350
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1
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2 /*
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3 * Copyright (C) Igor Sysoev
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660
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4 * Copyright (C) Nginx, Inc.
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350
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5 */
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6
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7
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8 #include <ngx_config.h>
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9 #include <ngx_core.h>
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10 #include <ngx_event.h>
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11
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12
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13 #define NGX_RESOLVER_UDP_SIZE 4096
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14
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15
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16 typedef struct {
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17 u_char ident_hi;
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18 u_char ident_lo;
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19 u_char flags_hi;
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20 u_char flags_lo;
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21 u_char nqs_hi;
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22 u_char nqs_lo;
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23 u_char nan_hi;
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24 u_char nan_lo;
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25 u_char nns_hi;
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26 u_char nns_lo;
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27 u_char nar_hi;
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28 u_char nar_lo;
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29 } ngx_resolver_query_t;
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30
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31
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32 typedef struct {
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33 u_char type_hi;
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34 u_char type_lo;
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35 u_char class_hi;
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36 u_char class_lo;
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37 } ngx_resolver_qs_t;
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38
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39
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40 typedef struct {
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41 u_char type_hi;
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42 u_char type_lo;
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43 u_char class_hi;
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44 u_char class_lo;
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45 u_char ttl[4];
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46 u_char len_hi;
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47 u_char len_lo;
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48 } ngx_resolver_an_t;
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49
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50
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51 ngx_int_t ngx_udp_connect(ngx_udp_connection_t *uc);
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52
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53
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366
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54 static void ngx_resolver_cleanup(void *data);
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55 static void ngx_resolver_cleanup_tree(ngx_resolver_t *r, ngx_rbtree_t *tree);
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350
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56 static ngx_int_t ngx_resolve_name_locked(ngx_resolver_t *r,
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57 ngx_resolver_ctx_t *ctx);
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58 static void ngx_resolver_expire(ngx_resolver_t *r, ngx_rbtree_t *tree,
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59 ngx_queue_t *queue);
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60 static ngx_int_t ngx_resolver_send_query(ngx_resolver_t *r,
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61 ngx_resolver_node_t *rn);
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62 static ngx_int_t ngx_resolver_create_name_query(ngx_resolver_node_t *rn,
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63 ngx_resolver_ctx_t *ctx);
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64 static ngx_int_t ngx_resolver_create_addr_query(ngx_resolver_node_t *rn,
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65 ngx_resolver_ctx_t *ctx);
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66 static void ngx_resolver_resend_handler(ngx_event_t *ev);
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67 static time_t ngx_resolver_resend(ngx_resolver_t *r, ngx_rbtree_t *tree,
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68 ngx_queue_t *queue);
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69 static void ngx_resolver_read_response(ngx_event_t *rev);
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70 static void ngx_resolver_process_response(ngx_resolver_t *r, u_char *buf,
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71 size_t n);
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72 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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73 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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74 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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75 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan);
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350
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76 static ngx_resolver_node_t *ngx_resolver_lookup_name(ngx_resolver_t *r,
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77 ngx_str_t *name, uint32_t hash);
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78 static ngx_resolver_node_t *ngx_resolver_lookup_addr(ngx_resolver_t *r,
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79 in_addr_t addr);
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80 static void ngx_resolver_rbtree_insert_value(ngx_rbtree_node_t *temp,
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81 ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel);
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82 static ngx_int_t ngx_resolver_copy(ngx_resolver_t *r, ngx_str_t *name,
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83 u_char *buf, u_char *src, u_char *last);
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84 static void ngx_resolver_timeout_handler(ngx_event_t *ev);
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85 static void ngx_resolver_free_node(ngx_resolver_t *r, ngx_resolver_node_t *rn);
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86 static void *ngx_resolver_alloc(ngx_resolver_t *r, size_t size);
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366
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87 static void *ngx_resolver_calloc(ngx_resolver_t *r, size_t size);
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350
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88 static void ngx_resolver_free(ngx_resolver_t *r, void *p);
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89 static void ngx_resolver_free_locked(ngx_resolver_t *r, void *p);
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90 static void *ngx_resolver_dup(ngx_resolver_t *r, void *src, size_t size);
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560
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91 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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92
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93
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94 ngx_resolver_t *
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646
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95 ngx_resolver_create(ngx_conf_t *cf, ngx_str_t *names, ngx_uint_t n)
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350
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96 {
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650
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97 ngx_str_t s;
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646
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98 ngx_url_t u;
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99 ngx_uint_t i;
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350
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100 ngx_resolver_t *r;
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366
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101 ngx_pool_cleanup_t *cln;
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350
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102 ngx_udp_connection_t *uc;
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103
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366
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104 cln = ngx_pool_cleanup_add(cf->pool, 0);
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105 if (cln == NULL) {
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106 return NULL;
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107 }
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108
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109 cln->handler = ngx_resolver_cleanup;
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110
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111 r = ngx_calloc(sizeof(ngx_resolver_t), cf->log);
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350
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112 if (r == NULL) {
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113 return NULL;
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114 }
