1 | /* vi: set sw=4 ts=4: */
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2 | /*
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3 | * A simple tftp client/server for busybox.
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4 | * Tries to follow RFC1350.
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5 | * Only "octet" mode supported.
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6 | * Optional blocksize negotiation (RFC2347 + RFC2348)
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7 | *
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8 | * Copyright (C) 2001 Magnus Damm <damm@opensource.se>
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9 | *
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10 | * Parts of the code based on:
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11 | *
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12 | * atftp: Copyright (C) 2000 Jean-Pierre Lefebvre <helix@step.polymtl.ca>
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13 | * and Remi Lefebvre <remi@debian.org>
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14 | *
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15 | * utftp: Copyright (C) 1999 Uwe Ohse <uwe@ohse.de>
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16 | *
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17 | * tftpd added by Denys Vlasenko & Vladimir Dronnikov
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18 | *
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19 | * Licensed under GPLv2 or later, see file LICENSE in this source tree.
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20 | */
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21 | #include "libbb.h"
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22 |
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23 | #if ENABLE_FEATURE_TFTP_GET || ENABLE_FEATURE_TFTP_PUT
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24 |
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25 | #define TFTP_BLKSIZE_DEFAULT 512 /* according to RFC 1350, don't change */
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26 | #define TFTP_BLKSIZE_DEFAULT_STR "512"
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27 | /* Was 50 ms but users asked to bump it up a bit */
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28 | #define TFTP_TIMEOUT_MS 100
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29 | #define TFTP_MAXTIMEOUT_MS 2000
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30 | #define TFTP_NUM_RETRIES 12 /* number of backed-off retries */
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31 |
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32 | /* opcodes we support */
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33 | #define TFTP_RRQ 1
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34 | #define TFTP_WRQ 2
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35 | #define TFTP_DATA 3
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36 | #define TFTP_ACK 4
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37 | #define TFTP_ERROR 5
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38 | #define TFTP_OACK 6
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39 |
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40 | /* error codes sent over network (we use only 0, 1, 3 and 8) */
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41 | /* generic (error message is included in the packet) */
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42 | #define ERR_UNSPEC 0
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43 | #define ERR_NOFILE 1
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44 | #define ERR_ACCESS 2
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45 | /* disk full or allocation exceeded */
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46 | #define ERR_WRITE 3
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47 | #define ERR_OP 4
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48 | #define ERR_BAD_ID 5
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49 | #define ERR_EXIST 6
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50 | #define ERR_BAD_USER 7
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51 | #define ERR_BAD_OPT 8
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52 |
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53 | /* masks coming from getopt32 */
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54 | enum {
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55 | TFTP_OPT_GET = (1 << 0),
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56 | TFTP_OPT_PUT = (1 << 1),
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57 | /* pseudo option: if set, it's tftpd */
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58 | TFTPD_OPT = (1 << 7) * ENABLE_TFTPD,
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59 | TFTPD_OPT_r = (1 << 8) * ENABLE_TFTPD,
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60 | TFTPD_OPT_c = (1 << 9) * ENABLE_TFTPD,
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61 | TFTPD_OPT_u = (1 << 10) * ENABLE_TFTPD,
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62 | };
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63 |
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64 | #if ENABLE_FEATURE_TFTP_GET && !ENABLE_FEATURE_TFTP_PUT
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65 | #define IF_GETPUT(...)
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66 | #define CMD_GET(cmd) 1
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67 | #define CMD_PUT(cmd) 0
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68 | #elif !ENABLE_FEATURE_TFTP_GET && ENABLE_FEATURE_TFTP_PUT
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69 | #define IF_GETPUT(...)
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70 | #define CMD_GET(cmd) 0
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71 | #define CMD_PUT(cmd) 1
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72 | #else
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73 | #define IF_GETPUT(...) __VA_ARGS__
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74 | #define CMD_GET(cmd) ((cmd) & TFTP_OPT_GET)
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75 | #define CMD_PUT(cmd) ((cmd) & TFTP_OPT_PUT)
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76 | #endif
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77 | /* NB: in the code below
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78 | * CMD_GET(cmd) and CMD_PUT(cmd) are mutually exclusive
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79 | */
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80 |
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81 |
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82 | struct globals {
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83 | /* u16 TFTP_ERROR; u16 reason; both network-endian, then error text: */
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84 | uint8_t error_pkt[4 + 32];
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85 | char *user_opt;
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86 | /* used in tftpd_main(), a bit big for stack: */
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87 | char block_buf[TFTP_BLKSIZE_DEFAULT];
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88 | #if ENABLE_FEATURE_TFTP_PROGRESS_BAR
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89 | off_t pos;
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90 | off_t size;
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91 | const char *file;
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92 | bb_progress_t pmt;
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93 | #endif
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94 | } FIX_ALIASING;
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95 | #define G (*(struct globals*)&bb_common_bufsiz1)
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96 | struct BUG_G_too_big {
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97 | char BUG_G_too_big[sizeof(G) <= COMMON_BUFSIZE ? 1 : -1];
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98 | };
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99 | #define block_buf (G.block_buf )
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100 | #define user_opt (G.user_opt )
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101 | #define error_pkt (G.error_pkt )
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102 | #define INIT_G() do { } while (0)
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103 |
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104 | #define error_pkt_reason (error_pkt[3])
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105 | #define error_pkt_str (error_pkt + 4)
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106 |
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107 | #if ENABLE_FEATURE_TFTP_PROGRESS_BAR
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108 | static void tftp_progress_update(void)
