* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
-#ifndef lint
-static const char rcsid[] =
- "@(#) $Header: /tcpdump/master/tcpdump/print-esp.c,v 1.24 2002-04-07 02:16:03 guy Exp $ (LBL)";
-#endif
+/* \summary: IPSEC Encapsulating Security Payload (ESP) printer */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
+#include <netdissect-stdinc.h>
+
#include <string.h>
-#include <sys/param.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/socket.h>
#include <stdlib.h>
-#include <netinet/in.h>
-
+/* Any code in this file that depends on HAVE_LIBCRYPTO depends on
+ * HAVE_OPENSSL_EVP_H too. Undefining the former when the latter isn't defined
+ * is the simplest way of handling the dependency.
+ */
#ifdef HAVE_LIBCRYPTO
-#include <openssl/des.h>
-#include <openssl/blowfish.h>
-#ifdef HAVE_OPENSSL_RC5_H
-#include <openssl/rc5.h>
-#endif
-#ifdef HAVE_OPENSSL_CAST_H
-#include <openssl/cast.h>
+#ifdef HAVE_OPENSSL_EVP_H
+#include <openssl/evp.h>
+#else
+#undef HAVE_LIBCRYPTO
#endif
#endif
-#include <stdio.h>
+#include "netdissect.h"
+#include "strtoaddr.h"
+#include "extract.h"
+
+#include "ascii_strcasecmp.h"
#include "ip.h"
-#include "esp.h"
-#ifdef INET6
#include "ip6.h"
+
+/*
+ * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the project nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * RFC1827/2406 Encapsulated Security Payload.
+ */
+
+struct newesp {
+ uint32_t esp_spi; /* ESP */
+ uint32_t esp_seq; /* Sequence number */
+ /*variable size*/ /* (IV and) Payload data */
+ /*variable size*/ /* padding */
+ /*8bit*/ /* pad size */
+ /*8bit*/ /* next header */
+ /*8bit*/ /* next header */
+ /*variable size, 32bit bound*/ /* Authentication data */
+};
+
+#ifdef HAVE_LIBCRYPTO
+union inaddr_u {
+ struct in_addr in4;
+ struct in6_addr in6;
+};
+struct sa_list {
+ struct sa_list *next;
+ u_int daddr_version;
+ union inaddr_u daddr;
+ uint32_t spi; /* if == 0, then IKEv2 */
+ int initiator;
+ u_char spii[8]; /* for IKEv2 */
+ u_char spir[8];
+ const EVP_CIPHER *evp;
+ int ivlen;
+ int authlen;
+ u_char authsecret[256];
+ int authsecret_len;
+ u_char secret[256]; /* is that big enough for all secrets? */
+ int secretlen;
+};
+
+#ifndef HAVE_EVP_CIPHER_CTX_NEW
+/*
+ * Allocate an EVP_CIPHER_CTX.
+ * Used if we have an older version of OpenSSL that doesn't provide
+ * routines to allocate and free them.
+ */
+static EVP_CIPHER_CTX *
+EVP_CIPHER_CTX_new(void)
+{
+ EVP_CIPHER_CTX *ctx;
+
+ ctx = malloc(sizeof(*ctx));
+ if (ctx == NULL)
+ return (NULL);
+ memset(ctx, 0, sizeof(*ctx));
+ return (ctx);
+}
+
+static void
+EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
+{
+ EVP_CIPHER_CTX_cleanup(ctx);
+ free(ctx);
+}
#endif
-#define AVOID_CHURN 1
-#include "interface.h"
-#include "addrtoname.h"
+#ifdef HAVE_EVP_CIPHERINIT_EX
+/*
+ * Initialize the cipher by calling EVP_CipherInit_ex(), because
+ * calling EVP_CipherInit() will reset the cipher context, clearing
+ * the cipher, so calling it twice, with the second call having a
+ * null cipher, will clear the already-set cipher. EVP_CipherInit_ex(),
+ * however, won't reset the cipher context, so you can use it to specify
+ * the IV oin a second call after a first call to EVP_CipherInit_ex()
+ * to set the cipher and the key.
+ *
+ * XXX - is there some reason why we need to make two calls?
+ */
+static int
+set_cipher_parameters(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
+ const unsigned char *key,
+ const unsigned char *iv, int enc)
+{
+ return EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, enc);
+}
+#else
+/*
+ * Initialize the cipher by calling EVP_CipherInit(), because we don't
+ * have EVP_CipherInit_ex(); we rely on it not trashing the context.
