int mm_auth_rsa_verify_response(struct sshkey *key, BIGNUM *p, u_char response[16]) { Buffer m; u_char *blob; u_int blen; int r, success = 0; debug3("%s entering", __func__); key->type = KEY_RSA; /* XXX cheat for key_to_blob */ if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) fatal("%s: key_to_blob failed: %s", __func__, ssh_err(r)); key->type = KEY_RSA1; buffer_init(&m); buffer_put_string(&m, blob, blen); buffer_put_string(&m, response, 16); xfree(blob); mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m); mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m); success = buffer_get_int(&m); buffer_free(&m); return (success); }
BIGNUM * mm_auth_rsa_generate_challenge(struct sshkey *key) { Buffer m; BIGNUM *challenge; u_char *blob; u_int blen; int r; debug3("%s entering", __func__); if ((challenge = BN_new()) == NULL) fatal("%s: BN_new failed", __func__); key->type = KEY_RSA; /* XXX cheat for key_to_blob */ if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) fatal("%s: key_to_blob failed: %s", __func__, ssh_err(r)); key->type = KEY_RSA1; buffer_init(&m); buffer_put_string(&m, blob, blen); xfree(blob); mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m); mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m); buffer_get_bignum2(&m, challenge); buffer_free(&m); return (challenge); }
int mm_sshkey_verify(struct sshkey *key, u_char *sig, u_int siglen, u_char *data, u_int datalen, u_int compat) { Buffer m; u_char *blob; u_int len; int r, verified = 0; debug3("%s entering", __func__); /* Convert the key to a blob and the pass it over */ if ((r = sshkey_to_blob(key, &blob, &len)) != 0) { error("%s: sshkey_to_blob failed: %s", __func__, ssh_err(r)); return (0); } buffer_init(&m); buffer_put_string(&m, blob, len); buffer_put_string(&m, sig, siglen); buffer_put_string(&m, data, datalen); xfree(blob); mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m); debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__); mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m); verified = buffer_get_int(&m); buffer_free(&m); return (verified); }
/* ask agent to sign data, returns err.h code on error, 0 on success */ int ssh_agent_sign(int sock, struct sshkey *key, u_char **sigp, size_t *lenp, const u_char *data, size_t datalen, u_int compat) { struct sshbuf *msg; u_char *blob = NULL, type; size_t blen = 0, len = 0; u_int flags = 0; int r = SSH_ERR_INTERNAL_ERROR; if (sigp != NULL) *sigp = NULL; if (lenp != NULL) *lenp = 0; if (datalen > SSH_KEY_MAX_SIGN_DATA_SIZE) return SSH_ERR_INVALID_ARGUMENT; if (compat & SSH_BUG_SIGBLOB) flags |= SSH_AGENT_OLD_SIGNATURE; if ((msg = sshbuf_new()) == NULL) return SSH_ERR_ALLOC_FAIL; if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) goto out; if ((r = sshbuf_put_u8(msg, SSH2_AGENTC_SIGN_REQUEST)) != 0 || (r = sshbuf_put_string(msg, blob, blen)) != 0 || (r = sshbuf_put_string(msg, data, datalen)) != 0 || (r = sshbuf_put_u32(msg, flags)) != 0) goto out; if ((r = ssh_request_reply(sock, msg, msg) != 0)) goto out; if ((r = sshbuf_get_u8(msg, &type)) != 0) goto out; if (agent_failed(type)) { r = SSH_ERR_AGENT_FAILURE; goto out; } else if (type != SSH2_AGENT_SIGN_RESPONSE) { r = SSH_ERR_INVALID_FORMAT; goto out; } if ((r = sshbuf_get_string(msg, sigp, &len)) != 0) goto out; *lenp = len; r = 0; out: if (blob != NULL) { explicit_bzero(blob, blen); free(blob); } sshbuf_free(msg); return r; }
