summaryrefslogtreecommitdiffstats
path: root/src/boot/efi/util.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/boot/efi/util.c')
-rw-r--r--src/boot/efi/util.c705
1 files changed, 705 insertions, 0 deletions
diff --git a/src/boot/efi/util.c b/src/boot/efi/util.c
new file mode 100644
index 0000000..e56ccfd
--- /dev/null
+++ b/src/boot/efi/util.c
@@ -0,0 +1,705 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "device-path-util.h"
+#include "memory-util-fundamental.h"
+#include "proto/device-path.h"
+#include "proto/simple-text-io.h"
+#include "ticks.h"
+#include "util.h"
+#include "version.h"
+
+EFI_STATUS efivar_set_raw(const EFI_GUID *vendor, const char16_t *name, const void *buf, size_t size, uint32_t flags) {
+ assert(vendor);
+ assert(name);
+ assert(buf || size == 0);
+
+ flags |= EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS;
+ return RT->SetVariable((char16_t *) name, (EFI_GUID *) vendor, flags, size, (void *) buf);
+}
+
+EFI_STATUS efivar_set(const EFI_GUID *vendor, const char16_t *name, const char16_t *value, uint32_t flags) {
+ assert(vendor);
+ assert(name);
+
+ return efivar_set_raw(vendor, name, value, value ? strsize16(value) : 0, flags);
+}
+
+EFI_STATUS efivar_set_uint_string(const EFI_GUID *vendor, const char16_t *name, size_t i, uint32_t flags) {
+ assert(vendor);
+ assert(name);
+
+ _cleanup_free_ char16_t *str = xasprintf("%zu", i);
+ return efivar_set(vendor, name, str, flags);
+}
+
+EFI_STATUS efivar_set_uint32_le(const EFI_GUID *vendor, const char16_t *name, uint32_t value, uint32_t flags) {
+ uint8_t buf[4];
+
+ assert(vendor);
+ assert(name);
+
+ buf[0] = (uint8_t)(value >> 0U & 0xFF);
+ buf[1] = (uint8_t)(value >> 8U & 0xFF);
+ buf[2] = (uint8_t)(value >> 16U & 0xFF);
+ buf[3] = (uint8_t)(value >> 24U & 0xFF);
+
+ return efivar_set_raw(vendor, name, buf, sizeof(buf), flags);
+}
+
+EFI_STATUS efivar_set_uint64_le(const EFI_GUID *vendor, const char16_t *name, uint64_t value, uint32_t flags) {
+ uint8_t buf[8];
+
+ assert(vendor);
+ assert(name);
+
+ buf[0] = (uint8_t)(value >> 0U & 0xFF);
+ buf[1] = (uint8_t)(value >> 8U & 0xFF);
+ buf[2] = (uint8_t)(value >> 16U & 0xFF);
+ buf[3] = (uint8_t)(value >> 24U & 0xFF);
+ buf[4] = (uint8_t)(value >> 32U & 0xFF);
+ buf[5] = (uint8_t)(value >> 40U & 0xFF);
+ buf[6] = (uint8_t)(value >> 48U & 0xFF);
+ buf[7] = (uint8_t)(value >> 56U & 0xFF);
+
+ return efivar_set_raw(vendor, name, buf, sizeof(buf), flags);
+}
+
+EFI_STATUS efivar_unset(const EFI_GUID *vendor, const char16_t *name, uint32_t flags) {
+ EFI_STATUS err;
+
+ assert(vendor);
+ assert(name);
+
+ /* We could be wiping a non-volatile variable here and the spec makes no guarantees that won't incur
+ * in an extra write (and thus wear out). So check and clear only if needed. */
