1 /* $NetBSD: print-ah.c,v 1.4 1996/05/20 00:41:16 fvdl Exp $ */
4 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that: (1) source code distributions
9 * retain the above copyright notice and this paragraph in its entirety, (2)
10 * distributions including binary code include the above copyright notice and
11 * this paragraph in its entirety in the documentation or other materials
12 * provided with the distribution, and (3) all advertising materials mentioning
13 * features or use of this software display the following acknowledgement:
14 * ``This product includes software developed by the University of California,
15 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16 * the University nor the names of its contributors may be used to endorse
17 * or promote products derived from this software without specific prior
19 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
24 /* \summary: IPSEC Encapsulating Security Payload (ESP) printer */
30 #include "netdissect-stdinc.h"
35 /* Any code in this file that depends on HAVE_LIBCRYPTO depends on
36 * HAVE_OPENSSL_EVP_H too. Undefining the former when the latter isn't defined
37 * is the simplest way of handling the dependency.
40 #ifdef HAVE_OPENSSL_EVP_H
41 #include <openssl/evp.h>
47 #include "netdissect.h"
51 #include "strtoaddr.h"
52 #include "ascii_strcasecmp.h"
59 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
60 * All rights reserved.
62 * Redistribution and use in source and binary forms, with or without
63 * modification, are permitted provided that the following conditions
65 * 1. Redistributions of source code must retain the above copyright
66 * notice, this list of conditions and the following disclaimer.
67 * 2. Redistributions in binary form must reproduce the above copyright
68 * notice, this list of conditions and the following disclaimer in the
69 * documentation and/or other materials provided with the distribution.
70 * 3. Neither the name of the project nor the names of its contributors
71 * may be used to endorse or promote products derived from this software
72 * without specific prior written permission.
74 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
75 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
76 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
77 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
78 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
79 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
80 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
81 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
82 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
83 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
88 * RFC1827/2406 Encapsulated Security Payload.
92 nd_uint32_t esp_spi; /* ESP */
93 nd_uint32_t esp_seq; /* Sequence number */
94 /*variable size*/ /* (IV and) Payload data */
95 /*variable size*/ /* padding */
96 /*8bit*/ /* pad size */
97 /*8bit*/ /* next header */
98 /*8bit*/ /* next header */
99 /*variable size, 32bit bound*/ /* Authentication data */
102 #ifdef HAVE_LIBCRYPTO
108 struct sa_list *next;
110 union inaddr_u daddr;
111 uint32_t spi; /* if == 0, then IKEv2 */
113 u_char spii[8]; /* for IKEv2 */
115 const EVP_CIPHER *evp;
118 u_char authsecret[256];
120 u_char secret[256]; /* is that big enough for all secrets? */
124 #ifndef HAVE_EVP_CIPHER_CTX_NEW
126 * Allocate an EVP_CIPHER_CTX.
127 * Used if we have an older version of OpenSSL that doesn't provide
128 * routines to allocate and free them.
130 static EVP_CIPHER_CTX *
131 EVP_CIPHER_CTX_new(void)
135 ctx = malloc(sizeof(*ctx));
138 memset(ctx, 0, sizeof(*ctx));
143 EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
145 EVP_CIPHER_CTX_cleanup(ctx);
150 #ifdef HAVE_EVP_DECRYPTINIT_EX
152 * Initialize the cipher by calling EVP_DecryptInit_ex(), because
153 * calling EVP_DecryptInit() will reset the cipher context, clearing
154 * the cipher, so calling it twice, with the second call having a
155 * null cipher, will clear the already-set cipher. EVP_DecryptInit_ex(),
156 * however, won't reset the cipher context, so you can use it to specify
157 * the IV in a second call after a first call to EVP_DecryptInit_ex()
158 * to set the cipher and the key.
160 * XXX - is there some reason why we need to make two calls?
