MDEV-8431 Feedback plugin needs an option for http proxy.

'feedback_http_proxy' system variable added to specify the proxy server as host:port. Not a dynamic one.

Author: Alexey Botchkov

plugin/feedback/feedback.cc

@@ -25,7 +25,7 @@ namespace feedback {
 char server_uid_buf[SERVER_UID_SIZE+1]; ///< server uid will be written here
 
 /* backing store for system variables */
-static char *server_uid= server_uid_buf, *url;
+static char *server_uid= server_uid_buf, *url, *http_proxy;
 char *user_info;
 ulong send_timeout, send_retry_wait;
 
@@ -272,7 +272,13 @@ static int init(void *p)
  if (*e == 0 || *e == ' ')
  {
  if (e > s && (urls[slot]= Url::create(s, e - s)))
+ {
+ if (urls[slot]->set_proxy(http_proxy,
+ http_proxy ? strlen(http_proxy) : 0))
+ sql_print_error("feedback plugin: invalid proxy '%s'",
+ http_proxy ? http_proxy : "");
  slot++;
+ }
  else
  {
  if (e > s)
@@ -350,13 +356,18 @@ static MYSQL_SYSVAR_ULONG(send_timeout, send_timeout, PLUGIN_VAR_RQCMDARG,
 static MYSQL_SYSVAR_ULONG(send_retry_wait, send_retry_wait, PLUGIN_VAR_RQCMDARG,
  "Wait this many seconds before retrying a failed send.",
  NULL, NULL, 60, 1, 60*60*24, 1);
+static MYSQL_SYSVAR_STR(http_proxy, http_proxy,
+ PLUGIN_VAR_READONLY | PLUGIN_VAR_RQCMDARG,
+ "Proxy server host:port.", NULL, NULL,0);
+
 
 static struct st_mysql_sys_var* settings[] = {
  MYSQL_SYSVAR(server_uid),
  MYSQL_SYSVAR(user_info),
  MYSQL_SYSVAR(url),
  MYSQL_SYSVAR(send_timeout),
  MYSQL_SYSVAR(send_retry_wait),
+ MYSQL_SYSVAR(http_proxy),
  NULL
 };
 

plugin/feedback/feedback.h

@@ -52,8 +52,14 @@ class Url {
  const char *url() { return full_url.str; }
  size_t url_length() { return full_url.length; }
  virtual int send(const char* data, size_t data_length) = 0;
+ virtual int set_proxy(const char *proxy, size_t proxy_len)
+ {
+ return 0;
+ }
 
  static Url* create(const char *url, size_t url_length);
+ static int parse_proxy_server(const char *proxy_server, size_t proxy_length,
+ LEX_STRING *host, LEX_STRING *port);
 };
 
 extern Url **urls;

plugin/feedback/url_base.cc

@@ -48,4 +48,50 @@ Url* Url::create(const char *url, size_t url_length)
  return self;
 }
 
+
+int Url::parse_proxy_server(const char *proxy_server, size_t proxy_length,
+ LEX_STRING *host, LEX_STRING *port)
+{
+ const char *s;
+
+ host->length= 0;
+ if (proxy_server == NULL)
+ return 0;
+
+ for (; proxy_length > 0 && isspace(*proxy_server);
+ proxy_server++, proxy_length--) /* no-op */;
+
+ if (proxy_length == 0)
+ return 0;
+
+ for (s=proxy_server; *s && *s != ':'; s++) /* no-op */;
+
+ host->str= const_cast<char*>(proxy_server);
+ if ((host->length= s-proxy_server) == 0)
+ return 0;
+
+ port->length= 0;
+
+ if (*s == ':')
+ {
+ s++;
+ port->str= const_cast<char*>(s);
+ while (*s >= '0' && *s <= '9')
+ {
+ s++;
+ port->length++;
+ }
+ }
+
+ if (port->length == 0)
+ {
+ port->str= const_cast<char*>("80");
+ port->length= 2;
+ }
+
+ host->str= my_strndup(host->str, host->length, MYF(MY_WME));
+ port->str= my_strndup(port->str, port->length, MYF(MY_WME));
+ return 0;
+}
+
 } // namespace feedback

plugin/feedback/url_http.cc

@@ -38,20 +38,39 @@ class Url_http: public Url {
  protected:
  const LEX_STRING host, port, path;
  bool ssl;
+ LEX_STRING proxy_host, proxy_port;
+
+ int use_proxy()
+ {
+ return proxy_host.length;
+ }
 
  Url_http(LEX_STRING &url_arg, LEX_STRING &host_arg,
  LEX_STRING &port_arg, LEX_STRING &path_arg, bool ssl_arg) :
  Url(url_arg), host(host_arg), port(port_arg), path(path_arg), ssl(ssl_arg)
- {}
+ {
+ proxy_host.length= 0;
+ }
  ~Url_http()
  {
  my_free(host.str);
  my_free(port.str);
  my_free(path.str);
+ set_proxy(0,0);
  }
 
  public:
  int send(const char* data, size_t data_length);
+ int set_proxy(const char *proxy, size_t proxy_len)
+ {
+ if (use_proxy())
+ {
+ my_free(proxy_host.str);
+ my_free(proxy_port.str);
+ }
+
+ return parse_proxy_server(proxy, proxy_len, &proxy_host, &proxy_port);
+ }
 
  friend Url* http_create(const char *url, size_t url_length);
 };
@@ -150,7 +169,9 @@ int Url_http::send(const char* data, size_t data_length)
  uint len= 0;
 
  addrinfo *addrs, *addr, filter= {0, AF_UNSPEC, SOCK_STREAM, 6, 0, 0, 0, 0};
- int res= getaddrinfo(host.str, port.str, &filter, &addrs);
+ int res= use_proxy() ?
+ getaddrinfo(proxy_host.str, proxy_port.str, &filter, &addrs) :
+ getaddrinfo(host.str, port.str, &filter, &addrs);
 
  if (res)
  {
@@ -228,16 +249,20 @@ int Url_http::send(const char* data, size_t data_length)
  };
 
  len= my_snprintf(buf, sizeof(buf),
- "POST %s HTTP/1.0\r\n"
- "User-Agent: MariaDB User Feedback Plugin\r\n"
- "Host: %s:%s\r\n"
- "Accept: */*\r\n"
- "Content-Length: %u\r\n"
- "Content-Type: multipart/form-data; boundary=%s\r\n"
- "\r\n",
- path.str, host.str, port.str,
- (uint)(2*boundary.length + header.length + data_length + 4),
- boundary.str + 2);
+ use_proxy() ? "POST http://%s:%s/" : "POST ",
+ host.str, port.str);
+
+ len+= my_snprintf(buf+len, sizeof(buf)-len,
+ "%s HTTP/1.0\r\n"
+ "User-Agent: MariaDB User Feedback Plugin\r\n"
+ "Host: %s:%s\r\n"
+ "Accept: */*\r\n"
+ "Content-Length: %u\r\n"
+ "Content-Type: multipart/form-data; boundary=%s\r\n"
+ "\r\n",
+ path.str, host.str, port.str,
+ (uint)(2*boundary.length + header.length + data_length + 4),
+ boundary.str + 2);
 
  vio_timeout(vio, FOR_READING, send_timeout);
  vio_timeout(vio, FOR_WRITING, send_timeout);