linux/net/ceph/auth_x.c
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   1// SPDX-License-Identifier: GPL-2.0
   2
   3#include <linux/ceph/ceph_debug.h>
   4
   5#include <linux/err.h>
   6#include <linux/module.h>
   7#include <linux/random.h>
   8#include <linux/slab.h>
   9
  10#include <linux/ceph/decode.h>
  11#include <linux/ceph/auth.h>
  12#include <linux/ceph/ceph_features.h>
  13#include <linux/ceph/libceph.h>
  14#include <linux/ceph/messenger.h>
  15
  16#include "crypto.h"
  17#include "auth_x.h"
  18#include "auth_x_protocol.h"
  19
  20static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed);
  21
  22static int ceph_x_is_authenticated(struct ceph_auth_client *ac)
  23{
  24        struct ceph_x_info *xi = ac->private;
  25        int need;
  26
  27        ceph_x_validate_tickets(ac, &need);
  28        dout("ceph_x_is_authenticated want=%d need=%d have=%d\n",
  29             ac->want_keys, need, xi->have_keys);
  30        return (ac->want_keys & xi->have_keys) == ac->want_keys;
  31}
  32
  33static int ceph_x_should_authenticate(struct ceph_auth_client *ac)
  34{
  35        struct ceph_x_info *xi = ac->private;
  36        int need;
  37
  38        ceph_x_validate_tickets(ac, &need);
  39        dout("ceph_x_should_authenticate want=%d need=%d have=%d\n",
  40             ac->want_keys, need, xi->have_keys);
  41        return need != 0;
  42}
  43
  44static int ceph_x_encrypt_offset(void)
  45{
  46        return sizeof(u32) + sizeof(struct ceph_x_encrypt_header);
  47}
  48
  49static int ceph_x_encrypt_buflen(int ilen)
  50{
  51        return ceph_x_encrypt_offset() + ilen + 16;
  52}
  53
  54static int ceph_x_encrypt(struct ceph_crypto_key *secret, void *buf,
  55                          int buf_len, int plaintext_len)
  56{
  57        struct ceph_x_encrypt_header *hdr = buf + sizeof(u32);
  58        int ciphertext_len;
  59        int ret;
  60
  61        hdr->struct_v = 1;
  62        hdr->magic = cpu_to_le64(CEPHX_ENC_MAGIC);
  63
  64        ret = ceph_crypt(secret, true, buf + sizeof(u32), buf_len - sizeof(u32),
  65                         plaintext_len + sizeof(struct ceph_x_encrypt_header),
  66                         &ciphertext_len);
  67        if (ret)
  68                return ret;
  69
  70        ceph_encode_32(&buf, ciphertext_len);
  71        return sizeof(u32) + ciphertext_len;
  72}
  73
  74static int __ceph_x_decrypt(struct ceph_crypto_key *secret, void *p,
  75                            int ciphertext_len)
  76{
  77        struct ceph_x_encrypt_header *hdr = p;
  78        int plaintext_len;
  79        int ret;
  80
  81        ret = ceph_crypt(secret, false, p, ciphertext_len, ciphertext_len,
  82                         &plaintext_len);
  83        if (ret)
  84                return ret;
  85
  86        if (le64_to_cpu(hdr->magic) != CEPHX_ENC_MAGIC) {
  87                pr_err("%s bad magic\n", __func__);
  88                return -EINVAL;
  89        }
  90
  91        return plaintext_len - sizeof(*hdr);
  92}
  93
  94static int ceph_x_decrypt(struct ceph_crypto_key *secret, void **p, void *end)
  95{
  96        int ciphertext_len;
  97        int ret;
  98
  99        ceph_decode_32_safe(p, end, ciphertext_len, e_inval);
 100        ceph_decode_need(p, end, ciphertext_len, e_inval);
 101
 102        ret = __ceph_x_decrypt(secret, *p, ciphertext_len);
 103        if (ret < 0)
 104                return ret;
 105
 106        *p += ciphertext_len;
 107        return ret;
 108
 109e_inval:
 110        return -EINVAL;
 111}
 112
 113/*
 114 * get existing (or insert new) ticket handler
 115 */
 116static struct ceph_x_ticket_handler *
 117get_ticket_handler(struct ceph_auth_client *ac, int service)
 118{
 119        struct ceph_x_ticket_handler *th;
 120        struct ceph_x_info *xi = ac->private;
 121        struct rb_node *parent = NULL, **p = &xi->ticket_handlers.rb_node;
 122
 123        while (*p) {
 124                parent = *p;
 125                th = rb_entry(parent, struct ceph_x_ticket_handler, node);
 126                if (service < th->service)
 127                        p = &(*p)->rb_left;
 128                else if (service > th->service)
 129                        p = &(*p)->rb_right;
 130                else
 131                        return th;
 132        }
 133
 134        /* add it */
