1 /* 2 * gdbstub internals 3 * 4 * Copyright (c) 2022 Linaro Ltd 5 * 6 * SPDX-License-Identifier: GPL-2.0-or-later 7 */ 8 9 #ifndef GDBSTUB_INTERNALS_H 10 #define GDBSTUB_INTERNALS_H 11 12 #include "exec/cpu-common.h" 13 14 #define MAX_PACKET_LENGTH 4096 15 16 /* 17 * Shared structures and definitions 18 */ 19 20 enum { 21 GDB_SIGNAL_0 = 0, 22 GDB_SIGNAL_INT = 2, 23 GDB_SIGNAL_QUIT = 3, 24 GDB_SIGNAL_TRAP = 5, 25 GDB_SIGNAL_ABRT = 6, 26 GDB_SIGNAL_ALRM = 14, 27 GDB_SIGNAL_STOP = 17, 28 GDB_SIGNAL_IO = 23, 29 GDB_SIGNAL_XCPU = 24, 30 GDB_SIGNAL_UNKNOWN = 143 31 }; 32 33 typedef struct GDBProcess { 34 uint32_t pid; 35 bool attached; 36 char *target_xml; 37 } GDBProcess; 38 39 enum RSState { 40 RS_INACTIVE, 41 RS_IDLE, 42 RS_GETLINE, 43 RS_GETLINE_ESC, 44 RS_GETLINE_RLE, 45 RS_CHKSUM1, 46 RS_CHKSUM2, 47 }; 48 49 typedef struct GDBState { 50 bool init; /* have we been initialised? */ 51 CPUState *c_cpu; /* current CPU for step/continue ops */ 52 CPUState *g_cpu; /* current CPU for other ops */ 53 CPUState *query_cpu; /* for q{f|s}ThreadInfo */ 54 enum RSState state; /* parsing state */ 55 char line_buf[MAX_PACKET_LENGTH]; 56 int line_buf_index; 57 int line_sum; /* running checksum */ 58 int line_csum; /* checksum at the end of the packet */ 59 GByteArray *last_packet; 60 int signal; 61 bool multiprocess; 62 GDBProcess *processes; 63 int process_num; 64 GString *str_buf; 65 GByteArray *mem_buf; 66 int sstep_flags; 67 int supported_sstep_flags; 68 /* 69 * Whether we are allowed to send a stop reply packet at this moment. 70 * Must be set off after sending the stop reply itself. 71 */ 72 bool allow_stop_reply; 73 } GDBState; 74 75 /* lives in main gdbstub.c */ 76 extern GDBState gdbserver_state; 77 78 /* 79 * Inline utility function, convert from int to hex and back 80 */ 81 82 static inline int fromhex(int v) 83 { 84 if (v >= '0' && v <= '9') { 85 return v - '0'; 86 } else if (v >= 'A' && v <= 'F') { 87 return v - 'A' + 10; 88 } else if (v >= 'a' && v <= 'f') { 89 return v - 'a' + 10; 90 } else { 91 return 0; 92 } 93 } 94 95 static inline int tohex(int v) 96 { 97 if (v < 10) { 98 return v + '0'; 99 } else { 100 return v - 10 + 'a'; 101 } 102 } 103 104 /* 105 * Connection helpers for both system and user backends 106 */ 107 108 void gdb_put_strbuf(void); 109 int gdb_put_packet(const char *buf); 110 int gdb_put_packet_binary(const char *buf, int len, bool dump); 111 void gdb_hextomem(GByteArray *mem, const char *buf, int len); 112 void gdb_memtohex(GString *buf, const uint8_t *mem, int len); 113 void gdb_memtox(GString *buf, const char *mem, int len); 114 void gdb_read_byte(uint8_t ch); 115 116 /* 117 * Packet acknowledgement - we handle this slightly differently 118 * between user and system mode, mainly to deal with the differences 119 * between the flexible chardev and the direct fd approaches. 