+ */
+static int
+set_cipher_parameters(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
+ const unsigned char *key,
+ const unsigned char *iv, int enc)
+{
+ return EVP_CipherInit(ctx, cipher, key, iv, enc);
+}
+#endif
-static struct esp_algorithm *espsecret_xform=NULL; /* cache of decoded alg. */
-static char *espsecret_key=NULL;
+/*
+ * this will adjust ndo_packetp and ndo_snapend to new buffer!
+ */
+USES_APPLE_DEPRECATED_API
+int esp_print_decrypt_buffer_by_ikev2(netdissect_options *ndo,
+ int initiator,
+ u_char spii[8], u_char spir[8],
+ const u_char *buf, const u_char *end)
+{
+ struct sa_list *sa;
+ const u_char *iv;
+ unsigned int len;
+ EVP_CIPHER_CTX *ctx;
+ unsigned int block_size, buffer_size;
+ u_char *input_buffer, *output_buffer;
+
+ /* initiator arg is any non-zero value */
+ if(initiator) initiator=1;
+
+ /* see if we can find the SA, and if so, decode it */
+ for (sa = ndo->ndo_sa_list_head; sa != NULL; sa = sa->next) {
+ if (sa->spi == 0
+ && initiator == sa->initiator
+ && memcmp(spii, sa->spii, 8) == 0
+ && memcmp(spir, sa->spir, 8) == 0)
+ break;
+ }
+ if(sa == NULL) return 0;
+ if(sa->evp == NULL) return 0;
-enum cipher { NONE,
- DESCBC,
- BLOWFISH,
- RC5,
- CAST128,
- DES3CBC};
+ /*
+ * remove authenticator, and see if we still have something to
+ * work with
+ */
+ end = end - sa->authlen;
+ iv = buf;
+ buf = buf + sa->ivlen;
+ len = end-buf;
+ if(end <= buf) return 0;
+ ctx = EVP_CIPHER_CTX_new();
+ if (ctx == NULL)
+ return 0;
+ if (set_cipher_parameters(ctx, sa->evp, sa->secret, NULL, 0) < 0)
+ (*ndo->ndo_warning)(ndo, "espkey init failed");
+ set_cipher_parameters(ctx, NULL, NULL, iv, 0);
+ /*
+ * Allocate buffers for the encrypted and decrypted data.
+ * Both buffers' sizes must be a multiple of the cipher block
+ * size, and the output buffer must be separate from the input
+ * buffer.
+ */
+ block_size = (unsigned int)EVP_CIPHER_CTX_block_size(ctx);
+ buffer_size = len + (block_size - len % block_size);
+
+ /*
+ * Attempt to allocate the input buffer.
+ */
+ input_buffer = (u_char *)malloc(buffer_size);
+ if (input_buffer == NULL) {
+ EVP_CIPHER_CTX_free(ctx);
+ (*ndo->ndo_error)(ndo, "can't allocate memory for encrypted data buffer");
+ }
+ /*
+ * Copy the input data to the encrypted data buffer, and pad it
+ * with zeroes.
+ */
+ memcpy(input_buffer, buf, len);
+ memset(input_buffer + len, 0, buffer_size - len);
+
+ /*
+ * Attempt to allocate the output buffer.
+ */
+ output_buffer = (u_char *)malloc(buffer_size);
+ if (output_buffer == NULL) {
+ free(input_buffer);
+ EVP_CIPHER_CTX_free(ctx);
+ (*ndo->ndo_error)(ndo, "can't allocate memory for decryption buffer");
+ }
+ EVP_Cipher(ctx, output_buffer, input_buffer, len);
+ EVP_CIPHER_CTX_free(ctx);
-struct esp_algorithm {
- char *name;
- enum cipher algo;
- int ivlen;
- int authlen;
- int replaysize;
-};
+ /*
+ * XXX - of course this is wrong, because buf is a const buffer,
+ * but changing this would require a more complicated fix.
