1 /* $OpenBSD: parser.c,v 1.2 2023/04/19 12:58:16 jsg Exp $ */ 2 3 /* 4 * Copyright (c) 2004 Esben Norby <norby@openbsd.org> 5 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #include <sys/types.h> 21 #include <sys/queue.h> 22 #include <sys/socket.h> 23 #include <netinet/in.h> 24 #include <arpa/inet.h> 25 26 #include <net/if.h> 27 #include <netinet/if_ether.h> 28 29 #include <err.h> 30 #include <errno.h> 31 #include <event.h> 32 #include <imsg.h> 33 #include <limits.h> 34 #include <stdio.h> 35 #include <stdlib.h> 36 #include <string.h> 37 38 #include "slaacd.h" 39 #include "parser.h" 40 41 enum token_type { 42 NOTOKEN, 43 ENDTOKEN, 44 INTERFACENAME, 45 KEYWORD 46 }; 47 48 struct token { 49 enum token_type type; 50 const char *keyword; 51 int value; 52 const struct token *next; 53 }; 54 55 static const struct token t_main[]; 56 static const struct token t_log[]; 57 static const struct token t_show[]; 58 static const struct token t_show_interface[]; 59 static const struct token t_send[]; 60 static const struct token t_send_sol[]; 61 62 static const struct token t_main[] = { 63 {KEYWORD, "show", SHOW, t_show}, 64 {KEYWORD, "log", NONE, t_log}, 65 {KEYWORD, "send", NONE, t_send}, 66 {ENDTOKEN, "", NONE, NULL} 67 }; 68 69 static const struct token t_log[] = { 70 {KEYWORD, "verbose", LOG_VERBOSE, NULL}, 71 {KEYWORD, "brief", LOG_BRIEF, NULL}, 72 {ENDTOKEN, "", NONE, NULL} 73 }; 74 75 static const struct token t_show[] = { 76 {KEYWORD, "interface", SHOW_INTERFACE, t_show_interface}, 77 {ENDTOKEN, "", NONE, NULL} 78 }; 79 80 static const struct token t_send[] = { 81 {KEYWORD, "solicitation", SEND_SOLICITATION, t_send_sol}, 82 {ENDTOKEN, "", NONE, NULL} 83 }; 84 static const struct token t_send_sol[] = { 85 {INTERFACENAME, "", SEND_SOLICITATION, NULL}, 86 {ENDTOKEN, "", NONE, NULL} 87 }; 88 89 static const struct token t_show_interface[] = { 90 {NOTOKEN, "", NONE, NULL}, 91 {INTERFACENAME, "", SHOW_INTERFACE, NULL}, 92 {ENDTOKEN, "", NONE, NULL} 93 }; 94 95 static const struct token *match_token(const char *, const struct token *, 96 struct parse_result *); 97 static void show_valid_args(const struct token *); 98 99 struct parse_result * 100 parse(int argc, char *argv[]) 101 { 102 static struct parse_result res; 103 const struct token *table = t_main; 104 const struct token *match; 105 106 memset(&res, 0, sizeof(res)); 107 108 while (argc >= 0) { 109 if ((match = match_token(argv[0], table, &res)) == NULL) { 110 fprintf(stderr, "valid commands/args:\n"); 111 show_valid_args(table); 112 return (NULL); 113 } 114 115 argc--; 116 argv++; 117 118 if (match->type == NOTOKEN || match->next == NULL) 119 break; 120 121 table = match->next; 122 } 123 124 if (argc > 0) { 125 fprintf(stderr, "superfluous argument: %s\n", argv[0]); 126 return (NULL); 127 } 128 129 return (&res); 130 } 131 132 static const struct token * 133 match_token(const char *word, const struct token *table, 134 struct parse_result *res) 135 { 136 u_int i, match; 137 const struct token *t = NULL; 138 139 match = 0; 140 141 for (i = 0; table[i].type != ENDTOKEN; i++) { 142 switch (table[i].type) { 143 case NOTOKEN: 144 if (word == NULL || strlen(word) == 0) { 145 match++; 146 t = &table[i]; 147 } 148 break; 149 case INTERFACENAME: 150 if (!match && word != NULL && strlen(word) > 0) { 151 if ((res->if_index = if_nametoindex(word)) == 0) 152 errx(1, "unknown interface"); 153 match++; 154 t = &table[i]; 155 if (t->value) 156 res->action = t->value; 157 } 158 break; 159 case KEYWORD: 160 if (word != NULL && strncmp(word, table[i].keyword, 161 strlen(word)) == 0) { 162 match++; 163 t = &table[i]; 164 if (t->value) 165 res->action = t->value; 166 } 167 break; 168 case ENDTOKEN: 169 break; 170 } 171 } 172 173 if (match != 1) { 174 if (word == NULL) 175 fprintf(stderr, "missing argument:\n"); 176 else if (match > 1) 177 fprintf(stderr, "ambiguous argument: %s\n", word); 178 else if (match < 1) 179 fprintf(stderr, "unknown argument: %s\n", word); 180 return (NULL); 181 } 182 183 return (t); 184 } 185 186 static void 187 show_valid_args(const struct token *table) 188 { 189 int i; 190 191 for (i = 0; table[i].type != ENDTOKEN; i++) { 192 switch (table[i].type) { 193 case NOTOKEN: 194 fprintf(stderr, " <cr>\n"); 195 break; 196 case INTERFACENAME: 197 fprintf(stderr, " <interface>\n"); 198 break; 199 case KEYWORD: 200 fprintf(stderr, " %s\n", table[i].keyword); 201 break; 202 case ENDTOKEN: 203 break; 204 } 205 } 206 } 207