X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Fefivars.c;h=20067c601adb41d205c2a4eda7c8e7fbfbc7c333;hp=d5cb88cff1504475ca3a1da9242ab25063a681eb;hb=d8d5781c1eb031477670facc132e198f8fddd56c;hpb=e9cea16db6c3e3c371a2f9651a2eea3dd47022d2 diff --git a/src/shared/efivars.c b/src/shared/efivars.c index d5cb88cff..20067c601 100644 --- a/src/shared/efivars.c +++ b/src/shared/efivars.c @@ -20,25 +20,92 @@ ***/ #include +#include #include #include "util.h" #include "utf8.h" #include "efivars.h" -#define EFI_VENDOR_LOADER SD_ID128_MAKE(4a,67,b0,82,0a,4c,41,cf,b6,c7,44,0b,29,bb,8c,4f) - -bool is_efiboot(void) { +#ifdef ENABLE_EFI + +#define LOAD_OPTION_ACTIVE 0x00000001 +#define MEDIA_DEVICE_PATH 0x04 +#define MEDIA_HARDDRIVE_DP 0x01 +#define MEDIA_FILEPATH_DP 0x04 +#define SIGNATURE_TYPE_GUID 0x02 +#define MBR_TYPE_EFI_PARTITION_TABLE_HEADER 0x02 +#define END_DEVICE_PATH_TYPE 0x7f +#define END_ENTIRE_DEVICE_PATH_SUBTYPE 0xff + +struct boot_option { + uint32_t attr; + uint16_t path_len; + uint16_t title[]; +} _packed_; + +struct drive_path { + uint32_t part_nr; + uint64_t part_start; + uint64_t part_size; + char signature[16]; + uint8_t mbr_type; + uint8_t signature_type; +} _packed_; + +struct device_path { + uint8_t type; + uint8_t sub_type; + uint16_t length; + union { + uint16_t path[0]; + struct drive_path drive; + }; +} _packed_; + +bool is_efi_boot(void) { return access("/sys/firmware/efi", F_OK) >= 0; } -int efi_get_variable(sd_id128_t vendor, const char *name, uint32_t *attribute, void **value, size_t *size) { +static int read_flag(const char *varname) { + int r; + _cleanup_free_ void *v = NULL; + size_t s; + uint8_t b; + + r = efi_get_variable(EFI_VENDOR_GLOBAL, varname, NULL, &v, &s); + if (r < 0) + return r; + + if (s != 1) + return -EINVAL; + + b = *(uint8_t *)v; + r = b > 0; + return r; +} + +int is_efi_secure_boot(void) { + return read_flag("SecureBoot"); +} + +int is_efi_secure_boot_setup_mode(void) { + return read_flag("SetupMode"); +} + +int efi_get_variable( + sd_id128_t vendor, + const char *name, + uint32_t *attribute, + void **value, + size_t *size) { + _cleanup_close_ int fd = -1; _cleanup_free_ char *p = NULL; uint32_t a; ssize_t n; struct stat st; - void *r; + _cleanup_free_ void *buf = NULL; assert(name); assert(value); @@ -62,30 +129,27 @@ int efi_get_variable(sd_id128_t vendor, const char *name, uint32_t *attribute, v n = read(fd, &a, sizeof(a)); if (n < 0) - return (int) n; + return -errno; if (n != sizeof(a)) return -EIO; - r = malloc(st.st_size - 4 + 2); - if (!r) + buf = malloc(st.st_size - 4 + 2); + if (!buf) return -ENOMEM; - n = read(fd, r, (size_t) st.st_size - 4); - if (n < 0) { - free(r); - return (int) -n; - } - if (n != (ssize_t) st.st_size - 4) { - free(r); + n = read(fd, buf, (size_t) st.st_size - 4); + if (n < 0) + return -errno; + if (n != (ssize_t) st.st_size - 4) return -EIO; - } /* Always NUL terminate (2 bytes, to protect UTF-16) */ - ((char*) r)[st.st_size - 4] = 0; - ((char*) r)[st.st_size - 4 + 1] = 