// SPDX-License-Identifier: GPL-2.0 #include #include #include #include #include #include #include #include #include #include "crypto.h" #include "auth_x.h" #include "auth_x_protocol.h" static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed); static int ceph_x_is_authenticated(struct ceph_auth_client *ac) { struct ceph_x_info *xi = ac->private; int need; ceph_x_validate_tickets(ac, &need); dout("ceph_x_is_authenticated want=%d need=%d have=%d\n", ac->want_keys, need, xi->have_keys); return (ac->want_keys & xi->have_keys) == ac->want_keys; } static int ceph_x_should_authenticate(struct ceph_auth_client *ac) { struct ceph_x_info *xi = ac->private; int need; ceph_x_validate_tickets(ac, &need); dout("ceph_x_should_authenticate want=%d need=%d have=%d\n", ac->want_keys, need, xi->have_keys); return need != 0; } static int ceph_x_encrypt_offset(void) { return sizeof(u32) + sizeof(struct ceph_x_encrypt_header); } static int ceph_x_encrypt_buflen(int ilen) { return ceph_x_encrypt_offset() + ilen + 16; } static int ceph_x_encrypt(struct ceph_crypto_key *secret, void *buf, int buf_len, int plaintext_len) { struct ceph_x_encrypt_header *hdr = buf + sizeof(u32); int ciphertext_len; int ret; hdr->struct_v = 1; hdr->magic = cpu_to_le64(CEPHX_ENC_MAGIC); ret = ceph_crypt(secret, true, buf + sizeof(u32), buf_len - sizeof(u32), plaintext_len + sizeof(struct ceph_x_encrypt_header), &ciphertext_len); if (ret) return ret; ceph_encode_32(&buf, ciphertext_len); return sizeof(u32) + ciphertext_len; } static int ceph_x_decrypt(struct ceph_crypto_key *secret, void **p, void *end) { struct ceph_x_encrypt_header *hdr = *p + sizeof(u32); int ciphertext_len, plaintext_len; int ret; ceph_decode_32_safe(p, end, ciphertext_len, e_inval); ceph_decode_need(p, end, ciphertext_len, e_inval); ret = ceph_crypt(secret, false, *p, end - *p, ciphertext_len, &plaintext_len); if (ret) return ret; if (hdr->struct_v != 1 || le64_to_cpu(hdr->magic) != CEPHX_ENC_MAGIC) return -EPERM; *p += ciphertext_len; return plaintext_len - sizeof(struct ceph_x_encrypt_header); e_inval: return -EINVAL; } /* * get existing (or insert new) ticket handler */ static struct ceph_x_ticket_handler * get_ticket_handler(struct ceph_auth_client *ac, int service) { struct ceph_x_ticket_handler *th; struct ceph_x_info *xi = ac->private; struct rb_node *parent = NULL, **p = &xi->ticket_handlers.rb_node; while (*p) { parent = *p; th = rb_entry(parent, struct ceph_x_ticket_handler, node); if (service < th->service) p = &(*p)->rb_left; else if (service > th->service) p = &(*p)->rb_right; else return th; } /* add it */ th = kzalloc(sizeof(*th), GFP_NOFS); if (!th) return ERR_PTR(-ENOMEM); th->service = service; rb_link_node(&th->node, parent, p); rb_insert_color(&th->node, &xi->ticket_handlers); return th; } static void remove_ticket_handler(struct ceph_auth_client *ac, struct ceph_x_ticket_handler *th) { struct ceph_x_info *xi = ac->private; dout("remove_ticket_handler %p %d\n", th, th->service); rb_erase(&th->node, &xi->ticket_handlers); ceph_crypto_key_destroy(&th->session_key); if (th->ticket_blob) ceph_buffer_put(th->ticket_blob); kfree(th); } static