initial commit

.vscode/c_cpp_properties.json

@@ -0,0 +1,18 @@
+{
+  "configurations": [
+    {
+      "name": "linux-gcc-x64",
+      "includePath": [
+        "${workspaceFolder}/**"
+      ],
+      "compilerPath": "/usr/bin/gcc",
+      "cStandard": "${default}",
+      "cppStandard": "${default}",
+      "intelliSenseMode": "linux-gcc-x64",
+      "compilerArgs": [
+        ""
+      ]
+    }
+  ],
+  "version": 4
+}

.vscode/launch.json

@@ -0,0 +1,24 @@
+{
+  "version": "0.2.0",
+  "configurations": [
+    {
+      "name": "C/C++ Runner: Debug Session",
+      "type": "cppdbg",
+      "request": "launch",
+      "args": [],
+      "stopAtEntry": false,
+      "externalConsole": false,
+      "cwd": "/home/omer/Desktop/ssh_com",
+      "program": "/home/omer/Desktop/ssh_com/build/Debug/outDebug",
+      "MIMode": "gdb",
+      "miDebuggerPath": "gdb",
+      "setupCommands": [
+        {
+          "description": "Enable pretty-printing for gdb",
+          "text": "-enable-pretty-printing",
+          "ignoreFailures": true
+        }
+      ]
+    }
+  ]
+}

.vscode/settings.json

@@ -0,0 +1,36 @@
+{
+  "C_Cpp_Runner.cCompilerPath": "gcc",
+  "C_Cpp_Runner.cppCompilerPath": "g++",
+  "C_Cpp_Runner.debuggerPath": "gdb",
+  "C_Cpp_Runner.cStandard": "",
+  "C_Cpp_Runner.cppStandard": "",
+  "C_Cpp_Runner.msvcBatchPath": "C:/Program Files/Microsoft Visual Studio/VR_NR/Community/VC/Auxiliary/Build/vcvarsall.bat",
+  "C_Cpp_Runner.useMsvc": false,
+  "C_Cpp_Runner.warnings": [
+    "-Wall",
+    "-Wextra",
+    "-Wpedantic",
+    "-Wshadow",
+    "-Wformat=2",
+    "-Wconversion",
+    "-Wnull-dereference",
+    "-Wsign-conversion"
+  ],
+  "C_Cpp_Runner.enableWarnings": true,
+  "C_Cpp_Runner.warningsAsError": false,
+  "C_Cpp_Runner.compilerArgs": [],
+  "C_Cpp_Runner.linkerArgs": [],
+  "C_Cpp_Runner.includePaths": [],
+  "C_Cpp_Runner.includeSearch": [
+    "*",
+    "**/*"
+  ],
+  "C_Cpp_Runner.excludeSearch": [
+    "**/build",
+    "**/build/**",
+    "**/.*",
+    "**/.*/**",
+    "**/.vscode",
+    "**/.vscode/**"
+  ]
+}

main.c

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+#include <stdio.h>
+#include <stdlib.h>
+
+
+#include "ssh_com.h"
+
+int main(){
+
+    ssh_session session;
+
+    int port = 22;
+    // char password[] = "2004";
+    char command[] = "iwconfig wlp1s0 | grep Signal | \
+        /usr/bin/awk '{print $4}' | /usr/bin/cut -d'=' -f2";
+
+    // char host[] = "192.168.20.246";
+    // char user[] = "ems";
+
+    FILE *fp;
+    char value;
+
+    initSession(&session, port, "ems", "192.168.20.246", "2004");
+
+    while(1){
+
+    int rssi_value = -getCommandOutputFromChannel(session, command); //this function gives rssi value as positive
+
+    }
+    return 0;
+}

