[331] | 1 | /*
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| 2 | * Copyright 2005-2016 The OpenSSL Project Authors. All Rights Reserved.
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| 3 | *
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| 4 | * Licensed under the OpenSSL license (the "License"). You may not use
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| 5 | * this file except in compliance with the License. You can obtain a copy
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| 6 | * in the file LICENSE in the source distribution or at
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| 7 | * https://www.openssl.org/source/license.html
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| 8 | */
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| 9 |
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| 10 | #include <stdio.h>
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| 11 | #define USE_SOCKETS
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| 12 | #include <openssl/objects.h>
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| 13 | #include <openssl/rand.h>
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| 14 | #include "ssl_locl.h"
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| 15 |
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| 16 | #if defined(OPENSSL_SYS_VMS)
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| 17 | # include <sys/timeb.h>
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| 18 | #elif defined(OPENSSL_SYS_VXWORKS)
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| 19 | # include <sys/times.h>
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| 20 | #elif !defined(OPENSSL_SYS_WIN32)
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| 21 | # include <sys/time.h>
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| 22 | #endif
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| 23 |
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| 24 | static void get_current_time(struct timeval *t);
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| 25 | static int dtls1_set_handshake_header(SSL *s, int type, unsigned long len);
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| 26 | static int dtls1_handshake_write(SSL *s);
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| 27 | static unsigned int dtls1_link_min_mtu(void);
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| 28 |
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| 29 | /* XDTLS: figure out the right values */
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| 30 | static const unsigned int g_probable_mtu[] = { 1500, 512, 256 };
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| 31 |
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| 32 | const SSL3_ENC_METHOD DTLSv1_enc_data = {
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| 33 | tls1_enc,
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| 34 | tls1_mac,
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| 35 | tls1_setup_key_block,
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| 36 | tls1_generate_master_secret,
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| 37 | tls1_change_cipher_state,
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| 38 | tls1_final_finish_mac,
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| 39 | TLS1_FINISH_MAC_LENGTH,
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| 40 | TLS_MD_CLIENT_FINISH_CONST, TLS_MD_CLIENT_FINISH_CONST_SIZE,
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| 41 | TLS_MD_SERVER_FINISH_CONST, TLS_MD_SERVER_FINISH_CONST_SIZE,
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| 42 | tls1_alert_code,
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| 43 | tls1_export_keying_material,
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| 44 | SSL_ENC_FLAG_DTLS | SSL_ENC_FLAG_EXPLICIT_IV,
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| 45 | DTLS1_HM_HEADER_LENGTH,
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| 46 | dtls1_set_handshake_header,
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| 47 | dtls1_handshake_write
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| 48 | };
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| 49 |
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| 50 | const SSL3_ENC_METHOD DTLSv1_2_enc_data = {
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| 51 | tls1_enc,
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| 52 | tls1_mac,
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| 53 | tls1_setup_key_block,
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| 54 | tls1_generate_master_secret,
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| 55 | tls1_change_cipher_state,
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| 56 | tls1_final_finish_mac,
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| 57 | TLS1_FINISH_MAC_LENGTH,
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| 58 | TLS_MD_CLIENT_FINISH_CONST, TLS_MD_CLIENT_FINISH_CONST_SIZE,
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| 59 | TLS_MD_SERVER_FINISH_CONST, TLS_MD_SERVER_FINISH_CONST_SIZE,
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| 60 | tls1_alert_code,
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| 61 | tls1_export_keying_material,
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| 62 | SSL_ENC_FLAG_DTLS | SSL_ENC_FLAG_EXPLICIT_IV | SSL_ENC_FLAG_SIGALGS
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| 63 | | SSL_ENC_FLAG_SHA256_PRF | SSL_ENC_FLAG_TLS1_2_CIPHERS,
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| 64 | DTLS1_HM_HEADER_LENGTH,
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| 65 | dtls1_set_handshake_header,
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| 66 | dtls1_handshake_write
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| 67 | };
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| 68 |
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| 69 | long dtls1_default_timeout(void)
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| 70 | {
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| 71 | /*
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| 72 | * 2 hours, the 24 hours mentioned in the DTLSv1 spec is way too long for
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| 73 | * http, the cache would over fill
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| 74 | */
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| 75 | return (60 * 60 * 2);
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| 76 | }
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| 77 |
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| 78 | int dtls1_new(SSL *s)
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| 79 | {
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| 80 | DTLS1_STATE *d1;
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| 81 |
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| 82 | if (!DTLS_RECORD_LAYER_new(&s->rlayer)) {
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| 83 | return 0;
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| 84 | }
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| 85 |
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| 86 | if (!ssl3_new(s))
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| 87 | return (0);
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| 88 | if ((d1 = OPENSSL_zalloc(sizeof(*d1))) == NULL) {
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| 89 | ssl3_free(s);
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| 90 | return (0);
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| 91 | }
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| 92 |
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| 93 | d1->buffered_messages = pqueue_new();
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| 94 | d1->sent_messages = pqueue_new();
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| 95 |
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| 96 | if (s->server) {
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| 97 | d1->cookie_len = sizeof(s->d1->cookie);
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| 98 | }
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| 99 |
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| 100 | d1->link_mtu = 0;
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| 101 | d1->mtu = 0;
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| 102 |
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| 103 | if (d1->buffered_messages == NULL || d1->sent_messages == NULL) {
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| 104 | pqueue_free(d1->buffered_messages);
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| 105 | pqueue_free(d1->sent_messages);
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| 106 | OPENSSL_free(d1);
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| 107 | ssl3_free(s);
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| 108 | return (0);
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| 109 | }
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| 110 |
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| 111 | s->d1 = d1;
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| 112 | s->method->ssl_clear(s);
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| 113 | return (1);
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| 114 | }
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| 115 |
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| 116 | static void dtls1_clear_queues(SSL *s)
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| 117 | {
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| 118 | dtls1_clear_received_buffer(s);
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| 119 | dtls1_clear_sent_buffer(s);
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| 120 | }
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| 121 |
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| 122 | void dtls1_clear_received_buffer(SSL *s)
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| 123 | {
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| 124 | pitem *item = NULL;
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| 125 | hm_fragment *frag = NULL;
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| 126 |
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| 127 | while ((item = pqueue_pop(s->d1->buffered_messages)) != NULL) {
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| 128 | frag = (hm_fragment *)item->data;
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| 129 | dtls1_hm_fragment_free(frag);
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| 130 | pitem_free(item);
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| 131 | }
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| 132 | }
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| 133 |
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| 134 | void dtls1_clear_sent_buffer(SSL *s)
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| 135 | {
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| 136 | pitem *item = NULL;
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| 137 | hm_fragment *frag = NULL;
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| 138 |
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| 139 | while ((item = pqueue_pop(s->d1->sent_messages)) != NULL) {
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| 140 | frag = (hm_fragment *)item->data;
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| 141 | dtls1_hm_fragment_free(frag);
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| 142 | pitem_free(item);
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| 143 | }
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| 144 | }
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| 145 |
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| 146 |
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| 147 | void dtls1_free(SSL *s)
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| 148 | {
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| 149 | DTLS_RECORD_LAYER_free(&s->rlayer);