 135        th = kzalloc(sizeof(*th), GFP_NOFS);
 136        if (!th)
 137                return ERR_PTR(-ENOMEM);
 138        th->service = service;
 139        rb_link_node(&th->node, parent, p);
 140        rb_insert_color(&th->node, &xi->ticket_handlers);
 141        return th;
 142}
 143
 144static void remove_ticket_handler(struct ceph_auth_client *ac,
 145                                  struct ceph_x_ticket_handler *th)
 146{
 147        struct ceph_x_info *xi = ac->private;
 148
 149        dout("remove_ticket_handler %p %d\n", th, th->service);
 150        rb_erase(&th->node, &xi->ticket_handlers);
 151        ceph_crypto_key_destroy(&th->session_key);
 152        if (th->ticket_blob)
 153                ceph_buffer_put(th->ticket_blob);
 154        kfree(th);
 155}
 156
 157static int process_one_ticket(struct ceph_auth_client *ac,
 158                              struct ceph_crypto_key *secret,
 159                              void **p, void *end)
 160{
 161        struct ceph_x_info *xi = ac->private;
 162        int type;
 163        u8 tkt_struct_v, blob_struct_v;
 164        struct ceph_x_ticket_handler *th;
 165        void *dp, *dend;
 166        int dlen;
 167        char is_enc;
 168        struct timespec64 validity;
 169        void *tp, *tpend;
 170        void **ptp;
 171        struct ceph_crypto_key new_session_key = { 0 };
 172        struct ceph_buffer *new_ticket_blob;
 173        time64_t new_expires, new_renew_after;
 174        u64 new_secret_id;
 175        int ret;
 176
 177        ceph_decode_need(p, end, sizeof(u32) + 1, bad);
 178
 179        type = ceph_decode_32(p);
 180        dout(" ticket type %d %s\n", type, ceph_entity_type_name(type));
 181
 182        tkt_struct_v = ceph_decode_8(p);
 183        if (tkt_struct_v != 1)
 184                goto bad;
 185
 186        th = get_ticket_handler(ac, type);
 187        if (IS_ERR(th)) {
 188                ret = PTR_ERR(th);
 189                goto out;
 190        }
 191
 192        /* blob for me */
 193        dp = *p + ceph_x_encrypt_offset();
 194        ret = ceph_x_decrypt(secret, p, end);
 195        if (ret < 0)
 196                goto out;
 197        dout(" decrypted %d bytes\n", ret);
 198        dend = dp + ret;
 199
 200        tkt_struct_v = ceph_decode_8(&dp);
 201        if (tkt_struct_v != 1)
 202                goto bad;
 203
 204        ret = ceph_crypto_key_decode(&new_session_key, &dp, dend);
 205        if (ret)
 206                goto out;
 207
 208        ceph_decode_timespec64(&validity, dp);
 209        dp += sizeof(struct ceph_timespec);
 210        new_expires = ktime_get_real_seconds() + validity.tv_sec;
 211        new_renew_after = new_expires - (validity.tv_sec / 4);
 212        dout(" expires=%llu renew_after=%llu\n", new_expires,
 213             new_renew_after);
 214
 215        /* ticket blob for service */
 216        ceph_decode_8_safe(p, end, is_enc, bad);
 217        if (is_enc) {
 218                /* encrypted */
 219                tp = *p + ceph_x_encrypt_offset();
 220                ret = ceph_x_decrypt(&th->session_key, p, end);
 221                if (ret < 0)
 222                        goto out;
 223                dout(" encrypted ticket, decrypted %d bytes\n", ret);
 224                ptp = &tp;
 225                tpend = tp + ret;
 226        } else {
 227                /* unencrypted */
 228                ptp = p;
 229                tpend = end;
 230        }
 231        ceph_decode_32_safe(ptp, tpend, dlen, bad);
 232        dout(" ticket blob is %d bytes\n", dlen);
 233        ceph_decode_need(ptp, tpend, 1 + sizeof(u64), bad);
 234        blob_struct_v = ceph_decode_8(ptp);
 235        if (blob_struct_v != 1)
 236                goto bad;
 237
 238        new_secret_id = ceph_decode_64(ptp);
 239        ret = ceph_decode_buffer(&new_ticket_blob, ptp, tpend);
 240        if (ret)
 241                goto out;
 242
 243        /* all is well, update our ticket */
 244        ceph_crypto_key_destroy(&th->session_key);
 245        if (th->ticket_blob)
 246                ceph_buffer_put(th->ticket_blob);
 247        th->session_key = new_session_key;
 248        th->ticket_blob = new_ticket_blob;
 249        th->secret_id = new_secret_id;
 250        th->expires = new_expires;
 251        th->renew_after = new_renew_after;
