Suggest net.tcp.service.read

[freak]

Hi,

I'd like to check for the string returned by a tcp connection, i.e. "SSH-1.99-OpenSSH_4.3" to check if sshd is actually running.
Or even the a host's hostkey (i.e. "ssh-rsa AAAAB3Nza...LiPk==").

I'm just wondering whether there is an existing function to use to read and return that answer string.

Maybe someone can point me into a direction.

Thanks
Sebastian

[freak]

Patch net.tcp.service.read (severely needs testing and code review)

I wrote some code to just read the output of a TCP connection - using get_http_page as example..

Again: I'm new to zabbix and I'm new to C, so please be patient and I'd appreciate some comments..

This patch is based on trunk (rev. 4901):

./src/libs/zbxsysinfo/common/net.c

diff --exclude=.svn -Nru trunk/src/libs/zbxsysinfo/common/net.c trunk-new/src/libs/zbxsysinfo/common/net.c
--- trunk/src/libs/zbxsysinfo/common/net.c      2007-10-11 09:42:36.000000000 +0200
+++ trunk-new/src/libs/zbxsysinfo/common/net.c  2007-10-22 14:06:53.000000000 +0200
@@ -259,3 +259,41 @@
        return SYSINFO_RET_FAIL;
 #endif /* not WINDOWS */
 }
+
+/* read from TCP connections */
+int    tcp_read(       const char      *host,          /* hostname or IP to connect to */
+                       unsigned short  port,           /* port to connect to */
+                       const char      *request,       /* request string */
+                       const char      *value_str,     /* value_str holds the result */
+                       int             max_buf_len
+               )
+{
+       zbx_sock_t      s;
+       char    *buf,
+               str_request[MAX_STRING_LEN];
+       int     ret = SYSINFO_RET_FAIL;
+
+       assert(value_str);
+
+       if(SUCCEED == (ret = zbx_tcp_connect(&s,host,port)))
+       {
+               zbx_snprintf(str_request,sizeof(str_request),"%s",request);
+               if(SUCCEED == (ret = zbx_tcp_send_raw(&s,str_request)))
+               {
+                       if(SUCCEED == (ret = zbx_tcp_recv(&s,&buf)))
+                       {
+                               zbx_rtrim(buf,"\n\r\0");
+                               zbx_snprintf((char *) value_str,max_buf_len,"%s",buf);
+                       }
+               }
+       }
+       zbx_tcp_close(&s);
+
+       if(FAIL == ret)
+       {
+               zabbix_log(LOG_LEVEL_DEBUG, "tcp_read error: %s:%s", host, port);
+               return SYSINFO_RET_FAIL;
+       }
+
+       return SYSINFO_RET_OK;
+} 

./src/libs/zbxsysinfo/common/net.h

diff --exclude=.svn -Nru trunk/src/libs/zbxsysinfo/common/net.h trunk-new/src/libs/zbxsysinfo/common/net.h
--- trunk/src/libs/zbxsysinfo/common/net.h      2007-10-11 09:42:36.000000000 +0200
+++ trunk-new/src/libs/zbxsysinfo/common/net.h  2007-10-22 11:00:10.000000000 +0200
@@ -22,6 +22,7 @@
 #include "sysinfo.h"

 int    tcp_expect(const char   *host, unsigned short port, const char *request, const char *expect, const char *sendtoclose, int *value_int);
+int    tcp_read(const char *host, unsigned short port, const char *request, const char *value_str, int max_buf_len);
 int    TCP_LISTEN(const char *cmd, const char *param, unsigned flags, AGENT_RESULT *result);
 int    CHECK_PORT(const char *cmd, const char *param, unsigned flags, AGENT_RESULT *result);
 int    CHECK_DNS(const char *cmd, const char *param, unsigned flags, AGENT_RESULT *result); 

