diff options
Diffstat (limited to 'tboot/eficonfig.c')
| -rw-r--r-- | tboot/eficonfig.c | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/tboot/eficonfig.c b/tboot/eficonfig.c new file mode 100644 index 0000000..2d6d699 --- /dev/null +++ b/tboot/eficonfig.c @@ -0,0 +1,299 @@ +/* + * eficonfig.c: EFI related configuration settings and data. + * + * Copyright (c) 2017 Assured Information Security. + * + * Ross Philipson <philipsonr@ainfosec.com> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * * Neither the name of the Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <config.h> +#include <efibase.h> +#include <stdbool.h> +#include <types.h> +#include <ctype.h> +#include <string.h> +#include <misc.h> +#include <eficore.h> +#include <eficonfig.h> +#include <printk.h> + +/* The main config files read from disk */ +efi_file_t g_efi_configs[EFI_CONFIG_MAX]; + +/* Root path to TBOOT image home */ +wchar_t g_tboot_dir[EFI_MAX_PATH]; + +/* Is this pre or post EBS */ +bool g_post_ebs = false; + +const char *g_kernel_cmdline = ""; + +/* Core TXT and TBOOT files stored in EfiRuntimeServicesData */ +efi_file_t g_platform_sinit; +efi_file_t g_platform_racm; +efi_file_t g_lcp; + +/* The xen image plush the kernl and ramdisk images passed back from Xen */ +efi_file_t g_xen; +efi_file_t g_kernel; +efi_file_t g_ramdisk; + +/* EFI memory map just before EBS from Xen */ +void *g_memory_map; +uint64_t g_memory_map_size; +uint64_t g_memory_desc_size; + +/* Xen post launch callback */ +uint64_t g_xen_post_launch_cb; + +void efi_cfg_init(void) +{ + memset(&g_tboot_dir[0], 0, EFI_MAX_PATH*sizeof(wchar_t)); + memset(&g_efi_configs[0], 0, EFI_CONFIG_MAX*sizeof(efi_file_t)); +} + +efi_file_t *efi_get_configs(void) +{ + return &g_efi_configs[0]; +} + +void efi_cfg_pre_parse(efi_file_t *config) +{ + char *ptr = config->u.buffer, *end = ptr + config->size; + bool start = true, comment = false; + + for ( ; ptr < end; ++ptr ) { + if ( iscntrl(*ptr) ) { + comment = false; + start = true; + *ptr = 0; + } + else if ( comment || (start && isspace(*ptr)) ) { + *ptr = 0; + } + else if ( *ptr == '#' || (start && *ptr == ';') ) { + comment = true; + *ptr = 0; + } + else + start = false; + } + if ( config->size && end[-1] ) + printk("No newline at end of config file last line will be ignored.\n"); +} + +char *efi_cfg_get_value(int index, const char *section, + const char *item) +{ + efi_file_t *config; + char *ptr, *end; + size_t slen = section ? strlen(section) : 0, ilen = strlen(item); + bool match = !slen; + + if (index >= EFI_CONFIG_MAX) + return NULL; + + config = &g_efi_configs[index]; + ptr = config->u.buffer; + end = ptr + config->size; + + for ( ; ptr < end; ++ptr ) { + switch ( *ptr ) { + case 0: + continue; + case '[': + if ( !slen ) + break; + if ( match ) + return NULL; + match = strncmp(++ptr, section, slen) == 0 && ptr[slen] == ']'; + break; + default: + if ( match && strncmp(ptr, item, ilen) == 0 && ptr[ilen] == '=' ) { + ptr += ilen + 1; + /* strip off any leading spaces */ + while ( *ptr && isspace(*ptr) ) + ptr++; + return ptr; + } + break; + } + ptr += strlen(ptr); + } + return