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109 | {
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110 | bb_progress_update(&G.pmt, G.file, 0, G.pos, G.size);
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111 | }
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112 | static void tftp_progress_init(void)
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113 | {
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114 | bb_progress_init(&G.pmt);
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115 | tftp_progress_update();
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116 | }
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117 | static void tftp_progress_done(void)
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118 | {
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119 | if (G.pmt.inited) {
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120 | tftp_progress_update();
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121 | bb_putchar_stderr('\n');
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122 | G.pmt.inited = 0;
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123 | }
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124 | }
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125 | #else
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126 | # define tftp_progress_init() ((void)0)
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127 | # define tftp_progress_done() ((void)0)
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128 | #endif
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129 |
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130 | #if ENABLE_FEATURE_TFTP_BLOCKSIZE
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131 |
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132 | static int tftp_blksize_check(const char *blksize_str, int maxsize)
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133 | {
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134 | /* Check if the blksize is valid:
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135 | * RFC2348 says between 8 and 65464,
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136 | * but our implementation makes it impossible
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137 | * to use blksizes smaller than 22 octets. */
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138 | unsigned blksize = bb_strtou(blksize_str, NULL, 10);
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139 | if (errno
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140 | || (blksize < 24) || (blksize > maxsize)
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141 | ) {
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142 | bb_error_msg("bad blocksize '%s'", blksize_str);
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143 | return -1;
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144 | }
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145 | # if ENABLE_TFTP_DEBUG
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146 | bb_error_msg("using blksize %u", blksize);
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147 | # endif
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148 | return blksize;
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149 | }
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150 |
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151 | static char *tftp_get_option(const char *option, char *buf, int len)
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152 | {
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153 | int opt_val = 0;
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154 | int opt_found = 0;
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155 | int k;
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156 |
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157 | /* buf points to:
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158 | * "opt_name<NUL>opt_val<NUL>opt_name2<NUL>opt_val2<NUL>..." */
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159 |
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160 | while (len > 0) {
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161 | /* Make sure options are terminated correctly */
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162 | for (k = 0; k < len; k++) {
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163 | if (buf[k] == '\0') {
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164 | goto nul_found;
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165 | }
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166 | }
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167 | return NULL;
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168 | nul_found:
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169 | if (opt_val == 0) { /* it's "name" part */
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170 | if (strcasecmp(buf, option) == 0) {
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171 | opt_found = 1;
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172 | }
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173 | } else if (opt_found) {
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174 | return buf;
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175 | }
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176 |
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177 | k++;
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178 | buf += k;
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179 | len -= k;
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180 | opt_val ^= 1;
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181 | }
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182 |
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183 | return NULL;
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184 | }
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185 |
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186 | #endif
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187 |
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188 | static int tftp_protocol(
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189 | /* NULL if tftp, !NULL if tftpd: */
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190 | len_and_sockaddr *our_lsa,
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191 | len_and_sockaddr *peer_lsa,
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192 | const char *local_file
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193 | IF_TFTP(, const char *remote_file)
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194 | #if !ENABLE_TFTP
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195 | # define remote_file NULL
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196 | #endif
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197 | /* 1 for tftp; 1/0 for tftpd depending whether client asked about it: */
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198 | IF_FEATURE_TFTP_BLOCKSIZE(, int want_transfer_size)
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199 | IF_FEATURE_TFTP_BLOCKSIZE(, int blksize))
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200 | {
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201 | #if !ENABLE_FEATURE_TFTP_BLOCKSIZE
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202 | enum { blksize = TFTP_BLKSIZE_DEFAULT };
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203 | #endif
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204 |
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205 | struct pollfd pfd[1];
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206 | #define socket_fd (pfd[0].fd)
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207 | int len;
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208 | int send_len;
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209 | IF_FEATURE_TFTP_BLOCKSIZE(smallint expect_OACK = 0;)
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210 | smallint finished = 0;
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211 | uint16_t opcode;
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212 | uint16_t block_nr;
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213 | uint16_t recv_blk;
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214 | int open_mode, local_fd;
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215 | int retries, waittime_ms;
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216 | int io_bufsize = blksize + 4;
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217 | char *cp;
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218 | /* Can't use RESERVE_CONFIG_BUFFER here since the allocation
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219 | * size varies meaning BUFFERS_GO_ON_STACK would fail.
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220 | *
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221 | * We must keep the transmit and receive buffers separate
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222 | * in case we rcv a garbage pkt - we need to rexmit the last pkt.
