.. | .. |
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| 1 | +// SPDX-License-Identifier: GPL-2.0-or-later |
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1 | 2 | /* Server address list management |
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2 | 3 | * |
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3 | 4 | * Copyright (C) 2017 Red Hat, Inc. All Rights Reserved. |
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4 | 5 | * Written by David Howells (dhowells@redhat.com) |
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5 | | - * |
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6 | | - * This program is free software; you can redistribute it and/or |
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7 | | - * modify it under the terms of the GNU General Public Licence |
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8 | | - * as published by the Free Software Foundation; either version |
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9 | | - * 2 of the Licence, or (at your option) any later version. |
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10 | 6 | */ |
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11 | 7 | |
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12 | 8 | #include <linux/slab.h> |
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.. | .. |
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17 | 13 | #include "internal.h" |
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18 | 14 | #include "afs_fs.h" |
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19 | 15 | |
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20 | | -//#define AFS_MAX_ADDRESSES |
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21 | | -// ((unsigned int)((PAGE_SIZE - sizeof(struct afs_addr_list)) / |
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22 | | -// sizeof(struct sockaddr_rxrpc))) |
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23 | | -#define AFS_MAX_ADDRESSES ((unsigned int)(sizeof(unsigned long) * 8)) |
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24 | | - |
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25 | 16 | /* |
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26 | 17 | * Release an address list. |
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27 | 18 | */ |
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28 | 19 | void afs_put_addrlist(struct afs_addr_list *alist) |
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29 | 20 | { |
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30 | 21 | if (alist && refcount_dec_and_test(&alist->usage)) |
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31 | | - call_rcu(&alist->rcu, (rcu_callback_t)kfree); |
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| 22 | + kfree_rcu(alist, rcu); |
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32 | 23 | } |
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33 | 24 | |
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34 | 25 | /* |
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.. | .. |
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43 | 34 | |
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44 | 35 | _enter("%u,%u,%u", nr, service, port); |
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45 | 36 | |
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| 37 | + if (nr > AFS_MAX_ADDRESSES) |
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| 38 | + nr = AFS_MAX_ADDRESSES; |
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| 39 | + |
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46 | 40 | alist = kzalloc(struct_size(alist, addrs, nr), GFP_KERNEL); |
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47 | 41 | if (!alist) |
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48 | 42 | return NULL; |
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49 | 43 | |
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50 | 44 | refcount_set(&alist->usage, 1); |
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| 45 | + alist->max_addrs = nr; |
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51 | 46 | |
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52 | 47 | for (i = 0; i < nr; i++) { |
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53 | 48 | struct sockaddr_rxrpc *srx = &alist->addrs[i]; |
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.. | .. |
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65 | 60 | /* |
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66 | 61 | * Parse a text string consisting of delimited addresses. |
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67 | 62 | */ |
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68 | | -struct afs_addr_list *afs_parse_text_addrs(const char *text, size_t len, |
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69 | | - char delim, |
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70 | | - unsigned short service, |
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71 | | - unsigned short port) |
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| 63 | +struct afs_vlserver_list *afs_parse_text_addrs(struct afs_net *net, |
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| 64 | + const char *text, size_t len, |
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| 65 | + char delim, |
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| 66 | + unsigned short service, |
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| 67 | + unsigned short port) |
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72 | 68 | { |
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| 69 | + struct afs_vlserver_list *vllist; |
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73 | 70 | struct afs_addr_list *alist; |
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74 | 71 | const char *p, *end = text + len; |
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| 72 | + const char *problem; |
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75 | 73 | unsigned int nr = 0; |
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| 74 | + int ret = -ENOMEM; |
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76 | 75 | |
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77 | 76 | _enter("%*.*s,%c", (int)len, (int)len, text, delim); |
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78 | 77 | |
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79 | | - if (!len) |
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| 78 | + if (!len) { |
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| 79 | + _leave(" = -EDESTADDRREQ [empty]"); |
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80 | 80 | return ERR_PTR(-EDESTADDRREQ); |
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| 81 | + } |
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81 | 82 | |
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82 | 83 | if (delim == ':' && (memchr(text, ',', len) || !memchr(text, '.', len))) |
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83 | 84 | delim = ','; |
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.. | .. |
