feat: add optional support for TLS trusted_ca_keys extension

lib/staging/tls/CMakeLists.txt

@@ -5,6 +5,8 @@ find_package(OpenSSL 3)
 
 target_sources(tls
     PRIVATE
+        extensions/status_request.cpp
+        extensions/trusted_ca_keys.cpp
         openssl_conv.cpp
         openssl_util.cpp
         tls.cpp

lib/staging/tls/extensions/helpers.cpp

@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright 2024 Pionix GmbH and Contributors to EVerest
+
+#include "helpers.hpp"
+#include "trusted_ca_keys.hpp"
+#include <cstddef>
+
+std::ostream& operator<<(std::ostream& out, const openssl::certificate_ptr& obj) {
+    const auto subject = openssl::certificate_subject(obj.get());
+    if (!subject.empty()) {
+        out << "subject:";
+        for (const auto& itt : subject) {
+            out << " " << itt.first << ":" << itt.second;
+        }
+    }
+    return out;
+}
+
+std::ostream& operator<<(std::ostream& out, const openssl::sha_1_digest_t& obj) {
+    const auto sav = out.flags();
+    for (const auto& c : obj) {
+        out << std::setw(2) << std::setfill('0') << std::hex << static_cast<std::uint32_t>(c);
+    }
+    out.flags(sav);
+    return out;
+}
+
+std::ostream& operator<<(std::ostream& out, const tls::trusted_ca_keys::trusted_ca_keys_t& obj) {
+    out << "trusted ca keys: pre-agreed: " << obj.pre_agreed << std::endl;
+    if (!obj.cert_sha1_hash.empty()) {
+        for (const auto& hash : obj.cert_sha1_hash) {
+            out << "  certificate hash:          " << hash << std::endl;
+        }
+    }
+    if (!obj.key_sha1_hash.empty()) {
+        for (const auto& hash : obj.key_sha1_hash) {
+            out << "  subject key hash:          " << hash << std::endl;
+        }
+    }
+    return out;
+}
+
+std::ostream& operator<<(std::ostream& out, const openssl::DER& obj) {
+    const auto sav = out.flags();
+    const auto* ptr = obj.get();
+    for (std::size_t i = 0; i < obj.size(); i++) {
+        out << std::setw(2) << std::setfill('0') << std::hex << static_cast<std::uint32_t>(*ptr++);
+    }
+    out.flags(sav);
+    return out;
+}