+ err = efivar_get_raw(vendor, name, NULL, NULL);
+ if (err == EFI_SUCCESS)
+ return efivar_set_raw(vendor, name, NULL, 0, flags);
+
+ return err;
+}
+
+EFI_STATUS efivar_get(const EFI_GUID *vendor, const char16_t *name, char16_t **ret) {
+ _cleanup_free_ char16_t *buf = NULL;
+ EFI_STATUS err;
+ char16_t *val;
+ size_t size;
+
+ assert(vendor);
+ assert(name);
+
+ err = efivar_get_raw(vendor, name, (char **) &buf, &size);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ /* Make sure there are no incomplete characters in the buffer */
+ if ((size % sizeof(char16_t)) != 0)
+ return EFI_INVALID_PARAMETER;
+
+ if (!ret)
+ return EFI_SUCCESS;
+
+ /* Return buffer directly if it happens to be NUL terminated already */
+ if (size >= sizeof(char16_t) && buf[size / sizeof(char16_t) - 1] == 0) {
+ *ret = TAKE_PTR(buf);
+ return EFI_SUCCESS;
+ }
+
+ /* Make sure a terminating NUL is available at the end */
+ val = xmalloc(size + sizeof(char16_t));
+
+ memcpy(val, buf, size);
+ val[size / sizeof(char16_t) - 1] = 0; /* NUL terminate */
+
+ *ret = val;
+ return EFI_SUCCESS;
+}
+
+EFI_STATUS efivar_get_uint_string(const EFI_GUID *vendor, const char16_t *name, size_t *ret) {
+ _cleanup_free_ char16_t *val = NULL;
+ EFI_STATUS err;
+ uint64_t u;
+
+ assert(vendor);
+ assert(name);
+
+ err = efivar_get(vendor, name, &val);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ if (!parse_number16(val, &u, NULL) || u > SIZE_MAX)
+ return EFI_INVALID_PARAMETER;
+
+ if (ret)
+ *ret = u;
+ return EFI_SUCCESS;
+}
+
+EFI_STATUS efivar_get_uint32_le(const EFI_GUID *vendor, const char16_t *name, uint32_t *ret) {
+ _cleanup_free_ char *buf = NULL;
+ size_t size;
+ EFI_STATUS err;
+
+ assert(vendor);
+ assert(name);
+
+ err = efivar_get_raw(vendor, name, &buf, &size);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ if (size != sizeof(uint32_t))
+ return EFI_BUFFER_TOO_SMALL;
+
+ if (ret)
+ *ret = (uint32_t) buf[0] << 0U | (uint32_t) buf[1] << 8U | (uint32_t) buf[2] << 16U |
+ (uint32_t) buf[3] << 24U;
+
+ return EFI_SUCCESS;
+}
+
+EFI_STATUS efivar_get_uint64_le(const EFI_GUID *vendor, const char16_t *name, uint64_t *ret) {
+ _cleanup_free_ char *buf = NULL;
+ size_t size;
+ EFI_STATUS err;
+
+ assert(vendor);
+ assert(name);
+
+ err = efivar_get_raw(vendor, name, &buf, &size);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ if (size != sizeof(uint64_t))
+ return EFI_BUFFER_TOO_SMALL;
+
+ if (ret)
+ *ret = (uint64_t) buf[0] << 0U | (uint64_t) buf[1] << 8U | (uint64_t) buf[2] << 16U |
+ (uint64_t) buf[3] << 24U | (uint64_t) buf[4] << 32U | (uint64_t) buf[5] << 40U |
+ (uint64_t) buf[6] << 48U | (uint64_t) buf[7] << 56U;
+
+ return EFI_SUCCESS;
+}
+
+EFI_STATUS efivar_get_raw(const EFI_GUID *vendor, const char16_t *name, char **ret, size_t *ret_size) {
+ EFI_STATUS err;
+