int mm_answer_rsa_keyallowed(int sock, struct sshbuf *m) { BIGNUM *client_n; struct sshkey *key = NULL; u_char *blob = NULL; size_t blen = 0; int r, allowed = 0; debug3("%s entering", __func__); auth_method = "rsa"; if (options.rsa_authentication && authctxt->valid) { if ((client_n = BN_new()) == NULL) fatal("%s: BN_new", __func__); if ((r = sshbuf_get_bignum2(m, client_n)) != 0) fatal("%s: buffer error: %s", __func__, ssh_err(r)); allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key); BN_clear_free(client_n); } sshbuf_reset(m); if ((r = sshbuf_put_u32(m, allowed)) != 0 || (r = sshbuf_put_u32(m, forced_command != NULL)) != 0) fatal("%s: buffer error: %s", __func__, ssh_err(r)); /* clear temporarily storage (used by generate challenge) */ monitor_reset_key_state(); if (allowed && key != NULL) { key->type = KEY_RSA; /* cheat for key_to_blob */ if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) fatal("%s: key_to_blob failed: %s", __func__, ssh_err(r)); if ((r = sshbuf_put_string(m, blob, blen)) != 0) fatal("%s: buffer error: %s", __func__, ssh_err(r)); /* Save temporarily for comparison in verify */ key_blob = blob; key_bloblen = blen; key_blobtype = MM_RSAUSERKEY; } if (key != NULL) sshkey_free(key); mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m); monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed); monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0); return (0); }
/* * Removes an identity from the authentication server. * This call is intended only for use by ssh-add(1) and like applications. */ int ssh_remove_identity(int sock, struct sshkey *key) { struct sshbuf *msg; int r; u_char type, *blob = NULL; size_t blen; if ((msg = sshbuf_new()) == NULL) return SSH_ERR_ALLOC_FAIL; #ifdef WITH_SSH1 if (key->type == KEY_RSA1) { if ((r = sshbuf_put_u8(msg, SSH_AGENTC_REMOVE_RSA_IDENTITY)) != 0 || (r = sshbuf_put_u32(msg, BN_num_bits(key->rsa->n))) != 0 || (r = sshbuf_put_bignum1(msg, key->rsa->e)) != 0 || (r = sshbuf_put_bignum1(msg, key->rsa->n)) != 0) goto out; } else #endif if (key->type != KEY_UNSPEC) { if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) goto out; if ((r = sshbuf_put_u8(msg, SSH2_AGENTC_REMOVE_IDENTITY)) != 0 || (r = sshbuf_put_string(msg, blob, blen)) != 0) goto out; } else { r = SSH_ERR_INVALID_ARGUMENT; goto out; } if ((r = ssh_request_reply(sock, msg, msg)) != 0) goto out; if ((r = sshbuf_get_u8(msg, &type)) != 0) goto out; r = decode_reply(type); out: if (blob != NULL) { explicit_bzero(blob, blen); free(blob); } sshbuf_free(msg); return r; }
static int pkcs11_rsa_private_encrypt(int flen, const u_char *from, u_char *to, RSA *rsa, int padding) { struct sshkey key; u_char *blob, *signature = NULL; size_t blen, slen = 0; int r, ret = -1; struct sshbuf *msg; if (padding != RSA_PKCS1_PADDING) return (-1); key.type = KEY_RSA; key.rsa = rsa; if ((r = sshkey_to_blob(&key, &blob, &blen)) != 0) { error("%s: sshkey_to_blob: %s", __func__, ssh_err(r)); return -1; } if ((msg = sshbuf_new()) == NULL) fatal("%s: sshbuf_new failed", __func__); if ((r = sshbuf_put_u8(msg, SSH2_AGENTC_SIGN_REQUEST)) != 0 || (r = sshbuf_put_string(msg, blob, blen)) != 0 || (r = sshbuf_put_string(msg, from, flen)) != 0 || (r = sshbuf_put_u32(msg, 0)) != 0) fatal("%s: buffer error: %s", __func__, ssh_err(r)); xfree(blob); send_msg(msg); sshbuf_reset(msg); if (recv_msg(msg) == SSH2_AGENT_SIGN_RESPONSE) { if ((r = sshbuf_get_string(msg, &signature, &slen)) != 0) fatal("%s: buffer error: %s", __func__, ssh_err(r)); if (slen <= (size_t)RSA_size(rsa)) { memcpy(to, signature, slen); ret = slen; } xfree(signature); } sshbuf_free(msg); return (ret); }