int process_one_ticket(struct ceph_auth_client *ac, struct ceph_crypto_key *secret, void **p, void *end) { struct ceph_x_info *xi = ac->private; int type; u8 tkt_struct_v, blob_struct_v; struct ceph_x_ticket_handler *th; void *dp, *dend; int dlen; char is_enc; struct timespec64 validity; void *tp, *tpend; void **ptp; struct ceph_crypto_key new_session_key = { 0 }; struct ceph_buffer *new_ticket_blob; time64_t new_expires, new_renew_after; u64 new_secret_id; int ret; ceph_decode_need(p, end, sizeof(u32) + 1, bad); type = ceph_decode_32(p); dout(" ticket type %d %s\n", type, ceph_entity_type_name(type)); tkt_struct_v = ceph_decode_8(p); if (tkt_struct_v != 1) goto bad; th = get_ticket_handler(ac, type); if (IS_ERR(th)) { ret = PTR_ERR(th); goto out; } /* blob for me */ dp = *p + ceph_x_encrypt_offset(); ret = ceph_x_decrypt(secret, p, end); if (ret < 0) goto out; dout(" decrypted %d bytes\n", ret); dend = dp + ret; tkt_struct_v = ceph_decode_8(&dp); if (tkt_struct_v != 1) goto bad; ret = ceph_crypto_key_decode(&new_session_key, &dp, dend); if (ret) goto out; ceph_decode_timespec64(&validity, dp); dp += sizeof(struct ceph_timespec); new_expires = ktime_get_real_seconds() + validity.tv_sec; new_renew_after = new_expires - (validity.tv_sec / 4); dout(" expires=%llu renew_after=%llu\n", new_expires, new_renew_after); /* ticket blob for service */ ceph_decode_8_safe(p, end, is_enc, bad); if (is_enc) { /* encrypted */ tp = *p + ceph_x_encrypt_offset(); ret = ceph_x_decrypt(&th->session_key, p, end); if (ret < 0) goto out; dout(" encrypted ticket, decrypted %d bytes\n", ret); ptp = &tp; tpend = tp + ret; } else { /* unencrypted */ ptp = p; tpend = end; } ceph_decode_32_safe(ptp, tpend, dlen, bad); dout(" ticket blob is %d bytes\n", dlen); ceph_decode_need(ptp, tpend, 1 + sizeof(u64), bad); blob_struct_v = ceph_decode_8(ptp); if (blob_struct_v != 1) goto bad; new_secret_id = ceph_decode_64(ptp); ret = ceph_decode_buffer(&new_ticket_blob, ptp, tpend); if (ret) goto out; /* all is well, update our ticket */ ceph_crypto_key_destroy(&th->session_key); if (th->ticket_blob) ceph_buffer_put(th->ticket_blob); th->session_key = new_session_key; th->ticket_blob = new_ticket_blob; th->secret_id = new_secret_id; th->expires = new_expires; th->renew_after = new_renew_after; th->have_key = true; dout(" got ticket service %d (%s) secret_id %lld len %d\n", type, ceph_entity_type_name(type), th->secret_id, (int)th->ticket_blob->vec.iov_len); xi->have_keys |= th->service; return 0; bad: ret = -EINVAL; out: ceph_crypto_key_destroy(&new_session_key); return ret; } static int ceph_x_proc_ticket_reply(struct ceph_auth_client *ac, struct ceph_crypto_key *secret, void *buf, void *end) { void *p = buf; u8 reply_struct_v; u32 num; int ret; ceph_decode_8_safe(&p, end, reply_struct_v, bad); if (reply_struct_v != 1) return -EINVAL; ceph_decode_32_safe(&p, end, num, bad); dout("%d tickets\n", num); while (num--) { ret = process_one_ticket(ac, secret, &p, end); if (ret) return ret; } return 0; bad: return -EINVAL; } static void ceph_x_authorizer_cleanup(struct ceph_x_authorizer *au) { ceph_crypto_key_destroy(&au->session_key); if (au->buf) { ceph_buffer_put(au->buf); au->buf = NULL; } } static int ceph_x_build_authorizer(struct ceph_auth_client *ac, struct ceph_x_ticket_handler *th, struct ceph_x_authorizer *au) { int maxlen; struct ceph_x_authorize_a *msg_a; struct ceph_x_authorize_b *msg_b; void *p, *end; int ret; int ticket_blob_len = (th->ticket_blob ? th->ticket_blob->vec.iov_len : 0); dout("build_authorizer for %s %p\n", ceph_entity_type_name(th->service), au); ceph_crypto_key_destroy(&au->session_key); ret = ceph_crypto_key_clone(&au->session_key, &th->session_key); if (ret) goto out_au; maxlen = sizeof(*msg_a) + ticket_blob_len + ceph_x_encrypt_buflen(sizeof(*msg_b)); dout(" need len %d\n", maxlen); if (au->buf && au->buf->alloc_len < maxlen) { ceph_buffer_put(au->buf); au->buf = NULL; } if (!au->buf) { au->buf = ceph_buffer_new(maxlen, GFP_NOFS); if (!au->buf) { ret = -ENOMEM; goto out_au; } } au->service = th->service; au->secret_id = th->secret_id; msg_a = au->buf->vec.iov_base; msg_a->struct_v = 1; msg_a->global_id = cpu_to_le64(ac->global_id); msg_a->service_id = cpu_to_le32(th->service); msg_a->ticket_blob.struct_v = 1; msg_a->ticket_blob.secret_id = cpu_to_le64(th->secret_id); msg_a->ticket_blob.blob_len = cpu_to_le32(ticket_blob_len); if (ticket_blob_len) { memcpy(msg_a->ticket_blob.blob, th->ticket_blob->vec.iov_base, th->ticket_blob->vec.iov_len); } dout(" th %p secret_id %lld %lld\n", th, th->secret_id, le64_to_cpu(msg_a->ticket_blob.secret_id)); p = msg_a + 1; p += ticket_blob_len; end = au->buf->vec.iov_base + au->buf->vec.iov_len; msg_b = p + ceph_x_encrypt_offset(); msg_b->struct_v = 1; get_random_bytes(&au->nonce, sizeof(au->nonce)); msg_b->nonce = cpu_to_le64(au->nonce); ret = ceph_x_encrypt(&au->session_key, p, end - p, sizeof(*msg_b)); if (ret < 0) goto out_au; p += ret; WARN_ON(p > end); au->buf->vec.iov_len = p - au->buf->vec.iov_base; dout(" built authorizer nonce %llx len %d\n", au->nonce, (int)au->buf->vec.iov_len); return 0; out_au: ceph_x_authorizer_cleanup(au); return ret; } static int ceph_x_encode_ticket(struct ceph_x_ticket_handler *th, void **p, void *end) { ceph_decode_need(p, end, 1 + sizeof(u64), bad); ceph_encode_8(p, 1); ceph_encode_64(p, th->secret_id); if (th->ticket_blob) { const char *buf = th->ticket_blob->vec.iov_base; u32 len = th->ticket_blob->vec.iov_len; ceph_encode_32_safe(p, end, len, bad); ceph_encode_copy_safe(p, end, buf, len, bad); } else { ceph_encode_32_safe(p, end, 0, bad); } return 0; bad: return -ERANGE; } static bool need_key(struct ceph_x_ticket_handler *th) { if (!th->have_key) return true; return ktime_get_real_seconds() >= th->renew_after; } static bool have_key(struct ceph_x_ticket_handler *th) { if (th->have_key) { if (ktime_get_real_seconds() >= th->expires) th->have_key = false; } return th->have_key; } static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed) { int want = ac->want_keys; struct ceph_x_info *xi = ac->private; int service; *pneed = ac->want_keys & ~(xi->have_keys); for (service = 1; service <= want; service <<= 1) { struct ceph_x_ticket_handler *th; if (!