/*************************************************************************** * nsock_proxy.h -- PRIVATE interface definitions for proxy handling. * * * ***********************IMPORTANT NSOCK LICENSE TERMS*********************** * * * The nsock parallel socket event library is (C) 1999-2013 Insecure.Com * * LLC This library is free software; you may redistribute and/or * * modify it under the terms of the GNU General Public License as * * published by the Free Software Foundation; Version 2. This guarantees * * your right to use, modify, and redistribute this software under certain * * conditions. 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See the GNU * * General Public License v2.0 for more details * * (http://www.gnu.org/licenses/gpl-2.0.html). * * * ***************************************************************************/ /* $Id$ */ #ifndef NSOCK_PROXY_H #define NSOCK_PROXY_H #include "gh_list.h" #if HAVE_NETDB_H #include #endif #include #include /* ------------------- CONSTANTS ------------------- */ enum nsock_proxy_type { PROXY_TYPE_HTTP = 0, PROXY_TYPE_SOCKS4, PROXY_TYPE_SOCKS4A, PROXY_TYPE_COUNT, }; enum nsock_proxy_state { /* Common initial state for all proxy types. */ PROXY_STATE_INITIAL, /* HTTP proxy states. */ PROXY_STATE_HTTP_TCP_CONNECTED, PROXY_STATE_HTTP_TUNNEL_ESTABLISHED, /* SOCKS 4 proxy states. */ PROXY_STATE_SOCKS4_TCP_CONNECTED, PROXY_STATE_SOCKS4_TUNNEL_ESTABLISHED, /* SOCKS 4A proxy states. */ PROXY_STATE_SOCKS4A_TCP_CONNECTED, PROXY_STATE_SOCKS4A_TUNNEL_ESTABLISHED, }; /* ------------------- STRUCTURES ------------------- */ struct uri { char *scheme; char *user; char *pass; char *host; char *path; int port; }; /* Static information about a proxy node in the chain. This is generated by * parsing the proxy specification string given by user. Those structures are * then read-only and stored in the nsock_pool. */ struct proxy_node { const struct proxy_spec *spec; struct sockaddr_storage ss; size_t sslen; unsigned short port; char *nodestr; /* used for log messages */ gh_lnode_t nodeq; }; /* Ordered list of proxy nodes, as specified in the proxy specification string. */ struct proxy_chain { gh_list_t nodes; }; /* IOD-specific context. For each IOD we establish a tunnel through the chain of * proxies. This structure stores all the related information. */ struct proxy_chain_context { const struct proxy_chain *px_chain; /* Nodes iterator in px_chain->nodes */ struct proxy_node *px_current; /* Current node connection state. */ enum nsock_proxy_state px_state; /* Those fields are used to store information about the final target * to reach. */ enum nse_type target_ev_type; struct sockaddr_storage target_ss; size_t target_sslen; unsigned short target_port; nsock_ev_handler target_handler; }; struct proxy_op { int (*node_new)(struct proxy_node **node, const struct uri *uri); void (*node_delete)(struct proxy_node *node); void (*handler)(nsock_pool nspool, nsock_event nsevent, void *udata); }; struct proxy_spec { const char *prefix; enum nsock_proxy_type type; const struct proxy_op *ops; }; /* ------------------- UTIL FUNCTIONS ------------------- */ int proxy_resolve(const char *host, struct sockaddr *addr, size_t *addrlen); static inline struct proxy_node *proxy_ctx_node_next(struct proxy_chain_context *ctx) { gh_lnode_t *next; assert(ctx); assert(ctx->px_current); next = gh_lnode_next(&ctx->px_current->nodeq); if (!next) return NULL; return container_of(next, struct proxy_node, nodeq); } /* ------------------- PROTOTYPES ------------------- */ struct proxy_chain_context *proxy_chain_context_new(nsock_pool nspool); void proxy_chain_context_delete(struct proxy_chain_context *ctx); void nsock_proxy_ev_dispatch(nsock_pool nspool, nsock_event nsevent, void *udata); void forward_event(nsock_pool nspool, nsock_event nse, void *udata); #endif /* NSOCK_PROXY_H */