350
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1
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2 /*
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3 * Copyright (C) Igor Sysoev
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4 */
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5
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6
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7 #include <ngx_config.h>
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8 #include <ngx_core.h>
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9 #include <ngx_event.h>
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10
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11
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12 #define NGX_RESOLVER_UDP_SIZE 4096
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13
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14
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15 typedef struct {
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16 u_char ident_hi;
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17 u_char ident_lo;
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18 u_char flags_hi;
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19 u_char flags_lo;
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20 u_char nqs_hi;
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21 u_char nqs_lo;
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22 u_char nan_hi;
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23 u_char nan_lo;
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24 u_char nns_hi;
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25 u_char nns_lo;
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26 u_char nar_hi;
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27 u_char nar_lo;
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28 } ngx_resolver_query_t;
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29
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30
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31 typedef struct {
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32 u_char type_hi;
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33 u_char type_lo;
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34 u_char class_hi;
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35 u_char class_lo;
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36 } ngx_resolver_qs_t;
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37
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38
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39 typedef struct {
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40 u_char type_hi;
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41 u_char type_lo;
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42 u_char class_hi;
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43 u_char class_lo;
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44 u_char ttl[4];
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45 u_char len_hi;
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46 u_char len_lo;
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47 } ngx_resolver_an_t;
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48
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49
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50 ngx_int_t ngx_udp_connect(ngx_udp_connection_t *uc);
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51
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52
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366
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53 static void ngx_resolver_cleanup(void *data);
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54 static void ngx_resolver_cleanup_tree(ngx_resolver_t *r, ngx_rbtree_t *tree);
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350
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55 static ngx_int_t ngx_resolve_name_locked(ngx_resolver_t *r,
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56 ngx_resolver_ctx_t *ctx);
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57 static void ngx_resolver_expire(ngx_resolver_t *r, ngx_rbtree_t *tree,
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58 ngx_queue_t *queue);
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59 static ngx_int_t ngx_resolver_send_query(ngx_resolver_t *r,
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60 ngx_resolver_node_t *rn);
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61 static ngx_int_t ngx_resolver_create_name_query(ngx_resolver_node_t *rn,
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62 ngx_resolver_ctx_t *ctx);
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63 static ngx_int_t ngx_resolver_create_addr_query(ngx_resolver_node_t *rn,
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64 ngx_resolver_ctx_t *ctx);
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65 static void ngx_resolver_resend_handler(ngx_event_t *ev);
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66 static time_t ngx_resolver_resend(ngx_resolver_t *r, ngx_rbtree_t *tree,
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67 ngx_queue_t *queue);
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68 static void ngx_resolver_read_response(ngx_event_t *rev);
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69 static void ngx_resolver_process_response(ngx_resolver_t *r, u_char *buf,
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70 size_t n);
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71 static void ngx_resolver_process_a(ngx_resolver_t *r, u_char *buf, size_t n,
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356
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72 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan, ngx_uint_t ans);
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350
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73 static void ngx_resolver_process_ptr(ngx_resolver_t *r, u_char *buf, size_t n,
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356
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74 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan);
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350
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75 static ngx_resolver_node_t *ngx_resolver_lookup_name(ngx_resolver_t *r,
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76 ngx_str_t *name, uint32_t hash);
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77 static ngx_resolver_node_t *ngx_resolver_lookup_addr(ngx_resolver_t *r,
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78 in_addr_t addr);
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79 static void ngx_resolver_rbtree_insert_value(ngx_rbtree_node_t *temp,
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80 ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel);
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81 static ngx_int_t ngx_resolver_copy(ngx_resolver_t *r, ngx_str_t *name,
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82 u_char *buf, u_char *src, u_char *last);
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83 static void ngx_resolver_timeout_handler(ngx_event_t *ev);
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84 static void ngx_resolver_free_node(ngx_resolver_t *r, ngx_resolver_node_t *rn);
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85 static void *ngx_resolver_alloc(ngx_resolver_t *r, size_t size);
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366
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86 static void *ngx_resolver_calloc(ngx_resolver_t *r, size_t size);
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350
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87 static void ngx_resolver_free(ngx_resolver_t *r, void *p);
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88 static void ngx_resolver_free_locked(ngx_resolver_t *r, void *p);
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89 static void *ngx_resolver_dup(ngx_resolver_t *r, void *src, size_t size);
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560
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90 static u_char *ngx_resolver_log_error(ngx_log_t *log, u_char *buf, size_t len);
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350
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91
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92
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93 ngx_resolver_t *
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646
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94 ngx_resolver_create(ngx_conf_t *cf, ngx_str_t *names, ngx_uint_t n)
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350
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95 {
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646
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96 ngx_url_t u;
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97 ngx_uint_t i;
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350
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98 ngx_resolver_t *r;
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366
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99 ngx_pool_cleanup_t *cln;
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350
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100 ngx_udp_connection_t *uc;
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101
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366
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102 cln = ngx_pool_cleanup_add(cf->pool, 0);
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103 if (cln == NULL) {
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104 return NULL;
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105 }
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106
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107 cln->handler = ngx_resolver_cleanup;
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108
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109 r = ngx_calloc(sizeof(ngx_resolver_t), cf->log);
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350
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110 if (r == NULL) {
