/*   * Sample showing how to do SFTP transfers.   *   * The sample code has default values for host name, user name, password   * and path to copy, but you can specify them on the command line like:   *   * "sftp 192.168.0.1 user password /tmp/secrets -p|-i|-k"   */      #include "libssh2_config.h"  #include <libssh2.h>  #include <libssh2_sftp.h>      #ifdef HAVE_WINSOCK2_H  #include <winsock2.h>  #endif  #ifdef HAVE_SYS_SOCKET_H  #include <sys/socket.h>  #endif  #ifdef HAVE_NETINET_IN_H  #include <netinet/in.h>  #endif  #ifdef HAVE_UNISTD_H  #include <unistd.h>  #endif  #ifdef HAVE_ARPA_INET_H  #include <arpa/inet.h>  #endif  #ifdef HAVE_SYS_TIME_H  #include <sys/time.h>  #endif      #include <sys/types.h>  #include <fcntl.h>  #include <errno.h>  #include <stdio.h>  #include <ctype.h>          const char *keyfile1="~/.ssh/id_rsa.pub";  const char *keyfile2="~/.ssh/id_rsa";  const char *username="username";  const char *password="password";  const char *sftppath="/tmp/TEST";          static void kbd_callback(const char *name, int name_len,               const char *instruction, int instruction_len, int num_prompts,               const LIBSSH2_USERAUTH_KBDINT_PROMPT *prompts,               LIBSSH2_USERAUTH_KBDINT_RESPONSE *responses,               void **abstract)  {      int i;      size_t n;      char buf[1024];      (void)abstract;          printf("Performing keyboard-interactive authentication.\n");          printf("Authentication name: '");      fwrite(name, 1, name_len, stdout);      printf("'\n");          printf("Authentication instruction: '");      fwrite(instruction, 1, instruction_len, stdout);      printf("'\n");          printf("Number of prompts: %d\n\n", num_prompts);          for (i = 0; i < num_prompts; i++) {          printf("Prompt %d from server: '", i);          fwrite(prompts[i].text, 1, prompts[i].length, stdout);          printf("'\n");              printf("Please type response: ");          fgets(buf, sizeof(buf), stdin);          n = strlen(buf);          while (n > 0 && strchr("\r\n", buf[n - 1]))            n--;          buf[n] = 0;              responses[i].text = strdup(buf);          responses[i].length = n;              printf("Response %d from user is '", i);          fwrite(responses[i].text, 1, responses[i].length, stdout);          printf("'\n\n");      }          printf("Done. Sending keyboard-interactive responses to server now.\n");  }          int main(int argc, char *argv[])  {      unsigned long hostaddr;      int sock, i, auth_pw = 0;      struct sockaddr_in sin;      const char *fingerprint;      char *userauthlist;      LIBSSH2_SESSION *session;      int rc;      LIBSSH2_SFTP *sftp_session;      LIBSSH2_SFTP_HANDLE *sftp_handle;      #ifdef WIN32      WSADATA wsadata;          WSAStartup(MAKEWORD(2,0), &wsadata);  #endif          if (argc > 1) {          hostaddr = inet_addr(argv[1]);      } else {          hostaddr = htonl(0x7F000001);      }          if(argc > 2) {          username = argv[2];      }      if(argc > 3) {          password = argv[3];      }      if(argc > 4) {          sftppath = argv[4];      }          rc = libssh2_init (0);         if (rc != 0) {          fprintf (stderr, "libssh2 initialization failed (%d)\n", rc);          return 1;      }          /*       * The application code is responsible for creating the socket       * and establishing the connection       */      sock = socket(AF_INET, SOCK_STREAM, 0);          sin.sin_family = AF_INET;      sin.sin_port = htons(22);      sin.sin_addr.s_addr = hostaddr;      if (connect(sock, (struct sockaddr*)(&sin),                  sizeof(struct sockaddr_in)) != 0) {          fprintf(stderr, "failed to connect!\n");          return -1;      }          /* Create a session instance       */      session = libssh2_session_init();         if(!session)          return -1;          /* Since we have set non-blocking, tell libssh2 we are blocking */      libssh2_session_set_blocking(session, 1);             /* ... start it up. This will trade welcome banners, exchange keys,       * and setup crypto, compression, and MAC layers       */      rc = libssh2_session_handshake(session, sock);         if(rc) {          fprintf(stderr, "Failure establishing SSH session: %d\n", rc);          return -1;      }          /* At this point we havn't yet authenticated.  