 252        th->have_key = true;
 253        dout(" got ticket service %d (%s) secret_id %lld len %d\n",
 254             type, ceph_entity_type_name(type), th->secret_id,
 255             (int)th->ticket_blob->vec.iov_len);
 256        xi->have_keys |= th->service;
 257        return 0;
 258
 259bad:
 260        ret = -EINVAL;
 261out:
 262        ceph_crypto_key_destroy(&new_session_key);
 263        return ret;
 264}
 265
 266static int ceph_x_proc_ticket_reply(struct ceph_auth_client *ac,
 267                                    struct ceph_crypto_key *secret,
 268                                    void *buf, void *end)
 269{
 270        void *p = buf;
 271        u8 reply_struct_v;
 272        u32 num;
 273        int ret;
 274
 275        ceph_decode_8_safe(&p, end, reply_struct_v, bad);
 276        if (reply_struct_v != 1)
 277                return -EINVAL;
 278
 279        ceph_decode_32_safe(&p, end, num, bad);
 280        dout("%d tickets\n", num);
 281
 282        while (num--) {
 283                ret = process_one_ticket(ac, secret, &p, end);
 284                if (ret)
 285                        return ret;
 286        }
 287
 288        return 0;
 289
 290bad:
 291        return -EINVAL;
 292}
 293
 294/*
 295 * Encode and encrypt the second part (ceph_x_authorize_b) of the
 296 * authorizer.  The first part (ceph_x_authorize_a) should already be
 297 * encoded.
 298 */
 299static int encrypt_authorizer(struct ceph_x_authorizer *au,
 300                              u64 *server_challenge)
 301{
 302        struct ceph_x_authorize_a *msg_a;
 303        struct ceph_x_authorize_b *msg_b;
 304        void *p, *end;
 305        int ret;
 306
 307        msg_a = au->buf->vec.iov_base;
 308        WARN_ON(msg_a->ticket_blob.secret_id != cpu_to_le64(au->secret_id));
 309        p = (void *)(msg_a + 1) + le32_to_cpu(msg_a->ticket_blob.blob_len);
 310        end = au->buf->vec.iov_base + au->buf->vec.iov_len;
 311
 312        msg_b = p + ceph_x_encrypt_offset();
 313        msg_b->struct_v = 2;
 314        msg_b->nonce = cpu_to_le64(au->nonce);
 315        if (server_challenge) {
 316                msg_b->have_challenge = 1;
 317                msg_b->server_challenge_plus_one =
 318                    cpu_to_le64(*server_challenge + 1);
 319        } else {
 320                msg_b->have_challenge = 0;
 321                msg_b->server_challenge_plus_one = 0;
 322        }
 323
 324        ret = ceph_x_encrypt(&au->session_key, p, end - p, sizeof(*msg_b));
 325        if (ret < 0)
 326                return ret;
 327
 328        p += ret;
 329        if (server_challenge) {
 330                WARN_ON(p != end);
 331        } else {
 332                WARN_ON(p > end);
 333                au->buf->vec.iov_len = p - au->buf->vec.iov_base;
 334        }
 335
 336        return 0;
 337}
 338
 339static void ceph_x_authorizer_cleanup(struct ceph_x_authorizer *au)
 340{
 341        ceph_crypto_key_destroy(&au->session_key);
 342        if (au->buf) {
 343                ceph_buffer_put(au->buf);
 344                au->buf = NULL;
 345        }
 346}
 347
 348static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
 349                                   struct ceph_x_ticket_handler *th,
 350                                   struct ceph_x_authorizer *au)
 351{
 352        int maxlen;
 353        struct ceph_x_authorize_a *msg_a;
 354        struct ceph_x_authorize_b *msg_b;
 355        int ret;
 356        int ticket_blob_len =
 357                (th->ticket_blob ? th->ticket_blob->vec.iov_len : 0);
 358
 359        dout("build_authorizer for %s %p\n",
 360             ceph_entity_type_name(th->service), au);
 361
 362        ceph_crypto_key_destroy(&au->session_key);
 363        ret = ceph_crypto_key_clone(&au->session_key, &th->session_key);
 364        if (ret)
 365                goto out_au;
 366
 367        maxlen = sizeof(*msg_a) + ticket_blob_len +
 368                ceph_x_encrypt_buflen(sizeof(*msg_b));
 369        dout("  need len %d\n", maxlen);
 370        if (au->buf && au->buf->alloc_len < maxlen) {
 371                ceph_buffer_put(au->buf);
 372                au->buf = NULL;
 373        }
 374        if (!au->buf) {
 375                au->buf = ceph_buffer_new(maxlen, GFP_NOFS);
 376                if (!au->buf) {
 377                        ret = -ENOMEM;
