[PATCH v4 08/16] efi_loader: image_loader: support image authentication
AKASHI Takahiro
takahiro.akashi at linaro.org
Tue Jan 21 07:12:46 CET 2020
On Fri, Jan 17, 2020 at 06:51:50AM +0100, Heinrich Schuchardt wrote:
> On 1/17/20 6:11 AM, AKASHI Takahiro wrote:
> >On Thu, Jan 09, 2020 at 12:55:17AM +0100, Heinrich Schuchardt wrote:
> >>On 12/18/19 1:45 AM, AKASHI Takahiro wrote:
> >>>With this commit, image validation can be enforced, as UEFI specification
> >>>section 32.5 describes, if CONFIG_EFI_SECURE_BOOT is enabled.
> >>>
> >>>Currently we support
> >>>* authentication based on db and dbx,
> >>> so dbx-validated image will always be rejected.
> >>>* following signature types:
> >>> EFI_CERT_SHA256_GUID (SHA256 digest for unsigned images)
> >>> EFI_CERT_X509_GUID (x509 certificate for signed images)
> >>>Timestamp-based certificate revocation is not supported here.
> >>>
> >>>Internally, authentication data is stored in one of certificates tables
> >>>of PE image (See efi_image_parse()) and will be verified by
> >>>efi_image_authenticate() before loading a given image.
> >>>
> >>>It seems that UEFI specification defines the verification process
> >>>in a bit ambiguous way. I tried to implement it as closely to as
> >>>EDK2 does.
> >>>
> >>>Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
> >>>---
> >>> include/efi_loader.h | 7 +-
> >>> lib/efi_loader/efi_boottime.c | 2 +-
> >>> lib/efi_loader/efi_image_loader.c | 454 +++++++++++++++++++++++++++++-
> >>> 3 files changed, 449 insertions(+), 14 deletions(-)
> >>>
> >>>diff --git a/include/efi_loader.h b/include/efi_loader.h
> >>>index 1f88caf86709..e12b49098fb0 100644
> >>>--- a/include/efi_loader.h
> >>>+++ b/include/efi_loader.h
> >>>@@ -11,6 +11,7 @@
> >>> #include <common.h>
> >>> #include <part_efi.h>
> >>> #include <efi_api.h>
> >>>+#include <pe.h>
> >>>
> >>> static inline int guidcmp(const void *g1, const void *g2)
> >>> {
> >>>@@ -398,7 +399,8 @@ efi_status_t efi_set_watchdog(unsigned long timeout);
> >>> /* Called from places to check whether a timer expired */
> >>> void efi_timer_check(void);
> >>> /* PE loader implementation */
> >>>-efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
> >>>+efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle,
> >>>+ void *efi, size_t efi_size,
> >>> struct efi_loaded_image *loaded_image_info);
> >>> /* Called once to store the pristine gd pointer */
> >>> void efi_save_gd(void);
> >>>@@ -726,6 +728,9 @@ void efi_sigstore_free(struct efi_signature_store *sigstore);
> >>> struct efi_signature_store *efi_sigstore_parse_sigdb(u16 *name);
> >>>
> >>> bool efi_secure_boot_enabled(void);
> >>>+
> >>>+bool efi_image_parse(void *efi, size_t len, struct efi_image_regions **regp,
> >>>+ WIN_CERTIFICATE **auth, size_t *auth_len);
> >>> #endif /* CONFIG_EFI_SECURE_BOOT */