+ */
+ memcpy(buf, output_buffer, len);
+ free(input_buffer);
+ free(output_buffer);
-struct esp_algorithm esp_xforms[]={
- {"none", NONE, 0, 0, 0},
- {"des-cbc", DESCBC, 8, 0, 0},
- {"des-cbc-hmac96", DESCBC, 8, 12, 4},
- {"blowfish-cbc", BLOWFISH,8, 0, 0},
- {"blowfish-cbc-hmac96", BLOWFISH,8, 12, 4},
- {"rc5-cbc", RC5, 8, 0, 0},
- {"rc5-cbc-hmac96", RC5, 8, 12, 4},
- {"cast128-cbc", CAST128, 8, 0, 0},
- {"cast128-cbc-hmac96", CAST128, 8, 12, 4},
- {"3des-cbc-hmac96", DES3CBC, 8, 12, 4},
-};
+ ndo->ndo_packetp = buf;
+ ndo->ndo_snapend = end;
+
+ return 1;
+}
+USES_APPLE_RST
+
+static void esp_print_addsa(netdissect_options *ndo,
+ struct sa_list *sa, int sa_def)
+{
+ /* copy the "sa" */
+
+ struct sa_list *nsa;
+
+ nsa = (struct sa_list *)malloc(sizeof(struct sa_list));
+ if (nsa == NULL)
+ (*ndo->ndo_error)(ndo, "ran out of memory to allocate sa structure");
-static int hexdigit(char hex)
+ *nsa = *sa;
+
+ if (sa_def)
+ ndo->ndo_sa_default = nsa;
+
+ nsa->next = ndo->ndo_sa_list_head;
+ ndo->ndo_sa_list_head = nsa;
+}
+
+
+static u_int hexdigit(netdissect_options *ndo, char hex)
{
- if(hex >= '0' && hex <= '9') {
+ if (hex >= '0' && hex <= '9')
return (hex - '0');
- } else if(hex >= 'A' && hex <= 'F') {
+ else if (hex >= 'A' && hex <= 'F')
return (hex - 'A' + 10);
- } else if(hex >= 'a' && hex <= 'f') {
+ else if (hex >= 'a' && hex <= 'f')
return (hex - 'a' + 10);
- } else {
- printf("invalid hex digit %c in espsecret\n", hex);
- return 0;
+ else {
+ (*ndo->ndo_error)(ndo, "invalid hex digit %c in espsecret\n", hex);
}
}
-static int hex2byte(char *hexstring)
+static u_int hex2byte(netdissect_options *ndo, char *hexstring)
{
- int byte;
+ u_int byte;
- byte = (hexdigit(hexstring[0]) << 4) +
- hexdigit(hexstring[1]);
+ byte = (hexdigit(ndo, hexstring[0]) << 4) + hexdigit(ndo, hexstring[1]);
return byte;
}
+/*
+ * returns size of binary, 0 on failure.
+ */
+static
+int espprint_decode_hex(netdissect_options *ndo,
+ u_char *binbuf, unsigned int binbuf_len,
+ char *hex)
+{
+ unsigned int len;
+ int i;
+
+ len = strlen(hex) / 2;
+
+ if (len > binbuf_len) {
+ (*ndo->ndo_warning)(ndo, "secret is too big: %d\n", len);
+ return 0;
+ }
+
+ i = 0;
+ while (hex[0] != '\0' && hex[1]!='\0') {
+ binbuf[i] = hex2byte(ndo, hex);
+ hex += 2;
+ i++;
+ }
+
+ return i;
+}
+
+/*
+ * decode the form: SPINUM@IP <tab> ALGONAME:0xsecret
+ */
+
+USES_APPLE_DEPRECATED_API
+static int
+espprint_decode_encalgo(netdissect_options *ndo,
+ char *decode, struct sa_list *sa)
+{
+ size_t i;
+ const EVP_CIPHER *evp;
+ int authlen = 0;
+ char *colon, *p;
+
+ colon = strchr(decode, ':');
+ if (colon == NULL) {
+ (*ndo->ndo_warning)(ndo, "failed to decode espsecret: %s\n", decode);
+ return 0;
+ }
+ *colon = '\0';
+
+ if (strlen(decode) > strlen("-hmac96") &&
+ !strcmp(decode + strlen(decode) - strlen("-hmac96"),
+ "-hmac96")) {
+ p = strstr(decode, "-hmac96");
+ *p = '\0';
+ authlen = 12;
+ }
+ if (strlen(decode) > strlen("-cbc") &&
+ !strcmp(decode + strlen(decode) - strlen("-cbc"), "-cbc")) {
+ p = strstr(decode, "-cbc");
+ *p = '\0';
+ }
+ evp = EVP_get_cipherbyname(decode);
+
+ if (!evp) {
+ (*ndo->ndo_warning)(ndo, "failed to find cipher algo %s\n", decode);
+ sa->evp = NULL;
+ sa->authlen = 0;
+ sa->ivlen = 0;
+ return 0;
+ }
+
+ sa->evp = evp;
+ sa->authlen = authlen;
+ sa->ivlen = EVP_CIPHER_iv_length(evp);
+
+ colon++;
+ if (colon[0] == '0' && colon[1] == 'x') {
+ /* decode some hex! */
-static void esp_print_decodesecret(void)
+ colon += 2;
+ sa->secretlen = espprint_decode_hex(ndo, sa->secret, sizeof(sa->secret), colon);
+ if(sa->secretlen == 0) return 0;
+ } else {
+ i = strlen(colon);
+
+ if (i < sizeof(sa->secret)) {
+ memcpy(sa->secret, colon, i);
+ sa->secretlen = i;
+ } else {
+ memcpy(sa->secret, colon, sizeof(sa->secret));
+ sa->secretlen = sizeof(sa->secret);
+ }
+ }
+
+ return 1;
+}
+USES_APPLE_RST
+
+/*
+ * for the moment, ignore the auth algorithm, just hard code the authenticator
+ * length. Need to research how openssl looks up HMAC stuff.
