1 /* 2 * m_csum.c checksum updating action 3 * 4 * This program is free software; you can distribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 * 9 * Authors: Gregoire Baron <baronchon (at) n7mm.org> 10 */ 11 12 #include <stdio.h> 13 #include <stdlib.h> 14 #include <string.h> 15 #include <unistd.h> 16 17 #include <linux/tc_act/tc_csum.h> 18 19 #include "utils.h" 20 #include "tc_util.h" 21 22 static void 23 explain(void) 24 { 25 fprintf(stderr, "Usage: ... csum <UPDATE>\n" 26 "Where: UPDATE := <TARGET> [<UPDATE>]\n" 27 " TARGET := { ip4h | icmp | igmp | tcp | udp | udplite | sctp | <SWEETS> }\n" 28 " SWEETS := { and | or | \'+\' }\n"); 29 } 30 31 static void 32 usage(void) 33 { 34 explain(); 35 exit(-1); 36 } 37 38 static int 39 parse_csum_args(int *argc_p, char ***argv_p, struct tc_csum *sel) 40 { 41 int argc = *argc_p; 42 char **argv = *argv_p; 43 44 if (argc <= 0) 45 return -1; 46 47 while (argc > 0) { 48 if ((matches(*argv, "iph") == 0) || 49 (matches(*argv, "ip4h") == 0) || 50 (matches(*argv, "ipv4h") == 0)) 51 sel->update_flags |= TCA_CSUM_UPDATE_FLAG_IPV4HDR; 52 53 else if (matches(*argv, "icmp") == 0) 54 sel->update_flags |= TCA_CSUM_UPDATE_FLAG_ICMP; 55 56 else if (matches(*argv, "igmp") == 0) 57 sel->update_flags |= TCA_CSUM_UPDATE_FLAG_IGMP; 58 59 else if (matches(*argv, "tcp") == 0) 60 sel->update_flags |= TCA_CSUM_UPDATE_FLAG_TCP; 61 62 else if (matches(*argv, "udp") == 0) 63 sel->update_flags |= TCA_CSUM_UPDATE_FLAG_UDP; 64 65 else if (matches(*argv, "udplite") == 0) 66 sel->update_flags |= TCA_CSUM_UPDATE_FLAG_UDPLITE; 67 68 else if (matches(*argv, "sctp") == 0) 69 sel->update_flags |= TCA_CSUM_UPDATE_FLAG_SCTP; 70 71 else if ((matches(*argv, "and") == 0) || 72 (matches(*argv, "or") == 0) || 73 (matches(*argv, "+") == 0)) 74 ; /* just ignore: ... csum iph and tcp or udp */ 75 else 76 break; 77 argc--; 78 argv++; 79 } 80 81 *argc_p = argc; 82 *argv_p = argv; 83 84 return 0; 85 } 86 87 static int 88 parse_csum(struct action_util *a, int *argc_p, 89 char ***argv_p, int tca_id, struct nlmsghdr *n) 90 { 91 struct tc_csum sel = {}; 92 93 int argc = *argc_p; 94 char **argv = *argv_p; 95 int ok = 0; 96 struct rtattr *tail; 97 98 while (argc > 0) { 99 if (matches(*argv, "csum") == 0) { 100 NEXT_ARG(); 101 if (parse_csum_args(&argc, &argv, &sel)) { 102 fprintf(stderr, "Illegal csum construct (%s)\n", 103 *argv); 104 explain(); 105 return -1; 106 } 107 ok++; 108 continue; 109 } else if (matches(*argv, "help") == 0) { 110 usage(); 111 } else { 112 break; 113 } 114 } 115 116 if (!ok) { 117 explain(); 118 return -1; 119 } 120 121 if (sel.update_flags == 0) { 122 fprintf(stderr, "Illegal csum