> >>>
> >>> #else /* CONFIG_IS_ENABLED(EFI_LOADER) */
> >>>diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
> >>>index 493d906c641d..311681764034 100644
> >>>--- a/lib/efi_loader/efi_boottime.c
> >>>+++ b/lib/efi_loader/efi_boottime.c
> >>>@@ -1879,7 +1879,7 @@ efi_status_t EFIAPI efi_load_image(bool boot_policy,
> >>> efi_dp_split_file_path(file_path, &dp, &fp);
> >>> ret = efi_setup_loaded_image(dp, fp, image_obj, &info);
> >>> if (ret == EFI_SUCCESS)
> >>>- ret = efi_load_pe(*image_obj, dest_buffer, info);
> >>>+ ret = efi_load_pe(*image_obj, dest_buffer, source_size, info);
> >>> if (!source_buffer)
> >>> /* Release buffer to which file was loaded */
> >>> efi_free_pages((uintptr_t)dest_buffer,
> >>>diff --git a/lib/efi_loader/efi_image_loader.c b/lib/efi_loader/efi_image_loader.c
> >>>index 13541cfa7a28..939758e61e3c 100644
> >>>--- a/lib/efi_loader/efi_image_loader.c
> >>>+++ b/lib/efi_loader/efi_image_loader.c
> >>>@@ -9,7 +9,9 @@
> >>>
> >>> #include <common.h>
> >>> #include <efi_loader.h>
> >>>+#include <malloc.h>
> >>> #include <pe.h>
> >>>+#include "../lib/crypto/pkcs7_parser.h"
> >>>
> >>> const efi_guid_t efi_global_variable_guid = EFI_GLOBAL_VARIABLE_GUID;
> >>> const efi_guid_t efi_guid_device_path = EFI_DEVICE_PATH_PROTOCOL_GUID;
> >>>@@ -205,6 +207,367 @@ static void efi_set_code_and_data_type(
> >>> }
> >>> }
> >>>
> >>>+#ifdef CONFIG_EFI_SECURE_BOOT
> >>>+/**
> >>>+ * efi_image_parse - parse a PE image
> >>>+ * @efi: Pointer to image
> >>>+ * @len: Size of @efi
> >>>+ * @regs: Pointer to a list of regions
> >>>+ * @auth: Pointer to a pointer to authentication data in PE
> >>>+ * @auth_len: Size of @auth
> >>>+ *
> >>>+ * Parse image binary in PE32(+) format, assuming that sanity of PE image
> >>>+ * has been checked by a caller.
> >>>+ * On success, an address of authentication data in @efi and its size will
> >>>+ * be returned in @auth and @auth_len, respectively.
> >>>+ *
> >>>+ * Return: true on success, false on error
> >>>+ */
> >>>+bool efi_image_parse(void *efi, size_t len, struct efi_image_regions **regp,
> >>>+ WIN_CERTIFICATE **auth, size_t *auth_len)
> >>
> >>
> >>This function is way too long (> 100 lines). Please, cut it into logical
> >>units.
> >>
> >>
> >>
> >>>+{
> >>>+ struct efi_image_regions *regs;
> >>>+ IMAGE_DOS_HEADER *dos;
> >>>+ IMAGE_NT_HEADERS32 *nt;
> >>>+ IMAGE_SECTION_HEADER *sections, **sorted;
> >>>+ int num_regions, num_sections, i, j;
> >>>+ int ctidx = IMAGE_DIRECTORY_ENTRY_SECURITY;
> >>>+ u32 align, size, authsz, authoff;
> >>>+ size_t bytes_hashed;
> >>>+
> >>>+ dos = (void *)efi;
> >>>+ nt = (void *)(efi + dos->e_lfanew);
> >>>+
> >>>+ /*
> >>>+ * Count maximum number of regions to be digested.
> >>>+ * We don't have to have an exact number here.
> >>>+ * See efi_image_region_add()'s in parsing below.
