1 /* $OpenBSD: cipher_list.c,v 1.9 2018/06/02 16:35:02 jsing Exp $ */ 2 /* 3 * Copyright (c) 2015 Doug Hogan <doug@openbsd.org> 4 * Copyright (c) 2015 Joel Sing <jsing@openbsd.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 /* 20 * Test TLS ssl bytes (aka cipher suites) to cipher list and back. 21 * 22 * TLSv1.0 - RFC 2246 section 7.4.1.2 (ClientHello struct) 23 * TLSv1.1 - RFC 4346 section 7.4.1.2 (ClientHello struct) 24 * TLSv1.2 - RFC 5246 section 7.4.1.2 (ClientHello struct) 25 * 26 * In all of these standards, the relevant structures are: 27 * 28 * uint8 CipherSuite[2]; 29 * 30 * struct { 31 * ... 32 * CipherSuite cipher_suites<2..2^16-2> 33 * ... 34 * } ClientHello; 35 */ 36 37 #include <openssl/ssl.h> 38 39 #include <stdio.h> 40 #include <string.h> 41 42 #include "ssl_locl.h" 43 44 #include "tests.h" 45 46 static uint8_t cipher_bytes[] = { 47 0xcc, 0xa8, /* ECDHE-ECDSA-CHACHA20-POLY1305 */ 48 0xcc, 0xa9, /* ECDHE-RSA-CHACHA20-POLY1305 */ 49 0xcc, 0xaa, /* DHE-RSA-CHACHA20-POLY1305 */ 50 0x00, 0x9c, /* AES128-GCM-SHA256 */ 51 0x00, 0x3d, /* AES256-SHA256 */ 52 }; 53 54 static uint16_t cipher_values[] = { 55 0xcca8, /* ECDHE-ECDSA-CHACHA20-POLY1305 */ 56 0xcca9, /* ECDHE-RSA-CHACHA20-POLY1305 */ 57 0xccaa, /* DHE-RSA-CHACHA20-POLY1305 */ 58 0x009c, /* AES128-GCM-SHA256 */ 59 0x003d, /* AES256-SHA256 */ 60 }; 61 62 #define N_CIPHERS (sizeof(cipher_bytes) / 2) 63 64 static int 65 ssl_bytes_to_list_alloc(SSL *s, STACK_OF(SSL_CIPHER) **ciphers) 66 { 67 SSL_CIPHER *cipher; 68 uint16_t value; 69 CBS cbs; 70 int i; 71 72 CBS_init(&cbs, cipher_bytes, sizeof(cipher_bytes)); 73 74 *ciphers = ssl_bytes_to_cipher_list(s, &cbs); 75 CHECK(*ciphers != NULL); 76 CHECK(sk_SSL_CIPHER_num(*ciphers) == N_CIPHERS); 77 for (i = 0; i < sk_SSL_CIPHER_num(*ciphers); i++) { 78 cipher = sk_SSL_CIPHER_value(*ciphers, i); 79 CHECK(cipher != NULL); 80 value = SSL_CIPHER_get_value(cipher); 81 CHECK(value == cipher_values[i]); 82 } 83 84 return 1; 85 } 86 87 static int 88 ssl_list_to_bytes_scsv(SSL *s, STACK_OF(SSL_CIPHER) **ciphers) 89 { 90 CBB cbb; 91 unsigned char *buf = NULL; 92 size_t buflen, outlen; 93 int ret = 0; 94 95 /* Space for cipher bytes, plus reneg SCSV and two spare bytes. */ 96 CHECK(sk_SSL_CIPHER_num(*ciphers) == N_CIPHERS); 97 buflen = sizeof(cipher_bytes) + 2 + 2; 98 CHECK((buf = calloc(1, buflen)) != NULL); 99 100 CHECK(CBB_init_fixed(&cbb, buf, buflen)); 101 CHECK(ssl_cipher_list_to_bytes(s, *ciphers, &cbb)); 102 CHECK(CBB_finish(&cbb, NULL, &outlen)); 103 104 CHECK_GOTO(outlen > 0 && outlen == buflen - 2); 105 