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223 | */
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224 | char *xbuf = xmalloc(io_bufsize);
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225 | char *rbuf = xmalloc(io_bufsize);
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226 |
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227 | socket_fd = xsocket(peer_lsa->u.sa.sa_family, SOCK_DGRAM, 0);
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228 | setsockopt_reuseaddr(socket_fd);
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229 |
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230 | if (!ENABLE_TFTP || our_lsa) { /* tftpd */
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231 | /* Create a socket which is:
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232 | * 1. bound to IP:port peer sent 1st datagram to,
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233 | * 2. connected to peer's IP:port
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234 | * This way we will answer from the IP:port peer
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235 | * expects, will not get any other packets on
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236 | * the socket, and also plain read/write will work. */
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237 | xbind(socket_fd, &our_lsa->u.sa, our_lsa->len);
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238 | xconnect(socket_fd, &peer_lsa->u.sa, peer_lsa->len);
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239 |
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240 | /* Is there an error already? Send pkt and bail out */
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241 | if (error_pkt_reason || error_pkt_str[0])
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242 | goto send_err_pkt;
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243 |
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244 | if (user_opt) {
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245 | struct passwd *pw = xgetpwnam(user_opt);
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246 | change_identity(pw); /* initgroups, setgid, setuid */
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247 | }
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248 | }
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249 |
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250 | /* Prepare open mode */
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251 | if (CMD_PUT(option_mask32)) {
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252 | open_mode = O_RDONLY;
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253 | } else {
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254 | open_mode = O_WRONLY | O_TRUNC | O_CREAT;
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255 | #if ENABLE_TFTPD
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256 | if ((option_mask32 & (TFTPD_OPT+TFTPD_OPT_c)) == TFTPD_OPT) {
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257 | /* tftpd without -c */
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258 | open_mode = O_WRONLY | O_TRUNC;
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259 | }
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260 | #endif
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261 | }
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262 |
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263 | /* Examples of network traffic.
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264 | * Note two cases when ACKs with block# of 0 are sent.
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265 | *
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266 | * Download without options:
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267 | * tftp -> "\0\1FILENAME\0octet\0"
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268 | * "\0\3\0\1FILEDATA..." <- tftpd
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269 | * tftp -> "\0\4\0\1"
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270 | * ...
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271 | * Download with option of blksize 16384:
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272 | * tftp -> "\0\1FILENAME\0octet\0blksize\00016384\0"
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273 | * "\0\6blksize\00016384\0" <- tftpd
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274 | * tftp -> "\0\4\0\0"
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275 | * "\0\3\0\1FILEDATA..." <- tftpd
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276 | * tftp -> "\0\4\0\1"
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277 | * ...
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278 | * Upload without options:
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279 | * tftp -> "\0\2FILENAME\0octet\0"
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280 | * "\0\4\0\0" <- tftpd
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281 | * tftp -> "\0\3\0\1FILEDATA..."
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282 | * "\0\4\0\1" <- tftpd
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283 | * ...
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284 | * Upload with option of blksize 16384:
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285 | * tftp -> "\0\2FILENAME\0octet\0blksize\00016384\0"
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286 | * "\0\6blksize\00016384\0" <- tftpd
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287 | * tftp -> "\0\3\0\1FILEDATA..."
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288 | * "\0\4\0\1" <- tftpd
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289 | * ...
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290 | */
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291 | block_nr = 1;
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292 | cp = xbuf + 2;
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293 |
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294 | if (!ENABLE_TFTP || our_lsa) { /* tftpd */
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295 | /* Open file (must be after changing user) */
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296 | local_fd = open(local_file, open_mode, 0666);
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297 | if (local_fd < 0) {
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298 | error_pkt_reason = ERR_NOFILE;
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299 | strcpy((char*)error_pkt_str, "can't open file");
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300 | goto send_err_pkt;
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301 | }
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302 | /* gcc 4.3.1 would NOT optimize it out as it should! */
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303 | #if ENABLE_FEATURE_TFTP_BLOCKSIZE
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304 | if (blksize != TFTP_BLKSIZE_DEFAULT || want_transfer_size) {
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305 | /* Create and send OACK packet. */
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306 | /* For the download case, block_nr is still 1 -
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307 | * we expect 1st ACK from peer to be for (block_nr-1),
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308 | * that is, for "block 0" which is our OACK pkt */
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309 | opcode = TFTP_OACK;
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310 | goto add_blksize_opt;
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311 | }
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312 | #endif
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313 | if (CMD_GET(option_mask32)) {
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314 | /* It's upload and we don't send OACK.
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315 | * We must ACK 1st packet (with filename)
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316 | * as if it is "block 0" */
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317 | block_nr = 0;
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318 | }
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319 |
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320 | } else { /* tftp */
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321 | /* Open file (must be after changing user) */
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322 | local_fd = CMD_GET(option_mask32) ? STDOUT_FILENO : STDIN_FILENO;
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323 | if (NOT_LONE_DASH(local_file))
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324 | local_fd = xopen(local_file, open_mode);
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325 | /* Removing #if, or using if() statement instead of #if may lead to
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326 | * "warning: null argument where non-null required": */
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327 | #if ENABLE_TFTP
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328 | /* tftp */
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329 |
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330 | /* We can't (and don't really need to) bind the socket:
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331 | * we don't know from which local IP datagrams will be sent,
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332 | * but kernel will pick the same IP every time (unless routing
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333 | * table is changed), thus peer will see dgrams consistently
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334 | * coming from the same IP.
