Merge "fs_mgr: avb should use built-in kernel command line parser"

};

std::unique_ptr<FsManagerAvbVerifier> FsManagerAvbVerifier::Create() {

    std::string cmdline;

    if (!android::base::ReadFileToString("/proc/cmdline", &cmdline)) {

        PERROR << "Failed to read /proc/cmdline";

        return nullptr;

    }

    std::unique_ptr<FsManagerAvbVerifier> avb_verifier(new FsManagerAvbVerifier());

    if (!avb_verifier) {

        LERROR << "Failed to create unique_ptr<FsManagerAvbVerifier>";

        return nullptr;

    }

    std::string digest;

    std::string hash_alg;

    for (const auto& entry : android::base::Split(android::base::Trim(cmdline), " ")) {

        std::vector<std::string> pieces = android::base::Split(entry, "=");

        const std::string& key = pieces[0];

        const std::string& value = pieces[1];

        if (key == "androidboot.vbmeta.hash_alg") {

            hash_alg = value;

        } else if (key == "androidboot.vbmeta.size") {

            if (!android::base::ParseUint(value.c_str(), &avb_verifier->vbmeta_size_)) {

    std::string value;

    if (!fs_mgr_get_boot_config_from_kernel_cmdline("vbmeta.size", &value) ||

        !android::base::ParseUint(value.c_str(), &avb_verifier->vbmeta_size_)) {

        LERROR << "Invalid hash size: " << value.c_str();

        return nullptr;

    }

        } else if (key == "androidboot.vbmeta.digest") {

            digest = value;

        }

    }

    // Reads hash algorithm.

    size_t expected_digest_size = 0;

    std::string hash_alg;

    fs_mgr_get_boot_config_from_kernel_cmdline("vbmeta.hash_alg", &hash_alg);

    if (hash_alg == "sha256") {

        expected_digest_size = SHA256_DIGEST_LENGTH * 2;

        avb_verifier->hash_alg_ = kSHA256;

    }

    // Reads digest.

    std::string digest;

    fs_mgr_get_boot_config_from_kernel_cmdline("vbmeta.digest", &digest);

    if (digest.size() != expected_digest_size) {

        LERROR << "Unexpected digest size: " << digest.size()

               << " (expected: " << expected_digest_size << ")";