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85 | 86 | /* Count the addresses */ |
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86 | 87 | p = text; |
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87 | 88 | do { |
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88 | | - if (!*p) |
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89 | | - return ERR_PTR(-EINVAL); |
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| 89 | + if (!*p) { |
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| 90 | + problem = "nul"; |
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| 91 | + goto inval; |
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| 92 | + } |
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90 | 93 | if (*p == delim) |
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91 | 94 | continue; |
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92 | 95 | nr++; |
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93 | 96 | if (*p == '[') { |
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94 | 97 | p++; |
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95 | | - if (p == end) |
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96 | | - return ERR_PTR(-EINVAL); |
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| 98 | + if (p == end) { |
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| 99 | + problem = "brace1"; |
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| 100 | + goto inval; |
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| 101 | + } |
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97 | 102 | p = memchr(p, ']', end - p); |
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98 | | - if (!p) |
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99 | | - return ERR_PTR(-EINVAL); |
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| 103 | + if (!p) { |
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| 104 | + problem = "brace2"; |
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| 105 | + goto inval; |
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| 106 | + } |
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100 | 107 | p++; |
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101 | 108 | if (p >= end) |
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102 | 109 | break; |
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.. | .. |
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109 | 116 | } while (p < end); |
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110 | 117 | |
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111 | 118 | _debug("%u/%u addresses", nr, AFS_MAX_ADDRESSES); |
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112 | | - if (nr > AFS_MAX_ADDRESSES) |
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113 | | - nr = AFS_MAX_ADDRESSES; |
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114 | 119 | |
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115 | | - alist = afs_alloc_addrlist(nr, service, port); |
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116 | | - if (!alist) |
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| 120 | + vllist = afs_alloc_vlserver_list(1); |
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| 121 | + if (!vllist) |
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117 | 122 | return ERR_PTR(-ENOMEM); |
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| 123 | + |
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| 124 | + vllist->nr_servers = 1; |
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| 125 | + vllist->servers[0].server = afs_alloc_vlserver("<dummy>", 7, AFS_VL_PORT); |
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| 126 | + if (!vllist->servers[0].server) |
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| 127 | + goto error_vl; |
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| 128 | + |
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| 129 | + alist = afs_alloc_addrlist(nr, service, AFS_VL_PORT); |
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| 130 | + if (!alist) |
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| 131 | + goto error; |
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118 | 132 | |
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119 | 133 | /* Extract the addresses */ |
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120 | 134 | p = text; |
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121 | 135 | do { |
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122 | | - struct sockaddr_rxrpc *srx = &alist->addrs[alist->nr_addrs]; |
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123 | 136 | const char *q, *stop; |
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| 137 | + unsigned int xport = port; |
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| 138 | + __be32 x[4]; |
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| 139 | + int family; |
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124 | 140 | |
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125 | 141 | if (*p == delim) { |
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126 | 142 | p++; |
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.. | .. |
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136 | 152 | break; |
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137 | 153 | } |
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138 | 154 | |
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139 | | - if (in4_pton(p, q - p, |
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140 | | - (u8 *)&srx->transport.sin6.sin6_addr.s6_addr32[3], |
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141 | | - -1, &stop)) { |
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142 | | - srx->transport.sin6.sin6_addr.s6_addr32[0] = 0; |
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143 | | - srx->transport.sin6.sin6_addr.s6_addr32[1] = 0; |
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144 | | - srx->transport.sin6.sin6_addr.s6_addr32[2] = htonl(0xffff); |
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145 | | - } else if (in6_pton(p, q - p, |
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146 | | - srx->transport.sin6.sin6_addr.s6_addr, |
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147 | | - -1, &stop)) { |
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148 | | - /* Nothing to do */ |
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| 155 | + if (in4_pton(p, q - p, (u8 *)&x[0], -1, &stop)) { |
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| 156 | + family = AF_INET; |
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| 157 | + } else if (in6_pton(p, q - p, (u8 *)x, -1, &stop)) { |
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| 158 | + family = AF_INET6; |
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149 | 159 | } else { |
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| 160 | + problem = "family"; |
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150 | 161 | goto bad_address; |
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151 | 162 | } |
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152 | 163 | |
