diff options
Diffstat (limited to 'fs/ceph/auth_x.c')
| -rw-r--r-- | fs/ceph/auth_x.c | 680 |
1 files changed, 680 insertions, 0 deletions
diff --git a/fs/ceph/auth_x.c b/fs/ceph/auth_x.c new file mode 100644 index 000000000000..d9001a4dc8cc --- /dev/null +++ b/fs/ceph/auth_x.c @@ -0,0 +1,680 @@ + +#include "ceph_debug.h" + +#include <linux/err.h> +#include <linux/module.h> +#include <linux/random.h> +#include <linux/slab.h> + +#include "auth_x.h" +#include "auth_x_protocol.h" +#include "crypto.h" +#include "auth.h" +#include "decode.h" + +struct kmem_cache *ceph_x_ticketbuf_cachep; + +#define TEMP_TICKET_BUF_LEN 256 + +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_encrypt_buflen(int ilen) +{ + return sizeof(struct ceph_x_encrypt_header) + ilen + 16 + + sizeof(u32); +} + +static int ceph_x_encrypt(struct ceph_crypto_key *secret, + void *ibuf, int ilen, void *obuf, size_t olen) +{ + struct ceph_x_encrypt_header head = { + .struct_v = 1, + .magic = cpu_to_le64(CEPHX_ENC_MAGIC) + }; + size_t len = olen - sizeof(u32); + int ret; + + ret = ceph_encrypt2(secret, obuf + sizeof(u32), &len, + &head, sizeof(head), ibuf, ilen); + if (ret) + return ret; + ceph_encode_32(&obuf, len); + return len + sizeof(u32); +} + +static int ceph_x_decrypt(struct ceph_crypto_key *secret, + void **p, void *end, void *obuf, size_t olen) +{ + struct ceph_x_encrypt_header head; + size_t head_len = sizeof(head); + int len, ret; + + len = ceph_decode_32(p); + if (*p + len > end) + return -EINVAL; + + dout("ceph_x_decrypt len %d\n", len); + ret = ceph_decrypt2(secret, &head, &head_len, obuf, &olen, + *p, len); + if (ret) + return ret; + if (head.struct_v != 1 || le64_to_cpu(head.magic) != CEPHX_ENC_MAGIC) + return -EPERM; + *p += len; + return olen; +} + +/* + * get existing (or insert new) ticket handler + */ +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 ceph_x_proc_ticket_reply(struct ceph_auth_client *ac, + struct ceph_crypto_key *secret, + void *buf, void *end) +{ + struct ceph_x_info *xi = ac->private; + int num; + void *p = buf; + int ret; + char *dbuf; + char *ticket_buf; + u8 struct_v; + + dbuf = kmem_cache_alloc(ceph_x_ticketbuf_cachep, GFP_NOFS | GFP_ATOMIC); + if (!dbuf) + return -ENOMEM; + + ret = -ENOMEM; + ticket_buf = kmem_cache_alloc(ceph_x_ticketbuf_cachep, + GFP_NOFS | GFP_ATOMIC); + if (!ticket_buf) + goto out_dbuf; + + ceph_decode_need(&p, end, 1 + sizeof(u32), bad); + struct_v = ceph_decode_8(&p); + if (struct_v != 1) + goto bad; + num = ceph_decode_32(&p); + dout("%d tickets\n", num); + while (num--) { + int type; + u8 struct_v; + struct ceph_x_ticket_handler *th; + void *dp, *dend; + int dlen; + char is_enc; + struct timespec validity; + struct ceph_crypto_key old_key; + void *tp, *tpend; + struct ceph_timespec new_validity; + struct ceph_crypto_key new_session_key; + struct ceph_buffer *new_ticket_blob; + unsigned long new_expires, new_renew_after; + u64 new_secret_id; + + 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)); + + struct_v = ceph_decode_8(&p); + if (struct_v != 1) + goto bad; + + th = get_ticket_handler(ac, type); + if (IS_ERR(th)) { + ret = PTR_ERR(th); + goto out; + } + + /* blob for me */ + dlen = ceph_x_decrypt(secret, &p, end, dbuf, + TEMP_TICKET_BUF_LEN); + if (dlen <= 