> >>>+ */
> >>>+ num_regions = 3; /* for header */
> >>>+ num_regions += nt->FileHeader.NumberOfSections;
> >>>+ num_regions++; /* for extra */
> >>>+
> >>>+ regs = calloc(sizeof(*regs) + sizeof(struct image_region) * num_regions,
> >>>+ 1);
> >>>+ if (!regs)
> >>>+ goto err;
> >>>+ regs->max = num_regions;
> >>>+
> >>>+ /*
> >>>+ * Collect data regions for hash calculation
> >>>+ * 1. File headers
> >>>+ */
> >>>+ if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
> >>>+ IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
> >>>+ IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
> >>>+
> >>>+ /* Skip CheckSum */
> >>>+ efi_image_region_add(regs, efi, &opt->CheckSum, 0);
> >>>+ if (nt64->OptionalHeader.NumberOfRvaAndSizes <= ctidx) {
> >>>+ efi_image_region_add(regs,
> >>>+ &opt->CheckSum + 1,
> >>>+ efi + opt->SizeOfHeaders, 0);
> >>>+ } else {
> >>>+ /* Skip Certificates Table */
> >>>+ efi_image_region_add(regs,
> >>>+ &opt->CheckSum + 1,
> >>>+ &opt->DataDirectory[ctidx], 0);
> >>>+ efi_image_region_add(regs,
> >>>+ &opt->DataDirectory[ctidx] + 1,
> >>>+ efi + opt->SizeOfHeaders, 0);
> >>>+ }
> >>>+
> >>>+ bytes_hashed = opt->SizeOfHeaders;
> >>>+ align = opt->FileAlignment;
> >>>+ authoff = opt->DataDirectory[ctidx].VirtualAddress;
> >>>+ authsz = opt->DataDirectory[ctidx].Size;
> >>>+ } else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
> >>>+ IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
> >>>+
> >>>+ efi_image_region_add(regs, efi, &opt->CheckSum, 0);
> >>>+ efi_image_region_add(regs, &opt->CheckSum + 1,
> >>>+ &opt->DataDirectory[ctidx], 0);
> >>>+ efi_image_region_add(regs, &opt->DataDirectory[ctidx] + 1,
> >>>+ efi + opt->SizeOfHeaders, 0);
> >>>+
> >>>+ bytes_hashed = opt->SizeOfHeaders;
> >>>+ align = opt->FileAlignment;
> >>>+ authoff = opt->DataDirectory[ctidx].VirtualAddress;
> >>>+ authsz = opt->DataDirectory[ctidx].Size;
> >>>+ } else {
> >>>+ debug("%s: Invalid optional header magic %x\n", __func__,
> >>>+ nt->OptionalHeader.Magic);
> >>>+ goto err;
> >>>+ }
> >>>+
> >>>+ /* 2. Sections */
> >>>+ num_sections = nt->FileHeader.NumberOfSections;
> >>>+ sections = (void *)((uint8_t *)&nt->OptionalHeader +
> >>>+ nt->FileHeader.SizeOfOptionalHeader);
> >>>+ sorted = calloc(sizeof(IMAGE_SECTION_HEADER *), num_sections);
> >>>+ if (!sorted) {
> >>>+ debug("%s: Out of memory\n", __func__);
> >>>+ goto err;
> >>>+ }
> >>>+
> >>>+ /*
> >>>+ * Make sure the section list is in ascending order.
> >>>+ * As we can assume that it is already ordered in most cases,
> >>>+ * the following code is optimized for this.
> >>>+ */
> >>>+ for (sorted[0] = §ions[0], i = 1; i < num_sections; i++) {
> >>
> >>If sections[0] is not the lowest entry this function fails.
> >>
> >>Please, use qsort() supplied in lib/qsort.c.
> >
> >I'd rather fix my code as it is much simpler than qsort.
>
> Using qsort will result in a smaller code size. With qsort your code
> will also be much easier to read.