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153 | | - if (stop != q) |
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154 | | - goto bad_address; |
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155 | | - |
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156 | 164 | p = q; |
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| 165 | + if (stop != p) { |
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| 166 | + problem = "nostop"; |
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| 167 | + goto bad_address; |
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| 168 | + } |
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| 169 | + |
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157 | 170 | if (q < end && *q == ']') |
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158 | 171 | p++; |
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159 | 172 | |
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160 | 173 | if (p < end) { |
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161 | 174 | if (*p == '+') { |
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162 | 175 | /* Port number specification "+1234" */ |
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163 | | - unsigned int xport = 0; |
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| 176 | + xport = 0; |
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164 | 177 | p++; |
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165 | | - if (p >= end || !isdigit(*p)) |
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| 178 | + if (p >= end || !isdigit(*p)) { |
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| 179 | + problem = "port"; |
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166 | 180 | goto bad_address; |
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| 181 | + } |
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167 | 182 | do { |
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168 | 183 | xport *= 10; |
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169 | 184 | xport += *p - '0'; |
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170 | | - if (xport > 65535) |
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| 185 | + if (xport > 65535) { |
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| 186 | + problem = "pval"; |
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171 | 187 | goto bad_address; |
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| 188 | + } |
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172 | 189 | p++; |
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173 | 190 | } while (p < end && isdigit(*p)); |
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174 | | - srx->transport.sin6.sin6_port = htons(xport); |
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175 | 191 | } else if (*p == delim) { |
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176 | 192 | p++; |
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177 | 193 | } else { |
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| 194 | + problem = "weird"; |
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178 | 195 | goto bad_address; |
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179 | 196 | } |
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180 | 197 | } |
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181 | 198 | |
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182 | | - alist->nr_addrs++; |
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183 | | - } while (p < end && alist->nr_addrs < AFS_MAX_ADDRESSES); |
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| 199 | + if (family == AF_INET) |
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| 200 | + afs_merge_fs_addr4(alist, x[0], xport); |
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| 201 | + else |
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| 202 | + afs_merge_fs_addr6(alist, x, xport); |
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184 | 203 | |
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| 204 | + } while (p < end); |
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| 205 | + |
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| 206 | + rcu_assign_pointer(vllist->servers[0].server->addresses, alist); |
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185 | 207 | _leave(" = [nr %u]", alist->nr_addrs); |
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186 | | - return alist; |
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| 208 | + return vllist; |
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187 | 209 | |
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188 | | -bad_address: |
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189 | | - kfree(alist); |
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| 210 | +inval: |
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| 211 | + _leave(" = -EINVAL [%s %zu %*.*s]", |
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| 212 | + problem, p - text, (int)len, (int)len, text); |
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190 | 213 | return ERR_PTR(-EINVAL); |
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| 214 | +bad_address: |
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| 215 | + _leave(" = -EINVAL [%s %zu %*.*s]", |
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| 216 | + problem, p - text, (int)len, (int)len, text); |
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| 217 | + ret = -EINVAL; |
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| 218 | +error: |
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| 219 | + afs_put_addrlist(alist); |
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| 220 | +error_vl: |
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| 221 | + afs_put_vlserverlist(net, vllist); |
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| 222 | + return ERR_PTR(ret); |
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191 | 223 | } |
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192 | 224 | |
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193 | 225 | /* |
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.. | .. |
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206 | 238 | /* |
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207 | 239 | * Perform a DNS query for VL servers and build a up an address list. |
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208 | 240 | */ |
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209 | | -struct afs_addr_list *afs_dns_query(struct afs_cell *cell, time64_t *_expiry) |
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| 241 | +struct afs_vlserver_list *afs_dns_query(struct afs_cell *cell, time64_t *_expiry) |
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210 | 242 | { |
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211 | | - struct afs_addr_list *alist; |
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212 | | - char *vllist = NULL; |
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| 243 | + struct afs_vlserver_list *vllist; |