+ assert(vendor);
+ assert(name);
+
+ size_t size = 0;
+ err = RT->GetVariable((char16_t *) name, (EFI_GUID *) vendor, NULL, &size, NULL);
+ if (err != EFI_BUFFER_TOO_SMALL)
+ return err;
+
+ _cleanup_free_ void *buf = xmalloc(size);
+ err = RT->GetVariable((char16_t *) name, (EFI_GUID *) vendor, NULL, &size, buf);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ if (ret)
+ *ret = TAKE_PTR(buf);
+ if (ret_size)
+ *ret_size = size;
+
+ return EFI_SUCCESS;
+}
+
+EFI_STATUS efivar_get_boolean_u8(const EFI_GUID *vendor, const char16_t *name, bool *ret) {
+ _cleanup_free_ char *b = NULL;
+ size_t size;
+ EFI_STATUS err;
+
+ assert(vendor);
+ assert(name);
+
+ err = efivar_get_raw(vendor, name, &b, &size);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ if (ret)
+ *ret = *b > 0;
+
+ return EFI_SUCCESS;
+}
+
+void efivar_set_time_usec(const EFI_GUID *vendor, const char16_t *name, uint64_t usec) {
+ assert(vendor);
+ assert(name);
+
+ if (usec == 0)
+ usec = time_usec();
+ if (usec == 0)
+ return;
+
+ _cleanup_free_ char16_t *str = xasprintf("%" PRIu64, usec);
+ efivar_set(vendor, name, str, 0);
+}
+
+void convert_efi_path(char16_t *path) {
+ assert(path);
+
+ for (size_t i = 0, fixed = 0;; i++) {
+ /* Fix device path node separator. */
+ path[fixed] = (path[i] == '/') ? '\\' : path[i];
+
+ /* Double '\' is not allowed in EFI file paths. */
+ if (fixed > 0 && path[fixed - 1] == '\\' && path[fixed] == '\\')
+ continue;
+
+ if (path[i] == '\0')
+ break;
+
+ fixed++;
+ }
+}
+
+char16_t *xstr8_to_path(const char *str8) {
+ assert(str8);
+ char16_t *path = xstr8_to_16(str8);
+ convert_efi_path(path);
+ return path;
+}
+
+static bool shall_be_whitespace(char16_t c) {
+ return c <= 0x20U || c == 0x7FU; /* All control characters + space */
+}
+
+char16_t* mangle_stub_cmdline(char16_t *cmdline) {
+ char16_t *p, *q, *e;
+
+ if (!cmdline)
+ return cmdline;
+
+ p = q = cmdline;
+
+ /* Skip initial whitespace */
+ while (shall_be_whitespace(*p))
+ p++;
+
+ /* Turn inner control characters into proper spaces */
+ for (e = p; *p != 0; p++) {
+ if (shall_be_whitespace(*p)) {
+ *(q++) = ' ';
+ continue;
+ }
+
+ *(q++) = *p;
+ e = q; /* remember last non-whitespace char */
+ }
+
+ /* Chop off trailing whitespace */
+ *e = 0;
+ return cmdline;
+}
+
+EFI_STATUS chunked_read(EFI_FILE *file, size_t *size, void *buf) {
+ EFI_STATUS err;
+
+ assert(file);
+ assert(size);
+ assert(buf);
+
+ /* This is a drop-in replacement for EFI_FILE->Read() with the same API behavior.
+ * Some broken firmwares cannot handle large file reads and will instead return
+ * an error. As a workaround, read such files in small chunks.
+ * Note that we cannot just try reading the whole file first on such firmware as
+ * that will permanently break the handle even if it is re-opened.
