diff options
Diffstat (limited to 'lib/efi_loader/efi_variable.c')
-rw-r--r-- | lib/efi_loader/efi_variable.c | 666 |
1 files changed, 562 insertions, 104 deletions
diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c index fe2f264591..adb78470f2 100644 --- a/lib/efi_loader/efi_variable.c +++ b/lib/efi_loader/efi_variable.c @@ -10,8 +10,14 @@ #include <env_internal.h> #include <hexdump.h> #include <malloc.h> +#include <rtc.h> #include <search.h> +#include <linux/compat.h> #include <u-boot/crc.h> +#include "../lib/crypto/pkcs7_parser.h" + +const efi_guid_t efi_guid_cert_type_pkcs7 = EFI_CERT_TYPE_PKCS7_GUID; +static bool efi_secure_boot; #define READ_ONLY BIT(31) @@ -106,9 +112,10 @@ static const char *prefix(const char *str, const char *prefix) * * @str: value of U-Boot variable * @attrp: pointer to UEFI attributes + * @timep: pointer to time attribute * Return: pointer to remainder of U-Boot variable value */ -static const char *parse_attr(const char *str, u32 *attrp) +static const char *parse_attr(const char *str, u32 *attrp, u64 *timep) { u32 attr = 0; char sep = '{'; @@ -131,6 +138,12 @@ static const char *parse_attr(const char *str, u32 *attrp) attr |= EFI_VARIABLE_BOOTSERVICE_ACCESS; } else if ((s = prefix(str, "run"))) { attr |= EFI_VARIABLE_RUNTIME_ACCESS; + } else if ((s = prefix(str, "time="))) { + attr |= EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS; + hex2bin((u8 *)timep, s, sizeof(*timep)); + s += sizeof(*timep) * 2; + } else if (*str == '}') { + break; } else { printf("invalid attribute: %s\n", str); break; @@ -148,48 +161,291 @@ static const char *parse_attr(const char *str, u32 *attrp) } /** - * efi_get_variable() - retrieve value of a UEFI variable + * efi_secure_boot_enabled - return if secure boot is enabled or not * - * This function implements the GetVariable runtime service. + * Return: true if enabled, false if disabled + */ +bool efi_secure_boot_enabled(void) +{ + return efi_secure_boot; +} + +#ifdef CONFIG_EFI_SECURE_BOOT +static u8 pkcs7_hdr[] = { + /* SEQUENCE */ + 0x30, 0x82, 0x05, 0xc7, + /* OID: pkcs7-signedData */ + 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x07, 0x02, + /* Context Structured? */ + 0xa0, 0x82, 0x05, 0xb8, +}; + +/** + * efi_variable_parse_signature - parse a signature in variable + * @buf: Pointer to variable's value + * @buflen: Length of @buf * - * See the Unified Extensible Firmware Interface (UEFI) specification for - * details. + * Parse a signature embedded in variable's value and instantiate + * a pkcs7_message structure. Since pkcs7_parse_message() accepts only + * pkcs7's signedData, some header needed be prepended for correctly + * parsing authentication data, particularly for variable's. * - * @variable_name: name of the variable - * @vendor: vendor GUID - * @attributes: attributes of the variable - * @data_size: size of the buffer to which the variable value is copied - * @data: buffer to which the variable value is copied - * Return: status code + * Return: Pointer to pkcs7_message structure on success, NULL on error */ -efi_status_t EFIAPI efi_get_variable(u16 *variable_name, - const efi_guid_t *vendor, u32 *attributes, - efi_uintn_t *data_size, void *data) +static struct pkcs7_message *efi_variable_parse_signature(const void *buf, + size_t buflen) +{ + u8 *ebuf; + size_t ebuflen, len; + struct pkcs7_message *msg; + + /* + * This is the best assumption to check if the binary is + * already in a form of pkcs7's signedData. + */ + if (buflen > sizeof(pkcs7_hdr) && + !memcmp(&((u8 *)buf)[4], &pkcs7_hdr[4], 11)) { + msg = pkcs7_parse_message(buf, buflen); + goto out; + } + + /* + * Otherwise, we should add a dummy prefix sequence for pkcs7 + * message parser to be able to process. + * NOTE: EDK2 also uses similar