1 /*
2  * Copyright (C) 2021 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <nfc_int.h>
18 #include <rw_int.h>
19 #include <dlfcn.h>
20 #include <unistd.h>
21 
22 #include "../includes/common.h"
23 #include "../includes/memutils.h"
24 
25 #define T3T_MSG_FELICALITE_MC_OFFSET 0x01
26 
27 char enable_selective_overload = ENABLE_NONE;
28 char *vulnPtr = nullptr;
29 
30 bool testInProgress = false;
31 struct sigaction new_action, old_action;
sigsegv_handler(int signum,siginfo_t * info,void * context)32 void sigsegv_handler(int signum, siginfo_t *info, void* context) {
33     if (testInProgress && info->si_signo == SIGSEGV) {
34         const size_t page_size = getpagesize();
35         const size_t page_mask = (~(page_size - 1));
36         if (page_size) {
37             char *vulnPtrGuardPage = (char *) ((size_t) vulnPtr & page_mask) + page_size;
38             char *faultPage = (char *) ((size_t) info->si_addr & page_mask);
39             if (faultPage == vulnPtrGuardPage) {
40                 (*old_action.sa_sigaction)(signum, info, context);
41                 return;
42             }
43         }
44     }
45     _exit(EXIT_FAILURE);
46 }
47 
48 extern tRW_CB rw_cb;
49 extern tNFC_CB nfc_cb;
50 void rw_init(void);
51 tNFC_STATUS rw_t3t_select(uint8_t peer_nfcid2[NCI_RF_F_UID_LEN],
52                           uint8_t mrti_check, uint8_t mrti_update);
53 
54 static void (*real_GKI_freebuf)(void* ptr) = nullptr;
55 void *kAllocatedPointers[2];
56 int allocatedPointersIndex = -1;
57 bool kIsInitialized = false;
58 
init(void)59 void init(void) {
60     real_GKI_freebuf = (void (*)(void*))dlsym(RTLD_NEXT, "_Z11GKI_freebufPv");
61     if (!real_GKI_freebuf) {
62         return;
63     }
64 
65     kIsInitialized = true;
66 }
67 
GKI_freebuf(void * ptr)68 void GKI_freebuf(void* ptr) {
69     if (!kIsInitialized) {
70         init();
71     }
72     if (ptr == kAllocatedPointers[0] || ptr == kAllocatedPointers[1]) {
73         return;
74     } else {
75         real_GKI_freebuf(ptr);
76     }
77 }
78 
allocate_memory(size_t size)79 void *allocate_memory(size_t size) {
80     void *ptr = memalign(16, size);
81     memset(ptr, 0x0, size);
82     kAllocatedPointers[++allocatedPointersIndex] = ptr;
83     return ptr;
84 }
85 
86 // borrowed from rw_i93.cc
87 enum {
88     RW_T3T_CMD_DETECT_NDEF,
89     RW_T3T_CMD_CHECK_NDEF,
90     RW_T3T_CMD_UPDATE_NDEF,
91     RW_T3T_CMD_CHECK,
92     RW_T3T_CMD_UPDATE,
93     RW_T3T_CMD_SEND_RAW_FRAME,
94     RW_T3T_CMD_GET_SYSTEM_CODES,
95     RW_T3T_CMD_FORMAT,
96     RW_T3T_CMD_SET_READ_ONLY_SOFT,
97     RW_T3T_CMD_SET_READ_ONLY_HARD,
98 
99     RW_T3T_CMD_MAX
100 };
101 
102 // borrowed from rw_i93.cc
103 enum {
104     RW_T3T_STATE_NOT_ACTIVATED,
105     RW_T3T_STATE_IDLE,
106     RW_T3T_STATE_COMMAND_PENDING
107 };
108 
109 // borrowed from rw_i93.cc
110 enum {
111     /* Sub states for formatting Felica-Lite */
112     RW_T3T_FMT_SST_POLL_FELICA_LITE, /* Waiting for POLL Felica-Lite response (for
113      formatting) */
114     RW_T3T_FMT_SST_CHECK_MC_BLK, /* Waiting for Felica-Lite MC (MemoryControl)
115      block-read to complete */