0) { + ret = dlen; + goto out; + } + dout(" decrypted %d bytes\n", dlen); + dend = dbuf + dlen; + dp = dbuf; + + struct_v = ceph_decode_8(&dp); + if (struct_v != 1) + goto bad; + + memcpy(&old_key, &th->session_key, sizeof(old_key)); + ret = ceph_crypto_key_decode(&new_session_key, &dp, dend); + if (ret) + goto out; + + ceph_decode_copy(&dp, &new_validity, sizeof(new_validity)); + ceph_decode_timespec(&validity, &new_validity); + new_expires = get_seconds() + validity.tv_sec; + new_renew_after = new_expires - (validity.tv_sec / 4); + dout(" expires=%lu renew_after=%lu\n", new_expires, + new_renew_after); + + /* ticket blob for service */ + ceph_decode_8_safe(&p, end, is_enc, bad); + tp = ticket_buf; + if (is_enc) { + /* encrypted */ + dout(" encrypted ticket\n"); + dlen = ceph_x_decrypt(&old_key, &p, end, ticket_buf, + TEMP_TICKET_BUF_LEN); + if (dlen < 0) { + ret = dlen; + goto out; + } + dlen = ceph_decode_32(&tp); + } else { + /* unencrypted */ + ceph_decode_32_safe(&p, end, dlen, bad); + ceph_decode_need(&p, end, dlen, bad); + ceph_decode_copy(&p, ticket_buf, dlen); + } + tpend = tp + dlen; + dout(" ticket blob is %d bytes\n", dlen); + ceph_decode_need(&tp, tpend, 1 + sizeof(u64), bad); + struct_v = ceph_decode_8(&tp); + new_secret_id = ceph_decode_64(&tp); + ret = ceph_decode_buffer(&new_ticket_blob, &tp, 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->validity = new_validity; + th->secret_id = new_secret_id; + th->expires = new_expires; + th->renew_after = new_renew_after; + 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; + } + + ret = 0; +out: + kmem_cache_free(ceph_x_ticketbuf_cachep, ticket_buf); +out_dbuf: + kmem_cache_free(ceph_x_ticketbuf_cachep, dbuf); + return ret; + +bad: + ret = -EINVAL; + goto out; +} + +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); + + maxlen = sizeof(*msg_a) + sizeof(msg_b) + + ceph_x_encrypt_buflen(ticket_blob_len); + 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) + return -ENOMEM; + } + au->service = th->service; + + 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; + + get_random_bytes(&au->nonce, sizeof(au->nonce)); + msg_b.struct_v = 1; + msg_b.nonce = cpu_to_le64(au->nonce); + ret = ceph_x_encrypt(&th->session_key, &msg_b, sizeof(msg_b), + p, end - p); + if (ret < 0) + goto out_buf; + p += ret; + 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); + BUG_ON(au->buf->vec.iov_len > maxlen); + return 0; + +out_buf: + ceph_buffer_put(au->buf); + au->buf = NULL; + 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 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 (!th) { + *pneed |= service; + continue; + } + + if (get_seconds() >= th->renew_after) + *pneed |= service; + if (get_seconds() >= th->expires) + 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); + + 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; + struct ceph_x_challenge_blob tmp; + char tmp_enc[40]; + 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)); + tmp.client_challenge = auth->client_challenge; + tmp.server_challenge = cpu_to_le64(xi->server_challenge); + ret = ceph_x_encrypt(&xi->secret, &tmp, sizeof(tmp), + tmp_enc, sizeof(tmp_enc)); + if (ret < 0) + return ret; + + auth->struct_v = 1; + auth->key = 0; + for (u = (u64 *)tmp_enc; u + 1 <= (u64 *)(tmp_enc + ret); u++) + auth->key ^= *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); + + BUG_ON(!th); + 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 = le32_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); + BUG_ON(!