+ *
+ * https://github.com/systemd/systemd/issues/25911 */
+
+ if (*size == 0)
+ return EFI_SUCCESS;
+
+ size_t read = 0, remaining = *size;
+ while (remaining > 0) {
+ size_t chunk = MIN(1024U * 1024U, remaining);
+
+ err = file->Read(file, &chunk, (uint8_t *) buf + read);
+ if (err != EFI_SUCCESS)
+ return err;
+ if (chunk == 0)
+ /* Caller requested more bytes than are in file. */
+ break;
+
+ assert(chunk <= remaining);
+ read += chunk;
+ remaining -= chunk;
+ }
+
+ *size = read;
+ return EFI_SUCCESS;
+}
+
+EFI_STATUS file_read(EFI_FILE *dir, const char16_t *name, size_t off, size_t size, char **ret, size_t *ret_size) {
+ _cleanup_(file_closep) EFI_FILE *handle = NULL;
+ _cleanup_free_ char *buf = NULL;
+ EFI_STATUS err;
+
+ assert(dir);
+ assert(name);
+ assert(ret);
+
+ err = dir->Open(dir, &handle, (char16_t*) name, EFI_FILE_MODE_READ, 0ULL);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ if (size == 0) {
+ _cleanup_free_ EFI_FILE_INFO *info = NULL;
+
+ err = get_file_info(handle, &info, NULL);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ size = info->FileSize;
+ }
+
+ if (off > 0) {
+ err = handle->SetPosition(handle, off);
+ if (err != EFI_SUCCESS)
+ return err;
+ }
+
+ /* Allocate some extra bytes to guarantee the result is NUL-terminated for char and char16_t strings. */
+ size_t extra = size % sizeof(char16_t) + sizeof(char16_t);
+
+ buf = xmalloc(size + extra);
+ err = chunked_read(handle, &size, buf);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ /* Note that chunked_read() changes size to reflect the actual bytes read. */
+ memzero(buf + size, extra);
+
+ *ret = TAKE_PTR(buf);
+ if (ret_size)
+ *ret_size = size;
+
+ return err;
+}
+
+void print_at(size_t x, size_t y, size_t attr, const char16_t *str) {
+ assert(str);
+ ST->ConOut->SetCursorPosition(ST->ConOut, x, y);
+ ST->ConOut->SetAttribute(ST->ConOut, attr);
+ ST->ConOut->OutputString(ST->ConOut, (char16_t *) str);
+}
+
+void clear_screen(size_t attr) {
+ log_wait();
+ ST->ConOut->SetAttribute(ST->ConOut, attr);
+ ST->ConOut->ClearScreen(ST->ConOut);
+}
+
+void sort_pointer_array(
+ void **array,
+ size_t n_members,
+ compare_pointer_func_t compare) {
+
+ assert(array || n_members == 0);
+ assert(compare);
+
+ if (n_members <= 1)
+ return;
+
+ for (size_t i = 1; i < n_members; i++) {
+ size_t k;
+ void *entry = array[i];
+
+ for (k = i; k > 0; k--) {
+ if (compare(array[k - 1], entry) <= 0)
+ break;
+
+ array[k] = array[k - 1];
+ }
+
+ array[k] = entry;
+ }
+}
+
+EFI_STATUS get_file_info(EFI_FILE *handle, EFI_FILE_INFO **ret, size_t *ret_size) {
+ size_t size = EFI_FILE_INFO_MIN_SIZE;
+ _cleanup_free_ EFI_FILE_INFO *fi = NULL;
+ EFI_STATUS err;
+
+ assert(handle);
+ assert(ret);
+
+ fi = xmalloc(size);
+ err = handle->GetInfo(handle, MAKE_GUID_PTR(EFI_FILE_INFO), &size, fi);
+ if (err == EFI_BUFFER_TOO_SMALL) {
+ free(fi);
+ fi = xmalloc(size); /* GetInfo tells us the required size, let's use that now */
+ err = handle->GetInfo(handle, MAKE_GUID_PTR(EFI_FILE_INFO), &size, fi);
+ }
+
+ if (err != EFI_SUCCESS)
+ return err;
+
+ *ret = TAKE_PTR(fi);
+
+ if (ret_size)
+ *ret_size = size;
+
+ return EFI_SUCCESS;
+}
+
+EFI_STATUS readdir(
