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/* SPDX-License-Identifier: LGPL-2.1-or-later */
#include <efi.h>
#include <efilib.h>
#include "util.h"
#ifdef __x86_64__
UINT64 ticks_read(void) {
UINT64 a, d;
__asm__ volatile ("rdtsc" : "=a" (a), "=d" (d));
return (d << 32) | a;
}
#elif defined(__i386__)
UINT64 ticks_read(void) {
UINT64 val;
__asm__ volatile ("rdtsc" : "=A" (val));
return val;
}
#elif defined(__aarch64__)
UINT64 ticks_read(void) {
UINT64 val;
__asm__ volatile ("mrs %0, cntpct_el0" : "=r" (val));
return val;
}
#else
UINT64 ticks_read(void) {
UINT64 val = 1;
return val;
}
#endif
#if defined(__aarch64__)
UINT64 ticks_freq(void) {
UINT64 freq;
__asm__ volatile ("mrs %0, cntfrq_el0": "=r" (freq));
return freq;
}
#else
/* count TSC ticks during a millisecond delay */
UINT64 ticks_freq(void) {
UINT64 ticks_start, ticks_end;
ticks_start = ticks_read();
BS->Stall(1000);
ticks_end = ticks_read();
return (ticks_end - ticks_start) * 1000UL;
}
#endif
UINT64 time_usec(void) {
UINT64 ticks;
static UINT64 freq;
ticks = ticks_read();
if (ticks == 0)
return 0;
if (freq == 0) {
freq = ticks_freq();
if (freq == 0)
return 0;
}
return 1000UL * 1000UL * ticks / freq;
}
EFI_STATUS parse_boolean(const CHAR8 *v, BOOLEAN *b) {
assert(b);
if (!v)
return EFI_INVALID_PARAMETER;
if (strcmpa(v, (CHAR8 *)"1") == 0 ||
strcmpa(v, (CHAR8 *)"yes") == 0 ||
strcmpa(v, (CHAR8 *)"y") == 0 ||
strcmpa(v, (CHAR8 *)"true") == 0 ||
strcmpa(v, (CHAR8 *)"t") == 0 ||
strcmpa(v, (CHAR8 *)"on") == 0) {
*b = TRUE;
return EFI_SUCCESS;
}
if (strcmpa(v, (CHAR8 *)"0") == 0 ||
strcmpa(v, (CHAR8 *)"no") == 0 ||
strcmpa(v, (CHAR8 *)"n") == 0 ||
strcmpa(v, (CHAR8 *)"false") == 0 ||
strcmpa(v, (CHAR8 *)"f") == 0 ||
strcmpa(v, (CHAR8 *)"off") == 0) {
*b = FALSE;
return EFI_SUCCESS;
}
return EFI_INVALID_PARAMETER;
}
EFI_STATUS efivar_set_raw(const EFI_GUID *vendor, const CHAR16 *name, const void *buf, UINTN size, UINT32 flags) {
assert(vendor);
assert(name);
assert(buf || size == 0);
flags |= EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS;
return RT->SetVariable((CHAR16 *) name, (EFI_GUID *) vendor, flags, size, (void *) buf);
}
EFI_STATUS efivar_set(const EFI_GUID *vendor, const CHAR16 *name, const CHAR16 *value, UINT32 flags) {
assert(vendor);
assert(name);
return efivar_set_raw(vendor, name, value, value ? StrSize(value) : 0, flags);
}
EFI_STATUS efivar_set_uint_string(const EFI_GUID *vendor, const CHAR16 *name, UINTN i, UINT32 flags) {
CHAR16 str[32];
assert(vendor);
assert(name);
SPrint(str, ELEMENTSOF(str), L"%u", i);
return efivar_set(vendor, name, str, flags);
}
EFI_STATUS efivar_set_uint32_le(const EFI_GUID *vendor, const CHAR16 *name, UINT32 value, UINT32 flags) {
UINT8 buf[4];
assert(vendor);
assert(name);
buf[0] = (UINT8)(value >> 0U & 0xFF);
buf[1] = (UINT8)(value >> 8U & 0xFF);
buf[2] = (UINT8)(value >> 16U & 0xFF);
buf[3] = (UINT8)(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 *name, UINT64 value, UINT32 flags) {
