From bf55e9931ce203049385fbf55dde291ead556679 Mon Sep 17 00:00:00 2001 From: Neale Ranns Date: Thu, 4 Oct 2018 06:40:30 -0700 Subject: mss_clamp: TCP MSS clamping plugin Type: feature Configure TCP MSS clamping on an interface as follows: set interface tcp-mss-clamp [rx|tx] ip4 [enable|disable|rx|tx] ip4-mss ip6 [enable|disable|rx|tx] ip6-mss Change-Id: I45b04e50a0b70a33e14a9066f981c651292ebffb Signed-off-by: Neale Ranns Signed-off-by: Paul Vinciguerra Signed-off-by: Miklos Tirpak Signed-off-by: Matthew Smith --- src/plugins/mss_clamp/mss_clamp.c | 292 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 292 insertions(+) create mode 100644 src/plugins/mss_clamp/mss_clamp.c (limited to 'src/plugins/mss_clamp/mss_clamp.c') diff --git a/src/plugins/mss_clamp/mss_clamp.c b/src/plugins/mss_clamp/mss_clamp.c new file mode 100644 index 00000000000..cdac5456641 --- /dev/null +++ b/src/plugins/mss_clamp/mss_clamp.c @@ -0,0 +1,292 @@ +/* + * mss_clamp.c - TCP MSS clamping plug-in + * + * Copyright (c) 2018 Cisco and/or its affiliates + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include +#include +#include +#include + +mssc_main_t mssc_main; + +/* Action function shared between message handler and debug CLI */ + +static void +mssc_enable_disable_feat (u32 sw_if_index, u8 dir4, u8 dir6, int enable) +{ + if (dir4 == MSS_CLAMP_DIR_NONE && dir6 == MSS_CLAMP_DIR_NONE) + return; + + // ip4 + if ((dir4 & MSS_CLAMP_DIR_RX) != MSS_CLAMP_DIR_NONE) + vnet_feature_enable_disable ("ip4-unicast", "tcp-mss-clamping-ip4-in", + sw_if_index, enable, 0, 0); + if ((dir4 & MSS_CLAMP_DIR_TX) != MSS_CLAMP_DIR_NONE) + vnet_feature_enable_disable ("ip4-output", "tcp-mss-clamping-ip4-out", + sw_if_index, enable, 0, 0); + // ip6 + if ((dir6 & MSS_CLAMP_DIR_RX) != MSS_CLAMP_DIR_NONE) + vnet_feature_enable_disable ("ip6-unicast", "tcp-mss-clamping-ip6-in", + sw_if_index, enable, 0, 0); + if ((dir6 & MSS_CLAMP_DIR_TX) != MSS_CLAMP_DIR_NONE) + vnet_feature_enable_disable ("ip6-output", "tcp-mss-clamping-ip6-out", + sw_if_index, enable, 0, 0); +} + +int +mssc_enable_disable (u32 sw_if_index, u8 dir4, u8 dir6, u16 mss4, u16 mss6) +{ + mssc_main_t *cm = &mssc_main; + u8 *dir_enabled4, *dir_enabled6; + int rv = 0; + + if (dir4 == MSS_CLAMP_DIR_NONE) + mss4 = MSS_CLAMP_UNSET; + if (dir6 == MSS_CLAMP_DIR_NONE) + mss6 = MSS_CLAMP_UNSET; + + vec_validate_init_empty (cm->dir_enabled4, sw_if_index, MSS_CLAMP_DIR_NONE); + vec_validate_init_empty (cm->dir_enabled6, sw_if_index, MSS_CLAMP_DIR_NONE); + vec_validate_init_empty (cm->max_mss4, sw_if_index, MSS_CLAMP_UNSET); + vec_validate_init_empty (cm->max_mss6, sw_if_index, MSS_CLAMP_UNSET); + + cm->max_mss4[sw_if_index] = mss4; + cm->max_mss6[sw_if_index] = mss6; + dir_enabled4 = &cm->dir_enabled4[sw_if_index]; + dir_enabled6 = &cm->dir_enabled6[sw_if_index]; + + // Disable the directions that are no longer needed + mssc_enable_disable_feat (sw_if_index, (*dir_enabled4) & ~dir4, + (*dir_enabled6) & ~dir6, 0); + // Enable the new directions + mssc_enable_disable_feat (sw_if_index, ~(*dir_enabled4) & dir4, + ~(*dir_enabled6) & dir6, 1); + + *dir_enabled4 = dir4; + *dir_enabled6 = dir6; + + return rv; +} + +int +mssc_get_mss (u32 sw_if_index, u8 *dir4, u8 *dir6, u16 *mss4, u16 *mss6) +{ + mssc_main_t *cm = &mssc_main; + int rv = VNET_API_ERROR_FEATURE_DISABLED; + + if (vec_len (cm->dir_enabled4) > sw_if_index && + MSS_CLAMP_DIR_NONE != cm->dir_enabled4[sw_if_index]) + { + *mss4 = cm->max_mss4[sw_if_index]; + *dir4 = cm->dir_enabled4[sw_if_index]; + rv = 0; + } + else + { + *mss4 = MSS_CLAMP_DIR_NONE; + *dir4 = 0; + } + + if (vec_len (cm->dir_enabled6) > sw_if_index && + MSS_CLAMP_DIR_NONE != cm->dir_enabled6[sw_if_index]) + { + *mss6 = cm->max_mss6[sw_if_index]; + *dir6 = cm->dir_enabled6[sw_if_index]; + rv = 0; + } + else + { + *mss6 = MSS_CLAMP_DIR_NONE; + *dir6 = 0; + } + return rv; +} + +static uword +unformat_mssc_dir (unformat_input_t *input, va_list *args) +{ + u8 *result = va_arg (*args, u8 *); + u8 dir = MSS_CLAMP_DIR_RX | MSS_CLAMP_DIR_TX; + + if (unformat (input, "disable")) + dir = MSS_CLAMP_DIR_NONE; + else if (unformat (input, "enable")) + dir = MSS_CLAMP_DIR_RX | MSS_CLAMP_DIR_TX; + else if (unformat (input, "rx")) + dir = MSS_CLAMP_DIR_RX; + else if (unformat (input, "tx")) + dir = MSS_CLAMP_DIR_TX; + else + return 0; + + *result = dir; + return 1; +} + +static clib_error_t * +mssc_enable_command_fn (vlib_main_t *vm, unformat_input_t *input, + vlib_cli_command_t *cmd) +{ + u32 sw_if_index = ~0; + u8 dir4 = ~0, dir6 = ~0; + u32 mss4 = ~0, mss6 = ~0; + int rv; + + while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT) + { + if (unformat (input, "ip4 %U", unformat_mssc_dir, &dir4)) + ; + else if (unformat (input, "ip6 %U", unformat_mssc_dir, &dir6)) + ; + else if (unformat (input, "ip4-mss %d", &mss4)) + ; + else if (unformat (input, "ip6-mss %d", &mss6)) + ; + else if (unformat (input, "%U", unformat_vnet_sw_interface, + vnet_get_main (), &sw_if_index)) + ; + else + break; + } + + if (sw_if_index == ~0) + return clib_error_return (0, "Please specify an interface"); + + if (dir4 == (u8) ~0 || dir6 == (u8) ~0) + return clib_error_return ( + 0, "Please specify the MSS clamping direction for ip4 and ip6"); + + if (dir4 != MSS_CLAMP_DIR_NONE) + { + if (mss4 == ~0) + return clib_error_return ( + 0, "Please specify the Max Segment Size for ip4"); + if (mss4 >= MSS_CLAMP_UNSET) + return clib_error_return (0, "Invalid Max Segment Size"); + } + if (dir6 != MSS_CLAMP_DIR_NONE) + { + if (mss6 == ~0) + return clib_error_return ( + 0, "Please specify the Max Segment Size for ip6"); + if (mss6 >= MSS_CLAMP_UNSET) + return clib_error_return (0, "Invalid Max Segment Size"); + } + + rv = mssc_enable_disable (sw_if_index, dir4, dir6, mss4, mss6); + + if (rv) + return clib_error_return (0, "Failed: %d = %U", rv, format_vnet_api_errno, + rv); + + return (NULL); +} + +VLIB_CLI_COMMAND (mssc_enable_disable_command, static) = { + .path = "set interface tcp-mss-clamp", + .short_help = "set interface tcp-mss-clamp " + "ip4 [enable|disable|rx|tx] ip4-mss " + "ip6 [enable|disable|rx|tx] ip6-mss ", + .function = mssc_enable_command_fn, +}; + +static u8 * +format_mssc_clamping (u8 *s, va_list *args) +{ + u8 dir = va_arg (*args, u32); + u16 mss = va_arg (*args, u32); +#define DIR2S(d) \ + (((d) == (MSS_CLAMP_DIR_RX | MSS_CLAMP_DIR_TX)) ? \ + "" : \ + (((d) == MSS_CLAMP_DIR_RX) ? " [RX]" : " [TX]")) + + if (MSS_CLAMP_DIR_NONE == dir) + { + return format (s, "disabled"); + } + u32 mss_u32 = mss; + return format (s, "%d%s", mss_u32, DIR2S (dir)); +} + +static clib_error_t * +mssc_show_command_fn (vlib_main_t *vm, unformat_input_t *input, + vlib_cli_command_t *cmd) +{ + mssc_main_t *cm = &mssc_main; + u32 sw_if_index = ~0; + u32 ii; + + while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT) + { + if (unformat (input, "%U", unformat_vnet_sw_interface, vnet_get_main (), + &sw_if_index)) + ; + else + break; + } + + if (sw_if_index == ~0) + { + vec_foreach_index (ii, cm->dir_enabled4) + { + u8 dir4 = cm->dir_enabled4[ii]; + u8 dir6 = cm->dir_enabled6[ii]; + if (MSS_CLAMP_DIR_NONE != dir4 || MSS_CLAMP_DIR_NONE != dir6) + { + u16 mss4 = cm->max_mss4[ii]; + u16 mss6 = cm->max_mss6[ii]; + vlib_cli_output (vm, "%U: ip4: %U ip6: %U", + format_vnet_sw_if_index_name, vnet_get_main (), + ii, format_mssc_clamping, dir4, mss4, + format_mssc_clamping, dir6, mss6); + } + } + } + else + { + u16 mss4, mss6; + u8 dir4, dir6; + mssc_get_mss (sw_if_index, &dir4, &dir6, &mss4, &mss6); + vlib_cli_output (vm, "%U: ip4: %U ip6: %U", format_vnet_sw_if_index_name, + vnet_get_main (), sw_if_index, format_mssc_clamping, + dir4, mss4, format_mssc_clamping, dir6, mss6); + } + + return (NULL); +} + +VLIB_CLI_COMMAND (mssc_show_command, static) = { + .path = "show interface tcp-mss-clamp", + .short_help = "show interface tcp-mss-clamp [interface-name]", + .long_help = "show TCP MSS clamping configurations", + .function = mssc_show_command_fn, +}; + +static clib_error_t * +mssc_init (vlib_main_t *vm) +{ + return NULL; +} + +VLIB_INIT_FUNCTION (mssc_init); + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ -- cgit 1.2.3-korg