changed bash scripts key/cert generation to openssl lib

.gitignore

@@ -8,4 +8,5 @@
 /toolchain/sysroot/
 /toolchain/build/
 
-.vscode/
+.vscode/
+check/

CMakeLists.txt

@@ -37,6 +37,7 @@ set( HEADERS
         src/Services/DeviceControlService.h
         src/Services/EnrollmentService.h
         src/Security/TlsKeyUtil.h
+        src/Security/SslCertUtil.h
 )
 
 add_executable( ${PROJECT_NAME} ${SOURCES} ${HEADERS} )

src/Security/SslCertUtil.h

@@ -0,0 +1,512 @@
+// src/Security/SslCertUtil.h
+#pragma once
+
+#include <string>
+#include <vector>
+#include <filesystem>
+#include <fstream>
+#include <stdexcept>
+
+#include <sys/stat.h> // chmod
+
+#include <openssl/evp.h>
+#include <openssl/ec.h>
+#include <openssl/pem.h>
+#include <openssl/x509v3.h>
+#include <openssl/rand.h>
+#include <openssl/hmac.h>
+
+#include <spdlog/spdlog.h>
+
+namespace snoop
+{
+    namespace device_sec
+    {
+
+        class SslCertUtil
+        {
+        public:
+            // Generates:
+            //   - EC P-256 private key at keyPath (PEM, chmod 600)
+            //   - CSR at csrPath with:
+            //       CN = guid
+            //       subjectAltName = URI:urn:device:<guid>
+            static void GenerateEcKeyAndCsr(const std::string &guid,
+                                            const std::filesystem::path &keyPath,
+                                            const std::filesystem::path &csrPath)
+            {
+                spdlog::info("SslCertUtil: generating EC key + CSR for GUID={}", guid);
+
+                EVP_PKEY *pkey = nullptr;
+                EC_KEY *ec = nullptr;
+
+                try
+                {
+                    // ----- 1) Generate EC key (prime256v1) -----
+                    ec = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
+                    if (!ec)
+                    {
+                        throw std::runtime_error("EC_KEY_new_by_curve_name failed");
+                    }
+                    if (EC_KEY_generate_key(ec) != 1)
+                    {
+                        throw std::runtime_error("EC_KEY_generate_key failed");
+                    }
+
+                    pkey = EVP_PKEY_new();
+                    if (!pkey)
+                    {
+                        throw std::runtime_error("EVP_PKEY_new failed");
+                    }
+                    if (EVP_PKEY_assign_EC_KEY(pkey, ec) != 1)
+                    {
+                        throw std::runtime_error("EVP_PKEY_assign_EC_KEY failed");
+                    }
+                    // pkey now owns ec
+                    ec = nullptr; // prevent double free
+
+                    // ----- 5) Write key + CSR to disk -----
+                    SavePrivateKeyPem(pkey, keyPath);
+                    BuildAndSaveCsr(pkey, guid, csrPath);
+
+                    spdlog::info("SslCertUtil: key written to '{}', csr written to '{}'",
+                                 keyPath.string(), csrPath.string());
+                }
+                catch (...)
+                {
+                    if (pkey)
+                    {
+                        EVP_PKEY_free(pkey);
+                    }
+                    if (ec)
+                    {
+                        EC_KEY_free(ec);
+                    }
+                    throw; // rethrow
+                }
+
+                EVP_PKEY_free(pkey);
+            }
+
+            // CSR from an existing key
+            static void GenerateCsrFromExistingKey(const std::string &guid,
+                                                   const std::filesystem::path &keyPath,
+                                                   const std::filesystem::path &csrPath)
+            {
+                spdlog::info("SslCertUtil: generating CSR from existing key '{}'", keyPath.string());
+
+                FILE *kf = fopen(keyPath.string().c_str(), "rb");
+                if (!kf)
+                {
+                    throw std::runtime_error("GenerateCsrFromExistingKey: cannot open key file: " +
+                                             keyPath.string());
+                }
+
+                EVP_PKEY *pkey = PEM_read_PrivateKey(kf, nullptr, nullptr, nullptr);
+                fclose(kf);
+
+                if (!pkey)
+                {
+                    throw std::runtime_error("GenerateCsrFromExistingKey: PEM_read_PrivateKey failed");
+                }
+
+                try
+                {
+                    BuildAndSaveCsr(pkey, guid, csrPath);
+                }
+                catch (...)
+                {
+                    EVP_PKEY_free(pkey);
+                    throw;
+                }
+
+                EVP_PKEY_free(pkey);
+                spdlog::info("SslCertUtil: CSR written to '{}'", csrPath.string());
+            }
+
+            // Encrypt file with AES-256-CBC + PBKDF2 + salt.
+            //
+            // Equivalent to:
+            //   openssl enc -aes-256-cbc -pbkdf2 -salt -pass pass:<password> -in in -out out
+            //
+            // NOTE: Does NOT shred or delete the input file; caller should do that
+            //       (you’ll still call `shred -u` from EnrollmentService).
+            static void EncryptFileAes256CbcPbkdf2(const std::filesystem::path &inPath,
+                                                   const std::filesystem::path &outPath,
+                                                   const std::string &password)
