ex_next_record: 415| 780|uint16_t ex_next_record(BufCtl* buf, int *length) { 416| 780| uint16_t *ptr = (uint16_t *)buf->next; 417| 780| uint16_t type = ntohs(*ptr++); 418| 780| *length = ntohs(*ptr++)-NTS_KE_HDR_LNG; ------------------ | | 71| 780|#define NTS_KE_HDR_LNG 4 ------------------ 419| 780| buf->next += NTS_KE_HDR_LNG; ------------------ | | 71| 780|#define NTS_KE_HDR_LNG 4 ------------------ 420| 780| buf->left -= NTS_KE_HDR_LNG; ------------------ | | 71| 780|#define NTS_KE_HDR_LNG 4 ------------------ 421| 780| return type; 422| 780|} next_bytes: 434| 355|uint16_t next_bytes(BufCtl* buf, uint8_t *data, int length) { 435| 355| memcpy(data, buf->next, length); 436| 355| buf->next += length; 437| 355| buf->left -= length; 438| 355| return length; 439| 355|} nts_unpack_cookie: 362| 5| uint8_t *c2s, uint8_t *s2c, int *keylen) { 363| 5| uint8_t *finger; 364| 5| uint8_t plaintext[NTS_MAX_COOKIELEN]; 365| 5| uint8_t *nonce; 366| 5| uint32_t temp; 367| 5| size_t plainlength; 368| 5| int cipherlength; 369| 5| bool ok; 370| 5| struct NTS_Key *key; 371| 5| int i; 372| | 373| 5| if (NULL == cookie_ctx) ------------------ | Branch (373:6): [True: 5, False: 0] ------------------ 374| 5| return false; /* We aren't initialized yet. */ 375| | 376| 0| if (0 == nts_nKeys) { ------------------ | Branch (376:6): [True: 0, False: 0] ------------------ 377| 0| nts_cnt.cookie_not_server++; 378| 0| return false; /* We are not a NTS enabled server. */ 379| 0| } 380| | 381| | /* We may get garbage from the net */ 382| 0| if (cookielen > NTS_MAX_COOKIELEN) ------------------ | | 97| 0|#define NTS_MAX_COOKIELEN 192 /* see nts_cookie.c */ ------------------ | Branch (382:6): [True: 0, False: 0] ------------------ 383| 0| return false; 384| | 385| 0| finger = cookie; 386| 0| key = NULL; /* squash uninitialized warning */ 387| 0| for (i=0; iI, sizeof(key->I))) { ------------------ | Branch (389:8): [True: 0, False: 0] ------------------ 390| 0| break; 391| 0| } 392| 0| } 393| 0| nts_cnt.cookie_decode_total++; /* total attempts, includes too old */ 394| 0| if (nts_nKeys == i) { ------------------ | Branch (394:6): [True: 0, False: 0] ------------------ 395| 0| nts_cnt.cookie_decode_too_old++; 396| 0| return false; 397| 0| } 398| 0| if (0 == i) { ------------------ | Branch (398:6): [True: 0, False: 0] ------------------ 399| 0| nts_cnt.cookie_decode_current++; 400| 0| } else if (1 == i) { ------------------ | Branch (400:13): [True: 0, False: 0] ------------------ 401| 0| nts_cnt.cookie_decode_old++; 402| 0| } else if (2 == i) { ------------------ | Branch (402:13): [True: 0, False: 0] ------------------ 403| 0| nts_cnt.cookie_decode_old2++; 404| 0| } else { 405| 0| nts_cnt.cookie_decode_older++; 406| 0| } 407| |#if 0 408| | if (1I); 416| 0| nonce = finger; 417| 0| finger += NONCE_LENGTH; ------------------ | | 168| 0|#define NONCE_LENGTH 16 ------------------ 418| | 419| | // require(AD_LENGTH==finger-cookie); 420| | 421| 0| cipherlength = cookielen - AD_LENGTH; ------------------ | | 109| 0|#define AD_LENGTH 20 ------------------ 422| 0| plainlength = NTS_MAX_COOKIELEN; ------------------ | | 97| 0|#define