116     RW_T3T_FMT_SST_UPDATE_MC_BLK, /* Waiting for Felica-Lite MC (MemoryControl)
117      block-write to complete */
118     RW_T3T_FMT_SST_UPDATE_NDEF_ATTRIB, /* Waiting for NDEF attribute block-write
119      to complete */
120 
121     /* Sub states for setting Felica-Lite read only */
122     RW_T3T_SRO_SST_POLL_FELICA_LITE, /* Waiting for POLL Felica-Lite response (for
123      setting read only) */
124     RW_T3T_SRO_SST_UPDATE_NDEF_ATTRIB, /* Waiting for NDEF attribute block-write
125      to complete */
126     RW_T3T_SRO_SST_CHECK_MC_BLK, /* Waiting for Felica-Lite MC (MemoryControl)
127      block-read to complete */
128     RW_T3T_SRO_SST_UPDATE_MC_BLK /* Waiting for Felica-Lite MC (MemoryControl)
129      block-write to complete */
130 };
131 
cback(tRW_EVENT event,tRW_DATA * p_data)132 void cback(tRW_EVENT event __attribute__((unused)),
133            tRW_DATA* p_data __attribute__((unused))) {
134 }
135 
main()136 int main() {
137     sigemptyset(&new_action.sa_mask);
138     new_action.sa_flags = SA_SIGINFO;
139     new_action.sa_sigaction = sigsegv_handler;
140     sigaction(SIGSEGV, &new_action, &old_action);
141     tRW_T3T_CB* p_t3t = &rw_cb.tcb.t3t;
142 
143     GKI_init();
144     rw_init();
145 
146     uint8_t peer_nfcid2[NCI_RF_F_UID_LEN];
147     uint8_t mrti_check = 1, mrti_update = 1;
148     enable_selective_overload = ENABLE_MEMALIGN_CHECK;
149     if (rw_t3t_select(peer_nfcid2, mrti_check, mrti_update) != NFC_STATUS_OK) {
150         return EXIT_FAILURE;
151     }
152 
153     tNFC_CONN *p_data = (tNFC_CONN *) allocate_memory(sizeof(tNFC_CONN));
154     if (!p_data) {
155         return EXIT_FAILURE;
156     }
157     p_data->data.p_data = (NFC_HDR *) allocate_memory(sizeof(NFC_HDR) * 4);
158     enable_selective_overload = ENABLE_FREE_CHECK | ENABLE_REALLOC_CHECK;
159     if (!(p_data->data.p_data)) {
160         free(p_data);
161         return EXIT_FAILURE;
162     }
163     vulnPtr = (char *)p_data->data.p_data;
164     p_data->status = NFC_STATUS_OK;
165 
166     p_t3t->cur_cmd = RW_T3T_CMD_SET_READ_ONLY_HARD;
167     p_t3t->rw_state = RW_T3T_STATE_COMMAND_PENDING;
168     p_t3t->rw_substate = RW_T3T_SRO_SST_CHECK_MC_BLK;
169 
170     NFC_HDR* p_msg = (p_data->data).p_data;
171     p_msg->len = T3T_MSG_RSP_COMMON_HDR_LEN;
172 
173     uint8_t* p_t3t_rsp = (uint8_t*) (p_msg + 1) + (p_msg->offset + 1);
174     p_t3t_rsp[T3T_MSG_RSP_OFFSET_RSPCODE] = T3T_MSG_OPC_CHECK_RSP;
175     p_t3t_rsp[T3T_MSG_RSP_OFFSET_STATUS1] = T3T_MSG_RSP_STATUS_OK;
176 
177     uint8_t* p_mc = &p_t3t_rsp[T3T_MSG_RSP_OFFSET_CHECK_DATA];
178     p_mc[T3T_MSG_FELICALITE_MC_OFFSET_SYS_OP] = T3T_MSG_FELICALITE_MC_OFFSET;
179 
180     tNFC_CONN_CB* p_cb = &nfc_cb.conn_cb[NFC_RF_CONN_ID];
181     tNFC_CONN_EVT event = NFC_DATA_CEVT;
182     TIMER_LIST_ENT pFirst = { };
183     nfc_cb.quick_timer_queue.p_first = &pFirst;
184 
185     rw_cb.p_cback = &cback;
186     testInProgress = true;
187     p_cb->p_cback(0, event, p_data);
188     testInProgress = false;
189 
190     free(p_data->data.p_data);
191     free(p_data);
192 
193     return EXIT_SUCCESS;
194 }
195