 378                        goto out_au;
 379                }
 380        }
 381        au->service = th->service;
 382        au->secret_id = th->secret_id;
 383
 384        msg_a = au->buf->vec.iov_base;
 385        msg_a->struct_v = 1;
 386        msg_a->global_id = cpu_to_le64(ac->global_id);
 387        msg_a->service_id = cpu_to_le32(th->service);
 388        msg_a->ticket_blob.struct_v = 1;
 389        msg_a->ticket_blob.secret_id = cpu_to_le64(th->secret_id);
 390        msg_a->ticket_blob.blob_len = cpu_to_le32(ticket_blob_len);
 391        if (ticket_blob_len) {
 392                memcpy(msg_a->ticket_blob.blob, th->ticket_blob->vec.iov_base,
 393                       th->ticket_blob->vec.iov_len);
 394        }
 395        dout(" th %p secret_id %lld %lld\n", th, th->secret_id,
 396             le64_to_cpu(msg_a->ticket_blob.secret_id));
 397
 398        get_random_bytes(&au->nonce, sizeof(au->nonce));
 399        ret = encrypt_authorizer(au, NULL);
 400        if (ret) {
 401                pr_err("failed to encrypt authorizer: %d", ret);
 402                goto out_au;
 403        }
 404
 405        dout(" built authorizer nonce %llx len %d\n", au->nonce,
 406             (int)au->buf->vec.iov_len);
 407        return 0;
 408
 409out_au:
 410        ceph_x_authorizer_cleanup(au);
 411        return ret;
 412}
 413
 414static int ceph_x_encode_ticket(struct ceph_x_ticket_handler *th,
 415                                void **p, void *end)
 416{
 417        ceph_decode_need(p, end, 1 + sizeof(u64), bad);
 418        ceph_encode_8(p, 1);
 419        ceph_encode_64(p, th->secret_id);
 420        if (th->ticket_blob) {
 421                const char *buf = th->ticket_blob->vec.iov_base;
 422                u32 len = th->ticket_blob->vec.iov_len;
 423
 424                ceph_encode_32_safe(p, end, len, bad);
 425                ceph_encode_copy_safe(p, end, buf, len, bad);
 426        } else {
 427                ceph_encode_32_safe(p, end, 0, bad);
 428        }
 429
 430        return 0;
 431bad:
 432        return -ERANGE;
 433}
 434
 435static bool need_key(struct ceph_x_ticket_handler *th)
 436{
 437        if (!th->have_key)
 438                return true;
 439
 440        return ktime_get_real_seconds() >= th->renew_after;
 441}
 442
 443static bool have_key(struct ceph_x_ticket_handler *th)
 444{
 445        if (th->have_key) {
 446                if (ktime_get_real_seconds() >= th->expires)
 447                        th->have_key = false;
 448        }
 449
 450        return th->have_key;
 451}
 452
 453static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed)
 454{
 455        int want = ac->want_keys;
 456        struct ceph_x_info *xi = ac->private;
 457        int service;
 458
 459        *pneed = ac->want_keys & ~(xi->have_keys);
 460
 461        for (service = 1; service <= want; service <<= 1) {
 462                struct ceph_x_ticket_handler *th;
 463
 464                if (!(ac->want_keys & service))
 465                        continue;
 466
 467                if (*pneed & service)
 468                        continue;
 469
 470                th = get_ticket_handler(ac, service);
 471                if (IS_ERR(th)) {
 472                        *pneed |= service;
 473                        continue;
 474                }
 475
 476                if (need_key(th))
 477                        *pneed |= service;
 478                if (!have_key(th))
 479                        xi->have_keys &= ~service;
 480        }
 481}
 482
 483static int ceph_x_build_request(struct ceph_auth_client *ac,
 484                                void *buf, void *end)
 485{
 486        struct ceph_x_info *xi = ac->private;
 487        int need;
 488        struct ceph_x_request_header *head = buf;
 489        int ret;
 490        struct ceph_x_ticket_handler *th =
 491                get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
 492
 493        if (IS_ERR(th))
 494                return PTR_ERR(th);
 495
 496        ceph_x_validate_tickets(ac, &need);
 497
 498        dout("build_request want %x have %x need %x\n",
 499             ac->want_keys, xi->have_keys, need);
 500
 501        if (need & CEPH_ENTITY_TYPE_AUTH) {
 502                struct ceph_x_authenticate *auth = (void *)(head + 1);
 503                void *p = auth + 1;
