diff options
Diffstat (limited to 'src/openvpn/mtu.h')
| -rw-r--r-- | src/openvpn/mtu.h | 122 |
1 files changed, 62 insertions, 60 deletions
diff --git a/src/openvpn/mtu.h b/src/openvpn/mtu.h index 0320545..471e51e 100644 --- a/src/openvpn/mtu.h +++ b/src/openvpn/mtu.h @@ -5,7 +5,7 @@ * packet encryption, packet authentication, and * packet compression. * - * Copyright (C) 2002-2010 OpenVPN Technologies, Inc. <sales@openvpn.net> + * Copyright (C) 2002-2017 OpenVPN Technologies, Inc. <sales@openvpn.net> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 @@ -28,7 +28,7 @@ #include "buffer.h" /* - * + * * Packet maninipulation routes such as encrypt, decrypt, compress, decompress * are passed a frame buffer that looks like this: * @@ -92,20 +92,20 @@ * Packet geometry parameters. */ struct frame { - int link_mtu; /**< Maximum packet size to be sent over + int link_mtu; /**< Maximum packet size to be sent over * the external network interface. */ - int link_mtu_dynamic; /**< Dynamic MTU value for the external + int link_mtu_dynamic; /**< Dynamic MTU value for the external * network interface. */ - int extra_frame; /**< Maximum number of bytes that all + int extra_frame; /**< Maximum number of bytes that all * processing steps together could add. * @code * frame.link_mtu = "socket MTU" - extra_frame; * @endcode */ - int extra_buffer; /**< Maximum number of bytes that + int extra_buffer; /**< Maximum number of bytes that * processing steps could expand the * internal work buffer. * @@ -115,24 +115,24 @@ struct frame { * space for worst-case expansion of * incompressible content. */ - int extra_tun; /**< Maximum number of bytes in excess of + int extra_tun; /**< Maximum number of bytes in excess of * the tun/tap MTU that might be read * from or written to the virtual * tun/tap network interface. */ - int extra_link; /**< Maximum number of bytes in excess of + int extra_link; /**< Maximum number of bytes in excess of * external network interface's MTU that * might be read from or written to it. */ - /* - * Alignment control - */ -# define FRAME_HEADROOM_MARKER_DECRYPT (1<<0) -# define FRAME_HEADROOM_MARKER_FRAGMENT (1<<1) -# define FRAME_HEADROOM_MARKER_READ_LINK (1<<2) -# define FRAME_HEADROOM_MARKER_READ_STREAM (1<<3) - unsigned int align_flags; - int align_adjust; + /* + * Alignment control + */ +#define FRAME_HEADROOM_MARKER_DECRYPT (1<<0) +#define FRAME_HEADROOM_MARKER_FRAGMENT (1<<1) +#define FRAME_HEADROOM_MARKER_READ_LINK (1<<2) +#define FRAME_HEADROOM_MARKER_READ_STREAM (1<<3) + unsigned int align_flags; + int align_adjust; }; /* Forward declarations, to prevent includes */ @@ -198,20 +198,21 @@ struct options; * Function prototypes. */ -void frame_finalize (struct frame *frame, - bool link_mtu_defined, - int link_mtu, - bool tun_mtu_defined, - int tun_mtu); +void frame_finalize(struct frame *frame, + bool link_mtu_defined, + int link_mtu, + bool tun_mtu_defined, + int tun_mtu); + +void frame_subtract_extra(struct frame *frame, const struct frame *src); -void frame_subtract_extra (struct frame *frame, const struct frame *src); +void frame_print(const struct frame *frame, + int level, + const char *prefix); -void frame_print (const struct frame *frame, - int level, - const char *prefix); +void set_mtu_discover_type(int sd, int mtu_type, sa_family_t proto_af); -void set_mtu_discover_type (int sd, int mtu_type, sa_family_t proto_af); -int translate_mtu_discover_type_name (const char *name); +int translate_mtu_discover_type_name(const char *name); /* * frame_set_mtu_dynamic and flags @@ -220,18 +221,18 @@ int translate_mtu_discover_type_name (const char *name); #define SET_MTU_TUN (1<<0) /* use tun/tap rather than link sizing */ #define SET_MTU_UPPER_BOUND (1<<1) /* only decrease dynamic MTU */ -void frame_set_mtu_dynamic (struct frame *frame, int mtu, unsigned int flags); +void frame_set_mtu_dynamic(struct frame *frame, int mtu, unsigned int