upstream commit

switch auth2-hostbased.c to modern APIs; ok djm@

Upstream-ID: 146af25c36daeeb83d5dbbb8ca52b5d25de88f4e
This commit is contained in:
markus@openbsd.org 2017-05-30 14:25:42 +00:00 committed by Damien Miller
parent 2ae666a8fc
commit eb76698b91
1 changed files with 53 additions and 48 deletions

View File

@ -1,4 +1,4 @@
/* $OpenBSD: auth2-hostbased.c,v 1.28 2017/05/30 14:10:53 markus Exp $ */
/* $OpenBSD: auth2-hostbased.c,v 1.29 2017/05/30 14:25:42 markus Exp $ */
/*
* Copyright (c) 2000 Markus Friedl. All rights reserved.
*
@ -39,7 +39,7 @@
#include "misc.h"
#include "servconf.h"
#include "compat.h"
#include "key.h"
#include "sshkey.h"
#include "hostfile.h"
#include "auth.h"
#include "canohost.h"
@ -48,6 +48,7 @@
#endif
#include "monitor_wrap.h"
#include "pathnames.h"
#include "ssherr.h"
#include "match.h"
/* import */
@ -58,52 +59,54 @@ extern u_int session_id2_len;
static int
userauth_hostbased(Authctxt *authctxt)
{
Buffer b;
struct ssh *ssh = active_state; /* XXX */
struct sshbuf *b;
struct sshkey *key = NULL;
char *pkalg, *cuser, *chost, *service;
u_char *pkblob, *sig;
u_int alen, blen, slen;
int pktype;
int authenticated = 0;
size_t alen, blen, slen;
int r, pktype, authenticated = 0;
if (!authctxt->valid) {
debug2("userauth_hostbased: disabled because of invalid user");
debug2("%s: disabled because of invalid user", __func__);
return 0;
}
pkalg = packet_get_string(&alen);
pkblob = packet_get_string(&blen);
chost = packet_get_string(NULL);
cuser = packet_get_string(NULL);
sig = packet_get_string(&slen);
/* XXX use sshkey_froms() */
if ((r = sshpkt_get_cstring(ssh, &pkalg, &alen)) != 0 ||
(r = sshpkt_get_string(ssh, &pkblob, &blen)) != 0 ||
(r = sshpkt_get_cstring(ssh, &chost, NULL)) != 0 ||
(r = sshpkt_get_cstring(ssh, &cuser, NULL)) != 0 ||
(r = sshpkt_get_string(ssh, &sig, &slen)) != 0)
fatal("%s: packet parsing: %s", __func__, ssh_err(r));
debug("userauth_hostbased: cuser %s chost %s pkalg %s slen %d",
debug("%s: cuser %s chost %s pkalg %s slen %zu", __func__,
cuser, chost, pkalg, slen);
#ifdef DEBUG_PK
debug("signature:");
buffer_init(&b);
buffer_append(&b, sig, slen);
buffer_dump(&b);
buffer_free(&b);
sshbuf_dump_data(sig, siglen, stderr);
#endif
pktype = key_type_from_name(pkalg);
pktype = sshkey_type_from_name(pkalg);
if (pktype == KEY_UNSPEC) {
/* this is perfectly legal */
logit("userauth_hostbased: unsupported "
"public key algorithm: %s", pkalg);
logit("%s: unsupported public key algorithm: %s",
__func__, pkalg);
goto done;
}
if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
error("%s: key_from_blob: %s", __func__, ssh_err(r));
goto done;
}
key = key_from_blob(pkblob, blen);
if (key == NULL) {
error("userauth_hostbased: cannot decode key: %s", pkalg);
error("%s: cannot decode key: %s", __func__, pkalg);
goto done;
}
if (key->type != pktype) {
error("userauth_hostbased: type mismatch for decoded key "
"(received %d, expected %d)", key->type, pktype);
error("%s: type mismatch for decoded key "
"(received %d, expected %d)", __func__, key->type, pktype);
goto done;
}
if (key_type_plain(key->type) == KEY_RSA &&
(datafellows & SSH_BUG_RSASIGMD5) != 0) {
if (sshkey_type_plain(key->type) == KEY_RSA &&
(ssh->compat & SSH_BUG_RSASIGMD5) != 0) {