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| 150 |
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| 151 | ssl3_free(s);
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| 152 |
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| 153 | dtls1_clear_queues(s);
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| 154 |
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| 155 | pqueue_free(s->d1->buffered_messages);
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| 156 | pqueue_free(s->d1->sent_messages);
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| 157 |
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| 158 | OPENSSL_free(s->d1);
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| 159 | s->d1 = NULL;
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| 160 | }
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| 161 |
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| 162 | void dtls1_clear(SSL *s)
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| 163 | {
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| 164 | pqueue *buffered_messages;
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| 165 | pqueue *sent_messages;
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| 166 | unsigned int mtu;
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| 167 | unsigned int link_mtu;
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| 168 |
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| 169 | DTLS_RECORD_LAYER_clear(&s->rlayer);
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| 170 |
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| 171 | if (s->d1) {
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| 172 | buffered_messages = s->d1->buffered_messages;
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| 173 | sent_messages = s->d1->sent_messages;
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| 174 | mtu = s->d1->mtu;
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| 175 | link_mtu = s->d1->link_mtu;
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| 176 |
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| 177 | dtls1_clear_queues(s);
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| 178 |
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| 179 | memset(s->d1, 0, sizeof(*s->d1));
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| 180 |
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| 181 | if (s->server) {
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| 182 | s->d1->cookie_len = sizeof(s->d1->cookie);
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| 183 | }
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| 184 |
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| 185 | if (SSL_get_options(s) & SSL_OP_NO_QUERY_MTU) {
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| 186 | s->d1->mtu = mtu;
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| 187 | s->d1->link_mtu = link_mtu;
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| 188 | }
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| 189 |
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| 190 | s->d1->buffered_messages = buffered_messages;
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| 191 | s->d1->sent_messages = sent_messages;
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| 192 | }
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| 193 |
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| 194 | ssl3_clear(s);
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| 195 |
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| 196 | if (s->method->version == DTLS_ANY_VERSION)
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| 197 | s->version = DTLS_MAX_VERSION;
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| 198 | #ifndef OPENSSL_NO_DTLS1_METHOD
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| 199 | else if (s->options & SSL_OP_CISCO_ANYCONNECT)
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| 200 | s->client_version = s->version = DTLS1_BAD_VER;
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| 201 | #endif
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| 202 | else
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| 203 | s->version = s->method->version;
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| 204 | }
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| 205 |
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| 206 | long dtls1_ctrl(SSL *s, int cmd, long larg, void *parg)
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| 207 | {
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| 208 | int ret = 0;
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| 209 |
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| 210 | switch (cmd) {
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| 211 | case DTLS_CTRL_GET_TIMEOUT:
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| 212 | if (dtls1_get_timeout(s, (struct timeval *)parg) != NULL) {
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| 213 | ret = 1;
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| 214 | }
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| 215 | break;
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| 216 | case DTLS_CTRL_HANDLE_TIMEOUT:
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| 217 | ret = dtls1_handle_timeout(s);
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| 218 | break;
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| 219 | case DTLS_CTRL_SET_LINK_MTU:
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| 220 | if (larg < (long)dtls1_link_min_mtu())
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| 221 | return 0;
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| 222 | s->d1->link_mtu = larg;
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| 223 | return 1;
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| 224 | case DTLS_CTRL_GET_LINK_MIN_MTU:
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| 225 | return (long)dtls1_link_min_mtu();
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| 226 | case SSL_CTRL_SET_MTU:
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| 227 | /*
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| 228 | * We may not have a BIO set yet so can't call dtls1_min_mtu()
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| 229 | * We'll have to make do with dtls1_link_min_mtu() and max overhead
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| 230 | */
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| 231 | if (larg < (long)dtls1_link_min_mtu() - DTLS1_MAX_MTU_OVERHEAD)
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| 232 | return 0;
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| 233 | s->d1->mtu = larg;
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| 234 | return larg;
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| 235 | default:
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| 236 | ret = ssl3_ctrl(s, cmd, larg, parg);
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| 237 | break;
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| 238 | }
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| 239 | return (ret);
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| 240 | }
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| 241 |
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| 242 | void dtls1_start_timer(SSL *s)
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| 243 | {
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| 244 | #ifndef OPENSSL_NO_SCTP
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| 245 | /* Disable timer for SCTP */
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| 246 | if (BIO_dgram_is_sctp(SSL_get_wbio(s))) {
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| 247 | memset(&s->d1->next_timeout, 0, sizeof(s->d1->next_timeout));
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| 248 | return;
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| 249 | }
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| 250 | #endif
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| 251 |
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| 252 | /* If timer is not set, initialize duration with 1 second */
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| 253 | if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0) {
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| 254 | s->d1->timeout_duration = 1;
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| 255 | }
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| 256 |
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| 257 | /* Set timeout to current time */
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| 258 | get_current_time(&(s->d1->next_timeout));
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| 259 |
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| 260 | /* Add duration to current time */
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| 261 | s->d1->next_timeout.tv_sec += s->d1->timeout_duration;
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| 262 | BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0,
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| 263 | &(s->d1->next_timeout));
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| 264 | }
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| 265 |
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| 266 | struct timeval *dtls1_get_timeout(SSL *s, struct timeval *timeleft)
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| 267 | {
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| 268 | struct timeval timenow;
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| 269 |
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| 270 | /* If no timeout is set, just return NULL */
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| 271 | if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0) {
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| 272 | return NULL;
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| 273 | }
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| 274 |
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| 275 | /* Get current time */
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| 276 | get_current_time(&timenow);
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| 277 |
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| 278 | /* If timer already expired, set remaining time to 0 */
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| 279 | if (s->d1->next_timeout.tv_sec < timenow.tv_sec ||
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| 280 | (s->d1->next_timeout.tv_sec == timenow.tv_sec &&
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| 281 | s->d1->next_timeout.tv_usec <= timenow.tv_usec)) {
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| 282 | memset(timeleft, 0, sizeof(*timeleft));
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| 283 | return timeleft;
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| 284 | }
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| 285 |
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| 286 | /* Calculate time left until timer expires */
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| 287 | memcpy(timeleft, &(s->d1->next_timeout), sizeof(struct timeval));
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| 288 | timeleft->tv_sec -= timenow.tv_sec;
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| 289 | timeleft->tv_usec -= timenow.tv_usec;
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| 290 | if (timeleft->tv_usec < 0) {
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| 291 | timeleft->tv_sec--;
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| 292 | timeleft->tv_usec += 1000000;
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| 293 | }
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| 294 |
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| 295 | /*
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| 296 | * If remaining time is less than 15 ms, set it to 0 to prevent issues
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| 297 | * because of small divergences with socket timeouts.