163 set_cipher_parameters(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
164 const unsigned char *key,
165 const unsigned char *iv)
167 return EVP_DecryptInit_ex(ctx, cipher, NULL, key, iv);
171 * Initialize the cipher by calling EVP_DecryptInit(), because we don't
172 * have EVP_DecryptInit_ex(); we rely on it not trashing the context.
175 set_cipher_parameters(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
176 const unsigned char *key,
177 const unsigned char *iv)
179 return EVP_DecryptInit(ctx, cipher, key, iv);
184 do_decrypt(netdissect_options *ndo, const char *caller, struct sa_list *sa,
185 const u_char *iv, const u_char *ct, unsigned int ctlen)
188 unsigned int block_size;
193 ctx = EVP_CIPHER_CTX_new();
196 * Failed to initialize the cipher context.
197 * From a look at the OpenSSL code, this appears to
198 * mean "couldn't allocate memory for the cipher context";
199 * note that we're not passing any parameters, so there's
200 * not much else it can mean.
202 (*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
203 "%s: can't allocate memory for cipher context", caller);
207 if (set_cipher_parameters(ctx, sa->evp, sa->secret, NULL) < 0) {
208 EVP_CIPHER_CTX_free(ctx);
209 (*ndo->ndo_warning)(ndo, "%s: espkey init failed", caller);
212 if (set_cipher_parameters(ctx, NULL, NULL, iv) < 0) {
213 EVP_CIPHER_CTX_free(ctx);
214 (*ndo->ndo_warning)(ndo, "%s: IV init failed", caller);
219 * At least as I read RFC 5996 section 3.14 and RFC 4303 section 2.4,
220 * if the cipher has a block size of which the ciphertext's size must
221 * be a multiple, the payload must be padded to make that happen, so
222 * the ciphertext length must be a multiple of the block size. Fail
223 * if that's not the case.
225 block_size = (unsigned int)EVP_CIPHER_CTX_block_size(ctx);
226 if ((ctlen % block_size) != 0) {
227 EVP_CIPHER_CTX_free(ctx);
228 (*ndo->ndo_warning)(ndo,
229 "%s: ciphertext size %u is not a multiple of the cipher block size %u",
230 caller, ctlen, block_size);
235 * Attempt to allocate a buffer for the decrypted data, because
236 * we can't decrypt on top of the input buffer.
239 pt = (u_char *)malloc(ptlen);
241 EVP_CIPHER_CTX_free(ctx);
242 (*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
243 "%s: can't allocate memory for decryption buffer", caller);
248 * The size of the ciphertext handed to us is a multiple of the
249 * cipher block size, so we don't need to worry about padding.
251 if (!EVP_CIPHER_CTX_set_padding(ctx, 0)) {
253 EVP_CIPHER_CTX_free(ctx);
254 (*ndo->ndo_warning)(ndo,
255 "%s: EVP_CIPHER_CTX_set_padding failed", caller);
258 if (!EVP_DecryptUpdate(ctx, pt, &len, ct, ctlen)) {
260 EVP_CIPHER_CTX_free(ctx);
261 (*ndo->ndo_warning)(ndo, "%s: EVP_DecryptUpdate failed",
265 EVP_CIPHER_CTX_free(ctx);
270 * This will allocate a new buffer containing the decrypted data.
271 * It returns 1 on success and 0 on failure.
273 * It will push the new buffer and the values of ndo->ndo_packetp and
274 * ndo->ndo_snapend onto the buffer stack, and change ndo->ndo_packetp
275 * and ndo->ndo_snapend to refer to the new buffer.
277 * Our caller must pop the buffer off the stack when it's finished
278 * dissecting anything in it and before it does any dissection of
279 * anything in the old buffer. That will free the new buffer.