+            {
+                spdlog::info("SslCertUtil: encrypting '{}' -> '{}' (AES-256-CBC + PBKDF2)",
+                             inPath.string(), outPath.string());
+
+                // ----- 1) Read input file -----
+                std::ifstream fin(inPath, std::ios::binary);
+                if (!fin)
+                {
+                    throw std::runtime_error("EncryptFileAes256CbcPbkdf2: cannot open input file: " +
+                                             inPath.string());
+                }
+                std::vector<unsigned char> plaintext(
+                    (std::istreambuf_iterator<char>(fin)),
+                    std::istreambuf_iterator<char>());
+                fin.close();
+
+                // ----- 2) Prepare salt, key, iv -----
+                unsigned char salt[8];
+                if (RAND_bytes(salt, sizeof(salt)) != 1)
+                {
+                    throw std::runtime_error("EncryptFileAes256CbcPbkdf2: RAND_bytes failed");
+                }
+
+                const EVP_CIPHER *cipher = EVP_aes_256_cbc();
+                const int keyLen = EVP_CIPHER_key_length(cipher);
+                const int ivLen = EVP_CIPHER_iv_length(cipher);
+
+                std::vector<unsigned char> keyiv(keyLen + ivLen);
+
+                const int iterations = 10000; // PBKDF2 rounds
+                if (PKCS5_PBKDF2_HMAC(password.c_str(),
+                                      static_cast<int>(password.size()),
+                                      salt, sizeof(salt),
+                                      iterations,
+                                      EVP_sha256(),
+                                      keyLen + ivLen,
+                                      keyiv.data()) != 1)
+                {
+                    throw std::runtime_error("EncryptFileAes256CbcPbkdf2: PKCS5_PBKDF2_HMAC failed");
+                }
+
+                unsigned char *key = keyiv.data();
+                unsigned char *iv = keyiv.data() + keyLen;
+
+                // ----- 3) Encrypt -----
+                EVP_CIPHER_CTX *ctx = EVP_CIPHER_CTX_new();
+                if (!ctx)
+                {
+                    throw std::runtime_error("EncryptFileAes256CbcPbkdf2: EVP_CIPHER_CTX_new failed");
+                }
+
+                std::vector<unsigned char> ciphertext(plaintext.size() + EVP_CIPHER_block_size(cipher));
+                int outLen1 = 0;
+                int outLen2 = 0;
+
+                if (EVP_EncryptInit_ex(ctx, cipher, nullptr, key, iv) != 1)
+                {
+                    EVP_CIPHER_CTX_free(ctx);
+                    throw std::runtime_error("EncryptFileAes256CbcPbkdf2: EVP_EncryptInit_ex failed");
+                }
+
+                if (EVP_EncryptUpdate(ctx,
+                                      ciphertext.data(), &outLen1,
+                                      plaintext.data(), static_cast<int>(plaintext.size())) != 1)
+                {
+                    EVP_CIPHER_CTX_free(ctx);
+                    throw std::runtime_error("EncryptFileAes256CbcPbkdf2: EVP_EncryptUpdate failed");
+                }
+
+                if (EVP_EncryptFinal_ex(ctx,
+                                        ciphertext.data() + outLen1, &outLen2) != 1)
+                {
+                    EVP_CIPHER_CTX_free(ctx);
+                    throw std::runtime_error("EncryptFileAes256CbcPbkdf2: EVP_EncryptFinal_ex failed");
+                }
+
+                EVP_CIPHER_CTX_free(ctx);
+                ciphertext.resize(outLen1 + outLen2);
+
+                // ----- 4) Write output: [salt][ciphertext] -----
+                std::ofstream fout(outPath, std::ios::binary | std::ios::trunc);
+                if (!fout)
+                {
+                    throw std::runtime_error("EncryptFileAes256CbcPbkdf2: cannot open output file: " +
+                                             outPath.string());
+                }
+
+                // Just raw salt followed by ciphertext
+                fout.write(reinterpret_cast<const char *>(salt), sizeof(salt));
+                fout.write(reinterpret_cast<const char *>(ciphertext.data()),
+                           static_cast<std::streamsize>(ciphertext.size()));
+                fout.close();
+
+                spdlog::info("SslCertUtil: encryption finished, wrote {}", outPath.string());
+            }
+
+            // Compute HMAC-SHA256 and return lowercase hex string.
+            // Equivalent to:
+            //   printf %s "<data>" | openssl dgst -sha256 -hmac "<key>" | awk '{print $2}'
+            static std::string ComputeHmacSha256Hex(const std::string &key,
+                                                    const std::string &data)
+            {
+                unsigned char mac[EVP_MAX_MD_SIZE];
+                unsigned int macLen = 0;
+
+                if (!HMAC(EVP_sha256(),
+                          key.data(), static_cast<int>(key.size()),
+                          reinterpret_cast<const unsigned char *>(data.data()),
+                          data.size(),
+                          mac, &macLen))
+                {
+                    throw std::runtime_error("ComputeHmacSha256Hex: HMAC(EVP_sha256) failed");
+                }
+
+                return ToHexLower(mac, macLen);
+            }
+
+            // Decrypt file with AES-256-CBC + PBKDF2 + salt.
+            // Layout: [8-byte salt][ciphertext]