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| 298 | */
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| 299 | if (timeleft->tv_sec == 0 && timeleft->tv_usec < 15000) {
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| 300 | memset(timeleft, 0, sizeof(*timeleft));
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| 301 | }
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| 302 |
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| 303 | return timeleft;
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| 304 | }
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| 305 |
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| 306 | int dtls1_is_timer_expired(SSL *s)
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| 307 | {
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| 308 | struct timeval timeleft;
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| 309 |
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| 310 | /* Get time left until timeout, return false if no timer running */
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| 311 | if (dtls1_get_timeout(s, &timeleft) == NULL) {
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| 312 | return 0;
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| 313 | }
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| 314 |
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| 315 | /* Return false if timer is not expired yet */
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| 316 | if (timeleft.tv_sec > 0 || timeleft.tv_usec > 0) {
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| 317 | return 0;
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| 318 | }
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| 319 |
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| 320 | /* Timer expired, so return true */
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| 321 | return 1;
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| 322 | }
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| 323 |
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| 324 | void dtls1_double_timeout(SSL *s)
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| 325 | {
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| 326 | s->d1->timeout_duration *= 2;
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| 327 | if (s->d1->timeout_duration > 60)
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| 328 | s->d1->timeout_duration = 60;
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| 329 | dtls1_start_timer(s);
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| 330 | }
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| 331 |
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| 332 | void dtls1_stop_timer(SSL *s)
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| 333 | {
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| 334 | /* Reset everything */
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| 335 | memset(&s->d1->timeout, 0, sizeof(s->d1->timeout));
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| 336 | memset(&s->d1->next_timeout, 0, sizeof(s->d1->next_timeout));
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| 337 | s->d1->timeout_duration = 1;
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| 338 | BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0,
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| 339 | &(s->d1->next_timeout));
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| 340 | /* Clear retransmission buffer */
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| 341 | dtls1_clear_sent_buffer(s);
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| 342 | }
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| 343 |
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| 344 | int dtls1_check_timeout_num(SSL *s)
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| 345 | {
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| 346 | unsigned int mtu;
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| 347 |
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| 348 | s->d1->timeout.num_alerts++;
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| 349 |
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| 350 | /* Reduce MTU after 2 unsuccessful retransmissions */
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| 351 | if (s->d1->timeout.num_alerts > 2
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| 352 | && !(SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)) {
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| 353 | mtu =
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| 354 | BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_GET_FALLBACK_MTU, 0, NULL);
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| 355 | if (mtu < s->d1->mtu)
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| 356 | s->d1->mtu = mtu;
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| 357 | }
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| 358 |
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| 359 | if (s->d1->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT) {
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| 360 | /* fail the connection, enough alerts have been sent */
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| 361 | SSLerr(SSL_F_DTLS1_CHECK_TIMEOUT_NUM, SSL_R_READ_TIMEOUT_EXPIRED);
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| 362 | return -1;
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| 363 | }
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| 364 |
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| 365 | return 0;
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| 366 | }
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| 367 |
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| 368 | int dtls1_handle_timeout(SSL *s)
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| 369 | {
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| 370 | /* if no timer is expired, don't do anything */
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| 371 | if (!dtls1_is_timer_expired(s)) {
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| 372 | return 0;
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| 373 | }
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| 374 |
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| 375 | dtls1_double_timeout(s);
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| 376 |
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| 377 | if (dtls1_check_timeout_num(s) < 0)
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| 378 | return -1;
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| 379 |
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| 380 | s->d1->timeout.read_timeouts++;
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| 381 | if (s->d1->timeout.read_timeouts > DTLS1_TMO_READ_COUNT) {
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| 382 | s->d1->timeout.read_timeouts = 1;
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| 383 | }
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| 384 | #ifndef OPENSSL_NO_HEARTBEATS
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| 385 | if (s->tlsext_hb_pending) {
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| 386 | s->tlsext_hb_pending = 0;
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| 387 | return dtls1_heartbeat(s);
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| 388 | }
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| 389 | #endif
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| 390 |
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| 391 | dtls1_start_timer(s);
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| 392 | return dtls1_retransmit_buffered_messages(s);
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| 393 | }
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| 394 |
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| 395 | static void get_current_time(struct timeval *t)
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| 396 | {
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| 397 | #if defined(_WIN32)
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| 398 | SYSTEMTIME st;
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| 399 | union {
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| 400 | unsigned __int64 ul;
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| 401 | FILETIME ft;
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| 402 | } now;
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| 403 |
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| 404 | GetSystemTime(&st);
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| 405 | SystemTimeToFileTime(&st, &now.ft);
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| 406 | /* re-bias to 1/1/1970 */
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| 407 | # ifdef __MINGW32__
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| 408 | now.ul -= 116444736000000000ULL;
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| 409 | # else
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| 410 | /* *INDENT-OFF* */
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| 411 | now.ul -= 116444736000000000UI64;
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| 412 | /* *INDENT-ON* */
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| 413 | # endif
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| 414 | t->tv_sec = (long)(now.ul / 10000000);
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| 415 | t->tv_usec = ((int)(now.ul % 10000000)) / 10;
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| 416 | #elif defined(OPENSSL_SYS_VMS)
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| 417 | struct timeb tb;
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| 418 | ftime(&tb);
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| 419 | t->tv_sec = (long)tb.time;
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| 420 | t->tv_usec = (long)tb.millitm * 1000;
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| 421 | #else
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| 422 | gettimeofday(t, NULL);
|
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| 423 | #endif
|
---|
| 424 | }
|
---|
| 425 |
|
---|
| 426 | #define LISTEN_SUCCESS 2
|
---|
| 427 | #define LISTEN_SEND_VERIFY_REQUEST 1
|
---|
| 428 |
|
---|
| 429 | #ifndef OPENSSL_NO_SOCK
|
---|
| 430 | int DTLSv1_listen(SSL *s, BIO_ADDR *client)
|
---|
| 431 | {
|
---|
| 432 | int next, n, ret = 0, clearpkt = 0;
|
---|
| 433 | unsigned char cookie[DTLS1_COOKIE_LENGTH];
|
---|
| 434 | unsigned char seq[SEQ_NUM_SIZE];
|
---|
| 435 | const unsigned char *data;
|
---|
| 436 | unsigned char *p, *buf;
|
---|
| 437 | unsigned long reclen, fragoff, fraglen, msglen;
|
---|
| 438 | unsigned int rectype, versmajor, msgseq, msgtype, clientvers, cookielen;
|
---|
| 439 | BIO *rbio, *wbio;
|
---|
| 440 | BUF_MEM *bufm;
|
---|
| 441 | BIO_ADDR *tmpclient = NULL;
|
---|
| 442 | PACKET pkt, msgpkt, msgpayload, session, cookiepkt;
|
---|
| 443 |
|
---|
| 444 | if (s->handshake_func == NULL) {
|
---|
| 445 | /* Not properly initialized yet */
|
---|
| 446 | SSL_set_accept_state(s);
|
---|
| 447 | }
|
---|
| 448 |
|
---|
| 449 | /* Ensure there is no state left over from a previous invocation */
|
---|
| 450 | if (!SSL_clear(s))
|
---|
| 451 | return -1;
|
---|
| 452 |
|
---|
| 453 | ERR_clear_error();
|
---|
| 454 |
|
---|
| 455 | rbio = SSL_get_rbio(s);
|
---|
| 456 | wbio = SSL_get_wbio(s);
|
---|
| 457 |
|
---|
| 458 | if (!rbio || !wbio) {
|
---|
| 459 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_BIO_NOT_SET);
|
---|
| 460 | return -1;
|
---|
| 461 | }
|
---|
| 462 |
|
---|
| 463 | /*
|
---|
| 464 | * We only peek at incoming ClientHello's until we're sure we are going to
|
---|
| 465 | * to respond with a HelloVerifyRequest. If its a ClientHello with a valid
|
---|
| 466 | * cookie then we leave it in the BIO for accept to handle.