UINT8 buf[8];
assert(vendor);
assert(name);
buf[0] = (UINT8)(value >> 0U & 0xFF);
buf[1] = (UINT8)(value >> 8U & 0xFF);
buf[2] = (UINT8)(value >> 16U & 0xFF);
buf[3] = (UINT8)(value >> 24U & 0xFF);
buf[4] = (UINT8)(value >> 32U & 0xFF);
buf[5] = (UINT8)(value >> 40U & 0xFF);
buf[6] = (UINT8)(value >> 48U & 0xFF);
buf[7] = (UINT8)(value >> 56U & 0xFF);
return efivar_set_raw(vendor, name, buf, sizeof(buf), flags);
}
EFI_STATUS efivar_get(const EFI_GUID *vendor, const CHAR16 *name, CHAR16 **value) {
_cleanup_freepool_ CHAR16 *buf = NULL;
EFI_STATUS err;
CHAR16 *val;
UINTN size;
assert(vendor);
assert(name);
err = efivar_get_raw(vendor, name, (CHAR8**)&buf, &size);
if (EFI_ERROR(err))
return err;
/* Make sure there are no incomplete characters in the buffer */
if ((size % sizeof(CHAR16)) != 0)
return EFI_INVALID_PARAMETER;
if (!value)
return EFI_SUCCESS;
/* Return buffer directly if it happens to be NUL terminated already */
if (size >= sizeof(CHAR16) && buf[size / sizeof(CHAR16) - 1] == 0) {
*value = TAKE_PTR(buf);
return EFI_SUCCESS;
}
/* Make sure a terminating NUL is available at the end */
val = xallocate_pool(size + sizeof(CHAR16));
CopyMem(val, buf, size);
val[size / sizeof(CHAR16) - 1] = 0; /* NUL terminate */
*value = val;
return EFI_SUCCESS;
}
EFI_STATUS efivar_get_uint_string(const EFI_GUID *vendor, const CHAR16 *name, UINTN *i) {
_cleanup_freepool_ CHAR16 *val = NULL;
EFI_STATUS err;
assert(vendor);
assert(name);
assert(i);
err = efivar_get(vendor, name, &val);
if (!EFI_ERROR(err))
*i = Atoi(val);
return err;
}
EFI_STATUS efivar_get_uint32_le(const EFI_GUID *vendor, const CHAR16 *name, UINT32 *ret) {
_cleanup_freepool_ CHAR8 *buf = NULL;
UINTN size;
EFI_STATUS err;
assert(vendor);
assert(name);
err = efivar_get_raw(vendor, name, &buf, &size);
if (!EFI_ERROR(err) && ret) {
if (size != sizeof(UINT32))
return EFI_BUFFER_TOO_SMALL;
*ret = (UINT32) buf[0] << 0U | (UINT32) buf[1] << 8U | (UINT32) buf[2] << 16U |
(UINT32) buf[3] << 24U;
}
return err;
}
EFI_STATUS efivar_get_uint64_le(const EFI_GUID *vendor, const CHAR16 *name, UINT64 *ret) {
_cleanup_freepool_ CHAR8 *buf = NULL;
UINTN size;
EFI_STATUS err;
assert(vendor);
assert(name);
err = efivar_get_raw(vendor, name, &buf, &size);
if (!EFI_ERROR(err) && ret) {
if (size != sizeof(UINT64))
return EFI_BUFFER_TOO_SMALL;
*ret = (UINT64) buf[0] << 0U | (UINT64) buf[1] << 8U | (UINT64) buf[2] << 16U |
(UINT64) buf[3] << 24U | (UINT64) buf[4] << 32U | (UINT64) buf[5] << 40U |
(UINT64) buf[6] << 48U | (UINT64) buf[7] << 56U;
}
return err;
}
EFI_STATUS efivar_get_raw(const EFI_GUID *vendor, const CHAR16 *name, CHAR8 **buffer, UINTN *size) {
_cleanup_freepool_ CHAR8 *buf = NULL;
UINTN l;
EFI_STATUS err;
assert(vendor);
assert(name);
l = sizeof(CHAR16 *) * EFI_MAXIMUM_VARIABLE_SIZE;
buf = xallocate_pool(l);
err = RT->GetVariable((CHAR16 *) name, (EFI_GUID *) vendor, NULL, &l, buf);