construct, empty <UPDATE> list\n"); 123 return -1; 124 } 125 126 parse_action_control_dflt(&argc, &argv, &sel.action, false, TC_ACT_OK); 127 128 if (argc) { 129 if (matches(*argv, "index") == 0) { 130 NEXT_ARG(); 131 if (get_u32(&sel.index, *argv, 10)) { 132 fprintf(stderr, "Illegal \"index\" (%s) <csum>\n", 133 *argv); 134 return -1; 135 } 136 argc--; 137 argv++; 138 } 139 } 140 141 tail = NLMSG_TAIL(n); 142 addattr_l(n, MAX_MSG, tca_id, NULL, 0); 143 addattr_l(n, MAX_MSG, TCA_CSUM_PARMS, &sel, sizeof(sel)); 144 tail->rta_len = (char *)NLMSG_TAIL(n) - (char *)tail; 145 146 *argc_p = argc; 147 *argv_p = argv; 148 149 return 0; 150 } 151 152 static int 153 print_csum(struct action_util *au, FILE *f, struct rtattr *arg) 154 { 155 struct tc_csum *sel; 156 157 struct rtattr *tb[TCA_CSUM_MAX + 1]; 158 159 char *uflag_1 = ""; 160 char *uflag_2 = ""; 161 char *uflag_3 = ""; 162 char *uflag_4 = ""; 163 char *uflag_5 = ""; 164 char *uflag_6 = ""; 165 char *uflag_7 = ""; 166 167 int uflag_count = 0; 168 169 if (arg == NULL) 170 return -1; 171 172 parse_rtattr_nested(tb, TCA_CSUM_MAX, arg); 173 174 if (tb[TCA_CSUM_PARMS] == NULL) { 175 fprintf(f, "[NULL csum parameters]"); 176 return -1; 177 } 178 sel = RTA_DATA(tb[TCA_CSUM_PARMS]); 179 180 if (sel->update_flags & TCA_CSUM_UPDATE_FLAG_IPV4HDR) { 181 uflag_1 = "iph"; 182 uflag_count++; 183 } 184 #define CSUM_UFLAG_BUFFER(flag_buffer, flag_value, flag_string) \ 185 do { \ 186 if (sel->update_flags & flag_value) { \ 187 flag_buffer = uflag_count > 0 ? \ 188 ", " flag_string : flag_string; \ 189 uflag_count++; \ 190 } \ 191 } while (0) 192 CSUM_UFLAG_BUFFER(uflag_2, TCA_CSUM_UPDATE_FLAG_ICMP, "icmp"); 193 CSUM_UFLAG_BUFFER(uflag_3, TCA_CSUM_UPDATE_FLAG_IGMP, "igmp"); 194 CSUM_UFLAG_BUFFER(uflag_4, TCA_CSUM_UPDATE_FLAG_TCP, "tcp"); 195 CSUM_UFLAG_BUFFER(uflag_5, TCA_CSUM_UPDATE_FLAG_UDP, "udp"); 196 CSUM_UFLAG_BUFFER(uflag_6, TCA_CSUM_UPDATE_FLAG_UDPLITE, "udplite"); 197 CSUM_UFLAG_BUFFER(uflag_7, TCA_CSUM_UPDATE_FLAG_SCTP, "sctp"); 198 if (!uflag_count) { 199 uflag_1 = "?empty"; 200 } 201 202 fprintf(f, "csum (%s%s%s%s%s%s%s) ", 203 uflag_1, uflag_2, uflag_3, 204 uflag_4, uflag_5, uflag_6, uflag_7); 205 print_action_control(f, "action ", sel->action, "\n"); 206 fprintf(f, "\tindex %u ref %d bind %d", sel->index, sel->refcnt, 207 sel->bindcnt); 208 209 if (show_stats) { 210 if (tb[TCA_CSUM_TM]) { 211 struct tcf_t *tm = RTA_DATA(tb[TCA_CSUM_TM]); 212 213 print_tm(f, tm); 214 } 215 } 216 fprintf(f, "\n"); 217 218 return 0; 219 } 220 221 struct action_util csum_action_util = { 222 .id = "csum", 223 .parse_aopt = parse_csum, 224 .print_aopt = print_csum, 225 }; 226