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111 return NULL;
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112 }
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113
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646
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114 if (n) {
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115 if (ngx_array_init(&r->udp_connections, cf->pool, n,
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116 sizeof(ngx_udp_connection_t))
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117 != NGX_OK)
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118 {
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119 return NULL;
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120 }
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121 }
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122
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366
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123 cln->data = r;
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124
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125 r->event = ngx_calloc(sizeof(ngx_event_t), cf->log);
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350
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126 if (r->event == NULL) {
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127 return NULL;
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128 }
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129
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354
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130 ngx_rbtree_init(&r->name_rbtree, &r->name_sentinel,
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131 ngx_resolver_rbtree_insert_value);
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132
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133 ngx_rbtree_init(&r->addr_rbtree, &r->addr_sentinel,
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134 ngx_rbtree_insert_value);
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135
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136 ngx_queue_init(&r->name_resend_queue);
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137 ngx_queue_init(&r->addr_resend_queue);
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138
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139 ngx_queue_init(&r->name_expire_queue);
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140 ngx_queue_init(&r->addr_expire_queue);
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350
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141
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142 r->event->handler = ngx_resolver_resend_handler;
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143 r->event->data = r;
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484
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144 r->event->log = &cf->cycle->new_log;
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350
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145 r->ident = -1;
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146
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147 r->resend_timeout = 5;
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148 r->expire = 30;
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149 r->valid = 300;
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150
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484
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151 r->log = &cf->cycle->new_log;
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598
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152 r->log_level = NGX_LOG_ERR;
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350
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153
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646
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154 for (i = 0; i < n; i++) {
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155 ngx_memzero(&u, sizeof(ngx_url_t));
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156
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157 u.host = names[i];
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158 u.port = 53;
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159
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160 if (ngx_inet_resolve_host(cf->pool, &u) != NGX_OK) {
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161 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%V: %s", &u.host, u.err);
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162 return NULL;
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163 }
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164
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165 uc = ngx_array_push(&r->udp_connections);
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354
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166 if (uc == NULL) {
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167 return NULL;
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168 }
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169
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646
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170 ngx_memzero(uc, sizeof(ngx_udp_connection_t));
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171
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172 uc->sockaddr = u.addrs->sockaddr;
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173 uc->socklen = u.addrs->socklen;
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174 uc->server = u.addrs->name;
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560
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175
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176 uc->log = cf->cycle->new_log;
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177 uc->log.handler = ngx_resolver_log_error;
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178 uc->log.data = uc;
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179 uc->log.action = "resolving";
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354
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180 }
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350
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181
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182 return r;
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183 }
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184
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185
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366
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186 static void
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187 ngx_resolver_cleanup(void *data)
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188 {
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189 ngx_resolver_t *r = data;
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190
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646
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191 ngx_uint_t i;
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192 ngx_udp_connection_t *uc;
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193
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366
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194 if (r) {
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195 ngx_log_debug0(NGX_LOG_DEBUG_CORE, ngx_cycle->log, 0,
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196 "cleanup resolver");
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197
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198 ngx_resolver_cleanup_tree(r, &r->name_rbtree);
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199
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200 ngx_resolver_cleanup_tree(r, &r->addr_rbtree);
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201
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202 if (r->event) {
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203 ngx_free(r->event);
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204 }
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205
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646
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206
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207 uc = r->udp_connections.elts;
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208
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209 for (i = 0; i < r->udp_connections.nelts; i++) {
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210 if (uc[i].connection) {
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211 ngx_close_connection(uc[i].connection);
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366
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212 }
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213 }
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214
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215 ngx_free(r);
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216 }
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217 }
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218
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219
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220 static void
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221 ngx_resolver_cleanup_tree(ngx_resolver_t *r, ngx_rbtree_t *tree)
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222 {
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223 ngx_resolver_ctx_t *ctx, *next;
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224 ngx_resolver_node_t *rn;
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225
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226 while (tree->root != tree->sentinel) {
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227
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228 rn = (ngx_resolver_node_t *) ngx_rbtree_min(tree->root, tree->sentinel);
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229
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230 ngx_queue_remove(&rn->queue);
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231
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232 for (ctx = rn->waiting; ctx; ctx = next) {
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376