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115
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646
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116 if (n) {
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117 if (ngx_array_init(&r->udp_connections, cf->pool, n,
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118 sizeof(ngx_udp_connection_t))
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119 != NGX_OK)
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120 {
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121 return NULL;
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122 }
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123 }
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124
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366
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125 cln->data = r;
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126
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127 r->event = ngx_calloc(sizeof(ngx_event_t), cf->log);
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350
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128 if (r->event == NULL) {
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129 return NULL;
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130 }
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131
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354
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132 ngx_rbtree_init(&r->name_rbtree, &r->name_sentinel,
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133 ngx_resolver_rbtree_insert_value);
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134
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135 ngx_rbtree_init(&r->addr_rbtree, &r->addr_sentinel,
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136 ngx_rbtree_insert_value);
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137
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138 ngx_queue_init(&r->name_resend_queue);
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139 ngx_queue_init(&r->addr_resend_queue);
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140
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141 ngx_queue_init(&r->name_expire_queue);
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142 ngx_queue_init(&r->addr_expire_queue);
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350
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143
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144 r->event->handler = ngx_resolver_resend_handler;
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145 r->event->data = r;
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484
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146 r->event->log = &cf->cycle->new_log;
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147 r->ident = -1;
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148
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149 r->resend_timeout = 5;
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150 r->expire = 30;
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650
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151 r->valid = 0;
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350
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152
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484
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153 r->log = &cf->cycle->new_log;
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598
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154 r->log_level = NGX_LOG_ERR;
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350
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155
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646
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156 for (i = 0; i < n; i++) {
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650
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157 if (ngx_strncmp(names[i].data, "valid=", 6) == 0) {
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158 s.len = names[i].len - 6;
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159 s.data = names[i].data + 6;
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160
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161 r->valid = ngx_parse_time(&s, 1);
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162
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662
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163 if (r->valid == (time_t) NGX_ERROR) {
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650
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164 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
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165 "invalid parameter: %V", &names[i]);
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166 return NULL;
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167 }
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168
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169 continue;
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170 }
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171
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646
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172 ngx_memzero(&u, sizeof(ngx_url_t));
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173
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174 u.host = names[i];
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175 u.port = 53;
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176
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177 if (ngx_inet_resolve_host(cf->pool, &u) != NGX_OK) {
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178 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%V: %s", &u.host, u.err);
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179 return NULL;
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180 }
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181
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182 uc = ngx_array_push(&r->udp_connections);
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183 if (uc == NULL) {
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184 return NULL;
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185 }
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186
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646
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187 ngx_memzero(uc, sizeof(ngx_udp_connection_t));
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188
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189 uc->sockaddr = u.addrs->sockaddr;
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190 uc->socklen = u.addrs->socklen;
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191 uc->server = u.addrs->name;
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354
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192 }
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350
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193
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194 return r;
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195 }
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196
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197
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366
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198 static void
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199 ngx_resolver_cleanup(void *data)
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200 {
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201 ngx_resolver_t *r = data;
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202
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646
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203 ngx_uint_t i;
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204 ngx_udp_connection_t *uc;
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205
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366
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206 if (r) {
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207 ngx_log_debug0(NGX_LOG_DEBUG_CORE, ngx_cycle->log, 0,
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208 "cleanup resolver");
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209
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210 ngx_resolver_cleanup_tree(r, &r->name_rbtree);
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211
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212 ngx_resolver_cleanup_tree(r, &r->addr_rbtree);
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213
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214 if (r->event) {
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215 ngx_free(r->event);
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216 }
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217
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646
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218
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219 uc = r->udp_connections.elts;
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220
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221 for (i = 0; i < r->udp_connections.nelts; i++) {
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222 if (uc[i].connection) {
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223 ngx_close_connection(uc[i].connection);
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366
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224 }
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225 }
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226
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227 ngx_free(r);
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228 }
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229 }
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230
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231
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232 static void
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233 ngx_resolver_cleanup_tree(ngx_resolver_t *r, ngx_rbtree_t *tree)
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234 {
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235 ngx_resolver_ctx_t *ctx, *next;
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236 ngx_resolver_node_t *rn;