+ */
+static int
+espprint_decode_authalgo(netdissect_options *ndo,
+ char *decode, struct sa_list *sa)
{
char *colon;
- int len, i;
- struct esp_algorithm *xf;
- if(espsecret == NULL) {
- /* set to NONE transform */
- espsecret_xform = esp_xforms;
- return;
+ colon = strchr(decode, ':');
+ if (colon == NULL) {
+ (*ndo->ndo_warning)(ndo, "failed to decode espsecret: %s\n", decode);
+ return 0;
}
+ *colon = '\0';
+
+ if(ascii_strcasecmp(colon,"sha1") == 0 ||
+ ascii_strcasecmp(colon,"md5") == 0) {
+ sa->authlen = 12;
+ }
+ return 1;
+}
+
+static void esp_print_decode_ikeline(netdissect_options *ndo, char *line,
+ const char *file, int lineno)
+{
+ /* it's an IKEv2 secret, store it instead */
+ struct sa_list sa1;
+
+ char *init;
+ char *icookie, *rcookie;
+ int ilen, rlen;
+ char *authkey;
+ char *enckey;
+
+ init = strsep(&line, " \t");
+ icookie = strsep(&line, " \t");
+ rcookie = strsep(&line, " \t");
+ authkey = strsep(&line, " \t");
+ enckey = strsep(&line, " \t");
+
+ /* if any fields are missing */
+ if(!init || !icookie || !rcookie || !authkey || !enckey) {
+ (*ndo->ndo_warning)(ndo, "print_esp: failed to find all fields for ikev2 at %s:%u",
+ file, lineno);
- if(espsecret_key != NULL) {
return;
}
- colon = strchr(espsecret, ':');
- if(colon == NULL) {
- printf("failed to decode espsecret: %s\n",
- espsecret);
- /* set to NONE transform */
- espsecret_xform = esp_xforms;
+ ilen = strlen(icookie);
+ rlen = strlen(rcookie);
+
+ if((init[0]!='I' && init[0]!='R')
+ || icookie[0]!='0' || icookie[1]!='x'
+ || rcookie[0]!='0' || rcookie[1]!='x'
+ || ilen!=18
+ || rlen!=18) {
+ (*ndo->ndo_warning)(ndo, "print_esp: line %s:%u improperly formatted.",
+ file, lineno);
+
+ (*ndo->ndo_warning)(ndo, "init=%s icookie=%s(%u) rcookie=%s(%u)",
+ init, icookie, ilen, rcookie, rlen);
+
+ return;
}
- len = colon - espsecret;
- xf = esp_xforms;
- while(xf->name && strncasecmp(espsecret, xf->name, len)!=0) {
- xf++;
+ sa1.spi = 0;
+ sa1.initiator = (init[0] == 'I');
+ if(espprint_decode_hex(ndo, sa1.spii, sizeof(sa1.spii), icookie+2)!=8)
+ return;
+
+ if(espprint_decode_hex(ndo, sa1.spir, sizeof(sa1.spir), rcookie+2)!=8)
+ return;
+
+ if(!espprint_decode_encalgo(ndo, enckey, &sa1)) return;
+
+ if(!espprint_decode_authalgo(ndo, authkey, &sa1)) return;
+
+ esp_print_addsa(ndo, &sa1, FALSE);
+}
+
+/*
+ *
+ * special form: file /name
+ * causes us to go read from this file instead.