>
> >
> >>>+ if (sorted[i - 1]->VirtualAddress
> >>>+ <= sections[i].VirtualAddress) {
> >>>+ sorted[i] = §ions[i];
> >>>+ } else {
> >>>+ if (i == 1) {
> >>>+ sorted[1] = sorted[0];
> >>>+ sorted[0] = §ions[1];
> >>>+ continue;
> >>>+ }
> >>>+
> >>>+ sorted[i] = sorted[i - 1];
> >>>+ for (j = i - 2; j >= 0; j--) {
> >>>+ if (!j || sorted[j]->VirtualAddress
> >>>+ <= sections[i].VirtualAddress) {
> >>>+ sorted[j + 1] = §ions[i];
> >>>+ continue;
> >>>+ } else {
> >>>+ sorted[j + 1] = sorted[j];
> >>>+ }
> >>>+ }
> >>>+ }
> >>>+ }
> >>>+
> >>>+ for (i = 0; i < num_sections; i++) {
> >>>+ if (!sorted[i]->SizeOfRawData)
> >>>+ continue;
> >>>+
> >>>+ size = (sorted[i]->SizeOfRawData + align - 1) & ~(align - 1);
> >>>+ efi_image_region_add(regs, efi + sorted[i]->PointerToRawData,
> >>>+ efi + sorted[i]->PointerToRawData + size,
> >>>+ 0);
> >>>+ debug("section[%d](%s): raw: 0x%x-0x%x, virt: %x-%x\n",
> >>>+ i, sorted[i]->Name,
> >>>+ sorted[i]->PointerToRawData,
> >>>+ sorted[i]->PointerToRawData + size,
> >>>+ sorted[i]->VirtualAddress,
> >>>+ sorted[i]->VirtualAddress
> >>>+ + sorted[i]->Misc.VirtualSize);
> >>>+
> >>>+ bytes_hashed += size;
> >>>+ }
> >>>+ free(sorted);
> >>>+
> >>>+ /* 3. Extra data excluding Certificates Table */
> >>>+ if (bytes_hashed + authsz < len) {
> >>>+ debug("extra data for hash: %lu\n",
> >>>+ len - (bytes_hashed + authsz));
> >>>+ efi_image_region_add(regs, efi + bytes_hashed,
> >>>+ efi + len - authsz, 0);
> >>>+ }
> >>>+
> >>>+ /* Return Certificates Table */
> >>>+ if (authsz) {
> >>>+ if (len < authoff + authsz) {
> >>>+ debug("%s: Size for auth too large: %u >= %zu\n",
> >>>+ __func__, authsz, len - authoff);
> >>>+ goto err;
> >>>+ }
> >>>+ if (authsz < sizeof(*auth)) {
> >>>+ debug("%s: Size for auth too small: %u < %zu\n",
> >>>+ __func__, authsz, sizeof(*auth));
> >>>+ goto err;
> >>>+ }
> >>>+ *auth = efi + authoff;
> >>>+ *auth_len = authsz;
> >>>+ debug("WIN_CERTIFICATE: 0x%x, size: 0x%x\n", authoff, authsz);
> >>>+ } else {
> >>>+ *auth = NULL;
> >>>+ *auth_len = 0;
> >>>+ }
> >>>+
> >>>+ *regp = regs;
> >>>+
> >>>+ return true;
> >>>+
> >>>+err:
> >>>+ free(regs);
> >>>+
> >>>+ return false;
> >>>+}
> >>>+
> >>>+/**
> >>>+ * efi_image_unsigned_authenticate - authenticate unsigned image with
> >>>+ * SHA256 hash
> >>>+ * @regs: List of regions to be verified
> >>>+ *
> >>>+ * If an image is not signed, it doesn't have a signature. In this case,
> >>>+ * its message digest is calculated and it will be compared with one of
> >>>+ * hash values stored in signature databases.
