X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=lib%2Fefi_loader%2Fefi_variable.c;h=fe2f26459136befd6190879b5b6416aa91610375;hb=0aadc0786e4a249cddd37efd8875f09e645be4cd;hp=2ac27731fe57fe440246cdd8da10c6c28ac8e32f;hpb=8377ee36d6a6cfdad56649e2cec64cfb97e3ae68;p=oweals%2Fu-boot.git diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c index 2ac27731fe..fe2f264591 100644 --- a/lib/efi_loader/efi_variable.c +++ b/lib/efi_loader/efi_variable.c @@ -1,14 +1,17 @@ // SPDX-License-Identifier: GPL-2.0+ /* - * EFI utils + * UEFI runtime variable services * - * Copyright (c) 2017 Rob Clark + * Copyright (c) 2017 Rob Clark */ -#include -#include +#include #include +#include #include +#include +#include +#include #define READ_ONLY BIT(31) @@ -47,6 +50,19 @@ #define PREFIX_LEN (strlen("efi_xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx_")) +/** + * efi_to_native() - convert the UEFI variable name and vendor GUID to U-Boot + * variable name + * + * The U-Boot variable name is a concatenation of prefix 'efi', the hexstring + * encoded vendor GUID, and the UTF-8 encoded UEFI variable name separated by + * underscores, e.g. 'efi_8be4df61-93ca-11d2-aa0d-00e098032b8c_BootOrder'. + * + * @native: pointer to pointer to U-Boot variable name + * @variable_name: UEFI variable name + * @vendor: vendor GUID + * Return: status code + */ static efi_status_t efi_to_native(char **native, const u16 *variable_name, const efi_guid_t *vendor) { @@ -65,6 +81,15 @@ static efi_status_t efi_to_native(char **native, const u16 *variable_name, return EFI_SUCCESS; } +/** + * prefix() - skip over prefix + * + * Skip over a prefix string. + * + * @str: string with prefix + * @prefix: prefix string + * Return: string without prefix, or NULL if prefix not found + */ static const char *prefix(const char *str, const char *prefix) { size_t n = strlen(prefix); @@ -73,7 +98,16 @@ static const char *prefix(const char *str, const char *prefix) return NULL; } -/* parse attributes part of variable value, if present: */ +/** + * parse_attr() - decode attributes part of variable value + * + * Convert the string encoded attributes of a UEFI variable to a bit mask. + * TODO: Several attributes are not supported. + * + * @str: value of U-Boot variable + * @attrp: pointer to UEFI attributes + * Return: pointer to remainder of U-Boot variable value + */ static const char *parse_attr(const char *str, u32 *attrp) { u32 attr = 0; @@ -91,6 +125,8 @@ static const char *parse_attr(const char *str, u32 *attrp) if ((s = prefix(str, "ro"))) { attr |= READ_ONLY; + } else if ((s = prefix(str, "nv"))) { + attr |= EFI_VARIABLE_NON_VOLATILE; } else if ((s = prefix(str, "boot"))) { attr |= EFI_VARIABLE_BOOTSERVICE_ACCESS; } else if ((s = prefix(str, "run"))) { @@ -111,7 +147,21 @@ static const char *parse_attr(const char *str, u32 *attrp) return str; } -/* http://wiki.phoenix.com/wiki/index.php/EFI_RUNTIME_SERVICES#GetVariable.28.29 */ +/** + * 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) @@ -132,7 +182,7 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, if (ret) return EFI_EXIT(ret); - debug("%s: get '%s'\n", __func__, native_name); + EFI_PRINT("get '%s'\n", native_name); val = env_get(native_name); free(native_name); @@ -154,8 +204,10 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, len /= 2; *data_size = len; - if (in_size < len) - return EFI_EXIT(EFI_BUFFER_TOO_SMALL); + if (in_size < len) { + ret = EFI_BUFFER_TOO_SMALL; + goto out; + } if (!data) return EFI_EXIT(EFI_INVALID_PARAMETER); @@ -163,14 +215,16 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, if (hex2bin(data, s, len)) return