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233 next = ctx->next;
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366
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234
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235 if (ctx->event) {
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236 ngx_resolver_free(r, ctx->event);
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237 }
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238
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239 ngx_resolver_free(r, ctx);
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240 }
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241
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242 ngx_rbtree_delete(tree, &rn->node);
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243
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244 ngx_resolver_free_node(r, rn);
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245 }
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246 }
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247
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248
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350
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249 ngx_resolver_ctx_t *
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250 ngx_resolve_start(ngx_resolver_t *r, ngx_resolver_ctx_t *temp)
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251 {
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252 in_addr_t addr;
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253 ngx_resolver_ctx_t *ctx;
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254
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255 if (temp) {
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256 addr = ngx_inet_addr(temp->name.data, temp->name.len);
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257
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258 if (addr != INADDR_NONE) {
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259 temp->resolver = r;
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260 temp->state = NGX_OK;
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261 temp->naddrs = 1;
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262 temp->addrs = &temp->addr;
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263 temp->addr = addr;
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264 temp->quick = 1;
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265
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266 return temp;
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267 }
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268 }
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269
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646
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270 if (r->udp_connections.nelts == 0) {
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354
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271 return NGX_NO_RESOLVER;
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272 }
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273
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350
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274 ctx = ngx_resolver_calloc(r, sizeof(ngx_resolver_ctx_t));
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275
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276 if (ctx) {
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277 ctx->resolver = r;
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278 }
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279
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280 return ctx;
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281 }
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282
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283
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284 ngx_int_t
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285 ngx_resolve_name(ngx_resolver_ctx_t *ctx)
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286 {
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287 ngx_int_t rc;
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288 ngx_resolver_t *r;
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289
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290 r = ctx->resolver;
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291
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292 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
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293 "resolve: \"%V\"", &ctx->name);
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294
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295 if (ctx->quick) {
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296 ctx->handler(ctx);
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297 return NGX_OK;
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298 }
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299
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300 /* lock name mutex */
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301
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302 rc = ngx_resolve_name_locked(r, ctx);
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303
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304 if (rc == NGX_OK) {
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305 return NGX_OK;
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306 }
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307
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308 /* unlock name mutex */
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309
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310 if (rc == NGX_AGAIN) {
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311 return NGX_OK;
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312 }
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313
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366
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314 /* NGX_ERROR */
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350
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315
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316 if (ctx->event) {
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366
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317 ngx_resolver_free(r, ctx->event);
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350
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318 }
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319
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366
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320 ngx_resolver_free(r, ctx);
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350
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321
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322 return NGX_ERROR;
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323 }
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324
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325
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326 void
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327 ngx_resolve_name_done(ngx_resolver_ctx_t *ctx)
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328 {
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329 uint32_t hash;
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330 ngx_resolver_t *r;
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331 ngx_resolver_ctx_t *w, **p;
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332 ngx_resolver_node_t *rn;
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333
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334 r = ctx->resolver;
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335
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336 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
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337 "resolve name done: %i", ctx->state);
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338
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339 if (ctx->quick) {
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340 return;
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341 }
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342
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343 if (ctx->event && ctx->event->timer_set) {
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344 ngx_del_timer(ctx->event);
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345 }
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346
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347 /* lock name mutex */
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348
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349 if (ctx->state == NGX_AGAIN || ctx->state == NGX_RESOLVE_TIMEDOUT) {
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350
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351 hash = ngx_crc32_short(ctx->name.data, ctx->name.len);
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352
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353 rn = ngx_resolver_lookup_name(r, &ctx->name, hash);
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354
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355 if (rn) {
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356 p = &rn->waiting;
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357 w = rn->waiting;
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358
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359 while (w) {
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360 if (w == ctx) {
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361 *p = w->next;
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362
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363 goto done;
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364 }
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365
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366 p = &w->next;
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367 w = w->next;
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368 }
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369 }
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370
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371 ngx_log_error(NGX_LOG_ALERT, r->log, 0,