if (!EFI_ERROR(err)) {
if (buffer)
*buffer = TAKE_PTR(buf);
if (size)
*size = l;
}
return err;
}
EFI_STATUS efivar_get_boolean_u8(const EFI_GUID *vendor, const CHAR16 *name, BOOLEAN *ret) {
_cleanup_freepool_ CHAR8 *b = NULL;
UINTN size;
EFI_STATUS err;
assert(vendor);
assert(name);
assert(ret);
err = efivar_get_raw(vendor, name, &b, &size);
if (!EFI_ERROR(err))
*ret = *b > 0;
return err;
}
void efivar_set_time_usec(const EFI_GUID *vendor, const CHAR16 *name, UINT64 usec) {
CHAR16 str[32];
assert(vendor);
assert(name);
if (usec == 0)
usec = time_usec();
if (usec == 0)
return;
SPrint(str, ELEMENTSOF(str), L"%ld", usec);
efivar_set(vendor, name, str, 0);
}
static INTN utf8_to_16(const CHAR8 *stra, CHAR16 *c) {
CHAR16 unichar;
UINTN len;
assert(stra);
assert(c);
if (!(stra[0] & 0x80))
len = 1;
else if ((stra[0] & 0xe0) == 0xc0)
len = 2;
else if ((stra[0] & 0xf0) == 0xe0)
len = 3;
else if ((stra[0] & 0xf8) == 0xf0)
len = 4;
else if ((stra[0] & 0xfc) == 0xf8)
len = 5;
else if ((stra[0] & 0xfe) == 0xfc)
len = 6;
else
return -1;
switch (len) {
case 1:
unichar = stra[0];
break;
case 2:
unichar = stra[0] & 0x1f;
break;
case 3:
unichar = stra[0] & 0x0f;
break;
case 4:
unichar = stra[0] & 0x07;
break;
case 5:
unichar = stra[0] & 0x03;
break;
case 6:
unichar = stra[0] & 0x01;
break;
}
for (UINTN i = 1; i < len; i++) {
if ((stra[i] & 0xc0) != 0x80)
return -1;
unichar <<= 6;
unichar |= stra[i] & 0x3f;
}
*c = unichar;
return len;
}
CHAR16 *xstra_to_str(const CHAR8 *stra) {
UINTN strlen;
UINTN len;
UINTN i;
CHAR16 *str;
assert(stra);
len = strlena(stra);
str = xnew(CHAR16, len + 1);
strlen = 0;
i = 0;
while (i < len) {
INTN utf8len;
utf8len = utf8_to_16(stra + i, str + strlen);
if (utf8len <= 0) {
/* invalid utf8 sequence, skip the garbage */
i++;
continue;
}
strlen++;
i += utf8len;
}
str[strlen] = '\0';
return str;
}
CHAR16 *xstra_to_path(const CHAR8 *stra) {
CHAR16 *str;
UINTN strlen;
UINTN len;
UINTN i;
assert(stra);
len = strlena(stra);
str = xnew(CHAR16, len + 2);
str[0] = '\\';
strlen = 1;
i = 0;
while (i < len) {
INTN utf8len;
utf8len = utf8_to_16(stra + i, str + strlen);
if (utf8len <= 0) {
/* invalid utf8 sequence, skip the garbage */
i++;
continue;
}
if (str[strlen] == '/')
str[strlen] = '\\';
if (str[strlen] == '\\' && str[strlen-1] == '\\') {
/* skip double slashes */
i += utf8len;
continue;
}
strlen++;
i += utf8len;
}
str[strlen] = '\0';
return str;
}
CHAR8 *strchra(const CHAR8 *s, CHAR8 c) {
if (!s)
return NULL;
do {
if (*s == c)
return (CHAR8*) s;
} while (*s++);
return NULL;
}
EFI_STATUS file_read(EFI_FILE *dir, const CHAR16 *name, UINTN off, UINTN size, CHAR8 **ret, UINTN *ret_size) {
_cleanup_(file_closep) EFI_FILE *handle = NULL;
_cleanup_freepool_ CHAR8 *buf = NULL;
EFI_STATUS err;
assert(dir);
assert(name);
assert(ret);
err = dir->Open(dir, &handle, (CHAR16*) name, EFI_FILE_MODE_READ, 0ULL);
if (EFI_ERROR(err))
return err;
if (size == 0) {
