| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| |
| #include "vs.h" |
| |
| #include <limits.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "udk2017.h" |
| #include "utils.h" |
| |
| static size_t get_var_hdr_size(bool auth_vars) |
| { |
| if (auth_vars) |
| return sizeof(AUTHENTICATED_VARIABLE_HEADER); |
| return sizeof(VARIABLE_HEADER); |
| } |
| |
| struct var_store_t vs_load(struct mem_range_t vs_data, bool auth_vars) |
| { |
| uint8_t *var_hdr = vs_data.start; |
| |
| struct var_store_t vs = { |
| .auth_vars = auth_vars, |
| .vars = NULL, |
| }; |
| |
| struct var_t *last_var = NULL; |
| |
| const size_t var_hdr_size = get_var_hdr_size(auth_vars); |
| while (var_hdr + var_hdr_size < vs_data.start + vs_data.length) { |
| uint16_t start_id; |
| uint8_t state; |
| struct var_t var = {0}; |
| uint8_t *var_data = var_hdr; |
| |
| if (auth_vars) { |
| const AUTHENTICATED_VARIABLE_HEADER *auth_hdr = |
| (void *)var_data; |
| |
| start_id = auth_hdr->StartId; |
| state = auth_hdr->State; |
| |
| var.reserved = auth_hdr->Reserved; |
| var.attrs = auth_hdr->Attributes; |
| var.name_size = auth_hdr->NameSize; |
| var.data_size = auth_hdr->DataSize; |
| var.guid = auth_hdr->VendorGuid; |
| } else { |
| const VARIABLE_HEADER *no_auth_hdr = (void *)var_data; |
| |
| start_id = no_auth_hdr->StartId; |
| state = no_auth_hdr->State; |
| |
| var.reserved = no_auth_hdr->Reserved; |
| var.attrs = no_auth_hdr->Attributes; |
| var.name_size = no_auth_hdr->NameSize; |
| var.data_size = no_auth_hdr->DataSize; |
| var.guid = no_auth_hdr->VendorGuid; |
| } |
| |
| var_hdr += HEADER_ALIGN(var_hdr_size + |
| var.name_size + |
| var.data_size); |
| |
| if (start_id != VARIABLE_DATA) |
| break; |
| |
| if (state != VAR_ADDED) |
| continue; |
| |
| if (var.data_size == UINT32_MAX || |
| var.name_size == UINT32_MAX || |
| var.attrs == UINT32_MAX) |
| continue; |
| |
| CHAR16 *name = (void *)(var_data + var_hdr_size); |
| var.name = xmalloc(var.name_size); |
| memcpy(var.name, name, var.name_size); |
| |
| uint8_t *data = |
| (void *)(var_data + var_hdr_size + var.name_size); |
| var.data = xmalloc(var.data_size); |
| memcpy(var.data, data, var.data_size); |
| |
| struct var_t *var_node = xmalloc(sizeof(*var_node)); |
| *var_node = var; |
| if (last_var != NULL) |
| last_var->next = var_node; |
| else if (vs.vars == NULL) |
| vs.vars = var_node; |
| last_var = var_node; |
| } |
| |
| return vs; |
| } |
| |
| static void store_var(const struct var_t *var, bool auth_vars, uint8_t *data) |
| { |
| if (auth_vars) { |
| AUTHENTICATED_VARIABLE_HEADER hdr; |
| memset(&hdr, 0xff, sizeof(hdr)); |
| |
| hdr.StartId = VARIABLE_DATA; |
| hdr.State = VAR_ADDED; |
| hdr.Reserved = var->reserved; |
| hdr.Attributes = var->attrs; |
| hdr.VendorGuid = var->guid; |
| hdr.NameSize = var->name_size; |
| hdr.DataSize = var->data_size; |
| |
| memcpy(data, &hdr, sizeof(hdr)); |
| data += sizeof(hdr); |
| } else { |
| VARIABLE_HEADER hdr; |
| memset(&hdr, 0xff, sizeof(hdr)); |
| |
| hdr.StartId = VARIABLE_DATA; |
| hdr.State = VAR_ADDED; |
| hdr.Reserved = var->reserved; |
| hdr.Attributes = var->attrs; |
| hdr.VendorGuid = var->guid; |
| hdr.NameSize = var->name_size; |
| hdr.DataSize = var->data_size; |
| |
| memcpy(data, &hdr, sizeof(hdr)); |
| data += sizeof(hdr); |
| } |
| |
| memcpy(data, var->name, var->name_size); |
| memcpy(data + var->name_size, var->data, var->data_size); |
| } |
| |
| bool vs_store(struct var_store_t *vs, struct mem_range_t vs_data) |
| { |
| uint8_t *out_data = vs_data.start; |
| |
| const size_t var_hdr_size = get_var_hdr_size(vs->auth_vars); |
| for (struct var_t *var = vs->vars; var != NULL; var = var->next) { |
| const size_t var_size = |
| var_hdr_size + var->name_size + var->data_size; |
| if (out_data + var_size > vs_data.start + vs_data.length) { |
| fprintf(stderr, |
| "Not enough space to serialize Variable Store.\n"); |
| return false; |
| } |
| |
| store_var(var, vs->auth_vars, out_data); |
| out_data += HEADER_ALIGN(var_size); |
| } |
| |
| // The rest is "uninitialized". |
| memset(out_data, 0xff, vs_data.length - (out_data - vs_data.start)); |
| |
| return true; |
| } |
| |
| struct var_t *vs_new_var(struct var_store_t *vs) |
| { |
| struct var_t *new_var = xmalloc(sizeof(*new_var)); |
| |
| memset(new_var, 0, sizeof(*new_var)); |
| new_var->attrs = EFI_VARIABLE_NON_VOLATILE |
| | EFI_VARIABLE_BOOTSERVICE_ACCESS |
| | EFI_VARIABLE_RUNTIME_ACCESS; |
| |
| struct var_t *var = vs->vars; |
| if (var == NULL) { |
| vs->vars = new_var; |
| } else { |
| while (var->next != NULL) |
| var = var->next; |
| var->next = new_var; |
| } |
| |
| return new_var; |
| } |
| |
| struct var_t *vs_find(struct var_store_t *vs, |
| const char name[], |
| const EFI_GUID *guid) |
| { |
| size_t name_size; |
| CHAR16 *uchar_name = to_uchars(name, &name_size); |
| |
| struct var_t *var; |
| for (var = vs->vars; var != NULL; var = var->next) { |
| if (var->name_size != name_size) |
| continue; |
| if (memcmp(var->name, uchar_name, name_size) != 0) |
| continue; |
| if (memcmp(&var->guid, guid, sizeof(*guid)) != 0) |
| continue; |
| break; |
| } |
| |
| free(uchar_name); |
| return var; |
| } |
| |
| static void free_var(struct var_t *var) |
| { |
| free(var->name); |
| free(var->data); |
| free(var); |
| } |
| |
| void vs_delete(struct var_store_t *vs, struct var_t *var) |
| { |
| if (vs->vars == var) { |
| vs->vars = var->next; |
| free_var(var); |
| return; |
| } |
| |
| for (struct var_t *v = vs->vars; v != NULL; v = v->next) { |
| if (v->next == var) { |
| v->next = var->next; |
| free_var(var); |
| return; |
| } |
| } |
| } |
| |
| void vs_free(struct var_store_t *vs) |
| { |
| for (struct var_t *next, *var = vs->vars; var != NULL; var = next) { |
| next = var->next; |
| free_var(var); |
| } |
| } |