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372 "could not cancel %V resolving", &ctx->name);
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373 }
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374
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375 done:
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376
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377 ngx_resolver_expire(r, &r->name_rbtree, &r->name_expire_queue);
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378
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379 /* unlock name mutex */
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380
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366
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381 /* lock alloc mutex */
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382
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383 if (ctx->event) {
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384 ngx_resolver_free_locked(r, ctx->event);
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385 }
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386
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387 ngx_resolver_free_locked(r, ctx);
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388
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389 /* unlock alloc mutex */
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350
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390 }
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391
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392
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393 /* NGX_RESOLVE_A only */
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394
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395 static ngx_int_t
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396 ngx_resolve_name_locked(ngx_resolver_t *r, ngx_resolver_ctx_t *ctx)
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397 {
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398 uint32_t hash;
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399 in_addr_t addr, *addrs;
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372
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400 ngx_int_t rc;
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350
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401 ngx_uint_t naddrs;
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402 ngx_resolver_ctx_t *next;
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403 ngx_resolver_node_t *rn;
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404
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405 hash = ngx_crc32_short(ctx->name.data, ctx->name.len);
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406
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407 rn = ngx_resolver_lookup_name(r, &ctx->name, hash);
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408
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409 if (rn) {
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410
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411 if (rn->valid >= ngx_time()) {
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412
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413 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolve cached");
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414
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415 ngx_queue_remove(&rn->queue);
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416
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417 rn->expire = ngx_time() + r->expire;
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418
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419 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue);
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420
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421 naddrs = rn->naddrs;
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422
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423 if (naddrs) {
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424
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425 /* NGX_RESOLVE_A answer */
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426
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427 if (naddrs != 1) {
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428 addr = 0;
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429 addrs = ngx_resolver_dup(r, rn->u.addrs,
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430 naddrs * sizeof(in_addr_t));
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431 if (addrs == NULL) {
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432 return NGX_ERROR;
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433 }
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434
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435 } else {
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436 addr = rn->u.addr;
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437 addrs = NULL;
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438 }
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439
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440 ctx->next = rn->waiting;
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441 rn->waiting = NULL;
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442
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443 /* unlock name mutex */
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444
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445 do {
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446 ctx->state = NGX_OK;
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447 ctx->naddrs = naddrs;
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448 ctx->addrs = (naddrs == 1) ? &ctx->addr : addrs;
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449 ctx->addr = addr;
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450 next = ctx->next;
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451
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452 ctx->handler(ctx);
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453
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454 ctx = next;
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455 } while (ctx);
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456
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457 if (addrs) {
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458 ngx_resolver_free(r, addrs);
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459 }
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460
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461 return NGX_OK;
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462 }
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463
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464 /* NGX_RESOLVE_CNAME */
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465
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372
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466 if (ctx->recursion++ < NGX_RESOLVER_MAX_RECURSION) {
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467
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468 ctx->name.len = rn->cnlen;
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469 ctx->name.data = rn->u.cname;
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470
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471 return ngx_resolve_name_locked(r, ctx);
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472 }
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473
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|
474 ctx->next = rn->waiting;
|
|
475 rn->waiting = NULL;
|
|
476
|
|
477 /* unlock name mutex */
|
|
478
|
|
479 do {
|
|
480 ctx->state = NGX_RESOLVE_NXDOMAIN;
|
|
481 next = ctx->next;
|
|
482
|
|
483 ctx->handler(ctx);
|
|
484
|
|
485 ctx = next;
|
|
486 } while (ctx);
|
|
487
|
|
488 return NGX_OK;
|
350
|
489 }
|
|
490
|
|
491 if (rn->waiting) {
|
|
492
|
|
493 ctx->next = rn->waiting;
|
|
494 rn->waiting = ctx;
|
542
|
495 ctx->state = NGX_AGAIN;
|
350
|
496
|
|
497 return NGX_AGAIN;
|
|
498 }
|
|
499
|
|
500 ngx_queue_remove(&rn->queue);
|
|
501
|
|
502 /* lock alloc mutex */
|
|
503
|
|
504 ngx_resolver_free_locked(r, rn->query);
|
372
|
505 rn->query = NULL;
|
350
|
506
|
|
507 if (rn->cnlen) {
|
|
508 ngx_resolver_free_locked(r, rn->u.cname);
|
|
509 }
|
|
510
|
|
511 if (rn->naddrs > 1) {
|
|
512 ngx_resolver_free_locked(r, rn->u.addrs);
|
|
513 }
|
|
514
|
|
515 /* unlock alloc mutex */
|
|
516
|
|
517 } else {
|
|
518
|
|
519 rn = ngx_resolver_alloc(r, sizeof(ngx_resolver_node_t));
|
|
520 if (rn == NULL) {
|
|
521 return NGX_ERROR;
|
|
522 }
|
|
523
|
|
524 rn->name = ngx_resolver_dup(r, ctx->name.data, ctx->name.len);
|
|
525 if (rn->name == NULL) {
|
|
526 ngx_resolver_free(r, rn);
|
|
527 return NGX_ERROR;
|
|
528 }
|
|
529
|
|
530 rn->node.key = hash;
|
|
531 rn->nlen = (u_short) ctx->name.len;
|
372
|
532 rn->query = NULL;
|
350
|
533
|
|
534 ngx_rbtree_insert(&r->name_rbtree, &rn->node);
|
|
535 }
|
|
536
|
372
|
537 rc = ngx_resolver_create_name_query(rn, ctx);
|
|
538
|
|
539 if (rc == NGX_ERROR) {
|
350
|
540 goto failed;
|
|
541 }
|
|
542
|
372
|
543 if (rc == NGX_DECLINED) {
|
|
544 ngx_rbtree_delete(&r->name_rbtree, &rn->node);
|
|
545
|
|
546 ngx_resolver_free(r, rn->query);
|
|
547 ngx_resolver_free(r, rn->name);
|
|
548 ngx_resolver_free(r, rn);
|
|
549
|
|
550 ctx->state = NGX_RESOLVE_NXDOMAIN;
|
|
551 ctx->handler(ctx);
|
|
552
|
|
553 return NGX_OK;
|
|
554 }
|
|
555
|
350
|
556 if (ngx_resolver_send_query(r, rn) != NGX_OK) {
|
|
557 goto failed;
|
|
558 }
|
|
559
|
|
560 if (ctx->event == NULL) {
|
|
561 ctx->event = ngx_resolver_calloc(r, sizeof(ngx_event_t));
|
|
562 if (ctx->event == NULL) {
|
|
563 goto failed;
|
|
564 }
|
|
565
|
|
566 ctx->event->handler = ngx_resolver_timeout_handler;
|
|
567 ctx->event->data = ctx;
|
|
568 ctx->event->log = r->log;
|
|
569 ctx->ident = -1;
|
|
570
|
|
571 ngx_add_timer(ctx->event, ctx->timeout);
|
|
572 }
|
|
573
|
|
574 if (ngx_queue_empty(&r->name_resend_queue)) {
|
|
575 ngx_add_timer(r->event, (ngx_msec_t) (r->resend_timeout * 1000));
|
|
576 }
|
|
577
|
|
578 rn->expire = ngx_time() + r->resend_timeout;
