* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
+/* \summary: IPSEC Encapsulating Security Payload (ESP) printer */
+
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
-#include <tcpdump-stdinc.h>
+#include <netdissect-stdinc.h>
#include <string.h>
#include <stdlib.h>
#endif
#endif
-#include "ip.h"
-#ifdef INET6
-#include "ip6.h"
-#endif
-
#include "netdissect.h"
+#include "strtoaddr.h"
#include "extract.h"
#include "ascii_strcasecmp.h"
+#include "ip.h"
+#include "ip6.h"
+
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* All rights reserved.
#ifdef HAVE_LIBCRYPTO
union inaddr_u {
struct in_addr in4;
-#ifdef INET6
struct in6_addr in6;
-#endif
};
struct sa_list {
struct sa_list *next;
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
+
+#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!
*/
{
struct sa_list *sa;
const u_char *iv;
- int len;
- EVP_CIPHER_CTX ctx;
+ 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;
if(end <= buf) return 0;
- memset(&ctx, 0, sizeof(ctx));
- if (EVP_CipherInit(&ctx, sa->evp, sa->secret, NULL, 0) < 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");
- EVP_CipherInit(&ctx, NULL, NULL, iv, 0);
- EVP_Cipher(&ctx, buf, buf, len);
- EVP_CIPHER_CTX_cleanup(&ctx);
+ 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;
return 1;
-
}
USES_APPLE_RST
return (hex - 'a' + 10);
else {
(*ndo->ndo_error)(ndo, "invalid hex digit %c in espsecret\n", hex);
- return 0;
}
}
USES_APPLE_RST
/*
- * for the moment, ignore the auth algorith, just hard code the authenticator
+ * for the moment, ignore the auth algorithm, just hard code the authenticator
* length. Need to research how openssl looks up HMAC stuff.
*/
static int
secretfile = fopen(filename, FOPEN_READ_TXT);
if (secretfile == NULL) {
- perror(filename);
- exit(3);
+ (*ndo->ndo_error)(ndo, "print_esp: can't open %s: %s\n",
+ filename, strerror(errno));
}
while (fgets(fileline, sizeof(fileline)-1, secretfile) != NULL) {
uint32_t spino;
spistr = strsep(&spikey, "@");
+ if (spistr == NULL) {
+ (*ndo->ndo_warning)(ndo, "print_esp: failed to find the @ token");
+ return;
+ }
spino = strtoul(spistr, &foo, 0);
if (spistr == foo || !spikey) {
sa1.spi = spino;
-#ifdef INET6
- if (inet_pton(AF_INET6, spikey, &sa1.daddr.in6) == 1) {
+ if (strtoaddr6(spikey, &sa1.daddr.in6) == 1) {
sa1.daddr_version = 6;
- } else
-#endif
- if (inet_pton(AF_INET, spikey, &sa1.daddr.in4) == 1) {
- sa1.daddr_version = 4;
- } else {
- (*ndo->ndo_warning)(ndo, "print_esp: can not decode IP# %s\n", spikey);
- return;
- }
+ } 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) {
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
#ifdef HAVE_LIBCRYPTO
const struct ip *ip;
struct sa_list *sa = NULL;
-#ifdef INET6
const struct ip6_hdr *ip6 = NULL;
-#endif
int advance;
int len;
u_char *secret;
int ivlen = 0;
const u_char *ivoff;
const u_char *p;
- EVP_CIPHER_CTX ctx;
+ EVP_CIPHER_CTX *ctx;
+ unsigned int block_size, buffer_size;
+ u_char *input_buffer, *output_buffer;
#endif
esp = (const struct newesp *)bp;
ip = (const struct ip *)bp2;
switch (IP_V(ip)) {
-#ifdef INET6
case 6:
ip6 = (const struct ip6_hdr *)bp2;
/* we do not attempt to decrypt jumbograms */
}
}
break;
-#endif /*INET6*/
case 4:
/* nexthdr & padding are in the last fragment */
if (EXTRACT_16BITS(&ip->ip_off) & IP_MF)
ep = bp2 + len;
}
+ /* 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) {
- memset(&ctx, 0, sizeof(ctx));
- if (EVP_CipherInit(&ctx, sa->evp, secret, NULL, 0) < 0)
- (*ndo->ndo_warning)(ndo, "espkey init failed");
-
- p = ivoff;
- EVP_CipherInit(&ctx, NULL, NULL, p, 0);
- EVP_Cipher(&ctx, p + ivlen, p + ivlen, ep - (p + ivlen));
- EVP_CIPHER_CTX_cleanup(&ctx);
- advance = ivoff - (const u_char *)esp + ivlen;
+ 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);
projects / tcpdump / blobdiff