+            // Password is KEK (hex string from HMAC).
+            static void DecryptFileAes256CbcPbkdf2(const std::filesystem::path &inPath,
+                                                   const std::filesystem::path &outPath,
+                                                   const std::string &password)
+            {
+                spdlog::info("SslCertUtil: decrypting '{}' -> '{}' (AES-256-CBC + PBKDF2)",
+                             inPath.string(), outPath.string());
+
+                // ----- 1) Read input file -----
+                std::ifstream fin(inPath, std::ios::binary);
+                if (!fin)
+                {
+                    throw std::runtime_error("DecryptFileAes256CbcPbkdf2: cannot open input file: " +
+                                             inPath.string());
+                }
+                std::vector<unsigned char> enc(
+                    (std::istreambuf_iterator<char>(fin)),
+                    std::istreambuf_iterator<char>());
+                fin.close();
+
+                if (enc.size() < 8)
+                {
+                    throw std::runtime_error("DecryptFileAes256CbcPbkdf2: encrypted file too small");
+                }
+
+                // First 8 bytes = salt, rest = ciphertext
+                unsigned char salt[8];
+                std::copy(enc.begin(), enc.begin() + 8, salt);
+                std::vector<unsigned char> ciphertext(enc.begin() + 8, enc.end());
+
+                // ----- 2) Derive key/iv -----
+                const EVP_CIPHER *cipher = EVP_aes_256_cbc();
+                const int keyLen = EVP_CIPHER_key_length(cipher);
+                const int ivLen = EVP_CIPHER_iv_length(cipher);
+
+                std::vector<unsigned char> keyiv(keyLen + ivLen);
+
+                const int iterations = 10000;
+                if (PKCS5_PBKDF2_HMAC(password.c_str(),
+                                      static_cast<int>(password.size()),
+                                      salt, sizeof(salt),
+                                      iterations,
+                                      EVP_sha256(),
+                                      keyLen + ivLen,
+                                      keyiv.data()) != 1)
+                {
+                    throw std::runtime_error("DecryptFileAes256CbcPbkdf2: PKCS5_PBKDF2_HMAC failed");
+                }
+
+                unsigned char *key = keyiv.data();
+                unsigned char *iv = keyiv.data() + keyLen;
+
+                // ----- 3) Decrypt -----
+                EVP_CIPHER_CTX *ctx = EVP_CIPHER_CTX_new();
+                if (!ctx)
+                {
+                    throw std::runtime_error("DecryptFileAes256CbcPbkdf2: EVP_CIPHER_CTX_new failed");
+                }
+
+                std::vector<unsigned char> plaintext(ciphertext.size() + EVP_CIPHER_block_size(cipher));
+                int outLen1 = 0;
+                int outLen2 = 0;
+
+                if (EVP_DecryptInit_ex(ctx, cipher, nullptr, key, iv) != 1)
+                {
+                    EVP_CIPHER_CTX_free(ctx);
+                    throw std::runtime_error("DecryptFileAes256CbcPbkdf2: EVP_DecryptInit_ex failed");
+                }
+
+                if (EVP_DecryptUpdate(ctx,
+                                      plaintext.data(), &outLen1,
+                                      ciphertext.data(), static_cast<int>(ciphertext.size())) != 1)
+                {
+                    EVP_CIPHER_CTX_free(ctx);
+                    throw std::runtime_error("DecryptFileAes256CbcPbkdf2: EVP_DecryptUpdate failed");
+                }
+
+                if (EVP_DecryptFinal_ex(ctx,
+                                        plaintext.data() + outLen1, &outLen2) != 1)
+                {
+                    EVP_CIPHER_CTX_free(ctx);
+                    throw std::runtime_error("DecryptFileAes256CbcPbkdf2: EVP_DecryptFinal_ex failed");
+                }
+
+                EVP_CIPHER_CTX_free(ctx);
+                plaintext.resize(outLen1 + outLen2);
+
+                // ----- 4) Write plaintext -----
+                std::filesystem::create_directories(outPath.parent_path());
+                std::ofstream fout(outPath, std::ios::binary | std::ios::trunc);
+                if (!fout)
+                {
+                    throw std::runtime_error("DecryptFileAes256CbcPbkdf2: cannot open output file: " +
+                                             outPath.string());
+                }
+
+                fout.write(reinterpret_cast<const char *>(plaintext.data()),
+                           static_cast<std::streamsize>(plaintext.size()));
+                fout.close();
+
+                spdlog::info("SslCertUtil: decryption finished, wrote {}", outPath.string());
+            }
+
+        private:
+            static void BuildAndSaveCsr(EVP_PKEY *pkey,
+                                        const std::string &guid,
+                                        const std::filesystem::path &csrPath)
+            {
+                X509_REQ *req = X509_REQ_new();
+                if (!req)
+                {
+                    throw std::runtime_error("BuildAndSaveCsr: X509_REQ_new failed");
+                }
+
+                try
+                {
+                    // Subject: CN = GUID
+                    X509_NAME *name = X509_NAME_new();
+                    if (!name)
+                    {
