static void
kex_choose_conf(Kex *kex)
{
Newkeys *newkeys;
char **my, **peer;
char **cprop, **sprop;
int nenc, nmac, ncomp;
u_int mode, ctos, need;
int first_kex_follows, type;
int log_flag = 0;
int auth_flag;
auth_flag = packet_authentication_state();
debug ("AUTH STATE IS %d", auth_flag);
my = kex_buf2prop(&kex->my, NULL);
peer = kex_buf2prop(&kex->peer, &first_kex_follows);
if (kex->server) {
cprop=peer;
sprop=my;
} else {
cprop=my;
sprop=peer;
}
/* Check whether server offers roaming */
if (!kex->server) {
char *roaming;
roaming = match_list(KEX_RESUME, peer[PROPOSAL_KEX_ALGS], NULL);
if (roaming) {
kex->roaming = 1;
xfree(roaming);
}
}
/* Algorithm Negotiation */
for (mode = 0; mode < MODE_MAX; mode++) {
newkeys = xcalloc(1, sizeof(*newkeys));
kex->newkeys[mode] = newkeys;
ctos = (!kex->server && mode == MODE_OUT) ||
(kex->server && mode == MODE_IN);
nenc = ctos ? PROPOSAL_ENC_ALGS_CTOS : PROPOSAL_ENC_ALGS_STOC;
nmac = ctos ? PROPOSAL_MAC_ALGS_CTOS : PROPOSAL_MAC_ALGS_STOC;
ncomp = ctos ? PROPOSAL_COMP_ALGS_CTOS : PROPOSAL_COMP_ALGS_STOC;
choose_enc (&newkeys->enc, cprop[nenc], sprop[nenc]);
choose_mac (&newkeys->mac, cprop[nmac], sprop[nmac]);
choose_comp(&newkeys->comp, cprop[ncomp], sprop[ncomp]);
debug("REQUESTED ENC.NAME is '%s'", newkeys->enc.name);
if (strcmp(newkeys->enc.name, "none") == 0) {
debug("Requesting NONE. Authflag is %d", auth_flag);
if (auth_flag == 1) {
debug("None requested post authentication.");
} else {
fatal("Pre-authentication none cipher requests are not allowed.");
}
}
debug("kex: %s %s %s %s",
ctos ? "client->server" : "server->client",
newkeys->enc.name,
newkeys->mac.name,
newkeys->comp.name);
/* client starts withctos = 0 && log flag = 0 and no log*/
/* 2nd client pass ctos=1 and flag = 1 so no log*/
/* server starts with ctos =1 && log_flag = 0 so log */
/* 2nd sever pass ctos = 1 && log flag = 1 so no log*/
/* -cjr*/
if (ctos && !log_flag) {
logit("SSH: Server;Ltype: Kex;Remote: %s-%d;Enc: %s;MAC: %s;Comp: %s",
get_remote_ipaddr(),
get_remote_port(),
newkeys->enc.name,
newkeys->mac.name,
newkeys->comp.name);
}
log_flag = 1;
}
choose_kex(kex, cprop[PROPOSAL_KEX_ALGS], sprop[PROPOSAL_KEX_ALGS]);
choose_hostkeyalg(kex, cprop[PROPOSAL_SERVER_HOST_KEY_ALGS],
sprop[PROPOSAL_SERVER_HOST_KEY_ALGS]);
need = 0;
for (mode = 0; mode < MODE_MAX; mode++) {
newkeys = kex->newkeys[mode];
if (need < newkeys->enc.key_len)
need = newkeys->enc.key_len;
if (need < newkeys->enc.block_size)
need = newkeys->enc.block_size;
if (need < newkeys->mac.key_len)
need = newkeys->mac.key_len;
}
/* XXX need runden? */
kex->we_need = need;
/* ignore the next message if the proposals do not match */
if (first_kex_follows && !proposals_match(my, peer) &&
!(datafellows & SSH_BUG_FIRSTKEX)) {
type = packet_read();
debug2("skipping next packet (type %u)", type);
}
kex_prop_free(my);
kex_prop_free(peer);
}
static void
kex_choose_conf(Kex *kex)
{
Newkeys *newkeys;
char **my, **peer;
char **cprop, **sprop;
int nenc, nmac, ncomp;
u_int mode, ctos, need, dh_need, authlen;
int first_kex_follows, type;
int auth_flag;
