diff options
Diffstat (limited to 'firmware/2lib/2common.c')
| -rw-r--r-- | firmware/2lib/2common.c | 260 |
1 files changed, 0 insertions, 260 deletions
diff --git a/firmware/2lib/2common.c b/firmware/2lib/2common.c index e15ddb77..9e75d0c3 100644 --- a/firmware/2lib/2common.c +++ b/firmware/2lib/2common.c @@ -110,267 +110,7 @@ void vb2_workbuf_free(struct vb2_workbuf *wb, uint32_t size) wb->size += size; } -uint8_t *vb2_signature_data(struct vb2_signature *sig) -{ - return (uint8_t *)sig + sig->sig_offset; -} - ptrdiff_t vb2_offset_of(const void *base, const void *ptr) { return (uintptr_t)ptr - (uintptr_t)base; } - -int vb2_verify_member_inside(const void *parent, size_t parent_size, - const void *member, size_t member_size, - ptrdiff_t member_data_offset, - size_t member_data_size) -{ - const uintptr_t parent_end = (uintptr_t)parent + parent_size; - const ptrdiff_t member_offs = vb2_offset_of(parent, member); - const ptrdiff_t member_end_offs = member_offs + member_size; - const ptrdiff_t data_offs = member_offs + member_data_offset; - const ptrdiff_t data_end_offs = data_offs + member_data_size; - - /* Make sure parent doesn't wrap */ - if (parent_size < 0 || parent_end < (uintptr_t)parent) - return VB2_ERROR_INSIDE_PARENT_WRAPS; - - /* - * Make sure the member is fully contained in the parent and doesn't - * wrap. Use >, not >=, since member_size = 0 is possible. - */ - if (member_size < 0 || member_end_offs < member_offs) - return VB2_ERROR_INSIDE_MEMBER_WRAPS; - if (member_offs < 0 || member_offs > parent_size || - member_end_offs > parent_size) - return VB2_ERROR_INSIDE_MEMBER_OUTSIDE; - - /* Make sure the member data is after the member */ - if (member_data_size > 0 && data_offs < member_end_offs) - return VB2_ERROR_INSIDE_DATA_OVERLAP; - - /* Make sure parent fully contains member data, if any */ - if (member_data_size < 0 || data_end_offs < data_offs) - return VB2_ERROR_INSIDE_DATA_WRAPS; - if (data_offs < 0 || data_offs > parent_size || - data_end_offs > parent_size) - return VB2_ERROR_INSIDE_DATA_OUTSIDE; - - return VB2_SUCCESS; -} - -int vb2_verify_signature_inside(const void *parent, - uint32_t parent_size, - const struct vb2_signature *sig) -{ - return vb2_verify_member_inside(parent, parent_size, - sig, sizeof(*sig), - sig->sig_offset, sig->sig_size); -} - -int vb2_verify_digest(const struct vb2_public_key *key, - struct vb2_signature *sig, - const uint8_t *digest, - const struct vb2_workbuf *wb) -{ - uint8_t *sig_data = vb2_signature_data(sig); - - if (sig->sig_size != vb2_rsa_sig_size(key->sig_alg)) { - VB2_DEBUG("Wrong data signature size for algorithm, " - "sig_size=%d, expected %d for algorithm %d.\n", - sig->sig_size, vb2_rsa_sig_size(key->sig_alg), - key->sig_alg); - return VB2_ERROR_VDATA_SIG_SIZE; - } - - return vb2_rsa_verify_digest(key, sig_data, digest, wb); -} - -int vb2_verify_data(const uint8_t *data, - uint32_t size, - struct vb2_signature *sig, - const struct vb2_public_key *key, - const struct vb2_workbuf *wb) -{ - struct vb2_workbuf wblocal = *wb; - struct vb2_digest_context *dc; - uint8_t *digest; - uint32_t digest_size; - int rv; - - if (sig->data_size > size) { - VB2_DEBUG("Data buffer smaller than length of signed data.\n"); - return VB2_ERROR_VDATA_NOT_ENOUGH_DATA; - } - - /* Digest goes at start of work buffer */ - digest_size = vb2_digest_size(key->hash_alg); - if (!digest_size) - return VB2_ERROR_VDATA_DIGEST_SIZE; - - digest = vb2_workbuf_alloc(&wblocal, digest_size); - if (!digest) - return VB2_ERROR_VDATA_WORKBUF_DIGEST; - - /* Hashing requires temp space for the context */ - dc = vb2_workbuf_alloc(&wblocal, sizeof(*dc)); - if (!dc) - return VB2_ERROR_VDATA_WORKBUF_HASHING; - - rv = vb2_digest_init(dc, key->hash_alg); - if (rv) - return rv; - - rv = vb2_digest_extend(dc, data, sig->data_size); - if (rv) - return rv; - - rv = vb2_digest_finalize(dc, digest, digest_size); - if (rv) - return rv; - - vb2_workbuf_free(&wblocal, sizeof(*dc)); - - return vb2_verify_digest(key, sig, digest, &wblocal); -} - -int vb2_verify_keyblock(struct vb2_keyblock *block, - uint32_t size, - const struct vb2_public_key *key, - const struct vb2_workbuf *wb) -{ - struct vb2_signature *sig; - int rv; - - /* Sanity checks before attempting signature of data */ - if(size < sizeof(*block)) { - VB2_DEBUG("Not enough space for key block header.