The first thing to do       * is check the hostkey's fingerprint against our known hosts Your app       * may have it hard coded, may go to a file, may present it to the       * user, that's your call       */      fingerprint = libssh2_hostkey_hash(session, LIBSSH2_HOSTKEY_HASH_SHA1);         fprintf(stderr, "Fingerprint: ");      for(i = 0; i < 20; i++) {          fprintf(stderr, "%02X ", (unsigned char)fingerprint[i]);      }      fprintf(stderr, "\n");          /* check what authentication methods are available */      userauthlist = libssh2_userauth_list(session, username, strlen(username));         printf("Authentication methods: %s\n", userauthlist);      if (strstr(userauthlist, "password") != NULL) {          auth_pw |= 1;      }      if (strstr(userauthlist, "keyboard-interactive") != NULL) {          auth_pw |= 2;      }      if (strstr(userauthlist, "publickey") != NULL) {          auth_pw |= 4;      }          /* if we got an 4. argument we set this option if supported */      if(argc > 5) {          if ((auth_pw & 1) && !strcasecmp(argv[5], "-p")) {              auth_pw = 1;          }          if ((auth_pw & 2) && !strcasecmp(argv[5], "-i")) {              auth_pw = 2;          }          if ((auth_pw & 4) && !strcasecmp(argv[5], "-k")) {              auth_pw = 4;          }      }          if (auth_pw & 1) {          /* We could authenticate via password */          if (libssh2_userauth_password(session, username, password)) {                 fprintf(stderr, "Authentication by password failed.\n");              goto shutdown;          }      } else if (auth_pw & 2) {          /* Or via keyboard-interactive */          if (libssh2_userauth_keyboard_interactive(session, username, &kbd_callback) ) {                 printf("\tAuthentication by keyboard-interactive failed!\n");              goto shutdown;          } else {              printf("\tAuthentication by keyboard-interactive succeeded.\n");          }      } else if (auth_pw & 4) {          /* Or by public key */          if (libssh2_userauth_publickey_fromfile(session, username, keyfile1, keyfile2, password)) {                 printf("\tAuthentication by public key failed!\n");              goto shutdown;          } else {              printf("\tAuthentication by public key succeeded.\n");          }      } else {          printf("No supported authentication methods found!\n");          goto shutdown;      }          fprintf(stderr, "libssh2_sftp_init()!\n");         sftp_session = libssh2_sftp_init(session);             if (!sftp_session) {          fprintf(stderr, "Unable to init SFTP session\n");          goto shutdown;      }          fprintf(stderr, "libssh2_sftp_open()!\n");         /* Request a file via SFTP */      sftp_handle =          libssh2_sftp_open(sftp_session, sftppath, LIBSSH2_FXF_READ, 0);             if (!sftp_handle) {          fprintf(stderr, "Unable to open file with SFTP: %ld\n",                  libssh2_sftp_last_error(sftp_session));             goto shutdown;      }      fprintf(stderr, "libssh2_sftp_open() is done, now receive data!\n");         do {          char mem[1024];              /* loop until we fail */          fprintf(stderr, "libssh2_sftp_read()!\n");             rc = libssh2_sftp_read(sftp_handle, mem, sizeof(mem));             if (rc > 0) {              write(1, mem, rc);          } else {              break;          }      } while (1);          libssh2_sftp_close(sftp_handle);         libssh2_sftp_shutdown(sftp_session);           shutdown:          libssh2_session_disconnect(session, "Normal Shutdown, Thank you for playing");         libssh2_session_free(session);         #ifdef WIN32      closesocket(sock);  #else      close(sock);  #endif      fprintf(stderr, "all done\n");          libssh2_exit();             return 0;  }