|
|
579
|
|
580 ngx_queue_insert_head(&r->name_resend_queue, &rn->queue);
|
|
581
|
|
582 rn->cnlen = 0;
|
|
583 rn->naddrs = 0;
|
|
584 rn->valid = 0;
|
|
585 rn->waiting = ctx;
|
|
586
|
|
587 ctx->state = NGX_AGAIN;
|
|
588
|
|
589 return NGX_AGAIN;
|
|
590
|
|
591 failed:
|
|
592
|
|
593 ngx_rbtree_delete(&r->name_rbtree, &rn->node);
|
|
594
|
372
|
595 if (rn->query) {
|
|
596 ngx_resolver_free(r, rn->query);
|
|
597 }
|
|
598
|
350
|
599 ngx_resolver_free(r, rn->name);
|
|
600
|
|
601 ngx_resolver_free(r, rn);
|
|
602
|
|
603 return NGX_ERROR;
|
|
604 }
|
|
605
|
|
606
|
|
607 ngx_int_t
|
|
608 ngx_resolve_addr(ngx_resolver_ctx_t *ctx)
|
|
609 {
|
442
|
610 u_char *name;
|
350
|
611 ngx_resolver_t *r;
|
|
612 ngx_resolver_node_t *rn;
|
|
613
|
|
614 r = ctx->resolver;
|
|
615
|
|
616 ctx->addr = ntohl(ctx->addr);
|
|
617
|
|
618 /* lock addr mutex */
|
|
619
|
|
620 rn = ngx_resolver_lookup_addr(r, ctx->addr);
|
|
621
|
|
622 if (rn) {
|
|
623
|
|
624 if (rn->valid >= ngx_time()) {
|
|
625
|
|
626 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolve cached");
|
|
627
|
|
628 ngx_queue_remove(&rn->queue);
|
|
629
|
|
630 rn->expire = ngx_time() + r->expire;
|
|
631
|
|
632 ngx_queue_insert_head(&r->addr_expire_queue, &rn->queue);
|
|
633
|
442
|
634 name = ngx_resolver_dup(r, rn->name, rn->nlen);
|
|
635 if (name == NULL) {
|
350
|
636 goto failed;
|
|
637 }
|
|
638
|
442
|
639 ctx->name.len = rn->nlen;
|
|
640 ctx->name.data = name;
|
|
641
|
350
|
642 /* unlock addr mutex */
|
|
643
|
|
644 ctx->state = NGX_OK;
|
|
645
|
|
646 ctx->handler(ctx);
|
|
647
|
442
|
648 ngx_resolver_free(r, name);
|
350
|
649
|
|
650 return NGX_OK;
|
|
651 }
|
|
652
|
|
653 if (rn->waiting) {
|
|
654
|
|
655 ctx->next = rn->waiting;
|
|
656 rn->waiting = ctx;
|
542
|
657 ctx->state = NGX_AGAIN;
|
350
|
658
|
442
|
659 /* unlock addr mutex */
|
|
660
|
|
661 return NGX_OK;
|
350
|
662 }
|
|
663
|
|
664 ngx_queue_remove(&rn->queue);
|
|
665
|
|
666 ngx_resolver_free(r, rn->query);
|
372
|
667 rn->query = NULL;
|
350
|
668
|
|
669 } else {
|
|
670 rn = ngx_resolver_alloc(r, sizeof(ngx_resolver_node_t));
|
|
671 if (rn == NULL) {
|
|
672 goto failed;
|
|
673 }
|
|
674
|
|
675 rn->node.key = ctx->addr;
|
372
|
676 rn->query = NULL;
|
350
|
677
|
|
678 ngx_rbtree_insert(&r->addr_rbtree, &rn->node);
|
|
679 }
|
|
680
|
|
681 if (ngx_resolver_create_addr_query(rn, ctx) != NGX_OK) {
|
|
682 goto failed;
|
|
683 }
|
|
684
|
|
685 if (ngx_resolver_send_query(r, rn) != NGX_OK) {
|
|
686 goto failed;
|
|
687 }
|
|
688
|
|
689 ctx->event = ngx_resolver_calloc(r, sizeof(ngx_event_t));
|
|
690 if (ctx->event == NULL) {
|
|
691 goto failed;
|
|
692 }
|
|
693
|
|
694 ctx->event->handler = ngx_resolver_timeout_handler;
|
|
695 ctx->event->data = ctx;
|
|
696 ctx->event->log = r->log;
|
|
697 ctx->ident = -1;
|
|
698
|
|
699 ngx_add_timer(ctx->event, ctx->timeout);
|
|
700
|
|
701 if (ngx_queue_empty(&r->addr_resend_queue)) {
|
|
702 ngx_add_timer(r->event, (ngx_msec_t) (r->resend_timeout * 1000));
|
|
703 }
|
|
704
|
|
705 rn->expire = ngx_time() + r->resend_timeout;
|
|
706
|
|
707 ngx_queue_insert_head(&r->addr_resend_queue, &rn->queue);
|
|
708
|
|
709 rn->cnlen = 0;
|
|
710 rn->naddrs = 0;
|
|
711 rn->name = NULL;
|
|
712 rn->nlen = 0;
|
|
713 rn->valid = 0;
|
|
714 rn->waiting = ctx;
|
|
715
|
|
716 /* unlock addr mutex */
|
|
717
|
|
718 ctx->state = NGX_AGAIN;
|
|
719
|
|
720 return NGX_OK;
|
|
721
|
|
722 failed:
|
|
723
|
|
724 if (rn) {
|
|
725 ngx_rbtree_delete(&r->addr_rbtree, &rn->node);
|
|
726
|
372
|
727 if (rn->query) {
|
|
728 ngx_resolver_free(r, rn->query);
|
|
729 }
|
|
730
|
350
|
731 ngx_resolver_free(r, rn);
|
|
732 }
|
|
733
|
|
734 /* unlock addr mutex */
|
|
735
|
|
736 if (ctx->event) {
|
366
|
737 ngx_resolver_free(r, ctx->event);
|
350
|
738 }
|
|
739
|
366
|
740 ngx_resolver_free(r, ctx);
|
350
|
741
|
|
742 return NGX_ERROR;
|
|
743 }
|
|
744
|
|
745
|
|
746 void
|
|
747 ngx_resolve_addr_done(ngx_resolver_ctx_t *ctx)
|
|
748 {
|
|
749 in_addr_t addr;
|
|
750 ngx_resolver_t *r;
|
|
751 ngx_resolver_ctx_t *w, **p;
|
|
752 ngx_resolver_node_t *rn;
|
|
753
|
|
754 r = ctx->resolver;
|
|
755
|
|
756 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
757 "resolve addr done: %i", ctx->state);
|
|
758
|
|
759 if (ctx->event && ctx->event->timer_set) {
|
|
760 ngx_del_timer(ctx->event);
|
|
761 }
|
|
762
|
|
763 /* lock addr mutex */
|
|
764
|
|
765 if (ctx->state == NGX_AGAIN || ctx->state == NGX_RESOLVE_TIMEDOUT) {
|
|
766
|
|
767 rn = ngx_resolver_lookup_addr(r, ctx->addr);
|
|
768
|
|
769 if (rn) {
|
|
770 p = &rn->waiting;
|
|
771 w = rn->waiting;
|
|
772
|
|
773 while (w) {
|
|
774 if (w == ctx) {
|
|
775 *p = w->next;
|
|
776
|
|
777 goto done;
|
|
778 }
|
|
779
|
|
780 p = &w->next;
|
|
781 w = w->next;
|
|
782 }
|
|
783 }
|
|
784
|
|
785 addr = ntohl(ctx->addr);
|
|
786
|
|
787 ngx_log_error(NGX_LOG_ALERT, r->log, 0,
|
|
788 "could not cancel %ud.%ud.%ud.%ud resolving",
|
|
789 (addr >> 24) & 0xff, (addr >> 16) & 0xff,
|
|
790 (addr >> 8) & 0xff, addr & 0xff);
|
|
791 }
|
|
792
|
|
793 done:
|
|
794
|
|
795 ngx_resolver_expire(r, &r->addr_rbtree, &r->addr_expire_queue);
|
|
796
|
|
797 /* unlock addr mutex */
|
|
798
|
366
|
799 /* lock alloc mutex */
|
|
800
|
|
801 if (ctx->event) {
|
|
802 ngx_resolver_free_locked(r, ctx->event);
|
|
803 }
|
|
804
|
|
805 ngx_resolver_free_locked(r, ctx);
|
|
806
|
|
807 /* unlock alloc mutex */
|
350
|
808 }
|
|
809
|
|
810
|
|
811 static void
|
|
812 ngx_resolver_expire(ngx_resolver_t *r, ngx_rbtree_t *tree, ngx_queue_t *queue)
|
|
813 {
|
|
814 time_t now;
|
|
815 ngx_uint_t i;
|
|
816 ngx_queue_t *q;
|
|
817 ngx_resolver_node_t *rn;
|
|
818
|
|
819 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver expire");
|
|
820
|
|
821 now = ngx_time();
|
|
822
|
|
823 for (i = 0; i < 2; i++) {
|
|
824 if (ngx_queue_empty(queue)) {
|
|
825 return;
|
|
826 }
|
|
827
|
|
828 q = ngx_queue_last(queue);
|
|
829
|
|
830 rn = ngx_queue_data(q, ngx_resolver_node_t, queue);
|
|
831
|
|
832 if (now <= rn->expire) {
|
|
833 return;
|
|
834 }
|
|
835
|
358
|
836 ngx_log_debug2(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
837 "resolver expire \"%*s\"", (size_t) rn->nlen, rn->name);
|
350
|
838
|
|
839 ngx_queue_remove(q);
|
|
840
|
|
841 ngx_rbtree_delete(tree, &rn->node);
|
|
842
|
|
843 ngx_resolver_free_node(r, rn);
|
|
844 }
|
|
845 }
|
|
846
|
|
847
|
|
848 static ngx_int_t
|
|
849 ngx_resolver_send_query(ngx_resolver_t *r, ngx_resolver_node_t *rn)
|
|
850 {
|
|
851 ssize_t n;
|
|
852 ngx_udp_connection_t *uc;
|
|
853
|
646
|
854 uc = r->udp_connections.elts;
|
|
855
|
|
856 uc = &uc[r->last_connection++];
|
|
857 if (r->last_connection == r->udp_connections.nelts) {
|
|
858 r->last_connection = 0;
|
|
859 }
|
350
|
860
|
|
861 if (uc->connection == NULL) {
|
|
862 if (ngx_udp_connect(uc) != NGX_OK) {
|
|
863 return NGX_ERROR;
|
|
864 }
|
|
865
|
|
866 uc->connection->data = r;
|
|
867 uc->connection->read->handler = ngx_resolver_read_response;
|
366
|
868 uc->connection->read->resolver = 1;
|
350
|
869 }
|
|
870
|
|
871 n = ngx_send(uc->connection, rn->query, rn->qlen);
|
|
872
|
|
873 if (n == -1) {
|
|
874 return NGX_ERROR;
|
|
875 }
|
|
876
|
|
877 if ((size_t) n != (size_t) rn->qlen) {
|
560
|
878 ngx_log_error(NGX_LOG_CRIT, &uc->log, 0, "send() incomplete");
|
350
|
879 return NGX_ERROR;
|
|
880 }
|
|
881
|
|
882 return NGX_OK;
|
|
883 }
|
|
884
|
|
885
|
|
886 static void
|
|
887 ngx_resolver_resend_handler(ngx_event_t *ev)
|
|
888 {
|
|
889 time_t timer, atimer, ntimer;
|
|
890 ngx_resolver_t *r;
|
|
891
|
|
892 r = ev->data;
|
|
893
|
|
894 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
895 "resolver resend handler");
|
|
896
|
|
897 /* lock name mutex */
|
|
898
|
|
899 ntimer = ngx_resolver_resend(r, &r->name_rbtree, &r->name_resend_queue);
|
|
900
|
|
901 /* unlock name mutex */
|
|
902
|
|
903 /* lock addr mutex */
|
|
904
|
|
905 atimer = ngx_resolver_resend(r, &r->addr_rbtree, &r->addr_resend_queue);
|
354
|
906
|
350
|
907 /* unlock addr mutex */
|
|
908
|
|
909 if (ntimer == 0) {
|
|
910 timer = atimer;
|
|
911
|
|
912 } else if (atimer == 0) {
|
|
913 timer = ntimer;
|
|
914
|
|
915 } else {
|
|
916 timer = (atimer < ntimer) ? atimer : ntimer;
|
|
917 }
|
|
918
|
|
919 if (timer) {
|
|
920 ngx_add_timer(r->event, (ngx_msec_t) (timer * 1000));
|
|
921 }
|
|
922 }
|
|
923
|
|
924
|
|
925 static time_t
|
|
926 ngx_resolver_resend(ngx_resolver_t *r, ngx_rbtree_t *tree, ngx_queue_t *queue)
|
|
927 {
|
|
928 time_t now;
|
|
929 ngx_queue_t *q;
|
|
930 ngx_resolver_node_t *rn;
|
|
931
|
|
932 now = ngx_time();
|
|
933
|
|
934 for ( ;; ) {
|
|
935 if (ngx_queue_empty(queue)) {
|
|
936 return 0;
|
|
937 }
|
|
938
|
|
939 q = ngx_queue_last(queue);
|
|
940
|
|
941 rn = ngx_queue_data(q, ngx_resolver_node_t, queue);
|
|
942
|
|
943 if (now < rn->expire) {
|
|
944 return rn->expire - now;
|
|
945 }
|
|
946
|
358
|
947 ngx_log_debug3(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
948 "resolver resend \"%*s\" %p",
|
|
949 (size_t) rn->nlen, rn->name, rn->waiting);
|
350
|
950
|
|
951 ngx_queue_remove(q);
|
|
952
|
|
953 if (rn->waiting) {
|
|
954
|
|
955 if (ngx_resolver_send_query(r, rn) == NGX_OK) {
|
|
956
|
|
957 rn->expire = now + r->resend_timeout;
|
|
958
|
|
959 ngx_queue_insert_head(queue, &rn->queue);
|
|
960 }
|
364
|
961
|
|
962 continue;
|
350
|
963 }
|
|
964
|
|
965 ngx_rbtree_delete(tree, &rn->node);
|
|
966
|
|
967 ngx_resolver_free_node(r, rn);
|
|
968 }
|
|
969 }
|
|
970
|
|
971
|
|
972 static void
|
|
973 ngx_resolver_read_response(ngx_event_t *rev)
|
|
974 {
|
|
975 ssize_t n;
|
|
976 ngx_connection_t *c;
|
|
977 u_char buf[NGX_RESOLVER_UDP_SIZE];
|
|
978
|
|
979 c = rev->data;
|
|
980
|
|
981 do {
|
354
|
982 n = ngx_udp_recv(c, buf, NGX_RESOLVER_UDP_SIZE);
|
|
983
|
|
984 if (n < 0) {
|
350
|
985 return;
|
|
986 }
|
|
987
|
|
988 ngx_resolver_process_response(c->data, buf, n);
|
|
989
|
|
990 } while (rev->ready);
|
|
991 }
|
|
992
|
|
993
|
|
994 static void
|
|
995 ngx_resolver_process_response(ngx_resolver_t *r, u_char *buf, size_t n)
|
|
996 {
|
|
997 char *err;
|
|
998 size_t len;
|
416
|
999 ngx_uint_t i, times, ident, qident, flags, code, nqs, nan,
|
|
1000 qtype, qclass;
|
|
1001 ngx_queue_t *q;
|
350
|
1002 ngx_resolver_qs_t *qs;
|
416
|
1003 ngx_resolver_node_t *rn;
|
350
|
1004 ngx_resolver_query_t *query;
|
|
1005