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335 | * We would like to connect the socket, but since peer's
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336 | * UDP code can be less perfect than ours, _peer's_ IP:port
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337 | * in replies may differ from IP:port we used to send
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338 | * our first packet. We can connect() only when we get
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339 | * first reply. */
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340 |
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341 | /* build opcode */
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342 | opcode = TFTP_WRQ;
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343 | if (CMD_GET(option_mask32)) {
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344 | opcode = TFTP_RRQ;
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345 | }
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346 | /* add filename and mode */
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347 | /* fill in packet if the filename fits into xbuf */
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348 | len = strlen(remote_file) + 1;
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349 | if (2 + len + sizeof("octet") >= io_bufsize) {
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350 | bb_error_msg("remote filename is too long");
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351 | goto ret;
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352 | }
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353 | strcpy(cp, remote_file);
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354 | cp += len;
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355 | /* add "mode" part of the packet */
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356 | strcpy(cp, "octet");
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357 | cp += sizeof("octet");
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358 |
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359 | # if ENABLE_FEATURE_TFTP_BLOCKSIZE
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360 | if (blksize == TFTP_BLKSIZE_DEFAULT && !want_transfer_size)
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361 | goto send_pkt;
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362 |
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363 | /* Need to add option to pkt */
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364 | if ((&xbuf[io_bufsize - 1] - cp) < sizeof("blksize NNNNN tsize ") + sizeof(off_t)*3) {
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365 | bb_error_msg("remote filename is too long");
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366 | goto ret;
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367 | }
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368 | expect_OACK = 1;
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369 | # endif
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370 | #endif /* ENABLE_TFTP */
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371 |
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372 | #if ENABLE_FEATURE_TFTP_BLOCKSIZE
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373 | add_blksize_opt:
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374 | if (blksize != TFTP_BLKSIZE_DEFAULT) {
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375 | /* add "blksize", <nul>, blksize, <nul> */
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376 | strcpy(cp, "blksize");
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377 | cp += sizeof("blksize");
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378 | cp += snprintf(cp, 6, "%d", blksize) + 1;
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379 | }
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380 | if (want_transfer_size) {
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381 | /* add "tsize", <nul>, size, <nul> (see RFC2349) */
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382 | /* if tftp and downloading, we send "0" (since we opened local_fd with O_TRUNC)
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383 | * and this makes server to send "tsize" option with the size */
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384 | /* if tftp and uploading, we send file size (maybe dont, to not confuse old servers???) */
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385 | /* if tftpd and downloading, we are answering to client's request */
