*/
#ifndef lint
-static char rcsid[] =
- "@(#) Header: print-ah.c,v 1.37 94/06/10 17:01:42 mccanne Exp (LBL)";
+static const char rcsid[] _U_ =
+ "@(#) $Header: /tcpdump/master/tcpdump/print-esp.c,v 1.51 2004-04-10 08:41:22 guy Exp $ (LBL)";
#endif
-#include <sys/param.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/socket.h>
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <string.h>
-#include <netinet/in.h>
-#include <netinet/in_systm.h>
-#include <netinet/ip.h>
-#include <netinet/ip_var.h>
-#include <netinet/udp.h>
-#include <netinet/udp_var.h>
+#include <tcpdump-stdinc.h>
-#undef NOERROR /* Solaris sucks */
-#include <arpa/nameser.h>
-#include <arpa/tftp.h>
+#include <stdlib.h>
-#ifdef SOLARIS
-#include <tiuser.h>
+#ifdef HAVE_LIBCRYPTO
+#ifdef HAVE_OPENSSL_EVP_H
+#include <openssl/evp.h>
+#endif
#endif
-#include <rpc/rpc.h>
-#include <errno.h>
#include <stdio.h>
-#include "interface.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
+
+#include "netdissect.h"
#include "addrtoname.h"
+#include "extract.h"
-extern int packettype;
+#ifndef HAVE_SOCKADDR_STORAGE
+#ifdef INET6
+struct sockaddr_storage {
+ union {
+ struct sockaddr_in sin;
+ struct sockaddr_in6 sin6;
+ } un;
+};
+#else
+#define sockaddr_storage sockaddr
+#endif
+#endif /* HAVE_SOCKADDR_STORAGE */
+#ifdef HAVE_LIBCRYPTO
+struct sa_list {
+ struct sa_list *next;
+ struct sockaddr_storage daddr;
+ u_int32_t spi;
+ const EVP_CIPHER *evp;
+ int ivlen;
+ int authlen;
+ char secret[256]; /* is that big enough for all secrets? */
+ int secretlen;
+};
-void
-esp_print(register const u_char *bp, int length, register const u_char *bp2)
+static void esp_print_addsa(netdissect_options *ndo,
+ struct sa_list *sa, int sa_def)
{
- register const struct ip *ip;
- register const u_char *cp, *nh;
- u_short ahlen, authlen;
- u_long spi, seqno;
+ /* 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;
+
+ nsa->next = ndo->ndo_sa_list_head;
+ ndo->ndo_sa_list_head = nsa;
+}
+
+
+static int hexdigit(netdissect_options *ndo, char hex)
+{
+ if (hex >= '0' && hex <= '9')
+ return (hex - '0');
+ else if (hex >= 'A' && hex <= 'F')
+ return (hex - 'A' + 10);
+ else if (hex >= 'a' && hex <= 'f')
+ return (hex - 'a' + 10);
+ else {
+ (*ndo->ndo_error)(ndo, "invalid hex digit %c in espsecret\n", hex);
+ return 0;
+ }
+}
+
+static int hex2byte(netdissect_options *ndo, char *hexstring)
+{
+ int byte;
+
+ byte = (hexdigit(ndo, hexstring[0]) << 4) + hexdigit(ndo, hexstring[1]);
+ return byte;
+}
+
+/*
+ * decode the form: SPINUM@IP <tab> ALGONAME:0xsecret
+ *
+ * special form: file /name
+ * causes us to go read from this file instead.
+ *
+ */
+static void esp_print_decode_onesecret(netdissect_options *ndo, char *line)
+{
+ 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;
+ /* memset(&sa1.daddr, 0, sizeof(sa1.daddr)); */
+ /* sa1.spi = 0; */
+ sa_def = 1;
+ } else
+ decode = line;
+
+ if (spikey && strcasecmp(spikey, "file") == 0) {
+ /* open file and read it */
+ FILE *secretfile;
+ char fileline[1024];
+ char *nl;
+
+ secretfile = fopen(line, FOPEN_READ_TXT);
+ if (secretfile == NULL) {
+ perror(line);
+ exit(3);
+ }
+
+ while (fgets(fileline, sizeof(fileline)-1, secretfile) != NULL) {
+ /* 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);
+ }
+ fclose(secretfile);
+
+ return;
+ }
+
+ if (spikey) {
+ char *spistr, *foo;
+ u_int32_t spino;
+ struct sockaddr_in *sin;
+#ifdef INET6
+ struct sockaddr_in6 *sin6;
+#endif
+
+ spistr = strsep(&spikey, "@");
+
+ 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;
+
+ 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;
+ } else {
+ (*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;
+ size_t i;
+ const EVP_CIPHER *evp;
+ int authlen = 0;
+
+ /* skip any blank spaces */
+ while (isspace((unsigned char)*decode))
+ decode++;
+
+ colon = strchr(decode, ':');
+ if (colon == NULL) {
+ (*ndo->ndo_warning)(ndo, "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) {
+ (*ndo->ndo_warning)(ndo, "failed to find cipher algo %s\n", decode);
+ sa1.evp = NULL;
+ sa1.authlen = 0;
+ sa1.ivlen = 0;
+ return;
+ }
- ip = (struct ip *)bp2;
+ sa1.evp = evp;
+ sa1.authlen = authlen;
+ sa1.ivlen = EVP_CIPHER_iv_length(evp);
- (void)printf("ESP %s > %s\n\t\t",
- ipaddr_string(&ip->ip_src),
- ipaddr_string(&ip->ip_dst));