|
---|
| 467 | */
|
---|
| 468 | BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 1, NULL);
|
---|
| 469 |
|
---|
| 470 | /*
|
---|
| 471 | * Note: This check deliberately excludes DTLS1_BAD_VER because that version
|
---|
| 472 | * requires the MAC to be calculated *including* the first ClientHello
|
---|
| 473 | * (without the cookie). Since DTLSv1_listen is stateless that cannot be
|
---|
| 474 | * supported. DTLS1_BAD_VER must use cookies in a stateful manner (e.g. via
|
---|
| 475 | * SSL_accept)
|
---|
| 476 | */
|
---|
| 477 | if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00)) {
|
---|
| 478 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_UNSUPPORTED_SSL_VERSION);
|
---|
| 479 | return -1;
|
---|
| 480 | }
|
---|
| 481 |
|
---|
| 482 | if (s->init_buf == NULL) {
|
---|
| 483 | if ((bufm = BUF_MEM_new()) == NULL) {
|
---|
| 484 | SSLerr(SSL_F_DTLSV1_LISTEN, ERR_R_MALLOC_FAILURE);
|
---|
| 485 | return -1;
|
---|
| 486 | }
|
---|
| 487 |
|
---|
| 488 | if (!BUF_MEM_grow(bufm, SSL3_RT_MAX_PLAIN_LENGTH)) {
|
---|
| 489 | BUF_MEM_free(bufm);
|
---|
| 490 | SSLerr(SSL_F_DTLSV1_LISTEN, ERR_R_MALLOC_FAILURE);
|
---|
| 491 | return -1;
|
---|
| 492 | }
|
---|
| 493 | s->init_buf = bufm;
|
---|
| 494 | }
|
---|
| 495 | buf = (unsigned char *)s->init_buf->data;
|
---|
| 496 |
|
---|
| 497 | do {
|
---|
| 498 | /* Get a packet */
|
---|
| 499 |
|
---|
| 500 | clear_sys_error();
|
---|
| 501 | /*
|
---|
| 502 | * Technically a ClientHello could be SSL3_RT_MAX_PLAIN_LENGTH
|
---|
| 503 | * + DTLS1_RT_HEADER_LENGTH bytes long. Normally init_buf does not store
|
---|
| 504 | * the record header as well, but we do here. We've set up init_buf to
|
---|
| 505 | * be the standard size for simplicity. In practice we shouldn't ever
|
---|
| 506 | * receive a ClientHello as long as this. If we do it will get dropped
|
---|
| 507 | * in the record length check below.
|
---|
| 508 | */
|
---|
| 509 | n = BIO_read(rbio, buf, SSL3_RT_MAX_PLAIN_LENGTH);
|
---|
| 510 |
|
---|
| 511 | if (n <= 0) {
|
---|
| 512 | if (BIO_should_retry(rbio)) {
|
---|
| 513 | /* Non-blocking IO */
|
---|
| 514 | goto end;
|
---|
| 515 | }
|
---|
| 516 | return -1;
|
---|
| 517 | }
|
---|
| 518 |
|
---|
| 519 | /* If we hit any problems we need to clear this packet from the BIO */
|
---|
| 520 | clearpkt = 1;
|
---|
| 521 |
|
---|
| 522 | if (!PACKET_buf_init(&pkt, buf, n)) {
|
---|
| 523 | SSLerr(SSL_F_DTLSV1_LISTEN, ERR_R_INTERNAL_ERROR);
|
---|
| 524 | return -1;
|
---|
| 525 | }
|
---|
| 526 |
|
---|
| 527 | /*
|
---|
| 528 | * Parse the received record. If there are any problems with it we just
|
---|
| 529 | * dump it - with no alert. RFC6347 says this "Unlike TLS, DTLS is
|
---|
| 530 | * resilient in the face of invalid records (e.g., invalid formatting,
|
---|
| 531 | * length, MAC, etc.). In general, invalid records SHOULD be silently
|
---|
| 532 | * discarded, thus preserving the association; however, an error MAY be
|
---|
| 533 | * logged for diagnostic purposes."
|
---|
| 534 | */
|
---|
| 535 |
|
---|
| 536 | /* this packet contained a partial record, dump it */
|
---|
| 537 | if (n < DTLS1_RT_HEADER_LENGTH) {
|
---|
| 538 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_RECORD_TOO_SMALL);
|
---|
| 539 | goto end;
|
---|
| 540 | }
|
---|
| 541 |
|
---|
| 542 | if (s->msg_callback)
|
---|
| 543 | s->msg_callback(0, 0, SSL3_RT_HEADER, buf,
|
---|
| 544 | DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
|
---|
| 545 |
|
---|
| 546 | /* Get the record header */
|
---|
| 547 | if (!PACKET_get_1(&pkt, &rectype)
|
---|
| 548 | || !PACKET_get_1(&pkt, &versmajor)) {
|
---|
| 549 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
|
---|
| 550 | goto end;
|
---|
| 551 | }
|
---|
| 552 |
|
---|
| 553 | if (rectype != SSL3_RT_HANDSHAKE) {
|
---|
| 554 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_UNEXPECTED_MESSAGE);
|
---|
| 555 | goto end;
|
---|
| 556 | }
|
---|
| 557 |
|
---|
| 558 | /*
|
---|
| 559 | * Check record version number. We only check that the major version is
|
---|
| 560 | * the same.