error("Refusing RSA key because peer uses unsafe "
"signature format");
goto done;
@ -115,21 +118,23 @@ userauth_hostbased(Authctxt *authctxt)
goto done;
}
service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
service = ssh->compat & SSH_BUG_HBSERVICE ? "ssh-userauth" :
authctxt->service;
buffer_init(&b);
buffer_put_string(&b, session_id2, session_id2_len);
if ((b = sshbuf_new()) == NULL)
fatal("%s: sshbuf_new failed", __func__);
/* reconstruct packet */
buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
buffer_put_cstring(&b, authctxt->user);
buffer_put_cstring(&b, service);
buffer_put_cstring(&b, "hostbased");
buffer_put_string(&b, pkalg, alen);
buffer_put_string(&b, pkblob, blen);
buffer_put_cstring(&b, chost);
buffer_put_cstring(&b, cuser);
if ((r = sshbuf_put_string(b, session_id2, session_id2_len)) != 0 ||
(r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
(r = sshbuf_put_cstring(b, authctxt->user)) != 0 ||
(r = sshbuf_put_cstring(b, service)) != 0 ||
(r = sshbuf_put_cstring(b, "hostbased")) != 0 ||
(r = sshbuf_put_string(b, pkalg, alen)) != 0 ||
(r = sshbuf_put_string(b, pkblob, blen)) != 0 ||
(r = sshbuf_put_cstring(b, chost)) != 0 ||
(r = sshbuf_put_cstring(b, cuser)) != 0)
fatal("%s: buffer error: %s", __func__, ssh_err(r));
#ifdef DEBUG_PK
buffer_dump(&b);
sshbuf_dump(b, stderr);
#endif
pubkey_auth_info(authctxt, key,
@ -138,15 +143,15 @@ userauth_hostbased(Authctxt *authctxt)
/* test for allowed key and correct signature */
authenticated = 0;
if (PRIVSEP(hostbased_key_allowed(authctxt->pw, cuser, chost, key)) &&
PRIVSEP(sshkey_verify(key, sig, slen, buffer_ptr(&b),
buffer_len(&b), 0)) == 0)
PRIVSEP(sshkey_verify(key, sig, slen,
sshbuf_ptr(b), sshbuf_len(b), ssh->compat)) == 0)
authenticated = 1;
buffer_free(&b);
sshbuf_free(b);
done:
debug2("userauth_hostbased: authenticated %d", authenticated);
debug2("%s: authenticated %d", __func__, authenticated);
if (key != NULL)
key_free(key);
sshkey_free(key);
free(pkalg);
free(pkblob);
free(cuser);
@ -203,8 +208,8 @@ hostbased_key_allowed(struct passwd *pw, const char *cuser, char *chost,
}
debug2("%s: access allowed by auth_rhosts2", __func__);
if (key_is_cert(key) &&
key_cert_check_authority(key, 1, 0, lookup, &reason)) {
if (sshkey_is_cert(key) &&
sshkey_cert_check_authority(key, 1, 0, lookup, &reason)) {
error("%s", reason);
auth_debug_add("%s", reason);
return 0;
@ -223,20 +228,20 @@ hostbased_key_allowed(struct passwd *pw, const char *cuser, char *chost,
}
if (host_status == HOST_OK) {
if (key_is_cert(key)) {
if (sshkey_is_cert(key)) {
if ((fp = sshkey_fingerprint(key->cert->signature_key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
fatal("%s: sshkey_fingerprint fail", __func__);
verbose("Accepted certificate ID \"%s\" signed by "
"%s CA %s from %s@%s", key->cert->key_id,
key_type(key->cert->signature_key), fp,
sshkey_type(key->cert->signature_key), fp,
cuser, lookup);
} else {
if ((fp = sshkey_fingerprint(key,
options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
fatal("%s: sshkey_fingerprint fail", __func__);
verbose("Accepted %s public key %s from %s@%s",
key_type(key), fp, cuser, lookup);
sshkey_type(key), fp, cuser, lookup);
}
free(fp);
}