NTS_MAX_COOKIELEN 192 /* see nts_cookie.c */ ------------------ 423| | 424| 0| nts_lock_cookielock(); 425| | 426| 0| ok = AES_SIV_Decrypt(cookie_ctx, 427| 0| plaintext, &plainlength, 428| 0| key->K, K_length, 429| 0| nonce, NONCE_LENGTH, ------------------ | | 168| 0|#define NONCE_LENGTH 16 ------------------ 430| 0| finger, cipherlength, 431| 0| cookie, AD_LENGTH); ------------------ | | 109| 0|#define AD_LENGTH 20 ------------------ 432| | 433| 0| nts_unlock_cookielock(); 434| | 435| 0| if (!ok) { ------------------ | Branch (435:6): [True: 0, False: 0] ------------------ 436| 0| nts_cnt.cookie_decode_error++; 437| 0| return false; 438| 0| } 439| | 440| 0| *keylen = (plainlength-AEAD_LENGTH)/2; ------------------ | | 110| 0|#define AEAD_LENGTH 4 ------------------ 441| 0| finger = plaintext; 442| 0| memcpy(&temp, finger, AEAD_LENGTH); ------------------ | | 110| 0|#define AEAD_LENGTH 4 ------------------ 443| 0| *aead = temp; 444| 0| finger += AEAD_LENGTH; ------------------ | | 110| 0|#define AEAD_LENGTH 4 ------------------ 445| 0| memcpy(c2s, finger, *keylen); 446| 0| finger += *keylen; 447| 0| memcpy(s2c, finger, *keylen); 448| 0| finger += *keylen; 449| | 450| 0| return true; 451| 0|} extens_server_recv: 120| 169|bool extens_server_recv(struct ntspacket_t *ntspacket, uint8_t *pkt, int lng) { 121| 169| struct BufCtl_t buf; 122| 169| uint16_t aead; 123| 169| int noncelen, cmaclen; 124| 169| bool sawcookie, sawAEEF; 125| 169| int cookielen; /* cookie and placeholder(s) */ 126| | 127| 169| nts_cnt.server_recv_bad++; /* assume bad, undo if OK */ 128| | 129| 169| buf.next = pkt+LEN_PKT_NOMAC; ------------------ | | 376| 169|#define LEN_PKT_NOMAC 48 /* min header length */ ------------------ 130| 169| buf.left = lng-LEN_PKT_NOMAC; ------------------ | | 376| 169|#define LEN_PKT_NOMAC 48 /* min header length */ ------------------ 131| | 132| 169| sawcookie = sawAEEF = false; 133| 169| cookielen = 0; 134| 169| ntspacket->uidlen = 0; 135| 169| ntspacket->needed = 0; 136| | 137| 829| while (buf.left >= NTS_KE_HDR_LNG) { ------------------ | | 71| 829|#define NTS_KE_HDR_LNG 4 ------------------ | Branch (137:9): [True: 780, False: 49] ------------------ 138| 780| uint16_t type; 139| 780| bool critical = false; 140| 780| int length, adlength; 141| 780| size_t outlen; 142| 780| uint8_t *nonce, *cmac; 143| 780| bool ok; 144| | 145| 780| type = ex_next_record(&buf, &length); /* length excludes header */ 146| 780| if (length&3 || length > buf.left || length < 0) { ------------------ | Branch (146:7): [True: 8, False: 772] | Branch (146:19): [True: 22, False: 750] | Branch (146:40): [True: 14, False: 736] ------------------ 147| 44| return false; 148| 44| } 149| 736| if (NTS_CRITICAL & type) { ------------------ | | 172| 736|#define NTS_CRITICAL 0x8000 ------------------ | Branch (149:7): [True: 266, False: 470] ------------------ 150| 266| critical = true; 151| 266| type &= ~NTS_CRITICAL; ------------------ | | 172| 266|#define NTS_CRITICAL 0x8000 ------------------ 152| 266| } 153| 736| switch (type) { 154| 361| case Unique_Identifier: ------------------ | Branch (154:7): [True: 361, False: 