 504                void *enc_buf = xi->auth_authorizer.enc_buf;
 505                struct ceph_x_challenge_blob *blob = enc_buf +
 506                                                        ceph_x_encrypt_offset();
 507                u64 *u;
 508
 509                if (p > end)
 510                        return -ERANGE;
 511
 512                dout(" get_auth_session_key\n");
 513                head->op = cpu_to_le16(CEPHX_GET_AUTH_SESSION_KEY);
 514
 515                /* encrypt and hash */
 516                get_random_bytes(&auth->client_challenge, sizeof(u64));
 517                blob->client_challenge = auth->client_challenge;
 518                blob->server_challenge = cpu_to_le64(xi->server_challenge);
 519                ret = ceph_x_encrypt(&xi->secret, enc_buf, CEPHX_AU_ENC_BUF_LEN,
 520                                     sizeof(*blob));
 521                if (ret < 0)
 522                        return ret;
 523
 524                auth->struct_v = 1;
 525                auth->key = 0;
 526                for (u = (u64 *)enc_buf; u + 1 <= (u64 *)(enc_buf + ret); u++)
 527                        auth->key ^= *(__le64 *)u;
 528                dout(" server_challenge %llx client_challenge %llx key %llx\n",
 529                     xi->server_challenge, le64_to_cpu(auth->client_challenge),
 530                     le64_to_cpu(auth->key));
 531
 532                /* now encode the old ticket if exists */
 533                ret = ceph_x_encode_ticket(th, &p, end);
 534                if (ret < 0)
 535                        return ret;
 536
 537                return p - buf;
 538        }
 539
 540        if (need) {
 541                void *p = head + 1;
 542                struct ceph_x_service_ticket_request *req;
 543
 544                if (p > end)
 545                        return -ERANGE;
 546                head->op = cpu_to_le16(CEPHX_GET_PRINCIPAL_SESSION_KEY);
 547
 548                ret = ceph_x_build_authorizer(ac, th, &xi->auth_authorizer);
 549                if (ret)
 550                        return ret;
 551                ceph_encode_copy(&p, xi->auth_authorizer.buf->vec.iov_base,
 552                                 xi->auth_authorizer.buf->vec.iov_len);
 553
 554                req = p;
 555                req->keys = cpu_to_le32(need);
 556                p += sizeof(*req);
 557                return p - buf;
 558        }
 559
 560        return 0;
 561}
 562
 563static int ceph_x_handle_reply(struct ceph_auth_client *ac, int result,
 564                               void *buf, void *end)
 565{
 566        struct ceph_x_info *xi = ac->private;
 567        struct ceph_x_reply_header *head = buf;
 568        struct ceph_x_ticket_handler *th;
 569        int len = end - buf;
 570        int op;
 571        int ret;
 572
 573        if (result)
 574                return result;  /* XXX hmm? */
 575
 576        if (xi->starting) {
 577                /* it's a hello */
 578                struct ceph_x_server_challenge *sc = buf;
 579
 580                if (len != sizeof(*sc))
 581                        return -EINVAL;
 582                xi->server_challenge = le64_to_cpu(sc->server_challenge);
 583                dout("handle_reply got server challenge %llx\n",
 584                     xi->server_challenge);
 585                xi->starting = false;
 586                xi->have_keys &= ~CEPH_ENTITY_TYPE_AUTH;
 587                return -EAGAIN;
 588        }
 589
 590        op = le16_to_cpu(head->op);
 591        result = le32_to_cpu(head->result);
 592        dout("handle_reply op %d result %d\n", op, result);
 593        switch (op) {
 594        case CEPHX_GET_AUTH_SESSION_KEY:
 595                /* verify auth key */
 596                ret = ceph_x_proc_ticket_reply(ac, &xi->secret,
 597                                               buf + sizeof(*head), end);
 598                break;
 599
 600        case CEPHX_GET_PRINCIPAL_SESSION_KEY:
 601                th = get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH);
 602                if (IS_ERR(th))
 603                        return PTR_ERR(th);
 604                ret = ceph_x_proc_ticket_reply(ac, &th->session_key,
 605                                               buf + sizeof(*head), end);
 606                break;
 607
 608        default:
 609                return -EINVAL;
 610        }
 611        if (ret)