+ *
+ */
+static void esp_print_decode_onesecret(netdissect_options *ndo, char *line,
+ const char *file, int lineno)
+{
+ struct sa_list sa1;
+ int sa_def;
+
+ char *spikey;
+ char *decode;
+
+ spikey = strsep(&line, " \t");
+ sa_def = 0;
+ memset(&sa1, 0, sizeof(struct sa_list));
+
+ /* if there is only one token, then it is an algo:key token */
+ if (line == NULL) {
+ decode = spikey;
+ spikey = NULL;
+ /* sa1.daddr.version = 0; */
+ /* memset(&sa1.daddr, 0, sizeof(sa1.daddr)); */
+ /* sa1.spi = 0; */
+ sa_def = 1;
+ } else
+ decode = line;
+
+ if (spikey && ascii_strcasecmp(spikey, "file") == 0) {
+ /* open file and read it */
+ FILE *secretfile;
+ char fileline[1024];
+ int subfile_lineno=0;
+ char *nl;
+ char *filename = line;
+
+ secretfile = fopen(filename, FOPEN_READ_TXT);
+ if (secretfile == NULL) {
+ (*ndo->ndo_error)(ndo, "print_esp: can't open %s: %s\n",
+ filename, strerror(errno));
+ }
+
+ while (fgets(fileline, sizeof(fileline)-1, secretfile) != NULL) {
+ subfile_lineno++;
+ /* remove newline from the line */
+ nl = strchr(fileline, '\n');
+ if (nl)
+ *nl = '\0';
+ if (fileline[0] == '#') continue;
+ if (fileline[0] == '\0') continue;
+
+ esp_print_decode_onesecret(ndo, fileline, filename, subfile_lineno);
+ }
+ fclose(secretfile);
+
+ return;
}
- if(xf->name == NULL) {
- printf("failed to find cipher algo %s\n",
- espsecret);
- espsecret_xform = esp_xforms;
+
+ if (spikey && ascii_strcasecmp(spikey, "ikev2") == 0) {
+ esp_print_decode_ikeline(ndo, line, file, lineno);
return;
}
- espsecret_xform = xf;
- colon++;
- if(colon[0]=='0' && colon[1]=='x') {
- /* decode some hex! */
- colon+=2;
- len = strlen(colon) / 2;
- espsecret_key = (char *)malloc(len);
- if(espsecret_key == NULL) {
- fprintf(stderr, "%s: ran out of memory (%d) to allocate secret key\n",
- program_name, len);
- exit(2);
+ if (spikey) {
+
+ char *spistr, *foo;
+ uint32_t spino;
+
+ spistr = strsep(&spikey, "@");
+ if (spistr == NULL) {
+ (*ndo->ndo_warning)(ndo, "print_esp: failed to find the @ token");
+ return;
}
- i = 0;
- while(colon[0] != '\0' && colon[1]!='\0') {
- espsecret_key[i]=hex2byte(colon);
- colon+=2;
- i++;
+
+ spino = strtoul(spistr, &foo, 0);
+ if (spistr == foo || !spikey) {
+ (*ndo->ndo_warning)(ndo, "print_esp: failed to decode spi# %s\n", foo);
+ return;
}
- } else {
- espsecret_key = colon;
+
+ sa1.spi = spino;
+
+ if (strtoaddr6(spikey, &sa1.daddr.in6) == 1) {
+ sa1.daddr_version = 6;
+ } else if (strtoaddr(spikey, &sa1.daddr.in4) == 1) {
+ sa1.daddr_version = 4;
+ } else {
+ (*ndo->ndo_warning)(ndo, "print_esp: can not decode IP# %s\n", spikey);
+ return;
+ }
+ }
+
+ if (decode) {
+ /* skip any blank spaces */
+ while (isspace((unsigned char)*decode))
+ decode++;
+
+ if(!espprint_decode_encalgo(ndo, decode, &sa1)) {
+ return;
+ }
+ }
+
+ esp_print_addsa(ndo, &sa1, sa_def);
+}
+
+USES_APPLE_DEPRECATED_API
+static void esp_init(netdissect_options *ndo _U_)
+{
+ /*
+ * 0.9.6 doesn't appear to define OPENSSL_API_COMPAT, so
+ * we check whether it's undefined or it's less than the
+ * value for 1.1.0.