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| 244 | + char *result = NULL; |
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213 | 245 | int ret; |
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214 | 246 | |
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215 | 247 | _enter("%s", cell->name); |
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216 | 248 | |
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217 | | - ret = dns_query("afsdb", cell->name, cell->name_len, |
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218 | | - "", &vllist, _expiry); |
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219 | | - if (ret < 0) |
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| 249 | + ret = dns_query(cell->net->net, "afsdb", cell->name, cell->name_len, |
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| 250 | + "srv=1", &result, _expiry, true); |
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| 251 | + if (ret < 0) { |
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| 252 | + _leave(" = %d [dns]", ret); |
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220 | 253 | return ERR_PTR(ret); |
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221 | | - |
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222 | | - alist = afs_parse_text_addrs(vllist, strlen(vllist), ',', |
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223 | | - VL_SERVICE, AFS_VL_PORT); |
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224 | | - if (IS_ERR(alist)) { |
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225 | | - kfree(vllist); |
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226 | | - if (alist != ERR_PTR(-ENOMEM)) |
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227 | | - pr_err("Failed to parse DNS data\n"); |
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228 | | - return alist; |
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229 | 254 | } |
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230 | 255 | |
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231 | | - kfree(vllist); |
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232 | | - return alist; |
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| 256 | + if (*_expiry == 0) |
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| 257 | + *_expiry = ktime_get_real_seconds() + 60; |
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| 258 | + |
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| 259 | + if (ret > 1 && result[0] == 0) |
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| 260 | + vllist = afs_extract_vlserver_list(cell, result, ret); |
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| 261 | + else |
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| 262 | + vllist = afs_parse_text_addrs(cell->net, result, ret, ',', |
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| 263 | + VL_SERVICE, AFS_VL_PORT); |
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| 264 | + kfree(result); |
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| 265 | + if (IS_ERR(vllist) && vllist != ERR_PTR(-ENOMEM)) |
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| 266 | + pr_err("Failed to parse DNS data %ld\n", PTR_ERR(vllist)); |
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| 267 | + |
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| 268 | + return vllist; |
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233 | 269 | } |
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234 | 270 | |
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235 | 271 | /* |
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.. | .. |
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237 | 273 | */ |
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238 | 274 | void afs_merge_fs_addr4(struct afs_addr_list *alist, __be32 xdr, u16 port) |
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239 | 275 | { |
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240 | | - struct sockaddr_in6 *a; |
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241 | | - __be16 xport = htons(port); |
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| 276 | + struct sockaddr_rxrpc *srx; |
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| 277 | + u32 addr = ntohl(xdr); |
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242 | 278 | int i; |
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243 | 279 | |
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| 280 | + if (alist->nr_addrs >= alist->max_addrs) |
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| 281 | + return; |
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| 282 | + |
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244 | 283 | for (i = 0; i < alist->nr_ipv4; i++) { |
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245 | | - a = &alist->addrs[i].transport.sin6; |
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246 | | - if (xdr == a->sin6_addr.s6_addr32[3] && |
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247 | | - xport == a->sin6_port) |
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| 284 | + struct sockaddr_in *a = &alist->addrs[i].transport.sin; |
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| 285 | + u32 a_addr = ntohl(a->sin_addr.s_addr); |
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| 286 | + u16 a_port = ntohs(a->sin_port); |
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| 287 | + |
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| 288 | + if (addr == a_addr && port == a_port) |
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248 | 289 | return; |
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249 | | - if (xdr == a->sin6_addr.s6_addr32[3] && |
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250 | | - (u16 __force)xport < (u16 __force)a->sin6_port) |
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| 290 | + if (addr == a_addr && port < a_port) |
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251 | 291 | break; |
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252 | | - if ((u32 __force)xdr < (u32 __force)a->sin6_addr.s6_addr32[3]) |
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| 292 | + if (addr < a_addr) |
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253 | 293 | break; |
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254 | 294 | } |
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255 | 295 | |
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.. | .. |
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258 | 298 | alist->addrs + i, |
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259 | 299 | sizeof(alist->addrs[0]) * (alist->nr_addrs - i)); |
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260 | 300 | |
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261 | | - a = &alist->addrs[i].transport.sin6; |
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262 | | - a->sin6_port = xport; |
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263 | | - a->sin6_addr.s6_addr32[0] = 0; |
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264 | | - a->sin6_addr.s6_addr32[1] = 0; |