0; + ((char*) buf)[st.st_size - 4] = 0; + ((char*) buf)[st.st_size - 4 + 1] = 0; - *value = r; - *size = (size_t) st.st_size; + *value = buf; + buf = NULL; + *size = (size_t) st.st_size - 4; if (attribute) *attribute = a; @@ -93,24 +157,403 @@ int efi_get_variable(sd_id128_t vendor, const char *name, uint32_t *attribute, v return 0; } +int efi_set_variable( + sd_id128_t vendor, + const char *name, + const void *value, + size_t size) { + + struct var { + uint32_t attr; + char buf[]; + } _packed_ * _cleanup_free_ buf = NULL; + _cleanup_free_ char *p = NULL; + _cleanup_close_ int fd = -1; + + assert(name); + + if (asprintf(&p, + "/sys/firmware/efi/efivars/%s-%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", + name, SD_ID128_FORMAT_VAL(vendor)) < 0) + return -ENOMEM; + + if (size == 0) { + if (unlink(p) < 0) + return -errno; + return 0; + } + + fd = open(p, O_WRONLY|O_CREAT|O_NOCTTY|O_CLOEXEC, 0644); + if (fd < 0) + return -errno; + + buf = malloc(sizeof(uint32_t) + size); + if (!buf) + return -ENOMEM; + + buf->attr = EFI_VARIABLE_NON_VOLATILE|EFI_VARIABLE_BOOTSERVICE_ACCESS|EFI_VARIABLE_RUNTIME_ACCESS; + memcpy(buf->buf, value, size); + + return loop_write(fd, buf, sizeof(uint32_t) + size, false); +} + +int efi_get_variable_string(sd_id128_t vendor, const char *name, char **p) { + _cleanup_free_ void *s = NULL; + size_t ss = 0; + int r; + char *x; + + r = efi_get_variable(vendor, name, NULL, &s, &ss); + if (r < 0) + return r; + + x = utf16_to_utf8(s, ss); + if (!x) + return -ENOMEM; + + *p = x; + return 0; +} + +static size_t utf16_size(const uint16_t *s) { + size_t l = 0; + + while (s[l] > 0) + l++; + + return (l+1) * sizeof(uint16_t); +} + +static void efi_guid_to_id128(const void *guid, sd_id128_t *id128) { + struct uuid { + uint32_t u1; + uint16_t u2; + uint16_t u3; + uint8_t u4[8]; + } _packed_; + const struct uuid *uuid = guid; + + id128->bytes[0] = (uuid->u1 >> 24) & 0xff; + id128->bytes[1] = (uuid->u1 >> 16) & 0xff; + id128->bytes[2] = (uuid->u1 >> 8) & 0xff; + id128->bytes[3] = (uuid->u1) & 0xff; + id128->bytes[4] = (uuid->u2 >> 8) & 0xff; + id128->bytes[5] = (uuid->u2) & 0xff; + id128->bytes[6] = (uuid->u3 >> 8) & 0xff; + id128->bytes[7] = (uuid->u3) & 0xff; + memcpy(&id128->bytes[8], uuid->u4, sizeof(uuid->u4)); +} + +int efi_get_boot_option( + uint16_t id, + char **title, + sd_id128_t *part_uuid, + char **path, + bool *active) { + + char boot_id[9]; + _cleanup_free_ uint8_t *buf = NULL; + size_t l; + struct boot_option *header; + size_t title_size; + _cleanup_free_ char *s = NULL, *p = NULL; + sd_id128_t p_uuid = SD_ID128_NULL; + int r; + + xsprintf(boot_id, "Boot%04X", id); + r = efi_get_variable(EFI_VENDOR_GLOBAL, boot_id, NULL, (void **)&buf, &l); + if (r < 0) + return r; + if (l < sizeof(struct boot_option)) + return -ENOENT; + + header = (struct boot_option *)buf; + title_size = utf16_size(header->title); + if (title_size > l - offsetof(struct boot_option, title)) + return -EINVAL; + + if (title) { + s = utf16_to_utf8(header->title, title_size); + if (!s) + return -ENOMEM; + } + + if (header->path_len > 0) { + uint8_t *dbuf; + size_t dnext; + + dbuf = buf + offsetof(struct boot_option, title) + title_size; + dnext = 0; + while (dnext < header->path_len) { + struct device_path *dpath; + + dpath = (struct device_path *)(dbuf + dnext); + if (dpath->length < 4) + break; + + /* Type 0x7F – End of Hardware Device Path, Sub-Type 0xFF – End Entire Device Path */ + if (dpath->type == END_DEVICE_PATH_TYPE && dpath->sub_type == END_ENTIRE_DEVICE_PATH_SUBTYPE) + break; + + dnext += dpath->length; + + /* Type 0x04 – Media Device Path */ + if (dpath->type != MEDIA_DEVICE_PATH) + continue; + + /* Sub-Type 1 – Hard Drive */ + if (dpath->sub_type == MEDIA_HARDDRIVE_DP) { + /* 0x02 – GUID Partition Table */ + if (dpath->drive.mbr_type != MBR_TYPE_EFI_PARTITION_TABLE_HEADER) + continue; + + /* 0x02 – GUID signature */ + if (dpath->drive.signature_type != SIGNATURE_TYPE_GUID) + continue; + + if (part_uuid) + efi_guid_to_id128(dpath->drive.signature, &p_uuid); + continue; + } + + /* Sub-Type 4 – File Path */ + if (dpath->sub_type == MEDIA_FILEPATH_DP && !p && path) { + p = utf16_to_utf8(dpath->path, dpath->length-4); + efi_tilt_backslashes(p); + continue; + } + } + } + + if (title) { + *title = s; + s = NULL; + } + if (part_uuid) + *part_uuid = p_uuid; + if (path) { + *path = p; + p = NULL; + } + if (active) + *active = !!(header->attr & LOAD_OPTION_ACTIVE); + + return 0; +} + +static void to_utf16(uint16_t *dest, const char *src) { + int i; + + for (i = 0; src[i] != '\0'; i++) + dest[i] = src[i]; + dest[i] = '\0'; +} + +struct guid { + uint32_t u1; + uint16_t u2; + uint16_t u3; + uint8_t u4[8]; +} _packed_; + +static void id128_to_efi_guid(sd_id128_t id, void *guid) { + struct guid *uuid = guid; + + uuid->u1 = id.bytes[0] << 24 | id.bytes[1] << 16 | id.bytes[2] << 8 | id.bytes[3]; + uuid->u2 = id.bytes[4] << 8 | id.bytes[5]; + uuid->u3 = id.bytes[6] << 8 | id.bytes[7]; + memcpy(uuid->u4, id.bytes+8, sizeof(uuid->u4)); +} + +static uint16_t *tilt_slashes(uint16_t *s) { + uint16_t *p; + + for (p = s; *p; p++) + if (*p == '/') + *p = '\\'; + + return s; +} + +char *efi_tilt_backslashes(char *s) { + char *p; + + for (p = s; *p; p++) + if (*p == '\\') + *p = '/'; + + return s; +} + +int efi_add_boot_option(uint16_t id, const char *title, + uint32_t part, uint64_t pstart, uint64_t psize, + sd_id128_t part_uuid, const char *path) { + char boot_id[9]; + size_t size; + size_t title_len; + size_t path_len; + struct boot_option *option; + struct device_path *devicep; + _cleanup_free_ char *buf = NULL; + + title_len = (strlen(title)+1) * 2; + path_len = (strlen(path)+1) * 2; + + buf = calloc(sizeof(struct boot_option) + title_len + + sizeof(struct drive_path) + + sizeof(struct device_path) + path_len, 1); + if (!buf) + return -ENOMEM; + + /* header */ + option = (struct boot_option *)buf; + option->attr = LOAD_OPTION_ACTIVE; + option->path_len = offsetof(struct device_path, drive) + sizeof(struct drive_path) + + offsetof(struct