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386 | /* if tftpd and uploading: !want_transfer_size, this code is not executed */
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387 | struct stat st;
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388 | strcpy(cp, "tsize");
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389 | cp += sizeof("tsize");
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390 | st.st_size = 0;
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391 | fstat(local_fd, &st);
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392 | cp += sprintf(cp, "%"OFF_FMT"u", (off_t)st.st_size) + 1;
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393 | # if ENABLE_FEATURE_TFTP_PROGRESS_BAR
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394 | /* Save for progress bar. If 0 (tftp downloading),
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395 | * we look at server's reply later */
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396 | G.size = st.st_size;
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397 | if (remote_file && st.st_size)
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398 | tftp_progress_init();
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399 | # endif
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400 | }
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401 | #endif
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402 | /* First packet is built, so skip packet generation */
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403 | goto send_pkt;
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404 | }
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405 |
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406 | /* Using mostly goto's - continue/break will be less clear
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407 | * in where we actually jump to */
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408 | while (1) {
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409 | /* Build ACK or DATA */
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410 | cp = xbuf + 2;
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411 | *((uint16_t*)cp) = htons(block_nr);
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412 | cp += 2;
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413 | block_nr++;
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414 | opcode = TFTP_ACK;
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415 | if (CMD_PUT(option_mask32)) {
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416 | opcode = TFTP_DATA;
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417 | len = full_read(local_fd, cp, blksize);
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418 | if (len < 0) {
|
---|
419 | goto send_read_err_pkt;
|
---|
420 | }
|
---|
421 | if (len != blksize) {
|
---|
422 | finished = 1;
|
---|
423 | }
|
---|
424 | cp += len;
|
---|
425 | }
|
---|
426 | send_pkt:
|
---|
427 | /* Send packet */
|
---|
428 | *((uint16_t*)xbuf) = htons(opcode); /* fill in opcode part */
|
---|
429 | send_len = cp - xbuf;
|
---|
430 | /* NB: send_len value is preserved in code below
|
---|
431 | * for potential resend */
|
---|
432 |
|
---|
433 | retries = TFTP_NUM_RETRIES; /* re-initialize */
|
---|
434 | waittime_ms = TFTP_TIMEOUT_MS;
|
---|
435 |
|
---|
436 | send_again:
|
---|
437 | #if ENABLE_TFTP_DEBUG
|
---|
438 | fprintf(stderr, "sending %u bytes\n", send_len);
|
---|
439 | for (cp = xbuf; cp < &xbuf[send_len]; cp++)
|
---|
440 | fprintf(stderr, "%02x ", (unsigned char) *cp);
|
---|
441 | fprintf(stderr, "\n");
|
---|
442 | #endif
|
---|
443 | xsendto(socket_fd, xbuf, send_len, &peer_lsa->u.sa, peer_lsa->len);
|
---|
444 |
|
---|
445 | #if ENABLE_FEATURE_TFTP_PROGRESS_BAR
|
---|
446 | if (ENABLE_TFTP && remote_file) /* tftp */
|
---|
447 | G.pos = (block_nr - 1) * (uoff_t)blksize;
|
---|
448 | if (G.pmt.inited)
|
---|
449 | tftp_progress_update();
|
---|
450 | #endif
|
---|
451 | /* Was it final ACK? then exit */
|
---|
452 | if (finished && (opcode == TFTP_ACK))
|
---|
453 | goto ret;
|
---|
454 |
|
---|
455 | recv_again:
|
---|
456 | /* Receive packet */
|
---|
457 | /*pfd[0].fd = socket_fd;*/
|
---|
458 | pfd[0].events = POLLIN;
|
---|
459 | switch (safe_poll(pfd, 1, waittime_ms)) {
|
---|
460 | default:
|
---|
461 | /*bb_perror_msg("poll"); - done in safe_poll */
|
---|
462 | goto ret;
|
---|
463 | case 0:
|
---|
464 | retries--;
|
---|
465 | if (retries == 0) {
|
---|
466 | tftp_progress_done();
|
---|
467 | bb_error_msg("timeout");
|
---|
468 | goto ret; /* no err packet sent */
|
---|
469 | }
|
---|
470 |
|
---|
471 | /* exponential backoff with limit */
|
---|
472 | waittime_ms += waittime_ms/2;
