本文分享自华为云社区《华为云短信服务教你用C++实现Smgp协议》，作者：张俭。

引言&协议概述

中国联合网络通信有限公司短消息网关系统接口协议（SGIP）是中国网通为实现短信业务而制定的一种通信协议，全称叫做Short Message Gateway Interface Protocol，用于在短消息网关（SMG）和服务提供商（SP）之间、短消息网关（SMG）和短消息网关（SMG）之间通信。

Perl的IO::Async模块提供了一套简洁的异步IO编程模型。

SGIP 协议基于客户端/服务端模型工作。由客户端（短信应用，如手机，应用程序等）先和短信网关（SMG Short Message Gateway）建立起 TCP 长连接，并使用 SGIP 命令与SMG进行交互，实现短信的发送和接收。在SGIP协议中，无需同步等待响应就可以发送下一个指令，实现者可以根据自己的需要，实现同步、异步两种消息传输模式，满足不同场景下的性能要求。

时序图

连接成功，发送短信

连接成功，从SMGW接收到短信

协议帧介绍

SGIP Header

• Message Length：长度为4字节，整个PDU的长度，包括Header和Body。
• Command ID：长度为4字节，用于标识PDU的类型（例如，Login、Submit等）。
• Sequence Number：长度为8字节，序列号，用来匹配请求和响应。

使用C++实现SMGP协议栈里的建立连接

├── CMakeLists.txt ├── examples │ └── smgp_client_login_example.cpp └── include └── sgipcpp ├── BoundAtomic.h ├── Client.h ├── Protocol.h └── impl ├── BoundAtomic.cpp ├── Client.cpp └── Protocol.cpp

CMakeLists.txt：用来生成Makefile和编译项目

examples：存放示例代码

• smgp_client_login_example.cpp：存放Smgp的login样例

include/sgipcpp：包含所有的C++头文件和实现文件

• BoundAtomic.h：递增工具类，用来生成SequenceId
• Client.h：Smgp定义，负责与Smgp服务进行通信，例如建立连接、发送短信等
• Protocol.h：存放PDU，编解码等
• impl/BoundAtomic.cpp：BoundAtomic类的实现
• impl/Client.cpp：Client类的实现
• impl/Protocol.cpp：Protocol中相关函数的实现

实现SequenceId递增

SequenceId是从1到0x7FFFFFFF的值，使用**BoundAtomic**类实现递增：

头文件

#ifndef BOUNDATOMIC_H #define BOUNDATOMIC_H #include <atomic> #include <cassert> class BoundAtomic { public: BoundAtomic(int min, int max); int next_val(); private: int min_; int max_; std::atomic<int> integer_; }; #endif //BOUNDATOMIC_H

内容

#include "sgipcpp/BoundAtomic.h" BoundAtomic::BoundAtomic(int min, int max) : min_(min), max_(max), integer_(min) { assert(min <= max); } int BoundAtomic::next_val() { int current = integer_.load(); int next; do { next = current >= max_ ? min_ : current + 1; } while (!integer_.compare_exchange_strong(current, next)); return next; }

