and bootloader: https://reverse.put.as/2016/06/25/apple-efi-firmware-passwords-and-the-scbo-myth/ If someone at Apple is reading this, please note there's a memory leak in your implementation of the del() function as the property struct is freed but the name and value allocations are not. Neither the macOS bootloader nor Apple's EFI drivers check the protocol version, but we do to avoid breakage if it's ever changed. It's been the same since at least OS X 10.6 (2009). The get_all() function conveniently fills a buffer with all properties in marshalled form which can be passed to the kernel as a setup_data payload. The number of device properties is dynamic and can change between a first invocation of get_all() (to determine the buffer size) and a second invocation (to retrieve the actual buffer), hence the peculiar loop which does not finish until the buffer size settles. The macOS bootloader does the same. The setup_data payload is later on unmarshalled in an fs_initcall. The idea is that most buses instantiate devices in "subsys" initcall level and drivers are usually bound to these devices in "device" initcall level, so we assign the properties in-between, i.e. in "fs" initcall level. This assumes that devices to which properties pertain are instantiated from a "subsys" initcall or earlier. That should always be the case since on macOS, AppleACPIPlatformExpert::matchEFIDevicePath() only supports ACPI and PCI nodes and we've fully scanned those buses during "subsys" initcall level. The second assumption is that properties are only needed from a "device" initcall or later. Seems reasonable to me, but should this ever not work out, an alternative approach would be to store the property sets e.g. in a btree early during boot. Then whenever device_add() is called, an EFI Device Path would have to be constructed for the newly added device, and looked up in the btree. That way, the property set could be assigned to the device immediately on instantiation. And this would also work for devices instantiated in a deferred fashion. It seems like this approach would be more complicated and require more code. That doesn't seem justified without a specific use case. For comparison, the strategy on macOS is to assign properties to objects in the ACPI namespace (AppleACPIPlatformExpert::mergeEFIProperties()). That approach is definitely wrong as it fails for devices not present in the namespace: The NHI EFI driver supplies properties for attached Thunderbolt devices, yet on Macs with Thunderbolt 1 only one device level behind the host controller is described in the namespace. Consequently macOS cannot assign properties for chained devices. With Thunderbolt 2 they started to describe three device levels behind host controllers in the namespace but this grossly inflates the SSDT and still fails if the user daisy-chained more than three devices. We copy the property names and values from the setup_data payload to swappable virtual memory and afterwards make the payload available to the page allocator. This is just for the sake of good housekeeping, it wouldn't occupy a meaningful amount of physical memory (4444 bytes on my machine). Only the payload is freed, not the setup_data header since otherwise we'd break the list linkage and we cannot safely update the predecessor's ->next link because there's no locking for the list. The payload is currently not passed on to kexec'ed kernels, same for PCI ROMs retrieved by setup_efi_pci(). This can be added later if there is demand by amending setup_efi_state(). The payload can then no longer be made available to the page allocator of course. Tested-by: Lukas Wunner [MacBookPro9,1] Tested-by: Pierre Moreau [MacBookPro11,3] Signed-off-by: Lukas Wunner Signed-off-by: Matt Fleming Cc: Andreas Noever Cc: Ard Biesheuvel Cc: Linus Torvalds Cc: Pedro Vilaça Cc: Peter Jones Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: grub-devel@gnu.org Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20161112213237.8804-9-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar --- Documentation/kernel-parameters.txt | 5 + arch/x86/boot/compressed/eboot.c | 65 +++++++++ arch/x86/include/uapi/asm/bootparam.h | 1 + drivers/firmware/efi/Kconfig | 13 ++ drivers/firmware/efi/Makefile | 1 + drivers/firmware/efi/apple-properties.c | 248 ++++++++++++++++++++++++++++++++ include/linux/efi.h | 17 +++ 7 files changed, 350 insertions(+) create mode 100644 drivers/firmware/efi/apple-properties.c (limited to 'include/linux') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 37babf91f2cb..86a31dfc036e 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1062,6 +1062,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted. dscc4.setup= [NET] + dump_apple_properties [X86] + Dump name and content of EFI device properties on + x86 Macs. Useful for driver authors to determine + what data is available or for reverse-engineering. + dyndbg[="val"] [KNL,DYNAMIC_DEBUG] module.dyndbg[="val"] Enable debug messages at boot time. See diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index cc69e37548db..ff01c8fc76f7 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -537,6 +537,69 @@ free_handle: efi_call_early(free_pool, pci_handle); } +static void retrieve_apple_device_properties(struct boot_params *boot_params) +{ + efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID; + struct setup_data *data, *new; + efi_status_t status; + u32 size = 0; + void *p; + + status = efi_call_early(locate_protocol, &guid, NULL, &p); + if (status != EFI_SUCCESS) + return; + + if (efi_table_attr(apple_properties_protocol, version, p) != 0x10000) { + efi_printk(sys_table, "Unsupported properties proto version\n"); + return; + } + + efi_call_proto(apple_properties_protocol, get_all, p, NULL, &size); + if (!size) + return; + + do { + status = efi_call_early(allocate_pool, EFI_LOADER_DATA, + size + sizeof(struct setup_data), &new); + if (status != EFI_SUCCESS) { + efi_printk(sys_table, + "Failed to alloc mem for properties\n"); + return; + } + + status = efi_call_proto(apple_properties_protocol, get_all, p, + new->data, &size); + + if (status == EFI_BUFFER_TOO_SMALL) + efi_call_early(free_pool, new); + } while (status == EFI_BUFFER_TOO_SMALL); + + new->type = SETUP_APPLE_PROPERTIES; + new->len = size; + new->next = 0; + + data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data; + if (!data) + boot_params->hdr.setup_data = (unsigned long)new; + else { + while (data->next) + data = (struct setup_data *)(unsigned long)data->next; + data->next = (unsigned long)new; + } +} + +static void setup_quirks(struct boot_params *boot_params) +{ + efi_char16_t const apple[] = { 'A', 'p', 'p', 'l', 'e', 0 }; + efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long) + efi_table_attr(efi_system_table, fw_vendor, sys_table); + + if (!memcmp(fw_vendor, apple, sizeof(apple))) { + if (IS_ENABLED(CONFIG_APPLE_PROPERTIES)) + retrieve_apple_device_properties(boot_params); + } +} + static efi_status_t setup_uga32(void **uga_handle, unsigned long size, u32 *width, u32 *height) { @@ -1098,6 +1161,8 @@ struct boot_params *efi_main(struct efi_config *c, setup_efi_pci(boot_params); + setup_quirks(boot_params); + status = efi_call_early(allocate_pool, EFI_LOADER_DATA, sizeof(*gdt), (void **)&gdt); if (status != EFI_SUCCESS) { diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h index c18ce67495fa..b10bf319ed20 100644 --- a/arch/x86/include/uapi/asm/bootparam.h +++ b/arch/x86/include/uapi/asm/bootparam.h @@ -7,6 +7,7 @@ #define SETUP_DTB 2 #define SETUP_PCI 3 #define SETUP_EFI 4 +#define SETUP_APPLE_PROPERTIES 5 /* ram_size flags */ #define RAMDISK_IMAGE_START_MASK 0x07FF diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index 893fda48fcdd..2e78b0b96d74 100644 --- a/drivers/firmware/efi/Kconfig +++ b/drivers/firmware/efi/Kconfig @@ -129,6 +129,19 @@ config EFI_TEST Say Y here to enable the runtime services support via /dev/efi_test. If unsure, say N. +config APPLE_PROPERTIES + bool "Apple Device Properties" + depends on EFI_STUB && X86 + select EFI_DEV_PATH_PARSER + select UCS2_STRING + help + Retrieve properties from EFI on Apple Macs and assign