diff options
Diffstat (limited to 'util/smmstoretool/vs.c')
| -rw-r--r-- | util/smmstoretool/vs.c | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/util/smmstoretool/vs.c b/util/smmstoretool/vs.c new file mode 100644 index 0000000000..a1167ca2de --- /dev/null +++ b/util/smmstoretool/vs.c @@ -0,0 +1,232 @@ +/* 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); + } +} |