+ EFI_FILE *handle,
+ EFI_FILE_INFO **buffer,
+ size_t *buffer_size) {
+
+ EFI_STATUS err;
+ size_t sz;
+
+ assert(handle);
+ assert(buffer);
+ assert(buffer_size);
+
+ /* buffer/buffer_size are both in and output parameters. Should be zero-initialized initially, and
+ * the specified buffer needs to be freed by caller, after final use. */
+
+ if (!*buffer) {
+ sz = EFI_FILE_INFO_MIN_SIZE;
+ *buffer = xmalloc(sz);
+ *buffer_size = sz;
+ } else
+ sz = *buffer_size;
+
+ err = handle->Read(handle, &sz, *buffer);
+ if (err == EFI_BUFFER_TOO_SMALL) {
+ free(*buffer);
+ *buffer = xmalloc(sz);
+ *buffer_size = sz;
+ err = handle->Read(handle, &sz, *buffer);
+ }
+ if (err != EFI_SUCCESS)
+ return err;
+
+ if (sz == 0) {
+ /* End of directory */
+ free(*buffer);
+ *buffer = NULL;
+ *buffer_size = 0;
+ }
+
+ return EFI_SUCCESS;
+}
+
+bool is_ascii(const char16_t *f) {
+ if (!f)
+ return false;
+
+ for (; *f != 0; f++)
+ if (*f > 127)
+ return false;
+
+ return true;
+}
+
+char16_t **strv_free(char16_t **v) {
+ if (!v)
+ return NULL;
+
+ for (char16_t **i = v; *i; i++)
+ free(*i);
+
+ free(v);
+ return NULL;
+}
+
+EFI_STATUS open_directory(
+ EFI_FILE *root,
+ const char16_t *path,
+ EFI_FILE **ret) {
+
+ _cleanup_(file_closep) EFI_FILE *dir = NULL;
+ _cleanup_free_ EFI_FILE_INFO *file_info = NULL;
+ EFI_STATUS err;
+
+ assert(root);
+
+ /* Opens a file, and then verifies it is actually a directory */
+
+ err = root->Open(root, &dir, (char16_t *) path, EFI_FILE_MODE_READ, 0);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ err = get_file_info(dir, &file_info, NULL);
+ if (err != EFI_SUCCESS)
+ return err;
+ if (!FLAGS_SET(file_info->Attribute, EFI_FILE_DIRECTORY))
+ return EFI_LOAD_ERROR;
+
+ *ret = TAKE_PTR(dir);
+ return EFI_SUCCESS;
+}
+
+uint64_t get_os_indications_supported(void) {
+ uint64_t osind;
+ EFI_STATUS err;
+
+ /* Returns the supported OS indications. If we can't acquire it, returns a zeroed out mask, i.e. no
+ * supported features. */
+
+ err = efivar_get_uint64_le(MAKE_GUID_PTR(EFI_GLOBAL_VARIABLE), u"OsIndicationsSupported", &osind);
+ if (err != EFI_SUCCESS)
+ return 0;
+
+ return osind;
+}
+
+__attribute__((noinline)) void notify_debugger(const char *identity, volatile bool wait) {
+#ifdef EFI_DEBUG
+ printf("%s@%p %s\n", identity, __executable_start, GIT_VERSION);
+ if (wait)
+ printf("Waiting for debugger to attach...\n");
+
+ /* This is a poor programmer's breakpoint to wait until a debugger
+ * has attached to us. Just "set variable wait = 0" or "return" to continue. */
+ while (wait)
+ /* Prefer asm based stalling so that gdb has a source location to present. */
+# if defined(__i386__) || defined(__x86_64__)
+ asm volatile("pause");
+# elif defined(__aarch64__)
+ asm volatile("wfi");
+# else
+ BS->Stall(5000);
+# endif
+#endif
+}
+
+#if defined(__i386__) || defined(__x86_64__)
+static uint8_t inb(uint16_t port) {
+ uint8_t value;
+ asm volatile("inb %1, %0" : "=a"(value) : "Nd"(port));
+ return value;
+}
+
+static void outb(uint16_t port, uint8_t value) {
+ asm volatile("outb %0, %1" : : "a"(value), "Nd"(port));
+}
+
+void beep(unsigned beep_count) {
+ enum {
+ PITCH = 500,
+ BEEP_DURATION_USEC = 100 * 1000,