auth_flag = packet_authentication_state();
debug ("AUTH STATE IS %d", auth_flag);
my = kex_buf2prop(&kex->my, NULL);
peer = kex_buf2prop(&kex->peer, &first_kex_follows);
if (kex->server) {
cprop=peer;
sprop=my;
} else {
cprop=my;
sprop=peer;
}
/* Check whether server offers roaming */
if (!kex->server) {
char *roaming;
roaming = match_list(KEX_RESUME, peer[PROPOSAL_KEX_ALGS], NULL);
if (roaming) {
kex->roaming = 1;
free(roaming);
}
}
/* Algorithm Negotiation */
for (mode = 0; mode < MODE_MAX; mode++) {
newkeys = xcalloc(1, sizeof(*newkeys));
kex->newkeys[mode] = newkeys;
ctos = (!kex->server && mode == MODE_OUT) ||
(kex->server && mode == MODE_IN);
nenc = ctos ? PROPOSAL_ENC_ALGS_CTOS : PROPOSAL_ENC_ALGS_STOC;
nmac = ctos ? PROPOSAL_MAC_ALGS_CTOS : PROPOSAL_MAC_ALGS_STOC;
ncomp = ctos ? PROPOSAL_COMP_ALGS_CTOS : PROPOSAL_COMP_ALGS_STOC;
choose_enc(&newkeys->enc, cprop[nenc], sprop[nenc]);
/* ignore mac for authenticated encryption */
authlen = cipher_authlen(newkeys->enc.cipher);
if (authlen == 0)
choose_mac(&newkeys->mac, cprop[nmac], sprop[nmac]);
choose_comp(&newkeys->comp, cprop[ncomp], sprop[ncomp]);
debug("REQUESTED ENC.NAME is '%s'", newkeys->enc.name);
if (strcmp(newkeys->enc.name, "none") == 0) {
debug("Requesting NONE. Authflag is %d", auth_flag);
if (auth_flag == 1) {
debug("None requested post authentication.");
} else {
fatal("Pre-authentication none cipher requests are not allowed.");
}
}
debug("kex: %s %s %s %s",
ctos ? "client->server" : "server->client",
newkeys->enc.name,
authlen == 0 ? newkeys->mac.name : "<implicit>",
newkeys->comp.name);
#ifdef NERSC_MOD
if ( ctos ) {
char* t1buf = encode_string(newkeys->enc.name, strlen(newkeys->enc.name));
char* t2buf = encode_string(newkeys->mac.name, strlen(newkeys->mac.name));
char* t3buf = encode_string(newkeys->comp.name, strlen(newkeys->comp.name));
char* t4buf = encode_string(kex->client_version_string, strlen(kex->client_version_string));
s_audit("session_key_exchange", "count=%i uristring=%s_%s_%s_%s",
client_session_id, t4buf, t1buf, t2buf, t3buf);
free(t1buf);
free(t2buf);
free(t3buf);
free(t4buf);
}
#endif
}
choose_kex(kex, cprop[PROPOSAL_KEX_ALGS], sprop[PROPOSAL_KEX_ALGS]);
choose_hostkeyalg(kex, cprop[PROPOSAL_SERVER_HOST_KEY_ALGS],
sprop[PROPOSAL_SERVER_HOST_KEY_ALGS]);
need = dh_need = 0;
for (mode = 0; mode < MODE_MAX; mode++) {
newkeys = kex->newkeys[mode];
need = MAX(need, newkeys->enc.key_len);
need = MAX(need, newkeys->enc.block_size);
need = MAX(need, newkeys->enc.iv_len);
need = MAX(need, newkeys->mac.key_len);
dh_need = MAX(dh_need, cipher_seclen(newkeys->enc.cipher));
dh_need = MAX(dh_need, newkeys->enc.block_size);
dh_need = MAX(dh_need, newkeys->enc.iv_len);
dh_need = MAX(dh_need, newkeys->mac.key_len);
}
/* XXX need runden? */
kex->we_need = need;
kex->dh_need = dh_need;
/* ignore the next message if the proposals do not match */
if (first_kex_follows && !proposals_match(my, peer) &&
!(datafellows & SSH_BUG_FIRSTKEX)) {
type = packet_read();
debug2("skipping next packet (type %u)", type);
}
kex_prop_free(my);
kex_prop_free(peer);
}