them to + devices, allowing for improved support of Apple hardware. + Properties that would otherwise be missing include the + Thunderbolt Device ROM and GPU configuration data. + + If unsure, say Y if you have a Mac. Otherwise N. + endmenu config UEFI_CPER diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index 3e91ae31f9d1..ad67342313ed 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -22,6 +22,7 @@ obj-$(CONFIG_EFI_FAKE_MEMMAP) += fake_mem.o obj-$(CONFIG_EFI_BOOTLOADER_CONTROL) += efibc.o obj-$(CONFIG_EFI_TEST) += test/ obj-$(CONFIG_EFI_DEV_PATH_PARSER) += dev-path-parser.o +obj-$(CONFIG_APPLE_PROPERTIES) += apple-properties.o arm-obj-$(CONFIG_EFI) := arm-init.o arm-runtime.o obj-$(CONFIG_ARM) += $(arm-obj-y) diff --git a/drivers/firmware/efi/apple-properties.c b/drivers/firmware/efi/apple-properties.c new file mode 100644 index 000000000000..c473f4c5ca34 --- /dev/null +++ b/drivers/firmware/efi/apple-properties.c @@ -0,0 +1,248 @@ +/* + * apple-properties.c - EFI device properties on Macs + * Copyright (C) 2016 Lukas Wunner + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License (version 2) as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +#define pr_fmt(fmt) "apple-properties: " fmt + +#include +#include +#include +#include +#include +#include +#include + +static bool dump_properties __initdata; + +static int __init dump_properties_enable(char *arg) +{ + dump_properties = true; + return 0; +} + +__setup("dump_apple_properties", dump_properties_enable); + +struct dev_header { + u32 len; + u32 prop_count; + struct efi_dev_path path[0]; + /* + * followed by key/value pairs, each key and value preceded by u32 len, + * len includes itself, value may be empty (in which case its len is 4) + */ +}; + +struct properties_header { + u32 len; + u32 version; + u32 dev_count; + struct dev_header dev_header[0]; +}; + +static u8 one __initdata = 1; + +static void __init unmarshal_key_value_pairs(struct dev_header *dev_header, + struct device *dev, void *ptr, + struct property_entry entry[]) +{ + int i; + + for (i = 0; i < dev_header->prop_count; i++) { + int remaining = dev_header->len - (ptr - (void *)dev_header); + u32 key_len, val_len; + char *key; + + if (sizeof(key_len) > remaining) + break; + + key_len = *(typeof(key_len) *)ptr; + if (key_len + sizeof(val_len) > remaining || + key_len < sizeof(key_len) + sizeof(efi_char16_t) || + *(efi_char16_t *)(ptr + sizeof(key_len)) == 0) { + dev_err(dev, "invalid property name len at %#zx\n", + ptr - (void *)dev_header); + break; + } + + val_len = *(typeof(val_len) *)(ptr + key_len); + if (key_len + val_len > remaining || + val_len < sizeof(val_len)) { + dev_err(dev, "invalid property val len at %#zx\n", + ptr - (void *)dev_header + key_len); + break; + } + + /* 4 bytes to accommodate UTF-8 code points + null byte */ + key = kzalloc((key_len - sizeof(key_len)) * 4 + 1, GFP_KERNEL); + if (!key) { + dev_err(dev, "cannot allocate property name\n"); + break; + } + ucs2_as_utf8(key, ptr + sizeof(key_len), + key_len - sizeof(key_len)); + + entry[i].name = key; + entry[i].is_array = true; + entry[i].length = val_len - sizeof(val_len); + entry[i].pointer.raw_data = ptr + key_len + sizeof(val_len); + if (!entry[i].length) { + /* driver core doesn't accept empty properties */ + entry[i].length = 1; + entry[i].pointer.raw_data = &one; + } + + if (dump_properties) { + dev_info(dev, "property: %s\n", entry[i].name); + print_hex_dump(KERN_INFO, pr_fmt(), DUMP_PREFIX_OFFSET, + 16, 1, entry[i].pointer.raw_data, + entry[i].length, true); + } + + ptr += key_len + val_len; + } + + if (i != dev_header->prop_count) { + dev_err(dev, "got %d device properties, expected %u\n", i, + dev_header->prop_count); + print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET, + 16, 1, dev_header, dev_header->len, true); + return; + } + + dev_info(dev, "assigning %d device properties\n", i); +} + +static int __init unmarshal_devices(struct properties_header *properties) +{ + size_t offset = offsetof(struct properties_header, dev_header[0]); + + while (offset + sizeof(struct