diff options
Diffstat (limited to 'kex.c')
| -rw-r--r-- | kex.c | 81 |
1 files changed, 18 insertions, 63 deletions
@@ -1,4 +1,4 @@ -/* $OpenBSD: kex.c,v 1.131 2017/03/15 07:07:39 markus Exp $ */ +/* $OpenBSD: kex.c,v 1.134 2017/06/13 12:13:59 djm Exp $ */ /* * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. * @@ -54,17 +54,9 @@ #include "sshbuf.h" #include "digest.h" -#if OPENSSL_VERSION_NUMBER >= 0x00907000L -# if defined(HAVE_EVP_SHA256) -# define evp_ssh_sha256 EVP_sha256 -# else -extern const EVP_MD *evp_ssh_sha256(void); -# endif -#endif - /* prototype */ static int kex_choose_conf(struct ssh *); -static int kex_input_newkeys(int, u_int32_t, void *); +static int kex_input_newkeys(int, u_int32_t, struct ssh *); static const char *proposal_names[PROPOSAL_MAX] = { "KEX algorithms", @@ -323,9 +315,8 @@ kex_prop_free(char **proposal) /* ARGSUSED */ static int -kex_protocol_error(int type, u_int32_t seq, void *ctxt) +kex_protocol_error(int type, u_int32_t seq, struct ssh *ssh) { - struct ssh *ssh = active_state; /* XXX */ int r; error("kex protocol error: type %d seq %u", type, seq); @@ -383,12 +374,13 @@ kex_send_newkeys(struct ssh *ssh) } int -kex_input_ext_info(int type, u_int32_t seq, void *ctxt) +kex_input_ext_info(int type, u_int32_t seq, struct ssh *ssh) { - struct ssh *ssh = ctxt; struct kex *kex = ssh->kex; u_int32_t i, ninfo; - char *name, *val, *found; + char *name, *found; + u_char *val; + size_t vlen; int r; debug("SSH2_MSG_EXT_INFO received"); @@ -398,12 +390,17 @@ kex_input_ext_info(int type, u_int32_t seq, void *ctxt) for (i = 0; i < ninfo; i++) { if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0) return r; - if ((r = sshpkt_get_cstring(ssh, &val, NULL)) != 0) { + if ((r = sshpkt_get_string(ssh, &val, &vlen)) != 0) { free(name); return r; } - debug("%s: %s=<%s>", __func__, name, val); if (strcmp(name, "server-sig-algs") == 0) { + /* Ensure no \0 lurking in value */ + if (memchr(val, '\0', vlen) != NULL) { + error("%s: nul byte in %s", __func__, name); + return SSH_ERR_INVALID_FORMAT; + } + debug("%s: %s=<%s>", __func__, name, val); found = match_list("rsa-sha2-256", val, NULL); if (found) { kex->rsa_sha2 = 256; @@ -414,7 +411,8 @@ kex_input_ext_info(int type, u_int32_t seq, void *ctxt) kex->rsa_sha2 = 512; free(found); } - } + } else + debug("%s: %s (unrecognised)", __func__, name); free(name); free(val); } @@ -422,9 +420,8 @@ kex_input_ext_info(int type, u_int32_t seq, void *ctxt) } static int -kex_input_newkeys(int type, u_int32_t seq, void *ctxt) +kex_input_newkeys(int type, u_int32_t seq, struct ssh *ssh) { - struct ssh *ssh = ctxt; struct kex *kex = ssh->kex; int r; @@ -475,9 +472,8 @@ kex_send_kexinit(struct ssh *ssh) /* ARGSUSED */ int -kex_input_kexinit(int type, u_int32_t seq, void *ctxt) +kex_input_kexinit(int type, u_int32_t seq, struct ssh *ssh) { - struct ssh *ssh = ctxt; struct kex *kex = ssh->kex; const u_char *ptr; u_int i; @@ -988,47 +984,6 @@ kex_derive_keys_bn(struct ssh *ssh, u_char *hash, u_int hashlen, } #endif -#ifdef WITH_SSH1 -int -derive_ssh1_session_id(BIGNUM *host_modulus, BIGNUM *server_modulus, - u_int8_t cookie[8], u_int8_t id[16]) -{ - u_int8_t hbuf[2048], sbuf[2048], obuf[SSH_DIGEST_MAX_LENGTH]; - struct ssh_digest_ctx *hashctx = NULL; - size_t hlen, slen; - int r; - - hlen = BN_num_bytes(host_modulus); - slen = BN_num_bytes(server_modulus); - if (hlen < (512 / 8) || (u_int)hlen > sizeof(hbuf) || - slen < (512 / 8) || (u_int)slen > sizeof(sbuf)) - return SSH_ERR_KEY_BITS_MISMATCH; - if (BN_bn2bin(host_modulus, hbuf) <= 0 || - BN_bn2bin(server_modulus, sbuf) <= 0) { - r = SSH_ERR_LIBCRYPTO_ERROR; - goto out; - } - if ((hashctx = ssh_digest_start(SSH_DIGEST_MD5)) == NULL) { - r = SSH_ERR_ALLOC_FAIL; - goto out; - } - if (ssh_digest_update(hashctx, hbuf, hlen) != 0 || - ssh_digest_update(hashctx, sbuf, slen) != 0 || - ssh_digest_update(hashctx, cookie, 8) != 0 || - ssh_digest_final(hashctx, obuf, sizeof(obuf)) != 0) { - r = SSH_ERR_LIBCRYPTO_ERROR; - goto out; - } - memcpy(id, obuf, ssh_digest_bytes(SSH_DIGEST_MD5)); - r = 0; - out: - ssh_digest_free(hashctx); - explicit_bzero(hbuf, sizeof(hbuf)); - explicit_bzero(sbuf, sizeof(sbuf)); - explicit_bzero(obuf, sizeof(obuf)); - return r; -} -#endif #if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH) void |