int mm_key_allowed(enum mm_keytype type, char *user, char *host, struct sshkey *key) { Buffer m; u_char *blob; u_int len; int r, allowed = 0, have_forced = 0; debug3("%s entering", __func__); /* Convert the key to a blob and the pass it over */ if ((r = sshkey_to_blob(key, &blob, &len)) != 0) { error("%s: key_to_blob: %s", __func__, ssh_err(r)); return (0); } buffer_init(&m); buffer_put_int(&m, type); buffer_put_cstring(&m, user ? user : ""); buffer_put_cstring(&m, host ? host : ""); buffer_put_string(&m, blob, len); xfree(blob); mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m); debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__); mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m); allowed = buffer_get_int(&m); /* fake forced command */ auth_clear_options(); have_forced = buffer_get_int(&m); forced_command = have_forced ? xstrdup("true") : NULL; buffer_free(&m); return (allowed); }
int key_to_blob(const Key *key, u_char **blobp, u_int *lenp) { u_char *blob; size_t blen; int r; if (blobp != NULL) *blobp = NULL; if (lenp != NULL) *lenp = 0; if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) { fatal_on_fatal_errors(r, __func__, 0); error("%s: %s", __func__, ssh_err(r)); return 0; } if (blen > INT_MAX) fatal("%s: giant len %zu", __func__, blen); if (blobp != NULL) *blobp = blob; if (lenp != NULL) *lenp = blen; return blen; }
static int input_kex_ecdh_init(int type, u_int32_t seq, struct ssh *ssh) { struct kex *kex = ssh->kex; EC_POINT *client_public; EC_KEY *server_key = NULL; const EC_GROUP *group; const EC_POINT *public_key; BIGNUM *shared_secret = NULL; struct sshkey *server_host_private, *server_host_public; u_char *server_host_key_blob = NULL, *signature = NULL; u_char *kbuf = NULL; u_char hash[SSH_DIGEST_MAX_LENGTH]; size_t slen, sbloblen; size_t klen = 0, hashlen; int r; if ((server_key = EC_KEY_new_by_curve_name(kex->ec_nid)) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if (EC_KEY_generate_key(server_key) != 1) { r = SSH_ERR_LIBCRYPTO_ERROR; goto out; } group = EC_KEY_get0_group(server_key); #ifdef DEBUG_KEXECDH fputs("server private key:\n", stderr); sshkey_dump_ec_key(server_key); #endif if (kex->load_host_public_key == NULL || kex->load_host_private_key == NULL) { r = SSH_ERR_INVALID_ARGUMENT; goto out; } server_host_public = kex->load_host_public_key(kex->hostkey_type, kex->hostkey_nid, ssh); server_host_private = kex->load_host_private_key(kex->hostkey_type, kex->hostkey_nid, ssh); if (server_host_public == NULL) { r = SSH_ERR_NO_HOSTKEY_LOADED; goto out; } if ((client_public = EC_POINT_new(group)) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if ((r = sshpkt_get_ec(ssh, client_public, group)) != 0 || (r = sshpkt_get_end(ssh)) != 0) goto out; #ifdef DEBUG_KEXECDH fputs("client public key:\n", stderr); sshkey_dump_ec_point(group, client_public); #endif if (sshkey_ec_validate_public(group, client_public) != 0) { sshpkt_disconnect(ssh, "invalid client public key"); r = SSH_ERR_MESSAGE_INCOMPLETE; goto out; } /* Calculate shared_secret */ klen = (EC_GROUP_get_degree(group) + 7) / 8; if ((kbuf = malloc(klen)) == NULL || (shared_secret = BN_new()) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if (ECDH_compute_key(kbuf, klen, client_public, server_key, NULL) != (int)klen || BN_bin2bn(kbuf, klen, shared_secret) == NULL) { r = SSH_ERR_LIBCRYPTO_ERROR; goto out; } #ifdef DEBUG_KEXECDH dump_digest("shared secret", kbuf, klen); #endif /* calc H */ if ((r = sshkey_to_blob(server_host_public, &server_host_key_blob, &sbloblen)) != 0) goto out; hashlen = sizeof(hash); if ((r = kex_ecdh_hash( kex->hash_alg, group, kex->client_version_string, kex->server_version_string, sshbuf_ptr(kex->peer), sshbuf_len(kex->peer), sshbuf_ptr(kex->my), sshbuf_len(kex->my), server_host_key_blob, sbloblen, client_public, EC_KEY_get0_public_key(server_key), shared_secret, hash, &hashlen)) != 0) goto out; /* save session id := H */ if (kex->session_id == NULL) { kex->session_id_len = hashlen; kex->session_id = malloc(kex->session_id_len); if (kex->session_id == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } memcpy(kex->session_id, hash, kex->session_id_len); } /* sign H */ if ((r = kex->sign(server_host_private, server_host_public, &signature, &slen, hash, hashlen, kex->hostkey_alg, ssh->compat)) < 0) goto out; /* destroy_sensitive_data(); */ public_key = EC_KEY_get0_public_key(server_key); /* send server hostkey, ECDH pubkey 'Q_S' and signed H */ if ((r = sshpkt_start(ssh, SSH2_MSG_KEX_ECDH_REPLY)) != 0 || (r = sshpkt_put_string(ssh, server_host_key_blob, sbloblen)) != 0 || (r = sshpkt_put_ec(ssh, public_key, group)) != 0 || (r = sshpkt_put_string(ssh, signature, slen)) != 0 || (r = sshpkt_send(ssh)) != 0) goto out; if ((r = kex_derive_keys_bn(ssh, hash, hashlen, shared_secret)) == 0) r = kex_send_newkeys(ssh); out: explicit_bzero(hash, sizeof(hash)); if (kex->ec_client_key) { EC_KEY_free(kex->ec_client_key); kex->ec_client_key = NULL; } if (server_key) EC_KEY_free(server_key); if (kbuf) { explicit_bzero(kbuf, klen); free(kbuf); } if (shared_secret) BN_clear_free(shared_secret); free(server_host_key_blob); free(signature); return r; }
static int input_kex_c25519_init(int type, u_int32_t seq, struct ssh *ssh) { struct kex *kex = ssh->kex; struct sshkey *server_host_private, *server_host_public; struct sshbuf *shared_secret = NULL; u_char *server_host_key_blob = NULL, *signature = NULL; u_char server_key[CURVE25519_SIZE]; u_char *client_pubkey = NULL; u_char server_pubkey[CURVE25519_SIZE]; u_char hash[SSH_DIGEST_MAX_LENGTH]; size_t slen, pklen, sbloblen, hashlen; int r; /* generate private key */ kexc25519_keygen(server_key, server_pubkey); #ifdef DEBUG_KEXECDH dump_digest("server private key:", server_key, sizeof(server_key)); #endif if (kex->load_host_public_key == NULL || kex->load_host_private_key == NULL) { r = SSH_ERR_INVALID_ARGUMENT; goto out; } server_host_public = kex->load_host_public_key(kex->hostkey_type, kex->hostkey_nid, ssh); server_host_private = kex->load_host_private_key(kex->hostkey_type, kex->hostkey_nid, ssh); if (server_host_public == NULL) { r = SSH_ERR_NO_HOSTKEY_LOADED; goto out; } if ((r = sshpkt_get_string(ssh, &client_pubkey, &pklen)) != 0 || (r = sshpkt_get_end(ssh)) != 0) goto out; if (pklen != CURVE25519_SIZE) { r = SSH_ERR_SIGNATURE_INVALID; goto out; } #ifdef DEBUG_KEXECDH dump_digest("client public key:", client_pubkey, CURVE25519_SIZE); #endif if ((shared_secret = sshbuf_new()) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if ((r = kexc25519_shared_key(server_key, client_pubkey, shared_secret)) < 0) goto out; /* calc H */ if ((r = sshkey_to_blob(server_host_public, &server_host_key_blob, &sbloblen)) != 0) goto out; hashlen = sizeof(hash); if ((r = kex_c25519_hash( kex->hash_alg, kex->client_version_string, kex->server_version_string, sshbuf_ptr(kex->peer), sshbuf_len(kex->peer), sshbuf_ptr(kex->my), sshbuf_len(kex->my), server_host_key_blob, sbloblen, client_pubkey, server_pubkey, sshbuf_ptr(shared_secret), sshbuf_len(shared_secret), hash, &hashlen)) < 0) goto out; /* save session id := H */ if (kex->session_id == NULL) { kex->session_id_len = hashlen; kex->session_id = malloc(kex->session_id_len); if (kex->session_id == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } memcpy(kex->session_id, hash, kex->session_id_len); } /* sign H */ if ((r = kex->sign(server_host_private, server_host_public, &signature, &slen, hash, hashlen, kex->hostkey_alg, ssh->compat)) < 0) goto out; /* send server hostkey, ECDH pubkey 'Q_S' and signed H */ if ((r = sshpkt_start(ssh, SSH2_MSG_KEX_ECDH_REPLY)) != 0 || (r = sshpkt_put_string(ssh, server_host_key_blob, sbloblen)) != 0 || (r = sshpkt_put_string(ssh, server_pubkey, sizeof(server_pubkey))) != 0 || (r = sshpkt_put_string(ssh, signature, slen)) != 0 || (r = sshpkt_send(ssh)) != 0) goto out; if ((r = kex_derive_keys(ssh, hash, hashlen, shared_secret)) == 0) r = kex_send_newkeys(ssh); out: explicit_bzero(hash, sizeof(hash)); explicit_bzero(server_key, sizeof(server_key)); free(server_host_key_blob); free(signature); free(client_pubkey); sshbuf_free(shared_secret); return r; }