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237
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238 while (tree->root != tree->sentinel) {
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239
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240 rn = (ngx_resolver_node_t *) ngx_rbtree_min(tree->root, tree->sentinel);
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241
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242 ngx_queue_remove(&rn->queue);
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243
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244 for (ctx = rn->waiting; ctx; ctx = next) {
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376
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245 next = ctx->next;
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366
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246
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247 if (ctx->event) {
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248 ngx_resolver_free(r, ctx->event);
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249 }
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250
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251 ngx_resolver_free(r, ctx);
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252 }
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253
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254 ngx_rbtree_delete(tree, &rn->node);
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255
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256 ngx_resolver_free_node(r, rn);
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257 }
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258 }
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259
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260
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350
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261 ngx_resolver_ctx_t *
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262 ngx_resolve_start(ngx_resolver_t *r, ngx_resolver_ctx_t *temp)
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263 {
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264 in_addr_t addr;
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265 ngx_resolver_ctx_t *ctx;
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266
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267 if (temp) {
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268 addr = ngx_inet_addr(temp->name.data, temp->name.len);
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269
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270 if (addr != INADDR_NONE) {
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271 temp->resolver = r;
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272 temp->state = NGX_OK;
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273 temp->naddrs = 1;
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274 temp->addrs = &temp->addr;
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275 temp->addr = addr;
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276 temp->quick = 1;
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277
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278 return temp;
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279 }
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280 }
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281
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646
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282 if (r->udp_connections.nelts == 0) {
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283 return NGX_NO_RESOLVER;
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284 }
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285
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350
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286 ctx = ngx_resolver_calloc(r, sizeof(ngx_resolver_ctx_t));
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287
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288 if (ctx) {
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289 ctx->resolver = r;
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290 }
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291
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292 return ctx;
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293 }
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294
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295
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296 ngx_int_t
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297 ngx_resolve_name(ngx_resolver_ctx_t *ctx)
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298 {
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299 ngx_int_t rc;
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300 ngx_resolver_t *r;
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301
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302 r = ctx->resolver;
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303
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304 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
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305 "resolve: \"%V\"", &ctx->name);
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306
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307 if (ctx->quick) {
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308 ctx->handler(ctx);
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309 return NGX_OK;
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310 }
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311
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312 /* lock name mutex */
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313
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314 rc = ngx_resolve_name_locked(r, ctx);
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315
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316 if (rc == NGX_OK) {
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317 return NGX_OK;
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318 }
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319
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320 /* unlock name mutex */
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321
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322 if (rc == NGX_AGAIN) {
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323 return NGX_OK;
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324 }
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325
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366
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326 /* NGX_ERROR */
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350
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327
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328 if (ctx->event) {
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366
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329 ngx_resolver_free(r, ctx->event);
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350
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330 }
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331
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366
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332 ngx_resolver_free(r, ctx);
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350
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333
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334 return NGX_ERROR;
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335 }
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336
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337
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338 void
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339 ngx_resolve_name_done(ngx_resolver_ctx_t *ctx)
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340 {
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341 uint32_t hash;
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342 ngx_resolver_t *r;
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343 ngx_resolver_ctx_t *w, **p;
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344 ngx_resolver_node_t *rn;
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345
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346 r = ctx->resolver;
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347
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348 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
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349 "resolve name done: %i", ctx->state);
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350
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351 if (ctx->quick) {
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352 return;
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353 }
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354
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355 if (ctx->event && ctx->event->timer_set) {
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356 ngx_del_timer(ctx->event);
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357 }
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358
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359 /* lock name mutex */
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360
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361 if (ctx->state == NGX_AGAIN || ctx->state == NGX_RESOLVE_TIMEDOUT) {
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362
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363 hash = ngx_crc32_short(ctx->name.data, ctx->name.len);
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364
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365 rn = ngx_resolver_lookup_name(r, &ctx->name, hash);
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366
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367 if (rn) {
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368 p = &rn->waiting;
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369 w = rn->waiting;
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370
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371 while (w) {
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372 if (w == ctx) {
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373 *p = w->next;