EFI_EXIT(EFI_DEVICE_ERROR); - debug("%s: got value: \"%s\"\n", __func__, s); + EFI_PRINT("got value: \"%s\"\n", s); } else if ((s = prefix(val, "(utf8)"))) { unsigned len = strlen(s) + 1; *data_size = len; - if (in_size < len) - return EFI_EXIT(EFI_BUFFER_TOO_SMALL); + if (in_size < len) { + ret = EFI_BUFFER_TOO_SMALL; + goto out; + } if (!data) return EFI_EXIT(EFI_INVALID_PARAMETER); @@ -178,41 +232,209 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name, memcpy(data, s, len); ((char *)data)[len] = '\0'; - debug("%s: got value: \"%s\"\n", __func__, (char *)data); + EFI_PRINT("got value: \"%s\"\n", (char *)data); } else { - debug("%s: invalid value: '%s'\n", __func__, val); + EFI_PRINT("invalid value: '%s'\n", val); return EFI_EXIT(EFI_DEVICE_ERROR); } +out: if (attributes) *attributes = attr & EFI_VARIABLE_MASK; - return EFI_EXIT(EFI_SUCCESS); + return EFI_EXIT(ret); } -/* http://wiki.phoenix.com/wiki/index.php/EFI_RUNTIME_SERVICES#GetNextVariableName.28.29 */ +static char *efi_variables_list; +static char *efi_cur_variable; + +/** + * parse_uboot_variable() - parse a u-boot variable and get uefi-related + * information + * @variable: whole data of u-boot variable (ie. name=value) + * @variable_name_size: size of variable_name buffer in byte + * @variable_name: name of uefi variable in u16, null-terminated + * @vendor: vendor's guid + * @attributes: attributes + * + * A uefi variable is encoded into a u-boot variable as described above. + * This function parses such a u-boot variable and retrieve uefi-related + * information into respective parameters. In return, variable_name_size + * is the size of variable name including NULL. + * + * Return: EFI_SUCCESS if parsing is OK, EFI_NOT_FOUND when + * the entire variable list has been returned, + * otherwise non-zero status code + */ +static efi_status_t parse_uboot_variable(char *variable, + efi_uintn_t *variable_name_size, + u16 *variable_name, + const efi_guid_t *vendor, + u32 *attributes) +{ + char *guid, *name, *end, c; + size_t name_len; + efi_uintn_t old_variable_name_size; + u16 *p; + + guid = strchr(variable, '_'); + if (!guid) + return EFI_INVALID_PARAMETER; + guid++; + name = strchr(guid, '_'); + if (!name) + return EFI_INVALID_PARAMETER; + name++; + end = strchr(name, '='); + if (!end) + return EFI_INVALID_PARAMETER; + + name_len = end - name; + old_variable_name_size = *variable_name_size; + *variable_name_size = sizeof(u16) * (name_len + 1); + if (old_variable_name_size < *variable_name_size) + return EFI_BUFFER_TOO_SMALL; + + end++; /* point to value */ + + /* variable name */ + p = variable_name; + utf8_utf16_strncpy(&p, name, name_len); + variable_name[name_len] = 0; + + /* guid */ + c = *(name - 1); + *(name - 1) = '\0'; /* guid need be null-terminated here */ + uuid_str_to_bin(guid, (unsigned char *)vendor, UUID_STR_FORMAT_GUID); + *(name - 1) = c; + + /* attributes */ + parse_attr(end, attributes); + + return EFI_SUCCESS; +} + +/** + * efi_get_next_variable_name() - enumerate the current variable names + * + * @variable_name_size: size of variable_name buffer in byte + * @variable_name: name of uefi variable's name in u16 + * @vendor: vendor's guid + * + * This function implements the GetNextVariableName service. + * + * See the Unified Extensible Firmware Interface (UEFI) specification for + * details. + * + * Return: status code + */ efi_status_t EFIAPI efi_get_next_variable_name(efi_uintn_t *variable_name_size, u16 *variable_name, - const efi_guid_t *vendor) + efi_guid_t *vendor) { + char *native_name, *variable; + ssize_t name_len, list_len; + char regex[256]; + char * const regexlist[] = {regex}; + u32 attributes; + int i; + efi_status_t ret; + EFI_ENTRY("%p \"%ls\" %pUl", variable_name_size, variable_name, vendor); - return EFI_EXIT(EFI_DEVICE_ERROR); + if (!variable_name_size || !variable_name || !vendor) + return EFI_EXIT(EFI_INVALID_PARAMETER); + + if (variable_name[0]) { + /* check null-terminated string */ + for (i = 0; i < *variable_name_size; i++) + if (!variable_name[i]) + break; + if (i >= *variable_name_size) + return EFI_EXIT(EFI_INVALID_PARAMETER); + + /* search for the last-returned variable */ + ret = efi_to_native(&native_name, variable_name, vendor); + if (ret) + return EFI_EXIT(ret); + + name_len = strlen(native_name); + for (variable = efi_variables_list; variable && *variable;) { + if (!strncmp(variable, native_name, name_len) && + variable[name_len] == '=') + break; + + variable = strchr(variable, '\n'); + if (variable) + variable++; + } + + free(native_name); + if (!(variable && *variable)) + return EFI_EXIT(EFI_INVALID_PARAMETER); + + /* next variable */ + variable = strchr(variable, '\n'); + if (variable) + variable++; + if (!(variable && *variable)) + return EFI_EXIT(EFI_NOT_FOUND); + } else { + /* + *new search: free a list used in the previous search + */ + free(efi_variables_list); + efi_variables_list = NULL; + efi_cur_variable = NULL; + + snprintf(regex, 256, "efi_.*-.*-.*-.*-.*_.*"); + 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); + + variable = efi_variables_list; + } + + ret = parse_uboot_variable(variable, variable_name_size, variable_name, + vendor, &attributes); + + return EFI_EXIT(ret); } -/* http://wiki.phoenix.com/wiki/index.php/EFI_RUNTIME_SERVICES#SetVariable.28.29 */ +/** + * 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) { char *native_name = NULL, *val = NULL, *s; + const char *old_val; + size_t old_size; efi_status_t ret = EFI_SUCCESS; u32 attr; EFI_ENTRY("\"%ls\" %pUl %x %zu %p", variable_name, vendor, attributes, data_size, data); - if (!variable_name || !vendor) { + if (!variable_name || !*variable_name || !vendor || + ((attributes & EFI_VARIABLE_RUNTIME_ACCESS) && + !(attributes & EFI_VARIABLE_BOOTSERVICE_ACCESS))) { ret = EFI_INVALID_PARAMETER; goto out; } @@ -221,28 +443,56 @@ efi_status_t EFIAPI efi_set_variable(u16 *variable_name, if (ret) goto out; -#define ACCESS_ATTR (EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_BOOTSERVICE_ACCESS) - - if ((data_size == 0) || !(attributes & ACCESS_ATTR)) { - /* delete the variable: */ - env_set(native_name, NULL); - ret = EFI_SUCCESS; - goto out; - } - - val = env_get(native_name); - if (val) { - parse_attr(val, &attr); + old_val = env_get(native_name); + if (old_val) { + old_val = parse_attr(old_val, &attr); + /* check read-only first */ if (attr & READ_ONLY) { - /* We should not free val */ - val = NULL; 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; + } + + /* attributes won't be changed */ + if (attr != (attributes & ~EFI_VARIABLE_APPEND_WRITE)) { + 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; + } + } else { + if (data_size == 0 || !attributes || + (attributes & EFI_VARIABLE_APPEND_WRITE)) { + /* + * Trying to delete or to update a non-existent + * variable. + */ + ret = EFI_NOT_FOUND; + goto out; + } + + old_size = 0; } - val = malloc(2 * data_size + strlen("{ro,run,boot}(blob)") + 1); + val = malloc(old_size + 2 * data_size + + strlen("{ro,run,boot,nv}(blob)") + 1); if (!val) { ret = EFI_OUT_OF_RESOURCES; goto out; @@ -250,13 +500,17 @@ efi_status_t EFIAPI efi_set_variable(u16 *variable_name, s = val; - /* store attributes: */ - attributes &= (EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS); + /* store attributes */ + attributes &= (EFI_VARIABLE_NON_VOLATILE | + EFI_VARIABLE_BOOTSERVICE_ACCESS | + EFI_VARIABLE_RUNTIME_ACCESS); s += sprintf(s, "{"); while (attributes) { u32 attr = 1 << (ffs(attributes) - 1); - if (attr == EFI_VARIABLE_BOOTSERVICE_ACCESS) + if (attr == EFI_VARIABLE_NON_VOLATILE) + s += sprintf(s, "nv"); + else if (attr == EFI_VARIABLE_BOOTSERVICE_ACCESS) s += sprintf(s, "boot"); else if (attr == EFI_VARIABLE_RUNTIME_ACCESS) s += sprintf(s, "run"); @@ -267,12 +521,17 @@ efi_status_t EFIAPI efi_set_variable(u16 *variable_name, } s += sprintf(s, "}"); + if (old_size) + /* APPEND_WRITE */ + s += sprintf(s, old_val); + else + s += sprintf(s, "(blob)"); + /* store payload: */ - s += sprintf(s, "(blob)"); s = bin2hex(s, data, data_size); *s = '\0'; - debug("%s: setting: %s=%s\n", __func__, native_name, val); + EFI_PRINT("setting: %s=%s\n", native_name, val); if (env_set(native_name, val)) ret = EFI_DEVICE_ERROR; @@ -283,3 +542,103 @@ out: return EFI_EXIT(ret); } + +/** + * efi_query_variable_info() - get information about EFI variables + * + * This function implements the QueryVariableInfo() runtime service. + * + * See the Unified Extensible Firmware Interface (UEFI) specification for + * details. + * + * @attributes: bitmask to select variables to be + * queried + * @maximum_variable_storage_size: maximum size of storage area for the + * selected variable types + * @remaining_variable_storage_size: remaining size of storage are for the + * selected variable types + * @maximum_variable_size: maximum size of a variable of the + * selected type + * Returns: status code + */ +efi_status_t __efi_runtime EFIAPI efi_query_variable_info( + u32 attributes, + u64 *maximum_variable_storage_size, + u64 *remaining_variable_storage_size, + u64 *maximum_variable_size) +{ + return EFI_UNSUPPORTED; +} + +/** + * efi_get_variable_runtime() - runtime implementation of GetVariable() + * + * @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 + */ +static efi_status_t __efi_runtime EFIAPI +efi_get_variable_runtime(u16 *variable_name, const efi_guid_t *vendor, + u32 *attributes, efi_uintn_t *data_size, void *data) +{ + return EFI_UNSUPPORTED; +} + +/** + * efi_get_next_variable_name_runtime() - runtime implementation of + * GetNextVariable() + * + * @variable_name_size: size of variable_name buffer in byte + * @variable_name: name of uefi variable's name in u16 + * @vendor: vendor's guid + * Return: status code + */ +static efi_status_t __efi_runtime EFIAPI +efi_get_next_variable_name_runtime(efi_uintn_t *variable_name_size, + u16 *variable_name, efi_guid_t *vendor) +{ + return EFI_UNSUPPORTED; +} + +/** + * efi_set_variable_runtime() - runtime implementation of SetVariable() + * + * @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 + */ +static efi_status_t __efi_runtime EFIAPI +efi_set_variable_runtime(u16 *variable_name, const efi_guid_t *vendor, + u32 attributes, efi_uintn_t data_size, + const void *data) +{ + return EFI_UNSUPPORTED; +} + +/** + * efi_variables_boot_exit_notify() - notify ExitBootServices() is called + */ +void efi_variables_boot_exit_notify(void) +{ + efi_runtime_services.get_variable = efi_get_variable_runtime; + efi_runtime_services.get_next_variable_name = + efi_get_next_variable_name_runtime; + efi_runtime_services.set_variable = efi_set_variable_runtime; + efi_update_table_header_crc32(&efi_runtime_services.hdr); +} + +/** + * efi_init_variables() - initialize variable services + * + * Return: status code + */ +efi_status_t efi_init_variables(void) +{ + return EFI_SUCCESS; +}