+                        throw std::runtime_error("BuildAndSaveCsr: X509_NAME_new failed");
+                    }
+                    if (X509_NAME_add_entry_by_NID(
+                            name,
+                            NID_commonName,
+                            MBSTRING_ASC,
+                            reinterpret_cast<const unsigned char *>(guid.c_str()),
+                            -1, -1, 0) != 1)
+                    {
+                        X509_NAME_free(name);
+                        throw std::runtime_error("BuildAndSaveCsr: X509_NAME_add_entry_by_NID(CN) failed");
+                    }
+                    if (X509_REQ_set_subject_name(req, name) != 1)
+                    {
+                        X509_NAME_free(name);
+                        throw std::runtime_error("BuildAndSaveCsr: X509_REQ_set_subject_name failed");
+                    }
+                    X509_NAME_free(name);
+
+                    // Public key
+                    if (X509_REQ_set_pubkey(req, pkey) != 1)
+                    {
+                        throw std::runtime_error("BuildAndSaveCsr: X509_REQ_set_pubkey failed");
+                    }
+
+                    // subjectAltName = URI:urn:device:<GUID>
+                    X509V3_CTX ctx;
+                    X509V3_set_ctx_nodb(&ctx);
+                    X509V3_set_ctx(&ctx, nullptr, nullptr, req, nullptr, 0);
+
+                    std::string sanStr = "URI:urn:device:" + guid;
+                    X509_EXTENSION *ext = X509V3_EXT_conf_nid(
+                        nullptr, &ctx, NID_subject_alt_name,
+                        const_cast<char *>(sanStr.c_str()));
+                    if (!ext)
+                    {
+                        throw std::runtime_error("BuildAndSaveCsr: X509V3_EXT_conf_nid(subjectAltName) failed");
+                    }
+
+                    STACK_OF(X509_EXTENSION) *exts = sk_X509_EXTENSION_new_null();
+                    if (!exts)
+                    {
+                        X509_EXTENSION_free(ext);
+                        throw std::runtime_error("BuildAndSaveCsr: sk_X509_EXTENSION_new_null failed");
+                    }
+                    sk_X509_EXTENSION_push(exts, ext);
+                    if (X509_REQ_add_extensions(req, exts) != 1)
+                    {
+                        sk_X509_EXTENSION_pop_free(exts, X509_EXTENSION_free);
+                        throw std::runtime_error("BuildAndSaveCsr: X509_REQ_add_extensions failed");
+                    }
+                    sk_X509_EXTENSION_pop_free(exts, X509_EXTENSION_free);
+
+                    // Sign with SHA-256
+                    if (X509_REQ_sign(req, pkey, EVP_sha256()) <= 0)
+                    {
+                        throw std::runtime_error("BuildAndSaveCsr: X509_REQ_sign failed");
+                    }
+
+                    SaveCsrPem(req, csrPath);
+                }
+                catch (...)
+                {
+                    X509_REQ_free(req);
+                    throw;
+                }
+
+                X509_REQ_free(req);
+            }
+
+            static void SavePrivateKeyPem(EVP_PKEY *pkey, const std::filesystem::path &keyPath)
+            {
+                const auto parent = keyPath.parent_path();
+                if (!parent.empty())
+                {
+                    std::filesystem::create_directories(parent);
+                }
+
+                FILE *f = fopen(keyPath.string().c_str(), "wb");
+                if (!f)
+                {
+                    throw std::runtime_error("SavePrivateKeyPem: fopen failed: " + keyPath.string());
+                }
+
+                if (PEM_write_PrivateKey(f, pkey, nullptr, nullptr, 0, nullptr, nullptr) != 1)
+                {
+                    fclose(f);
+                    throw std::runtime_error("SavePrivateKeyPem: PEM_write_PrivateKey failed");
+                }
+
+                fclose(f);
+
+                // chmod 600
+                ::chmod(keyPath.string().c_str(), 0600);
+            }
+
+            static void SaveCsrPem(X509_REQ *req, const std::filesystem::path &csrPath)
+            {
+                const auto parent = csrPath.parent_path();
+                if (!parent.empty())
+                {
+                    std::filesystem::create_directories(parent);
+                }
+
+                FILE *f = fopen(csrPath.string().c_str(), "wb");
+                if (!f)
+                {
+                    throw std::runtime_error("SaveCsrPem: fopen failed: " + csrPath.string());
+                }
+
+                if (PEM_write_X509_REQ(f, req) != 1)
+                {
+                    fclose(f);
+                    throw std::runtime_error("SaveCsrPem: PEM_write_X509_REQ failed");
+                }
+
+                fclose(f);
+            }
+
+            static std::string ToHexLower(const unsigned char *buf, size_t len)
+            {
+                static const char *hex = "0123456789abcdef";
+                std::string out;
+                out.reserve(len * 2);
+
+                for (size_t i = 0; i < len; ++i)
+                {
+                    unsigned char b = buf[i];
+                    out.push_back(hex[b >> 4]);
+                    out.push_back(hex[b & 0x0F]);
+                }
+                return out;
+            }
+        };
+
+    } // namespace device_sec
+} // namespace snoop