|
---|
| 561 | */
|
---|
| 562 | if (versmajor != DTLS1_VERSION_MAJOR) {
|
---|
| 563 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_BAD_PROTOCOL_VERSION_NUMBER);
|
---|
| 564 | goto end;
|
---|
| 565 | }
|
---|
| 566 |
|
---|
| 567 | if (!PACKET_forward(&pkt, 1)
|
---|
| 568 | /* Save the sequence number: 64 bits, with top 2 bytes = epoch */
|
---|
| 569 | || !PACKET_copy_bytes(&pkt, seq, SEQ_NUM_SIZE)
|
---|
| 570 | || !PACKET_get_length_prefixed_2(&pkt, &msgpkt)) {
|
---|
| 571 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
|
---|
| 572 | goto end;
|
---|
| 573 | }
|
---|
| 574 | /*
|
---|
| 575 | * We allow data remaining at the end of the packet because there could
|
---|
| 576 | * be a second record (but we ignore it)
|
---|
| 577 | */
|
---|
| 578 |
|
---|
| 579 | /* This is an initial ClientHello so the epoch has to be 0 */
|
---|
| 580 | if (seq[0] != 0 || seq[1] != 0) {
|
---|
| 581 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_UNEXPECTED_MESSAGE);
|
---|
| 582 | goto end;
|
---|
| 583 | }
|
---|
| 584 |
|
---|
| 585 | /* Get a pointer to the raw message for the later callback */
|
---|
| 586 | data = PACKET_data(&msgpkt);
|
---|
| 587 |
|
---|
| 588 | /* Finished processing the record header, now process the message */
|
---|
| 589 | if (!PACKET_get_1(&msgpkt, &msgtype)
|
---|
| 590 | || !PACKET_get_net_3(&msgpkt, &msglen)
|
---|
| 591 | || !PACKET_get_net_2(&msgpkt, &msgseq)
|
---|
| 592 | || !PACKET_get_net_3(&msgpkt, &fragoff)
|
---|
| 593 | || !PACKET_get_net_3(&msgpkt, &fraglen)
|
---|
| 594 | || !PACKET_get_sub_packet(&msgpkt, &msgpayload, fraglen)
|
---|
| 595 | || PACKET_remaining(&msgpkt) != 0) {
|
---|
| 596 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
|
---|
| 597 | goto end;
|
---|
| 598 | }
|
---|
| 599 |
|
---|
| 600 | if (msgtype != SSL3_MT_CLIENT_HELLO) {
|
---|
| 601 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_UNEXPECTED_MESSAGE);
|
---|
| 602 | goto end;
|
---|
| 603 | }
|
---|
| 604 |
|
---|
| 605 | /* Message sequence number can only be 0 or 1 */
|
---|
| 606 | if (msgseq > 2) {
|
---|
| 607 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_INVALID_SEQUENCE_NUMBER);
|
---|
| 608 | goto end;
|
---|
| 609 | }
|
---|
| 610 |
|
---|
| 611 | /*
|
---|
| 612 | * We don't support fragment reassembly for ClientHellos whilst
|
---|
| 613 | * listening because that would require server side state (which is
|
---|
| 614 | * against the whole point of the ClientHello/HelloVerifyRequest
|
---|
| 615 | * mechanism). Instead we only look at the first ClientHello fragment
|
---|
| 616 | * and require that the cookie must be contained within it.
|
---|
| 617 | */
|
---|
| 618 | if (fragoff != 0 || fraglen > msglen) {
|
---|
| 619 | /* Non initial ClientHello fragment (or bad fragment) */
|
---|
| 620 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_FRAGMENTED_CLIENT_HELLO);
|
---|
| 621 | goto end;
|
---|
| 622 | }
|
---|
| 623 |
|
---|
| 624 | if (s->msg_callback)
|
---|
| 625 | s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, data,
|
---|
| 626 | fraglen + DTLS1_HM_HEADER_LENGTH, s,
|
---|
| 627 | s->msg_callback_arg);
|
---|
| 628 |
|
---|
| 629 | if (!PACKET_get_net_2(&msgpayload, &clientvers)) {
|
---|
| 630 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
|
---|
| 631 | goto end;
|
---|
| 632 | }
|
---|
| 633 |
|
---|
| 634 | /*
|
---|
| 635 | * Verify client version is supported
|
---|
| 636 | */
|
---|
| 637 | if (DTLS_VERSION_LT(clientvers, (unsigned int)s->method->version) &&
|
---|
| 638 | s->method->version != DTLS_ANY_VERSION) {
|
---|
| 639 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_WRONG_VERSION_NUMBER);
|
---|
| 640 | goto end;
|
---|
| 641 | }
|
---|
| 642 |
|
---|
| 643 | if (!PACKET_forward(&msgpayload, SSL3_RANDOM_SIZE)
|
---|
| 644 | || !PACKET_get_length_prefixed_1(&msgpayload, &session)
|
---|
| 645 | || !PACKET_get_length_prefixed_1(&msgpayload, &cookiepkt)) {
|
---|
| 646 | /*
|
---|
| 647 | * Could be malformed or the cookie does not fit within the initial
|
---|
| 648 | * ClientHello fragment. Either way we can't handle it.
|
---|
| 649 | */
|
---|
| 650 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_LENGTH_MISMATCH);
|
---|
| 651 | goto end;
|
---|
| 652 | }
|
---|
| 653 |
|
---|
| 654 | /*
|
---|
| 655 | * Check if we have a cookie or not. If not we need to send a
|
---|
| 656 | * HelloVerifyRequest.
|
---|
| 657 | */
|
---|
| 658 | if (PACKET_remaining(&cookiepkt) == 0) {
|
---|
| 659 | next = LISTEN_SEND_VERIFY_REQUEST;
|
---|
| 660 | } else {
|
---|
| 661 | /*
|
---|
| 662 | * We have a cookie, so lets check it.
|
---|
| 663 | */
|
---|
| 664 | if (s->ctx->app_verify_cookie_cb == NULL) {
|
---|
| 665 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_NO_VERIFY_COOKIE_CALLBACK);
|
---|
| 666 | /* This is fatal */
|
---|
| 667 | return -1;
|
---|
| 668 | }
|
---|
| 669 | if (s->ctx->app_verify_cookie_cb(s, PACKET_data(&cookiepkt),
|
---|
| 670 | PACKET_remaining(&cookiepkt)) ==
|
---|
| 671 | 0) {
|
---|
| 672 | /*
|
---|
| 673 | * We treat invalid cookies in the same was as no cookie as
|
---|
| 674 | * per RFC6347
|
---|
| 675 | */
|
---|
| 676 | next = LISTEN_SEND_VERIFY_REQUEST;
|
---|
| 677 | } else {
|
---|
| 678 | /* Cookie verification succeeded */
|
---|
| 679 | next = LISTEN_SUCCESS;
|
---|
| 680 | }
|
---|
| 681 | }
|
---|
| 682 |
|
---|
| 683 | if (next == LISTEN_SEND_VERIFY_REQUEST) {
|
---|
| 684 | /*
|
---|
| 685 | * There was no cookie in the ClientHello so we need to send a
|
---|
| 686 | * HelloVerifyRequest. If this fails we do not worry about trying
|
---|
| 687 | * to resend, we just drop it.