281 USES_APPLE_DEPRECATED_API
282 int esp_decrypt_buffer_by_ikev2_print(netdissect_options *ndo,
284 const u_char spii[8],
285 const u_char spir[8],
286 const u_char *buf, const u_char *end)
294 /* initiator arg is any non-zero value */
295 if(initiator) initiator=1;
297 /* see if we can find the SA, and if so, decode it */
298 for (sa = ndo->ndo_sa_list_head; sa != NULL; sa = sa->next) {
300 && initiator == sa->initiator
301 && memcmp(spii, sa->spii, 8) == 0
302 && memcmp(spir, sa->spir, 8) == 0)
306 if(sa == NULL) return 0;
307 if(sa->evp == NULL) return 0;
310 * remove authenticator, and see if we still have something to
313 end = end - sa->authlen;
318 if(end <= ct) return 0;
320 pt = do_decrypt(ndo, "esp_decrypt_buffer_by_ikev2_print", sa, iv,
326 * Switch to the output buffer for dissection, and save it
327 * on the buffer stack so it can be freed; our caller must
330 if (!nd_push_buffer(ndo, pt, pt, pt + ctlen)) {
339 static void esp_print_addsa(netdissect_options *ndo,
340 struct sa_list *sa, int sa_def)
346 /* malloc() return used in a 'struct sa_list': do not free() */
347 nsa = (struct sa_list *)malloc(sizeof(struct sa_list));
349 (*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
350 "%s: malloc", __func__);
355 ndo->ndo_sa_default = nsa;
357 nsa->next = ndo->ndo_sa_list_head;
358 ndo->ndo_sa_list_head = nsa;
362 static u_int hexdigit(netdissect_options *ndo, char hex)
364 if (hex >= '0' && hex <= '9')
366 else if (hex >= 'A' && hex <= 'F')
367 return (hex - 'A' + 10);
368 else if (hex >= 'a' && hex <= 'f')
369 return (hex - 'a' + 10);
371 (*ndo->ndo_error)(ndo, S_ERR_ND_ESP_SECRET,
372 "invalid hex digit %c in espsecret\n", hex);
376 static u_int hex2byte(netdissect_options *ndo, char *hexstring)
380 byte = (hexdigit(ndo, hexstring[0]) << 4) + hexdigit(ndo, hexstring[1]);
385 * returns size of binary, 0 on failure.
388 int espprint_decode_hex(netdissect_options *ndo,
389 u_char *binbuf, unsigned int binbuf_len,
395 len = strlen(hex) / 2;
397 if (len > binbuf_len) {
398 (*ndo->ndo_warning)(ndo, "secret is too big: %u\n", len);
403 while (hex[0] != '\0' && hex[1]!='\0') {
404 binbuf[i] = hex2byte(ndo, hex);
413 * decode the form: SPINUM@IP <tab> ALGONAME:0xsecret
416 USES_APPLE_DEPRECATED_API
418 espprint_decode_encalgo(netdissect_options *ndo,
419 char *decode, struct sa_list *sa)
422 const EVP_CIPHER *evp;
426 colon = strchr(decode, ':');
428 (*ndo->ndo_warning)(ndo, "failed to decode espsecret: %s\n", decode);
433 if (strlen(decode) > strlen("-hmac96") &&
434 !strcmp(decode + strlen(decode) - strlen("-hmac96"),
436 p = strstr(decode, "-hmac96");
440 if (strlen(decode) > strlen("-cbc") &&
441 !strcmp(decode + strlen(decode) - strlen("-cbc"), "-cbc")) {
442 p = strstr(decode, "-cbc");
445 evp = EVP_get_cipherbyname(decode);
448 (*ndo->ndo_warning)(ndo, "failed to find cipher algo %s\n", decode);
456 sa->authlen = authlen;
457 /* This returns an int, but it should never be negative */
458 sa->ivlen = EVP_CIPHER_iv_length(evp);
461 if (colon[0] == '0' && colon[1] == 'x') {
462 /* decode some hex! */
465 sa->secretlen = espprint_decode_hex(ndo, sa->secret, sizeof(sa->secret), colon);
466 if(sa->secretlen == 0) return 0;
470 if (i < sizeof(sa->secret)) {
471 memcpy(sa->secret, colon, i);
474 memcpy(sa->secret, colon, sizeof(sa->secret));
475 sa->secretlen = sizeof(sa->secret);
484 * for the moment, ignore the auth algorithm, just hard code the authenticator
485 * length. Need to research how openssl looks up HMAC stuff.
