*/
#include "includes.h"
-RCSID("$OpenBSD: kex.c,v 1.12 2000/10/11 20:27:23 markus Exp $");
-
-#include "ssh.h"
-#include "ssh2.h"
-#include "xmalloc.h"
-#include "buffer.h"
-#include "bufaux.h"
-#include "packet.h"
-#include "compat.h"
-
-#include <openssl/bn.h>
-#include <openssl/dh.h>
+RCSID("$OpenBSD: kex.c,v 1.23 2001/03/10 17:51:04 markus Exp $");
#include <openssl/crypto.h>
#include <openssl/bio.h>
#include <openssl/dh.h>
#include <openssl/pem.h>
+#include "ssh2.h"
+#include "xmalloc.h"
+#include "buffer.h"
+#include "bufaux.h"
+#include "packet.h"
+#include "compat.h"
+#include "cipher.h"
#include "kex.h"
+#include "key.h"
+#include "log.h"
+#include "mac.h"
+#include "match.h"
#define KEX_COOKIE_LEN 16
kex_init(char *myproposal[PROPOSAL_MAX])
{
int first_kex_packet_follows = 0;
- unsigned char cookie[KEX_COOKIE_LEN];
+ u_char cookie[KEX_COOKIE_LEN];
u_int32_t rand = 0;
int i;
Buffer *ki = xmalloc(sizeof(*ki));
debug("send KEXINIT");
packet_start(SSH2_MSG_KEXINIT);
- packet_put_raw(buffer_ptr(my_kexinit), buffer_len(my_kexinit));
+ packet_put_raw(buffer_ptr(my_kexinit), buffer_len(my_kexinit));
packet_send();
packet_write_wait();
debug("done");
return 0;
}
-DH *
-dh_gen_key(DH *dh)
+void
+dh_gen_key(DH *dh, int need)
{
- int tries = 0;
+ int i, bits_set = 0, tries = 0;
+ if (dh->p == NULL)
+ fatal("dh_gen_key: dh->p == NULL");
+ if (2*need >= BN_num_bits(dh->p))
+ fatal("dh_gen_key: group too small: %d (2*need %d)",
+ BN_num_bits(dh->p), 2*need);
do {
+ if (dh->priv_key != NULL)
+ BN_free(dh->priv_key);
+ dh->priv_key = BN_new();
+ if (dh->priv_key == NULL)
+ fatal("dh_gen_key: BN_new failed");
+ /* generate a 2*need bits random private exponent */
+ if (!BN_rand(dh->priv_key, 2*need, 0, 0))
+ fatal("dh_gen_key: BN_rand failed");
if (DH_generate_key(dh) == 0)
fatal("DH_generate_key");
+ for (i = 0; i <= BN_num_bits(dh->priv_key); i++)
+ if (BN_is_bit_set(dh->priv_key, i))
+ bits_set++;
+ debug("dh_gen_key: priv key bits set: %d/%d",
+ bits_set, BN_num_bits(dh->priv_key));
if (tries++ > 10)
- fatal("dh_new_group1: too many bad keys: giving up");
+ fatal("dh_gen_key: too many bad keys: giving up");
} while (!dh_pub_is_valid(dh, dh->pub_key));
- return dh;
}
DH *
if ((ret = BN_hex2bn(&dh->g, gen)) < 0)
fatal("BN_hex2bn g");
- return (dh_gen_key(dh));
+ return (dh);
}
+/*
+ * This just returns the group, we still need to generate the exchange
+ * value.
+ */
+
DH *
dh_new_group(BIGNUM *gen, BIGNUM *modulus)
{
dh->p = modulus;
dh->g = gen;
- return (dh_gen_key(dh));
+ return (dh);
}
DH *
-dh_new_group1()
+dh_new_group1(void)
{
static char *gen = "2", *group1 =
"FFFFFFFF" "FFFFFFFF" "C90FDAA2" "2168C234" "C4C6628B" "80DC1CD1"
return (dh_new_group_asc(gen, group1));
}
+#ifdef DEBUG_KEX
void
-dump_digest(unsigned char *digest, int len)
+dump_digest(u_char *digest, int len)
{
int i;
for (i = 0; i< len; i++){
}
fprintf(stderr, "\n");
}
+#endif
-unsigned char *
+u_char *
kex_hash(
char *client_version_string,
char *server_version_string,
BIGNUM *shared_secret)
{
Buffer b;
- static unsigned char digest[EVP_MAX_MD_SIZE];
+ static u_char digest[EVP_MAX_MD_SIZE];
EVP_MD *evp_md = EVP_sha1();
EVP_MD_CTX md;
buffer_put_bignum2(&b, client_dh_pub);
buffer_put_bignum2(&b, server_dh_pub);
buffer_put_bignum2(&b, shared_secret);
-
+
#ifdef DEBUG_KEX
buffer_dump(&b);
#endif
return digest;
}
-unsigned char *
+u_char *
kex_hash_gex(
char *client_version_string,
char *server_version_string,
BIGNUM *shared_secret)
{
Buffer b;
- static unsigned char digest[EVP_MAX_MD_SIZE];
+ static u_char digest[EVP_MAX_MD_SIZE];
EVP_MD *evp_md = EVP_sha1();
EVP_MD_CTX md;
buffer_put_bignum2(&b, client_dh_pub);
buffer_put_bignum2(&b, server_dh_pub);