hack in WrapPkcs7Data() + * in CryptoPkg/Library/BaseCryptLib/Pk/CryptPkcs7VerifyCommon.c + * TODO: + * The header should be composed in a more refined manner. + */ + debug("Makeshift prefix added to authentication data\n"); + ebuflen = sizeof(pkcs7_hdr) + buflen; + if (ebuflen <= 0x7f) { + debug("Data is too short\n"); + return NULL; + } + + ebuf = malloc(ebuflen); + if (!ebuf) { + debug("Out of memory\n"); + return NULL; + } + + memcpy(ebuf, pkcs7_hdr, sizeof(pkcs7_hdr)); + memcpy(ebuf + sizeof(pkcs7_hdr), buf, buflen); + len = ebuflen - 4; + ebuf[2] = (len >> 8) & 0xff; + ebuf[3] = len & 0xff; + len = ebuflen - 0x13; + ebuf[0x11] = (len >> 8) & 0xff; + ebuf[0x12] = len & 0xff; + + msg = pkcs7_parse_message(ebuf, ebuflen); + + free(ebuf); + +out: + if (IS_ERR(msg)) + return NULL; + + return msg; +} + +/** + * efi_variable_authenticate - authenticate a variable + * @variable: Variable name in u16 + * @vendor: Guid of variable + * @data_size: Size of @data + * @data: Pointer to variable's value + * @given_attr: Attributes to be given at SetVariable() + * @env_attr: Attributes that an existing variable holds + * @time: signed time that an existing variable holds + * + * Called by efi_set_variable() to verify that the input is correct. + * Will replace the given data pointer with another that points to + * the actual data to store in the internal memory. + * On success, @data and @data_size will be replaced with variable's + * actual data, excluding authentication data, and its size, and variable's + * attributes and signed time will also be returned in @env_attr and @time, + * respectively. + * + * Return: EFI_SUCCESS on success, status code (negative) on error + */ +static efi_status_t efi_variable_authenticate(u16 *variable, + const efi_guid_t *vendor, + efi_uintn_t *data_size, + const void **data, u32 given_attr, + u32 *env_attr, u64 *time) +{ + const struct efi_variable_authentication_2 *auth; + struct efi_signature_store *truststore, *truststore2; + struct pkcs7_message *var_sig; + struct efi_image_regions *regs; + struct efi_time timestamp; + struct rtc_time tm; + u64 new_time; + efi_status_t ret; + + var_sig = NULL; + truststore = NULL; + truststore2 = NULL; + regs = NULL; + ret = EFI_SECURITY_VIOLATION; + + if (*data_size < sizeof(struct efi_variable_authentication_2)) + goto err; + + /* authentication data */ + auth = *data; + if (*data_size < (sizeof(auth->time_stamp) + + auth->auth_info.hdr.dwLength)) + goto err; + + if (guidcmp(&auth->auth_info.cert_type, &efi_guid_cert_type_pkcs7)) + goto err; + + *data += sizeof(auth->time_stamp) + auth->auth_info.hdr.dwLength; + *data_size -= (sizeof(auth->time_stamp) + + auth->auth_info.hdr.dwLength); + + memcpy(×tamp, &auth->time_stamp, sizeof(timestamp)); + memset(&tm, 0, sizeof(tm)); + tm.tm_year = timestamp.year; + tm.tm_mon = timestamp.month; + tm.tm_mday = timestamp.day; + tm.tm_hour = timestamp.hour; + tm.tm_min = timestamp.minute; + tm.tm_sec = timestamp.second; + new_time = rtc_mktime(&tm); + + if (!efi_secure_boot_enabled()) { + /* finished checking */ + *time = new_time; + return EFI_SUCCESS; + } + + if (new_time <= *time) + goto err; + + /* data to be digested */ + regs = calloc(sizeof(*regs) + sizeof(struct image_region) * 5, 1); + if (!regs) + goto err; + regs->max = 5; + efi_image_region_add(regs, (uint8_t *)variable, + (uint8_t *)variable + + u16_strlen(variable) * sizeof(u16), 1); + efi_image_region_add(regs, (uint8_t *)vendor, + (uint8_t *)vendor + sizeof(*vendor), 1); + efi_image_region_add(regs, (uint8_t *)&given_attr, + (uint8_t *)&given_attr + sizeof(given_attr), 1); + efi_image_region_add(regs, (uint8_t *)×tamp, + (uint8_t *)×tamp + sizeof(timestamp), 1); + efi_image_region_add(regs, (uint8_t *)*data, + (uint8_t *)*data + *data_size, 1); + + /* variable's signature list */ + if (auth->auth_info.hdr.dwLength < sizeof(auth->auth_info)) + goto err; + var_sig = efi_variable_parse_signature(auth->auth_info.cert_data, + auth->auth_info.hdr.dwLength + - sizeof(auth->auth_info)); + if (IS_ERR(var_sig)) { + debug("Parsing variable's signature failed\n"); + var_sig = NULL; + goto err; + } + + /* signature database used for authentication */ + if (u16_strcmp(variable, L"PK") == 0 || + u16_strcmp(variable, L"KEK") == 0) { + /* with PK */ + truststore = efi_sigstore_parse_sigdb(L"PK"); + if (!truststore) + goto err; + } else if (u16_strcmp(variable, L"db") == 0 || + u16_strcmp(variable, L"dbx") == 0) { + /* with PK and KEK */ + truststore = efi_sigstore_parse_sigdb(L"KEK"); + truststore2 = efi_sigstore_parse_sigdb(L"PK"); + + if (!truststore) { + if (!truststore2) + goto err; + + truststore = truststore2; + truststore2 = NULL; + } + } else { + /* TODO: support private authenticated variables */ + goto err; + } + + /* verify signature */ + if (efi_signature_verify_with_sigdb(regs, var_sig, truststore, NULL)) { + debug("Verified\n"); + } else { + if (truststore2 && + efi_signature_verify_with_sigdb(regs, var_sig, + truststore2, NULL)) { + debug("Verified\n"); + } else { + debug("Verifying variable's signature failed\n"); + goto err; + } + } + + /* finished checking */ + *time = rtc_mktime(&tm); + ret = EFI_SUCCESS; + +err: + efi_sigstore_free(truststore); + efi_sigstore_free(truststore2); + pkcs7_free_message(var_sig); + free(regs); + + return ret; +} +#else +static efi_status_t efi_variable_authenticate(u16 *variable, + const efi_guid_t *vendor, + efi_uintn_t *data_size, + const void **data, u32 given_attr, + u32 *env_attr, u64 *time) +{ + return EFI_SUCCESS; +} +#endif /* CONFIG_EFI_SECURE_BOOT */ + +static +efi_status_t EFIAPI efi_get_variable_common(u16 *variable_name, + const efi_guid_t *vendor, + u32 *attributes, + efi_uintn_t *data_size, void *data, + bool is_non_volatile) { char *native_name; efi_status_t ret; unsigned long in_size; - const char *val, *s; + const char *val = NULL, *s; + u64 time = 0; u32 attr; - EFI_ENTRY("\"%ls\" %pUl %p %p %p", variable_name, vendor, attributes, - data_size, data); - if (!variable_name || !vendor || !data_size) return EFI_EXIT(EFI_INVALID_PARAMETER); ret = efi_to_native(&native_name, variable_name, vendor); if (ret) - return EFI_EXIT(ret); + return ret; EFI_PRINT("get '%s'\n", native_name); val = env_get(native_name); free(native_name); if (!val) - return EFI_EXIT(EFI_NOT_FOUND); + return EFI_NOT_FOUND; - val = parse_attr(val, &attr); + val = parse_attr(val, &attr, &time); in_size = *data_size; @@ -198,7 +454,7 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, /* number of hexadecimal digits must be even */ if (len & 1) - return EFI_EXIT(EFI_DEVICE_ERROR); + return EFI_DEVICE_ERROR; /* two characters per byte: */ len /= 2; @@ -209,11 +465,13 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, goto out; } - if (!data) - return EFI_EXIT(EFI_INVALID_PARAMETER); + if (!data) { + debug("Variable with no data shouldn't exist.\n"); + return EFI_INVALID_PARAMETER; + } if (hex2bin(data, s, len)) - return EFI_EXIT(EFI_DEVICE_ERROR); + return EFI_DEVICE_ERROR; EFI_PRINT("got value: \"%s\"\n", s); } else if ((s = prefix(val, "(utf8)"))) { @@ -226,8 +484,10 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, goto out; } - if (!data) - return EFI_EXIT(EFI_INVALID_PARAMETER); + if (!data) { + debug("Variable with no data shouldn't exist.