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374
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375 goto done;
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376 }
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377
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378 p = &w->next;
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379 w = w->next;
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380 }
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381 }
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382
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383 ngx_log_error(NGX_LOG_ALERT, r->log, 0,
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384 "could not cancel %V resolving", &ctx->name);
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385 }
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386
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387 done:
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388
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389 ngx_resolver_expire(r, &r->name_rbtree, &r->name_expire_queue);
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390
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391 /* unlock name mutex */
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392
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366
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393 /* lock alloc mutex */
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394
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395 if (ctx->event) {
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396 ngx_resolver_free_locked(r, ctx->event);
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397 }
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398
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399 ngx_resolver_free_locked(r, ctx);
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400
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401 /* unlock alloc mutex */
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350
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402 }
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403
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404
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405 /* NGX_RESOLVE_A only */
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406
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407 static ngx_int_t
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408 ngx_resolve_name_locked(ngx_resolver_t *r, ngx_resolver_ctx_t *ctx)
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409 {
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410 uint32_t hash;
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411 in_addr_t addr, *addrs;
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372
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412 ngx_int_t rc;
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350
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413 ngx_uint_t naddrs;
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414 ngx_resolver_ctx_t *next;
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415 ngx_resolver_node_t *rn;
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416
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417 hash = ngx_crc32_short(ctx->name.data, ctx->name.len);
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418
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419 rn = ngx_resolver_lookup_name(r, &ctx->name, hash);
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420
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421 if (rn) {
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422
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423 if (rn->valid >= ngx_time()) {
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424
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425 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolve cached");
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426
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427 ngx_queue_remove(&rn->queue);
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428
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429 rn->expire = ngx_time() + r->expire;
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430
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431 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue);
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432
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433 naddrs = rn->naddrs;
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434
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435 if (naddrs) {
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436
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437 /* NGX_RESOLVE_A answer */
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438
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439 if (naddrs != 1) {
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440 addr = 0;
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441 addrs = ngx_resolver_dup(r, rn->u.addrs,
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442 naddrs * sizeof(in_addr_t));
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443 if (addrs == NULL) {
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444 return NGX_ERROR;
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445 }
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446
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447 } else {
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448 addr = rn->u.addr;
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449 addrs = NULL;
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450 }
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451
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452 ctx->next = rn->waiting;
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453 rn->waiting = NULL;
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454
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455 /* unlock name mutex */
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456
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457 do {
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458 ctx->state = NGX_OK;
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459 ctx->naddrs = naddrs;
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460 ctx->addrs = (naddrs == 1) ? &ctx->addr : addrs;
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461 ctx->addr = addr;
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462 next = ctx->next;
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463
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464 ctx->handler(ctx);
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465
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466 ctx = next;
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467 } while (ctx);
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468
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469 if (addrs) {
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470 ngx_resolver_free(r, addrs);
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471 }
|
|
472
|
|
473 return NGX_OK;
|
|
474 }
|
|
475
|
|
476 /* NGX_RESOLVE_CNAME */
|
|
477
|
372
|
478 if (ctx->recursion++ < NGX_RESOLVER_MAX_RECURSION) {
|
|
479
|
|
480 ctx->name.len = rn->cnlen;
|
|
481 ctx->name.data = rn->u.cname;
|
|
482
|
|
483 return ngx_resolve_name_locked(r, ctx);
|
|
484 }
|
|
485
|
|
486 ctx->next = rn->waiting;
|
|
487 rn->waiting = NULL;
|
|
488
|
|
489 /* unlock name mutex */
|
|
490
|
|
491 do {
|
|
492 ctx->state = NGX_RESOLVE_NXDOMAIN;
|
|
493 next = ctx->next;
|
|
494
|
|
495 ctx->handler(ctx);
|
|
496
|
|
497 ctx = next;
|
|
498 } while (ctx);
|
|
499
|
|
500 return NGX_OK;
|
350
|
501 }
|
|
502
|
|
503 if (rn->waiting) {
|
|
504
|
|
505 ctx->next = rn->waiting;
|
|
506 rn->waiting = ctx;
|
542
|
507 ctx->state = NGX_AGAIN;
|
350
|
508
|
|
509 return NGX_AGAIN;
|
|
510 }
|
|
511
|
|
512 ngx_queue_remove(&rn->queue);
|
|
513
|
|
514 /* lock alloc mutex */
|
|
515
|
|
516 ngx_resolver_free_locked(r, rn->query);
|
372
|
517 rn->query = NULL;
|
350
|
518
|
|
519 if (rn->cnlen) {
|
|
520 ngx_resolver_free_locked(r, rn->u.cname);
|
|
521 }
|
|
522
|
|
523 if (rn->naddrs > 1) {
|
|
524 ngx_resolver_free_locked(r, rn->u.addrs);
|
|
525 }
|
|
526
|
|
527 /* unlock alloc mutex */
|
|
528
|
|
529 } else {
|
|
530
|
|
531 rn = ngx_resolver_alloc(r, sizeof(ngx_resolver_node_t));
|
|
532 if (rn == NULL) {
|
|
533 return NGX_ERROR;
|
|
534 }
|
|
535
|
|
536 rn->name = ngx_resolver_dup(r, ctx->name.data, ctx->name.len);
|
|
537 if (rn->name == NULL) {
|
|
538 ngx_resolver_free(r, rn);
|
|
539 return NGX_ERROR;
|
|
540 }
|
|
541
|
|
542 rn->node.key = hash;
|
|
543 rn->nlen = (u_short) ctx->name.len;
|
372
|
544 rn->query = NULL;
|
350
|
545
|
|
546 ngx_rbtree_insert(&r->name_rbtree, &rn->node);
|
|
547 }
|
|
548
|
372
|
549 rc = ngx_resolver_create_name_query(rn, ctx);
|
|
550
|
|
551 if (rc == NGX_ERROR) {
|
350
|
552 goto failed;
|
|
553 }
|
|
554
|
372
|
555 if (rc == NGX_DECLINED) {
|
|
556 ngx_rbtree_delete(&r->name_rbtree, &rn->node);
|
|
557
|
|
558 ngx_resolver_free(r, rn->query);
|
|
559 ngx_resolver_free(r, rn->name);
|
|
560 ngx_resolver_free(r, rn);
|
|
561
|
|
562 ctx->state = NGX_RESOLVE_NXDOMAIN;
|
|
563 ctx->handler(ctx);
|
|
564
|
|
565 return NGX_OK;
|
|
566 }
|
|
567
|
350
|
568 if (ngx_resolver_send_query(r, rn) != NGX_OK) {
|
|
569 goto failed;
|
|
570 }
|
|
571
|
|
572 if (ctx->event == NULL) {
|
|
573 ctx->event = ngx_resolver_calloc(r, sizeof(ngx_event_t));
|
|
574 if (ctx->event == NULL) {
|
|
575 goto failed;
|
|
576 }
|
|
577
|
|
578 ctx->event->handler = ngx_resolver_timeout_handler;
|
|
579 ctx->event->data = ctx;
|
|
580 ctx->event->log = r->log;
|
|
581 ctx->ident = -1;
|
|
582
|
|
583 ngx_add_timer(ctx->event, ctx->timeout);
|
|
584 }
|
|
585
|
|
586 if (ngx_queue_empty(&r->name_resend_queue)) {
|
|
587 ngx_add_timer(r->event, (ngx_msec_t) (r->resend_timeout * 1000));
|
|
588 }
|
|
589
|
|
590 rn->expire = ngx_time() + r->resend_timeout;
|
|
591
|
|
592 ngx_queue_insert_head(&r->name_resend_queue, &rn->queue);
|
|
593
|
|
594 rn->cnlen = 0;
|
|
595 rn->naddrs = 0;
|
|
596 rn->valid = 0;
|
|
597 rn->waiting = ctx;
|
|
598
|
|
599 ctx->state = NGX_AGAIN;
|
|
600
|
|
601 return NGX_AGAIN;
|
|
602
|
|
603 failed:
