$NetBSD: patch-lib_efi__loader_efi__variable.c,v 1.1 2019/04/12 07:08:15 skrll Exp $ --- lib/efi_loader/efi_variable.c.orig 2019-04-06 16:01:44.521947778 +0000 +++ lib/efi_loader/efi_variable.c @@ -8,6 +8,10 @@ #include #include #include +#include +#include +#include +#include #define READ_ONLY BIT(31) @@ -98,6 +102,19 @@ static char *mem2hex(char *hexstr, const return hexstr; } +/** + * 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, efi_guid_t *vendor) { @@ -116,6 +133,15 @@ static efi_status_t efi_to_native(char * 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); @@ -124,7 +150,16 @@ static const char *prefix(const char *st 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; @@ -162,7 +197,21 @@ static const char *parse_attr(const char return str; } -/* http://wiki.phoenix.com/wiki/index.php/EFI_RUNTIME_SERVICES#GetVariable.28.29 */ +/** + * 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, efi_guid_t *vendor, u32 *attributes, efi_uintn_t *data_size, void *data) @@ -241,17 +290,179 @@ efi_status_t EFIAPI efi_get_variable(u16 return EFI_EXIT(EFI_SUCCESS); } -/* 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; + unsigned long name_len; + 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; + if (*variable_name_size < (name_len + 1)) { + *variable_name_size = name_len + 1; + 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; + *variable_name_size = name_len + 1; + + /* 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: http://wiki.phoenix.com/wiki/index.php/ + * EFI_RUNTIME_SERVICES#GetNextVariableName.28.29 + * + * Return: status code + */ efi_status_t EFIAPI efi_get_next_variable_name(efi_uintn_t *variable_name_size, - u16 *variable_name, - efi_guid_t *vendor) + u16 *variable_name, + 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_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, efi_guid_t *vendor, u32 attributes, efi_uintn_t data_size, void *data)