\n"); + return EFI_INVALID_PARAMETER; + } memcpy(data, s, len); ((char *)data)[len] = '\0'; @@ -235,13 +495,67 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, EFI_PRINT("got value: \"%s\"\n", (char *)data); } else { EFI_PRINT("invalid value: '%s'\n", val); - return EFI_EXIT(EFI_DEVICE_ERROR); + return EFI_DEVICE_ERROR; } out: if (attributes) *attributes = attr & EFI_VARIABLE_MASK; + return ret; +} + +static +efi_status_t EFIAPI efi_get_volatile_variable(u16 *variable_name, + const efi_guid_t *vendor, + u32 *attributes, + efi_uintn_t *data_size, + void *data) +{ + return efi_get_variable_common(variable_name, vendor, attributes, + data_size, data, false); +} + +efi_status_t EFIAPI efi_get_nonvolatile_variable(u16 *variable_name, + const efi_guid_t *vendor, + u32 *attributes, + efi_uintn_t *data_size, + void *data) +{ + return efi_get_variable_common(variable_name, vendor, attributes, + data_size, data, true); +} + +/** + * efi_efi_get_variable() - retrieve value of a UEFI variable + * + * This function implements the GetVariable runtime service. + * + * See the Unified Extensible Firmware Interface (UEFI) specification for + * details. + * + * @variable_name: name of the variable + * @vendor: vendor GUID + * @attributes: attributes of the variable + * @data_size: size of the buffer to which the variable value is copied + * @data: buffer to which the variable value is copied + * Return: status code + */ +efi_status_t EFIAPI efi_get_variable(u16 *variable_name, + const efi_guid_t *vendor, u32 *attributes, + efi_uintn_t *data_size, void *data) +{ + efi_status_t ret; + + EFI_ENTRY("\"%ls\" %pUl %p %p %p", variable_name, vendor, attributes, + data_size, data); + + ret = efi_get_volatile_variable(variable_name, vendor, attributes, + data_size, data); + if (ret == EFI_NOT_FOUND) + ret = efi_get_nonvolatile_variable(variable_name, vendor, + attributes, data_size, data); + return EFI_EXIT(ret); } @@ -275,6 +589,7 @@ static efi_status_t parse_uboot_variable(char *variable, char *guid, *name, *end, c; size_t name_len; efi_uintn_t old_variable_name_size; + u64 time; u16 *p; guid = strchr(variable, '_'); @@ -309,7 +624,7 @@ static efi_status_t parse_uboot_variable(char *variable, *(name - 1) = c; /* attributes */ - parse_attr(end, attributes); + parse_attr(end, attributes, &time); return EFI_SUCCESS; } @@ -391,7 +706,7 @@ efi_status_t EFIAPI efi_get_next_variable_name(efi_uintn_t *variable_name_size, list_len = hexport_r(&env_htab, '\n', H_MATCH_REGEX | H_MATCH_KEY, &efi_variables_list, 0, 1, regexlist); - /* 1 indicates that no match was found */ + if (list_len <= 1) return EFI_EXIT(EFI_NOT_FOUND); @@ -404,143 +719,286 @@ efi_status_t EFIAPI efi_get_next_variable_name(efi_uintn_t *variable_name_size, return EFI_EXIT(ret); } -/** - * efi_set_variable() - set value of a UEFI variable - * - * This function implements the SetVariable runtime service. - * - * See the Unified Extensible Firmware Interface (UEFI) specification for - * details. - * - * @variable_name: name of the variable - * @vendor: vendor GUID - * @attributes: attributes of the variable - * @data_size: size of the buffer with the variable value - * @data: buffer with the variable value - * Return: status code - */ -efi_status_t EFIAPI efi_set_variable(u16 *variable_name, - const efi_guid_t *vendor, u32 attributes, - efi_uintn_t data_size, const void *data) +static +efi_status_t EFIAPI efi_set_variable_common(u16 *variable_name, + const efi_guid_t *vendor, + u32 attributes, + efi_uintn_t data_size, + const void *data, + bool ro_check, + bool is_non_volatile) { - char *native_name = NULL, *val = NULL, *s; - const char *old_val; - size_t old_size; - efi_status_t ret = EFI_SUCCESS; + char *native_name = NULL, *old_data = NULL, *val = NULL, *s; + efi_uintn_t old_size; + bool append, delete; + u64 time = 0; u32 attr; + efi_status_t ret = EFI_SUCCESS; - EFI_ENTRY("\"%ls\" %pUl %x %zu %p", variable_name, vendor, attributes, - data_size, data); + debug("%s: set '%s'\n", __func__, native_name); if (!variable_name || !