\n"); - return VB2_ERROR_KEYBLOCK_TOO_SMALL_FOR_HEADER; - } - if (memcmp(block->magic, KEY_BLOCK_MAGIC, KEY_BLOCK_MAGIC_SIZE)) { - VB2_DEBUG("Not a valid verified boot key block.\n"); - return VB2_ERROR_KEYBLOCK_MAGIC; - } - if (block->header_version_major != KEY_BLOCK_HEADER_VERSION_MAJOR) { - VB2_DEBUG("Incompatible key block header version.\n"); - return VB2_ERROR_KEYBLOCK_HEADER_VERSION; - } - if (size < block->keyblock_size) { - VB2_DEBUG("Not enough data for key block.\n"); - return VB2_ERROR_KEYBLOCK_SIZE; - } - - /* Check signature */ - sig = &block->keyblock_signature; - - if (vb2_verify_signature_inside(block, block->keyblock_size, sig)) { - VB2_DEBUG("Key block signature off end of block\n"); - return VB2_ERROR_KEYBLOCK_SIG_OUTSIDE; - } - - /* Make sure advertised signature data sizes are sane. */ - if (block->keyblock_size < sig->data_size) { - VB2_DEBUG("Signature calculated past end of block\n"); - return VB2_ERROR_KEYBLOCK_SIGNED_TOO_MUCH; - } - - VB2_DEBUG("Checking key block signature...\n"); - rv = vb2_verify_data((const uint8_t *)block, size, sig, key, wb); - if (rv) { - VB2_DEBUG("Invalid key block signature.\n"); - return VB2_ERROR_KEYBLOCK_SIG_INVALID; - } - - /* Verify we signed enough data */ - if (sig->data_size < sizeof(struct vb2_keyblock)) { - VB2_DEBUG("Didn't sign enough data\n"); - return VB2_ERROR_KEYBLOCK_SIGNED_TOO_LITTLE; - } - - /* Verify data key is inside the block and inside signed data */ - if (vb2_verify_packed_key_inside(block, block->keyblock_size, - &block->data_key)) { - VB2_DEBUG("Data key off end of key block\n"); - return VB2_ERROR_KEYBLOCK_DATA_KEY_OUTSIDE; - } - if (vb2_verify_packed_key_inside(block, sig->data_size, - &block->data_key)) { - VB2_DEBUG("Data key off end of signed data\n"); - return VB2_ERROR_KEYBLOCK_DATA_KEY_UNSIGNED; - } - - /* Success */ - return VB2_SUCCESS; -} - -int vb2_verify_fw_preamble(struct vb2_fw_preamble *preamble, - uint32_t size, - const struct vb2_public_key *key, - const struct vb2_workbuf *wb) -{ - struct vb2_signature *sig = &preamble->preamble_signature; - - VB2_DEBUG("Verifying preamble.\n"); - - /* Sanity checks before attempting signature of data */ - if(size < sizeof(*preamble)) { - VB2_DEBUG("Not enough data for preamble header\n"); - return VB2_ERROR_PREAMBLE_TOO_SMALL_FOR_HEADER; - } - if (preamble->header_version_major != - FIRMWARE_PREAMBLE_HEADER_VERSION_MAJOR) { - VB2_DEBUG("Incompatible firmware preamble header version.\n"); - return VB2_ERROR_PREAMBLE_HEADER_VERSION; - } - - if (preamble->header_version_minor < 1) { - VB2_DEBUG("Only preamble header 2.1+ supported\n"); - return VB2_ERROR_PREAMBLE_HEADER_OLD; - } - - if (size < preamble->preamble_size) { - VB2_DEBUG("Not enough data for preamble.\n"); - return VB2_ERROR_PREAMBLE_SIZE; - } - - /* Check signature */ - if (vb2_verify_signature_inside(preamble, preamble->preamble_size, - sig)) { - VB2_DEBUG("Preamble signature off end of preamble\n"); - return VB2_ERROR_PREAMBLE_SIG_OUTSIDE; - } - - /* Make sure advertised signature data sizes are sane. */ - if (preamble->preamble_size < sig->data_size) { - VB2_DEBUG("Signature calculated past end of the block\n"); - return VB2_ERROR_PREAMBLE_SIGNED_TOO_MUCH; - } - - if (vb2_verify_data((const uint8_t *)preamble, size, sig, key, wb)) { - VB2_DEBUG("Preamble signature validation failed\n"); - return VB2_ERROR_PREAMBLE_SIG_INVALID; - } - - /* Verify we signed enough data */ - if (sig->data_size < sizeof(struct vb2_fw_preamble)) { - VB2_DEBUG("Didn't sign enough data\n"); - return VB2_ERROR_PREAMBLE_SIGNED_TOO_LITTLE; - } - - /* Verify body signature is inside the signed data */ - if (vb2_verify_signature_inside(preamble, sig->data_size, - &preamble->body_signature)) { - VB2_DEBUG("Firmware body signature off end of preamble\n"); - return VB2_ERROR_PREAMBLE_BODY_SIG_OUTSIDE; - } - - /* Verify kernel subkey is inside the signed data */ - if (vb2_verify_packed_key_inside(preamble, sig->data_size, - &preamble->kernel_subkey)) { - VB2_DEBUG("Kernel subkey off end of preamble\n"); - return VB2_ERROR_PREAMBLE_KERNEL_SUBKEY_OUTSIDE; - } - - /* Success */ - return VB2_SUCCESS; -} |