375] ------------------ 155| 361| if (length > NTS_UID_MAX_LENGTH) { ------------------ | | 100| 361|#define NTS_UID_MAX_LENGTH 64 ------------------ | Branch (155:8): [True: 6, False: 355] ------------------ 156| 6| return false; 157| 6| } 158| 355| ntspacket->uidlen = length; 159| 355| next_bytes(&buf, ntspacket->UID, length); 160| 355| break; 161| 21| case NTS_Cookie: ------------------ | Branch (161:7): [True: 21, False: 715] ------------------ 162| | /* cookies and placeholders must be the same length 163| | * in order to avoid amplification attacks. 164| | */ 165| 21| if (sawcookie) { ------------------ | Branch (165:8): [True: 0, False: 21] ------------------ 166| 0| return false; /* second cookie */ 167| 0| } 168| 21| if (0 == cookielen) { ------------------ | Branch (168:8): [True: 4, False: 17] ------------------ 169| 4| cookielen = length; 170| 4| } 171| 17| else if (length != cookielen) { ------------------ | Branch (171:13): [True: 16, False: 1] ------------------ 172| 16| return false; 173| 16| } 174| 5| ok = nts_unpack_cookie(buf.next, length, &aead, ntspacket->c2s, 175| 5| ntspacket->s2c, &ntspacket->keylen); 176| 5| if (!ok) { ------------------ | Branch (176:8): [True: 5, False: 0] ------------------ 177| 5| return false; 178| 5| } 179| 0| buf.next += length; 180| 0| buf.left -= length; 181| 0| sawcookie = true; 182| 0| ntspacket->needed++; 183| 0| ntspacket->aead = aead; 184| 0| break; 185| 321| case NTS_Cookie_Placeholder: ------------------ | Branch (185:7): [True: 321, False: 415] ------------------ 186| 321| if (0 == cookielen) { ------------------ | Branch (186:8): [True: 239, False: 82] ------------------ 187| 239| cookielen = length; 188| 239| } 189| 82| else if (length != cookielen) { ------------------ | Branch (189:13): [True: 16, False: 66] ------------------ 190| 16| return false; 191| 16| } 192| 305| ntspacket->needed++; 193| 305| buf.next += length; 194| 305| buf.left -= length; 195| 305| break; 196| 1| case NTS_AEEF: ------------------ | Branch (196:7): [True: 1, False: 735] ------------------ 197| 1| if (!sawcookie) { ------------------ | Branch (197:8): [True: 1, False: 0] ------------------ 198| 1| return false; /* no cookie yet, no c2s */ 199| 1| } 200| 0| if (length != NTP_EX_HDR_LNG+NONCE_LENGTH+CMAC_LENGTH) { ------------------ | | 32| 0|#define NTP_EX_HDR_LNG 4 ------------------ if (length != NTP_EX_HDR_LNG+NONCE_LENGTH+CMAC_LENGTH) { ------------------ | | 29| 0|#define NONCE_LENGTH 16 ------------------ if (length != NTP_EX_HDR_LNG+NONCE_LENGTH+CMAC_LENGTH) { ------------------ | | 30| 0|#define CMAC_LENGTH 16 ------------------ | Branch (200:8): [True: 0, False: 0] ------------------ 201| 0| return false; 202| 0| } 203| | /* Additional data is up to this exten. */ 204| | /* backup over header */ 205| 0| adlength = buf.next-NTP_EX_HDR_LNG-pkt; ------------------ | | 32| 0|#define NTP_EX_HDR_LNG 4 ------------------ 206| 0| noncelen = next_uint16(&buf); 207| 0| cmaclen = next_uint16(&buf); 208| 0| if (noncelen & 3) { ------------------ | Branch (208:8): [True: 0, False: 0] ------------------ 209| 0| return false; /* would require padding */ 210| 0| } 211| 0| if (CMAC_LENGTH != cmaclen) { ------------------ | | 30| 0|#define CMAC_LENGTH 16 ------------------ | Branch (211:8): [True: 0, False: 0] ------------------ 212| 0| return false; 213| 0| } 214| 0| nonce = buf.next; 215| 0| cmac = nonce+NONCE_LENGTH; ------------------ | | 29| 0|#define NONCE_LENGTH 16 ------------------ 216| 0| outlen = 6; 217| 0| ok = AES_SIV_Decrypt(wire_ctx, 218| 0| NULL, &outlen, 219| 0| ntspacket->c2s, ntspacket->keylen, 220| 0| nonce, noncelen, 221| 0| cmac, CMAC_LENGTH, ------------------ | | 30| 0|#define CMAC_LENGTH 16 ------------------ 222| 0| pkt, adlength); 223| 0| if (!ok) { ------------------ | Branch (223:8): [True: 0, False: 0] ------------------ 224| 0| return false; 225| 0| } 226| 0| if (0 != outlen) { ------------------ | Branch (226:8): [True: 0, False: 0] ------------------ 227| 0| return false; 228| 0| } 229| | /* we already used 2 length slots way above*/ 230| 0| length -= (NTP_EX_U16_LNG+NTP_EX_U16_LNG); ------------------ | | 33| 0|#define NTP_EX_U16_LNG 2 ------------------ length -= (NTP_EX_U16_LNG+NTP_EX_U16_LNG); ------------------ | | 33| 0|#define NTP_EX_U16_LNG 2 ------------------ 231| 0| buf.next += length; 232| 0| buf.left -= length; 233| 0| if (0 != buf.left) { ------------------ | Branch (233:8): [True: 0, False: 0] ------------------ 234| 0| return false; /* Reject extens after AEEF block */ 235| 0| } 236| 0| sawAEEF = true; 237| 0| break; 238| 32| default: ------------------ | Branch (238:7): [True: 32, False: 704] ------------------ 239| | /* Non NTS extensions on requests at server. 240| | * Call out when we get some that we want. 241| | * Until then, it's probably a bug. */ 242| 32| if (critical) { ------------------ | Branch (242:8): [True: 26, False: 6] ------------------ 243| 26| return false; 244| 26| } 245| 6| buf.next += length; 246| 6| buf.left -= length; 247| 6| return false; 248| 736| } 249| 736| } 250| | 251| 49| if (!sawAEEF) { ------------------ | Branch (251:6): [True: 49, False: 0] ------------------ 252| 49| return false; 253| 49| } 254| 0| if (buf.left > 0) ------------------ | Branch (254:6): [True: 0, False: 0] ------------------ 255| 0| return false; 256| | 257| | // printf("ESRx: %d, %d, %d\n", 258| | // lng-LEN_PKT_NOMAC, ntspacket->needed, ntspacket->keylen); 259| 0| ntspacket->valid = true; 260| 0| nts_cnt.server_recv_good++; 261| 0| nts_cnt.server_recv_bad--; 262| 0| return true; 263| 0|} LLVMFuzzerTestOneInput: 22| 201|extern int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {//ntpsec/tests/ntpd/nts_extens.c 23| | 24| 201| if (Size < kMinInputLength || Size > kMaxInputLength){ ------------------ | | 19| 402|#define kMinInputLength 20 ------------------ if (Size < kMinInputLength || Size > kMaxInputLength){ ------------------ | | 20| 193|#define kMaxInputLength 1024 ------------------ | Branch (24:6): [True: 8, False: 193] | Branch (24:32): [True: 24, False: 169] ------------------ 25| 32| return 0; 26| 32| } 27| | 28| 169| struct ntspacket_t ntspkt; 29| 169| memset(&ntspkt, 0, sizeof(ntspkt)); 30| | 31| 169| return extens_server_recv(&ntspkt,(uint8_t*)Data, Size); 32| 201|}