|
---|
| 688 | */
|
---|
| 689 |
|
---|
| 690 | /*
|
---|
| 691 | * Dump the read packet, we don't need it any more. Ignore return
|
---|
| 692 | * value
|
---|
| 693 | */
|
---|
| 694 | BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 0, NULL);
|
---|
| 695 | BIO_read(rbio, buf, SSL3_RT_MAX_PLAIN_LENGTH);
|
---|
| 696 | BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 1, NULL);
|
---|
| 697 |
|
---|
| 698 | /* Generate the cookie */
|
---|
| 699 | if (s->ctx->app_gen_cookie_cb == NULL ||
|
---|
| 700 | s->ctx->app_gen_cookie_cb(s, cookie, &cookielen) == 0 ||
|
---|
| 701 | cookielen > 255) {
|
---|
| 702 | SSLerr(SSL_F_DTLSV1_LISTEN, SSL_R_COOKIE_GEN_CALLBACK_FAILURE);
|
---|
| 703 | /* This is fatal */
|
---|
| 704 | return -1;
|
---|
| 705 | }
|
---|
| 706 |
|
---|
| 707 | p = &buf[DTLS1_RT_HEADER_LENGTH];
|
---|
| 708 | msglen = dtls_raw_hello_verify_request(p + DTLS1_HM_HEADER_LENGTH,
|
---|
| 709 | cookie, cookielen);
|
---|
| 710 |
|
---|
| 711 | *p++ = DTLS1_MT_HELLO_VERIFY_REQUEST;
|
---|
| 712 |
|
---|
| 713 | /* Message length */
|
---|
| 714 | l2n3(msglen, p);
|
---|
| 715 |
|
---|
| 716 | /* Message sequence number is always 0 for a HelloVerifyRequest */
|
---|
| 717 | s2n(0, p);
|
---|
| 718 |
|
---|
| 719 | /*
|
---|
| 720 | * We never fragment a HelloVerifyRequest, so fragment offset is 0
|
---|
| 721 | * and fragment length is message length
|
---|
| 722 | */
|
---|
| 723 | l2n3(0, p);
|
---|
| 724 | l2n3(msglen, p);
|
---|
| 725 |
|
---|
| 726 | /* Set reclen equal to length of whole handshake message */
|
---|
| 727 | reclen = msglen + DTLS1_HM_HEADER_LENGTH;
|
---|
| 728 |
|
---|
| 729 | /* Add the record header */
|
---|
| 730 | p = buf;
|
---|
| 731 |
|
---|
| 732 | *(p++) = SSL3_RT_HANDSHAKE;
|
---|
| 733 | /*
|
---|
| 734 | * Special case: for hello verify request, client version 1.0 and we
|
---|
| 735 | * haven't decided which version to use yet send back using version
|
---|
| 736 | * 1.0 header: otherwise some clients will ignore it.
|
---|
| 737 | */
|
---|
| 738 | if (s->method->version == DTLS_ANY_VERSION) {
|
---|
| 739 | *(p++) = DTLS1_VERSION >> 8;
|
---|
| 740 | *(p++) = DTLS1_VERSION & 0xff;
|
---|
| 741 | } else {
|
---|
| 742 | *(p++) = s->version >> 8;
|
---|
| 743 | *(p++) = s->version & 0xff;
|
---|
| 744 | }
|
---|
| 745 |
|
---|
| 746 | /*
|
---|
| 747 | * Record sequence number is always the same as in the received
|
---|
| 748 | * ClientHello
|
---|
| 749 | */
|
---|
| 750 | memcpy(p, seq, SEQ_NUM_SIZE);
|
---|
| 751 | p += SEQ_NUM_SIZE;
|
---|
| 752 |
|
---|
| 753 | /* Length */
|
---|
| 754 | s2n(reclen, p);
|
---|
| 755 |
|
---|
| 756 | /*
|
---|
| 757 | * Set reclen equal to length of whole record including record
|
---|
| 758 | * header
|
---|
| 759 | */
|
---|
| 760 | reclen += DTLS1_RT_HEADER_LENGTH;
|
---|
| 761 |
|
---|
| 762 | if (s->msg_callback)
|
---|
| 763 | s->msg_callback(1, 0, SSL3_RT_HEADER, buf,
|
---|
| 764 | DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
|
---|
| 765 |
|
---|
| 766 | if ((tmpclient = BIO_ADDR_new()) == NULL) {
|
---|
| 767 | SSLerr(SSL_F_DTLSV1_LISTEN, ERR_R_MALLOC_FAILURE);
|
---|
| 768 | goto end;
|
---|
| 769 | }
|
---|
| 770 |
|
---|
| 771 | /*
|
---|
| 772 | * This is unnecessary if rbio and wbio are one and the same - but
|
---|
| 773 | * maybe they're not. We ignore errors here - some BIOs do not
|
---|
| 774 | * support this.
|
---|
| 775 | */
|
---|
| 776 | if (BIO_dgram_get_peer(rbio, tmpclient) > 0) {
|
---|
| 777 | (void)BIO_dgram_set_peer(wbio, tmpclient);
|
---|
| 778 | }
|
---|
| 779 | BIO_ADDR_free(tmpclient);
|
---|
| 780 | tmpclient = NULL;
|
---|
| 781 |
|
---|
| 782 | if (BIO_write(wbio, buf, reclen) < (int)reclen) {
|
---|
| 783 | if (BIO_should_retry(wbio)) {
|
---|
| 784 | /*
|
---|
| 785 | * Non-blocking IO...but we're stateless, so we're just
|
---|
| 786 | * going to drop this packet.
|
---|
| 787 | */
|
---|
| 788 | goto end;
|
---|
| 789 | }
|
---|
| 790 | return -1;
|
---|
| 791 | }
|
---|
| 792 |
|
---|
| 793 | if (BIO_flush(wbio) <= 0) {
|
---|
| 794 | if (BIO_should_retry(wbio)) {
|
---|
| 795 | /*
|
---|
| 796 | * Non-blocking IO...but we're stateless, so we're just
|
---|
| 797 | * going to drop this packet.
|
---|
| 798 | */
|
---|
| 799 | goto end;
|
---|
| 800 | }
|
---|
| 801 | return -1;
|
---|
| 802 | }
|
---|
| 803 | }
|
---|
| 804 | } while (next != LISTEN_SUCCESS);
|
---|
| 805 |
|
---|
| 806 | /*
|
---|
| 807 | * Set expected sequence numbers to continue the handshake.