dev_header) < properties->len) { + struct dev_header *dev_header = (void *)properties + offset; + struct property_entry *entry = NULL; + struct device *dev; + size_t len; + int ret, i; + void *ptr; + + if (offset + dev_header->len > properties->len || + dev_header->len <= sizeof(*dev_header)) { + pr_err("invalid len in dev_header at %#zx\n", offset); + return -EINVAL; + } + + ptr = dev_header->path; + len = dev_header->len - sizeof(*dev_header); + + dev = efi_get_device_by_path((struct efi_dev_path **)&ptr, &len); + if (IS_ERR(dev)) { + pr_err("device path parse error %ld at %#zx:\n", + PTR_ERR(dev), ptr - (void *)dev_header); + print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET, + 16, 1, dev_header, dev_header->len, true); + dev = NULL; + goto skip_device; + } + + entry = kcalloc(dev_header->prop_count + 1, sizeof(*entry), + GFP_KERNEL); + if (!entry) { + dev_err(dev, "cannot allocate properties\n"); + goto skip_device; + } + + unmarshal_key_value_pairs(dev_header, dev, ptr, entry); + if (!entry[0].name) + goto skip_device; + + ret = device_add_properties(dev, entry); /* makes deep copy */ + if (ret) + dev_err(dev, "error %d assigning properties\n", ret); + + for (i = 0; entry[i].name; i++) + kfree(entry[i].name); + +skip_device: + kfree(entry); + put_device(dev); + offset += dev_header->len; + } + + return 0; +} + +static int __init map_properties(void) +{ + struct properties_header *properties; + struct setup_data *data; + u32 data_len; + u64 pa_data; + int ret; + + if (!dmi_match(DMI_SYS_VENDOR, "Apple Inc.") && + !dmi_match(DMI_SYS_VENDOR, "Apple Computer, Inc.")) + return 0; + + pa_data = boot_params.hdr.setup_data; + while (pa_data) { + data = ioremap(pa_data, sizeof(*data)); + if (!data) { + pr_err("cannot map setup_data header\n"); + return -ENOMEM; + } + + if (data->type != SETUP_APPLE_PROPERTIES) { + pa_data = data->next; + iounmap(data); + continue; + } + + data_len = data->len; + iounmap(data); + + data = ioremap(pa_data, sizeof(*data) + data_len); + if (!data) { + pr_err("cannot map setup_data payload\n"); + return -ENOMEM; + } + + properties = (struct properties_header *)data->data; + if (properties->version != 1) { + pr_err("unsupported version:\n"); + print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET, + 16, 1, properties, data_len, true); + ret = -ENOTSUPP; + } else if (properties->len != data_len) { + pr_err("length mismatch, expected %u\n", data_len); + print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET, + 16, 1, properties, data_len, true); + ret = -EINVAL; + } else + ret = unmarshal_devices(properties); + + /* + * Can only free the setup_data payload but not its header + * to avoid breaking the chain of ->next pointers. + */ + data->len = 0; + iounmap(data); + free_bootmem_late(pa_data + sizeof(*data), data_len); + + return ret; + } + return 0; +} + +fs_initcall(map_properties); diff --git a/include/linux/efi.h b/include/linux/efi.h index 261767212c47..a07a476178cd 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -443,6 +443,22 @@ typedef struct { #define EFI_PCI_IO_ATTRIBUTE_VGA_PALETTE_IO_16 0x20000 #define EFI_PCI_IO_ATTRIBUTE_VGA_IO_16 0x40000 +typedef struct { + u32 version; + u32 get; + u32 set; + u32 del; + u32 get_all; +} apple_properties_protocol_32_t; + +typedef struct { + u64 version; + u64 get; + u64 set; + u64 del; + u64 get_all; +} apple_properties_protocol_64_t; + /* * Types and defines for EFI ResetSystem */ @@ -592,6 +608,7 @@ void efi_native_runtime_setup(void); #define EFI_RNG_ALGORITHM_RAW EFI_GUID(0xe43176d7, 0xb6e8, 0x4827, 0xb7, 0x84, 0x7f, 0xfd, 0xc4, 0xb6, 0x85, 0x61) #define EFI_MEMORY_ATTRIBUTES_TABLE_GUID EFI_GUID(0xdcfa911d, 0x26eb, 0x469f, 0xa2, 0x20, 0x38, 0xb7, 0xdc, 0x46, 0x12, 0x20) #define EFI_CONSOLE_OUT_DEVICE_GUID EFI_GUID(0xd3b36f2c, 0xd551, 0x11d4, 0x9a, 0x46, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d) +#define APPLE_PROPERTIES_PROTOCOL_GUID EFI_GUID(0x91bd12fe, 0xf6c3, 0x44fb, 0xa5, 0xb7, 0x51, 0x22, 0xab, 0x30, 0x3a, 0xe0) /* * This GUID is used to pass to the kernel proper the struct screen_info -- cgit v1.2.3