+ WAIT_DURATION_USEC = 400 * 1000,
+
+ PIT_FREQUENCY = 0x1234dd,
+ SPEAKER_CONTROL_PORT = 0x61,
+ SPEAKER_ON_MASK = 0x03,
+ TIMER_PORT_MAGIC = 0xB6,
+ TIMER_CONTROL_PORT = 0x43,
+ TIMER_CONTROL2_PORT = 0x42,
+ };
+
+ /* Set frequency. */
+ uint32_t counter = PIT_FREQUENCY / PITCH;
+ outb(TIMER_CONTROL_PORT, TIMER_PORT_MAGIC);
+ outb(TIMER_CONTROL2_PORT, counter & 0xFF);
+ outb(TIMER_CONTROL2_PORT, (counter >> 8) & 0xFF);
+
+ uint8_t value = inb(SPEAKER_CONTROL_PORT);
+
+ while (beep_count > 0) {
+ /* Turn speaker on. */
+ value |= SPEAKER_ON_MASK;
+ outb(SPEAKER_CONTROL_PORT, value);
+
+ BS->Stall(BEEP_DURATION_USEC);
+
+ /* Turn speaker off. */
+ value &= ~SPEAKER_ON_MASK;
+ outb(SPEAKER_CONTROL_PORT, value);
+
+ beep_count--;
+ if (beep_count > 0)
+ BS->Stall(WAIT_DURATION_USEC);
+ }
+}
+#endif
+
+EFI_STATUS open_volume(EFI_HANDLE device, EFI_FILE **ret_file) {
+ EFI_STATUS err;
+ EFI_FILE *file;
+ EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *volume;
+
+ assert(ret_file);
+
+ err = BS->HandleProtocol(device, MAKE_GUID_PTR(EFI_SIMPLE_FILE_SYSTEM_PROTOCOL), (void **) &volume);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ err = volume->OpenVolume(volume, &file);
+ if (err != EFI_SUCCESS)
+ return err;
+
+ *ret_file = file;
+ return EFI_SUCCESS;
+}
+
+void *find_configuration_table(const EFI_GUID *guid) {
+ for (size_t i = 0; i < ST->NumberOfTableEntries; i++)
+ if (efi_guid_equal(&ST->ConfigurationTable[i].VendorGuid, guid))
+ return ST->ConfigurationTable[i].VendorTable;
+
+ return NULL;
+}
+
+static void remove_boot_count(char16_t *path) {
+ char16_t *prefix_end;
+ const char16_t *tail;
+ uint64_t ignored;
+
+ assert(path);
+
+ prefix_end = strchr16(path, '+');
+ if (!prefix_end)
+ return;
+
+ tail = prefix_end + 1;
+
+ if (!parse_number16(tail, &ignored, &tail))
+ return;
+
+ if (*tail == '-') {
+ ++tail;
+ if (!parse_number16(tail, &ignored, &tail))
+ return;
+ }
+
+ if (!IN_SET(*tail, '\0', '.'))
+ return;
+
+ strcpy16(prefix_end, tail);
+}
+
+char16_t *get_extra_dir(const EFI_DEVICE_PATH *file_path) {
+ if (!file_path)
+ return NULL;
+
+ /* A device path is allowed to have more than one file path node. If that is the case they are
+ * supposed to be concatenated. Unfortunately, the device path to text protocol simply converts the
+ * nodes individually and then combines those with the usual '/' for device path nodes. But this does
+ * not create a legal EFI file path that the file protocol can use. */
+
+ /* Make sure we really only got file paths. */
+ for (const EFI_DEVICE_PATH *node = file_path; !device_path_is_end(node);
+ node = device_path_next_node(node))
+ if (node->Type != MEDIA_DEVICE_PATH || node->SubType != MEDIA_FILEPATH_DP)
+ return NULL;
+
+ _cleanup_free_ char16_t *file_path_str = NULL;
+ if (device_path_to_str(file_path, &file_path_str) != EFI_SUCCESS)
+ return NULL;
+
+ convert_efi_path(file_path_str);
+ remove_boot_count(file_path_str);
+ return xasprintf("%ls.extra.d", file_path_str);
+}
+
+void *xmalloc(size_t size) {
+ void *p = NULL;
+ assert_se(BS->AllocatePool(EfiLoaderData, size, &p) == EFI_SUCCESS);
+ return p;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-30 12:33:51 +0000