_cleanup_freepool_ EFI_FILE_INFO *info = NULL;
err = get_file_info_harder(handle, &info, NULL);
if (EFI_ERROR(err))
return err;
size = info->FileSize;
}
if (off > 0) {
err = handle->SetPosition(handle, off);
if (EFI_ERROR(err))
return err;
}
/* Allocate some extra bytes to guarantee the result is NUL-terminated for CHAR8 and CHAR16 strings. */
UINTN extra = size % sizeof(CHAR16) + sizeof(CHAR16);
buf = xallocate_pool(size + extra);
err = handle->Read(handle, &size, buf);
if (EFI_ERROR(err))
return err;
/* Note that handle->Read() changes size to reflect the actually bytes read. */
ZeroMem(buf + size, extra);
*ret = TAKE_PTR(buf);
if (ret_size)
*ret_size = size;
return err;
}
void log_error_stall(const CHAR16 *fmt, ...) {
va_list args;
assert(fmt);
INT32 attr = ST->ConOut->Mode->Attribute;
ST->ConOut->SetAttribute(ST->ConOut, EFI_LIGHTRED|EFI_BACKGROUND_BLACK);
if (ST->ConOut->Mode->CursorColumn > 0)
Print(L"\n");
va_start(args, fmt);
VPrint(fmt, args);
va_end(args);
Print(L"\n");
ST->ConOut->SetAttribute(ST->ConOut, attr);
/* Give the user a chance to see the message. */
BS->Stall(3 * 1000 * 1000);
}
EFI_STATUS log_oom(void) {
log_error_stall(L"Out of memory.");
return EFI_OUT_OF_RESOURCES;
}
void print_at(UINTN x, UINTN y, UINTN attr, const CHAR16 *str) {
assert(str);
ST->ConOut->SetCursorPosition(ST->ConOut, x, y);
ST->ConOut->SetAttribute(ST->ConOut, attr);
ST->ConOut->OutputString(ST->ConOut, (CHAR16*)str);
}
void clear_screen(UINTN attr) {
ST->ConOut->SetAttribute(ST->ConOut, attr);
ST->ConOut->ClearScreen(ST->ConOut);
}
void sort_pointer_array(
void **array,
UINTN n_members,
compare_pointer_func_t compare) {
assert(array || n_members == 0);
assert(compare);
if (n_members <= 1)
return;
for (UINTN i = 1; i < n_members; i++) {
UINTN 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_harder(
EFI_FILE *handle,
EFI_FILE_INFO **ret,
UINTN *ret_size) {
UINTN size = offsetof(EFI_FILE_INFO, FileName) + 256;
_cleanup_freepool_ EFI_FILE_INFO *fi = NULL;
EFI_STATUS err;
assert(handle);
assert(ret);
/* A lot like LibFileInfo() but with useful error propagation */
fi = xallocate_pool(size);
err = handle->GetInfo(handle, &GenericFileInfo, &size, fi);
if (err == EFI_BUFFER_TOO_SMALL) {
FreePool(fi);
fi = xallocate_pool(size); /* GetInfo tells us the required size, let's use that now */
err = handle->GetInfo(handle, &GenericFileInfo, &size, fi);
}
if (EFI_ERROR(err))
return err;
*ret = TAKE_PTR(fi);
if (ret_size)
*ret_size = size;
return EFI_SUCCESS;
}
EFI_STATUS readdir_harder(
EFI_FILE *handle,
EFI_FILE_INFO **buffer,
UINTN *buffer_size) {
EFI_STATUS err;
UINTN 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) {
/* Some broken firmware violates the EFI spec by still advancing the readdir
* position when returning EFI_BUFFER_TOO_SMALL, effectively skipping over any files when
* the buffer was too small. Therefore, start with a buffer that should handle FAT32 max
* file name length.