(ac->want_keys & service)) continue; if (*pneed & service) continue; th = get_ticket_handler(ac, service); if (IS_ERR(th)) { *pneed |= service; continue; } if (need_key(th)) *pneed |= service; if (!have_key(th)) xi->have_keys &= ~service; } } static int ceph_x_build_request(struct ceph_auth_client *ac, void *buf, void *end) { struct ceph_x_info *xi = ac->private; int need; struct ceph_x_request_header *head = buf; int ret; struct ceph_x_ticket_handler *th = get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH); if (IS_ERR(th)) return PTR_ERR(th); ceph_x_validate_tickets(ac, &need); dout("build_request want %x have %x need %x\n", ac->want_keys, xi->have_keys, need); if (need & CEPH_ENTITY_TYPE_AUTH) { struct ceph_x_authenticate *auth = (void *)(head + 1); void *p = auth + 1; void *enc_buf = xi->auth_authorizer.enc_buf; struct ceph_x_challenge_blob *blob = enc_buf + ceph_x_encrypt_offset(); u64 *u; if (p > end) return -ERANGE; dout(" get_auth_session_key\n"); head->op = cpu_to_le16(CEPHX_GET_AUTH_SESSION_KEY); /* encrypt and hash */ get_random_bytes(&auth->client_challenge, sizeof(u64)); blob->client_challenge = auth->client_challenge; blob->server_challenge = cpu_to_le64(xi->server_challenge); ret = ceph_x_encrypt(&xi->secret, enc_buf, CEPHX_AU_ENC_BUF_LEN, sizeof(*blob)); if (ret < 0) return ret; auth->struct_v = 1; auth->key = 0; for (u = (u64 *)enc_buf; u + 1 <= (u64 *)(enc_buf + ret); u++) auth->key ^= *(__le64 *)u; dout(" server_challenge %llx client_challenge %llx key %llx\n", xi->server_challenge, le64_to_cpu(auth->client_challenge), le64_to_cpu(auth->key)); /* now encode the old ticket if exists */ ret = ceph_x_encode_ticket(th, &p, end); if (ret < 0) return ret; return p - buf; } if (need) { void *p = head + 1; struct ceph_x_service_ticket_request *req; if (p > end) return -ERANGE; head->op = cpu_to_le16(CEPHX_GET_PRINCIPAL_SESSION_KEY); ret = ceph_x_build_authorizer(ac, th, &xi->auth_authorizer); if (ret) return ret; ceph_encode_copy(&p, xi->auth_authorizer.buf->vec.iov_base, xi->auth_authorizer.buf->vec.iov_len); req = p; req->keys = cpu_to_le32(need); p += sizeof(*req); return p - buf; } return 0; } static int ceph_x_handle_reply(struct ceph_auth_client *ac, int result, void *buf, void *end) { struct ceph_x_info *xi = ac->private; struct ceph_x_reply_header *head = buf; struct ceph_x_ticket_handler *th; int len = end - buf; int op; int ret; if (result) return result; /* XXX hmm? */ if (xi->starting) { /* it's a hello */ struct ceph_x_server_challenge *sc = buf; if (len != sizeof(*sc)) return -EINVAL; xi->server_challenge = le64_to_cpu(sc->server_challenge); dout("handle_reply got server challenge %llx\n", xi->server_challenge); xi->starting = false; xi->have_keys &= ~CEPH_ENTITY_TYPE_AUTH; return -EAGAIN; } op = le16_to_cpu(head->op); result = le32_to_cpu(head->result); dout("handle_reply op %d result %d\n", op, result); switch (op) { case CEPHX_GET_AUTH_SESSION_KEY: /* verify auth key */ ret = ceph_x_proc_ticket_reply(ac, &xi->secret, buf + sizeof(*head), end); break; case CEPHX_GET_PRINCIPAL_SESSION_KEY: th = get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH); if (IS_ERR(th)) return PTR_ERR(th); ret = ceph_x_proc_ticket_reply(ac, &th->session_key, buf + sizeof(*head), end); break; default: return -EINVAL; } if (ret) return ret; if (ac->want_keys == xi->have_keys) return 0; return -EAGAIN; } static void ceph_x_destroy_authorizer(struct ceph_authorizer *a) { struct ceph_x_authorizer *au = (void *)a; ceph_x_authorizer_cleanup(au); kfree(au); } static int ceph_x_create_authorizer( struct ceph_auth_client *ac, int peer_type, struct ceph_auth_handshake *auth) { struct ceph_x_authorizer *au; struct ceph_x_ticket_handler *th; int ret; th = get_ticket_handler(ac, peer_type); if (IS_ERR(th)) return PTR_ERR(th); au = kzalloc(sizeof(*au), GFP_NOFS); if (!au) return -ENOMEM; au->base.destroy = ceph_x_destroy_authorizer; ret = ceph_x_build_authorizer(ac, th, au); if (ret) { kfree(au); return ret; } auth->authorizer = (struct ceph_authorizer *) au; auth->authorizer_buf = au->buf->vec.iov_base; auth->authorizer_buf_len = au->buf->vec.iov_len; auth->authorizer_reply_buf = au->enc_buf; auth->authorizer_reply_buf_len = CEPHX_AU_ENC_BUF_LEN; auth->sign_message = ac->ops->sign_message; auth->check_message_signature = ac->ops->check_message_signature; return 0; } static int ceph_x_update_authorizer( struct ceph_auth_client *ac, int peer_type, struct ceph_auth_handshake *auth) { struct ceph_x_authorizer *au; struct ceph_x_ticket_handler *th; th = get_ticket_handler(ac, peer_type); if (IS_ERR(th)) return PTR_ERR(th); au = (struct ceph_x_authorizer *)auth->authorizer; if (au->secret_id < th->secret_id) { dout("ceph_x_update_authorizer service %u secret %llu < %llu\n", au->service, au->secret_id, th->secret_id); return ceph_x_build_authorizer(ac, th, au); } return 0; } static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac, struct ceph_authorizer *a) { struct ceph_x_authorizer *au = (void *)a; void *p = au->enc_buf; struct ceph_x_authorize_reply *reply = p + ceph_x_encrypt_offset(); int ret; ret = ceph_x_decrypt(&au->session_key, &p, p + CEPHX_AU_ENC_BUF_LEN); if (ret < 0) return ret; if (ret != sizeof(*reply)) return -EPERM; if (au->nonce + 1 != le64_to_cpu(reply->nonce_plus_one)) ret = -EPERM; else ret = 0; dout("verify_authorizer_reply nonce %llx got %llx ret %d\n", au->nonce, le64_to_cpu(reply->nonce_plus_one), ret); return ret; } static void ceph_x_reset(struct ceph_auth_client *ac) { struct ceph_x_info *xi = ac->private; dout("reset\n"); xi->starting = true; xi->server_challenge = 0; } static void ceph_x_destroy(struct ceph_auth_client *ac) { struct ceph_x_info *xi = ac->private; struct rb_node *p; dout("ceph_x_destroy %p\n", ac); ceph_crypto_key_destroy(&xi->secret); while ((p = rb_first(&xi->ticket_handlers)) != NULL) { struct ceph_x_ticket_handler *th = rb_entry(p, struct ceph_x_ticket_handler, node); remove_ticket_handler(ac, th); } ceph_x_authorizer_cleanup(&xi->auth_authorizer); kfree(ac->private); ac->private = NULL; } static void invalidate_ticket(struct ceph_auth_client *ac, int peer_type) { struct ceph_x_ticket_handler *th; th = get_ticket_handler(ac, peer_type); if (!IS_ERR(th)) th->have_key = false; } static void ceph_x_invalidate_authorizer(struct ceph_auth_client *ac, int