实现SMGP PDU以及编解码函数

在**Protocol.h**中定义SMGP PDU以及编解码函数：

头文件

#ifndef PROTOCOL_H #define PROTOCOL_H #include <cstdint> #include <vector> constexpr uint32_t SGIP_BIND = 0x00000001; constexpr uint32_t SGIP_BIND_RESP = 0x80000001; constexpr uint32_t SGIP_UNBIND = 0x00000002; constexpr uint32_t SGIP_UNBIND_RESP = 0x80000002; constexpr uint32_t SGIP_SUBMIT = 0x00000003; constexpr uint32_t SGIP_SUBMIT_RESP = 0x80000003; constexpr uint32_t SGIP_DELIVER = 0x00000004; constexpr uint32_t SGIP_DELIVER_RESP = 0x80000004; constexpr uint32_t SGIP_REPORT = 0x00000005; constexpr uint32_t SGIP_REPORT_RESP = 0x80000005; constexpr uint32_t SGIP_ADDSP = 0x00000006; constexpr uint32_t SGIP_ADDSP_RESP = 0x80000006; constexpr uint32_t SGIP_MODIFYSP = 0x00000007; constexpr uint32_t SGIP_MODIFYSP_RESP = 0x80000007; constexpr uint32_t SGIP_DELETESP = 0x00000008; constexpr uint32_t SGIP_DELETESP_RESP = 0x80000008; constexpr uint32_t SGIP_QUERYROUTE = 0x00000009; constexpr uint32_t SGIP_QUERYROUTE_RESP = 0x80000009; constexpr uint32_t SGIP_ADDTELESEG = 0x0000000A; constexpr uint32_t SGIP_ADDTELESEG_RESP = 0x8000000A; constexpr uint32_t SGIP_MODIFYTELESEG = 0x0000000B; constexpr uint32_t SGIP_MODIFYTELESEG_RESP = 0x8000000B; constexpr uint32_t SGIP_DELETETELESEG = 0x0000000C; constexpr uint32_t SGIP_DELETETELESEG_RESP = 0x8000000C; constexpr uint32_t SGIP_ADDSMG = 0x0000000D; constexpr uint32_t SGIP_ADDSMG_RESP = 0x8000000D; constexpr uint32_t SGIP_MODIFYSMG = 0x0000000E; constexpr uint32_t SGIP_MODIFYSMG_RESP = 0x8000000E; constexpr uint32_t SGIP_DELETESMG = 0x0000000F; constexpr uint32_t SGIP_DELETESMG_RESP = 0x8000000F; constexpr uint32_t SGIP_CHECKUSER = 0x00000010; constexpr uint32_t SGIP_CHECKUSER_RESP = 0x80000010; constexpr uint32_t SGIP_USERRPT = 0x00000011; constexpr uint32_t SGIP_USERRPT_RESP = 0x80000011; constexpr uint32_t SGIP_TRACE = 0x00001000; constexpr uint32_t SGIP_TRACE_RESP = 0x80001000; struct Header { uint32_t total_length; uint32_t command_id; uint64_t sequence_number; }; struct Bind { char login_type; char login_name[16]; char login_passwd[16]; char reserve[8]; }; struct BindResp { char result; char reserve[8]; }; struct Pdu { Header header; union { Bind bind; BindResp bind_resp; }; }; size_t lengthBind(); std::vector<uint8_t> encodePdu(const Pdu& pdu); Pdu decodePdu(const std::vector<uint8_t>& buffer); #endif //PROTOCOL_H

内容

#include "sgipcpp/Protocol.h" #include <cstring> #include <ostream> #include <stdexcept> #include <sys/_endian.h> size_t lengthBind(const Bind& bind) { return 1 + 16 + 16 + 8; } void encodeBind(const Bind& bind, std::vector<uint8_t>& buffer) { size_t offset = 16; buffer[offset++] = bind.login_type; std::memcpy(buffer.data() + offset, bind.login_name, 16); offset += 16; std::memcpy(buffer.data() + offset, bind.login_passwd, 16); offset += 16; std::memcpy(buffer.data() + offset, bind.reserve, 8); } BindResp decodeBindResp(const std::vector<uint8_t>& buffer) { BindResp bindResp; size_t offset = 0; offset += sizeof(uint32_t); offset += sizeof(uint32_t); bindResp.result = buffer[offset++]; std::memcpy(bindResp.reserve, buffer.data() + offset, sizeof(bindResp.reserve)); return bindResp; } std::vector<uint8_t> encodePdu(const Pdu& pdu) { size_t body_length; switch (pdu.header.command_id) { case SGIP_BIND: body_length = lengthBind(pdu.bind); break; default: throw std::runtime_error("Unsupported command ID for encoding"); } std::vector<uint8_t> buffer(body_length + 16); uint32_t total_length = htonl(body_length + 16); std::memcpy(buffer.data(), &total_length, 4); uint32_t command_id = htonl(pdu.header.command_id); std::memcpy(buffer.data() + 4, &command_id, 4); uint32_t sequence_number = htonl(pdu.header.sequence_number); std::memcpy(buffer.data() + 8, &sequence_number, 8); switch (pdu.header.command_id) { case SGIP_BIND: encodeBind(pdu.bind, buffer); break; default: throw std::runtime_error("Unsupported command ID for encoding"); } return buffer; } Pdu decodePdu(const std::vector<uint8_t>& buffer) { Pdu pdu; uint32_t command_id; std::memcpy(&command_id, buffer.data(), 4); pdu.header.command_id = ntohl(command_id); uint64_t sequence_number; std::memcpy(&sequence_number, buffer.data() + 8, 8); pdu.header.sequence_number = ntohl(sequence_number); switch (pdu.header.command_id) { case SGIP_BIND_RESP: pdu.bind_resp = decodeBindResp(buffer); break; default: throw std::runtime_error("Unsupported command ID for decoding"); } return pdu; }