|
---|
473 | if (waittime_ms > TFTP_MAXTIMEOUT_MS) {
|
---|
474 | waittime_ms = TFTP_MAXTIMEOUT_MS;
|
---|
475 | }
|
---|
476 |
|
---|
477 | goto send_again; /* resend last sent pkt */
|
---|
478 | case 1:
|
---|
479 | if (!our_lsa) {
|
---|
480 | /* tftp (not tftpd!) receiving 1st packet */
|
---|
481 | our_lsa = ((void*)(ptrdiff_t)-1); /* not NULL */
|
---|
482 | len = recvfrom(socket_fd, rbuf, io_bufsize, 0,
|
---|
483 | &peer_lsa->u.sa, &peer_lsa->len);
|
---|
484 | /* Our first dgram went to port 69
|
---|
485 | * but reply may come from different one.
|
---|
486 | * Remember and use this new port (and IP) */
|
---|
487 | if (len >= 0)
|
---|
488 | xconnect(socket_fd, &peer_lsa->u.sa, peer_lsa->len);
|
---|
489 | } else {
|
---|
490 | /* tftpd, or not the very first packet:
|
---|
491 | * socket is connect()ed, can just read from it. */
|
---|
492 | /* Don't full_read()!
|
---|
493 | * This is not TCP, one read == one pkt! */
|
---|
494 | len = safe_read(socket_fd, rbuf, io_bufsize);
|
---|
495 | }
|
---|
496 | if (len < 0) {
|
---|
497 | goto send_read_err_pkt;
|
---|
498 | }
|
---|
499 | if (len < 4) { /* too small? */
|
---|
500 | goto recv_again;
|
---|
501 | }
|
---|
502 | }
|
---|
503 |
|
---|
504 | /* Process recv'ed packet */
|
---|
505 | opcode = ntohs( ((uint16_t*)rbuf)[0] );
|
---|
506 | recv_blk = ntohs( ((uint16_t*)rbuf)[1] );
|
---|
507 | #if ENABLE_TFTP_DEBUG
|
---|
508 | fprintf(stderr, "received %d bytes: %04x %04x\n", len, opcode, recv_blk);
|
---|
509 | #endif
|
---|
510 | if (opcode == TFTP_ERROR) {
|
---|
511 | static const char errcode_str[] ALIGN1 =
|
---|
512 | "\0"
|
---|
513 | "file not found\0"
|
---|
514 | "access violation\0"
|
---|
515 | "disk full\0"
|
---|
516 | "bad operation\0"
|
---|
517 | "unknown transfer id\0"
|
---|
518 | "file already exists\0"
|
---|
519 | "no such user\0"
|
---|
520 | "bad option";
|
---|
521 |
|
---|
522 | const char *msg = "";
|
---|
523 |
|
---|
524 | if (len > 4 && rbuf[4] != '\0') {
|
---|
525 | msg = &rbuf[4];
|
---|
526 | rbuf[io_bufsize - 1] = '\0'; /* paranoia */
|
---|
527 | } else if (recv_blk <= 8) {
|
---|
528 | msg = nth_string(errcode_str, recv_blk);
|
---|
529 | }
|
---|
530 | bb_error_msg("server error: (%u) %s", recv_blk, msg);
|
---|
531 | goto ret;
|
---|
532 | }
|
---|
533 |
|
---|
534 | #if ENABLE_FEATURE_TFTP_BLOCKSIZE
|
---|
535 | if (expect_OACK) {
|
---|
536 | expect_OACK = 0;
|
---|
537 | if (opcode == TFTP_OACK) {
|
---|
538 | /* server seems to support options */
|
---|
539 | char *res;
|
---|
540 |
|
---|
541 | res = tftp_get_option("blksize", &rbuf[2], len - 2);
|
---|
542 | if (res) {
|
---|
543 | blksize = tftp_blksize_check(res, blksize);
|
---|
544 | if (blksize < 0) {
|
---|
545 | error_pkt_reason = ERR_BAD_OPT;
|
---|
546 | goto send_err_pkt;
|
---|
547 | }
|
---|
548 | io_bufsize = blksize + 4;
|
---|
549 | }
|
---|
550 | # if ENABLE_FEATURE_TFTP_PROGRESS_BAR
|
---|
551 | if (remote_file && G.size == 0) { /* if we don't know it yet */
|
---|
552 | res = tftp_get_option("tsize", &rbuf[2], len - 2);
|
---|
553 | if (res) {
|
---|
554 | G.size = bb_strtoull(res, NULL, 10);
|
---|
555 | if (G.size)
|
---|
556 | tftp_progress_init();
|
---|
557 | }
|
---|
558 | }
|
---|
559 | # endif
|
---|
560 | if (CMD_GET(option_mask32)) {
|
---|
561 | /* We'll send ACK for OACK,
|
---|
562 | * such ACK has "block no" of 0 */
|
---|
563 | block_nr = 0;
|
---|
564 | }
|
---|
565 | continue;
|
---|
566 | }
|
---|
567 | /* rfc2347:
|
---|
568 | * "An option not acknowledged by the server
|
---|
569 | * must be ignored by the client and server
|
---|
570 | * as if it were never requested." */
|
---|
571 | if (blksize != TFTP_BLKSIZE_DEFAULT)
|
---|
572 | bb_error_msg("falling back to blocksize "TFTP_BLKSIZE_DEFAULT_STR);
|
---|
573 | blksize = TFTP_BLKSIZE_DEFAULT;
|
---|
574 | io_bufsize = TFTP_BLKSIZE_DEFAULT + 4;
|
---|
575 | }
|
---|
576 | #endif
|
---|
577 | /* block_nr is already advanced to next block# we expect
|
---|
578 | * to get / block# we are about to send next time */
|
---|
579 |
|
---|
580 | if (CMD_GET(option_mask32) && (opcode == TFTP_DATA)) {
|
---|
581 | if (recv_blk == block_nr) {
|
---|
582 | int sz = full_write(local_fd, &rbuf[4], len - 4);
|
---|
583 | if (sz != len - 4) {
|
---|
584 | strcpy((char*)error_pkt_str, bb_msg_write_error);
|
---|
585 | error_pkt_reason = ERR_WRITE;
|
---|
586 | goto send_err_pkt;
|
---|
587 | }
|
---|
588 | if (sz != blksize) {
|
---|
589 | finished = 1;
|
---|
590 | }
|
---|
591 | continue; /* send ACK */
|
---|
592 | }
|
---|
593 | /* Disabled to cope with servers with Sorcerer's Apprentice Syndrome */
|
---|
594 | #if 0
|
---|
595 | if (recv_blk == (block_nr - 1)) {