peer_type) { /* * We are to invalidate a service ticket in the hopes of * getting a new, hopefully more valid, one. But, we won't get * it unless our AUTH ticket is good, so invalidate AUTH ticket * as well, just in case. */ invalidate_ticket(ac, peer_type); invalidate_ticket(ac, CEPH_ENTITY_TYPE_AUTH); } static int calc_signature(struct ceph_x_authorizer *au, struct ceph_msg *msg, __le64 *psig) { void *enc_buf = au->enc_buf; struct { __le32 len; __le32 header_crc; __le32 front_crc; __le32 middle_crc; __le32 data_crc; } __packed *sigblock = enc_buf + ceph_x_encrypt_offset(); int ret; sigblock->len = cpu_to_le32(4*sizeof(u32)); sigblock->header_crc = msg->hdr.crc; sigblock->front_crc = msg->footer.front_crc; sigblock->middle_crc = msg->footer.middle_crc; sigblock->data_crc = msg->footer.data_crc; ret = ceph_x_encrypt(&au->session_key, enc_buf, CEPHX_AU_ENC_BUF_LEN, sizeof(*sigblock)); if (ret < 0) return ret; *psig = *(__le64 *)(enc_buf + sizeof(u32)); return 0; } static int ceph_x_sign_message(struct ceph_auth_handshake *auth, struct ceph_msg *msg) { __le64 sig; int ret; if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN)) return 0; ret = calc_signature((struct ceph_x_authorizer *)auth->authorizer, msg, &sig); if (ret) return ret; msg->footer.sig = sig; msg->footer.flags |= CEPH_MSG_FOOTER_SIGNED; return 0; } static int ceph_x_check_message_signature(struct ceph_auth_handshake *auth, struct ceph_msg *msg) { __le64 sig_check; int ret; if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN)) return 0; ret = calc_signature((struct ceph_x_authorizer *)auth->authorizer, msg, &sig_check); if (ret) return ret; if (sig_check == msg->footer.sig) return 0; if (msg->footer.flags & CEPH_MSG_FOOTER_SIGNED) dout("ceph_x_check_message_signature %p has signature %llx " "expect %llx\n", msg, msg->footer.sig, sig_check); else dout("ceph_x_check_message_signature %p sender did not set " "CEPH_MSG_FOOTER_SIGNED\n", msg); return -EBADMSG; } static const struct ceph_auth_client_ops ceph_x_ops = { .name = "x", .is_authenticated = ceph_x_is_authenticated, .should_authenticate = ceph_x_should_authenticate, .build_request = ceph_x_build_request, .handle_reply = ceph_x_handle_reply, .create_authorizer = ceph_x_create_authorizer, .update_authorizer = ceph_x_update_authorizer, .verify_authorizer_reply = ceph_x_verify_authorizer_reply, .invalidate_authorizer = ceph_x_invalidate_authorizer, .reset = ceph_x_reset, .destroy = ceph_x_destroy, .sign_message = ceph_x_sign_message, .check_message_signature = ceph_x_check_message_signature, }; int ceph_x_init(struct ceph_auth_client *ac) { struct ceph_x_info *xi; int ret; dout("ceph_x_init %p\n", ac); ret = -ENOMEM; xi = kzalloc(sizeof(*xi), GFP_NOFS); if (!xi) goto out; ret = -EINVAL; if (!ac->key) { pr_err("no secret set (for auth_x protocol)\n"); goto out_nomem; } ret = ceph_crypto_key_clone(&xi->secret, ac->key); if (ret < 0) { pr_err("cannot clone key: %d\n", ret); goto out_nomem; } xi->starting = true; xi->ticket_handlers = RB_ROOT; ac->protocol = CEPH_AUTH_CEPHX; ac->private = xi; ac->ops = &ceph_x_ops; return 0; out_nomem: kfree(xi); out: return ret; }