|
|
604
|
|
605 ngx_rbtree_delete(&r->name_rbtree, &rn->node);
|
|
606
|
372
|
607 if (rn->query) {
|
|
608 ngx_resolver_free(r, rn->query);
|
|
609 }
|
|
610
|
350
|
611 ngx_resolver_free(r, rn->name);
|
|
612
|
|
613 ngx_resolver_free(r, rn);
|
|
614
|
|
615 return NGX_ERROR;
|
|
616 }
|
|
617
|
|
618
|
|
619 ngx_int_t
|
|
620 ngx_resolve_addr(ngx_resolver_ctx_t *ctx)
|
|
621 {
|
442
|
622 u_char *name;
|
350
|
623 ngx_resolver_t *r;
|
|
624 ngx_resolver_node_t *rn;
|
|
625
|
|
626 r = ctx->resolver;
|
|
627
|
|
628 ctx->addr = ntohl(ctx->addr);
|
|
629
|
|
630 /* lock addr mutex */
|
|
631
|
|
632 rn = ngx_resolver_lookup_addr(r, ctx->addr);
|
|
633
|
|
634 if (rn) {
|
|
635
|
|
636 if (rn->valid >= ngx_time()) {
|
|
637
|
|
638 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolve cached");
|
|
639
|
|
640 ngx_queue_remove(&rn->queue);
|
|
641
|
|
642 rn->expire = ngx_time() + r->expire;
|
|
643
|
|
644 ngx_queue_insert_head(&r->addr_expire_queue, &rn->queue);
|
|
645
|
442
|
646 name = ngx_resolver_dup(r, rn->name, rn->nlen);
|
|
647 if (name == NULL) {
|
350
|
648 goto failed;
|
|
649 }
|
|
650
|
442
|
651 ctx->name.len = rn->nlen;
|
|
652 ctx->name.data = name;
|
|
653
|
350
|
654 /* unlock addr mutex */
|
|
655
|
|
656 ctx->state = NGX_OK;
|
|
657
|
|
658 ctx->handler(ctx);
|
|
659
|
442
|
660 ngx_resolver_free(r, name);
|
350
|
661
|
|
662 return NGX_OK;
|
|
663 }
|
|
664
|
|
665 if (rn->waiting) {
|
|
666
|
|
667 ctx->next = rn->waiting;
|
|
668 rn->waiting = ctx;
|
542
|
669 ctx->state = NGX_AGAIN;
|
350
|
670
|
442
|
671 /* unlock addr mutex */
|
|
672
|
|
673 return NGX_OK;
|
350
|
674 }
|
|
675
|
|
676 ngx_queue_remove(&rn->queue);
|
|
677
|
|
678 ngx_resolver_free(r, rn->query);
|
372
|
679 rn->query = NULL;
|
350
|
680
|
|
681 } else {
|
|
682 rn = ngx_resolver_alloc(r, sizeof(ngx_resolver_node_t));
|
|
683 if (rn == NULL) {
|
|
684 goto failed;
|
|
685 }
|
|
686
|
|
687 rn->node.key = ctx->addr;
|
372
|
688 rn->query = NULL;
|
350
|
689
|
|
690 ngx_rbtree_insert(&r->addr_rbtree, &rn->node);
|
|
691 }
|
|
692
|
|
693 if (ngx_resolver_create_addr_query(rn, ctx) != NGX_OK) {
|
|
694 goto failed;
|
|
695 }
|
|
696
|
|
697 if (ngx_resolver_send_query(r, rn) != NGX_OK) {
|
|
698 goto failed;
|
|
699 }
|
|
700
|
|
701 ctx->event = ngx_resolver_calloc(r, sizeof(ngx_event_t));
|
|
702 if (ctx->event == NULL) {
|
|
703 goto failed;
|
|
704 }
|
|
705
|
|
706 ctx->event->handler = ngx_resolver_timeout_handler;
|
|
707 ctx->event->data = ctx;
|
|
708 ctx->event->log = r->log;
|
|
709 ctx->ident = -1;
|
|
710
|
|
711 ngx_add_timer(ctx->event, ctx->timeout);
|
|
712
|
|
713 if (ngx_queue_empty(&r->addr_resend_queue)) {
|
|
714 ngx_add_timer(r->event, (ngx_msec_t) (r->resend_timeout * 1000));
|
|
715 }
|
|
716
|
|
717 rn->expire = ngx_time() + r->resend_timeout;
|
|
718
|
|
719 ngx_queue_insert_head(&r->addr_resend_queue, &rn->queue);
|
|
720
|
|
721 rn->cnlen = 0;
|
|
722 rn->naddrs = 0;
|
|
723 rn->name = NULL;
|
|
724 rn->nlen = 0;
|
|
725 rn->valid = 0;
|
|
726 rn->waiting = ctx;
|
|
727
|
|
728 /* unlock addr mutex */
|
|
729
|
|
730 ctx->state = NGX_AGAIN;
|
|
731
|
|
732 return NGX_OK;
|
|
733
|
|
734 failed:
|
|
735
|
|
736 if (rn) {
|
|
737 ngx_rbtree_delete(&r->addr_rbtree, &rn->node);
|
|
738
|
372
|
739 if (rn->query) {
|
|
740 ngx_resolver_free(r, rn->query);
|
|
741 }
|
|
742
|
350
|
743 ngx_resolver_free(r, rn);
|
|
744 }
|
|
745
|
|
746 /* unlock addr mutex */
|
|
747
|
|
748 if (ctx->event) {
|
366
|
749 ngx_resolver_free(r, ctx->event);
|
350
|
750 }
|
|
751
|
366
|
752 ngx_resolver_free(r, ctx);
|
350
|
753
|
|
754 return NGX_ERROR;
|
|
755 }
|
|
756
|
|
757
|
|
758 void
|
|
759 ngx_resolve_addr_done(ngx_resolver_ctx_t *ctx)
|
|
760 {
|
|
761 in_addr_t addr;
|
|
762 ngx_resolver_t *r;
|
|
763 ngx_resolver_ctx_t *w, **p;
|
|
764 ngx_resolver_node_t *rn;
|
|
765
|
|
766 r = ctx->resolver;
|
|
767
|
|
768 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
769 "resolve addr done: %i", ctx->state);
|
|
770
|
|
771 if (ctx->event && ctx->event->timer_set) {
|
|
772 ngx_del_timer(ctx->event);
|
|
773 }
|
|
774
|
|
775 /* lock addr mutex */
|
|
776
|
|
777 if (ctx->state == NGX_AGAIN || ctx->state == NGX_RESOLVE_TIMEDOUT) {
|
|
778
|
|
779 rn = ngx_resolver_lookup_addr(r, ctx->addr);
|
|
780
|
|
781 if (rn) {
|
|
782 p = &rn->waiting;
|
|
783 w = rn->waiting;
|
|
784
|
|
785 while (w) {
|
|
786 if (w == ctx) {
|
|
787 *p = w->next;
|
|
788
|
|
789 goto done;
|
|
790 }
|
|
791
|
|
792 p = &w->next;
|
|
793 w = w->next;
|
|
794 }
|
|
795 }
|
|
796
|
|
797 addr = ntohl(ctx->addr);
|
|
798
|
|
799 ngx_log_error(NGX_LOG_ALERT, r->log, 0,
|
|
800 "could not cancel %ud.%ud.%ud.%ud resolving",
|
|
801 (addr >> 24) & 0xff, (addr >> 16) & 0xff,
|
|
802 (addr >> 8) & 0xff, addr & 0xff);
|
|
803 }
|
|
804
|
|
805 done:
|
|
806
|
|
807 ngx_resolver_expire(r, &r->addr_rbtree, &r->addr_expire_queue);
|
|
808
|
|
809 /* unlock addr mutex */
|
|
810
|
366
|
811 /* lock alloc mutex */
|
|
812
|
|
813 if (ctx->event) {
|
|
814 ngx_resolver_free_locked(r, ctx->event);
|
|
815 }
|
|
816
|
|
817 ngx_resolver_free_locked(r, ctx);
|
|
818
|
|
819 /* unlock alloc mutex */
|
350
|
820 }
|
|
821
|
|
822
|
|
823 static void
|
|
824 ngx_resolver_expire(ngx_resolver_t *r, ngx_rbtree_t *tree, ngx_queue_t *queue)
|
|
825 {
|
|
826 time_t now;
|
|
827 ngx_uint_t i;
|
|
828 ngx_queue_t *q;
|
|
829 ngx_resolver_node_t *rn;
|
|
830
|
|
831 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver expire");
|
|
832
|
|
833 now = ngx_time();
|
|
834
|
|
835 for (i = 0; i < 2; i++) {
|
|
836 if (ngx_queue_empty(queue)) {
|
|
837 return;
|
|
838 }
|
|
839
|
|
840 q = ngx_queue_last(queue);
|
|
841
|
|
842 rn = ngx_queue_data(q, ngx_resolver_node_t, queue);
|
|
843
|
|
844 if (now <= rn->expire) {
|
|
845 return;
|
|
846 }
|
|
847
|
358
|
848 ngx_log_debug2(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
849 "resolver expire \"%*s\"", (size_t) rn->nlen, rn->name);
|
350
|
850
|
|
851 ngx_queue_remove(q);
|
|
852
|
|
853 ngx_rbtree_delete(tree, &rn->node);
|
|
854
|
|
855 ngx_resolver_free_node(r, rn);
|
|
856 }
|
|
857 }
|
|
858
|
|
859
|
|
860 static ngx_int_t
|
|
861 ngx_resolver_send_query(ngx_resolver_t *r, ngx_resolver_node_t *rn)
|
|
862 {
|
|
863 ssize_t n;
|
|
864 ngx_udp_connection_t *uc;
|
|
865
|
646
|
866 uc = r->udp_connections.elts;
|
|
867
|
|
868 uc = &uc[r->last_connection++];
|
|
869 if (r->last_connection == r->udp_connections.nelts) {
|
|
870 r->last_connection = 0;
|
|
871 }
|
350
|
872
|
|
873 if (uc->connection == NULL) {
|
664
|
874
|
|
875 uc->log = *r->log;
|
|
876 uc->log.handler = ngx_resolver_log_error;
|
|
877 uc->log.data = uc;
|
|
878 uc->log.action = "resolving";
|
|
879
|
350
|
880 if (ngx_udp_connect(uc) != NGX_OK) {
|
|
881 return NGX_ERROR;
|
|
882 }
|
|
883
|
|
884 uc->connection->data = r;
|
|
885 uc->connection->read->handler = ngx_resolver_read_response;
|
366
|
886 uc->connection->read->resolver = 1;
|
350
|
887 }
|
|
888
|
|
889 n = ngx_send(uc->connection, rn->query, rn->qlen);
|
|
890
|
|
891 if (n == -1) {
|
|
892 return NGX_ERROR;
|
|
893 }
|
|
894
|
|
895 if ((size_t) n != (size_t) rn->qlen) {
|
560
|
896 ngx_log_error(NGX_LOG_CRIT, &uc->log, 0, "send() incomplete");
|
350
|
897 return NGX_ERROR;
|
|
898 }
|
|
899
|
|
900 return NGX_OK;
|
|
901 }
|
|
902
|
|
903
|
|
904 static void
|
|
905 ngx_resolver_resend_handler(ngx_event_t *ev)
|
|
906 {
|
|
907 time_t timer, atimer, ntimer;
|
|
908 ngx_resolver_t *r;
|
|
909
|
|
910 r = ev->data;
|
|
911
|
|
912 ngx_log_debug0(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
913 "resolver resend handler");
|
|
914
|
|
915 /* lock name mutex */
|
|
916
|
|
917 ntimer = ngx_resolver_resend(r, &r->name_rbtree, &r->name_resend_queue);
|
|
918
|
|
919 /* unlock name mutex */
|
|
920
|
|
921 /* lock addr mutex */
|
|
922
|
|
923 atimer = ngx_resolver_resend(r, &r->addr_rbtree, &r->addr_resend_queue);
|
354
|
924
|
350
|
925 /* unlock addr mutex */
|
|
926
|
|
927 if (ntimer == 0) {
|
|
928 timer = atimer;
|
|
929
|
|
930 } else if (atimer == 0) {
|
|
931 timer = ntimer;
|
|
932
|
|
933 } else {
|
|
934 timer = (atimer < ntimer) ? atimer : ntimer;
|
|
935 }
|
|
936
|
|
937 if (timer) {
|
|
938 ngx_add_timer(r->event, (ngx_msec_t) (timer * 1000));
|
|
939 }
|
|
940 }
|
|
941
|
|
942
|
|
943 static time_t
|
|
944 ngx_resolver_resend(ngx_resolver_t *r, ngx_rbtree_t *tree, ngx_queue_t *queue)
|
|
945 {
|
|
946 time_t now;
|
|
947 ngx_queue_t *q;
|
|
948 ngx_resolver_node_t *rn;
|
|
949
|
|
950 now = ngx_time();
|
|
951
|
|
952 for ( ;; ) {
|
|
953 if (ngx_queue_empty(queue)) {
|
|
954 return 0;
|
|
955 }
|
|
956
|
|
957 q = ngx_queue_last(queue);
|
|
958
|
|
959 rn = ngx_queue_data(q, ngx_resolver_node_t, queue);
|
|
960
|
|
961 if (now < rn->expire) {
|
|
962 return rn->expire - now;
|
|
963 }
|
|
964
|
358
|
965 ngx_log_debug3(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
966 "resolver resend \"%*s\" %p",
|
|
967 (size_t) rn->nlen, rn->name, rn->waiting);
|
350
|
968
|
|
969 ngx_queue_remove(q);
|
|
970
|
|
971 if (rn->waiting) {
|
|
972
|
|
973 if (ngx_resolver_send_query(r, rn) == NGX_OK) {
|
|
974
|
|
975 rn->expire = now + r->resend_timeout;
|
|
976
|
|
977 ngx_queue_insert_head(queue, &rn->queue);
|
|
978 }
|
364
|
979
|
|
980 continue;
|
350
|
981 }
|
|
982
|
|
983 ngx_rbtree_delete(tree, &rn->node);
|
|
984
|
|
985 ngx_resolver_free_node(r, rn);
|
|
986 }
|
|
987 }
|
|
988
|
|
989
|
|
990 static void
|
|
991 ngx_resolver_read_response(ngx_event_t *rev)
|
|
992 {
|
|
993 ssize_t n;
|
|
994 ngx_connection_t *c;
|
|
995 u_char buf[NGX_RESOLVER_UDP_SIZE];
|
|
996
|
|
997 c = rev->data;
|
|
998
|
|
999 do {
|
354
|
1000 n = ngx_udp_recv(c, buf, NGX_RESOLVER_UDP_SIZE);
|
|
1001
|
|
1002 if (n < 0) {
|
350
|
1003 return;
|
|
1004 }
|
|
1005
|
|
1006 ngx_resolver_process_response(c->data, buf, n);
|
|
1007
|
|
1008 } while (rev->ready);
|
|
1009 }
|
|
1010
|
|
1011
|
|
1012 static void
|
|
1013 ngx_resolver_process_response(ngx_resolver_t *r, u_char *buf, size_t n)
|
|
1014 {
|
|
1015 char *err;
|
|
1016 size_t len;
|
416
|
1017 ngx_uint_t i, times, ident, qident, flags, code, nqs, nan,
|
|
1018 qtype, qclass;
|
|
1019 ngx_queue_t *q;
|
350
|
1020 ngx_resolver_qs_t *qs;
|
416
|
1021 ngx_resolver_node_t *rn;
|
350
|
1022 ngx_resolver_query_t *query;
|
|
1023
|
416
|
1024 if ((size_t) n < sizeof(ngx_resolver_query_t)) {
|
350
|
1025 goto short_response;
|
|
1026 }
|
|
1027
|
|
1028 query = (ngx_resolver_query_t *) buf;
|
|
1029
|
