X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Fefivars.c;h=840e4e0c350cbbbfeb873375c19f783317f523ae;hp=d5cb88cff1504475ca3a1da9242ab25063a681eb;hb=46ba8aae2b82bc5c87ba347e6bf914ecd5e9d51e;hpb=e9cea16db6c3e3c371a2f9651a2eea3dd47022d2 diff --git a/src/shared/efivars.c b/src/shared/efivars.c index d5cb88cff..840e4e0c3 100644 --- a/src/shared/efivars.c +++ b/src/shared/efivars.c @@ -20,19 +20,25 @@ ***/ #include +#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) { +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) { +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; @@ -62,7 +68,7 @@ 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; @@ -85,7 +91,7 @@ int efi_get_variable(sd_id128_t vendor, const char *name, uint32_t *attribute, v ((char*) r)[st.st_size - 4 + 1] = 0; *value = r; - *size = (size_t) st.st_size; + *size = (size_t) st.st_size - 4; if (attribute) *attribute = a; @@ -93,24 +99,282 @@ int efi_get_variable(sd_id128_t vendor, const char *name, uint32_t *attribute, v return 0; } +int efi_get_variable_string(sd_id128_t vendor, const char *name, char **p) { + _cleanup_free_ void *s = NULL; + size_t ss; + 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) { + + 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_; + + char boot_id[9]; + _cleanup_free_ uint8_t *buf = NULL; + size_t l; + struct boot_option *header; + size_t title_size; + char *s = NULL; + char *p = NULL; + sd_id128_t p_uuid = SD_ID128_NULL; + int err; + + snprintf(boot_id, sizeof(boot_id), "Boot%04X", id); + err = efi_get_variable(EFI_VENDOR_GLOBAL, boot_id, NULL, (void **)&buf, &l); + if (err < 0) + return err; + 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; + + s = utf16_to_utf8(header->title, title_size); + if (!s) { + err = -ENOMEM; + goto err; + } + + 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 == 0x7f && dpath->sub_type == 0xff) + break; + + dnext += dpath->length; + + /* Type 0x04 – Media Device Path */ + if (dpath->type != 0x04) + continue; + + /* Sub-Type 1 – Hard Drive */ + if (dpath->sub_type == 0x01) { + /* 0x02 – GUID Partition Table */ + if (dpath->drive.mbr_type != 0x02) + continue; + + /* 0x02 – GUID signature */ + if (dpath->drive.signature_type != 0x02) + continue; + + efi_guid_to_id128(dpath->drive.signature, &p_uuid); + continue; + } + + /* Sub-Type 4 – File Path */ + if (dpath->sub_type == 0x04) { + p = utf16_to_utf8(dpath->path, dpath->length-4); + continue; + } + } + } + + if (title) + *title = s; + if (part_uuid) + *part_uuid = p_uuid; + if (path) + *path = p; + + return 0; +err: + free(s); + free(p); + return err; +} + +int efi_get_boot_order(uint16_t **order) { + void *buf; + size_t l; + int r; + + r = efi_get_variable(EFI_VENDOR_GLOBAL, "BootOrder", NULL, &buf, &l); + if (r < 0) + return r; + + if (l <= 0) { + free(buf); + return -ENOENT; + } + + if ((l % sizeof(uint16_t) > 0) || + (l / sizeof(uint16_t) > INT_MAX)) { + free(buf); + return -EINVAL; + } + + *order = buf; + return (int) (l / 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 -1; + + return id; +} + +static int cmp_uint16(const void *_a, const void *_b) { + const uint16_t *a = _a, *b = _b; + + if (*a < *b) + return -1; + if (*a > *b) + return 1; + + return 0; +} + +int efi_get_boot_options(uint16_t **options) { + _cleanup_closedir_ DIR *dir = NULL; + struct dirent *de; + uint16_t *list = NULL; + int count = 0, r; + + assert(options); + + dir = opendir("/sys/firmware/efi/efivars/"); + if (!dir) + return -errno; + + FOREACH_DIRENT(de, dir, r = -errno; goto fail) { + int id; + uint16_t *t; + + 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; + + t = realloc(list, (count + 1) * sizeof(uint16_t)); + if (!t) { + r = -ENOMEM; + goto fail; + } + + list = t; + list[count ++] = id; + } + + qsort(list, count, sizeof(uint16_t), cmp_uint16); + + *options = list; + return count; + +fail: + free(list); + return r; +} + 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; 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; @@ -183,22 +447,16 @@ int efi_get_boot_timestamps(const dual_timestamp *n, dual_timestamp *firmware, d } int efi_get_loader_device_part_uuid(sd_id128_t *u) { - _cleanup_free_ void *s = NULL; _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],