device_path, path) + path_len + + offsetof(struct device_path, path); + to_utf16(option->title, title); + size = offsetof(struct boot_option, title) + title_len; + + /* partition info */ + devicep = (struct device_path *)(buf + size); + devicep->type = MEDIA_DEVICE_PATH; + devicep->sub_type = MEDIA_HARDDRIVE_DP; + devicep->length = offsetof(struct device_path, drive) + sizeof(struct drive_path); + devicep->drive.part_nr = part; + devicep->drive.part_start = pstart; + devicep->drive.part_size = psize; + devicep->drive.signature_type = SIGNATURE_TYPE_GUID; + devicep->drive.mbr_type = MBR_TYPE_EFI_PARTITION_TABLE_HEADER; + id128_to_efi_guid(part_uuid, devicep->drive.signature); + size += devicep->length; + + /* path to loader */ + devicep = (struct device_path *)(buf + size); + devicep->type = MEDIA_DEVICE_PATH; + devicep->sub_type = MEDIA_FILEPATH_DP; + devicep->length = offsetof(struct device_path, path) + path_len; + to_utf16(devicep->path, path); + tilt_slashes(devicep->path); + size += devicep->length; + + /* end of path */ + devicep = (struct device_path *)(buf + size); + devicep->type = END_DEVICE_PATH_TYPE; + devicep->sub_type = END_ENTIRE_DEVICE_PATH_SUBTYPE; + devicep->length = offsetof(struct device_path, path); + size += devicep->length; + + xsprintf(boot_id, "Boot%04X", id); + return efi_set_variable(EFI_VENDOR_GLOBAL, boot_id, buf, size); +} + +int efi_remove_boot_option(uint16_t id) { + char boot_id[9]; + + xsprintf(boot_id, "Boot%04X", id); + return efi_set_variable(EFI_VENDOR_GLOBAL, boot_id, NULL, 0); +} + +int efi_get_boot_order(uint16_t **order) { + _cleanup_free_ void *buf = NULL; + size_t l; + int r; + + r = efi_get_variable(EFI_VENDOR_GLOBAL, "BootOrder", NULL, &buf, &l); + if (r < 0) + return r; + + if (l <= 0) + return -ENOENT; + + if (l % sizeof(uint16_t) > 0 || + l / sizeof(uint16_t) > INT_MAX) + return -EINVAL; + + *order = buf; + buf = NULL; + return (int) (l / sizeof(uint16_t)); +} + +int efi_set_boot_order(uint16_t *order, size_t n) { + return efi_set_variable(EFI_VENDOR_GLOBAL, "BootOrder", order, n * sizeof(uint16_t)); +} + +static int boot_id_hex(const char s[4]) { + int i; + int id = 0; + + for (i = 0; i < 4; i++) + if (s[i] >= '0' && s[i] <= '9') + id |= (s[i] - '0') << (3 - i) * 4; + else if (s[i] >= 'A' && s[i] <= 'F') + id |= (s[i] - 'A' + 10) << (3 - i) * 4; + else + return -EINVAL; + + return id; +} + +static int cmp_uint16(const void *_a, const void *_b) { + const uint16_t *a = _a, *b = _b; + + return (int)*a - (int)*b; +} + +int efi_get_boot_options(uint16_t **options) { + _cleanup_closedir_ DIR *dir = NULL; + struct dirent *de; + _cleanup_free_ uint16_t *list = NULL; + size_t alloc = 0; + int count = 0; + + assert(options); + + dir = opendir("/sys/firmware/efi/efivars/"); + if (!dir) + return -errno; + + FOREACH_DIRENT(de, dir, return -errno) { + int id; + + if (strncmp(de->d_name, "Boot", 4) != 0) + continue; + + if (strlen(de->d_name) != 45) + continue; + + if (strcmp(de->d_name + 8, "-8be4df61-93ca-11d2-aa0d-00e098032b8c") != 