 612                return ret;
 613        if (ac->want_keys == xi->have_keys)
 614                return 0;
 615        return -EAGAIN;
 616}
 617
 618static void ceph_x_destroy_authorizer(struct ceph_authorizer *a)
 619{
 620        struct ceph_x_authorizer *au = (void *)a;
 621
 622        ceph_x_authorizer_cleanup(au);
 623        kfree(au);
 624}
 625
 626static int ceph_x_create_authorizer(
 627        struct ceph_auth_client *ac, int peer_type,
 628        struct ceph_auth_handshake *auth)
 629{
 630        struct ceph_x_authorizer *au;
 631        struct ceph_x_ticket_handler *th;
 632        int ret;
 633
 634        th = get_ticket_handler(ac, peer_type);
 635        if (IS_ERR(th))
 636                return PTR_ERR(th);
 637
 638        au = kzalloc(sizeof(*au), GFP_NOFS);
 639        if (!au)
 640                return -ENOMEM;
 641
 642        au->base.destroy = ceph_x_destroy_authorizer;
 643
 644        ret = ceph_x_build_authorizer(ac, th, au);
 645        if (ret) {
 646                kfree(au);
 647                return ret;
 648        }
 649
 650        auth->authorizer = (struct ceph_authorizer *) au;
 651        auth->authorizer_buf = au->buf->vec.iov_base;
 652        auth->authorizer_buf_len = au->buf->vec.iov_len;
 653        auth->authorizer_reply_buf = au->enc_buf;
 654        auth->authorizer_reply_buf_len = CEPHX_AU_ENC_BUF_LEN;
 655        auth->sign_message = ac->ops->sign_message;
 656        auth->check_message_signature = ac->ops->check_message_signature;
 657
 658        return 0;
 659}
 660
 661static int ceph_x_update_authorizer(
 662        struct ceph_auth_client *ac, int peer_type,
 663        struct ceph_auth_handshake *auth)
 664{
 665        struct ceph_x_authorizer *au;
 666        struct ceph_x_ticket_handler *th;
 667
 668        th = get_ticket_handler(ac, peer_type);
 669        if (IS_ERR(th))
 670                return PTR_ERR(th);
 671
 672        au = (struct ceph_x_authorizer *)auth->authorizer;
 673        if (au->secret_id < th->secret_id) {
 674                dout("ceph_x_update_authorizer service %u secret %llu < %llu\n",
 675                     au->service, au->secret_id, th->secret_id);
 676                return ceph_x_build_authorizer(ac, th, au);
 677        }
 678        return 0;
 679}
 680
 681static int decrypt_authorize_challenge(struct ceph_x_authorizer *au,
 682                                       void *challenge_buf,
 683                                       int challenge_buf_len,
 684                                       u64 *server_challenge)
 685{
 686        struct ceph_x_authorize_challenge *ch =
 687            challenge_buf + sizeof(struct ceph_x_encrypt_header);
 688        int ret;
 689
 690        /* no leading len */
 691        ret = __ceph_x_decrypt(&au->session_key, challenge_buf,
 692                               challenge_buf_len);
 693        if (ret < 0)
 694                return ret;
 695        if (ret < sizeof(*ch)) {
 696                pr_err("bad size %d for ceph_x_authorize_challenge\n", ret);
 697                return -EINVAL;
 698        }
 699
 700        *server_challenge = le64_to_cpu(ch->server_challenge);
 701        return 0;
 702}
 703
 704static int ceph_x_add_authorizer_challenge(struct ceph_auth_client *ac,
 705                                           struct ceph_authorizer *a,
 706                                           void *challenge_buf,
 707                                           int challenge_buf_len)
 708{
 709        struct ceph_x_authorizer *au = (void *)a;
 710        u64 server_challenge;
 711        int ret;
 712
 713        ret = decrypt_authorize_challenge(au, challenge_buf, challenge_buf_len,
 714                                          &server_challenge);
 715        if (ret) {
 716                pr_err("failed to decrypt authorize challenge: %d", ret);
 717                return ret;
 718        }
 719
 720        ret = encrypt_authorizer(au, &server_challenge);
 721        if (ret) {
 722                pr_err("failed to encrypt authorizer w/ challenge: %d", ret);
 723                return ret;
 724        }
 725
 726        return 0;
 727}
 728
 729static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac,
 730                                          struct ceph_authorizer *a)
 731{
 732        struct ceph_x_authorizer *au = (void *)a;
