efi_loader: implement GetNextVariableName()

The current GetNextVariableName() is a placeholder.
With this patch, it works well as expected.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
rebased on efi-next
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c
index cfb3168e779190fbbbc0e66bf53397e7011385eb..d94a5f69748dca4cb51a1f5a9d7ad90c52bef71f 100644 (file)
--- a/lib/efi_loader/efi_variable.c
+++ b/lib/efi_loader/efi_variable.c
@@ -9,6 +9,9 @@
 #include <charset.h>
 #include <efi_loader.h>
 #include <hexdump.h>
+#include <environment.h>
+#include <search.h>
+#include <uuid.h>
 
 #define READ_ONLY BIT(31)
 
@@ -235,28 +238,161 @@ efi_status_t EFIAPI efi_get_variable(u16 *variable_name,
        return EFI_EXIT(EFI_SUCCESS);
 }
 
+static char *efi_variables_list;
+static char *efi_cur_variable;
+
 /**
- * efi_efi_get_next_variable() - get next UEFI 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
  *
- * This function implements the GetNextVariable runtime service.
+ * 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.
+ * details: http://wiki.phoenix.com/wiki/index.php/
+ *             EFI_RUNTIME_SERVICES#GetNextVariableName.28.29
  *
- * @variable_name_size:        on entry size of the buffer for the variable name, on
- *                     exit the length of the name of the next variable
- * @variable_name:     on entry name of the current variable, on exit the name
- *                     of the next variable
- * @vendor:            vendor GUID
- * Return:             status code
+ * 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)
 {
+       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)
+               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);
+               if (list_len <= 0)
+                       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);
 }
 
 /**