diff options
Diffstat (limited to 'src/openvpn/mtu.c')
| -rw-r--r-- | src/openvpn/mtu.c | 411 |
1 files changed, 220 insertions, 191 deletions
diff --git a/src/openvpn/mtu.c b/src/openvpn/mtu.c index 8cbaa86..73eab21 100644 --- a/src/openvpn/mtu.c +++ b/src/openvpn/mtu.c @@ -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 @@ -41,76 +41,78 @@ /* 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) +alloc_buf_sock_tun(struct buffer *buf, + const struct frame *frame, + const bool tuntap_buffer, + const unsigned int align_mask) { - /* allocate buffer for overlapped I/O */ - *buf = alloc_buf (BUF_SIZE (frame)); - ASSERT (buf_init (buf, FRAME_HEADROOM_ADJ (frame, align_mask))); - buf->len = tuntap_buffer ? MAX_RW_SIZE_TUN (frame) : MAX_RW_SIZE_LINK (frame); - ASSERT (buf_safe (buf, 0)); + /* allocate buffer for overlapped I/O */ + *buf = alloc_buf(BUF_SIZE(frame)); + ASSERT(buf_init(buf, FRAME_HEADROOM_ADJ(frame, align_mask))); + buf->len = tuntap_buffer ? MAX_RW_SIZE_TUN(frame) : MAX_RW_SIZE_LINK(frame); + ASSERT(buf_safe(buf, 0)); } void -frame_finalize (struct frame *frame, - bool link_mtu_defined, - int link_mtu, - bool tun_mtu_defined, - int tun_mtu) +frame_finalize(struct frame *frame, + bool link_mtu_defined, + int link_mtu, + bool tun_mtu_defined, + int tun_mtu) { - /* Set link_mtu based on command line options */ - if (tun_mtu_defined) + /* Set link_mtu based on command line options */ + if (tun_mtu_defined) { - ASSERT (!link_mtu_defined); - frame->link_mtu = tun_mtu + TUN_LINK_DELTA (frame); + ASSERT(!link_mtu_defined); + frame->link_mtu = tun_mtu + TUN_LINK_DELTA(frame); } - else + else { - ASSERT (link_mtu_defined); - frame->link_mtu = link_mtu; + ASSERT(link_mtu_defined); + frame->link_mtu = link_mtu; } - if (TUN_MTU_SIZE (frame) < TUN_MTU_MIN) + if (TUN_MTU_SIZE(frame) < TUN_MTU_MIN) { - msg (M_WARN, "TUN MTU value (%d) must be at least %d", TUN_MTU_SIZE (frame), TUN_MTU_MIN); - frame_print (frame, M_FATAL, "MTU is too small"); + msg(M_WARN, "TUN MTU value (%d) must be at least %d", TUN_MTU_SIZE(frame), TUN_MTU_MIN); + frame_print(frame, M_FATAL, "MTU is too small"); } - frame->link_mtu_dynamic = frame->link_mtu; + frame->link_mtu_dynamic = frame->link_mtu; } /* * Set the tun MTU dynamically. */ void -frame_set_mtu_dynamic (struct frame *frame, int mtu, unsigned int flags) +frame_set_mtu_dynamic(struct frame *frame, int mtu, unsigned int flags) { #ifdef ENABLE_DEBUG - const int orig_mtu = mtu; - const int orig_link_mtu_dynamic = frame->link_mtu_dynamic; + const int orig_mtu = mtu; + const int orig_link_mtu_dynamic = frame->link_mtu_dynamic; #endif - ASSERT (mtu >= 0); + ASSERT(mtu >= 0); - if (flags & SET_MTU_TUN) - mtu += TUN_LINK_DELTA (frame); + if (flags & SET_MTU_TUN) + { + mtu += TUN_LINK_DELTA(frame); + } - if (!(flags & SET_MTU_UPPER_BOUND) || mtu < frame->link_mtu_dynamic) + if (!