buffer_put_bignum2(&b, shared_secret);
-
+
#ifdef DEBUG_KEX
buffer_dump(&b);
#endif
return digest;
}
-unsigned char *
-derive_key(int id, int need, char unsigned *hash, BIGNUM *shared_secret)
+u_char *
+derive_key(int id, int need, u_char *hash, BIGNUM *shared_secret)
{
Buffer b;
EVP_MD *evp_md = EVP_sha1();
char c = id;
int have;
int mdsz = evp_md->md_size;
- unsigned char *digest = xmalloc(((need+mdsz-1)/mdsz)*mdsz);
+ u_char *digest = xmalloc(((need+mdsz-1)/mdsz)*mdsz);
buffer_init(&b);
buffer_put_bignum2(&b, shared_secret);
return digest;
}
-#define NKEYS 6
-
-#define MAX_PROP 20
-#define SEP ","
-
-char *
-get_match(char *client, char *server)
-{
- char *sproposals[MAX_PROP];
- char *c, *s, *p, *ret, *cp, *sp;
- int i, j, nproposals;
-
- c = cp = xstrdup(client);
- s = sp = xstrdup(server);
-
- for ((p = strsep(&sp, SEP)), i=0; p && *p != '\0';
- (p = strsep(&sp, SEP)), i++) {
- if (i < MAX_PROP)
- sproposals[i] = p;
- else
- break;
- }
- nproposals = i;
-
- for ((p = strsep(&cp, SEP)), i=0; p && *p != '\0';
- (p = strsep(&cp, SEP)), i++) {
- for (j = 0; j < nproposals; j++) {
- if (strcmp(p, sproposals[j]) == 0) {
- ret = xstrdup(p);
- xfree(c);
- xfree(s);
- return ret;
- }
- }
- }
- xfree(c);
- xfree(s);
- return NULL;
-}
void
choose_enc(Enc *enc, char *client, char *server)
{
- char *name = get_match(client, server);
+ char *name = match_list(client, server, NULL);
if (name == NULL)
fatal("no matching cipher found: client %s server %s", client, server);
enc->cipher = cipher_by_name(name);
void
choose_mac(Mac *mac, char *client, char *server)
{
- char *name = get_match(client, server);
+ char *name = match_list(client, server, NULL);
if (name == NULL)
fatal("no matching mac found: client %s server %s", client, server);
- if (strcmp(name, "hmac-md5") == 0) {
- mac->md = EVP_md5();
- } else if (strcmp(name, "hmac-sha1") == 0) {
- mac->md = EVP_sha1();
- } else if (strcmp(name, "hmac-ripemd160@openssh.com") == 0) {
- mac->md = EVP_ripemd160();
- } else {
+ if (mac_init(mac, name) < 0)
fatal("unsupported mac %s", name);
- }
+ /* truncate the key */
+ if (datafellows & SSH_BUG_HMAC)
+ mac->key_len = 16;
mac->name = name;
- mac->mac_len = mac->md->md_size;
- mac->key_len = (datafellows & SSH_BUG_HMAC) ? 16 : mac->mac_len;
mac->key = NULL;
mac->enabled = 0;
}
void
choose_comp(Comp *comp, char *client, char *server)
{
- char *name = get_match(client, server);
+ char *name = match_list(client, server, NULL);
if (name == NULL)
fatal("no matching comp found: client %s server %s", client, server);
if (strcmp(name, "zlib") == 0) {
void
choose_kex(Kex *k, char *client, char *server)
{
- k->name = get_match(client, server);
+ k->name = match_list(client, server, NULL);
if (k->name == NULL)
fatal("no kex alg");
if (strcmp(k->name, KEX_DH1) == 0) {
void
choose_hostkeyalg(Kex *k, char *client, char *server)
{
- k->hostkeyalg = get_match(client, server);
- if (k->hostkeyalg == NULL)
+ char *hostkeyalg = match_list(client, server, NULL);
+ if (hostkeyalg == NULL)
fatal("no hostkey alg");
- if (strcmp(k->hostkeyalg, KEX_DSS) != 0)
- fatal("bad hostkey alg %s", k->hostkeyalg);
+ k->hostkey_type = key_type_from_name(hostkeyalg);
+ if (k->hostkey_type == KEY_UNSPEC)
+ fatal("bad hostkey alg '%s'", hostkeyalg);
+ xfree(hostkeyalg);
}
Kex *
return k;
}
+#define NKEYS 6
int
-kex_derive_keys(Kex *k, unsigned char *hash, BIGNUM *shared_secret)
+kex_derive_keys(Kex *k, u_char *hash, BIGNUM *shared_secret)
{
int i;
int mode;
int ctos;
- unsigned char *keys[NKEYS];
+ u_char *keys[NKEYS];
for (i = 0; i < NKEYS; i++)
keys[i] = derive_key('A'+i, k->we_need, hash, shared_secret);
andersk / openssh.git / blobdiff