 733        void *p = au->enc_buf;
 734        struct ceph_x_authorize_reply *reply = p + ceph_x_encrypt_offset();
 735        int ret;
 736
 737        ret = ceph_x_decrypt(&au->session_key, &p, p + CEPHX_AU_ENC_BUF_LEN);
 738        if (ret < 0)
 739                return ret;
 740        if (ret < sizeof(*reply)) {
 741                pr_err("bad size %d for ceph_x_authorize_reply\n", ret);
 742                return -EINVAL;
 743        }
 744
 745        if (au->nonce + 1 != le64_to_cpu(reply->nonce_plus_one))
 746                ret = -EPERM;
 747        else
 748                ret = 0;
 749        dout("verify_authorizer_reply nonce %llx got %llx ret %d\n",
 750             au->nonce, le64_to_cpu(reply->nonce_plus_one), ret);
 751        return ret;
 752}
 753
 754static void ceph_x_reset(struct ceph_auth_client *ac)
 755{
 756        struct ceph_x_info *xi = ac->private;
 757
 758        dout("reset\n");
 759        xi->starting = true;
 760        xi->server_challenge = 0;
 761}
 762
 763static void ceph_x_destroy(struct ceph_auth_client *ac)
 764{
 765        struct ceph_x_info *xi = ac->private;
 766        struct rb_node *p;
 767
 768        dout("ceph_x_destroy %p\n", ac);
 769        ceph_crypto_key_destroy(&xi->secret);
 770
 771        while ((p = rb_first(&xi->ticket_handlers)) != NULL) {
 772                struct ceph_x_ticket_handler *th =
 773                        rb_entry(p, struct ceph_x_ticket_handler, node);
 774                remove_ticket_handler(ac, th);
 775        }
 776
 777        ceph_x_authorizer_cleanup(&xi->auth_authorizer);
 778
 779        kfree(ac->private);
 780        ac->private = NULL;
 781}
 782
 783static void invalidate_ticket(struct ceph_auth_client *ac, int peer_type)
 784{
 785        struct ceph_x_ticket_handler *th;
 786
 787        th = get_ticket_handler(ac, peer_type);
 788        if (!IS_ERR(th))
 789                th->have_key = false;
 790}
 791
 792static void ceph_x_invalidate_authorizer(struct ceph_auth_client *ac,
 793                                         int peer_type)
 794{
 795        /*
 796         * We are to invalidate a service ticket in the hopes of
 797         * getting a new, hopefully more valid, one.  But, we won't get
 798         * it unless our AUTH ticket is good, so invalidate AUTH ticket
 799         * as well, just in case.
 800         */
 801        invalidate_ticket(ac, peer_type);
 802        invalidate_ticket(ac, CEPH_ENTITY_TYPE_AUTH);
 803}
 804
 805static int calc_signature(struct ceph_x_authorizer *au, struct ceph_msg *msg,
 806                          __le64 *psig)
 807{
 808        void *enc_buf = au->enc_buf;
 809        int ret;
 810
 811        if (!CEPH_HAVE_FEATURE(msg->con->peer_features, CEPHX_V2)) {
 812                struct {
 813                        __le32 len;
 814                        __le32 header_crc;
 815                        __le32 front_crc;
 816                        __le32 middle_crc;
 817                        __le32 data_crc;
 818                } __packed *sigblock = enc_buf + ceph_x_encrypt_offset();
 819
 820                sigblock->len = cpu_to_le32(4*sizeof(u32));
 821                sigblock->header_crc = msg->hdr.crc;
 822                sigblock->front_crc = msg->footer.front_crc;
 823                sigblock->middle_crc = msg->footer.middle_crc;
 824                sigblock->data_crc =  msg->footer.data_crc;
 825
 826                ret = ceph_x_encrypt(&au->session_key, enc_buf,
 827                                     CEPHX_AU_ENC_BUF_LEN, sizeof(*sigblock));
 828                if (ret < 0)
 829                        return ret;
 830
 831                *psig = *(__le64 *)(enc_buf + sizeof(u32));
 832        } else {
 833                struct {
 834                        __le32 header_crc;
 835                        __le32 front_crc;
 836                        __le32 front_len;
 837                        __le32 middle_crc;
 838                        __le32 middle_len;
 839                        __le32 data_crc;
 840                        __le32 data_len;
 841                        __le32 seq_lower_word;
 842                } __packed *sigblock = enc_buf;
 843                struct {
 844                        __le64 a, b, c, d;
 845                } __packed *penc = enc_buf;
 846                int ciphertext_len;
 847
