1 /* 2 * services/modstack.c - stack of modules 3 * 4 * Copyright (c) 2007, NLnet Labs. All rights reserved. 5 * 6 * This software is open source. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * Neither the name of the NLNET LABS nor the names of its contributors may 20 * be used to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * 39 * This file contains functions to help maintain a stack of modules. 40 */ 41 #include "config.h" 42 #include <ctype.h> 43 #include "services/modstack.h" 44 #include "util/module.h" 45 #include "util/fptr_wlist.h" 46 #include "dns64/dns64.h" 47 #include "iterator/iterator.h" 48 #include "validator/validator.h" 49 50 #ifdef WITH_PYTHONMODULE 51 #include "pythonmod/pythonmod.h" 52 #endif 53 54 /** count number of modules (words) in the string */ 55 static int 56 count_modules(const char* s) 57 { 58 int num = 0; 59 if(!s) 60 return 0; 61 while(*s) { 62 /* skip whitespace */ 63 while(*s && isspace((unsigned char)*s)) 64 s++; 65 if(*s && !isspace((unsigned char)*s)) { 66 /* skip identifier */ 67 num++; 68 while(*s && !isspace((unsigned char)*s)) 69 s++; 70 } 71 } 72 return num; 73 } 74 75 void 76 modstack_init(struct module_stack* stack) 77 { 78 stack->num = 0; 79 stack->mod = NULL; 80 } 81 82 int 83 modstack_config(struct module_stack* stack, const char* module_conf) 84 { 85 int i; 86 verbose(VERB_QUERY, "module config: \"%s\"", module_conf); 87 stack->num = count_modules(module_conf); 88 if(stack->num == 0) { 89 log_err("error: no modules specified"); 90 return 0; 91 } 92 if(stack->num > MAX_MODULE) { 93 log_err("error: too many modules (%d max %d)", 94 stack->num, MAX_MODULE); 95 return 0; 96 } 97 stack->mod = (struct module_func_block**)calloc((size_t) 98 stack->num, sizeof(struct module_func_block*)); 99 if(!stack->mod) { 100 log_err("out of memory"); 101 return 0; 102 } 103 for(i=0; i<stack->num; i++) { 104 stack->mod[i] = module_factory(&module_conf); 105 if(!stack->mod[i]) { 106 log_err("Unknown value for next module: '%s'", 107 module_conf); 108 return 0; 109 } 110 } 111 return 1; 112 } 113 114 /** The list of module names */ 115 const char** 116 module_list_avail(void) 117 { 118 /* these are the modules available */ 119 static const char* names[] = { 120 "dns64", 121 #ifdef WITH_PYTHONMODULE 122 "python", 123 #endif 124 "validator", 125 "iterator", 126 NULL}; 127 return names; 128 } 129 130 /** func block get function type */ 131 typedef struct module_func_block* (*fbgetfunctype)(void); 132 133 /** The list of module func blocks */ 134 static fbgetfunctype* 135 module_funcs_avail(void) 136 { 137 static struct module_func_block* (*fb[])(void) = { 138 &dns64_get_funcblock, 139 #ifdef WITH_PYTHONMODULE 140 &pythonmod_get_funcblock, 141 #endif 142 &val_get_funcblock, 143 &iter_get_funcblock, 144 NULL}; 145 return fb; 146 } 147 148 struct 149 module_func_block* module_factory(const char** str) 150 { 151 int i = 0; 152 const char* s = *str; 153 const char** names = module_list_avail(); 154 fbgetfunctype* fb = module_funcs_avail(); 155 while(*s && isspace((unsigned char)*s)) 156 s++; 157 while(names[i]) { 158 if(strncmp(names[i], s, strlen(names[i])) == 0) { 159 s += strlen(names[i]); 160 *str = s; 161 return (*fb[i])(); 162 } 163 i++; 164 } 165 return NULL; 166 } 167 168 int 169 modstack_setup(struct module_stack* stack, const char* module_conf, 170 struct module_env* env) 171 { 172 int i; 173 if(stack->num != 0) 174 modstack_desetup(stack, env); 175 /* fixed setup of the modules */ 176 if(!modstack_config(stack, module_conf)) { 177 return 0; 178 } 179 env->need_to_validate = 0; /* set by module init below */ 180 for(i=0; i<stack->num; i++) { 181 verbose(VERB_OPS, "init module %d: %s", 182 i, stack->mod[i]->name); 183 fptr_ok(fptr_whitelist_mod_init(stack->mod[i]->init)); 184 if(!(*stack->mod[i]->init)(env, i)) { 185 log_err("module init for module %s failed", 186 stack->mod[i]->name); 187 return 0; 188 } 189 } 190 return 1; 191 } 192 193 void 194 modstack_desetup(struct module_stack* stack, struct module_env* env) 195 { 196 int i; 197 for(i=0; i<stack->num; i++) { 198 fptr_ok(fptr_whitelist_mod_deinit(stack->mod[i]->deinit)); 199 (*stack->mod[i]->deinit)(env, i); 200 } 201 stack->num = 0; 202 free(stack->mod); 203 stack->mod = NULL; 204 } 205 206 int 207 modstack_find(struct module_stack* stack, const char* name) 208 { 209 int i; 210 for(i=0; i<stack->num; i++) { 211 if(strcmp(stack->mod[i]->name, name) == 0) 212 return i; 213 } 214 return -1; 215 } 216