|
416
|
1006 if ((size_t) n < sizeof(ngx_resolver_query_t)) {
|
350
|
1007 goto short_response;
|
|
1008 }
|
|
1009
|
|
1010 query = (ngx_resolver_query_t *) buf;
|
|
1011
|
|
1012 ident = (query->ident_hi << 8) + query->ident_lo;
|
|
1013 flags = (query->flags_hi << 8) + query->flags_lo;
|
|
1014 nqs = (query->nqs_hi << 8) + query->nqs_lo;
|
|
1015 nan = (query->nan_hi << 8) + query->nan_lo;
|
|
1016
|
|
1017 ngx_log_debug6(NGX_LOG_DEBUG_CORE, r->log, 0,
|
372
|
1018 "resolver DNS response %ui fl:%04Xui %ui/%ui/%ui/%ui",
|
350
|
1019 ident, flags, nqs, nan,
|
|
1020 (query->nns_hi << 8) + query->nns_lo,
|
|
1021 (query->nar_hi << 8) + query->nar_lo);
|
|
1022
|
|
1023 if (!(flags & 0x8000)) {
|
|
1024 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1025 "invalid DNS response %ui fl:%04Xui", ident, flags);
|
350
|
1026 return;
|
|
1027 }
|
|
1028
|
|
1029 code = flags & 0x7f;
|
|
1030
|
416
|
1031 if (code == NGX_RESOLVE_FORMERR) {
|
|
1032
|
|
1033 times = 0;
|
|
1034
|
|
1035 for (q = ngx_queue_head(&r->name_resend_queue);
|
|
1036 q != ngx_queue_sentinel(&r->name_resend_queue) || times++ < 100;
|
|
1037 q = ngx_queue_next(q))
|
|
1038 {
|
|
1039 rn = ngx_queue_data(q, ngx_resolver_node_t, queue);
|
|
1040 qident = (rn->query[0] << 8) + rn->query[1];
|
|
1041
|
|
1042 if (qident == ident) {
|
|
1043 ngx_log_error(r->log_level, r->log, 0,
|
|
1044 "DNS error (%ui: %s), query id:%ui, name:\"%*s\"",
|
|
1045 code, ngx_resolver_strerror(code), ident,
|
|
1046 rn->nlen, rn->name);
|
|
1047 return;
|
|
1048 }
|
|
1049 }
|
|
1050
|
|
1051 goto dns_error;
|
|
1052 }
|
|
1053
|
|
1054 if (code > NGX_RESOLVE_REFUSED) {
|
|
1055 goto dns_error;
|
350
|
1056 }
|
|
1057
|
|
1058 if (nqs != 1) {
|
|
1059 err = "invalid number of questions in DNS response";
|
|
1060 goto done;
|
|
1061 }
|
|
1062
|
|
1063 i = sizeof(ngx_resolver_query_t);
|
|
1064
|
|
1065 while (i < (ngx_uint_t) n) {
|
|
1066 if (buf[i] == '\0') {
|
|
1067 goto found;
|
|
1068 }
|
|
1069
|
|
1070 len = buf[i];
|
|
1071 i += 1 + len;
|
|
1072 }
|
|
1073
|
|
1074 goto short_response;
|
|
1075
|
|
1076 found:
|
|
1077
|
|
1078 if (i++ == 0) {
|
|
1079 err = "zero-length domain name in DNS response";
|
|
1080 goto done;
|
|
1081 }
|
|
1082
|
|
1083 if (i + sizeof(ngx_resolver_qs_t) + nan * (2 + sizeof(ngx_resolver_an_t))
|
|
1084 > (ngx_uint_t) n)
|
|
1085 {
|
|
1086 goto short_response;
|
|
1087 }
|
|
1088
|
|
1089 qs = (ngx_resolver_qs_t *) &buf[i];
|
|
1090
|
|
1091 qtype = (qs->type_hi << 8) + qs->type_lo;
|
|
1092 qclass = (qs->class_hi << 8) + qs->class_lo;
|
|
1093
|
|
1094 ngx_log_debug2(NGX_LOG_DEBUG_CORE, r->log, 0,
|
372
|
1095 "resolver DNS response qt:%ui cl:%ui", qtype, qclass);
|
350
|
1096
|
|
1097 if (qclass != 1) {
|
|
1098 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1099 "unknown query class %ui in DNS response", qclass);
|
350
|
1100 return;
|
|
1101 }
|
|
1102
|
|
1103 switch (qtype) {
|
|
1104
|
|
1105 case NGX_RESOLVE_A:
|
|
1106
|
|
1107 ngx_resolver_process_a(r, buf, n, ident, code, nan,
|
356
|
1108 i + sizeof(ngx_resolver_qs_t));
|
350
|
1109
|
|
1110 break;
|
|
1111
|
|
1112 case NGX_RESOLVE_PTR:
|
|
1113
|
356
|
1114 ngx_resolver_process_ptr(r, buf, n, ident, code, nan);
|
350
|
1115
|
|
1116 break;
|
|
1117
|
|
1118 default:
|
|
1119 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1120 "unknown query type %ui in DNS response", qtype);
|
350
|
1121 return;
|
|
1122 }
|
|
1123
|
|
1124 return;
|
|
1125
|
|
1126 short_response:
|
|
1127
|
|
1128 err = "short dns response";
|
|
1129
|
|
1130 done:
|
|
1131
|
|
1132 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1133
|
|
1134 return;
|
416
|
1135
|
|
1136 dns_error:
|
|
1137
|
|
1138 ngx_log_error(r->log_level, r->log, 0,
|
|
1139 "DNS error (%ui: %s), query id:%ui",
|
|
1140 code, ngx_resolver_strerror(code), ident);
|
|
1141 return;
|
350
|
1142 }
|
|
1143
|
|
1144
|
|
1145 static void
|
|
1146 ngx_resolver_process_a(ngx_resolver_t *r, u_char *buf, size_t last,
|
|
1147 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan, ngx_uint_t ans)
|
|
1148 {
|
|
1149 char *err;
|
|
1150 u_char *cname;
|
|
1151 size_t len;
|
|
1152 uint32_t hash;
|
|
1153 in_addr_t addr, *addrs;
|
|
1154 ngx_str_t name;
|
|
1155 ngx_uint_t qtype, qident, naddrs, a, i, n, start;
|
|
1156 ngx_resolver_an_t *an;
|
|
1157 ngx_resolver_ctx_t *ctx, *next;
|
|
1158 ngx_resolver_node_t *rn;
|
|
1159
|
|
1160 if (ngx_resolver_copy(r, &name, buf, &buf[12], &buf[last]) != NGX_OK) {
|
|
1161 return;
|
|
1162 }
|
|
1163
|
|
1164 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver qs:%V", &name);
|
|
1165
|
|
1166 hash = ngx_crc32_short(name.data, name.len);
|
|
1167
|
|
1168 /* lock name mutex */
|
|
1169
|
|
1170 rn = ngx_resolver_lookup_name(r, &name, hash);
|
|
1171
|
|
1172 if (rn == NULL || rn->query == NULL) {
|
|
1173 ngx_log_error(r->log_level, r->log, 0,
|
|
1174 "unexpected response for %V", &name);
|
|
1175 goto failed;
|
|
1176 }
|
|
1177
|
|
1178 qident = (rn->query[0] << 8) + rn->query[1];
|
|
1179
|
|
1180 if (ident != qident) {
|
|
1181 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1182 "wrong ident %ui response for %V, expect %ui",
|
350
|
1183 ident, &name, qident);
|
|
1184 goto failed;
|
|
1185 }
|
|
1186
|
528
|
1187 ngx_resolver_free(r, name.data);
|
|
1188
|
356
|
1189 if (code == 0 && nan == 0) {
|
|
1190 code = 3; /* NXDOMAIN */
|
|
1191 }
|
|
1192
|
350
|
1193 if (code) {
|
|
1194 next = rn->waiting;
|
|
1195 rn->waiting = NULL;
|
|
1196
|
|
1197 ngx_queue_remove(&rn->queue);
|
|
1198
|
|
1199 ngx_rbtree_delete(&r->name_rbtree, &rn->node);
|
|
1200
|
|
1201 ngx_resolver_free_node(r, rn);
|
|
1202
|
|
1203 /* unlock name mutex */
|
|
1204
|
|
1205 while (next) {
|
|
1206 ctx = next;
|
|
1207 ctx->state = code;
|
|
1208 next = ctx->next;
|
|
1209
|
|
1210 ctx->handler(ctx);
|
|
1211 }
|
|
1212
|
|
1213 return;
|
|
1214 }
|
|
1215
|
|
1216 i = ans;
|
|
1217 naddrs = 0;
|
|
1218 addr = 0;
|
|
1219 addrs = NULL;
|
|
1220 cname = NULL;
|
|
1221 qtype = 0;
|
|
1222
|
|
1223 for (a = 0; a < nan; a++) {
|
|
1224
|
|
1225 start = i;
|
|
1226
|
|
1227 while (i < last) {
|
|
1228
|
|
1229 if (buf[i] & 0xc0) {
|
|
1230 i += 2;
|
|
1231 goto found;
|
|
1232 }
|
|
1233
|
|
1234 if (buf[i] == 0) {
|
|
1235 i++;
|
|
1236 goto test_length;
|
|
1237 }
|
|
1238
|
|
1239 i += 1 + buf[i];
|
|
1240 }
|
|
1241
|
|
1242 goto short_response;
|
|
1243
|
|
1244 test_length:
|
|
1245
|
|
1246 if (i - start < 2) {
|
|
1247 err = "invalid name in dns response";
|
|
1248 goto invalid;
|
|
1249 }
|
|
1250
|
|
1251 found:
|
|
1252
|
|
1253 if (i + sizeof(ngx_resolver_an_t) >= last) {
|
|
1254 goto short_response;
|
|
1255 }
|
|
1256
|
|
1257 an = (ngx_resolver_an_t *) &buf[i];
|
|
1258
|
|
1259 qtype = (an->type_hi << 8) + an->type_lo;
|
|
1260 len = (an->len_hi << 8) + an->len_lo;
|
|
1261
|
|
1262 if (qtype == NGX_RESOLVE_A) {
|
|
1263
|
|
1264 i += sizeof(ngx_resolver_an_t);
|
|
1265
|
|
1266 if (i + len > last) {
|
|
1267 goto short_response;
|
|
1268 }
|
|
1269
|
|
1270 addr = htonl((buf[i] << 24) + (buf[i + 1] << 16)
|
|
1271 + (buf[i + 2] << 8) + (buf[i + 3]));
|
|
1272
|
|
1273 naddrs++;
|
|
1274
|
|
1275 i += len;
|
|
1276
|
|
1277 } else if (qtype == NGX_RESOLVE_CNAME) {
|
|
1278 cname = &buf[i] + sizeof(ngx_resolver_an_t);
|
|
1279 i += sizeof(ngx_resolver_an_t) + len;
|
372
|
1280
|
|
1281 } else if (qtype == NGX_RESOLVE_DNAME) {
|
|
1282 i += sizeof(ngx_resolver_an_t) + len;
|
|
1283
|
|
1284 } else {
|
|
1285 ngx_log_error(r->log_level, r->log, 0,
|
|
1286 "unexpected qtype %ui", qtype);
|
350
|
1287 }
|
|
1288 }
|
|
1289
|
|
1290 ngx_log_debug2(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
1291 "resolver naddrs:%ui cname:%p", naddrs, cname);
|
|
1292
|
|
1293 if (naddrs) {
|
|
1294
|
|
1295 if (naddrs == 1) {
|
|
1296 rn->u.addr = addr;
|
|
1297
|
|
1298 } else {
|
|
1299
|
|
1300 addrs = ngx_resolver_alloc(r, naddrs * sizeof(in_addr_t));
|
|
1301 if (addrs == NULL) {
|
|
1302 return;
|
|
1303 }
|
|
1304
|
|
1305 n = 0;
|
|
1306 i = ans;
|
|
1307
|
|
1308 for (a = 0; a < nan; a++) {
|
|
1309
|
|
1310 for ( ;; ) {
|
|
1311
|
|
1312 if (buf[i] & 0xc0) {
|
|
1313 i += 2;
|
|
1314 goto ok;
|
|
1315 }
|
|
1316
|
|
1317 if (buf[i] == 0) {
|
|
1318 i++;
|
|
1319 goto ok;
|
|
1320 }
|
|
1321
|
|
1322 i += 1 + buf[i];
|
|
1323 }
|
|
1324
|
|
1325 ok:
|
|
1326
|
|
1327 an = (ngx_resolver_an_t *) &buf[i];
|
|
1328
|
|
1329 qtype = (an->type_hi << 8) + an->type_lo;
|
|
1330 len = (an->len_hi << 8) + an->len_lo;
|
|
1331
|
|
1332 i += sizeof(ngx_resolver_an_t);
|
|
1333
|
|
1334 if (qtype == NGX_RESOLVE_A) {
|
|
1335
|
|
1336 addrs[n++] = htonl((buf[i] << 24) + (buf[i + 1] << 16)
|
|
1337 + (buf[i + 2] << 8) + (buf[i + 3]));
|
|
1338
|
|
1339 if (n == naddrs) {
|
|
1340 break;
|
|
1341 }
|
|
1342 }
|
|
1343
|
|
1344 i += len;
|
|
1345 }
|
|
1346
|
|
1347 rn->u.addrs = addrs;
|
|
1348
|
|
1349 addrs = ngx_resolver_dup(r, rn->u.addrs,
|
|
1350 naddrs * sizeof(in_addr_t));
|
|
1351 if (addrs == NULL) {
|
|
1352 return;
|
|
1353 }
|
|
1354 }
|
|
1355
|
|
1356 rn->naddrs = (u_short) naddrs;
|
|
1357
|
|
1358 ngx_queue_remove(&rn->queue);
|
|
1359
|
|
1360 rn->valid = ngx_time() + r->valid;
|
|
1361 rn->expire = ngx_time() + r->expire;
|
|
1362
|
|
1363 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue);
|
|
1364
|
|
1365 next = rn->waiting;
|
|
1366 rn->waiting = NULL;
|
|
1367
|
|
1368 /* unlock name mutex */
|
|
1369
|
|
1370 while (next) {
|
|
1371 ctx = next;
|
|
1372 ctx->state = NGX_OK;
|
|
1373 ctx->naddrs = naddrs;
|
|
1374 ctx->addrs = (naddrs == 1) ? &ctx->addr : addrs;
|
|
1375 ctx->addr = addr;
|
|
1376 next = ctx->next;
|
|
1377
|
|
1378 ctx->handler(ctx);
|
|
1379 }
|
|
1380
|
442
|
1381 if (naddrs > 1) {
|
350
|
1382 ngx_resolver_free(r, addrs);
|
|
1383 }
|
|
1384
|
|
1385 return;
|
|
1386
|
|
1387 } else if (cname) {
|
|
1388
|
|
1389 /* CNAME only */
|
|
1390
|
|
1391 if (ngx_resolver_copy(r, &name, buf, cname, &buf[last]) != NGX_OK) {
|
|
1392 return;
|
|
1393 }
|
|
1394
|
|
1395 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
1396 "resolver cname:\"%V\"", &name);
|
|
1397
|
356
|
1398 ngx_queue_remove(&rn->queue);
|
|
1399
|
350
|
1400 rn->cnlen = (u_short) name.len;
|
|
1401 rn->u.cname = name.data;
|
|
1402 rn->valid = ngx_time() + r->valid;
|
|
1403 rn->expire = ngx_time() + r->expire;
|
|
1404
|
|
1405 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue);