src/Security/TlsKeyUtil.h

@@ -9,6 +9,7 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <spdlog/spdlog.h>
+#include "SslCertUtil.h"
 
 namespace snoop
 {
@@ -119,5 +120,100 @@ namespace snoop
 
             return std::vector<uint8_t>(bytes.begin(), bytes.end());
         }
+
+        static std::string GetCpuSerial()
+        {
+            std::ifstream f("/proc/cpuinfo");
+            if (!f)
+            {
+                spdlog::warn("GetCpuSerial: /proc/cpuinfo not available, using fallback");
+                return std::string(12, '9');
+            }
+
+            std::string line;
+            std::regex re(R"(^\s*Serial\s*:\s*([0-9A-Fa-f]+)\s*$)");
+            while (std::getline(f, line))
+            {
+                std::smatch m;
+                if (std::regex_match(line, m, re) && m.size() == 2)
+                {
+                    auto serial = Trim(m[1].str());
+                    if (!serial.empty())
+                    {
+                        return serial;
+                    }
+                }
+            }
+            spdlog::warn("GetCpuSerial: Serial not found, using fallback");
+            return std::string(12, '9');
+        }
+
+        inline bool IsClientKeyInKernelKeyring()
+        {
+            std::string id = Trim(Exec("keyctl search @s user iot-client-key | tail -n1"));
+            return !id.empty();
+        }
+        
+        // Ensure that iot-client-key exists in kernel keyring.
+        // - If already present: no-op, returns false (nothing loaded).
+        // - If not present: decrypts /etc/iot/keys/device.key.enc using KEK
+        //   derived from (GUID, CPU_SERIAL), padds into keyring, returns true.
+        inline bool EnsureClientKeyInKernelKeyring(const std::string &guid)
+        {
+            if (IsClientKeyInKernelKeyring())
+            {
+                spdlog::info("EnsureClientKeyInKernelKeyring: key already present, nothing to do");
+                return false;
+            }
+
+            const std::filesystem::path encPath = "/etc/iot/keys/device.key.enc";
+            if (!std::filesystem::exists(encPath))
+            {
+                throw std::runtime_error("EnsureClientKeyInKernelKeyring: encrypted key not found at " +
+                                         encPath.string());
+            }
+
+            // Derive KEK = HMAC-SHA256(cpuSerial, key=GUID)
+            const std::string cpuSerial = GetCpuSerial();
+            spdlog::info("EnsureClientKeyInKernelKeyring: CPU_SERIAL = {}", cpuSerial);
+
+            const std::string kek =
+                snoop::device_sec::SslCertUtil::ComputeHmacSha256Hex(guid, cpuSerial);
+
+            if (kek.empty())
+            {
+                throw std::runtime_error("EnsureClientKeyInKernelKeyring: empty KEK");
+            }
+            spdlog::debug("EnsureClientKeyInKernelKeyring: KEK (hex) = {}", kek);
+
+            // Decrypt into tmpfs: /run/iot/device.key
+            const std::filesystem::path runDir = "/run/iot";
+            const std::filesystem::path plainPath = runDir / "device.key";
+            std::filesystem::create_directories(runDir);
+
+            snoop::device_sec::SslCertUtil::DecryptFileAes256CbcPbkdf2(
+                encPath,
+                plainPath,
+                kek);
+
+            if (!std::filesystem::exists(plainPath))
+            {
+                throw std::runtime_error("EnsureClientKeyInKernelKeyring: decrypted key not created");
+            }
+
+            // Load into kernel keyring
+            const std::string cmd = "keyctl padd user iot-client-key @s < " + plainPath.string();
+            spdlog::info("EnsureClientKeyInKernelKeyring: loading key into kernel keyring...");
+            auto out = Exec(cmd);
+            spdlog::debug("keyctl padd output:\n{}", out);
+
+            // Securely erase plaintext
+            const std::string shredCmd = "shred -u " + plainPath.string();
+            spdlog::info("EnsureClientKeyInKernelKeyring: shredding plaintext key with '{}'", shredCmd);
+            auto shredOut = Exec(shredCmd);
+            spdlog::debug("shred output:\n{}", shredOut);
+
+            return true;
+        }
     }
 }