*variable_name || !vendor || ((attributes & EFI_VARIABLE_RUNTIME_ACCESS) && !(attributes & EFI_VARIABLE_BOOTSERVICE_ACCESS))) { ret = EFI_INVALID_PARAMETER; - goto out; + goto err; } ret = efi_to_native(&native_name, variable_name, vendor); if (ret) - goto out; + goto err; + + /* check if a variable exists */ + old_size = 0; + attr = 0; + ret = EFI_CALL(efi_get_variable(variable_name, vendor, &attr, + &old_size, NULL)); + if (ret == EFI_BUFFER_TOO_SMALL) { + if ((is_non_volatile && !(attr & EFI_VARIABLE_NON_VOLATILE)) || + (!is_non_volatile && (attr & EFI_VARIABLE_NON_VOLATILE))) { + ret = EFI_INVALID_PARAMETER; + goto err; + } + } - old_val = env_get(native_name); - if (old_val) { - old_val = parse_attr(old_val, &attr); + append = !!(attributes & EFI_VARIABLE_APPEND_WRITE); + attributes &= ~(u32)EFI_VARIABLE_APPEND_WRITE; + delete = !append && (!data_size || !attributes); - /* check read-only first */ - if (attr & READ_ONLY) { + /* check attributes */ + if (old_size) { + if (ro_check && (attr & READ_ONLY)) { ret = EFI_WRITE_PROTECTED; - goto out; - } - - if ((data_size == 0 && - !(attributes & EFI_VARIABLE_APPEND_WRITE)) || - !attributes) { - /* delete the variable: */ - env_set(native_name, NULL); - ret = EFI_SUCCESS; - goto out; + goto err; } /* attributes won't be changed */ - if (attr != (attributes & ~EFI_VARIABLE_APPEND_WRITE)) { + if (!delete && + ((ro_check && attr != attributes) || + (!ro_check && ((attr & ~(u32)READ_ONLY) + != (attributes & ~(u32)READ_ONLY))))) { ret = EFI_INVALID_PARAMETER; - goto out; - } - - if (attributes & EFI_VARIABLE_APPEND_WRITE) { - if (!prefix(old_val, "(blob)")) { - ret = EFI_DEVICE_ERROR; - goto out; - } - old_size = strlen(old_val); - } else { - old_size = 0; + goto err; } } else { - if (data_size == 0 || !attributes || - (attributes & EFI_VARIABLE_APPEND_WRITE)) { + if (delete || append) { /* * Trying to delete or to update a non-existent * variable. */ ret = EFI_NOT_FOUND; - goto out; + goto err; + } + } + + if (((!u16_strcmp(variable_name, L"PK") || + !u16_strcmp(variable_name, L"KEK")) && + !guidcmp(vendor, &efi_global_variable_guid)) || + ((!u16_strcmp(variable_name, L"db") || + !u16_strcmp(variable_name, L"dbx")) && + !guidcmp(vendor, &efi_guid_image_security_database))) { + /* authentication is mandatory */ + if (!(attributes & + EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)) { + debug("%ls: AUTHENTICATED_WRITE_ACCESS required\n", + variable_name); + ret = EFI_INVALID_PARAMETER; + goto err; } + } + + /* authenticate a variable */ + if (IS_ENABLED(CONFIG_EFI_SECURE_BOOT)) { + if (attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS) { + ret = EFI_INVALID_PARAMETER; + goto err; + } + if (attributes & + EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) { + ret = efi_variable_authenticate(variable_name, vendor, + &data_size, &data, + attributes, &attr, + &time); + if (ret != EFI_SUCCESS) + goto err; + + /* last chance to check for delete */ + if (!data_size) + delete = true; + } + } else { + if (attributes & + (EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS | + EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)) { + debug("Secure boot is not configured\n"); + ret = EFI_INVALID_PARAMETER; + goto err; + } + } + + /* delete a variable */ + if (delete) { + /* !old_size case has been handled before */ + val = NULL; + ret = EFI_SUCCESS; + goto out; + } + if (append) { + old_data = malloc(old_size); + if (!old_data) { + return EFI_OUT_OF_RESOURCES; + goto err; + } + ret = EFI_CALL(efi_get_variable(variable_name, vendor, + &attr, &old_size, old_data)); + if (ret != EFI_SUCCESS) + goto err; + } else { old_size = 0; } - val = malloc(old_size + 2 * data_size - + strlen("{ro,run,boot,nv}(blob)") + 1); + val = malloc(2 * old_size + 2 * data_size + + strlen("{ro,run,boot,nv,time=0123456701234567}(blob)") + + 1); if (!val) { ret = EFI_OUT_OF_RESOURCES; - goto out; + goto err; } s = val; - /* store attributes */ - attributes &= (EFI_VARIABLE_NON_VOLATILE | + /* + * store attributes + */ + attributes &= (READ_ONLY | + EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | - EFI_VARIABLE_RUNTIME_ACCESS); + EFI_VARIABLE_RUNTIME_ACCESS | + EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS); s += sprintf(s, "{"); while (attributes) { - u32 attr = 1 << (ffs(attributes) - 1); + attr = 1 << (ffs(attributes) - 1); - if (attr == EFI_VARIABLE_NON_VOLATILE) + if (attr == READ_ONLY) { + s += sprintf(s, "ro"); + } else if (attr == EFI_VARIABLE_NON_VOLATILE) { s += sprintf(s, "nv"); - else if (attr == EFI_VARIABLE_BOOTSERVICE_ACCESS) + } else if (attr == EFI_VARIABLE_BOOTSERVICE_ACCESS) { s += sprintf(s, "boot"); - else if (attr == EFI_VARIABLE_RUNTIME_ACCESS) + } else if (attr == EFI_VARIABLE_RUNTIME_ACCESS) { s += sprintf(s, "run"); + } else if (attr == + EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS) { + s += sprintf(s, "time="); + s = bin2hex(s, (u8 *)&time, sizeof(time)); + } attributes &= ~attr; if (attributes) s += sprintf(s, ","); } s += sprintf(s, "}"); - - if (old_size) - /* APPEND_WRITE */ - s += sprintf(s, old_val); - else - s += sprintf(s, "(blob)"); + s += sprintf(s, "(blob)"); /* store payload: */ + if (append) + s = bin2hex(s, old_data, old_size); s = bin2hex(s, data, data_size); *s = '\0'; EFI_PRINT("setting: %s=%s\n", native_name, val); +out: if (env_set(native_name, val)) ret = EFI_DEVICE_ERROR; + else + ret = EFI_SUCCESS; -out: +err: free(native_name); + free(old_data); free(val); - return EFI_EXIT(ret); + return ret; +} + +static +efi_status_t EFIAPI efi_set_volatile_variable(u16 *variable_name, + const efi_guid_t *vendor, + u32 attributes, + efi_uintn_t data_size, + const void *data, + bool ro_check) +{ + return efi_set_variable_common(variable_name, vendor, attributes, + data_size, data, ro_check, false); +} + +efi_status_t EFIAPI efi_set_nonvolatile_variable(u16 *variable_name, + const efi_guid_t *vendor, + u32 attributes, + efi_uintn_t data_size, + const void *data, + bool ro_check) +{ + efi_status_t ret; + + ret = efi_set_variable_common(variable_name, vendor, attributes, + data_size, data, ro_check, true); + + return ret; +} + +static efi_status_t efi_set_variable_internal(u16 *variable_name, + const efi_guid_t *vendor, + u32 attributes, + efi_uintn_t data_size, + const void *data, + bool ro_check) +{ + efi_status_t ret; + + if (attributes & EFI_VARIABLE_NON_VOLATILE) + ret = efi_set_nonvolatile_variable(variable_name, vendor, + attributes, + data_size, data, ro_check); + else + ret = efi_set_volatile_variable(variable_name, vendor, + attributes, data_size, data, + ro_check); + + return ret; +} + +/** + * efi_set_variable() - set value of a UEFI variable + * + * This function implements the SetVariable runtime service. + * + * See the Unified Extensible Firmware Interface (UEFI) specification for + * details. + * + * @variable_name: name of the variable + * @vendor: vendor GUID + * @attributes: attributes of the variable + * @data_size: size of the buffer with the variable value + * @data: buffer with the variable value + * Return: status code + */ +efi_status_t EFIAPI efi_set_variable(u16 *variable_name, + const efi_guid_t *vendor, u32 attributes, + efi_uintn_t data_size, const void *data) +{ + EFI_ENTRY("\"%ls\" %pUl %x %zu %p", variable_name, vendor, attributes, + data_size, data); + + /* READ_ONLY bit is not part of API */ + attributes &= ~(u32)READ_ONLY; + + return EFI_EXIT(efi_set_variable_internal(variable_name, vendor, + attributes, data_size, data, + true)); } /** |