int input_kex_dh_init(int type, u_int32_t seq, void *ctxt) { struct ssh *ssh = ctxt; struct kex *kex = ssh->kex; BIGNUM *shared_secret = NULL, *dh_client_pub = NULL; struct sshkey *server_host_public, *server_host_private; u_char *kbuf = NULL, *signature = NULL, *server_host_key_blob = NULL; u_char hash[SSH_DIGEST_MAX_LENGTH]; size_t sbloblen, slen; size_t klen = 0, hashlen; int kout, r; if (kex->load_host_public_key == NULL || kex->load_host_private_key == NULL) { r = SSH_ERR_INVALID_ARGUMENT; goto out; } server_host_public = kex->load_host_public_key(kex->hostkey_type, kex->hostkey_nid, ssh); server_host_private = kex->load_host_private_key(kex->hostkey_type, kex->hostkey_nid, ssh); if (server_host_public == NULL) { r = SSH_ERR_NO_HOSTKEY_LOADED; goto out; } /* key, cert */ if ((dh_client_pub = BN_new()) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if ((r = sshpkt_get_bignum2(ssh, dh_client_pub)) != 0 || (r = sshpkt_get_end(ssh)) != 0) goto out; #ifdef DEBUG_KEXDH fprintf(stderr, "dh_client_pub= "); BN_print_fp(stderr, dh_client_pub); fprintf(stderr, "\n"); debug("bits %d", BN_num_bits(dh_client_pub)); #endif #ifdef DEBUG_KEXDH DHparams_print_fp(stderr, kex->dh); fprintf(stderr, "pub= "); BN_print_fp(stderr, kex->dh->pub_key); fprintf(stderr, "\n"); #endif if (!dh_pub_is_valid(kex->dh, dh_client_pub)) { sshpkt_disconnect(ssh, "bad client public DH value"); r = SSH_ERR_MESSAGE_INCOMPLETE; goto out; } klen = DH_size(kex->dh); if ((kbuf = malloc(klen)) == NULL || (shared_secret = BN_new()) == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } if ((kout = DH_compute_key(kbuf, dh_client_pub, kex->dh)) < 0 || BN_bin2bn(kbuf, kout, shared_secret) == NULL) { r = SSH_ERR_LIBCRYPTO_ERROR; goto out; } #ifdef DEBUG_KEXDH dump_digest("shared secret", kbuf, kout); #endif if ((r = sshkey_to_blob(server_host_public, &server_host_key_blob, &sbloblen)) != 0) goto out; /* calc H */ hashlen = sizeof(hash); if ((r = kex_dh_hash( kex->client_version_string, kex->server_version_string, sshbuf_ptr(kex->peer), sshbuf_len(kex->peer), sshbuf_ptr(kex->my), sshbuf_len(kex->my), server_host_key_blob, sbloblen, dh_client_pub, kex->dh->pub_key, shared_secret, hash, &hashlen)) != 0) goto out; /* save session id := H */ if (kex->session_id == NULL) { kex->session_id_len = hashlen; kex->session_id = malloc(kex->session_id_len); if (kex->session_id == NULL) { r = SSH_ERR_ALLOC_FAIL; goto out; } memcpy(kex->session_id, hash, kex->session_id_len); } /* sign H */ if ((r = kex->sign(server_host_private, server_host_public, &signature, &slen, hash, hashlen, kex->hostkey_alg, ssh->compat)) < 0) goto out; /* destroy_sensitive_data(); */ /* send server hostkey, DH pubkey 'f' and singed H */ if ((r = sshpkt_start(ssh, SSH2_MSG_KEXDH_REPLY)) != 0 || (r = sshpkt_put_string(ssh, server_host_key_blob, sbloblen)) != 0 || (r = sshpkt_put_bignum2(ssh, kex->dh->pub_key)) != 0 || /* f */ (r = sshpkt_put_string(ssh, signature, slen)) != 0 || (r = sshpkt_send(ssh)) != 0) goto out; if ((r = kex_derive_keys_bn(ssh, hash, hashlen, shared_secret)) == 0) r = kex_send_newkeys(ssh); out: explicit_bzero(hash, sizeof(hash)); DH_free(kex->dh); kex->dh = NULL; if (dh_client_pub) BN_clear_free(dh_client_pub); if (kbuf) { explicit_bzero(kbuf, klen); free(kbuf); } if (shared_secret) BN_clear_free(shared_secret); free(server_host_key_blob); free(signature); return r; }