488 espprint_decode_authalgo(netdissect_options *ndo,
489 char *decode, struct sa_list *sa)
493 colon = strchr(decode, ':');
495 (*ndo->ndo_warning)(ndo, "failed to decode espsecret: %s\n", decode);
500 if(ascii_strcasecmp(decode,"sha1") == 0 ||
501 ascii_strcasecmp(decode,"md5") == 0) {
507 static void esp_print_decode_ikeline(netdissect_options *ndo, char *line,
508 const char *file, int lineno)
510 /* it's an IKEv2 secret, store it instead */
514 char *icookie, *rcookie;
519 init = strsep(&line, " \t");
520 icookie = strsep(&line, " \t");
521 rcookie = strsep(&line, " \t");
522 authkey = strsep(&line, " \t");
523 enckey = strsep(&line, " \t");
525 /* if any fields are missing */
526 if(!init || !icookie || !rcookie || !authkey || !enckey) {
527 (*ndo->ndo_warning)(ndo, "print_esp: failed to find all fields for ikev2 at %s:%u",
533 ilen = strlen(icookie);
534 rlen = strlen(rcookie);
536 if((init[0]!='I' && init[0]!='R')
537 || icookie[0]!='0' || icookie[1]!='x'
538 || rcookie[0]!='0' || rcookie[1]!='x'
541 (*ndo->ndo_warning)(ndo, "print_esp: line %s:%u improperly formatted.",
544 (*ndo->ndo_warning)(ndo, "init=%s icookie=%s(%u) rcookie=%s(%u)",
545 init, icookie, ilen, rcookie, rlen);
551 sa1.initiator = (init[0] == 'I');
552 if(espprint_decode_hex(ndo, sa1.spii, sizeof(sa1.spii), icookie+2)!=8)
555 if(espprint_decode_hex(ndo, sa1.spir, sizeof(sa1.spir), rcookie+2)!=8)
558 if(!espprint_decode_encalgo(ndo, enckey, &sa1)) return;
560 if(!espprint_decode_authalgo(ndo, authkey, &sa1)) return;
562 esp_print_addsa(ndo, &sa1, FALSE);
567 * special form: file /name
568 * causes us to go read from this file instead.
571 static void esp_print_decode_onesecret(netdissect_options *ndo, char *line,
572 const char *file, int lineno)
580 spikey = strsep(&line, " \t");
582 memset(&sa1, 0, sizeof(struct sa_list));
584 /* if there is only one token, then it is an algo:key token */
588 /* sa1.daddr.version = 0; */
589 /* memset(&sa1.daddr, 0, sizeof(sa1.daddr)); */
595 if (spikey && ascii_strcasecmp(spikey, "file") == 0) {
596 /* open file and read it */
599 int subfile_lineno=0;
601 char *filename = line;
603 secretfile = fopen(filename, FOPEN_READ_TXT);
604 if (secretfile == NULL) {
605 (*ndo->ndo_error)(ndo, S_ERR_ND_OPEN_FILE,
606 "%s: can't open %s: %s\n",
607 __func__, filename, strerror(errno));
610 while (fgets(fileline, sizeof(fileline)-1, secretfile) != NULL) {
612 /* remove newline from the line */
613 nl = strchr(fileline, '\n');
616 if (fileline[0] == '#') continue;
617 if (fileline[0] == '\0') continue;
619 esp_print_decode_onesecret(ndo, fileline, filename, subfile_lineno);
626 if (spikey && ascii_strcasecmp(spikey, "ikev2") == 0) {
627 esp_print_decode_ikeline(ndo, line, file, lineno);
636 spistr = strsep(&spikey, "@");
637 if (spistr == NULL) {
638 (*ndo->ndo_warning)(ndo, "print_esp: failed to find the @ token");
642 spino = strtoul(spistr, &foo, 0);
643 if (spistr == foo || !spikey) {
644 (*ndo->ndo_warning)(ndo, "print_esp: failed to decode spi# %s\n", foo);
650 if (strtoaddr6(spikey, &sa1.daddr.in6) == 1) {
651 sa1.daddr_version = 6;