> >>>+ *
> >>>+ * Return: true if authenticated, false if not
> >>>+ */
> >>>+static bool efi_image_unsigned_authenticate(struct efi_image_regions *regs)
> >>>+{
> >>>+ struct efi_signature_store *db = NULL, *dbx = NULL;
> >>>+ bool ret = false;
> >>>+
> >>>+ dbx = efi_sigstore_parse_sigdb(L"dbx");
> >>>+ if (!dbx) {
> >>>+ debug("Getting signature database(dbx) failed\n");
> >>>+ goto out;
> >>>+ }
> >>>+
> >>>+ db = efi_sigstore_parse_sigdb(L"db");
> >>>+ if (!db) {
> >>>+ debug("Getting signature database(db) failed\n");
> >>>+ goto out;
> >>>+ }
> >>>+
> >>>+ /* try black-list first */
> >>>+ if (efi_signature_verify_with_sigdb(regs, NULL, dbx, NULL)) {
> >>>+ debug("Image is not signed and rejected by \"dbx\"\n");
> >>>+ goto out;
> >>>+ }
> >>>+
> >>>+ /* try white-list */
> >>>+ if (efi_signature_verify_with_sigdb(regs, NULL, db, NULL))
> >>>+ ret = true;
> >>>+ else
> >>>+ debug("Image is not signed and not found in \"db\" or \"dbx\"\n");
> >>>+
> >>>+out:
> >>>+ efi_sigstore_free(db);
> >>>+ efi_sigstore_free(dbx);
> >>>+
> >>>+ return ret;
> >>>+}
> >>>+
> >>>+/**
> >>>+ * efi_image_authenticate - verify a signature of signed image
> >>>+ * @efi: Pointer to image
> >>>+ * @len: Size of @efi
> >>>+ *
> >>>+ * A signed image should have its signature stored in a table of its PE header.
> >>>+ * So if an image is signed and only if if its signature is verified using
> >>>+ * signature databases, an image is authenticated.
> >>>+ * If an image is not signed, its validity is checked by using
> >>>+ * efi_image_unsigned_authenticated().
> >>>+ * TODO:
> >>>+ * When AuditMode==0, if the image's signature is not found in
> >>>+ * the authorized database, or is found in the forbidden database,
> >>>+ * the image will not be started and instead, information about it
> >>>+ * will be placed in this table.
> >>>+ * When AuditMode==1, an EFI_IMAGE_EXECUTION_INFO element is created
> >>>+ * in the EFI_IMAGE_EXECUTION_INFO_TABLE for every certificate found
> >>>+ * in the certificate table of every image that is validated.
> >>>+ *
> >>>+ * Return: true if authenticated, false if not
> >>>+ */
> >>>+static bool efi_image_authenticate(void *efi, size_t len)
> >>>+{
> >>>+ struct efi_image_regions *regs = NULL;
> >>>+ WIN_CERTIFICATE *wincerts = NULL, *wincert;
> >>>+ size_t wincerts_len;
> >>>+ struct pkcs7_message *msg = NULL;
> >>>+ struct efi_signature_store *db = NULL, *dbx = NULL;
> >>>+ struct x509_certificate *cert = NULL;
> >>>+ bool ret = false;
> >>>+
> >>>+ if (!efi_secure_boot_enabled())
> >>>+ return true;
> >>>+
> >>>+ if (!efi_image_parse(efi, len, ®s, &wincerts,
> >>>+ &wincerts_len)) {
> >>>+ debug("Parsing PE executable image failed\n");
> >>>+ return false;
> >>>+ }
> >>>+
> >>>+ if (!wincerts) {
> >>>+ /* The image is not signed */
> >>>+ ret = efi_image_unsigned_authenticate(regs);
> >>>+ free(regs);
> >>>+
> >>>+ return ret;
> >>>+ }
> >>>+
> >>>+ /*