|
1030 ident = (query->ident_hi << 8) + query->ident_lo;
|
|
1031 flags = (query->flags_hi << 8) + query->flags_lo;
|
|
1032 nqs = (query->nqs_hi << 8) + query->nqs_lo;
|
|
1033 nan = (query->nan_hi << 8) + query->nan_lo;
|
|
1034
|
|
1035 ngx_log_debug6(NGX_LOG_DEBUG_CORE, r->log, 0,
|
372
|
1036 "resolver DNS response %ui fl:%04Xui %ui/%ui/%ui/%ui",
|
350
|
1037 ident, flags, nqs, nan,
|
|
1038 (query->nns_hi << 8) + query->nns_lo,
|
|
1039 (query->nar_hi << 8) + query->nar_lo);
|
|
1040
|
|
1041 if (!(flags & 0x8000)) {
|
|
1042 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1043 "invalid DNS response %ui fl:%04Xui", ident, flags);
|
350
|
1044 return;
|
|
1045 }
|
|
1046
|
|
1047 code = flags & 0x7f;
|
|
1048
|
416
|
1049 if (code == NGX_RESOLVE_FORMERR) {
|
|
1050
|
|
1051 times = 0;
|
|
1052
|
|
1053 for (q = ngx_queue_head(&r->name_resend_queue);
|
|
1054 q != ngx_queue_sentinel(&r->name_resend_queue) || times++ < 100;
|
|
1055 q = ngx_queue_next(q))
|
|
1056 {
|
|
1057 rn = ngx_queue_data(q, ngx_resolver_node_t, queue);
|
|
1058 qident = (rn->query[0] << 8) + rn->query[1];
|
|
1059
|
|
1060 if (qident == ident) {
|
|
1061 ngx_log_error(r->log_level, r->log, 0,
|
|
1062 "DNS error (%ui: %s), query id:%ui, name:\"%*s\"",
|
|
1063 code, ngx_resolver_strerror(code), ident,
|
|
1064 rn->nlen, rn->name);
|
|
1065 return;
|
|
1066 }
|
|
1067 }
|
|
1068
|
|
1069 goto dns_error;
|
|
1070 }
|
|
1071
|
|
1072 if (code > NGX_RESOLVE_REFUSED) {
|
|
1073 goto dns_error;
|
350
|
1074 }
|
|
1075
|
|
1076 if (nqs != 1) {
|
|
1077 err = "invalid number of questions in DNS response";
|
|
1078 goto done;
|
|
1079 }
|
|
1080
|
|
1081 i = sizeof(ngx_resolver_query_t);
|
|
1082
|
|
1083 while (i < (ngx_uint_t) n) {
|
|
1084 if (buf[i] == '\0') {
|
|
1085 goto found;
|
|
1086 }
|
|
1087
|
|
1088 len = buf[i];
|
|
1089 i += 1 + len;
|
|
1090 }
|
|
1091
|
|
1092 goto short_response;
|
|
1093
|
|
1094 found:
|
|
1095
|
|
1096 if (i++ == 0) {
|
|
1097 err = "zero-length domain name in DNS response";
|
|
1098 goto done;
|
|
1099 }
|
|
1100
|
|
1101 if (i + sizeof(ngx_resolver_qs_t) + nan * (2 + sizeof(ngx_resolver_an_t))
|
|
1102 > (ngx_uint_t) n)
|
|
1103 {
|
|
1104 goto short_response;
|
|
1105 }
|
|
1106
|
|
1107 qs = (ngx_resolver_qs_t *) &buf[i];
|
|
1108
|
|
1109 qtype = (qs->type_hi << 8) + qs->type_lo;
|
|
1110 qclass = (qs->class_hi << 8) + qs->class_lo;
|
|
1111
|
|
1112 ngx_log_debug2(NGX_LOG_DEBUG_CORE, r->log, 0,
|
372
|
1113 "resolver DNS response qt:%ui cl:%ui", qtype, qclass);
|
350
|
1114
|
|
1115 if (qclass != 1) {
|
|
1116 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1117 "unknown query class %ui in DNS response", qclass);
|
350
|
1118 return;
|
|
1119 }
|
|
1120
|
|
1121 switch (qtype) {
|
|
1122
|
|
1123 case NGX_RESOLVE_A:
|
|
1124
|
|
1125 ngx_resolver_process_a(r, buf, n, ident, code, nan,
|
356
|
1126 i + sizeof(ngx_resolver_qs_t));
|
350
|
1127
|
|
1128 break;
|
|
1129
|
|
1130 case NGX_RESOLVE_PTR:
|
|
1131
|
356
|
1132 ngx_resolver_process_ptr(r, buf, n, ident, code, nan);
|
350
|
1133
|
|
1134 break;
|
|
1135
|
|
1136 default:
|
|
1137 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1138 "unknown query type %ui in DNS response", qtype);
|
350
|
1139 return;
|
|
1140 }
|
|
1141
|
|
1142 return;
|
|
1143
|
|
1144 short_response:
|
|
1145
|
|
1146 err = "short dns response";
|
|
1147
|
|
1148 done:
|
|
1149
|
|
1150 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1151
|
|
1152 return;
|
416
|
1153
|
|
1154 dns_error:
|
|
1155
|
|
1156 ngx_log_error(r->log_level, r->log, 0,
|
|
1157 "DNS error (%ui: %s), query id:%ui",
|
|
1158 code, ngx_resolver_strerror(code), ident);
|
|
1159 return;
|
350
|
1160 }
|
|
1161
|
|
1162
|
|
1163 static void
|
|
1164 ngx_resolver_process_a(ngx_resolver_t *r, u_char *buf, size_t last,
|
|
1165 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan, ngx_uint_t ans)
|
|
1166 {
|
|
1167 char *err;
|
|
1168 u_char *cname;
|
|
1169 size_t len;
|
650
|
1170 int32_t ttl;
|
350
|
1171 uint32_t hash;
|
|
1172 in_addr_t addr, *addrs;
|
|
1173 ngx_str_t name;
|
|
1174 ngx_uint_t qtype, qident, naddrs, a, i, n, start;
|
|
1175 ngx_resolver_an_t *an;
|
|
1176 ngx_resolver_ctx_t *ctx, *next;
|
|
1177 ngx_resolver_node_t *rn;
|
|
1178
|
|
1179 if (ngx_resolver_copy(r, &name, buf, &buf[12], &buf[last]) != NGX_OK) {
|
|
1180 return;
|
|
1181 }
|
|
1182
|
|
1183 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver qs:%V", &name);
|
|
1184
|
|
1185 hash = ngx_crc32_short(name.data, name.len);
|
|
1186
|
|
1187 /* lock name mutex */
|
|
1188
|
|
1189 rn = ngx_resolver_lookup_name(r, &name, hash);
|
|
1190
|
|
1191 if (rn == NULL || rn->query == NULL) {
|
|
1192 ngx_log_error(r->log_level, r->log, 0,
|
|
1193 "unexpected response for %V", &name);
|
|
1194 goto failed;
|
|
1195 }
|
|
1196
|
|
1197 qident = (rn->query[0] << 8) + rn->query[1];
|
|
1198
|
|
1199 if (ident != qident) {
|
|
1200 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1201 "wrong ident %ui response for %V, expect %ui",
|
350
|
1202 ident, &name, qident);
|
|
1203 goto failed;
|
|
1204 }
|
|
1205
|
528
|
1206 ngx_resolver_free(r, name.data);
|
|
1207
|
356
|
1208 if (code == 0 && nan == 0) {
|
|
1209 code = 3; /* NXDOMAIN */
|
|
1210 }
|
|
1211
|
350
|
1212 if (code) {
|
|
1213 next = rn->waiting;
|
|
1214 rn->waiting = NULL;
|
|
1215
|
|
1216 ngx_queue_remove(&rn->queue);
|
|
1217
|
|
1218 ngx_rbtree_delete(&r->name_rbtree, &rn->node);
|
|
1219
|
|
1220 ngx_resolver_free_node(r, rn);
|
|
1221
|
|
1222 /* unlock name mutex */
|
|
1223
|
|
1224 while (next) {
|
|
1225 ctx = next;
|
|
1226 ctx->state = code;
|
|
1227 next = ctx->next;
|
|
1228
|
|
1229 ctx->handler(ctx);
|
|
1230 }
|
|
1231
|
|
1232 return;
|
|
1233 }
|
|
1234
|
|
1235 i = ans;
|
|
1236 naddrs = 0;
|
|
1237 addr = 0;
|
|
1238 addrs = NULL;
|
|
1239 cname = NULL;
|
|
1240 qtype = 0;
|
650
|
1241 ttl = 0;
|
350
|
1242
|
|
1243 for (a = 0; a < nan; a++) {
|
|
1244
|
|
1245 start = i;
|
|
1246
|
|
1247 while (i < last) {
|
|
1248
|
|
1249 if (buf[i] & 0xc0) {
|
|
1250 i += 2;
|
|
1251 goto found;
|
|
1252 }
|
|
1253
|
|
1254 if (buf[i] == 0) {
|
|
1255 i++;
|
|
1256 goto test_length;
|
|
1257 }
|
|
1258
|
|
1259 i += 1 + buf[i];
|
|
1260 }
|
|
1261
|
|
1262 goto short_response;
|
|
1263
|
|
1264 test_length:
|
|
1265
|
|
1266 if (i - start < 2) {
|
|
1267 err = "invalid name in dns response";
|
|
1268 goto invalid;
|
|
1269 }
|
|
1270
|
|
1271 found:
|
|
1272
|
|
1273 if (i + sizeof(ngx_resolver_an_t) >= last) {
|
|
1274 goto short_response;
|
|
1275 }
|
|
1276
|
|
1277 an = (ngx_resolver_an_t *) &buf[i];
|
|
1278
|
|
1279 qtype = (an->type_hi << 8) + an->type_lo;
|
|
1280 len = (an->len_hi << 8) + an->len_lo;
|
650
|
1281 ttl = (an->ttl[0] << 24) + (an->ttl[1] << 16)
|
|
1282 + (an->ttl[2] << 8) + (an->ttl[3]);
|
|
1283
|
|
1284 if (ttl < 0) {
|
|
1285 ttl = 0;
|
|
1286 }
|
350
|
1287
|
|
1288 if (qtype == NGX_RESOLVE_A) {
|
|
1289
|
|
1290 i += sizeof(ngx_resolver_an_t);
|
|
1291
|
|
1292 if (i + len > last) {
|
|
1293 goto short_response;
|
|
1294 }
|
|
1295
|
|
1296 addr = htonl((buf[i] << 24) + (buf[i + 1] << 16)
|
|
1297 + (buf[i + 2] << 8) + (buf[i + 3]));
|
|
1298
|
|
1299 naddrs++;
|
|
1300
|
|
1301 i += len;
|
|
1302
|
|
1303 } else if (qtype == NGX_RESOLVE_CNAME) {
|
|
1304 cname = &buf[i] + sizeof(ngx_resolver_an_t);
|
|
1305 i += sizeof(ngx_resolver_an_t) + len;
|
372
|
1306
|
|
1307 } else if (qtype == NGX_RESOLVE_DNAME) {
|
|
1308 i += sizeof(ngx_resolver_an_t) + len;
|
|
1309
|
|
1310 } else {
|
|
1311 ngx_log_error(r->log_level, r->log, 0,
|
|
1312 "unexpected qtype %ui", qtype);
|
350
|
1313 }
|
|
1314 }
|
|
1315
|
650
|
1316 ngx_log_debug3(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
1317 "resolver naddrs:%ui cname:%p ttl:%d",
|
|
1318 naddrs, cname, ttl);
|
350
|
1319
|
|
1320 if (naddrs) {
|
|
1321
|
|
1322 if (naddrs == 1) {
|
|
1323 rn->u.addr = addr;
|
|
1324
|
|
1325 } else {
|
|
1326
|
|
1327 addrs = ngx_resolver_alloc(r, naddrs * sizeof(in_addr_t));
|
|
1328 if (addrs == NULL) {
|
|
1329 return;
|
|
1330 }
|
|
1331
|
|
1332 n = 0;
|
|
1333 i = ans;
|
|
1334
|
|
1335 for (a = 0; a < nan; a++) {
|
|
1336
|
|
1337 for ( ;; ) {
|
|
1338
|
|
1339 if (buf[i] & 0xc0) {
|
|
1340 i += 2;
|
|
1341 goto ok;
|
|
1342 }
|
|
1343
|
|
1344 if (buf[i] == 0) {
|
|
1345 i++;
|
|
1346 goto ok;
|
|
1347 }
|
|
1348
|
|
1349 i += 1 + buf[i];
|
|
1350 }
|
|
1351
|
|
1352 ok:
|
|
1353
|
|
1354 an = (ngx_resolver_an_t *) &buf[i];
|
|
1355
|
|
1356 qtype = (an->type_hi << 8) + an->type_lo;
|
|
1357 len = (an->len_hi << 8) + an->len_lo;
|
|
1358
|
|
1359 i += sizeof(ngx_resolver_an_t);
|
|
1360
|
|
1361 if (qtype == NGX_RESOLVE_A) {
|
|
1362
|
|
1363 addrs[n++] = htonl((buf[i] << 24) + (buf[i + 1] << 16)
|
|
1364 + (buf[i + 2] << 8) + (buf[i + 3]));
|
|
1365
|
|
1366 if (n == naddrs) {
|
|
1367 break;
|
|
1368 }
|
|
1369 }
|
|
1370
|
|
1371 i += len;
|
|
1372 }
|
|
1373
|
|
1374 rn->u.addrs = addrs;
|
|
1375
|
|
1376 addrs = ngx_resolver_dup(r, rn->u.addrs,
|
|
1377 naddrs * sizeof(in_addr_t));
|
|
1378 if (addrs == NULL) {
|
|
1379 return;
|
|
1380 }
|
|
1381 }
|
|
1382
|
|
1383 rn->naddrs = (u_short) naddrs;
|
|
1384
|
|
1385 ngx_queue_remove(&rn->queue);
|
|
1386
|
650
|
1387 rn->valid = ngx_time() + (r->valid ? r->valid : ttl);
|
350
|
1388 rn->expire = ngx_time() + r->expire;
|
|
1389
|
|
1390 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue);
|
|
1391
|
|
1392 next = rn->waiting;
|
|
1393 rn->waiting = NULL;
|
|
1394
|
|
1395 /* unlock name mutex */
|
|
1396
|
|
1397 while (next) {
|
|
1398 ctx = next;
|
|
1399 ctx->state = NGX_OK;
|
|
1400 ctx->naddrs = naddrs;
|
|
1401 ctx->addrs = (naddrs == 1) ? &ctx->addr : addrs;
|
|
1402 ctx->addr = addr;
|
|
1403 next = ctx->next;
|
|
1404
|
|
1405 ctx->handler(ctx);
|
|
1406 }
|
|
1407
|
442
|
1408 if (naddrs > 1) {
|
350
|
1409 ngx_resolver_free(r, addrs);
|
|
1410 }
|
|
1411
|
|
1412 return;
|
|
1413
|
|
1414 } else if (cname) {
|
|
1415
|
|
1416 /* CNAME only */
|
|
1417
|
|
1418 if (ngx_resolver_copy(r, &name, buf, cname, &buf[last]) != NGX_OK) {
|
|
1419 return;
|
|
1420 }
|
|
1421
|
|
1422 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0,
|
|
1423 "resolver cname:\"%V\"", &name);
|
|
1424
|
356
|
1425 ngx_queue_remove(&rn->queue);
|
|
1426
|
350
|
1427 rn->cnlen = (u_short) name.len;
|
|
1428 rn->u.cname = name.data;
|
650
|
1429
|
|
1430 rn->valid = ngx_time() + (r->valid ? r->valid : ttl);
|
350
|
1431 rn->expire = ngx_time() + r->expire;
|
|
1432