+ */
+#if !defined(OPENSSL_API_COMPAT) || OPENSSL_API_COMPAT < 0x10100000L
+ OpenSSL_add_all_algorithms();
+#endif
+ EVP_add_cipher_alias(SN_des_ede3_cbc, "3des");
+}
+USES_APPLE_RST
+
+void esp_print_decodesecret(netdissect_options *ndo)
+{
+ char *line;
+ char *p;
+ static int initialized = 0;
+
+ if (!initialized) {
+ esp_init(ndo);
+ initialized = 1;
}
+
+ p = ndo->ndo_espsecret;
+
+ while (p && p[0] != '\0') {
+ /* pick out the first line or first thing until a comma */
+ if ((line = strsep(&p, "\n,")) == NULL) {
+ line = p;
+ p = NULL;
+ }
+
+ esp_print_decode_onesecret(ndo, line, "cmdline", 0);
+ }
+
+ ndo->ndo_espsecret = NULL;
}
+#endif
+
+#ifdef HAVE_LIBCRYPTO
+USES_APPLE_DEPRECATED_API
+#endif
int
-esp_print(register const u_char *bp, register const u_char *bp2,
- int *nhdr, int *padlen)
+esp_print(netdissect_options *ndo,
+ const u_char *bp, const int length, const u_char *bp2
+#ifndef HAVE_LIBCRYPTO
+ _U_
+#endif
+ ,
+ int *nhdr
+#ifndef HAVE_LIBCRYPTO
+ _U_
+#endif
+ ,
+ int *padlen
+#ifndef HAVE_LIBCRYPTO
+ _U_
+#endif
+ )
{
- register const struct esp *esp;
+ register const struct newesp *esp;
register const u_char *ep;
- u_int32_t spi;
- struct ip *ip = NULL;
-#ifdef INET6
- struct ip6_hdr *ip6 = NULL;
-#endif
+#ifdef HAVE_LIBCRYPTO
+ const struct ip *ip;
+ struct sa_list *sa = NULL;
+ const struct ip6_hdr *ip6 = NULL;
int advance;
int len;
- char *secret;
+ u_char *secret;
int ivlen = 0;
- u_char *ivoff;
-#ifdef HAVE_LIBCRYPTO
- u_char *p;
+ const u_char *ivoff;
+ const u_char *p;
+ EVP_CIPHER_CTX *ctx;
+ unsigned int block_size, buffer_size;
+ u_char *input_buffer, *output_buffer;
#endif
-
- esp = (struct esp *)bp;
- spi = (u_int32_t)ntohl(esp->esp_spi);
+
+ esp = (const struct newesp *)bp;
+
+#ifdef HAVE_LIBCRYPTO
secret = NULL;
+ advance = 0;
+#endif
#if 0
/* keep secret out of a register */
#endif
/* 'ep' points to the end of available data. */
- ep = snapend;
+ ep = ndo->ndo_snapend;
- if ((u_char *)(esp + 1) >= ep - sizeof(struct esp)) {
- fputs("[|ESP]", stdout);
+ if ((const u_char *)(esp + 1) >= ep) {
+ ND_PRINT((ndo, "[|ESP]"));
goto fail;
}
- printf("ESP(spi=0x%08x", spi);
- printf(",seq=0x%x", (u_int32_t)ntohl(*(u_int32_t *)(esp + 1)));
- printf(")");
+ ND_PRINT((ndo, "ESP(spi=0x%08x", EXTRACT_32BITS(&esp->esp_spi)));
+ ND_PRINT((ndo, ",seq=0x%x)", EXTRACT_32BITS(&esp->esp_seq)));
+ ND_PRINT((ndo, ", length %u", length));
- /* if we don't have decryption key, we can't decrypt this packet. */
- if (!espsecret)
- goto fail;
+#ifndef HAVE_LIBCRYPTO
+ goto fail;
+#else
+ /* initiailize SAs */
+ if (ndo->ndo_sa_list_head == NULL) {
+ if (!ndo->ndo_espsecret)
+ goto fail;
- if(!espsecret_xform) {
- esp_print_decodesecret();
+ esp_print_decodesecret(ndo);
}
- if(espsecret_xform->algo == NONE) {
+