|
---|
| 808 | */
|
---|
| 809 | s->d1->handshake_read_seq = 1;
|
---|
| 810 | s->d1->handshake_write_seq = 1;
|
---|
| 811 | s->d1->next_handshake_write_seq = 1;
|
---|
| 812 | DTLS_RECORD_LAYER_set_write_sequence(&s->rlayer, seq);
|
---|
| 813 |
|
---|
| 814 | /*
|
---|
| 815 | * We are doing cookie exchange, so make sure we set that option in the
|
---|
| 816 | * SSL object
|
---|
| 817 | */
|
---|
| 818 | SSL_set_options(s, SSL_OP_COOKIE_EXCHANGE);
|
---|
| 819 |
|
---|
| 820 | /*
|
---|
| 821 | * Tell the state machine that we've done the initial hello verify
|
---|
| 822 | * exchange
|
---|
| 823 | */
|
---|
| 824 | ossl_statem_set_hello_verify_done(s);
|
---|
| 825 |
|
---|
| 826 | /*
|
---|
| 827 | * Some BIOs may not support this. If we fail we clear the client address
|
---|
| 828 | */
|
---|
| 829 | if (BIO_dgram_get_peer(rbio, client) <= 0)
|
---|
| 830 | BIO_ADDR_clear(client);
|
---|
| 831 |
|
---|
| 832 | ret = 1;
|
---|
| 833 | clearpkt = 0;
|
---|
| 834 | end:
|
---|
| 835 | BIO_ADDR_free(tmpclient);
|
---|
| 836 | BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_PEEK_MODE, 0, NULL);
|
---|
| 837 | if (clearpkt) {
|
---|
| 838 | /* Dump this packet. Ignore return value */
|
---|
| 839 | BIO_read(rbio, buf, SSL3_RT_MAX_PLAIN_LENGTH);
|
---|
| 840 | }
|
---|
| 841 | return ret;
|
---|
| 842 | }
|
---|
| 843 | #endif
|
---|
| 844 |
|
---|
| 845 | static int dtls1_set_handshake_header(SSL *s, int htype, unsigned long len)
|
---|
| 846 | {
|
---|
| 847 | dtls1_set_message_header(s, htype, len, 0, len);
|
---|
| 848 | s->init_num = (int)len + DTLS1_HM_HEADER_LENGTH;
|
---|
| 849 | s->init_off = 0;
|
---|
| 850 | /* Buffer the message to handle re-xmits */
|
---|
| 851 |
|
---|
| 852 | if (!dtls1_buffer_message(s, 0))
|
---|
| 853 | return 0;
|
---|
| 854 |
|
---|
| 855 | return 1;
|
---|
| 856 | }
|
---|
| 857 |
|
---|
| 858 | static int dtls1_handshake_write(SSL *s)
|
---|
| 859 | {
|
---|
| 860 | return dtls1_do_write(s, SSL3_RT_HANDSHAKE);
|
---|
| 861 | }
|
---|
| 862 |
|
---|
| 863 | #ifndef OPENSSL_NO_HEARTBEATS
|
---|
| 864 |
|
---|
| 865 | # define HEARTBEAT_SIZE(payload, padding) ( \
|
---|
| 866 | 1 /* heartbeat type */ + \
|
---|
| 867 | 2 /* heartbeat length */ + \
|
---|
| 868 | (payload) + (padding))
|
---|
| 869 |
|
---|
| 870 | # define HEARTBEAT_SIZE_STD(payload) HEARTBEAT_SIZE(payload, 16)
|
---|
| 871 |
|
---|
| 872 | int dtls1_process_heartbeat(SSL *s, unsigned char *p, unsigned int length)
|
---|
| 873 | {
|
---|
| 874 | unsigned char *pl;
|
---|
| 875 | unsigned short hbtype;
|
---|
| 876 | unsigned int payload;
|
---|
| 877 | unsigned int padding = 16; /* Use minimum padding */
|
---|
| 878 |
|
---|
| 879 | if (s->msg_callback)
|
---|
| 880 | s->msg_callback(0, s->version, DTLS1_RT_HEARTBEAT,
|
---|
| 881 | p, length, s, s->msg_callback_arg);
|
---|
| 882 |
|
---|
| 883 | /* Read type and payload length */
|
---|
| 884 | if (HEARTBEAT_SIZE_STD(0) > length)
|
---|
| 885 | return 0; /* silently discard */
|
---|
| 886 | if (length > SSL3_RT_MAX_PLAIN_LENGTH)
|
---|
| 887 | return 0; /* silently discard per RFC 6520 sec. 4 */
|
---|
| 888 |
|
---|
| 889 | hbtype = *p++;
|
---|
| 890 | n2s(p, payload);
|
---|
| 891 | if (HEARTBEAT_SIZE_STD(payload) > length)
|
---|
| 892 | return 0; /* silently discard per RFC 6520 sec. 4 */
|
---|
| 893 | pl = p;
|
---|
| 894 |
|
---|
| 895 | if (hbtype == TLS1_HB_REQUEST) {
|
---|
| 896 | unsigned char *buffer, *bp;
|
---|
| 897 | unsigned int write_length = HEARTBEAT_SIZE(payload, padding);
|
---|
| 898 | int r;
|
---|
| 899 |
|
---|
| 900 | if (write_length > SSL3_RT_MAX_PLAIN_LENGTH)
|
---|
| 901 | return 0;
|
---|
| 902 |
|
---|
| 903 | /* Allocate memory for the response. */
|
---|
| 904 | buffer = OPENSSL_malloc(write_length);
|
---|
| 905 | if (buffer == NULL)
|
---|
| 906 | return -1;
|
---|
| 907 | bp = buffer;
|
---|
| 908 |
|
---|
| 909 | /* Enter response type, length and copy payload */
|
---|
| 910 | *bp++ = TLS1_HB_RESPONSE;
|
---|
| 911 | s2n(payload, bp);
|
---|
| 912 | memcpy(bp, pl, payload);
|
---|
| 913 | bp += payload;
|
---|
| 914 | /* Random padding */
|
---|
| 915 | if (RAND_bytes(bp, padding) <= 0) {
|
---|
| 916 | OPENSSL_free(buffer);
|
---|
| 917 | return -1;
|
---|
| 918 | }
|
---|
| 919 |
|
---|
| 920 | r = dtls1_write_bytes(s, DTLS1_RT_HEARTBEAT, buffer, write_length);
|
---|
| 921 |
|
---|
| 922 | if (r >= 0 && s->msg_callback)
|
---|
| 923 | s->msg_callback(1, s->version, DTLS1_RT_HEARTBEAT,
|
---|
| 924 | buffer, write_length, s, s->msg_callback_arg);
|
---|
| 925 |
|
---|
| 926 | OPENSSL_free(buffer);
|
---|
| 927 |
|
---|
| 928 | if (r < 0)
|
---|
| 929 | return r;
|
---|
| 930 | } else if (hbtype == TLS1_HB_RESPONSE) {
|
---|
| 931 | unsigned int seq;
|
---|
| 932 |
|
---|
| 933 | /*
|
---|
| 934 | * We only send sequence numbers (2 bytes unsigned int), and 16
|
---|
| 935 | * random bytes, so we just try to read the sequence number
|
---|
| 936 | */
|
---|
| 937 | n2s(pl, seq);
|
---|
| 938 |
|
---|
| 939 | if (payload == 18 && seq == s->tlsext_hb_seq) {
|
---|
| 940 | dtls1_stop_timer(s);
|
---|
| 941 | s->tlsext_hb_seq++;
|
---|
| 942 | s->tlsext_hb_pending = 0;
|
---|
| 943 | }
|
---|
| 944 | }
|
---|
| 945 |
|
---|
| 946 | return 0;
|
---|
| 947 | }
|
---|
| 948 |
|
---|
| 949 | int dtls1_heartbeat(SSL *s)
|
---|
| 950 | {
|
---|
| 951 | unsigned char *buf, *p;
|
---|
| 952 | int ret = -1;
|
---|
| 953 | unsigned int payload = 18; /* Sequence number + random bytes */
|
---|
| 954 | unsigned int padding = 16; /* Use minimum padding */
|
---|
| 955 | unsigned int size;
|
---|
| 956 |
|
---|
| 957 | /* Only send if peer supports and accepts HB requests... */
|
---|
| 958 | if (!(s->tlsext_heartbeat & SSL_DTLSEXT_HB_ENABLED) ||
|
---|
| 959 | s->tlsext_heartbeat & SSL_DTLSEXT_HB_DONT_SEND_REQUESTS) {
|
---|
| 960 | SSLerr(SSL_F_DTLS1_HEARTBEAT, SSL_R_TLS_HEARTBEAT_PEER_DOESNT_ACCEPT);
|
---|
| 961 | return -1;
|
---|
| 962 | }
|
---|
| 963 |
|
---|
| 964 | /* ...and there is none in flight yet... */
|
---|
| 965 | if (s->tlsext_hb_pending) {
|
---|
| 966 | SSLerr(SSL_F_DTLS1_HEARTBEAT, SSL_R_TLS_HEARTBEAT_PENDING);
|
---|
| 967 | return -1;
|
---|
| 968 | }
|
---|
| 969 |
|
---|
| 970 | /* ...and no handshake in progress. */
|
---|
| 971 | if (SSL_in_init(s) || ossl_statem_get_in_handshake(s)) {
|
---|
| 972 | SSLerr(SSL_F_DTLS1_HEARTBEAT, SSL_R_UNEXPECTED_MESSAGE);
|
---|
| 973 | return -1;
|
---|
| 974 | }
|
---|
| 975 |
|
---|
| 976 | /*-
|
---|
| 977 | * Create HeartBeat message, we just use a sequence number
|
---|
| 978 | * as payload to distinguish different messages and add
|
---|
| 979 | * some random stuff.