ssh_com.c

@@ -0,0 +1,109 @@
+#include "ssh_com.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <libssh/libssh.h>
+
+void initSession(ssh_session* session, int port, const char* user, 
+                const char* host, const char* password){
+    int rc;
+    printf("new session\n");
+    *session = ssh_new();
+    if(*session == NULL) exit(-1);
+
+    ssh_options_set(*session, SSH_OPTIONS_HOST, host);
+    ssh_options_set(*session, SSH_OPTIONS_PORT, &port);
+    ssh_options_set(*session, SSH_OPTIONS_USER, user); 
+
+    printf("connecting to session..\n");
+    rc = ssh_connect(*session);
+    if(rc != SSH_OK) errorSession(*session);
+
+    printf("Password Autentication...\n");
+    rc = ssh_userauth_password(*session, NULL, password);
+    if(rc != SSH_AUTH_SUCCESS) {
+        fprintf(stderr, "Error authenticating with password: %s\n",
+                ssh_get_error(*session));
+        freeSession(*session);
+        exit(-1);
+    }
+}
+
+void sendCommandToChannel(ssh_session session, ssh_channel *channel, const char* command){
+    int rc;
+    printf("\nChannel...\n");
+    *channel = ssh_channel_new(session);
+    if (*channel == NULL) exit(-1);
+
+    printf("Opening...\n");
+    rc = ssh_channel_open_session(*channel);
+    if(rc != SSH_OK) errorSession(session);
+
+    printf("Executing remote command...\n");
+    rc = ssh_channel_request_exec(*channel, command);
+    if(rc != SSH_OK) errorSession(session);
+}
+
+int getCommandOutputFromChannel(ssh_session session, const char* command){
+    ssh_channel channel;
+    char buffer[1024];
+    unsigned int nbytes;
+
+    FILE *fp;
+    char c;
+    int16_t value;
+    int output[4];
+
+    sendCommandToChannel(session, &channel, command);
+
+    printf("Received:\n");
+    nbytes = ssh_channel_read(channel, buffer, sizeof(buffer), 0);
+    while(nbytes > 0) {
+        fp = fopen("ssh_command_log.txt", "wb");
+        if(fp == NULL) {
+            printf("Error opening file\n");
+            return -1;
+        }
+        if(fwrite(buffer, sizeof(char), nbytes, fp) != nbytes){
+            freeChannel(channel);
+            return SSH_ERROR;
+        }
+        fclose(fp);
+
+        fp = fopen("ssh_command_log.txt", "rb");
+        if (fp == NULL) {
+            printf("Error opening file\n");
+            return -1;
+        }
+        int i = 0;
+        while(1) {
+            c = fgetc(fp);
+            if(feof(fp))break;
+            output[i] = c - 48; //48 is decimal value of char '0' in ASCII
+            printf("%d \t", c - '0'); //value - '0'  is exactly the line above
+            i++;
+        }
+        fclose(fp);
+        nbytes = ssh_channel_read(channel, buffer, sizeof(buffer), 0);
+    }
+    value = ((output[1])*10) + output[2];
+
+    freeChannel(channel);
+    return value;
+}
+
+void errorSession(ssh_session session){
+    fprintf(stderr, "Error: %s\n", ssh_get_error(session));
+    freeSession(session);
+    exit(-1);
+}
+
+void freeSession(ssh_session session){
+    ssh_disconnect(session);
+    ssh_free(session);
+}
+
+void freeChannel(ssh_channel channel){
+    ssh_channel_send_eof(channel);
+    ssh_channel_close(channel);
+    ssh_channel_free(channel);
+}

ssh_com.h

@@ -0,0 +1,17 @@
+#ifndef _SSH_COM_
+#define _SSH_COM_
+
+
+#include <libssh/libssh.h>
+
+void initSession(ssh_session *session, int port, const char* user, 
+                const char* host, const char* password);
+void sendCommandToChannel(ssh_session session, ssh_channel *channel, const char* command);
+int getCommandOutputFromChannel(ssh_session session, const char* command);    
+
+void errorSession(ssh_session session);
+void freeSession(ssh_session session);
+void freeChannel(ssh_channel channel);
+
+
+#endif

ssh_loop.c

@@ -0,0 +1,102 @@
+#include <libssh/libssh.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+void free_channel(ssh_channel channel) {
+    ssh_channel_send_eof(channel);
+    ssh_channel_close(channel);
+    ssh_channel_free(channel);
+}
+
+void free_session(ssh_session session) {
+    ssh_disconnect(session);
+    ssh_free(session);
+}
+
+void error(ssh_session session) {
+    fprintf(stderr, "Error: %s\n", ssh_get_error(session));
+    free_session(session);
+    exit(-1);
+}
+
+int main() {
+
+    ssh_session session;
+    ssh_channel channel;
+    int rc, port = 22;
+    char buffer[1024];
+    unsigned int nbytes;
+
+    char host[] = "192.168.20.246";
+    char user[] = "ems";
+
+    FILE *fp;
+    int c;
+
+    printf("Session...\n");
+    session = ssh_new();
+    if (session == NULL) exit(-1);
+
+    ssh_options_set(session, SSH_OPTIONS_HOST, host);
+    ssh_options_set(session, SSH_OPTIONS_PORT, &port);
+    ssh_options_set(session, SSH_OPTIONS_USER, user);
+
+    printf("Connecting...\n");
+    rc = ssh_connect(session);
+    if (rc != SSH_OK) error(session);
+
+    printf("Password Autentication...\n");
+    rc = ssh_userauth_password(session, NULL, "2004");
+    if (rc != SSH_AUTH_SUCCESS) error(session);
+
+    while (1)
+    {
+        printf("Channel...\n");
+        channel = ssh_channel_new(session);
+        if (channel == NULL) exit(-1);
+
+        printf("Opening...\n");
+        rc = ssh_channel_open_session(channel);
+        if (rc != SSH_OK) error(session);
+
+        printf("Executing remote command...\n");
+        rc = ssh_channel_request_exec(channel, "iwconfig wlp1s0 | grep Signal | /usr/bin/awk '{print $4}' | /usr/bin/cut -d'=' -f2");
+        if (rc != SSH_OK) error(session);
+
+        printf("Received:\n");
+        nbytes = ssh_channel_read(channel, buffer, sizeof(buffer), 0);
+        while (nbytes > 0) {
+            fp = fopen("rssi.txt", "wb");
+            if(fp == NULL) {
+                printf("Error opening file\n");
+                exit(1);
+            }
+            if (fwrite(buffer, sizeof(char), nbytes, fp) != nbytes) {   
+                free_channel(channel);
+                return SSH_ERROR;
+            }
+
+            fclose(fp);
+            fp = fopen("rssi.txt","rb");
+            while(1) {
+                c = fgetc(fp);
+                if( feof(fp) ) {
+                    break ;
+                }
+                printf("%c", c);
+            }
+            fclose(fp);
+            nbytes = ssh_channel_read(channel, buffer, sizeof(buffer), 0);
+        }
+
+        free_channel(channel);
+        usleep(1000000);
+
+    }
+
+    free_channel(channel);
+    free_session(session);
+
+    return 0;
+}