src/Services/EnrollmentService.h

@@ -20,6 +20,8 @@
 #include <openssl/asn1.h>
 
 #include "ConfigService.h"
+#include "Security/SslCertUtil.h"
+#include "Security/TlsKeyUtil.h"
 
 namespace snoop
 {
@@ -125,61 +127,181 @@ namespace snoop
 
             spdlog::info("Starting first-run enrollment...");
 
-            // 1) Run gen_device_csr.sh <GUID>
+            // // 1) Run gen_device_csr.sh <GUID>
-            {
+            // {
-                // Assumes script is in the working dir or in PATH
+            //     // Assumes script is in the working dir or in PATH
-                const std::string cmd = "bash ./gen_device_csr.sh " + guid;
+            //     const std::string cmd = "bash ./gen_device_csr.sh " + guid;
-                spdlog::info("Executing: {}", cmd);
+            //     spdlog::info("Executing: {}", cmd);
-                auto out = Exec(cmd);
+            //     auto out = Exec(cmd);
-                spdlog::debug("gen_device_csr.sh output:\n{}", out);
+            //     spdlog::debug("gen_device_csr.sh output:\n{}", out);
-            }
+            // }
             const std::string keyName = "device_" + guid + ".key";
             const std::string csrName = "device_" + guid + ".csr";
 
-            if (!std::filesystem::exists(keyName) || !std::filesystem::exists(csrName))
+            // if (!std::filesystem::exists(keyName) || !std::filesystem::exists(csrName))
-            {
+            // {
-                throw std::runtime_error("CSR or key was not generated by gen_device_csr.sh");
+            //     throw std::runtime_error("CSR or key was not generated by gen_device_csr.sh");
-            }
+            // }
 
-            // 2) CPU serial (awk '/Serial/ {print $3}' /proc/cpuinfo), if empty -> 9 * 12
+            // 1) Generate key + CSR via OpenSSL (no external script)
+            // {
+            //     spdlog::info("Generating device key + CSR via SslCertUtil");
+            //     snoop::device_sec::SslCertUtil::GenerateEcKeyAndCsr(
+            //         guid,
+            //         std::filesystem::path(keyName),
+            //         std::filesystem::path(csrName));
+            // }
+
+            // if (!std::filesystem::exists(keyName) || !std::filesystem::exists(csrName))
+            // {
+            //     throw std::runtime_error("CSR or key was not generated");
+            // }
+
+            // 1) CPU serial (awk '/Serial/ {print $3}' /proc/cpuinfo), if empty -> 9 * 12
             const std::string cpuSerial = ParseCpuSerial();
             spdlog::info("CPU_SERIAL = {}", cpuSerial);
 
             // 3) KEK = HMAC-SHA256(cpuSerial, key=GUID)  (bash equiv used)
+            // std::string kek;
+            // {
+            //     // careful to avoid trailing newline
+            //     const std::string cmd = "printf %s \"" + cpuSerial + "\""
+            //                                                          " | openssl dgst -sha256 -hmac \"" +
+            //                             guid + "\" | awk '{print $2}'";
+            //     spdlog::info("Deriving KEK with HMAC-SHA256");
+            //     kek = Trim(Exec(cmd));
+            //     if (kek.empty())
+            //         throw std::runtime_error("Failed to derive KEK");
+            //     spdlog::debug("KEK (hex) = {}", kek);
+            // }
+
+            // 2) KEK = HMAC-SHA256(cpuSerial, key=GUID)
             std::string kek;
             {
-                // careful to avoid trailing newline
+                spdlog::info("Deriving KEK with HMAC-SHA256 (OpenSSL API)");
-                const std::string cmd = "printf %s \"" + cpuSerial + "\""
+                kek = snoop::device_sec::SslCertUtil::ComputeHmacSha256Hex(guid, cpuSerial);
-                                                                     " | openssl dgst -sha256 -hmac \"" +
-                                        guid + "\" | awk '{print $2}'";
-                spdlog::info("Deriving KEK with HMAC-SHA256");
-                kek = Trim(Exec(cmd));
                 if (kek.empty())
+                {
                     throw std::runtime_error("Failed to derive KEK");
+                }
                 spdlog::debug("KEK (hex) = {}", kek);
             }
 