 848                sigblock->header_crc = msg->hdr.crc;
 849                sigblock->front_crc = msg->footer.front_crc;
 850                sigblock->front_len = msg->hdr.front_len;
 851                sigblock->middle_crc = msg->footer.middle_crc;
 852                sigblock->middle_len = msg->hdr.middle_len;
 853                sigblock->data_crc =  msg->footer.data_crc;
 854                sigblock->data_len = msg->hdr.data_len;
 855                sigblock->seq_lower_word = *(__le32 *)&msg->hdr.seq;
 856
 857                /* no leading len, no ceph_x_encrypt_header */
 858                ret = ceph_crypt(&au->session_key, true, enc_buf,
 859                                 CEPHX_AU_ENC_BUF_LEN, sizeof(*sigblock),
 860                                 &ciphertext_len);
 861                if (ret)
 862                        return ret;
 863
 864                *psig = penc->a ^ penc->b ^ penc->c ^ penc->d;
 865        }
 866
 867        return 0;
 868}
 869
 870static int ceph_x_sign_message(struct ceph_auth_handshake *auth,
 871                               struct ceph_msg *msg)
 872{
 873        __le64 sig;
 874        int ret;
 875
 876        if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN))
 877                return 0;
 878
 879        ret = calc_signature((struct ceph_x_authorizer *)auth->authorizer,
 880                             msg, &sig);
 881        if (ret)
 882                return ret;
 883
 884        msg->footer.sig = sig;
 885        msg->footer.flags |= CEPH_MSG_FOOTER_SIGNED;
 886        return 0;
 887}
 888
 889static int ceph_x_check_message_signature(struct ceph_auth_handshake *auth,
 890                                          struct ceph_msg *msg)
 891{
 892        __le64 sig_check;
 893        int ret;
 894
 895        if (ceph_test_opt(from_msgr(msg->con->msgr), NOMSGSIGN))
 896                return 0;
 897
 898        ret = calc_signature((struct ceph_x_authorizer *)auth->authorizer,
 899                             msg, &sig_check);
 900        if (ret)
 901                return ret;
 902        if (sig_check == msg->footer.sig)
 903                return 0;
 904        if (msg->footer.flags & CEPH_MSG_FOOTER_SIGNED)
 905                dout("ceph_x_check_message_signature %p has signature %llx "
 906                     "expect %llx\n", msg, msg->footer.sig, sig_check);
 907        else
 908                dout("ceph_x_check_message_signature %p sender did not set "
 909                     "CEPH_MSG_FOOTER_SIGNED\n", msg);
 910        return -EBADMSG;
 911}
 912
 913static const struct ceph_auth_client_ops ceph_x_ops = {
 914        .name = "x",
 915        .is_authenticated = ceph_x_is_authenticated,
 916        .should_authenticate = ceph_x_should_authenticate,
 917        .build_request = ceph_x_build_request,
 918        .handle_reply = ceph_x_handle_reply,
 919        .create_authorizer = ceph_x_create_authorizer,
 920        .update_authorizer = ceph_x_update_authorizer,
 921        .add_authorizer_challenge = ceph_x_add_authorizer_challenge,
 922        .verify_authorizer_reply = ceph_x_verify_authorizer_reply,
 923        .invalidate_authorizer = ceph_x_invalidate_authorizer,
 924        .reset =  ceph_x_reset,
 925        .destroy = ceph_x_destroy,
 926        .sign_message = ceph_x_sign_message,
 927        .check_message_signature = ceph_x_check_message_signature,
 928};
 929
 930
 931int ceph_x_init(struct ceph_auth_client *ac)
 932{
 933        struct ceph_x_info *xi;
 934        int ret;
 935
 936        dout("ceph_x_init %p\n", ac);
 937        ret = -ENOMEM;
 938        xi = kzalloc(sizeof(*xi), GFP_NOFS);
 939        if (!xi)
 940                goto out;
 941
 942        ret = -EINVAL;
 943        if (!ac->key) {
 944                pr_err("no secret set (for auth_x protocol)\n");
 945                goto out_nomem;
 946        }
 947
 948        ret = ceph_crypto_key_clone(&xi->secret, ac->key);
 949        if (ret < 0) {
 950                pr_err("cannot clone key: %d\n", ret);
 951                goto out_nomem;
 952        }
 953
 954        xi->starting = true;
 955        xi->ticket_handlers = RB_ROOT;
 956
 957        ac->protocol = CEPH_AUTH_CEPHX;
 958        ac->private = xi;
 959        ac->ops = &ceph_x_ops;
 960        return 0;
 961
 962out_nomem:
 963        kfree(xi);
 964out:
 965        return ret;
 966}
 967