+ colon++;
+ if (colon[0] == '0' && colon[1] == 'x') {
+ /* decode some hex! */
+ colon += 2;
+ len = strlen(colon) / 2;
- if (length < 8) {
- (void)printf(" [|esp] truncated-esp %d", length);
- return;
- }
+ if (len > 256) {
+ (*ndo->ndo_warning)(ndo, "secret is too big: %d\n", len);
+ return;
+ }
- spi = ntohl(*((u_long *)(bp)));
- seqno = ntohl(*((u_long *)(bp+4)));
+ i = 0;
+ while (colon[0] != '\0' && colon[1]!='\0') {
+ espsecret_key[i] = hex2byte(ndo, colon);
+ colon += 2;
+ i++;
+ }
- nh = bp+ahlen;
+ memcpy(sa1.secret, espsecret_key, i);
+ sa1.secretlen = i;
+ } else {
+ i = strlen(colon);
- (void)printf("spi:%08x seqno:%d ciphertext: ", spi, seqno);
- (void)default_print_unaligned(bp+8, length-8);
+ 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);
+ }
+ }
+ }
- /* XXX it would be nice to decrypt! */
+ esp_print_addsa(ndo, &sa1, sa_def);
}
+
+static void esp_print_decodesecret(netdissect_options *ndo)
+{
+ char *line;
+ char *p;
+
+ p = ndo->ndo_espsecret;
+
+ while (ndo->ndo_espsecret && ndo->ndo_espsecret[0] != '\0') {
+ /* pick out the first line or first thing until a comma */
+ if ((line = strsep(&ndo->ndo_espsecret, "\n,")) == NULL) {
+ line = ndo->ndo_espsecret;
+ ndo->ndo_espsecret = NULL;
+ }
+
+ esp_print_decode_onesecret(ndo, line);
+ }
+}
+
+static void esp_init(netdissect_options *ndo _U_)
+{
+
+ OpenSSL_add_all_algorithms();
+ EVP_add_cipher_alias(SN_des_ede3_cbc, "3des");
+}
+#endif
+
+int
+esp_print(netdissect_options *ndo,
+ const u_char *bp, 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;
+#ifdef HAVE_LIBCRYPTO
+ struct ip *ip;
+ struct sa_list *sa = NULL;
+ int espsecret_keylen;
+#ifdef INET6
+ struct ip6_hdr *ip6 = NULL;
+#endif
+ int advance;
+ int len;
+ char *secret;
+ int ivlen = 0;
+ u_char *ivoff;
+ u_char *p;
+ EVP_CIPHER_CTX ctx;
+ int blocksz;
+ static int initialized = 0;
+#endif
+
+ esp = (struct newesp *)bp;
+
+#ifdef HAVE_LIBCRYPTO
+ secret = NULL;
+ advance = 0;
+
+ if (!initialized) {
+ esp_init(ndo);
+ initialized = 1;
+ }
+#endif
+
+#if 0
+ /* keep secret out of a register */
+ p = (u_char *)&secret;
+#endif
+
+ /* 'ep' points to the end of available data. */
+ ep = ndo->ndo_snapend;
+
+ if ((u_char *)(esp + 1) >= ep) {
+ fputs("[|ESP]", stdout);
+ goto fail;
+ }
+ (*ndo->ndo_printf)(ndo, "ESP(spi=0x%08x", EXTRACT_32BITS(&esp->esp_spi));
+ (*ndo->ndo_printf)(ndo, ",seq=0x%x)", EXTRACT_32BITS(&esp->esp_seq));
+
+#ifndef HAVE_LIBCRYPTO
+ goto fail;
+#else
+ /* initiailize SAs */
+ if (ndo->ndo_sa_list_head == NULL) {
+ if (!ndo->ndo_espsecret)
+ goto fail;
+
+ esp_print_decodesecret(ndo);
+ }
+
+ if (ndo->ndo_sa_list_head == NULL)
+ goto fail;
+
+ ip = (struct ip *)bp2;
+ switch (IP_V(ip)) {
+#ifdef INET6
+ case 6:
+ ip6 = (struct ip6_hdr *)bp2;
+ /* we do not attempt to decrypt jumbograms */
+ 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) + 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) {
+ 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,
+ 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)
+ goto fail;
+ 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) {
+ 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) {
+ break;
+ }
+ }
+ break;
+ default:
+ goto fail;
+ }
+
+ /* if we didn't find the specific one, then look for
+ * an unspecified one.
+ */
+ if (sa == NULL)
+ sa = ndo->ndo_sa_default;
+
+ /* if not found fail */
+ if (sa == NULL)
+ goto fail;
+
+ /* if we can't get nexthdr, we do not need to decrypt it */
+ if (ep - bp2 < len)
+ goto fail;
+ if (ep - bp2 > len) {
+ /* FCS included at end of frame (NetBSD 1.6 or later) */
+ ep = bp2 + len;
+ }
+
+ ivoff = (u_char *)(esp + 1) + 0;
+ 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)
+ (*ndo->ndo_warning)(ndo, "espkey init failed");
+
+ blocksz = EVP_CIPHER_CTX_block_size(&ctx);
+
+ 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;
+ } else
+ advance = sizeof(struct newesp);
+
+ /* sanity check for pad length */
+ if (ep - bp < *(ep - 2))
+ goto fail;
+
+ if (padlen)
+ *padlen = *(ep - 2) + 2;
+
+ if (nhdr)
+ *nhdr = *(ep - 1);
+
+ (ndo->ndo_printf)(ndo, ": ");
+ return advance;
+#endif
+
+fail:
+ return -1;
+}
+
+/*
+ * Local Variables:
+ * c-style: whitesmith
+ * c-basic-offset: 8
+ * End:
+ */
projects / tcpdump / blobdiff