view list.h @ 1790:42745af83b7d

Introduce extra delay before closing unauthenticated sessions To make it harder for attackers, introduce a delay to keep an unauthenticated session open a bit longer, thus blocking a connection slot until after the delay. Without this, while there is a limit on the amount of attempts an attacker can make at the same time (MAX_UNAUTH_PER_IP), the time taken by dropbear to handle one attempt is still short and thus for each of the allowed parallel attempts many attempts can be chained one after the other. The attempt rate is then: "MAX_UNAUTH_PER_IP / <process time of one attempt>". With the delay, this rate becomes: "MAX_UNAUTH_PER_IP / UNAUTH_CLOSE_DELAY".
author Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
date Wed, 15 Feb 2017 13:53:04 +0100
parents 9169e4e7cbee
children
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#ifndef DROPBEAR_DROPBEAR_LIST_H
#define DROPBEAR_DROPBEAR_LIST_H

struct _m_list;

struct _m_list_elem {
	void *item;
	struct _m_list_elem *next;
	struct _m_list_elem *prev;
	struct _m_list *list;
};
	
typedef struct _m_list_elem m_list_elem;

struct _m_list {
	m_list_elem *first;
	m_list_elem *last;
};

typedef struct _m_list m_list;

m_list * list_new(void);
void list_append(m_list *list, void *item);
/* returns the item for the element removed */
void * list_remove(m_list_elem *elem);


#endif /* DROPBEAR_DROPBEAR_LIST_H */