|
|
1406
|
|
1407 ctx = rn->waiting;
|
|
1408 rn->waiting = NULL;
|
|
1409
|
|
1410 if (ctx) {
|
|
1411 ctx->name = name;
|
|
1412
|
|
1413 (void) ngx_resolve_name_locked(r, ctx);
|
|
1414 }
|
|
1415
|
|
1416 return;
|
|
1417 }
|
|
1418
|
|
1419 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1420 "no A or CNAME types in DNS responses, unknown query type: %ui",
|
|
1421 qtype);
|
350
|
1422 return;
|
|
1423
|
|
1424 short_response:
|
|
1425
|
|
1426 err = "short dns response";
|
|
1427
|
|
1428 invalid:
|
|
1429
|
|
1430 /* unlock name mutex */
|
|
1431
|
|
1432 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1433
|
|
1434 return;
|
|
1435
|
|
1436 failed:
|
|
1437
|
|
1438 /* unlock name mutex */
|
|
1439
|
528
|
1440 ngx_resolver_free(r, name.data);
|
|
1441
|
350
|
1442 return;
|
|
1443 }
|
|
1444
|
|
1445
|
|
1446 static void
|
|
1447 ngx_resolver_process_ptr(ngx_resolver_t *r, u_char *buf, size_t n,
|
356
|
1448 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan)
|
350
|
1449 {
|
|
1450 char *err;
|
|
1451 size_t len;
|
|
1452 in_addr_t addr;
|
|
1453 ngx_int_t digit;
|
|
1454 ngx_str_t name;
|
622
|
1455 ngx_uint_t i, mask, qident;
|
350
|
1456 ngx_resolver_an_t *an;
|
|
1457 ngx_resolver_ctx_t *ctx, *next;
|
|
1458 ngx_resolver_node_t *rn;
|
|
1459
|
|
1460 if (ngx_resolver_copy(r, NULL, buf, &buf[12], &buf[n]) != NGX_OK) {
|
|
1461 goto invalid_in_addr_arpa;
|
|
1462 }
|
|
1463
|
|
1464 addr = 0;
|
|
1465 i = 12;
|
|
1466
|
|
1467 for (mask = 0; mask < 32; mask += 8) {
|
|
1468 len = buf[i++];
|
|
1469
|
|
1470 digit = ngx_atoi(&buf[i], len);
|
|
1471 if (digit == NGX_ERROR || digit > 255) {
|
|
1472 goto invalid_in_addr_arpa;
|
|
1473 }
|
|
1474
|
|
1475 addr += digit << mask;
|
|
1476 i += len;
|
|
1477 }
|
|
1478
|
|
1479 if (ngx_strcmp(&buf[i], "\7in-addr\4arpa") != 0) {
|
|
1480 goto invalid_in_addr_arpa;
|
|
1481 }
|
|
1482
|
|
1483 /* lock addr mutex */
|
|
1484
|
|
1485 rn = ngx_resolver_lookup_addr(r, addr);
|
|
1486
|
|
1487 if (rn == NULL || rn->query == NULL) {
|
|
1488 ngx_log_error(r->log_level, r->log, 0,
|
|
1489 "unexpected response for %ud.%ud.%ud.%ud",
|
|
1490 (addr >> 24) & 0xff, (addr >> 16) & 0xff,
|
|
1491 (addr >> 8) & 0xff, addr & 0xff);
|
|
1492 goto failed;
|
|
1493 }
|
|
1494
|
|
1495 qident = (rn->query[0] << 8) + rn->query[1];
|
|
1496
|
|
1497 if (ident != qident) {
|
|
1498 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1499 "wrong ident %ui response for %ud.%ud.%ud.%ud, expect %ui",
|
|
1500 ident, (addr >> 24) & 0xff, (addr >> 16) & 0xff,
|
|
1501 (addr >> 8) & 0xff, addr & 0xff, qident);
|
350
|
1502 goto failed;
|
|
1503 }
|
|
1504
|
356
|
1505 if (code == 0 && nan == 0) {
|
|
1506 code = 3; /* NXDOMAIN */
|
|
1507 }
|
|
1508
|
350
|
1509 if (code) {
|
|
1510 next = rn->waiting;
|
|
1511 rn->waiting = NULL;
|
|
1512
|
|
1513 ngx_queue_remove(&rn->queue);
|
|
1514
|
|
1515 ngx_rbtree_delete(&r->addr_rbtree, &rn->node);
|
|
1516
|
|
1517 ngx_resolver_free_node(r, rn);
|
|
1518
|
|
1519 /* unlock addr mutex */
|
|
1520
|
|
1521 while (next) {
|
|
1522 ctx = next;
|
|
1523 ctx->state = code;
|
|
1524 next = ctx->next;
|
|
1525
|
|
1526 ctx->handler(ctx);
|
|
1527 }
|
|
1528
|
|
1529 return;
|
|
1530 }
|
|
1531
|
|
1532 i += sizeof("\7in-addr\4arpa") + sizeof(ngx_resolver_qs_t);
|
|
1533
|
|
1534 if (i + 2 + sizeof(ngx_resolver_an_t) > (ngx_uint_t) n) {
|
|
1535 goto short_response;
|
|
1536 }
|
|
1537
|
|
1538 /* compression pointer to "XX.XX.XX.XX.in-addr.arpa */
|
|
1539
|
|
1540 if (buf[i] != 0xc0 || buf[i + 1] != 0x0c) {
|
|
1541 err = "invalid in-addr.arpa name in DNS response";
|
|
1542 goto invalid;
|
|
1543 }
|
|
1544
|
|
1545 an = (ngx_resolver_an_t *) &buf[i + 2];
|
|
1546
|
|
1547 len = (an->len_hi << 8) + an->len_lo;
|
|
1548
|
|
1549 ngx_log_debug3(NGX_LOG_DEBUG_CORE, r->log, 0,
|
622
|
1550 "resolver qt:%ui cl:%ui len:%uz",
|
|
1551 (an->type_hi << 8) + an->type_lo,
|
|
1552 (an->class_hi << 8) + an->class_lo, len);
|
350
|
1553
|
|
1554 i += 2 + sizeof(ngx_resolver_an_t);
|
|
1555
|
|
1556 if (i + len > (ngx_uint_t) n) {
|
|
1557 goto short_response;
|
|
1558 }
|
|
1559
|
|
1560 if (ngx_resolver_copy(r, &name, buf, &buf[i], &buf[n]) != NGX_OK) {
|
|
1561 return;
|
|
1562 }
|
|
1563
|
|
1564 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver an:%V", &name);
|
|
1565
|
442
|
1566 if (name.len != (size_t) rn->nlen
|
|
1567 || ngx_strncmp(name.data, rn->name, name.len) != 0)
|
350
|
1568 {
|
442
|
1569 if (rn->nlen) {
|
|
1570 ngx_resolver_free(r, rn->name);
|
|
1571 }
|
|
1572
|
|
1573 rn->nlen = (u_short) name.len;
|
350
|
1574 rn->name = name.data;
|
|
1575
|
442
|
1576 name.data = ngx_resolver_dup(r, rn->name, name.len);
|
350
|
1577 if (name.data == NULL) {
|
|
1578 goto failed;
|
|
1579 }
|
|
1580 }
|
|
1581
|
|
1582 ngx_queue_remove(&rn->queue);
|
|
1583
|
|
1584 rn->valid = ngx_time() + r->valid;
|
|
1585 rn->expire = ngx_time() + r->expire;
|
|
1586
|
|
1587 ngx_queue_insert_head(&r->addr_expire_queue, &rn->queue);
|
|
1588
|
|
1589 next = rn->waiting;
|
|
1590 rn->waiting = NULL;
|
|
1591
|
|
1592 /* unlock addr mutex */
|
|
1593
|
|
1594 while (next) {
|
|
1595 ctx = next;
|
|
1596 ctx->state = NGX_OK;
|
|
1597 ctx->name = name;
|
|
1598 next = ctx->next;
|
|
1599
|
|
1600 ctx->handler(ctx);
|
|
1601 }
|
|
1602
|
|
1603 ngx_resolver_free(r, name.data);
|
|
1604
|
|
1605 return;
|
|
1606
|
|
1607 invalid_in_addr_arpa:
|
|
1608
|
|
1609 ngx_log_error(r->log_level, r->log, 0,
|
|
1610 "invalid in-addr.arpa name in DNS response");
|
|
1611 return;
|
|
1612
|
|
1613 short_response:
|
|
1614
|
|
1615 err = "short DNS response";
|
|
1616
|
|
1617 invalid:
|
|
1618
|
|
1619 /* unlock addr mutex */
|
|
1620
|
|
1621 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1622
|
|
1623 return;
|
|
1624
|
|
1625 failed:
|
|
1626
|
|
1627 /* unlock addr mutex */
|
|
1628
|
|
1629 return;
|
|
1630 }
|
|
1631
|
|
1632
|
|
1633 static ngx_resolver_node_t *
|
|
1634 ngx_resolver_lookup_name(ngx_resolver_t *r, ngx_str_t *name, uint32_t hash)
|
|
1635 {
|
|
1636 ngx_int_t rc;
|
|
1637 ngx_rbtree_node_t *node, *sentinel;
|
|
1638 ngx_resolver_node_t *rn;
|
|
1639
|
|
1640 node = r->name_rbtree.root;
|
|
1641 sentinel = r->name_rbtree.sentinel;
|
|
1642
|
|
1643 while (node != sentinel) {
|
|
1644
|
|
1645 if (hash < node->key) {
|
|
1646 node = node->left;
|
|
1647 continue;
|
|
1648 }
|
|
1649
|
|
1650 if (hash > node->key) {
|
|
1651 node = node->right;
|
|
1652 continue;
|
|
1653 }
|
|
1654
|
|
1655 /* hash == node->key */
|
|
1656
|
|
1657 do {
|
|
1658 rn = (ngx_resolver_node_t *) node;
|
|
1659
|
528
|
1660 rc = ngx_memn2cmp(name->data, rn->name, name->len, rn->nlen);
|
350
|
1661
|
|
1662 if (rc == 0) {
|
|
1663 return rn;
|
|
1664 }
|
|
1665
|
|
1666 node = (rc < 0) ? node->left : node->right;
|
|
1667
|
|
1668 } while (node != sentinel && hash == node->key);
|
|
1669
|
|
1670 break;
|
|
1671 }
|
|
1672
|
|
1673 /* not found */
|
|
1674
|
|
1675 return NULL;
|
|
1676 }
|
|
1677
|
|
1678
|
|
1679 static ngx_resolver_node_t *
|
|
1680 ngx_resolver_lookup_addr(ngx_resolver_t *r, in_addr_t addr)
|
|
1681 {
|
|
1682 ngx_rbtree_node_t *node, *sentinel;
|
|
1683
|
|
1684 node = r->addr_rbtree.root;
|
|
1685 sentinel = r->addr_rbtree.sentinel;
|
|
1686
|
|
1687 while (node != sentinel) {
|
|
1688
|
|
1689 if (addr < node->key) {
|
|
1690 node = node->left;
|
|
1691 continue;
|
|
1692 }
|
|
1693
|
|
1694 if (addr > node->key) {
|
|
1695 node = node->right;
|
|
1696 continue;
|
|
1697 }
|
|
1698
|
|
1699 /* addr == node->key */
|
|
1700
|
|
1701 return (ngx_resolver_node_t *) node;
|
|
1702 }
|
|
1703
|
|
1704 /* not found */
|
|
1705
|
|
1706 return NULL;
|
|
1707 }
|
|
1708
|
|
1709
|
|
1710 static void
|
|
1711 ngx_resolver_rbtree_insert_value(ngx_rbtree_node_t *temp,
|
|
1712 ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel)
|
|
1713 {
|
|
1714 ngx_rbtree_node_t **p;
|
|
1715 ngx_resolver_node_t *rn, *rn_temp;
|
|
1716
|
|
1717 for ( ;; ) {
|
|
1718
|
|
1719 if (node->key < temp->key) {
|
|
1720
|
|
1721 p = &temp->left;
|
|
1722
|
|
1723 } else if (node->key > temp->key) {
|
|
1724
|
|
1725 p = &temp->right;
|
|
1726
|
|
1727 } else { /* node->key == temp->key */
|
|
1728
|
|
1729 rn = (ngx_resolver_node_t *) node;
|
|
1730 rn_temp = (ngx_resolver_node_t *) temp;
|
|
1731
|
528
|
1732 p = (ngx_memn2cmp(rn->name, rn_temp->name, rn->nlen, rn_temp->nlen)
|
|
1733 < 0) ? &temp->left : &temp->right;
|
350
|
1734 }
|
|
1735
|
|
1736 if (*p == sentinel) {
|
|
1737 break;
|
|
1738 }
|
|
1739
|
|
1740 temp = *p;
|
|
1741 }
|
|
1742
|
|
1743 *p = node;
|
|
1744 node->parent = temp;
|
|
1745 node->left = sentinel;
|
|
1746 node->right = sentinel;
|
|
1747 ngx_rbt_red(node);
|
|
1748 }
|
|
1749
|
|
1750
|
|
1751 static ngx_int_t
|
|
1752 ngx_resolver_create_name_query(ngx_resolver_node_t *rn, ngx_resolver_ctx_t *ctx)
|
|
1753 {
|
|
1754 u_char *p, *s;
|
544
|
1755 size_t len, nlen;
|
350
|
1756 ngx_uint_t ident;
|
|
1757 ngx_resolver_qs_t *qs;
|
|
1758 ngx_resolver_query_t *query;
|
|
1759
|
544
|
1760 nlen = ctx->name.len ? (1 + ctx->name.len + 1) : 1;
|
|
1761
|
|
1762 len = sizeof(ngx_resolver_query_t) + nlen + sizeof(ngx_resolver_qs_t);
|
|
1763
|
|
1764 p = ngx_resolver_alloc(ctx->resolver, len);
|
350
|
1765 if (p == NULL) {
|
|
1766 return NGX_ERROR;
|
|
1767 }
|
|
1768
|
|
1769 rn->qlen = (u_short) len;
|
|
1770 rn->query = p;
|
|
1771
|
|
1772 query = (ngx_resolver_query_t *) p;
|
|
1773
|
|
1774 ident = ngx_random();
|
|
1775
|
|
1776 ngx_log_debug2(NGX_LOG_DEBUG_CORE, ctx->resolver->log, 0,
|
|
1777 "resolve: \"%V\" %i", &ctx->name, ident & 0xffff);
|
|
1778
|
|
1779 query->ident_hi = (u_char) ((ident >> 8) & 0xff);
|
|
1780 query->ident_lo = (u_char) (ident & 0xff);
|
|
1781
|
|
1782 /* recursion query */
|
|
1783 query->flags_hi = 1; query->flags_lo = 0;
|
|
1784
|
|
1785 /* one question */
|
|
1786 query->nqs_hi = 0; query->nqs_lo = 1;
|
|
1787 query->nan_hi = 0; query->nan_lo = 0;
|
|
1788 query->nns_hi = 0; query->nns_lo = 0;
|
|
1789 query->nar_hi = 0; query->nar_lo = 0;
|
|
1790
|
544
|
1791 p += sizeof(ngx_resolver_query_t) + nlen;
|
350
|
1792
|
|
1793 qs = (ngx_resolver_qs_t *) p;
|
|
1794
|
|
1795 /* query type */
|
|
1796 qs->type_hi = 0; qs->type_lo = (u_char) ctx->type;
|
|
1797
|
|
1798 /* IP query class */
|
|
1799 qs->class_hi = 0; qs->class_lo = 1;
|
|
1800
|
|
1801 /* convert "www.example.com" to "\3www\7example\3com\0" */