-            // 4) Encrypt the private key to /etc/iot/keys/device.key.enc using KEK; shred original
+            // // 4) Encrypt the private key to /etc/iot/keys/device.key.enc using KEK; shred original
+            // {
+            //     std::filesystem::create_directories(keystoreDir);
+            //     const std::string cmd =
+            //         "openssl enc -aes-256-cbc -pbkdf2 -salt "
+            //         "-pass pass:" +
+            //         kek + " "
+            //               "-in " +
+            //         keyName + " "
+            //                   "-out " +
+            //         encKeyPath.string() + " "
+            //                               "&& shred -u " +
+            //         keyName;
+            //     spdlog::info("Encrypting private key and shredding plaintext...");
+            //     auto out = Exec(cmd);
+            //     spdlog::debug("openssl enc output:\n{}", out);
+
+            //     if (!std::filesystem::exists(encKeyPath))
+            //     {
+            //         throw std::runtime_error("Encrypted key not created: " + encKeyPath.string());
+            //     }
+            // }
+
+            // 3) Generate key + CSR via OpenSSL (no external script)
+            if (!std::filesystem::exists(encKeyPath))
             {
+                // ---- Fresh key: generate + encrypt ----
+                spdlog::info("No encrypted key yet -> generating new EC key + CSR");
+                snoop::device_sec::SslCertUtil::GenerateEcKeyAndCsr(
+                    guid,
+                    std::filesystem::path(keyName),
+                    std::filesystem::path(csrName));
+
+                if (!std::filesystem::exists(keyName) || !std::filesystem::exists(csrName))
+                    throw std::runtime_error("CSR or key was not generated");
+
                 std::filesystem::create_directories(keystoreDir);
-                const std::string cmd =
+
-                    "openssl enc -aes-256-cbc -pbkdf2 -salt "
+                spdlog::info("Encrypting private key via SslCertUtil (AES-256-CBC + PBKDF2)...");
-                    "-pass pass:" +
+                snoop::device_sec::SslCertUtil::EncryptFileAes256CbcPbkdf2(
-                    kek + " "
+                    std::filesystem::path(keyName),
-                          "-in " +
+                    encKeyPath,
-                    keyName + " "
+                    kek);
-                              "-out " +
-                    encKeyPath.string() + " "
-                                          "&& shred -u " +
-                    keyName;
-                spdlog::info("Encrypting private key and shredding plaintext...");
-                auto out = Exec(cmd);
-                spdlog::debug("openssl enc output:\n{}", out);
 
                 if (!std::filesystem::exists(encKeyPath))
-                {
                     throw std::runtime_error("Encrypted key not created: " + encKeyPath.string());
+
+                // shred plaintext key
+                const std::string shredCmd = "shred -u " + keyName;
+                spdlog::info("Shredding plaintext private key with '{}'", shredCmd);
+                auto out = Exec(shredCmd);
+                spdlog::debug("shred output:\n{}", out);
+            }
+            else
+            {
+                // ---- Key already exists: reuse it ----
+                spdlog::info("Encrypted key already exists -> reusing key, regenerating CSR only");
+
+                // Decrypt to temp file (in /run/iot)
+                snoop::device_sec::TempFile tf(std::filesystem::path("/run/iot"));
+                snoop::device_sec::SslCertUtil::DecryptFileAes256CbcPbkdf2(
+                    encKeyPath,
+                    tf.path,
+                    kek);
+
+                // Generate CSR from existing key
+                snoop::device_sec::SslCertUtil::GenerateCsrFromExistingKey(
+                    guid,
+                    tf.path,
+                    std::filesystem::path(csrName));
+
+                if (!std::filesystem::exists(csrName))
+                    throw std::runtime_error("CSR was not generated from existing key");
+
+                // TempFile destructor will securely delete the decrypted key file
+            }
+
+            // // 4) Encrypt the private key to /etc/iot/keys/device.key.enc using KEK; shred original
+            // {
+            //     std::filesystem::create_directories(keystoreDir);
+
+            //     spdlog::info("Encrypting private key via SslCertUtil (AES-256-CBC + PBKDF2)...");
+            //     snoop::device_sec::SslCertUtil::EncryptFileAes256CbcPbkdf2(
+            //         std::filesystem::path(keyName),
+            //         encKeyPath,
+            //         kek);
+
+            //     if (!std::filesystem::exists(encKeyPath))
+            //     {
+            //         throw std::runtime_error("Encrypted key not created: " + encKeyPath.string());
+            //     }
+
+            //     // still use shred to securely remove plaintext key, as requested
+            //     const std::string shredCmd = "shred -u " + keyName;
+            //     spdlog::info("Shredding plaintext private key with '{}'", shredCmd);
+            //     auto out = Exec(shredCmd);
+            //     spdlog::debug("shred output:\n{}", out);
+            // }
+
+            // 4.5) Ensure key is loaded into kernel keyring (first creation)
+            try
+            {
+                bool loaded = snoop::device_sec::EnsureClientKeyInKernelKeyring(guid);
+                if (loaded)
+                {
+                    spdlog::info("EnsureEnrolled: client key loaded into kernel keyring");
                 }
+                else
+                {
+                    spdlog::info("EnsureEnrolled: client key was already in keyring");
+                }
+            }
+            catch (const std::exception &e)
+            {
+                spdlog::warn("EnsureEnrolled: failed to load key into keyring: {}", e.what());
             }
 