lib/staging/tls/extensions/helpers.hpp

@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright 2024 Pionix GmbH and Contributors to EVerest
+
+#ifndef EXTENSIONS_HELPERS_
+#define EXTENSIONS_HELPERS_
+
+#include <cstdint>
+#include <cstring>
+#include <iomanip>
+#include <sstream>
+#include <string>
+
+#ifdef UNIT_TEST
+#include <iostream>
+#endif
+
+#include <openssl_util.hpp>
+
+namespace tls {
+
+using openssl::log_warning;
+
+/**
+ * \brief update position and remaining by amount
+ * \param[inout] ptr the pointer to increment
+ * \param[inout] remaining the value to decrement
+ */
+constexpr void update_position(const std::uint8_t*& ptr, std::int32_t& remaining, std::size_t amount) {
+    ptr += amount;
+    remaining -= amount;
+}
+
+/**
+ * \brief update position and remaining by amount
+ * \param[inout] ptr the pointer to increment
+ * \param[inout] remaining the value to decrement
+ */
+constexpr void update_position(std::uint8_t*& ptr, std::int32_t& remaining, std::size_t amount) {
+    ptr += amount;
+    remaining -= amount;
+}
+
+/**
+ * \brief copy structure from data pointer
+ * \param[out] dest the destination structure
+ * \param[inout] ptr the pointer the start of the data, updated to point to the
+ *               next byte (ptr += sizeof(dest))
+ * \param[inout] remaining updated with the remaining number of bytes
+ *               (remaining -= sizeof(dest))
+ * \param[in] err_message to log on error
+ * \return true when structure populated from data
+ */
+template <typename T>
+constexpr bool struct_copy(T& dest, const std::uint8_t*& ptr, std::int32_t& remaining, const std::string& err_message) {
+    bool bResult{false};
+    if (remaining < sizeof(T)) {
+        log_warning(err_message);
+    } else {
+        std::memcpy(&dest, ptr, sizeof(T));
+        update_position(ptr, remaining, sizeof(T));
+        bResult = true;
+    }
+    return bResult;
+}
+
+/**
+ * \brief copy structure to data pointer
+ * \param[out] ptr the destination pointer, updated to point to the
+ *             next byte (ptr += sizeof(src))
+ * \param[inout] src the source structure
+ * \param[inout] remaining updated with the remaining number of bytes
+ *               (remaining -= sizeof(src))
+ * \param[in] err_message to log on error
+ * \return true when ptr populated from structure
+ */
+template <typename T>
+constexpr bool struct_copy(std::uint8_t*& ptr, const T& src, std::int32_t& remaining, const std::string& err_message) {
+    bool bResult{false};
+    if (remaining < sizeof(T)) {
+        log_warning(err_message);
+    } else {
+        std::memcpy(ptr, &src, sizeof(T));
+        update_position(ptr, remaining, sizeof(T));
+        bResult = true;
+    }
+    return bResult;
+}
+
+/**
+ * \brief copy DER to data pointer
+ * \param[out] ptr the destination pointer, updated to point to the
+ *             next byte (ptr += src.size())
+ * \param[inout] src the DER source object
+ * \param[inout] remaining updated with the remaining number of bytes
+ *               (remaining -= src.size())
+ * \param[in] err_message to log on error
+ * \return true when ptr populated from structure
+ */
+inline bool der_copy(std::uint8_t*& ptr, const openssl::DER& src, std::int32_t& remaining,
+                     const std::string& err_message) {
+    bool bResult{false};
+    if (remaining < src.size()) {
+        log_warning(err_message + ' ' + std::to_string(remaining) + '/' + std::to_string(src.size()));
+    } else {
+        std::memcpy(ptr, src.get(), src.size());
+        update_position(ptr, remaining, src.size());
+        bResult = true;
+    }
+    return bResult;
+}
+
+/**
+ * \brief convert a big endian 3 byte (24 bit) unsigned value to uint32
+ * \param[in] ptr the pointer to the most significant byte
+ * \return the interpreted value
+ */
+constexpr std::uint32_t uint24(const std::uint8_t* ptr) {
+    return (static_cast<std::uint32_t>(ptr[0]) << 16U) | (static_cast<std::uint32_t>(ptr[1]) << 8U) |
+           static_cast<std::uint32_t>(ptr[2]);
+}
+
+/**
+ * \brief convert a uint32 to big endian 3 byte (24 bit) value
+ * \param[in] ptr the pointer to the most significant byte
+ * \param[in] value the 24 bit value
+ */
+constexpr void uint24(std::uint8_t* ptr, std::uint32_t value) {
+    ptr[0] = (value >> 16U) & 0xffU;
+    ptr[1] = (value >> 8U) & 0xffU;
+    ptr[2] = value & 0xffU;
+}
+
+/**
+ * \brief convert a big endian 2 byte (16 bit) unsigned value to uint16
+ * \param[in] ptr the pointer to the most significant byte
+ * \return the interpreted value
+ */
+constexpr std::uint16_t uint16(const std::uint8_t* ptr) {
+    return (static_cast<std::uint32_t>(ptr[0]) << 8U) | static_cast<std::uint32_t>(ptr[1]);
+}
+
+/**
+ * \brief convert a uint16 to big endian 2 byte (16 bit) value
+ * \param[in] ptr the pointer to the most significant byte
+ * \param[in] value the 16 bit value
+ */
+constexpr void uint16(std::uint8_t* ptr, std::uint32_t value) {
+    ptr[0] = (value >> 8U) & 0xffU;
+    ptr[1] = value & 0xffU;
+}
+
+template <typename T> std::string to_string(const T& digest) {
+    std::stringstream string_stream;
+    string_stream << std::hex;
+    for (const auto& c : digest) {
+        string_stream << std::setw(2) << std::setfill('0') << static_cast<int>(c);
+    }
+    return string_stream.str();
+}
+
+} // namespace tls
+
+#ifdef UNIT_TEST
+namespace tls::trusted_ca_keys {
+struct trusted_ca_keys_t;
+}
+
+std::ostream& operator<<(std::ostream& out, const openssl::certificate_ptr& obj);
+std::ostream& operator<<(std::ostream& out, const openssl::sha_1_digest_t& obj);
+std::ostream& operator<<(std::ostream& out, const tls::trusted_ca_keys::trusted_ca_keys_t& obj);
+std::ostream& operator<<(std::ostream& out, const openssl::DER& obj);
+#endif
+
+#endif // EXTENSIONS_HELPERS_