+ if (ndo->ndo_sa_list_head == NULL)
goto fail;
- }
- ip = (struct ip *)bp2;
+ ip = (const struct ip *)bp2;
switch (IP_V(ip)) {
-#ifdef INET6
case 6:
- ip6 = (struct ip6_hdr *)bp2;
- ip = NULL;
+ ip6 = (const struct ip6_hdr *)bp2;
/* we do not attempt to decrypt jumbograms */
- if (!ntohs(ip6->ip6_plen))
+ if (!EXTRACT_16BITS(&ip6->ip6_plen))
goto fail;
/* if we can't get nexthdr, we do not need to decrypt it */
- len = sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen);
+ len = sizeof(struct ip6_hdr) + EXTRACT_16BITS(&ip6->ip6_plen);
+
+ /* see if we can find the SA, and if so, decode it */
+ for (sa = ndo->ndo_sa_list_head; sa != NULL; sa = sa->next) {
+ if (sa->spi == EXTRACT_32BITS(&esp->esp_spi) &&
+ sa->daddr_version == 6 &&
+ UNALIGNED_MEMCMP(&sa->daddr.in6, &ip6->ip6_dst,
+ sizeof(struct in6_addr)) == 0) {
+ break;
+ }
+ }
break;
-#endif /*INET6*/
case 4:
/* nexthdr & padding are in the last fragment */
- if (ntohs(ip->ip_off) & IP_MF)
+ if (EXTRACT_16BITS(&ip->ip_off) & IP_MF)
goto fail;
-#ifdef INET6
- ip6 = NULL;
-#endif
- len = ntohs(ip->ip_len);
+ len = EXTRACT_16BITS(&ip->ip_len);
+
+ /* see if we can find the SA, and if so, decode it */
+ for (sa = ndo->ndo_sa_list_head; sa != NULL; sa = sa->next) {
+ if (sa->spi == EXTRACT_32BITS(&esp->esp_spi) &&
+ sa->daddr_version == 4 &&
+ UNALIGNED_MEMCMP(&sa->daddr.in4, &ip->ip_dst,
+ sizeof(struct in_addr)) == 0) {
+ break;
+ }
+ }
break;
default:
goto fail;
}
- /* if we can't get nexthdr, we do not need to decrypt it */
- if (ep - bp2 < len)
- goto fail;
-
- ivoff = (u_char *)(esp + 1) + espsecret_xform->replaysize;
- ivlen = espsecret_xform->ivlen;
- secret = espsecret_key;
-
- switch (espsecret_xform->algo) {
- case DESCBC:
-#ifdef HAVE_LIBCRYPTO
- {
- u_char iv[8];
- des_key_schedule schedule;
-
- switch (ivlen) {
- case 4:
- memcpy(iv, ivoff, 4);
- memcpy(&iv[4], ivoff, 4);
- p = &iv[4];
- *p++ ^= 0xff;
- *p++ ^= 0xff;
- *p++ ^= 0xff;
- *p++ ^= 0xff;
- break;
- case 8:
- memcpy(iv, ivoff, 8);
- break;
- default:
- goto fail;
- }
-
- des_check_key = 0;
- des_set_key((void *)secret, schedule);
-
- p = ivoff + ivlen;
- des_cbc_encrypt((void *)p, (void *)p,
- (long)(ep - p), schedule, (void *)iv,
- DES_DECRYPT);
- advance = ivoff - (u_char *)esp + ivlen;
- break;
- }
-#else
- goto fail;
-#endif /*HAVE_LIBCRYPTO*/
-
- case BLOWFISH:
-#ifdef HAVE_LIBCRYPTO
- {
- BF_KEY schedule;
-
- BF_set_key(&schedule, strlen(secret), secret);
-
- p = ivoff + ivlen;
- BF_cbc_encrypt(p, p, (long)(ep - p), &schedule, ivoff,
- BF_DECRYPT);
- advance = ivoff - (u_char *)esp + ivlen;
- break;
- }
-#else
- goto fail;
-#endif /*HAVE_LIBCRYPTO*/
-
- case RC5:
-#if defined(HAVE_LIBCRYPTO) && defined(HAVE_RC5_H)
- {
- RC5_32_KEY schedule;
+ /* if we didn't find the specific one, then look for
+ * an unspecified one.