flags); /* * allocate a buffer for socket or tun layer */ -void alloc_buf_sock_tun (struct buffer *buf, - const struct frame *frame, - const bool tuntap_buffer, - const unsigned int align_mask); +void alloc_buf_sock_tun(struct buffer *buf, + const struct frame *frame, + const bool tuntap_buffer, + const unsigned int align_mask); /** Set the --mssfix option. */ -void frame_init_mssfix (struct frame *frame, const struct options *options); +void frame_init_mssfix(struct frame *frame, const struct options *options); /* * EXTENDED_SOCKET_ERROR_CAPABILITY functions -- print extra error info @@ -241,8 +242,9 @@ void frame_init_mssfix (struct frame *frame, const struct options *options); #if EXTENDED_SOCKET_ERROR_CAPABILITY -void set_sock_extended_error_passing (int sd); -const char *format_extended_socket_error (int fd, int *mtu, struct gc_arena *gc); +void set_sock_extended_error_passing(int sd); + +const char *format_extended_socket_error(int fd, int *mtu, struct gc_arena *gc); #endif @@ -251,12 +253,12 @@ const char *format_extended_socket_error (int fd, int *mtu, struct gc_arena *gc) * headroom and alignment issues. */ static inline int -frame_headroom (const struct frame *f, const unsigned int flag_mask) +frame_headroom(const struct frame *f, const unsigned int flag_mask) { - const int offset = FRAME_HEADROOM_BASE (f); - const int adjust = (flag_mask & f->align_flags) ? f->align_adjust : 0; - const int delta = ((PAYLOAD_ALIGN << 24) - (offset + adjust)) & (PAYLOAD_ALIGN - 1); - return offset + delta; + const int offset = FRAME_HEADROOM_BASE(f); + const int adjust = (flag_mask & f->align_flags) ? f->align_adjust : 0; + const int delta = ((PAYLOAD_ALIGN << 24) - (offset + adjust)) & (PAYLOAD_ALIGN - 1); + return offset + delta; } /* @@ -264,57 +266,57 @@ frame_headroom (const struct frame *f, const unsigned int flag_mask) */ static inline void -frame_add_to_link_mtu (struct frame *frame, const int increment) +frame_add_to_link_mtu(struct frame *frame, const int increment) { - frame->link_mtu += increment; + frame->link_mtu += increment; } static inline void -frame_add_to_extra_frame (struct frame *frame, const int increment) +frame_add_to_extra_frame(struct frame *frame, const int increment) { - frame->extra_frame += increment; + frame->extra_frame += increment; } static inline void -frame_add_to_extra_tun (struct frame *frame, const int increment) +frame_add_to_extra_tun(struct frame *frame, const int increment) { - frame->extra_tun += increment; + frame->extra_tun += increment; } static inline void -frame_add_to_extra_link (struct frame *frame, const int increment) +frame_add_to_extra_link(struct frame *frame, const int increment) { - frame->extra_link += increment; + frame->extra_link += increment; } static inline void -frame_add_to_extra_buffer (struct frame *frame, const int increment) +frame_add_to_extra_buffer(struct frame *frame, const int increment) { - frame->extra_buffer += increment; + frame->extra_buffer += increment; } static inline void -frame_add_to_align_adjust (struct frame *frame, const int increment) +frame_add_to_align_adjust(struct frame *frame, const int increment) { - frame->align_adjust += increment; + frame->align_adjust += increment; } static inline void -frame_align_to_extra_frame (struct frame *frame) +frame_align_to_extra_frame(struct frame *frame) { - frame->align_adjust = frame->extra_frame + frame->extra_link; + frame->align_adjust = frame->extra_frame + frame->extra_link; } static inline void -frame_or_align_flags (struct frame *frame, const unsigned int flag_mask) +frame_or_align_flags(struct frame *frame, const unsigned int flag_mask) { - frame->align_flags |= flag_mask; + frame->align_flags |= flag_mask; } static inline bool -frame_defined (const struct frame *frame) +frame_defined(const struct frame *frame) { - return frame->link_mtu > 0; + return frame->link_mtu > 0; } -#endif +#endif /* ifndef MTU_H */ |