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265 | | - a->sin6_addr.s6_addr32[2] = htonl(0xffff); |
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266 | | - a->sin6_addr.s6_addr32[3] = xdr; |
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| 301 | + srx = &alist->addrs[i]; |
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| 302 | + srx->srx_family = AF_RXRPC; |
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| 303 | + srx->transport_type = SOCK_DGRAM; |
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| 304 | + srx->transport_len = sizeof(srx->transport.sin); |
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| 305 | + srx->transport.sin.sin_family = AF_INET; |
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| 306 | + srx->transport.sin.sin_port = htons(port); |
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| 307 | + srx->transport.sin.sin_addr.s_addr = xdr; |
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267 | 308 | alist->nr_ipv4++; |
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268 | 309 | alist->nr_addrs++; |
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269 | 310 | } |
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.. | .. |
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273 | 314 | */ |
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274 | 315 | void afs_merge_fs_addr6(struct afs_addr_list *alist, __be32 *xdr, u16 port) |
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275 | 316 | { |
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276 | | - struct sockaddr_in6 *a; |
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277 | | - __be16 xport = htons(port); |
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| 317 | + struct sockaddr_rxrpc *srx; |
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278 | 318 | int i, diff; |
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279 | 319 | |
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| 320 | + if (alist->nr_addrs >= alist->max_addrs) |
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| 321 | + return; |
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| 322 | + |
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280 | 323 | for (i = alist->nr_ipv4; i < alist->nr_addrs; i++) { |
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281 | | - a = &alist->addrs[i].transport.sin6; |
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| 324 | + struct sockaddr_in6 *a = &alist->addrs[i].transport.sin6; |
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| 325 | + u16 a_port = ntohs(a->sin6_port); |
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| 326 | + |
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282 | 327 | diff = memcmp(xdr, &a->sin6_addr, 16); |
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283 | | - if (diff == 0 && |
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284 | | - xport == a->sin6_port) |
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| 328 | + if (diff == 0 && port == a_port) |
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285 | 329 | return; |
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286 | | - if (diff == 0 && |
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287 | | - (u16 __force)xport < (u16 __force)a->sin6_port) |
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| 330 | + if (diff == 0 && port < a_port) |
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288 | 331 | break; |
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289 | 332 | if (diff < 0) |
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290 | 333 | break; |
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.. | .. |
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295 | 338 | alist->addrs + i, |
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296 | 339 | sizeof(alist->addrs[0]) * (alist->nr_addrs - i)); |
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297 | 340 | |
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298 | | - a = &alist->addrs[i].transport.sin6; |
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299 | | - a->sin6_port = xport; |
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300 | | - a->sin6_addr.s6_addr32[0] = xdr[0]; |
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301 | | - a->sin6_addr.s6_addr32[1] = xdr[1]; |
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302 | | - a->sin6_addr.s6_addr32[2] = xdr[2]; |
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303 | | - a->sin6_addr.s6_addr32[3] = xdr[3]; |
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| 341 | + srx = &alist->addrs[i]; |
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| 342 | + srx->srx_family = AF_RXRPC; |
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| 343 | + srx->transport_type = SOCK_DGRAM; |
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| 344 | + srx->transport_len = sizeof(srx->transport.sin6); |
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| 345 | + srx->transport.sin6.sin6_family = AF_INET6; |
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| 346 | + srx->transport.sin6.sin6_port = htons(port); |
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| 347 | + memcpy(&srx->transport.sin6.sin6_addr, xdr, 16); |
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304 | 348 | alist->nr_addrs++; |
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305 | 349 | } |
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306 | 350 | |
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.. | .. |
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309 | 353 | */ |
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310 | 354 | bool afs_iterate_addresses(struct afs_addr_cursor *ac) |
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311 | 355 | { |
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312 | | - _enter("%hu+%hd", ac->start, (short)ac->index); |
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| 356 | + unsigned long set, failed; |
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| 357 | + int index; |
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313 | 358 | |
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314 | 359 | if (!ac->alist) |
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315 | 360 | return false; |
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316 | 361 | |
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317 | | - if (ac->begun) { |
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318 | | - ac->index++; |
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319 | | - if (ac->index == ac->alist->nr_addrs) |
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320 | | - ac->index = 0; |
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| 362 | + set = ac->alist->responded; |
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| 363 | + failed = ac->alist->failed; |
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| 364 | + _enter("%lx-%lx-%lx,%d", set, failed, ac->tried, ac->index); |
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321 | 365 | |
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322 | | - if (ac->index == ac->start) { |
