diff options
Diffstat (limited to 'src/irmd/oap/srv.c')
| -rw-r--r-- | src/irmd/oap/srv.c | 106 |
1 files changed, 90 insertions, 16 deletions
diff --git a/src/irmd/oap/srv.c b/src/irmd/oap/srv.c index 9ace8ed1..aef987eb 100644 --- a/src/irmd/oap/srv.c +++ b/src/irmd/oap/srv.c @@ -146,12 +146,12 @@ static int negotiate_cipher(const struct oap_hdr * peer_hdr, int srv_rank; /* Cipher: select the strongest of client and server */ - cli_nid = peer_hdr->cipher_str != NULL - ? (int) crypt_str_to_nid(peer_hdr->cipher_str) - : NID_undef; + if (peer_hdr->cipher_str != NULL) + cli_nid = (int) crypt_str_to_nid(peer_hdr->cipher_str); + else + cli_nid = NID_undef; - if (cli_nid != NID_undef - && crypt_cipher_rank(cli_nid) < 0) { + if (cli_nid != NID_undef && crypt_cipher_rank(cli_nid) < 0) { log_err_id(id, "Unsupported cipher '%s'.", peer_hdr->cipher_str); return -ENOTSUP; @@ -162,11 +162,9 @@ static int negotiate_cipher(const struct oap_hdr * peer_hdr, if (cli_rank > srv_rank) { SET_KEX_CIPHER_NID(kcfg, cli_nid); - log_dbg_id(id, "Selected client cipher %s.", - kcfg->c.str); + log_dbg_id(id, "Selected client cipher %s.", kcfg->c.str); } else if (srv_rank > 0) { - log_dbg_id(id, "Selected server cipher %s.", - kcfg->c.str); + log_dbg_id(id, "Selected server cipher %s.", kcfg->c.str); } else { log_err_id(id, "Encryption requested, no cipher."); return -ECRYPT; @@ -378,14 +376,24 @@ int oap_srv_process(const struct name_info * info, buffer_t req_buf, buffer_t * rsp_buf, buffer_t * data, - struct crypt_sk * sk) + struct crypt_sk * sk, + bool rekey, + const buffer_t * cached_crt, + buffer_t * peer_crt) { struct oap_hdr peer_hdr; struct oap_hdr local_hdr; struct sec_config kcfg; uint8_t kex_buf[CRYPT_KEY_BUFSZ]; uint8_t hash_buf[MAX_HASH_SIZE]; - buffer_t req_hash = BUF_INIT; + uint8_t kc_buf[MAX_HASH_SIZE]; + uint8_t resp_hash_buf[MAX_HASH_SIZE]; + uint8_t hs_key[SYMMKEYSZ]; + const uint8_t * seal_key = NULL; + buffer_t req_hash = BUF_INIT; + buffer_t resp_hash = BUF_INIT; + buffer_t crt_der = BUF_INIT; + buffer_t rsp_tag = BUF_INIT; ssize_t hash_ret; char cli_name[NAME_SIZE + 1]; uint8_t * id; @@ -412,13 +420,19 @@ int oap_srv_process(const struct name_info * info, goto fail_cred; } + /* Re-key omits the cert; the peer verifies against its cache. */ + if (rekey && crt != NULL) { + crypt_free_crt(crt); + crt = NULL; + } + if (load_srv_kex_config(info, &kcfg) < 0) { log_err("Failed to load KEX config for %s.", info->name); goto fail_kex; } /* Decode incoming header (NID_undef = request, no hash) */ - if (oap_hdr_decode(&peer_hdr, req_buf, NID_undef) < 0) { + if (oap_hdr_decode(&peer_hdr, req_buf, NID_undef, rekey) < 0) { log_err("Failed to decode OAP header."); goto fail_auth; } @@ -439,11 +453,22 @@ int oap_srv_process(const struct name_info * info, oap_hdr_init(&local_hdr, peer_hdr.id, kex_buf, *data, NID_undef); - if (oap_auth_peer(cli_name, &kcfg, &local_hdr, &peer_hdr) < 0) { + if (oap_auth_peer(cli_name, &kcfg, &local_hdr, &peer_hdr, + cached_crt) < 0) { log_err_id(id, "Failed to authenticate client."); goto fail_auth; } + /* Surface the peer cert so the caller can cache it for re-key. */ + if (peer_crt != NULL && peer_hdr.crt.len > 0) { + peer_crt->data = malloc(peer_hdr.crt.len); + if (peer_crt->data == NULL) + goto fail_auth; + + memcpy(peer_crt->data, peer_hdr.crt.data, peer_hdr.crt.len); + peer_crt->len = peer_hdr.crt.len; + } + if (do_server_kex(info, &peer_hdr, &kcfg, &local_hdr.kex, sk) < 0) goto fail_kex; @@ -463,10 +488,58 @@ int oap_srv_process(const struct name_info * info, goto fail_auth; } req_hash.data = hash_buf; - req_hash.len = (size_t) hash_ret; + req_hash.len = (size_t) hash_ret; + + rsp_tag = req_hash; - if (oap_hdr_encode(&local_hdr, pkp, crt, &kcfg, - req_hash, req_md_nid) < 0) { + /* Bind the key to the transcript and confirm it to the client */ + if (sk->nid != NID_undef) { + if (crt != NULL && crypt_crt_der(crt, &crt_der) < 0) { + log_err_id(id, "Failed to serialize cert."); + goto fail_auth; + } + + resp_hash.data = resp_hash_buf; + + ret = oap_resp_hash(req_md_nid, local_hdr.kex, *data, + crt_der, &resp_hash); + + freebuf(crt_der); + + if (ret < 0) { + log_err_id(id, "Failed to hash response."); + goto fail_auth; + } + + /* Derive the identity-seal key before bind mutates sk->key */ + if (oap_derive_hs_key(sk, req_hash, hs_key) < 0) { + log_err_id(id, "Failed to derive handshake key."); + goto fail_auth; + } + + seal_key = hs_key; + + if (oap_bind_session_key(sk, req_hash, resp_hash, + kcfg.k.nid) < 0) { + log_err_id(id, "Failed to bind session key."); + goto fail_auth; + } + + if (oap_key_confirm_tag(sk, req_hash, resp_hash, kc_buf, + (size_t) hash_ret) < 0) { + log_err_id(id, "Failed to confirm session key."); + goto fail_auth; + } + + rsp_tag.data = kc_buf; + } + + ret = oap_hdr_encode(&local_hdr, pkp, crt, &kcfg, + rsp_tag, req_md_nid, seal_key); + + crypt_secure_clear(hs_key, SYMMKEYSZ); + + if (ret < 0) { log_err_id(id, "Failed to create OAP response header."); goto fail_auth; } @@ -491,6 +564,7 @@ int oap_srv_process(const struct name_info * info, fail_data: oap_hdr_fini(&local_hdr); fail_auth: + crypt_secure_clear(hs_key, SYMMKEYSZ); crypt_free_crt(crt); crypt_free_key(pkp); fail_cred: |