CHECK_GOTO(memcmp(buf, cipher_bytes, sizeof(cipher_bytes)) == 0); 106 CHECK_GOTO(buf[buflen - 4] == 0x00 && buf[buflen - 3] == 0xff); 107 CHECK_GOTO(buf[buflen - 2] == 0x00 && buf[buflen - 1] == 0x00); 108 109 ret = 1; 110 111 err: 112 free(buf); 113 return ret; 114 } 115 116 static int 117 ssl_list_to_bytes_no_scsv(SSL *s, STACK_OF(SSL_CIPHER) **ciphers) 118 { 119 CBB cbb; 120 unsigned char *buf = NULL; 121 size_t buflen, outlen; 122 int ret = 0; 123 124 /* Space for cipher bytes and two spare bytes */ 125 CHECK(sk_SSL_CIPHER_num(*ciphers) == N_CIPHERS); 126 buflen = sizeof(cipher_bytes) + 2; 127 CHECK((buf = calloc(1, buflen)) != NULL); 128 buf[buflen - 2] = 0xfe; 129 buf[buflen - 1] = 0xab; 130 131 /* Set renegotiate so it doesn't add SCSV */ 132 s->internal->renegotiate = 1; 133 134 CHECK(CBB_init_fixed(&cbb, buf, buflen)); 135 CHECK(ssl_cipher_list_to_bytes(s, *ciphers, &cbb)); 136 CHECK(CBB_finish(&cbb, NULL, &outlen)); 137 138 CHECK_GOTO(outlen > 0 && outlen == buflen - 2); 139 CHECK_GOTO(memcmp(buf, cipher_bytes, sizeof(cipher_bytes)) == 0); 140 CHECK_GOTO(buf[buflen - 2] == 0xfe && buf[buflen - 1] == 0xab); 141 142 ret = 1; 143 144 err: 145 free(buf); 146 return ret; 147 } 148 149 static int 150 ssl_bytes_to_list_invalid(SSL *s, STACK_OF(SSL_CIPHER) **ciphers) 151 { 152 uint8_t empty_cipher_bytes[] = {0}; 153 CBS cbs; 154 155 sk_SSL_CIPHER_free(*ciphers); 156 157 /* Invalid length: CipherSuite is 2 bytes so it must be even */ 158 CBS_init(&cbs, cipher_bytes, sizeof(cipher_bytes) - 1); 159 *ciphers = ssl_bytes_to_cipher_list(s, &cbs); 160 CHECK(*ciphers == NULL); 161 162 /* Invalid length: cipher_suites must be at least 2 */ 163 CBS_init(&cbs, empty_cipher_bytes, sizeof(empty_cipher_bytes)); 164 *ciphers = ssl_bytes_to_cipher_list(s, &cbs); 165 CHECK(*ciphers == NULL); 166 167 return 1; 168 } 169 170 int 171 main(void) 172 { 173 STACK_OF(SSL_CIPHER) *ciphers = NULL; 174 SSL_CTX *ctx = NULL; 175 SSL *s = NULL; 176 int rv = 1; 177 178 SSL_library_init(); 179 180 /* Use TLSv1.2 client to get all ciphers. */ 181 CHECK_GOTO((ctx = SSL_CTX_new(TLSv1_2_client_method())) != NULL); 182 CHECK_GOTO((s = SSL_new(ctx)) != NULL); 183 184 if (!ssl_bytes_to_list_alloc(s, &ciphers)) 185 goto err; 186 if (!ssl_list_to_bytes_scsv(s, &ciphers)) 187 goto err; 188 if (!ssl_list_to_bytes_no_scsv(s, &ciphers)) 189 goto err; 190 if (!ssl_bytes_to_list_invalid(s, &ciphers)) 191 goto err; 192 193 rv = 0; 194 195 err: 196 sk_SSL_CIPHER_free(ciphers); 197 SSL_CTX_free(ctx); 198 SSL_free(s); 199 200 if (!rv) 201 printf("PASS %s\n", __FILE__); 202 203 return rv; 204 } 205