> >>>+ * verify signature using db and dbx
> >>>+ */
> >>>+ db = efi_sigstore_parse_sigdb(L"db");
> >>>+ if (!db) {
> >>>+ debug("Getting signature database(db) failed\n");
> >>>+ goto err;
> >>>+ }
> >>>+
> >>>+ dbx = efi_sigstore_parse_sigdb(L"dbx");
> >>>+ if (!dbx) {
> >>>+ debug("Getting signature database(dbx) failed\n");
> >>>+ goto err;
> >>>+ }
> >>>+
> >>>+ /* go through WIN_CERTIFICATE list */
> >>>+ for (wincert = wincerts;
> >>>+ (void *)wincert < (void *)wincerts + wincerts_len;
> >>>+ wincert = (void *)wincert + ALIGN(wincert->dwLength, 8)) {
> >>>+ if (wincert->dwLength < sizeof(*wincert)) {
> >>>+ debug("%s: dwLength too small: %u < %zu\n",
> >>>+ __func__, wincert->dwLength, sizeof(*wincert));
> >>>+ goto err;
> >>>+ }
> >>>+ msg = pkcs7_parse_message((void *)wincert + sizeof(*wincert),
> >>>+ wincert->dwLength - sizeof(*wincert));
> >>>+ if (!msg) {
> >>>+ debug("Parsing image's signature failed\n");
> >>>+ goto err;
> >>>+ }
> >>>+
> >>>+ /* try black-list first */
> >>>+ if (efi_signature_verify_with_sigdb(regs, msg, dbx, NULL)) {
> >>>+ debug("Signature was rejected by \"dbx\"\n");
> >>>+ goto err;
> >>>+ }
> >>>+
> >>>+ if (!efi_signature_verify_signers(msg, dbx)) {
> >>>+ debug("Signer was rejected by \"dbx\"\n");
> >>>+ goto err;
> >>>+ } else {
> >>>+ ret = true;
> >>>+ }
> >>>+
> >>>+ /* try white-list */
> >>>+ if (!efi_signature_verify_with_sigdb(regs, msg, db, &cert)) {
> >>>+ debug("Verifying signature with \"db\" failed\n");
> >>>+ goto err;
> >>>+ } else {
> >>>+ ret = true;
> >>>+ }
> >>>+
> >>>+ if (!efi_signature_verify_cert(cert, dbx)) {
> >>>+ debug("Certificate was rejected by \"dbx\"\n");
> >>>+ goto err;
> >>>+ } else {
> >>>+ ret = true;
> >>>+ }
> >>>+ }
> >>>+
> >>>+err:
> >>>+ x509_free_certificate(cert);
> >>>+ efi_sigstore_free(db);
> >>>+ efi_sigstore_free(dbx);
> >>>+ pkcs7_free_message(msg);
> >>>+ free(regs);
> >>>+
> >>>+ return ret;
> >>>+}
> >>>+#else
> >>>+static bool efi_image_authenticate(void *efi, size_t len)
> >>>+{
> >>>+ return true;
> >>>+}
> >>>+#endif /* CONFIG_EFI_SECURE_BOOT */
> >>>+
> >>> /**
> >>> * efi_load_pe() - relocate EFI binary
> >>> *
> >>>@@ -216,7 +579,8 @@ static void efi_set_code_and_data_type(
> >>> * @loaded_image_info: loaded image protocol
> >>> * Return: status code
> >>> */
> >>>-efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
> >>>+efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle,
> >>>+ void *efi, size_t efi_size,
> >>> struct efi_loaded_image *loaded_image_info)
> >>> {
> >>> IMAGE_NT_HEADERS32 *nt;
> >>>@@ -231,17 +595,57 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
> >>> uint64_t image_base;
> >>> unsigned long virt_size = 0;
> >>> int supported = 0;
> >>>+ void *new_efi = NULL;
> >>>+ size_t new_efi_size;
> >>>+ efi_status_t ret;
> >>>+
> >>>+ /*
> >>>+ * Size must be 8-byte aligned and the trailing bytes must be
> >>>+ * zero'ed. Otherwise hash value may be incorrect.
