1 /* 2 * util/proxy_protocol.h - PROXY protocol 3 * 4 * Copyright (c) 2022, NLnet Labs. All rights reserved. 5 * 6 * This software is open source. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * Neither the name of the NLNET LABS nor the names of its contributors may 20 * be used to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * 39 * This file contains PROXY protocol structs and functions. 40 * Only v2 is supported. TLVs are not currently supported. 41 */ 42 #ifndef PROXY_PROTOCOL_H 43 #define PROXY_PROTOCOL_H 44 45 #include "config.h" 46 47 /** PROXYv2 minimum header size */ 48 #define PP2_HEADER_SIZE 16 49 50 /** PROXYv2 header signature */ 51 #define PP2_SIG "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A" 52 #define PP2_SIG_LEN 12 53 54 /** PROXYv2 version (protocol value) */ 55 #define PP2_VERSION 0x2 56 57 /** PROXYv2 minimum header.len value for TCP/UDP over IPv4 */ 58 #define PP2_HEADER_LEN_INET 12 59 60 /** PROXYv2 minimum header.len value for TCP/UDP over IPv6 */ 61 #define PP2_HEADER_LEN_INET6 36 62 63 /** PROXYv2 minimum header.len value for TCP/UDP over AF_UNIX */ 64 #define PP2_HEADER_LEN_UNIX 216 65 66 /** 67 * PROXYv2 command (protocol value). 68 */ 69 enum pp2_command { 70 PP2_CMD_LOCAL = 0x0, 71 PP2_CMD_PROXY = 0x1 72 }; 73 74 /** 75 * PROXYv2 address family (protocol value). 76 */ 77 enum pp2_af { 78 PP2_AF_UNSPEC = 0x0, 79 PP2_AF_INET = 0x1, 80 PP2_AF_INET6 = 0x2, 81 PP2_AF_UNIX = 0x3 82 }; 83 84 /** 85 * PROXYv2 protocol (protocol value). 86 */ 87 enum pp2_protocol { 88 PP2_PROT_UNSPEC = 0x0, 89 PP2_PROT_STREAM = 0x1, 90 PP2_PROT_DGRAM = 0x2 91 }; 92 93 /** 94 * Expected combinations of address family and protocol values used in checks. 95 */ 96 enum pp2_af_protocol_combination { 97 PP2_UNSPEC_UNSPEC = (PP2_AF_UNSPEC<<4)|PP2_PROT_UNSPEC, 98 PP2_INET_STREAM = (PP2_AF_INET<<4)|PP2_PROT_STREAM, 99 PP2_INET_DGRAM = (PP2_AF_INET<<4)|PP2_PROT_DGRAM, 100 PP2_INET6_STREAM = (PP2_AF_INET6<<4)|PP2_PROT_STREAM, 101 PP2_INET6_DGRAM = (PP2_AF_INET6<<4)|PP2_PROT_DGRAM, 102 PP2_UNIX_STREAM = (PP2_AF_UNIX<<4)|PP2_PROT_STREAM, 103 PP2_UNIX_DGRAM = (PP2_AF_UNIX<<4)|PP2_PROT_DGRAM 104 }; 105 106 /** 107 * PROXYv2 header. 108 */ 109 struct pp2_header { 110 uint8_t sig[PP2_SIG_LEN]; 111 uint8_t ver_cmd; 112 uint8_t fam_prot; 113 uint16_t len; 114 union { 115 struct { /* for TCP/UDP over IPv4, len = 12 */ 116 uint32_t src_addr; 117 uint32_t dst_addr; 118 uint16_t src_port; 119 uint16_t dst_port; 120 } addr4; 121 struct { /* for TCP/UDP over IPv6, len = 36 */ 122 uint8_t src_addr[16]; 123 uint8_t dst_addr[16]; 124 uint16_t src_port; 125 uint16_t dst_port; 126 } addr6; 127 struct { /* for AF_UNIX sockets, len = 216 */ 128 uint8_t src_addr[108]; 129 uint8_t dst_addr[108]; 130 } addru; 131 } addr; 132 }; 133 134 /** 135 * PROXY parse errors. 136 */ 137 enum pp_parse_errors { 138 PP_PARSE_NOERROR = 0, 139 PP_PARSE_SIZE, 140 PP_PARSE_WRONG_HEADERv2, 141 PP_PARSE_UNKNOWN_CMD, 142 PP_PARSE_UNKNOWN_FAM_PROT, 143 }; 144 145 /** 146 * Initialize the internal proxy structure. 147 * @param write_uint16: pointer to a function that can write uint16. 148 * @param write_uint32: pointer to a function that can write uint32. 149 */ 150 void pp_init(void (*write_uint16)(void* buf, uint16_t data), 151 void (*write_uint32)(void* buf, uint32_t data)); 152 153 /** 154 * Lookup the parsing error description. 155 * @param error: parsing error from pp2_read_header. 156 * @return the description. 157 */ 158 const char* pp_lookup_error(enum pp_parse_errors error); 159 160 /** 161 * Write a PROXYv2 header at the current position of the buffer. 162 * @param buf: pointer to the buffer to write data to. 163 * @param buflen: available size on the buffer. 164 * @param src: the source address. 165 * @param stream: if the protocol is stream or datagram. 166 * @return 1 on success, 0 on failure. 167 */ 168 size_t pp2_write_to_buf(uint8_t* buf, size_t buflen, 169 #ifdef INET6 170 struct sockaddr_storage* src, 171 #else 172 struct sockaddr_in* src, 173 #endif 174 int stream); 175 176 /** 177 * Read a PROXYv2 header from the current position of the buffer. 178 * It does initial validation and returns a pointer to the buffer position on 179 * success. 180 * @param buf: pointer to the buffer data to read from. 181 * @param buflen: available size on the buffer. 182 * @return parsing error, 0 on success. 183 */ 184 int pp2_read_header(uint8_t* buf, size_t buflen); 185 186 #endif /* PROXY_PROTOCOL_H */ 187
Indexes created Sat Oct 03 00:25:10 UTC 2026