src/vsl_ssh.c File Reference

Functions to perform SSH Starting Mode handshake. More...

#include "vsl_ssh.h"
#include "vsl_util.h"
#include "vsl.h"
#include <sys/types.h>
#include <sys/wait.h>
#include <netdb.h>
#include <sys/select.h>
#include <fcntl.h>

Go to the source code of this file.

Data Structures
struct	ssh_msg_port
	message containing the port More...
struct	ssh_msg_secret
	message containing the secret More...
Functions
int	ssh_close (vsl_sock *sock, char *errmsg)
int	ssh_daemonize (void)
int	ssh_fork (vsl_sock *sock, const char *host, const char *user, const char *cmd, int argc, const char *const *argv)
int	ssh_read_port (vsl_sock *sock, int *port)
int	ssh_read_secret (unsigned char *secret)
int	ssh_send_port (int port)
int	ssh_send_secret (vsl_sock *sock, const unsigned char *secret)
int	ssh_vfer_accept (vsl_sock *sock)
int	ssh_vfer_connect (vsl_sock *sock, const char *host, int port)
int	ssh_vfer_listen (vsl_sock *sock, int *port)

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Detailed Description

Functions to perform SSH Starting Mode handshake.

Author:

Nikolaus Rath

Definition in file vsl_ssh.c.

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Function Documentation

int ssh_close	(	vsl_sock *	sock,
		char *	errmsg
	)

Close ssh process

Parameters:

[in]	sock	socket to use
[out]	errmsg	if the ssh process returned an error message, it is written into this variable, which has to have a minimum length of 513 bytes.

Returns:

• 0 on success
• VFER_INPROGRESS if the socket is nonblocking and the call would block.
• VSL_SSHF if the ssh process failed
• VSL_TEMP if the server signaled a temporary error
• VSL_PERM if the server signaled a permanent error
• VSL_BADPROT in case of a protocol error
• VSL_ERRNO for all other errors (errno is set accordingly)

Todo:

This close call often fails with 'Bad file descriptor!' -- ist that normal behaviour if the program has quit and there's no data on the pipe?

Definition at line 266 of file vsl_ssh.c.

int ssh_daemonize

(

void

)

Daemonizes the process

Returns:

• 0 on success
• VSL_ERRNO if a system call failed (errno is set accordingly)

Definition at line 562 of file vsl_ssh.c.

int ssh_fork	(	vsl_sock *	sock,
		const char *	host,
		const char *	user,
		const char *	cmd,
		int	argc,
		const char *const *	argv
	)

Fork ssh process to connect to remote host and and start server process.

Stores pid and stdin of the ssh process in the socket.

Parameters:

[in]	sock	VSL socket to use
[in]	host	hostname to connect to
[in]	user	username for SSH connection, NULL to use current user
[in]	cmd	program name of the server application
[in]	argc	number of arguments in argv that are passed to the server application
[in]	argv	arguments that is passed to the server application

Returns:

• 0 on success
• VSL_ERRNO for all other errors (errno is set accordingly)

Definition at line 51 of file vsl_ssh.c.

int ssh_read_port	(	vsl_sock *	sock,
		int *	port
	)

Read port number from ssh process

Parameters:

[in]	sock	socket to use
[out]	port	read port

Returns:

• 0 on success
• VFER_INPROGRESS if the socket is nonblocking and the call would block.
• VSL_BADPROT in case of a protocol error
• VSL_ERRNO for all other errors (errno is set accordingly)

Definition at line 220 of file vsl_ssh.c.

int ssh_read_secret

(

unsigned char *

secret

)

Reads the secret from stdin and stores it in the socket.

Parameters:

[out]

secret

variable to store secret in, minimum length VSL_KEYLEN

Returns:

• 0 on success
• VSL_BADPROT in case of a protocol error
• VSL_ERRNO if a system call failed (errno is set accordingly)

Definition at line 414 of file vsl_ssh.c.

int ssh_send_port

(

int

port

)

Prints the given port

Parameters:

[in]

port

port

Returns:

• 0 on success
• VSL_ERRNO if a system call failed (errno is set accordingly)

Definition at line 493 of file vsl_ssh.c.

int ssh_send_secret	(	vsl_sock *	sock,
		const unsigned char *	secret
	)

Sends the secret over the ssh connection.

Parameters:

[in]	sock	socket to use
[in]	secret	secret to send (length VSL_KEYLENGTH)

Returns:

• 0 on success
• VFER_INPROGRESS if the socket is nonblocking and the call would block.
• VSL_ERRNO for all other errors (errno is set accordingly)

Definition at line 167 of file vsl_ssh.c.

int ssh_vfer_accept

(

vsl_sock *

sock

)

Waits for a vfer connection and closes the listening socket.

Parameters:

[in]

sock

socket to use

Returns:

• 0 on success
• VFER_TIMEOUT a timeout occured

Definition at line 531 of file vsl_ssh.c.

int ssh_vfer_connect	(	vsl_sock *	sock,
		const char *	host,
		int	port
	)

Establish a VFER connection to the given host

Parameters:

[in]	sock	VSL socket to use
[in]	host	hostname to connect to
[in]	port	port to connect to

Returns:

• 0 on success
• VSL_ERRNO for all other errors (errno is set accordingly)

Todo:

Disabled, for debbugging we use blocking IO.

Definition at line 349 of file vsl_ssh.c.

int ssh_vfer_listen	(	vsl_sock *	sock,
		int *	port
	)

Configures the socket to listen on a free port and returns that port.

Parameters:

[in]	sock	socket to use
[out]	port	reserved port

Returns:

• 0 on success
• VSL_ERRNO if a system call failed (errno is set accordingly)

Definition at line 456 of file vsl_ssh.c.

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