|
---|
| 980 | */
|
---|
| 981 | size = HEARTBEAT_SIZE(payload, padding);
|
---|
| 982 | buf = OPENSSL_malloc(size);
|
---|
| 983 | if (buf == NULL) {
|
---|
| 984 | SSLerr(SSL_F_DTLS1_HEARTBEAT, ERR_R_MALLOC_FAILURE);
|
---|
| 985 | return -1;
|
---|
| 986 | }
|
---|
| 987 | p = buf;
|
---|
| 988 | /* Message Type */
|
---|
| 989 | *p++ = TLS1_HB_REQUEST;
|
---|
| 990 | /* Payload length (18 bytes here) */
|
---|
| 991 | s2n(payload, p);
|
---|
| 992 | /* Sequence number */
|
---|
| 993 | s2n(s->tlsext_hb_seq, p);
|
---|
| 994 | /* 16 random bytes */
|
---|
| 995 | if (RAND_bytes(p, 16) <= 0) {
|
---|
| 996 | SSLerr(SSL_F_DTLS1_HEARTBEAT, ERR_R_INTERNAL_ERROR);
|
---|
| 997 | goto err;
|
---|
| 998 | }
|
---|
| 999 | p += 16;
|
---|
| 1000 | /* Random padding */
|
---|
| 1001 | if (RAND_bytes(p, padding) <= 0) {
|
---|
| 1002 | SSLerr(SSL_F_DTLS1_HEARTBEAT, ERR_R_INTERNAL_ERROR);
|
---|
| 1003 | goto err;
|
---|
| 1004 | }
|
---|
| 1005 |
|
---|
| 1006 | ret = dtls1_write_bytes(s, DTLS1_RT_HEARTBEAT, buf, size);
|
---|
| 1007 | if (ret >= 0) {
|
---|
| 1008 | if (s->msg_callback)
|
---|
| 1009 | s->msg_callback(1, s->version, DTLS1_RT_HEARTBEAT,
|
---|
| 1010 | buf, size, s, s->msg_callback_arg);
|
---|
| 1011 |
|
---|
| 1012 | dtls1_start_timer(s);
|
---|
| 1013 | s->tlsext_hb_pending = 1;
|
---|
| 1014 | }
|
---|
| 1015 |
|
---|
| 1016 | err:
|
---|
| 1017 | OPENSSL_free(buf);
|
---|
| 1018 |
|
---|
| 1019 | return ret;
|
---|
| 1020 | }
|
---|
| 1021 | #endif
|
---|
| 1022 |
|
---|
| 1023 | int dtls1_shutdown(SSL *s)
|
---|
| 1024 | {
|
---|
| 1025 | int ret;
|
---|
| 1026 | #ifndef OPENSSL_NO_SCTP
|
---|
| 1027 | BIO *wbio;
|
---|
| 1028 |
|
---|
| 1029 | wbio = SSL_get_wbio(s);
|
---|
| 1030 | if (wbio != NULL && BIO_dgram_is_sctp(wbio) &&
|
---|
| 1031 | !(s->shutdown & SSL_SENT_SHUTDOWN)) {
|
---|
| 1032 | ret = BIO_dgram_sctp_wait_for_dry(wbio);
|
---|
| 1033 | if (ret < 0)
|
---|
| 1034 | return -1;
|
---|
| 1035 |
|
---|
| 1036 | if (ret == 0)
|
---|
| 1037 | BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN, 1,
|
---|
| 1038 | NULL);
|
---|
| 1039 | }
|
---|
| 1040 | #endif
|
---|
| 1041 | ret = ssl3_shutdown(s);
|
---|
| 1042 | #ifndef OPENSSL_NO_SCTP
|
---|
| 1043 | BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN, 0, NULL);
|
---|
| 1044 | #endif
|
---|
| 1045 | return ret;
|
---|
| 1046 | }
|
---|
| 1047 |
|
---|
| 1048 | int dtls1_query_mtu(SSL *s)
|
---|
| 1049 | {
|
---|
| 1050 | if (s->d1->link_mtu) {
|
---|
| 1051 | s->d1->mtu =
|
---|
| 1052 | s->d1->link_mtu - BIO_dgram_get_mtu_overhead(SSL_get_wbio(s));
|
---|
| 1053 | s->d1->link_mtu = 0;
|
---|
| 1054 | }
|
---|
| 1055 |
|
---|
| 1056 | /* AHA! Figure out the MTU, and stick to the right size */
|
---|
| 1057 | if (s->d1->mtu < dtls1_min_mtu(s)) {
|
---|
| 1058 | if (!(SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)) {
|
---|
| 1059 | s->d1->mtu =
|
---|
| 1060 | BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);
|
---|
| 1061 |
|
---|
| 1062 | /*
|
---|
| 1063 | * I've seen the kernel return bogus numbers when it doesn't know
|
---|
| 1064 | * (initial write), so just make sure we have a reasonable number
|
---|
| 1065 | */
|
---|
| 1066 | if (s->d1->mtu < dtls1_min_mtu(s)) {
|
---|
| 1067 | /* Set to min mtu */
|
---|
| 1068 | s->d1->mtu = dtls1_min_mtu(s);
|
---|
| 1069 | BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SET_MTU,
|
---|
| 1070 | s->d1->mtu, NULL);
|
---|
| 1071 | }
|
---|
| 1072 | } else
|
---|
| 1073 | return 0;
|
---|
| 1074 | }
|
---|
| 1075 | return 1;
|
---|
| 1076 | }
|
---|
| 1077 |
|
---|
| 1078 | static unsigned int dtls1_link_min_mtu(void)
|
---|
| 1079 | {
|
---|
| 1080 | return (g_probable_mtu[(sizeof(g_probable_mtu) /
|
---|
| 1081 | sizeof(g_probable_mtu[0])) - 1]);
|
---|
| 1082 | }
|
---|
| 1083 |
|
---|
| 1084 | unsigned int dtls1_min_mtu(SSL *s)
|
---|
| 1085 | {
|
---|
| 1086 | return dtls1_link_min_mtu() - BIO_dgram_get_mtu_overhead(SSL_get_wbio(s));
|
---|
| 1087 | }
|
---|