* As a side effect, most readdir_harder() calls will now be slightly faster. */
sz = sizeof(EFI_FILE_INFO) + 256 * sizeof(CHAR16);
*buffer = xallocate_pool(sz);
*buffer_size = sz;
} else
sz = *buffer_size;
err = handle->Read(handle, &sz, *buffer);
if (err == EFI_BUFFER_TOO_SMALL) {
FreePool(*buffer);
*buffer = xallocate_pool(sz);
*buffer_size = sz;
err = handle->Read(handle, &sz, *buffer);
}
if (EFI_ERROR(err))
return err;
if (sz == 0) {
/* End of directory */
FreePool(*buffer);
*buffer = NULL;
*buffer_size = 0;
}
return EFI_SUCCESS;
}
UINTN strnlena(const CHAR8 *p, UINTN maxlen) {
UINTN c;
if (!p)
return 0;
for (c = 0; c < maxlen; c++)
if (p[c] == 0)
break;
return c;
}
INTN strncasecmpa(const CHAR8 *a, const CHAR8 *b, UINTN maxlen) {
if (!a || !b)
return CMP(a, b);
while (maxlen > 0) {
CHAR8 ca = *a, cb = *b;
if (ca >= 'A' && ca <= 'Z')
ca += 'a' - 'A';
if (cb >= 'A' && cb <= 'Z')
cb += 'a' - 'A';
if (!ca || ca != cb)
return ca - cb;
a++;
b++;
maxlen--;
}
return 0;
}
CHAR8 *xstrndup8(const CHAR8 *p, UINTN sz) {
CHAR8 *n;
/* Following efilib's naming scheme this function would be called strndupa(), but we already have a
* function named like this in userspace, and it does something different there, hence to minimize
* confusion, let's pick a different name here */
assert(p || sz == 0);
sz = strnlena(p, sz);
n = xallocate_pool(sz + 1);
if (sz > 0)
CopyMem(n, p, sz);
n[sz] = 0;
return n;
}
BOOLEAN is_ascii(const CHAR16 *f) {
if (!f)
return FALSE;
for (; *f != 0; f++)
if (*f > 127)
return FALSE;
return TRUE;
}
CHAR16 **strv_free(CHAR16 **v) {
if (!v)
return NULL;
for (CHAR16 **i = v; *i; i++)
FreePool(*i);
FreePool(v);
return NULL;
}
EFI_STATUS open_directory(
EFI_FILE *root,
const CHAR16 *path,
EFI_FILE **ret) {
_cleanup_(file_closep) EFI_FILE *dir = NULL;
_cleanup_freepool_ 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*) path, EFI_FILE_MODE_READ, 0ULL);
if (EFI_ERROR(err))
return err;
err = get_file_info_harder(dir, &file_info, NULL);
if (EFI_ERROR(err))
return err;
if (!FLAGS_SET(file_info->Attribute, EFI_FILE_DIRECTORY))
return EFI_LOAD_ERROR;
*ret = TAKE_PTR(dir);
return EFI_SUCCESS;
}
UINT64 get_os_indications_supported(void) {
UINT64 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(EFI_GLOBAL_GUID, L"OsIndicationsSupported", &osind);
if (EFI_ERROR(err))
return 0;
return osind;
}
#ifdef EFI_DEBUG
__attribute__((noinline)) void debug_break(void) {
/* 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. */
volatile BOOLEAN wait = TRUE;
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 inline UINT8 inb(UINT16 port) {
UINT8 value;
asm volatile("inb %1, %0" : "=a"(value) : "Nd"(port));
return value;
}
static inline void outb(UINT16 port, UINT8 value) {
asm volatile("outb %0, %1" : : "a"(value), "Nd"(port));
}
void beep(UINTN 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 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 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
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