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 int ceph_x_create_authorizer( + struct ceph_auth_client *ac, int peer_type, + struct ceph_authorizer **a, + void **buf, size_t *len, + void **reply_buf, size_t *reply_len) +{ + 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; + + ret = ceph_x_build_authorizer(ac, th, au); + if (ret) { + kfree(au); + return ret; + } + + *a = (struct ceph_authorizer *)au; + *buf = au->buf->vec.iov_base; + *len = au->buf->vec.iov_len; + *reply_buf = au->reply_buf; + *reply_len = sizeof(au->reply_buf); + return 0; +} + +static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac, + struct ceph_authorizer *a, size_t len) +{ + struct ceph_x_authorizer *au = (void *)a; + struct ceph_x_ticket_handler *th; + int ret = 0; + struct ceph_x_authorize_reply reply; + void *p = au->reply_buf; + void *end = p + sizeof(au->reply_buf); + + th = get_ticket_handler(ac, au->service); + if (!th) + return -EIO; /* hrm! */ + ret = ceph_x_decrypt(&th->session_key, &p, end, &reply, sizeof(reply)); + 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_destroy_authorizer(struct ceph_auth_client *ac, + struct ceph_authorizer *a) +{ + struct ceph_x_authorizer *au = (void *)a; + + ceph_buffer_put(au->buf); + kfree(au); +} + + +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); + } + + kmem_cache_destroy(ceph_x_ticketbuf_cachep); + + kfree(ac->private); + ac->private = NULL; +} + +static void ceph_x_invalidate_authorizer(struct ceph_auth_client *ac, + int peer_type) +{ + struct ceph_x_ticket_handler *th; + + th = get_ticket_handler(ac, peer_type); + if (th && !IS_ERR(th)) + remove_ticket_handler(ac, th); +} + + +static const struct ceph_auth_client_ops ceph_x_ops = { + .is_authenticated = ceph_x_is_authenticated, + .build_request = ceph_x_build_request, + .handle_reply = ceph_x_handle_reply, + .create_authorizer = ceph_x_create_authorizer, + .verify_authorizer_reply = ceph_x_verify_authorizer_reply, + .destroy_authorizer = ceph_x_destroy_authorizer, + .invalidate_authorizer = ceph_x_invalidate_authorizer, + .reset = ceph_x_reset, + .destroy = ceph_x_destroy, +}; + + +int ceph_x_init(struct ceph_auth_client *ac) +{ + struct ceph_x_info *xi; + int ret; + + dout("ceph_x_init %p\n", ac); + xi = kzalloc(sizeof(*xi), GFP_NOFS); + if (!xi) + return -ENOMEM; + + ret = -ENOMEM; + ceph_x_ticketbuf_cachep = kmem_cache_create("ceph_x_ticketbuf", + TEMP_TICKET_BUF_LEN, 8, + (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD), + NULL); + if (!ceph_x_ticketbuf_cachep) + goto done_nomem; + ret = -EINVAL; + if (!ac->secret) { + pr_err("no secret set (for auth_x protocol)\n"); + goto done_nomem; + } + + ret = ceph_crypto_key_unarmor(&xi->secret, ac->secret); + if (ret) + goto done_nomem; + + xi->starting = true; + xi->ticket_handlers = RB_ROOT; + + ac->protocol = CEPH_AUTH_CEPHX; + ac->private = xi; + ac->ops = &ceph_x_ops; + return 0; + +done_nomem: + kfree(xi); + if (ceph_x_ticketbuf_cachep) + kmem_cache_destroy(ceph_x_ticketbuf_cachep); + return ret; +} + + |