实现客户端和登录方法

在**Client**中实现客户端和登录方法：

头文件

#ifndef CLIENT_H #define CLIENT_H #include "BoundAtomic.h" #include "Protocol.h" #include "asio.hpp" #include <string> class Client { public: Client(const std::string& host, uint16_t port); ~Client(); void connect(); BindResp bind(const Bind& bind_request); void close(); private: std::string host_; uint16_t port_; asio::io_context io_context_; asio::ip::tcp::socket socket_; BoundAtomic* sequence_number_; void send(const std::vector<uint8_t>& data); std::vector<uint8_t> receive(size_t length); }; #endif //CLIENT_H

内容

#include "sgipcpp/Client.h" #include <iostream> Client::Client(const std::string& host, uint16_t port) : host_(host), port_(port), socket_(io_context_) { sequence_number_ = new BoundAtomic(1, 0x7FFFFFFF); } Client::~Client() { close(); delete sequence_number_; } void Client::connect() { asio::ip::tcp::resolver resolver(io_context_); asio::connect(socket_, resolver.resolve(host_, std::to_string(port_))); } BindResp Client::bind(const Bind& bind_request) { Pdu pdu; pdu.header.total_length = sizeof(Bind) + sizeof(Header); pdu.header.command_id = SGIP_BIND; pdu.header.sequence_number = sequence_number_->next_val(); pdu.bind = bind_request; send(encodePdu(pdu)); auto length_data = receive(4); uint32_t total_length = ntohl(*reinterpret_cast<uint32_t*>(length_data.data())); auto resp_data = receive(total_length - 4); Pdu resp_pdu = decodePdu(resp_data); return resp_pdu.bind_resp; } void Client::close() { socket_.close(); } void Client::send(const std::vector<uint8_t>& data) { asio::write(socket_, asio::buffer(data)); } std::vector<uint8_t> Client::receive(size_t length) { std::vector<uint8_t> buffer(length); asio::read(socket_, asio::buffer(buffer)); return buffer; }

运行example，验证连接成功

#include "sgipcpp/Client.h" #include <iostream> int main() { try { Client client("127.0.0.1", 8801); client.connect(); std::cout << "Connected to the server." << std::endl; Bind bindRequest; bindRequest.login_type = 1; std::string login_name = "1234567890123456"; std::string login_password = "1234567890123456"; std::string reserve = "12345678"; std::copy(login_name.begin(), login_name.end(), bindRequest.login_name); std::copy(login_password.begin(), login_password.end(), bindRequest.login_passwd); std::copy(reserve.begin(), reserve.end(), bindRequest.reserve); BindResp response = client.bind(bindRequest); if (response.result == 0) { std::cout << "Login successful." << std::endl; } else { std::cout << "Login failed with result code: " << static_cast<int>(response.result) << std::endl; } client.close(); std::cout << "Connection closed." << std::endl; } catch (const std::exception& e) { std::cerr << "Error: " << e.what() << std::endl; } return 0; }

相关开源项目

• netty-codec-sms 存放各种SMS协议（如cmpp、sgip、smpp）的netty编解码器
• sms-client-java 存放各种SMS协议的Java客户端
• sms-server-java 存放各种SMS协议的Java服务端
• cmpp-python cmpp协议的python实现
• cngp-zig cmpp协议的python实现
• sgip-cpp sgip协议的cpp实现
• smgp-perl smgp协议的perl实现
• smpp-rust smpp协议的rust实现

总结

本文简单对SGIP协议进行了介绍，并尝试用C++实现协议栈，但实际商用发送短信往往更加复杂，面临诸如流控、运营商对接、传输层安全等问题，可以选择华为云消息&短信（Message & SMS）服务通过HTTP协议接入，华为云短信服务是华为云携手全球多家优质运营商和渠道，为企业用户提供的通信服务。企业调用API或使用群发助手，即可使用验证码、通知短信服务。

点击关注，第一时间了解华为云新鲜技术~