> >>>+ */
> >>>+ if (efi_size & 0x7) {
> >>>+ new_efi_size = (efi_size + 0x7) & ~0x7ULL;
> >>>+ new_efi = calloc(new_efi_size, 1);
> >>>+ if (!new_efi)
> >>>+ return EFI_OUT_OF_RESOURCES;
> >>>+ memcpy(new_efi, efi, efi_size);
> >>>+ efi = new_efi;
> >>>+ efi_size = new_efi_size;
> >>>+ }
> >>>+
> >>>+ /* Sanity check for a file header */
> >>>+ if (efi_size < sizeof(*dos)) {
> >>>+ printf("%s: Truncated DOS Header\n", __func__);
> >>>+ ret = EFI_LOAD_ERROR;
> >>>+ goto err;
> >>>+ }
> >>>
> >>> dos = efi;
> >>> if (dos->e_magic != IMAGE_DOS_SIGNATURE) {
> >>> printf("%s: Invalid DOS Signature\n", __func__);
> >>>- return EFI_LOAD_ERROR;
> >>>+ ret = EFI_LOAD_ERROR;
> >>>+ goto err;
> >>>+ }
> >>>+
> >>>+ /* assume sizeof(IMAGE_NT_HEADERS32) <= sizeof(IMAGE_NT_HEADERS64) */
> >>>+ if (efi_size < dos->e_lfanew + sizeof(IMAGE_NT_HEADERS32)) {
> >>>+ printf("%s: Invalid offset for Extended Header\n", __func__);
> >>>+ ret = EFI_LOAD_ERROR;
> >>>+ goto err;
> >>> }
> >>>
> >>> nt = (void *) ((char *)efi + dos->e_lfanew);
> >>>+ if ((nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) &&
> >>>+ (efi_size < dos->e_lfanew + sizeof(IMAGE_NT_HEADERS64))) {
> >>>+ printf("%s: Invalid offset for Extended Header\n", __func__);
> >>>+ ret = EFI_LOAD_ERROR;
> >>>+ goto err;
> >>>+ }
> >>>+
> >>> if (nt->Signature != IMAGE_NT_SIGNATURE) {
> >>> printf("%s: Invalid NT Signature\n", __func__);
> >>>- return EFI_LOAD_ERROR;
> >>>+ ret = EFI_LOAD_ERROR;
> >>>+ goto err;
> >>> }
> >>>
> >>> for (i = 0; machines[i]; i++)
> >>>@@ -253,14 +657,29 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
> >>> if (!supported) {
> >>> printf("%s: Machine type 0x%04x is not supported\n",
> >>> __func__, nt->FileHeader.Machine);
> >>>- return EFI_LOAD_ERROR;
> >>>+ ret = EFI_LOAD_ERROR;
> >>>+ goto err;
> >>> }
> >>>
> >>>- /* Calculate upper virtual address boundary */
> >>> num_sections = nt->FileHeader.NumberOfSections;
> >>> sections = (void *)&nt->OptionalHeader +
> >>> nt->FileHeader.SizeOfOptionalHeader;
> >>>
> >>>+ if (efi_size < ((void *)sections + sizeof(sections[0]) * num_sections
> >>>+ - efi)) {
> >>>+ printf("%s: Invalid number of sections: %d\n",
> >>>+ __func__, num_sections);
> >>>+ ret = EFI_LOAD_ERROR;
> >>>+ goto err;
> >>>+ }
> >>>+
> >>>+ /* Authenticate an image */
> >>>+ if (!efi_image_authenticate(efi, efi_size)) {
> >>>+ ret = EFI_ACCESS_DENIED;
> >>
> >>According to the UEFI specification LoadImage() should return
> >>EFI_SECURITY_VIOLATION in this case.
> >
> >Will check.
> >
> >>Further behaviour should depend on variables AuditMode and DeployedMode.
> >>
> >>If authentication fails, you must update the configuration table
> >>identified by EFI_IMAGE_SECURITY_DATABASE_GUID containing the Image
> >>Execution Information. If the authentication succeeds you may enter a
> >>record.
> >>
> >>It seems to me that in your patch series you are not creating the
> >>configuration table at all.
> >
> >>From the very beginning of my submissions, I have clearly said
> >that this feature was *beyond the scope* in my current series.
> >===8<===
> >Unsupported features: (marked as TODO in most cases in the source code,
> > and won't be included in this series)
> >(snip)
> >* recording rejected images in EFI_IMAGE_EXECUTION_INFO_TABLE
> >===>8===
> >
> >>The content of the Image Execution Information Table should be used to
> >>decide if StartImage() may start an image. This is still missing in the
> >>patch series.
> >
> >No.
> >Whether such information be in configuration table or not,
> >non-authenticated image won't be started if secure boot is in force.
>
> I cannot find any such check in efi_start_image().