|
|
1433 ngx_queue_insert_head(&r->name_expire_queue, &rn->queue);
|
|
1434
|
|
1435 ctx = rn->waiting;
|
|
1436 rn->waiting = NULL;
|
|
1437
|
|
1438 if (ctx) {
|
|
1439 ctx->name = name;
|
|
1440
|
|
1441 (void) ngx_resolve_name_locked(r, ctx);
|
|
1442 }
|
|
1443
|
|
1444 return;
|
|
1445 }
|
|
1446
|
|
1447 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1448 "no A or CNAME types in DNS responses, unknown query type: %ui",
|
|
1449 qtype);
|
350
|
1450 return;
|
|
1451
|
|
1452 short_response:
|
|
1453
|
|
1454 err = "short dns response";
|
|
1455
|
|
1456 invalid:
|
|
1457
|
|
1458 /* unlock name mutex */
|
|
1459
|
|
1460 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1461
|
|
1462 return;
|
|
1463
|
|
1464 failed:
|
|
1465
|
|
1466 /* unlock name mutex */
|
|
1467
|
528
|
1468 ngx_resolver_free(r, name.data);
|
|
1469
|
350
|
1470 return;
|
|
1471 }
|
|
1472
|
|
1473
|
|
1474 static void
|
|
1475 ngx_resolver_process_ptr(ngx_resolver_t *r, u_char *buf, size_t n,
|
356
|
1476 ngx_uint_t ident, ngx_uint_t code, ngx_uint_t nan)
|
350
|
1477 {
|
|
1478 char *err;
|
|
1479 size_t len;
|
|
1480 in_addr_t addr;
|
650
|
1481 int32_t ttl;
|
350
|
1482 ngx_int_t digit;
|
|
1483 ngx_str_t name;
|
622
|
1484 ngx_uint_t i, mask, qident;
|
350
|
1485 ngx_resolver_an_t *an;
|
|
1486 ngx_resolver_ctx_t *ctx, *next;
|
|
1487 ngx_resolver_node_t *rn;
|
|
1488
|
|
1489 if (ngx_resolver_copy(r, NULL, buf, &buf[12], &buf[n]) != NGX_OK) {
|
|
1490 goto invalid_in_addr_arpa;
|
|
1491 }
|
|
1492
|
|
1493 addr = 0;
|
|
1494 i = 12;
|
|
1495
|
|
1496 for (mask = 0; mask < 32; mask += 8) {
|
|
1497 len = buf[i++];
|
|
1498
|
|
1499 digit = ngx_atoi(&buf[i], len);
|
|
1500 if (digit == NGX_ERROR || digit > 255) {
|
|
1501 goto invalid_in_addr_arpa;
|
|
1502 }
|
|
1503
|
|
1504 addr += digit << mask;
|
|
1505 i += len;
|
|
1506 }
|
|
1507
|
|
1508 if (ngx_strcmp(&buf[i], "\7in-addr\4arpa") != 0) {
|
|
1509 goto invalid_in_addr_arpa;
|
|
1510 }
|
|
1511
|
|
1512 /* lock addr mutex */
|
|
1513
|
|
1514 rn = ngx_resolver_lookup_addr(r, addr);
|
|
1515
|
|
1516 if (rn == NULL || rn->query == NULL) {
|
|
1517 ngx_log_error(r->log_level, r->log, 0,
|
|
1518 "unexpected response for %ud.%ud.%ud.%ud",
|
|
1519 (addr >> 24) & 0xff, (addr >> 16) & 0xff,
|
|
1520 (addr >> 8) & 0xff, addr & 0xff);
|
|
1521 goto failed;
|
|
1522 }
|
|
1523
|
|
1524 qident = (rn->query[0] << 8) + rn->query[1];
|
|
1525
|
|
1526 if (ident != qident) {
|
|
1527 ngx_log_error(r->log_level, r->log, 0,
|
372
|
1528 "wrong ident %ui response for %ud.%ud.%ud.%ud, expect %ui",
|
|
1529 ident, (addr >> 24) & 0xff, (addr >> 16) & 0xff,
|
|
1530 (addr >> 8) & 0xff, addr & 0xff, qident);
|
350
|
1531 goto failed;
|
|
1532 }
|
|
1533
|
356
|
1534 if (code == 0 && nan == 0) {
|
|
1535 code = 3; /* NXDOMAIN */
|
|
1536 }
|
|
1537
|
350
|
1538 if (code) {
|
|
1539 next = rn->waiting;
|
|
1540 rn->waiting = NULL;
|
|
1541
|
|
1542 ngx_queue_remove(&rn->queue);
|
|
1543
|
|
1544 ngx_rbtree_delete(&r->addr_rbtree, &rn->node);
|
|
1545
|
|
1546 ngx_resolver_free_node(r, rn);
|
|
1547
|
|
1548 /* unlock addr mutex */
|
|
1549
|
|
1550 while (next) {
|
|
1551 ctx = next;
|
|
1552 ctx->state = code;
|
|
1553 next = ctx->next;
|
|
1554
|
|
1555 ctx->handler(ctx);
|
|
1556 }
|
|
1557
|
|
1558 return;
|
|
1559 }
|
|
1560
|
|
1561 i += sizeof("\7in-addr\4arpa") + sizeof(ngx_resolver_qs_t);
|
|
1562
|
|
1563 if (i + 2 + sizeof(ngx_resolver_an_t) > (ngx_uint_t) n) {
|
|
1564 goto short_response;
|
|
1565 }
|
|
1566
|
|
1567 /* compression pointer to "XX.XX.XX.XX.in-addr.arpa */
|
|
1568
|
|
1569 if (buf[i] != 0xc0 || buf[i + 1] != 0x0c) {
|
|
1570 err = "invalid in-addr.arpa name in DNS response";
|
|
1571 goto invalid;
|
|
1572 }
|
|
1573
|
|
1574 an = (ngx_resolver_an_t *) &buf[i + 2];
|
|
1575
|
|
1576 len = (an->len_hi << 8) + an->len_lo;
|
650
|
1577 ttl = (an->ttl[0] << 24) + (an->ttl[1] << 16)
|
|
1578 + (an->ttl[2] << 8) + (an->ttl[3]);
|
|
1579
|
|
1580 if (ttl < 0) {
|
|
1581 ttl = 0;
|
|
1582 }
|
350
|
1583
|
|
1584 ngx_log_debug3(NGX_LOG_DEBUG_CORE, r->log, 0,
|
622
|
1585 "resolver qt:%ui cl:%ui len:%uz",
|
|
1586 (an->type_hi << 8) + an->type_lo,
|
|
1587 (an->class_hi << 8) + an->class_lo, len);
|
350
|
1588
|
|
1589 i += 2 + sizeof(ngx_resolver_an_t);
|
|
1590
|
|
1591 if (i + len > (ngx_uint_t) n) {
|
|
1592 goto short_response;
|
|
1593 }
|
|
1594
|
|
1595 if (ngx_resolver_copy(r, &name, buf, &buf[i], &buf[n]) != NGX_OK) {
|
|
1596 return;
|
|
1597 }
|
|
1598
|
|
1599 ngx_log_debug1(NGX_LOG_DEBUG_CORE, r->log, 0, "resolver an:%V", &name);
|
|
1600
|
442
|
1601 if (name.len != (size_t) rn->nlen
|
|
1602 || ngx_strncmp(name.data, rn->name, name.len) != 0)
|
350
|
1603 {
|
442
|
1604 if (rn->nlen) {
|
|
1605 ngx_resolver_free(r, rn->name);
|
|
1606 }
|
|
1607
|
|
1608 rn->nlen = (u_short) name.len;
|
350
|
1609 rn->name = name.data;
|
|
1610
|
442
|
1611 name.data = ngx_resolver_dup(r, rn->name, name.len);
|
350
|
1612 if (name.data == NULL) {
|
|
1613 goto failed;
|
|
1614 }
|
|
1615 }
|
|
1616
|
|
1617 ngx_queue_remove(&rn->queue);
|
|
1618
|
650
|
1619 rn->valid = ngx_time() + (r->valid ? r->valid : ttl);
|
350
|
1620 rn->expire = ngx_time() + r->expire;
|
|
1621
|
|
1622 ngx_queue_insert_head(&r->addr_expire_queue, &rn->queue);
|
|
1623
|
|
1624 next = rn->waiting;
|
|
1625 rn->waiting = NULL;
|
|
1626
|
|
1627 /* unlock addr mutex */
|
|
1628
|
|
1629 while (next) {
|
|
1630 ctx = next;
|
|
1631 ctx->state = NGX_OK;
|
|
1632 ctx->name = name;
|
|
1633 next = ctx->next;
|
|
1634
|
|
1635 ctx->handler(ctx);
|
|
1636 }
|
|
1637
|
|
1638 ngx_resolver_free(r, name.data);
|
|
1639
|
|
1640 return;
|
|
1641
|
|
1642 invalid_in_addr_arpa:
|
|
1643
|
|
1644 ngx_log_error(r->log_level, r->log, 0,
|
|
1645 "invalid in-addr.arpa name in DNS response");
|
|
1646 return;
|
|
1647
|
|
1648 short_response:
|
|
1649
|
|
1650 err = "short DNS response";
|
|
1651
|
|
1652 invalid:
|
|
1653
|
|
1654 /* unlock addr mutex */
|
|
1655
|
|
1656 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1657
|
|
1658 return;
|
|
1659
|
|
1660 failed:
|
|
1661
|
|
1662 /* unlock addr mutex */
|
|
1663
|
|
1664 return;
|
|
1665 }
|
|
1666
|
|
1667
|
|
1668 static ngx_resolver_node_t *
|
|
1669 ngx_resolver_lookup_name(ngx_resolver_t *r, ngx_str_t *name, uint32_t hash)
|
|
1670 {
|
|
1671 ngx_int_t rc;
|
|
1672 ngx_rbtree_node_t *node, *sentinel;
|
|
1673 ngx_resolver_node_t *rn;
|
|
1674
|
|
1675 node = r->name_rbtree.root;
|
|
1676 sentinel = r->name_rbtree.sentinel;
|
|
1677
|
|
1678 while (node != sentinel) {
|
|
1679
|
|
1680 if (hash < node->key) {
|
|
1681 node = node->left;
|
|
1682 continue;
|
|
1683 }
|
|
1684
|
|
1685 if (hash > node->key) {
|
|
1686 node = node->right;
|
|
1687 continue;
|
|
1688 }
|
|
1689
|
|
1690 /* hash == node->key */
|
|
1691
|
664
|
1692 rn = (ngx_resolver_node_t *) node;
|
|
1693
|
|
1694 rc = ngx_memn2cmp(name->data, rn->name, name->len, rn->nlen);
|
|
1695
|
|
1696 if (rc == 0) {
|
|
1697 return rn;
|
|
1698 }
|
|
1699
|
|
1700 node = (rc < 0) ? node->left : node->right;
|
350
|
1701 }
|
|
1702
|
|
1703 /* not found */
|
|
1704
|
|
1705 return NULL;
|
|
1706 }
|
|
1707
|
|
1708
|
|
1709 static ngx_resolver_node_t *
|
|
1710 ngx_resolver_lookup_addr(ngx_resolver_t *r, in_addr_t addr)
|
|
1711 {
|
|
1712 ngx_rbtree_node_t *node, *sentinel;
|
|
1713
|
|
1714 node = r->addr_rbtree.root;
|
|
1715 sentinel = r->addr_rbtree.sentinel;
|
|
1716
|
|
1717 while (node != sentinel) {
|
|
1718
|
|
1719 if (addr < node->key) {
|
|
1720 node = node->left;
|
|
1721 continue;
|
|
1722 }
|
|
1723
|
|
1724 if (addr > node->key) {
|
|
1725 node = node->right;
|
|
1726 continue;
|
|
1727 }
|
|
1728
|
|
1729 /* addr == node->key */
|
|
1730
|
|
1731 return (ngx_resolver_node_t *) node;
|
|
1732 }
|
|
1733
|
|
1734 /* not found */
|
|
1735
|
|
1736 return NULL;
|
|
1737 }
|
|
1738
|
|
1739
|
|
1740 static void
|
|
1741 ngx_resolver_rbtree_insert_value(ngx_rbtree_node_t *temp,
|
|
1742 ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel)
|
|
1743 {
|
|
1744 ngx_rbtree_node_t **p;
|
|
1745 ngx_resolver_node_t *rn, *rn_temp;
|
|
1746
|
|
1747 for ( ;; ) {
|
|
1748
|
|
1749 if (node->key < temp->key) {
|
|
1750
|
|
1751 p = &temp->left;
|
|
1752
|
|
1753 } else if (node->key > temp->key) {
|
|
1754
|
|
1755 p = &temp->right;
|
|
1756
|
|
1757 } else { /* node->key == temp->key */
|
|
1758
|
|
1759 rn = (ngx_resolver_node_t *) node;
|
|
1760 rn_temp = (ngx_resolver_node_t *) temp;
|
|
1761
|
528
|
1762 p = (ngx_memn2cmp(rn->name, rn_temp->name, rn->nlen, rn_temp->nlen)
|
|
1763 < 0) ? &temp->left : &temp->right;
|
350
|
1764 }
|
|
1765
|
|
1766 if (*p == sentinel) {
|
|
1767 break;
|
|
1768 }
|
|
1769
|
|
1770 temp = *p;
|
|
1771 }
|
|
1772
|
|
1773 *p = node;
|
|
1774 node->parent = temp;
|
|
1775 node->left = sentinel;
|
|
1776 node->right = sentinel;
|
|
1777 ngx_rbt_red(node);
|
|
1778 }
|
|
1779
|
|
1780
|
|
1781 static ngx_int_t
|
|
1782 ngx_resolver_create_name_query(ngx_resolver_node_t *rn, ngx_resolver_ctx_t *ctx)
|
|
1783 {
|
|
1784 u_char *p, *s;
|
544
|
1785 size_t len, nlen;
|
350
|
1786 ngx_uint_t ident;
|
|
1787 ngx_resolver_qs_t *qs;
|
|
1788 ngx_resolver_query_t *query;
|
|
1789
|
544
|
1790 nlen = ctx->name.len ? (1 + ctx->name.len + 1) : 1;
|
|
1791
|
|
1792 len = sizeof(ngx_resolver_query_t) + nlen + sizeof(ngx_resolver_qs_t);
|
|
1793
|
|
1794 p = ngx_resolver_alloc(ctx->resolver, len);
|
350
|
1795 if (p == NULL) {
|
|
1796 return NGX_ERROR;
|
|
1797 }
|
|
1798
|
|
1799 rn->qlen = (u_short) len;
|
|
1800 rn->query = p;
|
|
1801
|
|
1802 query = (ngx_resolver_query_t *) p;
|
|
1803
|
|
1804 ident = ngx_random();
|
|
1805
|
|
1806 ngx_log_debug2(NGX_LOG_DEBUG_CORE, ctx->resolver->log, 0,
|
|
1807 "resolve: \"%V\" %i", &ctx->name, ident & 0xffff);
|
|
1808
|
|
1809 query->ident_hi = (u_char) ((ident >> 8) & 0xff);
|
|
1810 query->ident_lo = (u_char) (ident & 0xff);
|
|
1811
|
|
1812 /* recursion query */
|
|
1813 query->flags_hi = 1; query->flags_lo = 0;
|
|
1814
|
|
1815 /* one question */
|
|
1816 query->nqs_hi = 0; query->nqs_lo = 1;
|
|
1817 query->nan_hi = 0; query->nan_lo = 0;
|
|
1818 query->nns_hi = 0; query->nns_lo = 0;
|
|
1819 query->nar_hi = 0; query->nar_lo = 0;
|
|
1820
|
544
|
1821 p += sizeof(ngx_resolver_query_t) + nlen;
|
350
|
1822
|
|
1823 qs = (ngx_resolver_qs_t *) p;
|
|
1824
|
|
1825 /* query type */
|
|
1826 qs->type_hi = 0; qs->type_lo = (u_char) ctx->type;
|
|
1827
|
|
1828 /* IP query class */
|
|
1829 qs->class_hi = 0; qs->class_lo = 1;
