X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Fefivars.c;h=70b6ce1cc707c7b8c7768ca4bd6e35dd4d9b1301;hb=726c6b6b3d82b8cdf0087375d4f95e4df4013c62;hp=f1abee34c24468da2792c9e56befd2fac44138c5;hpb=5dbe9f539849a9404a92858e5b70b36408812fbd;p=elogind.git diff --git a/src/shared/efivars.c b/src/shared/efivars.c index f1abee34c..70b6ce1cc 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; @@ -93,6 +99,245 @@ 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)); +} + +int efi_get_boot_options(uint16_t **options) { + _cleanup_closedir_ DIR *dir = NULL; + struct dirent *de; + uint16_t *list = NULL; + int count = 0; + + assert(options); + + dir = opendir("/sys/firmware/efi/efivars/"); + if (!dir) + return -errno; + + while ((de = readdir(dir))) { + size_t n; + int a, b, c, d; + uint16_t *t; + + if (strncmp(de->d_name, "Boot", 4) != 0) + continue; + + n = strlen(de->d_name); + if (n != 45) + continue; + + if (strcmp(de->d_name + 8, "-8be4df61-93ca-11d2-aa0d-00e098032b8c") != 0) + continue; + + a = de->d_name[4]; + b = de->d_name[5]; + c = de->d_name[6]; + d = de->d_name[7]; + + if (!isdigit(a) || !isdigit(b) || !isdigit(c) || !isdigit(d)) + continue; + + t = realloc(list, (count + 1) * sizeof(uint16_t)); + if (!t) { + free(list); + return -ENOMEM; + } + + list = t; + list[count ++] = (a - '0') * 1000 + (b - '0') * 100 + (c - '0') * 10 + (d - '0'); + + } + + *options = list; + 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; @@ -126,11 +371,11 @@ static int get_boot_usec(usec_t *firmware, usec_t *loader) { assert(firmware); assert(loader); - r = read_usec(EFI_VENDOR_LOADER, "LoaderTimeInitUsec", &x); + r = read_usec(EFI_VENDOR_LOADER, "LoaderTimeInitUSec", &x); if (r < 0) return r; - r = read_usec(EFI_VENDOR_LOADER, "LoaderTimeExecUsec", &y); + r = read_usec(EFI_VENDOR_LOADER, "LoaderTimeExecUSec", &y); if (r < 0) return r;