NULL; +} + +bool efi_split_kernel_line(void) +{ + char *ptr; + + ptr = efi_cfg_get_value(EFI_CONFIG_XEN_PARSED, + SECTION_GLOBAL, ITEM_DEFAULT); + if (!ptr) + return false; + + ptr = efi_cfg_get_value(EFI_CONFIG_XEN_PARSED, + ptr, ITEM_KERNEL); + if (!ptr) + return false; + + for ( ; *ptr && !isspace(*ptr); ptr++); + + if (ptr) { + *ptr = 0; + g_kernel_cmdline = ptr + 1; + } + /* Else there is no kernel cmdline - I guess that is possible */ + + return true; +} + +bool efi_cfg_copy_tboot_path(const wchar_t *file_path) +{ + uint64_t len = wcslen(file_path); + wchar_t *ptr = g_tboot_dir + len; + + if (len >= EFI_MAX_PATH) + return false; + + memcpy(g_tboot_dir, file_path, len*sizeof(wchar_t)); + + while (ptr >= g_tboot_dir) { + if (*ptr == L'\\') { + *(ptr + 1) = L'\0'; + return true; + } + ptr--; + } + + return false; +} + +const efi_file_t *efi_get_platform_sinit(void) +{ + if (g_platform_sinit.size > 0) + return &g_platform_sinit; + return NULL; +} + +const efi_file_t *efi_get_platform_racm(void) +{ + if (g_platform_racm.size > 0) + return &g_platform_racm; + return NULL; +} + +const efi_file_t *efi_get_lcp(void) +{ + if (g_lcp.size > 0) + return &g_lcp; + return NULL; +} + +void efi_store_files(const efi_file_t *platform_sinit, + const efi_file_t *platform_racm, + const efi_file_t *lcp) +{ + memset(&g_platform_sinit, 0, sizeof(efi_file_t)); + memset(&g_platform_racm, 0, sizeof(efi_file_t)); + memset(&g_lcp, 0, sizeof(efi_file_t)); + + if (platform_sinit && platform_sinit->u.buffer) + g_platform_sinit = *platform_sinit; + if (platform_racm && platform_racm->u.buffer) + g_platform_racm = *platform_racm; + if (lcp && lcp->u.buffer) + g_lcp = *lcp; +} + +const efi_file_t *efi_get_xen(void) +{ + if (g_xen.size > 0) + return &g_xen; + return NULL; +} + +const efi_file_t *efi_get_kernel(void) +{ + if (g_kernel.size > 0) + return &g_kernel; + return NULL; +} + +const efi_file_t *efi_get_ramdisk(void) +{ + if (g_ramdisk.size > 0) + return &g_ramdisk; + return NULL; +} + +const void *efi_get_memory_map(uint64_t *size_out, uint64_t *size_desc_out) +{ + *size_out = g_memory_map_size; + *size_desc_out = g_memory_desc_size; + return g_memory_map; +} + +uint64_t efi_get_xen_post_launch_cb(void) +{ + return g_xen_post_launch_cb; +} + +void efi_store_xen_info(void *base, uint64_t size) +{ + memset(&g_xen, 0, sizeof(efi_file_t)); + g_xen.u.buffer = base; + g_xen.size = size; +} + +bool efi_store_xen_tboot_data(efi_xen_tboot_data_t *xtd) +{ + /* sanity */ + if ( (xtd->kernel == NULL) || (xtd->kernel_size == 0) || + (xtd->ramdisk == NULL) || (xtd->ramdisk_size == 0) || + (xtd->memory_map == NULL) || (xtd->memory_map_size == 0) || + (xtd->memory_desc_size == 0)) + return false; + + memset(&g_kernel, 0, sizeof(efi_file_t)); + memset(&g_ramdisk, 0, sizeof(efi_file_t)); + + g_kernel.u.buffer = xtd->kernel; + g_kernel.size = xtd->kernel_size; + g_ramdisk.u.buffer = xtd->ramdisk; + g_ramdisk.size = xtd->ramdisk_size; + g_memory_map = xtd->memory_map; + g_memory_map_size = xtd->memory_map_size; + g_memory_desc_size = xtd->memory_desc_size; + g_xen_post_launch_cb = xtd->post_launch_cb; + + return true; +} + |