             // 5) Send CSR to /enroll/:guid as multipart form, field `json: {"csr":"<...>"}`
@@ -287,13 +409,31 @@ namespace snoop
             }
 
             // ----- 2) re-generate CSR via your bash script -----
-            {
+            // {
-                const std::string cmd = "bash ./gen_device_csr.sh " + guid;
+            //     const std::string cmd = "bash ./gen_device_csr.sh " + guid;
-                spdlog::info("Executing (renew): {}", cmd);
+            //     spdlog::info("Executing (renew): {}", cmd);
-                auto out = Exec(cmd);
+            //     auto out = Exec(cmd);
-                spdlog::debug("gen_device_csr.sh (renew) output:\n{}", out);
+            //     spdlog::debug("gen_device_csr.sh (renew) output:\n{}", out);
-            }
+            // }
+            // const std::string csrName = "device_" + guid + ".csr";
+            // if (!std::filesystem::exists(csrName))
+            // {
+            //     throw std::runtime_error("Renew: CSR was not generated");
+            // }
+            // std::string csrPem = ReadFile(csrName);
+
+            // ----- 2) re-generate CSR via OpenSSL (no bash) -----
             const std::string csrName = "device_" + guid + ".csr";
+            {
+                spdlog::info("RenewCertificate: generating new CSR via SslCertUtil");
+                // We must reuse the existing key or generate a new one?
+                // Current flow (bash script) always regenerated key+csr, so we mimic that:
+                snoop::device_sec::SslCertUtil::GenerateEcKeyAndCsr(
+                    guid,
+                    std::filesystem::path("device_" + guid + ".key"),
+                    std::filesystem::path(csrName));
+            }
+
             if (!std::filesystem::exists(csrName))
             {
                 throw std::runtime_error("Renew: CSR was not generated");
@@ -461,7 +601,7 @@ namespace snoop
             if (days == 0 && secs <= 0)
             {
                 return true;
-            }             
+            }
             return days <= daysThreshold;
         }
 

src/main.cpp

@@ -10,6 +10,7 @@
 #include "Services/ConfigService.h"
 #include "Services/EnrollmentService.h"
 #include "Services/DeviceControlService.h"
+#include "Security/TlsKeyUtil.h"
 
 #ifdef USE_ALSA_ADAPTER
 #include "AudioAdapters/AlsaAudioAdapter.h"
@@ -35,22 +36,40 @@ namespace snoop
             auto configService = std::make_shared<ConfigService>("config.json");
 
             // ---- FIRST-RUN ENROLLMENT ----
+            // EnrollmentService enroll(configService);
+            // const bool didEnroll = enroll.EnsureEnrolled();
+            // if (didEnroll)
+            // {
+            //     spdlog::info("First-run enrollment completed.");
+            // }
+            auto enrollSvc = std::make_shared<EnrollmentService>(configService);
+            enrollSvc->EnsureEnrolled();
+            try
             {
-                EnrollmentService enroll(configService);
+                enrollSvc->RenewCertificate(false);
-                const bool didEnroll = enroll.EnsureEnrolled();
+            }
-                if (didEnroll)
+            catch (const std::exception &e)
+            {
+                spdlog::warn("Auto-renew check failed: {}", e.what());
+            }
+
+            // Ensure client key is in kernel keyring for this session
+            try
+            {
+                bool loaded = snoop::device_sec::EnsureClientKeyInKernelKeyring(configService->GetGuid());
+                if (loaded)
                 {
-                    spdlog::info("First-run enrollment completed.");
+                    spdlog::info("Main: client key loaded into kernel keyring for this session");
                 }
-                try
+                else
                 {
-                    enroll.RenewCertificate(false);
+                    spdlog::info("Main: client key already present in kernel keyring");
-                }
-                catch (const std::exception &e)
-                {
-                    spdlog::warn("Auto-renew check failed: {}", e.what());
                 }
             }
+            catch (const std::exception &e)
+            {
+                spdlog::warn("Main: failed to ensure client key in keyring: {}", e.what());
+            }
 
             auto writerService = std::make_shared<AudioWriterService>(configService, "records");