|
---|
596 | /* Server lost our TFTP_ACK. Resend it */
|
---|
597 | block_nr = recv_blk;
|
---|
598 | continue;
|
---|
599 | }
|
---|
600 | #endif
|
---|
601 | }
|
---|
602 |
|
---|
603 | if (CMD_PUT(option_mask32) && (opcode == TFTP_ACK)) {
|
---|
604 | /* did peer ACK our last DATA pkt? */
|
---|
605 | if (recv_blk == (uint16_t) (block_nr - 1)) {
|
---|
606 | if (finished)
|
---|
607 | goto ret;
|
---|
608 | continue; /* send next block */
|
---|
609 | }
|
---|
610 | }
|
---|
611 | /* Awww... recv'd packet is not recognized! */
|
---|
612 | goto recv_again;
|
---|
613 | /* why recv_again? - rfc1123 says:
|
---|
614 | * "The sender (i.e., the side originating the DATA packets)
|
---|
615 | * must never resend the current DATA packet on receipt
|
---|
616 | * of a duplicate ACK".
|
---|
617 | * DATA pkts are resent ONLY on timeout.
|
---|
618 | * Thus "goto send_again" will ba a bad mistake above.
|
---|
619 | * See:
|
---|
620 | * http://en.wikipedia.org/wiki/Sorcerer's_Apprentice_Syndrome
|
---|
621 | */
|
---|
622 | } /* end of "while (1)" */
|
---|
623 | ret:
|
---|
624 | if (ENABLE_FEATURE_CLEAN_UP) {
|
---|
625 | close(local_fd);
|
---|
626 | close(socket_fd);
|
---|
627 | free(xbuf);
|
---|
628 | free(rbuf);
|
---|
629 | }
|
---|
630 | return finished == 0; /* returns 1 on failure */
|
---|
631 |
|
---|
632 | send_read_err_pkt:
|
---|
633 | strcpy((char*)error_pkt_str, bb_msg_read_error);
|
---|
634 | send_err_pkt:
|
---|
635 | if (error_pkt_str[0])
|
---|
636 | bb_error_msg("%s", (char*)error_pkt_str);
|
---|
637 | error_pkt[1] = TFTP_ERROR;
|
---|
638 | xsendto(socket_fd, error_pkt, 4 + 1 + strlen((char*)error_pkt_str),
|
---|
639 | &peer_lsa->u.sa, peer_lsa->len);
|
---|
640 | return EXIT_FAILURE;
|
---|
641 | #undef remote_file
|
---|
642 | }
|
---|
643 |
|
---|
644 | #if ENABLE_TFTP
|
---|
645 |
|
---|
646 | int tftp_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
|
---|
647 | int tftp_main(int argc UNUSED_PARAM, char **argv)
|
---|
648 | {
|
---|
649 | len_and_sockaddr *peer_lsa;
|
---|
650 | const char *local_file = NULL;
|
---|
651 | const char *remote_file = NULL;
|
---|
652 | # if ENABLE_FEATURE_TFTP_BLOCKSIZE
|
---|
653 | const char *blksize_str = TFTP_BLKSIZE_DEFAULT_STR;
|
---|
654 | int blksize;
|
---|
655 | # endif
|
---|
656 | int result;
|
---|
657 | int port;
|
---|
658 | IF_GETPUT(int opt;)
|
---|
659 |
|
---|
660 | INIT_G();
|
---|
661 |
|
---|
662 | /* -p or -g is mandatory, and they are mutually exclusive */
|
---|
663 | opt_complementary = "" IF_FEATURE_TFTP_GET("g:") IF_FEATURE_TFTP_PUT("p:")
|
---|
664 | IF_GETPUT("g--p:p--g:");
|
---|
665 |
|
---|
666 | IF_GETPUT(opt =) getopt32(argv,
|
---|
667 | IF_FEATURE_TFTP_GET("g") IF_FEATURE_TFTP_PUT("p")
|
---|
668 | "l:r:" IF_FEATURE_TFTP_BLOCKSIZE("b:"),
|
---|
669 | &local_file, &remote_file
|
---|
670 | IF_FEATURE_TFTP_BLOCKSIZE(, &blksize_str));
|
---|
671 | argv += optind;
|
---|
672 |
|
---|
673 | # if ENABLE_FEATURE_TFTP_BLOCKSIZE
|
---|
674 | /* Check if the blksize is valid:
|
---|
675 | * RFC2348 says between 8 and 65464 */
|
---|
676 | blksize = tftp_blksize_check(blksize_str, 65564);
|
---|
677 | if (blksize < 0) {
|
---|
678 | //bb_error_msg("bad block size");
|
---|
679 | return EXIT_FAILURE;
|
---|
680 | }
|
---|
681 | # endif
|
---|
682 |
|
---|
683 | if (remote_file) {
|
---|
684 | if (!local_file) {
|
---|
685 | const char *slash = strrchr(remote_file, '/');
|
---|
686 | local_file = slash ? slash + 1 : remote_file;
|
---|
687 | }
|
---|
688 | } else {
|
---|
689 | remote_file = local_file;
|
---|
690 | }
|
---|
691 |
|
---|
692 | /* Error if filename or host is not known */
|
---|
693 | if (!remote_file || !argv[0])
|
---|
694 | bb_show_usage();
|
---|
695 |
|
---|
696 | port = bb_lookup_port(argv[1], "udp", 69);
|
---|
697 | peer_lsa = xhost2sockaddr(argv[0], port);
|
---|
698 |
|
---|
699 | # if ENABLE_TFTP_DEBUG
|
---|
700 | fprintf(stderr, "using server '%s', remote_file '%s', local_file '%s'\n",
|
---|
701 | xmalloc_sockaddr2dotted(&peer_lsa->u.sa),
|
---|
702 | remote_file, local_file);
|
---|
703 | # endif
|
---|
704 |
|
---|
705 | # if ENABLE_FEATURE_TFTP_PROGRESS_BAR
|
---|
706 | G.file = remote_file;
|
---|
707 | # endif
|
---|
708 | result = tftp_protocol(
|
---|
709 | NULL /*our_lsa*/, peer_lsa,
|
---|
710 | local_file, remote_file
|
---|
711 | IF_FEATURE_TFTP_BLOCKSIZE(, 1 /* want_transfer_size */)
|
---|
712 | IF_FEATURE_TFTP_BLOCKSIZE(, blksize)
|
---|
713 | );
|
---|
714 | tftp_progress_done();
|
---|
715 |
|
---|
716 | if (result != EXIT_SUCCESS && NOT_LONE_DASH(local_file) && CMD_GET(opt)) {
|
---|
717 | unlink(local_file);
|
---|
718 | }
|
---|
719 | return result;