+ */
+ if (sa == NULL)
+ sa = ndo->ndo_sa_default;
- RC5_32_set_key(&schedule, strlen(secret), secret,
- RC5_16_ROUNDS);
-
- p = ivoff + ivlen;
- RC5_32_cbc_encrypt(p, p, (long)(ep - p), &schedule, ivoff,
- RC5_DECRYPT);
- advance = ivoff - (u_char *)esp + ivlen;
- break;
- }
-#else
+ /* if not found fail */
+ if (sa == NULL)
goto fail;
-#endif /*HAVE_LIBCRYPTO*/
-
- case CAST128:
-#if defined(HAVE_LIBCRYPTO) && defined(HAVE_CAST_H) && !defined(HAVE_BUGGY_CAST128)
- {
- CAST_KEY schedule;
- CAST_set_key(&schedule, strlen(secret), secret);
-
- p = ivoff + ivlen;
- CAST_cbc_encrypt(p, p, (long)(ep - p), &schedule, ivoff,
- CAST_DECRYPT);
- advance = ivoff - (u_char *)esp + ivlen;
- break;
- }
-#else
- goto fail;
-#endif /*HAVE_LIBCRYPTO*/
-
- case DES3CBC:
-#if defined(HAVE_LIBCRYPTO)
- {
- des_key_schedule s1, s2, s3;
-
- des_check_key = 1;
- des_set_odd_parity((void *)secret);
- des_set_odd_parity((void *)(secret + 8));
- des_set_odd_parity((void *)(secret + 16));
- if(des_set_key((void *)secret, s1) != 0) {
- printf("failed to schedule key 1\n");
- }
- if(des_set_key((void *)(secret + 8), s2)!=0) {
- printf("failed to schedule key 2\n");
- }
- if(des_set_key((void *)(secret + 16), s3)!=0) {
- printf("failed to schedule key 3\n");
- }
-
- p = ivoff + ivlen;
- des_ede3_cbc_encrypt((void *)p, (void *)p,
- (long)(ep - p),
- s1, s2, s3,
- (void *)ivoff, DES_DECRYPT);
- advance = ivoff - (u_char *)esp + ivlen;
- break;
- }
-#else
+ /* if we can't get nexthdr, we do not need to decrypt it */
+ if (ep - bp2 < len)
goto fail;
-#endif /*HAVE_LIBCRYPTO*/
-
- case NONE:
- default:
- advance = sizeof(struct esp) + espsecret_xform->replaysize;
- break;
+ if (ep - bp2 > len) {
+ /* FCS included at end of frame (NetBSD 1.6 or later) */
+ ep = bp2 + len;
}
- ep = ep - espsecret_xform->authlen;
+ /* pointer to the IV, if there is one */
+ ivoff = (const u_char *)(esp + 1) + 0;
+ /* length of the IV, if there is one; 0, if there isn't */
+ ivlen = sa->ivlen;
+ secret = sa->secret;
+ ep = ep - sa->authlen;
+
+ if (sa->evp) {
+ ctx = EVP_CIPHER_CTX_new();
+ if (ctx != NULL) {
+ if (set_cipher_parameters(ctx, sa->evp, secret, NULL, 0) < 0)
+ (*ndo->ndo_warning)(ndo, "espkey init failed");
+
+ p = ivoff;
+ set_cipher_parameters(ctx, NULL, NULL, p, 0);
+ len = ep - (p + ivlen);
+
+ /*
+ * Allocate buffers for the encrypted and decrypted
+ * data. Both buffers' sizes must be a multiple of
+ * the cipher block size, and the output buffer must
+ * be separate from the input buffer.
+ */
+ block_size = (unsigned int)EVP_CIPHER_CTX_block_size(ctx);
+ buffer_size = len + (block_size - len % block_size);
+
+ /*
+ * Attempt to allocate the input buffer.
+ */
+ input_buffer = (u_char *)malloc(buffer_size);
+ if (input_buffer == NULL) {
+ EVP_CIPHER_CTX_free(ctx);
+ (*ndo->ndo_error)(ndo, "can't allocate memory for encrypted data buffer");
+ }
+ /*
+ * Copy the input data to the encrypted data buffer,
+ * and pad it with zeroes.
+ */
+ memcpy(input_buffer, p + ivlen, len);
+ memset(input_buffer + len, 0, buffer_size - len);
+
+ /*
+ * Attempt to allocate the output buffer.
+ */
+ output_buffer = (u_char *)malloc(buffer_size);
+ if (output_buffer == NULL) {
+ free(input_buffer);
+ EVP_CIPHER_CTX_free(ctx);
+ (*ndo->ndo_error)(ndo, "can't allocate memory for decryption buffer");
+ }
+
+ EVP_Cipher(ctx, output_buffer, input_buffer, len);
+ free(input_buffer);
+ EVP_CIPHER_CTX_free(ctx);
+ /*
+ * XXX - of course this is wrong, because buf is a
+ * const buffer, but changing this would require a
+ * more complicated fix.
+ */
+ memcpy(p + ivlen, output_buffer, len);
+ free(output_buffer);
+ advance = ivoff - (const u_char *)esp + ivlen;
+ } else
+ advance = sizeof(struct newesp);
+ } else
+ advance = sizeof(struct newesp);
+
/* sanity check for pad length */
if (ep - bp < *(ep - 2))
goto fail;
if (nhdr)
*nhdr = *(ep - 1);
- printf(": ");
+ ND_PRINT((ndo, ": "));
return advance;
+#endif
fail:
- if (nhdr)
- *nhdr = -1;
- return 65536;
+ return -1;
}
+#ifdef HAVE_LIBCRYPTO
+USES_APPLE_RST
+#endif
+
+/*
+ * Local Variables:
+ * c-style: whitesmith
+ * c-basic-offset: 8
+ * End:
+ */
projects / tcpdump / blobdiff