|
|
1802
|
|
1803 len = 0;
|
|
1804 p--;
|
|
1805 *p-- = '\0';
|
|
1806
|
|
1807 for (s = ctx->name.data + ctx->name.len - 1; s >= ctx->name.data; s--) {
|
|
1808 if (*s != '.') {
|
|
1809 *p = *s;
|
|
1810 len++;
|
|
1811
|
|
1812 } else {
|
372
|
1813 if (len == 0) {
|
|
1814 return NGX_DECLINED;
|
|
1815 }
|
|
1816
|
350
|
1817 *p = (u_char) len;
|
|
1818 len = 0;
|
|
1819 }
|
|
1820
|
|
1821 p--;
|
|
1822 }
|
|
1823
|
|
1824 *p = (u_char) len;
|
|
1825
|
|
1826 return NGX_OK;
|
|
1827 }
|
|
1828
|
|
1829
|
|
1830 /* AF_INET only */
|
|
1831
|
|
1832 static ngx_int_t
|
|
1833 ngx_resolver_create_addr_query(ngx_resolver_node_t *rn, ngx_resolver_ctx_t *ctx)
|
|
1834 {
|
|
1835 u_char *p, *d;
|
|
1836 size_t len;
|
|
1837 ngx_int_t n;
|
|
1838 ngx_uint_t ident;
|
|
1839 ngx_resolver_query_t *query;
|
|
1840
|
|
1841 len = sizeof(ngx_resolver_query_t)
|
|
1842 + sizeof(".255.255.255.255.in-addr.arpa.") - 1
|
|
1843 + sizeof(ngx_resolver_qs_t);
|
|
1844
|
544
|
1845 p = ngx_resolver_alloc(ctx->resolver, len);
|
350
|
1846 if (p == NULL) {
|
|
1847 return NGX_ERROR;
|
|
1848 }
|
|
1849
|
|
1850 rn->query = p;
|
|
1851 query = (ngx_resolver_query_t *) p;
|
|
1852
|
|
1853 ident = ngx_random();
|
|
1854
|
|
1855 query->ident_hi = (u_char) ((ident >> 8) & 0xff);
|
|
1856 query->ident_lo = (u_char) (ident & 0xff);
|
|
1857
|
|
1858 /* recursion query */
|
|
1859 query->flags_hi = 1; query->flags_lo = 0;
|
|
1860
|
|
1861 /* one question */
|
|
1862 query->nqs_hi = 0; query->nqs_lo = 1;
|
|
1863 query->nan_hi = 0; query->nan_lo = 0;
|
|
1864 query->nns_hi = 0; query->nns_lo = 0;
|
|
1865 query->nar_hi = 0; query->nar_lo = 0;
|
|
1866
|
|
1867 p += sizeof(ngx_resolver_query_t);
|
|
1868
|
582
|
1869 for (n = 0; n < 32; n += 8) {
|
350
|
1870 d = ngx_sprintf(&p[1], "%ud", (ctx->addr >> n) & 0xff);
|
|
1871 *p = (u_char) (d - &p[1]);
|
|
1872 p = d;
|
|
1873 }
|
|
1874
|
|
1875 /* query type "PTR", IP query class */
|
|
1876 ngx_memcpy(p, "\7in-addr\4arpa\0\0\14\0\1", 18);
|
|
1877
|
|
1878 rn->qlen = (u_short)
|
|
1879 (p + sizeof("\7in-addr\4arpa") + sizeof(ngx_resolver_qs_t)
|
|
1880 - rn->query);
|
|
1881
|
|
1882 return NGX_OK;
|
|
1883 }
|
|
1884
|
|
1885
|
|
1886 static ngx_int_t
|
|
1887 ngx_resolver_copy(ngx_resolver_t *r, ngx_str_t *name, u_char *buf, u_char *src,
|
|
1888 u_char *last)
|
|
1889 {
|
|
1890 char *err;
|
|
1891 u_char *p, *dst;
|
|
1892 ssize_t len;
|
|
1893 ngx_uint_t i, n;
|
|
1894
|
|
1895 p = src;
|
|
1896 len = -1;
|
|
1897
|
|
1898 /*
|
|
1899 * compression pointers allow to create endless loop, so we set limit;
|
|
1900 * 128 pointers should be enough to store 255-byte name
|
|
1901 */
|
|
1902
|
|
1903 for (i = 0; i < 128; i++) {
|
|
1904 n = *p++;
|
|
1905
|
|
1906 if (n == 0) {
|
|
1907 goto done;
|
|
1908 }
|
|
1909
|
|
1910 if (n & 0xc0) {
|
420
|
1911 n = ((n & 0x3f) << 8) + *p;
|
350
|
1912 p = &buf[n];
|
|
1913
|
|
1914 } else {
|
|
1915 len += 1 + n;
|
|
1916 p = &p[n];
|
|
1917 }
|
|
1918
|
|
1919 if (p >= last) {
|
|
1920 err = "name is out of response";
|
|
1921 goto invalid;
|
|
1922 }
|
|
1923 }
|
|
1924
|
|
1925 err = "compression pointers loop";
|
|
1926
|
|
1927 invalid:
|
|
1928
|
|
1929 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1930
|
|
1931 return NGX_ERROR;
|
|
1932
|
|
1933 done:
|
|
1934
|
|
1935 if (name == NULL) {
|
|
1936 return NGX_OK;
|
|
1937 }
|
|
1938
|
542
|
1939 if (len == -1) {
|
|
1940 name->len = 0;
|
|
1941 name->data = NULL;
|
|
1942 return NGX_OK;
|
|
1943 }
|
|
1944
|
350
|
1945 dst = ngx_resolver_alloc(r, len);
|
|
1946 if (dst == NULL) {
|
|
1947 return NGX_ERROR;
|
|
1948 }
|
|
1949
|
|
1950 name->data = dst;
|
|
1951
|
|
1952 n = *src++;
|
|
1953
|
|
1954 for ( ;; ) {
|
648
|
1955 if (n & 0xc0) {
|
|
1956 n = ((n & 0x3f) << 8) + *src;
|
|
1957 src = &buf[n];
|
|
1958
|
|
1959 n = *src++;
|
|
1960
|
|
1961 } else {
|
350
|
1962 ngx_memcpy(dst, src, n);
|
|
1963 dst += n;
|
|
1964 src += n;
|
|
1965
|
|
1966 n = *src++;
|
|
1967
|
|
1968 if (n != 0) {
|
|
1969 *dst++ = '.';
|
|
1970 }
|
|
1971 }
|
|
1972
|
|
1973 if (n == 0) {
|
|
1974 name->len = dst - name->data;
|
|
1975 return NGX_OK;
|
|
1976 }
|
|
1977 }
|
|
1978 }
|
|
1979
|
|
1980
|
|
1981 static void
|
|
1982 ngx_resolver_timeout_handler(ngx_event_t *ev)
|
|
1983 {
|
|
1984 ngx_resolver_ctx_t *ctx;
|
|
1985
|
|
1986 ctx = ev->data;
|
|
1987
|
|
1988 ctx->state = NGX_RESOLVE_TIMEDOUT;
|
|
1989
|
|
1990 ctx->handler(ctx);
|
|
1991 }
|
|
1992
|
|
1993
|
|
1994 static void
|
|
1995 ngx_resolver_free_node(ngx_resolver_t *r, ngx_resolver_node_t *rn)
|
|
1996 {
|
|
1997 /* lock alloc mutex */
|
|
1998
|
|
1999 if (rn->query) {
|
|
2000 ngx_resolver_free_locked(r, rn->query);
|
|
2001 }
|
|
2002
|
|
2003 if (rn->name) {
|
|
2004 ngx_resolver_free_locked(r, rn->name);
|
|
2005 }
|
|
2006
|
|
2007 if (rn->cnlen) {
|
|
2008 ngx_resolver_free_locked(r, rn->u.cname);
|
|
2009 }
|
|
2010
|
|
2011 if (rn->naddrs > 1) {
|
|
2012 ngx_resolver_free_locked(r, rn->u.addrs);
|
|
2013 }
|
|
2014
|
|
2015 ngx_resolver_free_locked(r, rn);
|
|
2016
|
|
2017 /* unlock alloc mutex */
|
|
2018 }
|
|
2019
|
|
2020
|
|
2021 static void *
|
|
2022 ngx_resolver_alloc(ngx_resolver_t *r, size_t size)
|
|
2023 {
|
|
2024 u_char *p;
|
|
2025
|
|
2026 /* lock alloc mutex */
|
|
2027
|
|
2028 p = ngx_alloc(size, r->log);
|
|
2029
|
|
2030 /* unlock alloc mutex */
|
|
2031
|
|
2032 return p;
|
|
2033 }
|
|
2034
|
|
2035
|
366
|
2036 static void *
|
350
|
2037 ngx_resolver_calloc(ngx_resolver_t *r, size_t size)
|
|
2038 {
|
|
2039 u_char *p;
|
|
2040
|
|
2041 p = ngx_resolver_alloc(r, size);
|
|
2042
|
|
2043 if (p) {
|
|
2044 ngx_memzero(p, size);
|
|
2045 }
|
|
2046
|
|
2047 return p;
|
|
2048 }
|
|
2049
|
|
2050
|
|
2051 static void
|
|
2052 ngx_resolver_free(ngx_resolver_t *r, void *p)
|
|
2053 {
|
|
2054 /* lock alloc mutex */
|
|
2055
|
|
2056 ngx_free(p);
|
|
2057
|
|
2058 /* unlock alloc mutex */
|
|
2059 }
|
|
2060
|
|
2061
|
|
2062 static void
|
|
2063 ngx_resolver_free_locked(ngx_resolver_t *r, void *p)
|
|
2064 {
|
|
2065 ngx_free(p);
|
|
2066 }
|
|
2067
|
|
2068
|
|
2069 static void *
|
|
2070 ngx_resolver_dup(ngx_resolver_t *r, void *src, size_t size)
|
|
2071 {
|
|
2072 void *dst;
|
|
2073
|
|
2074 dst = ngx_resolver_alloc(r, size);
|
|
2075
|
|
2076 if (dst == NULL) {
|
|
2077 return dst;
|
|
2078 }
|
|
2079
|
|
2080 ngx_memcpy(dst, src, size);
|
|
2081
|
|
2082 return dst;
|
|
2083 }
|
|
2084
|
|
2085
|
|
2086 char *
|
|
2087 ngx_resolver_strerror(ngx_int_t err)
|
|
2088 {
|
|
2089 static char *errors[] = {
|
|
2090 "Format error", /* FORMERR */
|
|
2091 "Server failure", /* SERVFAIL */
|
|
2092 "Host not found", /* NXDOMAIN */
|
|
2093 "Unimplemented", /* NOTIMP */
|
|
2094 "Operation refused" /* REFUSED */
|
|
2095 };
|
|
2096
|
|
2097 if (err > 0 && err < 6) {
|
|
2098 return errors[err - 1];
|
|
2099 }
|
|
2100
|
|
2101 if (err == NGX_RESOLVE_TIMEDOUT) {
|
|
2102 return "Operation timed out";
|
|
2103 }
|
|
2104
|
|
2105 return "Unknown error";
|
|
2106 }
|
|
2107
|
|
2108
|
560
|
2109 static u_char *
|
|
2110 ngx_resolver_log_error(ngx_log_t *log, u_char *buf, size_t len)
|
|
2111 {
|
|
2112 u_char *p;
|
|
2113 ngx_udp_connection_t *uc;
|
|
2114
|
|
2115 p = buf;
|
|
2116
|
|
2117 if (log->action) {
|
|
2118 p = ngx_snprintf(buf, len, " while %s", log->action);
|
|
2119 len -= p - buf;
|
|
2120 }
|
|
2121
|
|
2122 uc = log->data;
|
|
2123
|
|
2124 if (uc) {
|
|
2125 p = ngx_snprintf(p, len, ", resolver: %V", &uc->server);
|
|
2126 }
|
|
2127
|
|
2128 return p;
|
|
2129 }
|
|
2130
|
|
2131
|
350
|
2132 ngx_int_t
|
|
2133 ngx_udp_connect(ngx_udp_connection_t *uc)
|
|
2134 {
|
|
2135 int rc;
|
|
2136 ngx_int_t event;
|
|
2137 ngx_event_t *rev, *wev;
|
|
2138 ngx_socket_t s;
|
|
2139 ngx_connection_t *c;
|
|
2140
|
|
2141 s = ngx_socket(AF_INET, SOCK_DGRAM, 0);
|
|
2142
|
560
|
2143 ngx_log_debug1(NGX_LOG_DEBUG_EVENT, &uc->log, 0, "UDP socket %d", s);
|
350
|
2144
|
|
2145 if (s == -1) {
|
560
|
2146 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2147 ngx_socket_n " failed");
|
|
2148 return NGX_ERROR;
|
|
2149 }
|
|
2150
|
560
|
2151 c = ngx_get_connection(s, &uc->log);
|
350
|
2152
|
|
2153 if (c == NULL) {
|
|
2154 if (ngx_close_socket(s) == -1) {
|
560
|
2155 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2156 ngx_close_socket_n "failed");
|
|
2157 }
|
|
2158
|
|
2159 return NGX_ERROR;
|
|
2160 }
|
|
2161
|
|
2162 if (ngx_nonblocking(s) == -1) {
|
560
|
2163 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2164 ngx_nonblocking_n " failed");
|
|
2165
|
|
2166 ngx_free_connection(c);
|
|
2167
|
|
2168 if (ngx_close_socket(s) == -1) {
|
560
|
2169 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2170 ngx_close_socket_n " failed");
|
|
2171 }
|
|
2172
|
|
2173 return NGX_ERROR;
|
|
2174 }
|
|
2175
|
|
2176 rev = c->read;
|
|
2177 wev = c->write;
|
|
2178
|
560
|
2179 rev->log = &uc->log;
|
|
2180 wev->log = &uc->log;
|
350
|
2181
|
|
2182 uc->connection = c;
|
|
2183
|
|
2184 c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1);
|
|
2185
|
|
2186 #if (NGX_THREADS)
|
|
2187
|
|
2188 /* TODO: lock event when call completion handler */
|
|
2189
|
|
2190 rev->lock = &c->lock;
|
|
2191 wev->lock = &c->lock;
|
|
2192 rev->own_lock = &c->lock;
|
|
2193 wev->own_lock = &c->lock;
|
|
2194
|
|
2195 #endif
|
|
2196
|
560
|
2197 ngx_log_debug3(NGX_LOG_DEBUG_EVENT, &uc->log, 0,
|
350
|
2198 "connect to %V, fd:%d #%d", &uc->server, s, c->number);
|
|
2199
|
|
2200 rc = connect(s, uc->sockaddr, uc->socklen);
|
|
2201
|
|
2202 /* TODO: aio, iocp */
|
|
2203
|
|
2204 if (rc == -1) {
|
560
|
2205 ngx_log_error(NGX_LOG_CRIT, &uc->log, ngx_socket_errno,
|
|
2206 "connect() failed");
|
350
|
2207
|
|
2208 return NGX_ERROR;
|
|
2209 }
|
|
2210
|
|
2211 /* UDP sockets are always ready to write */
|
|
2212 wev->ready = 1;
|
|
2213
|
|
2214 if (ngx_add_event) {
|
|
2215
|
|
2216 event = (ngx_event_flags & NGX_USE_CLEAR_EVENT) ?
|
|
2217 /* kqueue, epoll */ NGX_CLEAR_EVENT:
|
|
2218 /* select, poll, /dev/poll */ NGX_LEVEL_EVENT;
|
|
2219 /* eventport event type has no meaning: oneshot only */
|
|
2220
|
|
2221 if (ngx_add_event(rev, NGX_READ_EVENT, event) != NGX_OK) {
|
|
2222 return NGX_ERROR;
|
|
2223 }
|
|
2224
|
|
2225 } else {
|
|
2226 /* rtsig */
|
|
2227
|
|
2228 if (ngx_add_conn(c) == NGX_ERROR) {
|
|
2229 return NGX_ERROR;
|
|
2230 }
|
|
2231 }
|
|
2232
|
|
2233 return NGX_OK;
|
|
2234 }
|