|
---|
720 | }
|
---|
721 |
|
---|
722 | #endif /* ENABLE_TFTP */
|
---|
723 |
|
---|
724 | #if ENABLE_TFTPD
|
---|
725 | int tftpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
|
---|
726 | int tftpd_main(int argc UNUSED_PARAM, char **argv)
|
---|
727 | {
|
---|
728 | len_and_sockaddr *our_lsa;
|
---|
729 | len_and_sockaddr *peer_lsa;
|
---|
730 | char *local_file, *mode;
|
---|
731 | const char *error_msg;
|
---|
732 | int opt, result, opcode;
|
---|
733 | IF_FEATURE_TFTP_BLOCKSIZE(int blksize = TFTP_BLKSIZE_DEFAULT;)
|
---|
734 | IF_FEATURE_TFTP_BLOCKSIZE(int want_transfer_size = 0;)
|
---|
735 |
|
---|
736 | INIT_G();
|
---|
737 |
|
---|
738 | our_lsa = get_sock_lsa(STDIN_FILENO);
|
---|
739 | if (!our_lsa) {
|
---|
740 | /* This is confusing:
|
---|
741 | *bb_error_msg_and_die("stdin is not a socket");
|
---|
742 | * Better: */
|
---|
743 | bb_show_usage();
|
---|
744 | /* Help text says that tftpd must be used as inetd service,
|
---|
745 | * which is by far the most usual cause of get_sock_lsa
|
---|
746 | * failure */
|
---|
747 | }
|
---|
748 | peer_lsa = xzalloc(LSA_LEN_SIZE + our_lsa->len);
|
---|
749 | peer_lsa->len = our_lsa->len;
|
---|
750 |
|
---|
751 | /* Shifting to not collide with TFTP_OPTs */
|
---|
752 | opt = option_mask32 = TFTPD_OPT | (getopt32(argv, "rcu:", &user_opt) << 8);
|
---|
753 | argv += optind;
|
---|
754 | if (argv[0])
|
---|
755 | xchdir(argv[0]);
|
---|
756 |
|
---|
757 | result = recv_from_to(STDIN_FILENO, block_buf, sizeof(block_buf),
|
---|
758 | 0 /* flags */,
|
---|
759 | &peer_lsa->u.sa, &our_lsa->u.sa, our_lsa->len);
|
---|
760 |
|
---|
761 | error_msg = "malformed packet";
|
---|
762 | opcode = ntohs(*(uint16_t*)block_buf);
|
---|
763 | if (result < 4 || result >= sizeof(block_buf)
|
---|
764 | || block_buf[result-1] != '\0'
|
---|
765 | || (IF_FEATURE_TFTP_PUT(opcode != TFTP_RRQ) /* not download */
|
---|
766 | IF_GETPUT(&&)
|
---|
767 | IF_FEATURE_TFTP_GET(opcode != TFTP_WRQ) /* not upload */
|
---|
768 | )
|
---|
769 | ) {
|
---|
770 | goto err;
|
---|
771 | }
|
---|
772 | local_file = block_buf + 2;
|
---|
773 | if (local_file[0] == '.' || strstr(local_file, "/.")) {
|
---|
774 | error_msg = "dot in file name";
|
---|
775 | goto err;
|
---|
776 | }
|
---|
777 | mode = local_file + strlen(local_file) + 1;
|
---|
778 | if (mode >= block_buf + result || strcmp(mode, "octet") != 0) {
|
---|
779 | goto err;
|
---|
780 | }
|
---|
781 | # if ENABLE_FEATURE_TFTP_BLOCKSIZE
|
---|
782 | {
|
---|
783 | char *res;
|
---|
784 | char *opt_str = mode + sizeof("octet");
|
---|
785 | int opt_len = block_buf + result - opt_str;
|
---|
786 | if (opt_len > 0) {
|
---|
787 | res = tftp_get_option("blksize", opt_str, opt_len);
|
---|
788 | if (res) {
|
---|
789 | blksize = tftp_blksize_check(res, 65564);
|
---|
790 | if (blksize < 0) {
|
---|
791 | error_pkt_reason = ERR_BAD_OPT;
|
---|
792 | /* will just send error pkt */
|
---|
793 | goto do_proto;
|
---|
794 | }
|
---|
795 | }
|
---|
796 | if (opcode != TFTP_WRQ /* download? */
|
---|
797 | /* did client ask us about file size? */
|
---|
798 | && tftp_get_option("tsize", opt_str, opt_len)
|
---|
799 | ) {
|
---|
800 | want_transfer_size = 1;
|
---|
801 | }
|
---|
802 | }
|
---|
803 | }
|
---|
804 | # endif
|
---|
805 |
|
---|
806 | if (!ENABLE_FEATURE_TFTP_PUT || opcode == TFTP_WRQ) {
|
---|
807 | if (opt & TFTPD_OPT_r) {
|
---|
808 | /* This would mean "disk full" - not true */
|
---|
809 | /*error_pkt_reason = ERR_WRITE;*/
|
---|
810 | error_msg = bb_msg_write_error;
|
---|
811 | goto err;
|
---|
812 | }
|
---|
813 | IF_GETPUT(option_mask32 |= TFTP_OPT_GET;) /* will receive file's data */
|
---|
814 | } else {
|
---|
815 | IF_GETPUT(option_mask32 |= TFTP_OPT_PUT;) /* will send file's data */
|
---|
816 | }
|
---|
817 |
|
---|
818 | /* NB: if error_pkt_str or error_pkt_reason is set up,
|
---|
819 | * tftp_protocol() just sends one error pkt and returns */
|
---|
820 |
|
---|
821 | do_proto:
|
---|
822 | close(STDIN_FILENO); /* close old, possibly wildcard socket */
|
---|
823 | /* tftp_protocol() will create new one, bound to particular local IP */
|
---|
824 | result = tftp_protocol(
|
---|
825 | our_lsa, peer_lsa,
|
---|
826 | local_file IF_TFTP(, NULL /*remote_file*/)
|
---|
827 | IF_FEATURE_TFTP_BLOCKSIZE(, want_transfer_size)
|
---|
828 | IF_FEATURE_TFTP_BLOCKSIZE(, blksize)
|
---|
829 | );
|
---|
830 |
|
---|
831 | return result;
|
---|
832 | err:
|
---|
833 | strcpy((char*)error_pkt_str, error_msg);
|
---|
834 | goto do_proto;
|
---|
835 | }
|
---|
836 |
|
---|
837 | #endif /* ENABLE_TFTPD */
|
---|
838 |
|
---|
839 | #endif /* ENABLE_FEATURE_TFTP_GET || ENABLE_FEATURE_TFTP_PUT */
|
---|