652 } else if (strtoaddr(spikey, &sa1.daddr.in4) == 1) {
653 sa1.daddr_version = 4;
655 (*ndo->ndo_warning)(ndo, "print_esp: can not decode IP# %s\n", spikey);
661 /* skip any blank spaces */
662 while (*decode == ' ' || *decode == '\t' || *decode == '\r' || *decode == '\n')
665 if(!espprint_decode_encalgo(ndo, decode, &sa1)) {
670 esp_print_addsa(ndo, &sa1, sa_def);
673 USES_APPLE_DEPRECATED_API
674 static void esp_init(netdissect_options *ndo _U_)
677 * 0.9.6 doesn't appear to define OPENSSL_API_COMPAT, so
678 * we check whether it's undefined or it's less than the
681 #if !defined(OPENSSL_API_COMPAT) || OPENSSL_API_COMPAT < 0x10100000L
682 OpenSSL_add_all_algorithms();
684 EVP_add_cipher_alias(SN_des_ede3_cbc, "3des");
688 void esp_decodesecret_print(netdissect_options *ndo)
692 static int initialized = 0;
699 p = ndo->ndo_espsecret;
701 while (p && p[0] != '\0') {
702 /* pick out the first line or first thing until a comma */
703 if ((line = strsep(&p, "\n,")) == NULL) {
708 esp_print_decode_onesecret(ndo, line, "cmdline", 0);
711 ndo->ndo_espsecret = NULL;
716 #ifdef HAVE_LIBCRYPTO
717 #define USED_IF_LIBCRYPTO
719 #define USED_IF_LIBCRYPTO _U_
722 #ifdef HAVE_LIBCRYPTO
723 USES_APPLE_DEPRECATED_API
726 esp_print(netdissect_options *ndo,
727 const u_char *bp, u_int length,
728 const u_char *bp2 USED_IF_LIBCRYPTO,
729 u_int ver USED_IF_LIBCRYPTO,
730 int fragmented USED_IF_LIBCRYPTO,
731 u_int ttl_hl USED_IF_LIBCRYPTO)
733 const struct newesp *esp;
735 #ifdef HAVE_LIBCRYPTO
737 struct sa_list *sa = NULL;
738 const struct ip6_hdr *ip6 = NULL;
748 ndo->ndo_protocol = "esp";
749 esp = (const struct newesp *)bp;
751 /* 'ep' points to the end of available data. */
752 ep = ndo->ndo_snapend;
754 if ((const u_char *)(esp + 1) >= ep) {
758 ND_PRINT("ESP(spi=0x%08x", GET_BE_U_4(esp->esp_spi));
759 ND_PRINT(",seq=0x%x)", GET_BE_U_4(esp->esp_seq));
760 ND_PRINT(", length %u", length);
762 #ifdef HAVE_LIBCRYPTO
763 /* initiailize SAs */
764 if (ndo->ndo_sa_list_head == NULL) {
765 if (!ndo->ndo_espsecret)
768 esp_decodesecret_print(ndo);
771 if (ndo->ndo_sa_list_head == NULL)
774 ip = (const struct ip *)bp2;
777 ip6 = (const struct ip6_hdr *)bp2;
778 /* we do not attempt to decrypt jumbograms */
779 if (!GET_BE_U_2(ip6->ip6_plen))
781 /* XXX - check whether it's fragmented? */
782 /* if we can't get nexthdr, we do not need to decrypt it */
784 /* see if we can find the SA, and if so, decode it */
785 for (sa = ndo->ndo_sa_list_head; sa != NULL; sa = sa->next) {
786 if (sa->spi == GET_BE_U_4(esp->esp_spi) &&
787 sa->daddr_version == 6 &&
788 UNALIGNED_MEMCMP(&sa->daddr.in6, &ip6->ip6_dst,
789 sizeof(nd_ipv6)) == 0) {
795 /* nexthdr & padding are in the last fragment */
799 /* see if we can find the SA, and if so, decode it */
800 for (sa = ndo->ndo_sa_list_head; sa != NULL; sa = sa->next) {
801 if (sa->spi == GET_BE_U_4(esp->esp_spi) &&
802 sa->daddr_version == 4 &&
803 UNALIGNED_MEMCMP(&sa->daddr.in4, &ip->ip_dst,
804 sizeof(nd_ipv4)) == 0) {
813 /* if we didn't find the specific one, then look for
814 * an unspecified one.
