X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/0d821a59a77eab728e4d0d2e16e14b67a1c3ecd0..refs/heads/tcpdump-4.9:/print-esp.c diff --git a/print-esp.c b/print-esp.c index 16006781..6fabff1e 100644 --- a/print-esp.c +++ b/print-esp.c @@ -21,71 +21,264 @@ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. */ -#ifndef lint -static const char rcsid[] = - "@(#) $Header: /tcpdump/master/tcpdump/print-esp.c,v 1.41 2003-07-17 13:31:02 itojun Exp $ (LBL)"; -#endif +/* \summary: IPSEC Encapsulating Security Payload (ESP) printer */ #ifdef HAVE_CONFIG_H #include "config.h" #endif -#include - -#include +#include +#include #include +/* 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 #ifdef HAVE_OPENSSL_EVP_H #include +#else +#undef HAVE_LIBCRYPTO #endif #endif -#include +#include "netdissect.h" +#include "strtoaddr.h" +#include "extract.h" + +#include "ascii_strcasecmp.h" #include "ip.h" -#include "esp.h" -#ifdef INET6 #include "ip6.h" -#endif -#if defined(__MINGW32__) || defined(__WATCOMC__) -extern char *strsep(char **stringp, const char *delim); /* Missing/strsep.c */ -#endif +/* + * 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. + */ -#include "interface.h" -#include "addrtoname.h" -#include "extract.h" +/* + * RFC1827/2406 Encapsulated Security Payload. + */ -#ifndef HAVE_SOCKADDR_STORAGE -#ifdef INET6 -struct sockaddr_storage { - union { - struct sockaddr_in sin; - struct sockaddr_in6 sin6; - } un; +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 */ }; -#else -#define sockaddr_storage sockaddr -#endif -#endif /* HAVE_SOCKADDR_STORAGE */ +#ifdef HAVE_LIBCRYPTO +union inaddr_u { + struct in_addr in4; + struct in6_addr in6; +}; struct sa_list { struct sa_list *next; - struct sockaddr_storage daddr; - u_int32_t spi; + 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; - char secret[256]; /* is that big enough for all secrets? */ + u_char authsecret[256]; + int authsecret_len; + u_char secret[256]; /* is that big enough for all secrets? */ int secretlen; }; -static struct sa_list *sa_list_head = NULL; -static struct sa_list *sa_default = NULL; +#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! + */ +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; + + /* + * 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); + + /* + * 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; -static void esp_print_addsa(struct sa_list *sa, int sa_def) + return 1; +} +USES_APPLE_RST + +static void esp_print_addsa(netdissect_options *ndo, + struct sa_list *sa, int sa_def) { /* copy the "sa" */ @@ -93,19 +286,19 @@ static void esp_print_addsa(struct sa_list *sa, int sa_def) nsa = (struct sa_list *)malloc(sizeof(struct sa_list)); if (nsa == NULL) - error("ran out of memory to allocate sa structure"); + (*ndo->ndo_error)(ndo, "ran out of memory to allocate sa structure"); *nsa = *sa; if (sa_def) - sa_default = nsa; + ndo->ndo_sa_default = nsa; - nsa->next = sa_list_head; - sa_list_head = nsa; + nsa->next = ndo->ndo_sa_list_head; + ndo->ndo_sa_list_head = nsa; } -static int hexdigit(char hex) +static u_int hexdigit(netdissect_options *ndo, char hex) { if (hex >= '0' && hex <= '9') return (hex - '0'); @@ -114,27 +307,206 @@ static int hexdigit(char hex) else if (hex >= 'a' && hex <= 'f') return (hex - 'a' + 10); else { - printf("invalid hex digit %c in espsecret\n", hex); - return 0; + (*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 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; + + 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); + + return; + } + + 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; + } + + 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(char *line) +static void esp_print_decode_onesecret(netdissect_options *ndo, char *line, + const char *file, int lineno) { struct sa_list sa1; int sa_def; @@ -150,25 +522,29 @@ static void esp_print_decode_onesecret(char *line) 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 && strcasecmp(spikey, "file") == 0) { + 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(line, FOPEN_READ_TXT); + secretfile = fopen(filename, FOPEN_READ_TXT); if (secretfile == NULL) { - perror(line); - 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) { + subfile_lineno++; /* remove newline from the line */ nl = strchr(fileline, '\n'); if (nl) @@ -176,190 +552,146 @@ static void esp_print_decode_onesecret(char *line) if (fileline[0] == '#') continue; if (fileline[0] == '\0') continue; - esp_print_decode_onesecret(fileline); + esp_print_decode_onesecret(ndo, fileline, filename, subfile_lineno); } fclose(secretfile); return; } + if (spikey && ascii_strcasecmp(spikey, "ikev2") == 0) { + esp_print_decode_ikeline(ndo, line, file, lineno); + return; + } + if (spikey) { + char *spistr, *foo; - u_int32_t spino; - struct sockaddr_in *sin; -#ifdef INET6 - struct sockaddr_in6 *sin6; -#endif + 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) { - printf("print_esp: failed to decode spi# %s\n", foo); + (*ndo->ndo_warning)(ndo, "print_esp: failed to decode spi# %s\n", foo); return; } sa1.spi = spino; - sin = (struct sockaddr_in *)&sa1.daddr; -#ifdef INET6 - sin6 = (struct sockaddr_in6 *)&sa1.daddr; - if (inet_pton(AF_INET6, spikey, &sin6->sin6_addr) == 1) { -#ifdef HAVE_SOCKADDR_SA_LEN - sin6->sin6_len = sizeof(struct sockaddr_in6); -#endif - sin6->sin6_family = AF_INET6; - } else -#endif - if (inet_pton(AF_INET, spikey, &sin->sin_addr) == 1) { -#ifdef HAVE_SOCKADDR_SA_LEN - sin->sin_len = sizeof(struct sockaddr_in); -#endif - sin->sin_family = AF_INET; + if (strtoaddr6(spikey, &sa1.daddr.in6) == 1) { + sa1.daddr_version = 6; + } else if (strtoaddr(spikey, &sa1.daddr.in4) == 1) { + sa1.daddr_version = 4; } else { - printf("print_esp: can not decode IP# %s\n", spikey); + (*ndo->ndo_warning)(ndo, "print_esp: can not decode IP# %s\n", spikey); return; } } if (decode) { - char *colon, *p; - char espsecret_key[256]; - int len, i; - const EVP_CIPHER *evp; - int ivlen = 8; - int authlen = 0; - /* skip any blank spaces */ while (isspace((unsigned char)*decode)) decode++; - colon = strchr(decode, ':'); - if (colon == NULL) { - printf("failed to decode espsecret: %s\n", decode); - return; - } - *colon = '\0'; - - len = colon - decode; - 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) { - printf("failed to find cipher algo %s\n", decode); - sa1.evp = NULL; - sa1.authlen = 0; - sa1.ivlen = 0; + if(!espprint_decode_encalgo(ndo, decode, &sa1)) { return; } - - sa1.evp = evp; - sa1.authlen = authlen; - sa1.ivlen = ivlen; - - colon++; - if (colon[0] == '0' && colon[1] == 'x') { - /* decode some hex! */ - colon += 2; - len = strlen(colon) / 2; - - if (len > 256) { - printf("secret is too big: %d\n", len); - return; - } - - i = 0; - while (colon[0] != '\0' && colon[1]!='\0') { - espsecret_key[i] = hex2byte(colon); - colon += 2; - i++; - } - - memcpy(sa1.secret, espsecret_key, i); - sa1.secretlen = i; - } else { - i = strlen(colon); - - if (i < sizeof(sa1.secret)) { - memcpy(sa1.secret, colon, i); - sa1.secretlen = i; - } else { - memcpy(sa1.secret, colon, sizeof(sa1.secret)); - sa1.secretlen = sizeof(sa1.secret); - } - } } - esp_print_addsa(&sa1, sa_def); + 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 -static void esp_print_decodesecret(void) +void esp_print_decodesecret(netdissect_options *ndo) { char *line; char *p; + static int initialized = 0; - p = espsecret; + if (!initialized) { + esp_init(ndo); + initialized = 1; + } + + p = ndo->ndo_espsecret; - while (espsecret && espsecret[0] != '\0') { + while (p && p[0] != '\0') { /* pick out the first line or first thing until a comma */ - if ((line = strsep(&espsecret, "\n,")) == NULL) { - line = espsecret; - espsecret = NULL; + if ((line = strsep(&p, "\n,")) == NULL) { + line = p; + p = NULL; } - esp_print_decode_onesecret(line); + esp_print_decode_onesecret(ndo, line, "cmdline", 0); } -} -static void esp_init(void) -{ - - OpenSSL_add_all_algorithms(); - EVP_add_cipher_alias(SN_des_ede3_cbc, "3des"); + ndo->ndo_espsecret = NULL; } +#endif + +#ifdef HAVE_LIBCRYPTO +USES_APPLE_DEPRECATED_API +#endif int -esp_print(const u_char *bp, 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; +#ifdef HAVE_LIBCRYPTO + const struct ip *ip; struct sa_list *sa = NULL; - int espsecret_keylen; -#ifdef INET6 - struct ip6_hdr *ip6 = NULL; -#endif + const struct ip6_hdr *ip6 = NULL; int advance; int len; - char *secret; + u_char *secret; int ivlen = 0; - u_char *ivoff; -#ifdef HAVE_LIBCRYPTO + const u_char *ivoff; const u_char *p; - EVP_CIPHER_CTX ctx; - int blocksz; - static int initialized = 0; + EVP_CIPHER_CTX *ctx; + unsigned int block_size, buffer_size; + u_char *input_buffer, *output_buffer; #endif - esp = (struct newesp *)bp; - secret = NULL; - advance = 0; + esp = (const struct newesp *)bp; #ifdef HAVE_LIBCRYPTO - if (!initialized) { - esp_init(); - initialized = 1; - } + secret = NULL; + advance = 0; #endif #if 0 @@ -368,32 +700,34 @@ esp_print(const u_char *bp, const u_char *bp2, int *nhdr, int *padlen) #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", EXTRACT_32BITS(&esp->esp_spi)); - printf(",seq=0x%x", EXTRACT_32BITS(&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)); +#ifndef HAVE_LIBCRYPTO + goto fail; +#else /* initiailize SAs */ - if (sa_list_head == NULL) { - if (!espsecret) + if (ndo->ndo_sa_list_head == NULL) { + if (!ndo->ndo_espsecret) goto fail; - esp_print_decodesecret(); + esp_print_decodesecret(ndo); } - if (sa_list_head == 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; + ip6 = (const struct ip6_hdr *)bp2; /* we do not attempt to decrypt jumbograms */ if (!EXTRACT_16BITS(&ip6->ip6_plen)) goto fail; @@ -401,17 +735,15 @@ esp_print(const u_char *bp, const u_char *bp2, int *nhdr, int *padlen) len = sizeof(struct ip6_hdr) + EXTRACT_16BITS(&ip6->ip6_plen); /* see if we can find the SA, and if so, decode it */ - for (sa = sa_list_head; sa != NULL; sa = sa->next) { - struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&sa->daddr; - if (sa->spi == ntohl(esp->esp_spi) && - sin6->sin6_family == AF_INET6 && - memcmp(&sin6->sin6_addr, &ip6->ip6_dst, + 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 (EXTRACT_16BITS(&ip->ip_off) & IP_MF) @@ -419,11 +751,11 @@ esp_print(const u_char *bp, const u_char *bp2, int *nhdr, int *padlen) len = EXTRACT_16BITS(&ip->ip_len); /* see if we can find the SA, and if so, decode it */ - for (sa = sa_list_head; sa != NULL; sa = sa->next) { - struct sockaddr_in *sin = (struct sockaddr_in *)&sa->daddr; - if (sa->spi == ntohl(esp->esp_spi) && - sin->sin_family == AF_INET && - sin->sin_addr.s_addr == ip->ip_dst.s_addr) { + 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; } } @@ -436,8 +768,8 @@ esp_print(const u_char *bp, const u_char *bp2, int *nhdr, int *padlen) * an unspecified one. */ if (sa == NULL) - sa = sa_default; - + sa = ndo->ndo_sa_default; + /* if not found fail */ if (sa == NULL) goto fail; @@ -450,26 +782,73 @@ esp_print(const u_char *bp, const u_char *bp2, int *nhdr, int *padlen) ep = bp2 + len; } - ivoff = (u_char *)(esp + 1) + 0; + /* 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; - espsecret_keylen = sa->secretlen; + ep = ep - sa->authlen; if (sa->evp) { - memset(&ctx, 0, sizeof(ctx)); - if (EVP_CipherInit(&ctx, sa->evp, secret, NULL, 0) < 0) - printf("espkey init failed"); - - blocksz = EVP_CIPHER_CTX_block_size(&ctx); + 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"); + } - p = ivoff; - EVP_CipherInit(&ctx, NULL, NULL, p, 0); - EVP_Cipher(&ctx, p + ivlen, p + ivlen, ep - (p + ivlen)); - advance = ivoff - (u_char *)esp + ivlen; + 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); - ep = ep - sa->authlen; /* sanity check for pad length */ if (ep - bp < *(ep - 2)) goto fail; @@ -480,11 +859,20 @@ esp_print(const u_char *bp, const u_char *bp2, int *nhdr, int *padlen) 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: + */