Because my current code *rejects* any unauthenticated images being loaded
and return no valid pointer to image handle.
If an error code in this case is changed and efi_load_image() still returns
a valid handle, we will also have to modify efi_start_image().
> Please, provide an implementation that complies with the UEFI specification:
>
> "The information is used to create the Image Execution Information
> Table, which is added to the EFI System Configuration Table and assigned
> the GUID EFI_IMAGE_SECURITY_DATABASE_GUID."
Regarding "Image Execution Information Table", Heavily disagree.
The current UEFI code, not only mine but yours, has bunch of unimplemented
features.
-Takahiro Akashi
> Best regards
>
> Heinrich
>
> >
> >Thanks,
> >-Takahiro Akashi
> >
> >>
> >>Best regards
> >>
> >>Heinrich
> >>
> >>>+ goto err;
> >>>+ }
> >>>+
> >>>+ /* Calculate upper virtual address boundary */
> >>> for (i = num_sections - 1; i >= 0; i--) {
> >>> IMAGE_SECTION_HEADER *sec = §ions[i];
> >>> virt_size = max_t(unsigned long, virt_size,
> >>>@@ -279,7 +698,8 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
> >>> if (!efi_reloc) {
> >>> printf("%s: Could not allocate %lu bytes\n",
> >>> __func__, virt_size);
> >>>- return EFI_OUT_OF_RESOURCES;
> >>>+ ret = EFI_OUT_OF_RESOURCES;
> >>>+ goto err;
> >>> }
> >>> handle->entry = efi_reloc + opt->AddressOfEntryPoint;
> >>> rel_size = opt->DataDirectory[rel_idx].Size;
> >>>@@ -295,7 +715,8 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
> >>> if (!efi_reloc) {
> >>> printf("%s: Could not allocate %lu bytes\n",
> >>> __func__, virt_size);
> >>>- return EFI_OUT_OF_RESOURCES;
> >>>+ ret = EFI_OUT_OF_RESOURCES;
> >>>+ goto err;
> >>> }
> >>> handle->entry = efi_reloc + opt->AddressOfEntryPoint;
> >>> rel_size = opt->DataDirectory[rel_idx].Size;
> >>>@@ -304,13 +725,16 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
> >>> } else {
> >>> printf("%s: Invalid optional header magic %x\n", __func__,
> >>> nt->OptionalHeader.Magic);
> >>>- return EFI_LOAD_ERROR;
> >>>+ ret = EFI_LOAD_ERROR;
> >>>+ goto err;
> >>> }
> >>>
> >>> /* Copy PE headers */
> >>>- memcpy(efi_reloc, efi, sizeof(*dos) + sizeof(*nt)
> >>>- + nt->FileHeader.SizeOfOptionalHeader
> >>>- + num_sections * sizeof(IMAGE_SECTION_HEADER));
> >>>+ memcpy(efi_reloc, efi,
> >>>+ sizeof(*dos)
> >>>+ + sizeof(*nt)
> >>>+ + nt->FileHeader.SizeOfOptionalHeader
> >>>+ + num_sections * sizeof(IMAGE_SECTION_HEADER));
> >>>
> >>> /* Load sections into RAM */
> >>> for (i = num_sections - 1; i >= 0; i--) {
> >>>@@ -327,7 +751,8 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
> >>> (unsigned long)image_base) != EFI_SUCCESS) {
> >>> efi_free_pages((uintptr_t) efi_reloc,
> >>> (virt_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT);
> >>>- return EFI_LOAD_ERROR;
> >>>+ ret = EFI_LOAD_ERROR;
> >>>+ goto err;
> >>> }
> >>>
> >>> /* Flush cache */
> >>>@@ -340,4 +765,9 @@ efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle, void *efi,
> >>> loaded_image_info->image_size = virt_size;
> >>>
> >>> return EFI_SUCCESS;
> >>>+
> >>>+err:
> >>>+ free(new_efi);
> >>>+
> >>>+ return ret;
> >>> }
> >>>
> >>
> >
>
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