From mboxrd@z Thu Jan 1 00:00:00 1970 From: AKASHI Takahiro Date: Wed, 22 Jan 2020 10:13:48 +0900 Subject: [PATCH v4 08/16] efi_loader: image_loader: support image authentication In-Reply-To: <3992a41c-8829-4636-cdbf-80b35dd96d35@gmx.de> References: <20191218004512.24939-1-takahiro.akashi@linaro.org> <20191218004512.24939-9-takahiro.akashi@linaro.org> <57d363f6-2294-c9dd-ea2c-745fe8c74865@gmx.de> <20200117051136.GL28530@linaro.org> <20200121061245.GE8146@linaro.org> <3992a41c-8829-4636-cdbf-80b35dd96d35@gmx.de> Message-ID: <20200122011347.GH8146@linaro.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Tue, Jan 21, 2020 at 08:15:06AM +0100, Heinrich Schuchardt wrote: > On 1/21/20 7:12 AM, AKASHI Takahiro wrote: > >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 > >>>>>--- > >>>>> 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 > >>>>> #include > >>>>> #include > >>>>>+#include > >>>>> > >>>>> 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 > >>>>> #include > >>>>>+#include > >>>>> #include > >>>>>+#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. > > What is the point of this patch if efi_start_image() does not provide > any check? As I said in the previous reply, efi_load_image() doesn't return any valid handle for unauthenticated binaries in my *current* implementation, efi_start_image() has no chance to execute them. No check is necessary. That's it. -Takahiro Akashi > Best regards > > Heinrich > > > > >-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; > >>>>> } > >>>>> > >>>> > >>> > >> > > >