]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-esp.c
Handle very large -f files by rejecting them.
[tcpdump] / print-esp.c
index 636ff8eda2fa23a0e62138c2eb49e2cefb86b9a1..6fabff1e8d18aab6559020aeec5493dde8373d69 100644 (file)
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  */
 
-#ifndef lint
-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-esp.c,v 1.29 2002-09-05 00:00:12 guy Exp $ (LBL)";
-#endif
+/* \summary: IPSEC Encapsulating Security Payload (ESP) printer */
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include <string.h>
-
-#include <tcpdump-stdinc.h>
+#include <netdissect-stdinc.h>
 
+#include <string.h>
 #include <stdlib.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
+
+/*
+ * 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;
 
-static struct esp_algorithm *espsecret_xform=NULL;  /* cache of decoded alg. */
-static char                 *espsecret_key=NULL;
+       /*
+        * 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;
 
-enum cipher { NONE,
-             DESCBC,
-             BLOWFISH,
-             RC5,
-             CAST128,
-             DES3CBC};
+       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);
 
+       /*
+        * 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);
 
+       ndo->ndo_packetp = buf;
+       ndo->ndo_snapend = end;
 
-struct esp_algorithm {
-       const char   *name;
-       enum  cipher algo;
-       int          ivlen;
-       int          authlen;
-       int          replaysize;
-};
+       return 1;
+}
+USES_APPLE_RST
 
-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},
-       {NULL,                    NONE,    0,  0, 0}
-};
+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");
+
+       *nsa = *sa;
+
+       if (sa_def)
+               ndo->ndo_sa_default = nsa;
 
-static int hexdigit(char hex)
+       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;
+}
 
-static void esp_print_decodesecret(void)
+/*
+ * 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! */
+
+               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;
-       struct esp_algorithm *null_xf =
-               &esp_xforms[sizeof(esp_xforms)/sizeof(esp_xforms[0]) - 1];
-
-       if(espsecret == NULL) {
-               /* set to NULL transform */
-               espsecret_xform = null_xf;
-               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 NULL transform */
-               espsecret_xform = null_xf;
+       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);
-               /* set to NULL transform */
-               espsecret_xform = null_xf;
+
+       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;
+               }
+
+               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;
                }
-       } else {
-               espsecret_key = colon;
        }
+
+       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 newesp *esp;
        register const u_char *ep;
-       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 newesp *)bp;
+       esp = (const struct newesp *)bp;
+
+#ifdef HAVE_LIBCRYPTO
        secret = NULL;
+       advance = 0;
+#endif
 
 #if 0
        /* keep secret out of a register */
@@ -209,224 +700,155 @@ esp_print(register const u_char *bp, register const u_char *bp2,
 #endif
 
        /* 'ep' points to the end of available data. */
-       ep = snapend;
+       ep = ndo->ndo_snapend;
 
-       if ((u_char *)(esp + 1) >= ep) {
-               fputs("[|ESP]", stdout);
+       if ((const u_char *)(esp + 1) >= ep) {
+               ND_PRINT((ndo, "[|ESP]"));
                goto fail;
        }
-       printf("ESP(spi=0x%08x", (u_int32_t)ntohl(esp->esp_spi));
-       printf(",seq=0x%x", (u_int32_t)ntohl(esp->esp_seq));
-       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->name == NULL) {
+
+       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];
-#if OPENSSL_VERSION_NUMBER >= 0x00907000L
-               DES_key_schedule schedule;
-#else
-               des_key_schedule schedule;
-#endif
-
-               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;
-               }
-               p = ivoff + ivlen;
+       /* if we didn't find the specific one, then look for
+        * an unspecified one.
+        */
+       if (sa == NULL)
+               sa = ndo->ndo_sa_default;
 
-#if OPENSSL_VERSION_NUMBER >= 0x00907000L
-               DES_set_key_unchecked((DES_cblock *)secret, schedule);
-
-               DES_cbc_encrypt((const unsigned char *)p, p,
-                       (long)(ep - p), schedule, (DES_cblock *)iv,
-                       DES_DECRYPT);
-#else
-               des_check_key = 0;
-               des_set_key((void *)secret, schedule);
-
-               des_cbc_encrypt((void *)p, (void *)p,
-                       (long)(ep - p), schedule, (void *)iv,
-                       DES_DECRYPT);
-#endif
-               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;
-
-               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)
-           {
-#if OPENSSL_VERSION_NUMBER >= 0x00907000L
-               DES_key_schedule s1, s2, s3;
-
-               DES_set_odd_parity((DES_cblock *)secret);
-               DES_set_odd_parity((DES_cblock *)(secret + 8));
-               DES_set_odd_parity((DES_cblock *)(secret + 16));
-               if(DES_set_key_checked((DES_cblock *)secret, s1) != 0) {
-                 printf("failed to schedule key 1\n");
-               }
-               if(DES_set_key_checked((DES_cblock *)(secret + 8), s2)!=0) {
-                 printf("failed to schedule key 2\n");
-               }
-               if(DES_set_key_checked((DES_cblock *)(secret + 16), s3)!=0) {
-                 printf("failed to schedule key 3\n");
-               }
-
-               p = ivoff + ivlen;
-               DES_ede3_cbc_encrypt((const unsigned char *)p, p,
-                                    (long)(ep - p),
-                                    &s1, &s2, &s3,
-                                    (DES_cblock *)ivoff, DES_DECRYPT);
-#else
-               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);
-#endif
-               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 newesp) + 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;
@@ -437,11 +859,20 @@ esp_print(register const u_char *bp, register const u_char *bp2,
        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:
+ */