(flags & SET_MTU_UPPER_BOUND) || mtu < frame->link_mtu_dynamic) { - frame->link_mtu_dynamic = constrain_int ( - mtu, - EXPANDED_SIZE_MIN (frame), - EXPANDED_SIZE (frame)); + frame->link_mtu_dynamic = constrain_int( + mtu, + EXPANDED_SIZE_MIN(frame), + EXPANDED_SIZE(frame)); } - dmsg (D_MTU_DEBUG, "MTU DYNAMIC mtu=%d, flags=%u, %d -> %d", - orig_mtu, - flags, - orig_link_mtu_dynamic, - frame->link_mtu_dynamic); + dmsg(D_MTU_DEBUG, "MTU DYNAMIC mtu=%d, flags=%u, %d -> %d", + orig_mtu, + flags, + orig_link_mtu_dynamic, + frame->link_mtu_dynamic); } /* @@ -119,200 +121,227 @@ frame_set_mtu_dynamic (struct frame *frame, int mtu, unsigned int flags) * queue. */ void -frame_subtract_extra (struct frame *frame, const struct frame *src) +frame_subtract_extra(struct frame *frame, const struct frame *src) { - frame->extra_frame -= src->extra_frame; - frame->extra_tun += src->extra_frame; + frame->extra_frame -= src->extra_frame; + frame->extra_tun += src->extra_frame; } void -frame_init_mssfix (struct frame *frame, const struct options *options) +frame_init_mssfix(struct frame *frame, const struct options *options) { - if (options->ce.mssfix) + if (options->ce.mssfix) { - frame_set_mtu_dynamic (frame, options->ce.mssfix, SET_MTU_UPPER_BOUND); + frame_set_mtu_dynamic(frame, options->ce.mssfix, SET_MTU_UPPER_BOUND); } } void -frame_print (const struct frame *frame, - int level, - const char *prefix) +frame_print(const struct frame *frame, + int level, + const char *prefix) { - struct gc_arena gc = gc_new (); - struct buffer out = alloc_buf_gc (256, &gc); - if (prefix) - buf_printf (&out, "%s ", prefix); - buf_printf (&out, "["); - buf_printf (&out, " L:%d", frame->link_mtu); - buf_printf (&out, " D:%d", frame->link_mtu_dynamic); - buf_printf (&out, " EF:%d", frame->extra_frame); - buf_printf (&out, " EB:%d", frame->extra_buffer); - buf_printf (&out, " ET:%d", frame->extra_tun); - buf_printf (&out, " EL:%d", frame->extra_link); - if (frame->align_flags && frame->align_adjust) - buf_printf (&out, " AF:%u/%d", frame->align_flags, frame->align_adjust); - buf_printf (&out, " ]"); - - msg (level, "%s", out.data); - gc_free (&gc); + struct gc_arena gc = gc_new(); + struct buffer out = alloc_buf_gc(256, &gc); + if (prefix) + { + buf_printf(&out, "%s ", prefix); + } + buf_printf(&out, "["); + buf_printf(&out, " L:%d", frame->link_mtu); + buf_printf(&out, " D:%d", frame->link_mtu_dynamic); + buf_printf(&out, " EF:%d", frame->extra_frame); + buf_printf(&out, " EB:%d", frame->extra_buffer); + buf_printf(&out, " ET:%d", frame->extra_tun); + buf_printf(&out, " EL:%d", frame->extra_link); + if (frame->align_flags && frame->align_adjust) + { + buf_printf(&out, " AF:%u/%d", frame->align_flags, frame->align_adjust); + } + buf_printf(&out, " ]"); + + msg(level, "%s", out.data); + gc_free(&gc); } #define MTUDISC_NOT_SUPPORTED_MSG "--mtu-disc is not supported on this OS" void -set_mtu_discover_type (int sd, int mtu_type, sa_family_t proto_af) +set_mtu_discover_type(int sd, int mtu_type, sa_family_t proto_af) { - if (mtu_type >= 0) + if (mtu_type >= 0) { - switch (proto_af) - { + switch (proto_af) + { #if defined(HAVE_SETSOCKOPT) && defined(IP_MTU_DISCOVER) - case AF_INET: - if (setsockopt - (sd, IPPROTO_IP, IP_MTU_DISCOVER, &mtu_type, sizeof (mtu_type))) - msg (M_ERR, "Error setting IP_MTU_DISCOVER type=%d on TCP/UDP socket", - mtu_type); - break; + case AF_INET: + if (setsockopt + (sd, IPPROTO_IP, IP_MTU_DISCOVER, &mtu_type, sizeof(mtu_type))) + { + msg(M_ERR, "Error setting IP_MTU_DISCOVER type=%d on TCP/UDP socket", + mtu_type); + } + break; + #endif #if defined(HAVE_SETSOCKOPT) && defined(IPV6_MTU_DISCOVER) - case AF_INET6: - if (setsockopt - (sd, IPPROTO_IPV6, IPV6_MTU_DISCOVER, &mtu_type, sizeof (mtu_type))) - msg (M_ERR, "Error setting IPV6_MTU_DISCOVER type=%d on TCP6/UDP6 socket", - mtu_type); - break; + case AF_INET6: + if (setsockopt + (sd, IPPROTO_IPV6, IPV6_MTU_DISCOVER, &mtu_type, sizeof(mtu_type))) + { + msg(M_ERR, "Error setting IPV6_MTU_DISCOVER type=%d on TCP6/UDP6 socket", + mtu_type); + } + break; + #endif - default: - msg (M_FATAL, MTUDISC_NOT_SUPPORTED_MSG); - break; - } + default: + msg(M_FATAL, MTUDISC_NOT_SUPPORTED_MSG); + break; + } } } int -translate_mtu_discover_type_name (const char *name) +translate_mtu_discover_type_name(const char *name) { #if defined(IP_PMTUDISC_DONT) && defined(IP_PMTUDISC_WANT) && defined(IP_PMTUDISC_DO) - if (!strcmp (name, "yes")) - return IP_PMTUDISC_DO; - if (!strcmp (name, "maybe")) - return IP_PMTUDISC_WANT; - if (!strcmp (name, "no")) - return IP_PMTUDISC_DONT; - msg (M_FATAL, - "invalid --mtu-disc type: '%s' -- valid types are 'yes', 'maybe', or 'no'", - name); -#else - msg (M_FATAL, MTUDISC_NOT_SUPPORTED_MSG); + if (!strcmp(name, "yes")) + { + return IP_PMTUDISC_DO; + } + if (!strcmp(name, "maybe")) + { + return IP_PMTUDISC_WANT; + } + if (!strcmp(name, "no")) + { + return IP_PMTUDISC_DONT; + } + msg(M_FATAL, + "invalid --mtu-disc type: '%s' -- valid types are 'yes', 'maybe', or 'no'", + name); +#else /* if defined(IP_PMTUDISC_DONT) && defined(IP_PMTUDISC_WANT) && defined(IP_PMTUDISC_DO) */ + msg(M_FATAL, MTUDISC_NOT_SUPPORTED_MSG); #endif - return -1; /* NOTREACHED */ + return -1; /* NOTREACHED */ } #if EXTENDED_SOCKET_ERROR_CAPABILITY struct probehdr { - uint32_t ttl; - struct timeval tv; + uint32_t ttl; + struct timeval tv; }; const char * -format_extended_socket_error (int fd, int *mtu, struct gc_arena *gc) +format_extended_socket_error(int fd, int *mtu, struct gc_arena *gc) { - int res; - struct probehdr rcvbuf; - struct iovec iov; - struct msghdr msg; - struct cmsghdr *cmsg; - struct sock_extended_err *e; - struct sockaddr_in addr; - struct buffer out = alloc_buf_gc (256, gc); - char *cbuf = (char *) gc_malloc (256, false, gc); - - *mtu = 0; - - while (true) + int res; + struct probehdr rcvbuf; + struct iovec iov; + struct msghdr msg; + struct cmsghdr *cmsg; + struct sock_extended_err *e; + struct sockaddr_in addr; + struct buffer out = alloc_buf_gc(256, gc); + char *cbuf = (char *) gc_malloc(256, false, gc); + + *mtu = 0; + + while (true) { - memset (&rcvbuf, -1, sizeof (rcvbuf)); - iov.iov_base = &rcvbuf; - iov.iov_len = sizeof (rcvbuf); - msg.msg_name = (uint8_t *) &addr; - msg.msg_namelen = sizeof (addr); - msg.msg_iov = &iov; - msg.msg_iovlen = 1; - msg.msg_flags = 0; - msg.msg_control = cbuf; - msg.msg_controllen = 256; /* size of cbuf */ - - res = recvmsg (fd, &msg, MSG_ERRQUEUE); - if (res < 0) - goto exit; - - e = NULL; - - for (cmsg = CMSG_FIRSTHDR (&msg); cmsg; cmsg = CMSG_NXTHDR (&msg, cmsg)) - { - if (cmsg->cmsg_level == SOL_IP) - { - if (cmsg->cmsg_type == IP_RECVERR) - { - e = (struct sock_extended_err *) CMSG_DATA (cmsg); - } - else - { - buf_printf (&out ,"CMSG=%d|", cmsg->cmsg_type); - } - } - } - if (e == NULL) - { - buf_printf (&out, "NO-INFO|"); - goto exit; - } - - switch (e->ee_errno) - { - case ETIMEDOUT: - buf_printf (&out, "ETIMEDOUT|"); - break; - case EMSGSIZE: - buf_printf (&out, "EMSGSIZE Path-MTU=%d|", e->ee_info); - *mtu = e->ee_info; - break; - case ECONNREFUSED: - buf_printf (&out, "ECONNREFUSED|"); - break; - case EPROTO: - buf_printf (&out, "EPROTO|"); - break; - case EHOSTUNREACH: - buf_printf (&out, "EHOSTUNREACH|"); - break; - case ENETUNREACH: - buf_printf (&out, "ENETUNREACH|"); - break; - case EACCES: - buf_printf (&out, "EACCES|"); - break; - default: - buf_printf (&out, "UNKNOWN|"); - break; - } + memset(&rcvbuf, -1, sizeof(rcvbuf)); + iov.iov_base = &rcvbuf; + iov.iov_len = sizeof(rcvbuf); + msg.msg_name = (uint8_t *) &addr; + msg.msg_namelen = sizeof(addr); + msg.msg_iov = &iov; + msg.msg_iovlen = 1; + msg.msg_flags = 0; + msg.msg_control = cbuf; + msg.msg_controllen = 256; /* size of cbuf */ + + res = recvmsg(fd, &msg, MSG_ERRQUEUE); + if (res < 0) + { + goto exit; + } + + e = NULL; + + for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) + { + if (cmsg->cmsg_level == SOL_IP) + { + if (cmsg->cmsg_type == IP_RECVERR) + { + e = (struct sock_extended_err *) CMSG_DATA(cmsg); + } + else + { + buf_printf(&out,"CMSG=%d|", cmsg->cmsg_type); + } + } + } + if (e == NULL) + { + buf_printf(&out, "NO-INFO|"); + goto exit; + } + + switch (e->ee_errno) + { + case ETIMEDOUT: + buf_printf(&out, "ETIMEDOUT|"); + break; + + case EMSGSIZE: + buf_printf(&out, "EMSGSIZE Path-MTU=%d|", e->ee_info); + *mtu = e->ee_info; + break; + + case ECONNREFUSED: + buf_printf(&out, "ECONNREFUSED|"); + break; + + case EPROTO: + buf_printf(&out, "EPROTO|"); + break; + + case EHOSTUNREACH: + buf_printf(&out, "EHOSTUNREACH|"); + break; + + case ENETUNREACH: + buf_printf(&out, "ENETUNREACH|"); + break; + + case EACCES: + buf_printf(&out, "EACCES|"); + break; + + default: + buf_printf(&out, "UNKNOWN|"); + break; + } } - exit: - buf_rmtail (&out, '|'); - return BSTR (&out); +exit: + buf_rmtail(&out, '|'); + return BSTR(&out); } void -set_sock_extended_error_passing (int sd) +set_sock_extended_error_passing(int sd) { - int on = 1; - if (setsockopt (sd, SOL_IP, IP_RECVERR, (void *) &on, sizeof (on))) - msg (M_WARN | M_ERRNO, - "Note: enable extended error passing on TCP/UDP socket failed (IP_RECVERR)"); + int on = 1; + if (setsockopt(sd, SOL_IP, IP_RECVERR, (void *) &on, sizeof(on))) + { + msg(M_WARN | M_ERRNO, + "Note: enable extended error passing on TCP/UDP socket failed (IP_RECVERR)"); + } } -#endif +#endif /* if EXTENDED_SOCKET_ERROR_CAPABILITY */ |