./src/libs/zbxsysinfo/simple/simple.c

diff --exclude=.svn -Nru trunk/src/libs/zbxsysinfo/simple/simple.c trunk-new/src/libs/zbxsysinfo/simple/simple.c
--- trunk/src/libs/zbxsysinfo/simple/simple.c   2007-10-11 09:42:36.000000000 +0200
+++ trunk-new/src/libs/zbxsysinfo/simple/simple.c       2007-10-22 16:41:12.000000000 +0200
@@ -33,6 +33,7 @@
        {
        {"net.tcp.service",     CF_USEUPARAM,   CHECK_SERVICE,          0,      "ssh,127.0.0.1,22"},
        {"net.tcp.service.perf",CF_USEUPARAM,   CHECK_SERVICE_PERF,     0,      "ssh,127.0.0.1,22"},
+       {"net.tcp.service.read",CF_USEUPARAM,   CHECK_SERVICE_READ,     0,      "ssh,127.0.0.1,22"},
        {0}
        };

@@ -398,3 +399,67 @@
        return ret;
 }

+int    CHECK_SERVICE_READ(const char *cmd, const char *param, unsigned flags, AGENT_RESULT *result)
+{
+       unsigned short  port=0;
+       char    service[MAX_STRING_LEN];
+       char    host[MAX_STRING_LEN];
+       char    str_port[MAX_STRING_LEN];
+
+       int     ret = SYSINFO_RET_FAIL;
+       char    value_str[MAX_STRING_LEN]; /* holds the service_read() result */
+
+       assert(result);
+
+       init_result(result);
+
+       /* Parameter Checking and Defaults */
+       if(num_param(param)>3)
+       {
+               return ret;
+       }
+
+       if(get_param(param,1,service,MAX_STRING_LEN)!=0)
+       {
+               return ret;
+       }
+
+       /* no parameter found, set empty */
+       if(get_param(param,2,host,MAX_STRING_LEN)!=0)
+       {
+               host[0]='\0';
+       }
+
+       /* if empty, set default */
+       if(host[0]=='\0')
+       {
+               strscpy(host,"127.0.0.1");
+       }
+
+       if(get_param(param,3,str_port,MAX_STRING_LEN)!=0)
+       {
+               str_port[0]='\0';
+       }
+
+       if(str_port[0]!='\0')
+       {
+               port = atoi(str_port);
+       }
+       else
+       {
+               port = 0;
+       }
+
+       /* Predefined Services */
+       /* SSH */
+       if(strcmp(service,"ssh")==0)
+       {
+               if(port==0)     port=22;
+               tcp_read(host,port,"",(char *) &value_str,255);
+               SET_STR_RESULT(result, strdup(value_str));
+               ret = SYSINFO_RET_OK;
+       }
+
+       return ret;
+}
+ 

./src/libs/zbxsysinfo/simple/simple.h

diff --exclude=.svn -Nru trunk/src/libs/zbxsysinfo/simple/simple.h trunk-new/src/libs/zbxsysinfo/simple/simple.h
--- trunk/src/libs/zbxsysinfo/simple/simple.h   2007-10-11 09:42:36.000000000 +0200
+++ trunk-new/src/libs/zbxsysinfo/simple/simple.h       2007-10-19 17:00:37.000000000 +0200
@@ -23,6 +23,7 @@

 extern ZBX_METRIC      parameters_simple[];

+int    CHECK_SERVICE_READ(const char *cmd, const char *param, unsigned flags, AGENT_RESULT *result);
 int    CHECK_SERVICE_PERF(const char *cmd, const char *param, unsigned flags, AGENT_RESULT *result);
 int    CHECK_SERVICE(const char *cmd, const char *param, unsigned flags, AGENT_RESULT *result); 

Example:
Now

zabbix_agentd -t net.tcp.service.read[ssh,localhost,22]

gives me

net.tcp.service.read[ssh,localhost,22]        [s|SSH-1.99-OpenSSH_4.3]

I was not sure what to use as max_buf_len so I just used 255 when calling

tcp_read(host,port,"",(char *) &value_str,255);

(Using \[PHP\] instead of \[CODE\] for syntax highlighting purposes..)

[tadams]

I would very much like to see this to. I have proxies that the only way to detect they are running properly is to look at returned headers from webpages which are forced through the proxy.

With this functionality, it would allow me to validate that the proxy is online.

[sire]

Please register a feature request here https://support.zabbix.com/secure/Dashboard.jspa, so that Zabbix developers notice this.