817 sa = ndo->ndo_sa_default;
819 /* if not found fail */
823 /* pointer to the IV, if there is one */
824 iv = (const u_char *)(esp + 1) + 0;
825 /* length of the IV, if there is one; 0, if there isn't */
829 * Get a pointer to the ciphertext.
831 * p points to the beginning of the payload, i.e. to the
832 * initialization vector, so if we skip past the initialization
833 * vector, it points to the beginning of the ciphertext.
838 * Make sure the authentication data/integrity check value length
839 * isn't bigger than the total amount of data available after
840 * the ESP header and initialization vector is removed and,
841 * if not, slice the authentication data/ICV off.
843 if (ep - ct < sa->authlen) {
847 ep = ep - sa->authlen;
850 * Calculate the length of the ciphertext. ep points to
851 * the beginning of the authentication data/integrity check
852 * value, i.e. right past the end of the ciphertext;
854 payloadlen = ep - ct;
860 * If the next header value is past the end of the available
861 * data, we won't be able to fetch it once we've decrypted
862 * the ciphertext, so there's no point in decrypting the data.
864 * Report it as truncation.
866 if (!ND_TTEST_1(ep - 1)) {
871 pt = do_decrypt(ndo, "esp_print", sa, iv, ct, payloadlen);
876 * Switch to the output buffer for dissection, and
877 * save it on the buffer stack so it can be freed.
879 ep = pt + payloadlen;
880 if (!nd_push_buffer(ndo, pt, pt, ep)) {
882 (*ndo->ndo_error)(ndo, S_ERR_ND_MEM_ALLOC,
883 "%s: can't push buffer on buffer stack", __func__);
887 * Sanity check for pad length; if it, plus 2 for the pad
888 * length and next header fields, is bigger than the ciphertext
889 * length (which is also the plaintext length), it's too big.
891 * XXX - the check can fail if the packet is corrupt *or* if
892 * it was not decrypted with the correct key, so that the
893 * "plaintext" is not what was being sent.
895 padlen = GET_U_1(ep - 2);
896 if (padlen + 2 > payloadlen) {
901 /* Get the next header */
902 nh = GET_U_1(ep - 1);
907 * Don't put padding + padding length(1 byte) + next header(1 byte)
908 * in the buffer because they are not part of the plaintext to decode.
910 nd_push_snapend(ndo, ep - (padlen + 2));
912 /* Now dissect the plaintext. */
913 ip_demux_print(ndo, pt, payloadlen - (padlen + 2), ver, fragmented,
916 /* Pop the buffer, freeing it. */
917 nd_pop_packet_info(ndo);
918 /* Pop the nd_push_snapend */
919 nd_pop_packet_info(ndo);
922 #ifdef HAVE_LIBCRYPTO