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323 | | - ac->error = -EDESTADDRREQ; |
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324 | | - return false; |
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325 | | - } |
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326 | | - } |
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| 366 | + ac->nr_iterations++; |
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327 | 367 | |
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328 | | - ac->begun = true; |
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| 368 | + set &= ~(failed | ac->tried); |
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| 369 | + |
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| 370 | + if (!set) |
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| 371 | + return false; |
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| 372 | + |
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| 373 | + index = READ_ONCE(ac->alist->preferred); |
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| 374 | + if (test_bit(index, &set)) |
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| 375 | + goto selected; |
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| 376 | + |
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| 377 | + index = __ffs(set); |
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| 378 | + |
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| 379 | +selected: |
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| 380 | + ac->index = index; |
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| 381 | + set_bit(index, &ac->tried); |
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329 | 382 | ac->responded = false; |
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330 | | - ac->addr = &ac->alist->addrs[ac->index]; |
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331 | 383 | return true; |
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332 | 384 | } |
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333 | 385 | |
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.. | .. |
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340 | 392 | |
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341 | 393 | alist = ac->alist; |
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342 | 394 | if (alist) { |
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343 | | - if (ac->responded && ac->index != ac->start) |
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344 | | - WRITE_ONCE(alist->index, ac->index); |
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| 395 | + if (ac->responded && |
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| 396 | + ac->index != alist->preferred && |
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| 397 | + test_bit(ac->alist->preferred, &ac->tried)) |
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| 398 | + WRITE_ONCE(alist->preferred, ac->index); |
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345 | 399 | afs_put_addrlist(alist); |
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| 400 | + ac->alist = NULL; |
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346 | 401 | } |
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347 | 402 | |
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348 | | - ac->addr = NULL; |
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349 | | - ac->alist = NULL; |
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350 | | - ac->begun = false; |
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351 | 403 | return ac->error; |
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352 | | -} |
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353 | | - |
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354 | | -/* |
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355 | | - * Set the address cursor for iterating over VL servers. |
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356 | | - */ |
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357 | | -int afs_set_vl_cursor(struct afs_addr_cursor *ac, struct afs_cell *cell) |
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358 | | -{ |
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359 | | - struct afs_addr_list *alist; |
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360 | | - int ret; |
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361 | | - |
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362 | | - if (!rcu_access_pointer(cell->vl_addrs)) { |
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363 | | - ret = wait_on_bit(&cell->flags, AFS_CELL_FL_NO_LOOKUP_YET, |
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364 | | - TASK_INTERRUPTIBLE); |
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365 | | - if (ret < 0) |
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366 | | - return ret; |
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367 | | - |
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368 | | - if (!rcu_access_pointer(cell->vl_addrs) && |
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369 | | - ktime_get_real_seconds() < cell->dns_expiry) |
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370 | | - return cell->error; |
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371 | | - } |
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372 | | - |
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373 | | - read_lock(&cell->vl_addrs_lock); |
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374 | | - alist = rcu_dereference_protected(cell->vl_addrs, |
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375 | | - lockdep_is_held(&cell->vl_addrs_lock)); |
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376 | | - if (alist->nr_addrs > 0) |
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377 | | - afs_get_addrlist(alist); |
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378 | | - else |
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379 | | - alist = NULL; |
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380 | | - read_unlock(&cell->vl_addrs_lock); |
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381 | | - |
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382 | | - if (!alist) |
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383 | | - return -EDESTADDRREQ; |
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384 | | - |
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385 | | - ac->alist = alist; |
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386 | | - ac->addr = NULL; |
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387 | | - ac->start = READ_ONCE(alist->index); |
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388 | | - ac->index = ac->start; |
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389 | | - ac->error = 0; |
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390 | | - ac->begun = false; |
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391 | | - return 0; |
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392 | 404 | } |
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