0) + continue; + + id = boot_id_hex(de->d_name + 4); + if (id < 0) + continue; + + if (!GREEDY_REALLOC(list, alloc, count + 1)) + return -ENOMEM; + + list[count++] = id; + } + + qsort_safe(list, count, sizeof(uint16_t), cmp_uint16); + + *options = list; + list = NULL; + return count; +} + static int read_usec(sd_id128_t vendor, const char *name, usec_t *u) { - _cleanup_free_ void *i = NULL; _cleanup_free_ char *j = NULL; - size_t is; int r; - uint64_t x; + uint64_t x = 0; assert(name); assert(u); - r = efi_get_variable(EFI_VENDOR_LOADER, name, NULL, &i, &is); + r = efi_get_variable_string(EFI_VENDOR_LOADER, name, &j); if (r < 0) return r; - j = utf16_to_utf8(i, is); - if (!j) - return -ENOMEM; - r = safe_atou64(j, &x); if (r < 0) return r; @@ -119,7 +562,7 @@ static int read_usec(sd_id128_t vendor, const char *name, usec_t *u) { return 0; } -static int get_boot_usec(usec_t *firmware, usec_t *loader) { +int efi_loader_get_boot_usec(usec_t *firmware, usec_t *loader) { uint64_t x, y; int r; @@ -146,59 +589,14 @@ static int get_boot_usec(usec_t *firmware, usec_t *loader) { return 0; } -int efi_get_boot_timestamps(const dual_timestamp *n, dual_timestamp *firmware, dual_timestamp *loader) { - usec_t x, y, a; - int r; - dual_timestamp _n; - - assert(firmware); - assert(loader); - - if (!n) { - dual_timestamp_get(&_n); - n = &_n; - } - - r = get_boot_usec(&x, &y); - if (r < 0) - return r; - - /* Let's convert this to timestamps where the firmware - * began/loader began working. To make this more confusing: - * since usec_t is unsigned and the kernel's monotonic clock - * begins at kernel initialization we'll actually initialize - * the monotonic timestamps here as negative of the actual - * value. */ - - firmware->monotonic = y; - loader->monotonic = y - x; - - a = n->monotonic + firmware->monotonic; - firmware->realtime = n->realtime > a ? n->realtime - a : 0; - - a = n->monotonic + loader->monotonic; - loader->realtime = n->realtime > a ? n->realtime - a : 0; - - return 0; -} - -int efi_get_loader_device_part_uuid(sd_id128_t *u) { - _cleanup_free_ void *s = NULL; +int efi_loader_get_device_part_uuid(sd_id128_t *u) { _cleanup_free_ char *p = NULL; - size_t ss; int r, parsed[16]; - unsigned i; - assert(u); - - r = efi_get_variable(EFI_VENDOR_LOADER, "LoaderDevicePartUUID", NULL, &s, &ss); + r = efi_get_variable_string(EFI_VENDOR_LOADER, "LoaderDevicePartUUID", &p); if (r < 0) return r; - p = utf16_to_utf8(s, ss); - if (!p) - return -ENOMEM; - if (sscanf(p, "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", &parsed[0], &parsed[1], &parsed[2], &parsed[3], &parsed[4], &parsed[5], &parsed[6], &parsed[7], @@ -206,8 +604,14 @@ int efi_get_loader_device_part_uuid(sd_id128_t *u) { &parsed[12], &parsed[13], &parsed[14], &parsed[15]) != 16) return -EIO; - for (i = 0; i < ELEMENTSOF(parsed); i++) - u->bytes[i] = parsed[i]; + if (u) { + unsigned i; + + for (i = 0; i < ELEMENTSOF(parsed); i++) + u->bytes[i] = parsed[i]; + } return 0; } + +#endif