|
|
1830
|
|
1831 /* convert "www.example.com" to "\3www\7example\3com\0" */
|
|
1832
|
|
1833 len = 0;
|
|
1834 p--;
|
|
1835 *p-- = '\0';
|
|
1836
|
|
1837 for (s = ctx->name.data + ctx->name.len - 1; s >= ctx->name.data; s--) {
|
|
1838 if (*s != '.') {
|
|
1839 *p = *s;
|
|
1840 len++;
|
|
1841
|
|
1842 } else {
|
372
|
1843 if (len == 0) {
|
|
1844 return NGX_DECLINED;
|
|
1845 }
|
|
1846
|
350
|
1847 *p = (u_char) len;
|
|
1848 len = 0;
|
|
1849 }
|
|
1850
|
|
1851 p--;
|
|
1852 }
|
|
1853
|
|
1854 *p = (u_char) len;
|
|
1855
|
|
1856 return NGX_OK;
|
|
1857 }
|
|
1858
|
|
1859
|
|
1860 /* AF_INET only */
|
|
1861
|
|
1862 static ngx_int_t
|
|
1863 ngx_resolver_create_addr_query(ngx_resolver_node_t *rn, ngx_resolver_ctx_t *ctx)
|
|
1864 {
|
|
1865 u_char *p, *d;
|
|
1866 size_t len;
|
|
1867 ngx_int_t n;
|
|
1868 ngx_uint_t ident;
|
|
1869 ngx_resolver_query_t *query;
|
|
1870
|
|
1871 len = sizeof(ngx_resolver_query_t)
|
|
1872 + sizeof(".255.255.255.255.in-addr.arpa.") - 1
|
|
1873 + sizeof(ngx_resolver_qs_t);
|
|
1874
|
544
|
1875 p = ngx_resolver_alloc(ctx->resolver, len);
|
350
|
1876 if (p == NULL) {
|
|
1877 return NGX_ERROR;
|
|
1878 }
|
|
1879
|
|
1880 rn->query = p;
|
|
1881 query = (ngx_resolver_query_t *) p;
|
|
1882
|
|
1883 ident = ngx_random();
|
|
1884
|
|
1885 query->ident_hi = (u_char) ((ident >> 8) & 0xff);
|
|
1886 query->ident_lo = (u_char) (ident & 0xff);
|
|
1887
|
|
1888 /* recursion query */
|
|
1889 query->flags_hi = 1; query->flags_lo = 0;
|
|
1890
|
|
1891 /* one question */
|
|
1892 query->nqs_hi = 0; query->nqs_lo = 1;
|
|
1893 query->nan_hi = 0; query->nan_lo = 0;
|
|
1894 query->nns_hi = 0; query->nns_lo = 0;
|
|
1895 query->nar_hi = 0; query->nar_lo = 0;
|
|
1896
|
|
1897 p += sizeof(ngx_resolver_query_t);
|
|
1898
|
582
|
1899 for (n = 0; n < 32; n += 8) {
|
350
|
1900 d = ngx_sprintf(&p[1], "%ud", (ctx->addr >> n) & 0xff);
|
|
1901 *p = (u_char) (d - &p[1]);
|
|
1902 p = d;
|
|
1903 }
|
|
1904
|
|
1905 /* query type "PTR", IP query class */
|
|
1906 ngx_memcpy(p, "\7in-addr\4arpa\0\0\14\0\1", 18);
|
|
1907
|
|
1908 rn->qlen = (u_short)
|
|
1909 (p + sizeof("\7in-addr\4arpa") + sizeof(ngx_resolver_qs_t)
|
|
1910 - rn->query);
|
|
1911
|
|
1912 return NGX_OK;
|
|
1913 }
|
|
1914
|
|
1915
|
|
1916 static ngx_int_t
|
|
1917 ngx_resolver_copy(ngx_resolver_t *r, ngx_str_t *name, u_char *buf, u_char *src,
|
|
1918 u_char *last)
|
|
1919 {
|
|
1920 char *err;
|
|
1921 u_char *p, *dst;
|
|
1922 ssize_t len;
|
|
1923 ngx_uint_t i, n;
|
|
1924
|
|
1925 p = src;
|
|
1926 len = -1;
|
|
1927
|
|
1928 /*
|
|
1929 * compression pointers allow to create endless loop, so we set limit;
|
|
1930 * 128 pointers should be enough to store 255-byte name
|
|
1931 */
|
|
1932
|
|
1933 for (i = 0; i < 128; i++) {
|
|
1934 n = *p++;
|
|
1935
|
|
1936 if (n == 0) {
|
|
1937 goto done;
|
|
1938 }
|
|
1939
|
|
1940 if (n & 0xc0) {
|
420
|
1941 n = ((n & 0x3f) << 8) + *p;
|
350
|
1942 p = &buf[n];
|
|
1943
|
|
1944 } else {
|
|
1945 len += 1 + n;
|
|
1946 p = &p[n];
|
|
1947 }
|
|
1948
|
|
1949 if (p >= last) {
|
|
1950 err = "name is out of response";
|
|
1951 goto invalid;
|
|
1952 }
|
|
1953 }
|
|
1954
|
|
1955 err = "compression pointers loop";
|
|
1956
|
|
1957 invalid:
|
|
1958
|
|
1959 ngx_log_error(r->log_level, r->log, 0, err);
|
|
1960
|
|
1961 return NGX_ERROR;
|
|
1962
|
|
1963 done:
|
|
1964
|
|
1965 if (name == NULL) {
|
|
1966 return NGX_OK;
|
|
1967 }
|
|
1968
|
542
|
1969 if (len == -1) {
|
|
1970 name->len = 0;
|
|
1971 name->data = NULL;
|
|
1972 return NGX_OK;
|
|
1973 }
|
|
1974
|
350
|
1975 dst = ngx_resolver_alloc(r, len);
|
|
1976 if (dst == NULL) {
|
|
1977 return NGX_ERROR;
|
|
1978 }
|
|
1979
|
|
1980 name->data = dst;
|
|
1981
|
|
1982 n = *src++;
|
|
1983
|
|
1984 for ( ;; ) {
|
648
|
1985 if (n & 0xc0) {
|
|
1986 n = ((n & 0x3f) << 8) + *src;
|
|
1987 src = &buf[n];
|
|
1988
|
|
1989 n = *src++;
|
|
1990
|
|
1991 } else {
|
350
|
1992 ngx_memcpy(dst, src, n);
|
|
1993 dst += n;
|
|
1994 src += n;
|
|
1995
|
|
1996 n = *src++;
|
|
1997
|
|
1998 if (n != 0) {
|
|
1999 *dst++ = '.';
|
|
2000 }
|
|
2001 }
|
|
2002
|
|
2003 if (n == 0) {
|
|
2004 name->len = dst - name->data;
|
|
2005 return NGX_OK;
|
|
2006 }
|
|
2007 }
|
|
2008 }
|
|
2009
|
|
2010
|
|
2011 static void
|
|
2012 ngx_resolver_timeout_handler(ngx_event_t *ev)
|
|
2013 {
|
|
2014 ngx_resolver_ctx_t *ctx;
|
|
2015
|
|
2016 ctx = ev->data;
|
|
2017
|
|
2018 ctx->state = NGX_RESOLVE_TIMEDOUT;
|
|
2019
|
|
2020 ctx->handler(ctx);
|
|
2021 }
|
|
2022
|
|
2023
|
|
2024 static void
|
|
2025 ngx_resolver_free_node(ngx_resolver_t *r, ngx_resolver_node_t *rn)
|
|
2026 {
|
|
2027 /* lock alloc mutex */
|
|
2028
|
|
2029 if (rn->query) {
|
|
2030 ngx_resolver_free_locked(r, rn->query);
|
|
2031 }
|
|
2032
|
|
2033 if (rn->name) {
|
|
2034 ngx_resolver_free_locked(r, rn->name);
|
|
2035 }
|
|
2036
|
|
2037 if (rn->cnlen) {
|
|
2038 ngx_resolver_free_locked(r, rn->u.cname);
|
|
2039 }
|
|
2040
|
|
2041 if (rn->naddrs > 1) {
|
|
2042 ngx_resolver_free_locked(r, rn->u.addrs);
|
|
2043 }
|
|
2044
|
|
2045 ngx_resolver_free_locked(r, rn);
|
|
2046
|
|
2047 /* unlock alloc mutex */
|
|
2048 }
|
|
2049
|
|
2050
|
|
2051 static void *
|
|
2052 ngx_resolver_alloc(ngx_resolver_t *r, size_t size)
|
|
2053 {
|
|
2054 u_char *p;
|
|
2055
|
|
2056 /* lock alloc mutex */
|
|
2057
|
|
2058 p = ngx_alloc(size, r->log);
|
|
2059
|
|
2060 /* unlock alloc mutex */
|
|
2061
|
|
2062 return p;
|
|
2063 }
|
|
2064
|
|
2065
|
366
|
2066 static void *
|
350
|
2067 ngx_resolver_calloc(ngx_resolver_t *r, size_t size)
|
|
2068 {
|
|
2069 u_char *p;
|
|
2070
|
|
2071 p = ngx_resolver_alloc(r, size);
|
|
2072
|
|
2073 if (p) {
|
|
2074 ngx_memzero(p, size);
|
|
2075 }
|
|
2076
|
|
2077 return p;
|
|
2078 }
|
|
2079
|
|
2080
|
|
2081 static void
|
|
2082 ngx_resolver_free(ngx_resolver_t *r, void *p)
|
|
2083 {
|
|
2084 /* lock alloc mutex */
|
|
2085
|
|
2086 ngx_free(p);
|
|
2087
|
|
2088 /* unlock alloc mutex */
|
|
2089 }
|
|
2090
|
|
2091
|
|
2092 static void
|
|
2093 ngx_resolver_free_locked(ngx_resolver_t *r, void *p)
|
|
2094 {
|
|
2095 ngx_free(p);
|
|
2096 }
|
|
2097
|
|
2098
|
|
2099 static void *
|
|
2100 ngx_resolver_dup(ngx_resolver_t *r, void *src, size_t size)
|
|
2101 {
|
|
2102 void *dst;
|
|
2103
|
|
2104 dst = ngx_resolver_alloc(r, size);
|
|
2105
|
|
2106 if (dst == NULL) {
|
|
2107 return dst;
|
|
2108 }
|
|
2109
|
|
2110 ngx_memcpy(dst, src, size);
|
|
2111
|
|
2112 return dst;
|
|
2113 }
|
|
2114
|
|
2115
|
|
2116 char *
|
|
2117 ngx_resolver_strerror(ngx_int_t err)
|
|
2118 {
|
|
2119 static char *errors[] = {
|
|
2120 "Format error", /* FORMERR */
|
|
2121 "Server failure", /* SERVFAIL */
|
|
2122 "Host not found", /* NXDOMAIN */
|
|
2123 "Unimplemented", /* NOTIMP */
|
|
2124 "Operation refused" /* REFUSED */
|
|
2125 };
|
|
2126
|
|
2127 if (err > 0 && err < 6) {
|
|
2128 return errors[err - 1];
|
|
2129 }
|
|
2130
|
|
2131 if (err == NGX_RESOLVE_TIMEDOUT) {
|
|
2132 return "Operation timed out";
|
|
2133 }
|
|
2134
|
|
2135 return "Unknown error";
|
|
2136 }
|
|
2137
|
|
2138
|
560
|
2139 static u_char *
|
|
2140 ngx_resolver_log_error(ngx_log_t *log, u_char *buf, size_t len)
|
|
2141 {
|
|
2142 u_char *p;
|
|
2143 ngx_udp_connection_t *uc;
|
|
2144
|
|
2145 p = buf;
|
|
2146
|
|
2147 if (log->action) {
|
|
2148 p = ngx_snprintf(buf, len, " while %s", log->action);
|
|
2149 len -= p - buf;
|
|
2150 }
|
|
2151
|
|
2152 uc = log->data;
|
|
2153
|
|
2154 if (uc) {
|
|
2155 p = ngx_snprintf(p, len, ", resolver: %V", &uc->server);
|
|
2156 }
|
|
2157
|
|
2158 return p;
|
|
2159 }
|
|
2160
|
|
2161
|
350
|
2162 ngx_int_t
|
|
2163 ngx_udp_connect(ngx_udp_connection_t *uc)
|
|
2164 {
|
|
2165 int rc;
|
|
2166 ngx_int_t event;
|
|
2167 ngx_event_t *rev, *wev;
|
|
2168 ngx_socket_t s;
|
|
2169 ngx_connection_t *c;
|
|
2170
|
|
2171 s = ngx_socket(AF_INET, SOCK_DGRAM, 0);
|
|
2172
|
560
|
2173 ngx_log_debug1(NGX_LOG_DEBUG_EVENT, &uc->log, 0, "UDP socket %d", s);
|
350
|
2174
|
|
2175 if (s == -1) {
|
560
|
2176 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2177 ngx_socket_n " failed");
|
|
2178 return NGX_ERROR;
|
|
2179 }
|
|
2180
|
560
|
2181 c = ngx_get_connection(s, &uc->log);
|
350
|
2182
|
|
2183 if (c == NULL) {
|
|
2184 if (ngx_close_socket(s) == -1) {
|
560
|
2185 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2186 ngx_close_socket_n "failed");
|
|
2187 }
|
|
2188
|
|
2189 return NGX_ERROR;
|
|
2190 }
|
|
2191
|
|
2192 if (ngx_nonblocking(s) == -1) {
|
560
|
2193 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2194 ngx_nonblocking_n " failed");
|
|
2195
|
|
2196 ngx_free_connection(c);
|
|
2197
|
|
2198 if (ngx_close_socket(s) == -1) {
|
560
|
2199 ngx_log_error(NGX_LOG_ALERT, &uc->log, ngx_socket_errno,
|
350
|
2200 ngx_close_socket_n " failed");
|
|
2201 }
|
|
2202
|
|
2203 return NGX_ERROR;
|
|
2204 }
|
|
2205
|
|
2206 rev = c->read;
|
|
2207 wev = c->write;
|
|
2208
|
560
|
2209 rev->log = &uc->log;
|
|
2210 wev->log = &uc->log;
|
350
|
2211
|
|
2212 uc->connection = c;
|
|
2213
|
|
2214 c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1);
|
|
2215
|
|
2216 #if (NGX_THREADS)
|
|
2217
|
|
2218 /* TODO: lock event when call completion handler */
|
|
2219
|
|
2220 rev->lock = &c->lock;
|
|
2221 wev->lock = &c->lock;
|
|
2222 rev->own_lock = &c->lock;
|
|
2223 wev->own_lock = &c->lock;
|
|
2224
|
|
2225 #endif
|
|
2226
|
560
|
2227 ngx_log_debug3(NGX_LOG_DEBUG_EVENT, &uc->log, 0,
|
350
|
2228 "connect to %V, fd:%d #%d", &uc->server, s, c->number);
|
|
2229
|
|
2230 rc = connect(s, uc->sockaddr, uc->socklen);
|
|
2231
|
|
2232 /* TODO: aio, iocp */
|
|
2233
|
|
2234 if (rc == -1) {
|
560
|
2235 ngx_log_error(NGX_LOG_CRIT, &uc->log, ngx_socket_errno,
|
|
2236 "connect() failed");
|
350
|
2237
|
|
2238 return NGX_ERROR;
|
|
2239 }
|
|
2240
|
|
2241 /* UDP sockets are always ready to write */
|
|
2242 wev->ready = 1;
|
|
2243
|
|
2244 if (ngx_add_event) {
|
|
2245
|
|
2246 event = (ngx_event_flags & NGX_USE_CLEAR_EVENT) ?
|
|
2247 /* kqueue, epoll */ NGX_CLEAR_EVENT:
|
|
2248 /* select, poll, /dev/poll */ NGX_LEVEL_EVENT;
|
|
2249 /* eventport event type has no meaning: oneshot only */
|
|
2250
|
|
2251 if (ngx_add_event(rev, NGX_READ_EVENT, event) != NGX_OK) {
|
|
2252 return NGX_ERROR;
|
|
2253 }
|
|
2254
|
|
2255 } else {
|
|
2256 /* rtsig */
|
|
2257
|
|
2258 if (ngx_add_conn(c) == NGX_ERROR) {
|
|
2259 return NGX_ERROR;
|
|
2260 }
|
|
2261 }
|
|
2262
|
|
2263 return NGX_OK;
|
|
2264 }
|