120 * 121 * We currently don't support a negotiated QStartNoAckMode 122 */ 123 124 /** 125 * gdb_got_immediate_ack() - check ok to continue 126 * 127 * Returns true to continue, false to re-transmit for user only, the 128 * system stub always returns true. 129 */ 130 bool gdb_got_immediate_ack(void); 131 /* utility helpers */ 132 GDBProcess *gdb_get_process(uint32_t pid); 133 CPUState *gdb_get_first_cpu_in_process(GDBProcess *process); 134 CPUState *gdb_first_attached_cpu(void); 135 void gdb_append_thread_id(CPUState *cpu, GString *buf); 136 int gdb_get_cpu_index(CPUState *cpu); 137 unsigned int gdb_get_max_cpus(void); /* both */ 138 bool gdb_can_reverse(void); /* system emulation, stub for user */ 139 int gdb_target_sigtrap(void); /* user */ 140 141 void gdb_create_default_process(GDBState *s); 142 143 /* signal mapping, common for system, specialised for user-mode */ 144 int gdb_signal_to_target(int sig); 145 int gdb_target_signal_to_gdb(int sig); 146 147 int gdb_get_char(void); /* user only */ 148 149 /** 150 * gdb_continue() - handle continue in mode specific way. 151 */ 152 void gdb_continue(void); 153 154 /** 155 * gdb_continue_partial() - handle partial continue in mode specific way. 156 */ 157 int gdb_continue_partial(char *newstates); 158 159 /* 160 * Helpers with separate system and user implementations 161 */ 162 void gdb_put_buffer(const uint8_t *buf, int len); 163 164 /* 165 * Command handlers - either specialised or system or user only 166 */ 167 void gdb_init_gdbserver_state(void); 168 169 typedef enum GDBThreadIdKind { 170 GDB_ONE_THREAD = 0, 171 GDB_ALL_THREADS, /* One process, all threads */ 172 GDB_ALL_PROCESSES, 173 GDB_READ_THREAD_ERR 174 } GDBThreadIdKind; 175 176 typedef union GdbCmdVariant { 177 const char *data; 178 uint8_t opcode; 179 unsigned long val_ul; 180 unsigned long long val_ull; 181 struct { 182 GDBThreadIdKind kind; 183 uint32_t pid; 184 uint32_t tid; 185 } thread_id; 186 } GdbCmdVariant; 187 188 #define get_param(p, i) (&g_array_index(p, GdbCmdVariant, i)) 189 190 void gdb_handle_query_rcmd(GArray *params, void *ctx); /* system */ 191 void gdb_handle_query_offsets(GArray *params, void *user_ctx); /* user */ 192 void gdb_handle_query_xfer_auxv(GArray *params, void *user_ctx); /*user */ 193 void gdb_handle_query_xfer_siginfo(GArray *params, void *user_ctx); /*user */ 194 void gdb_handle_v_file_open(GArray *params, void *user_ctx); /* user */ 195 void gdb_handle_v_file_close(GArray *params, void *user_ctx); /* user */ 196 void gdb_handle_v_file_pread(GArray *params, void *user_ctx); /* user */ 197 void gdb_handle_v_file_readlink(GArray *params, void *user_ctx); /* user */ 198 void gdb_handle_query_xfer_exec_file(GArray *params, void *user_ctx); /* user */ 199 void gdb_handle_set_catch_syscalls(GArray *params, void *user_ctx); /* user */ 200 void gdb_handle_query_supported_user(const char *gdb_supported); /* user */ 201 bool gdb_handle_set_thread_user(uint32_t pid, uint32_t tid); /* user */ 202 bool gdb_handle_detach_user(uint32_t pid); /* user */ 203 204 void gdb_handle_query_attached(GArray *params, void *ctx); /* both */ 205 206 /* system only */ 207 void gdb_handle_query_qemu_phy_mem_mode(GArray *params, void *ctx); 208 void gdb_handle_set_qemu_phy_mem_mode(GArray *params, void *ctx); 209 210 /* sycall handling */ 211 void gdb_handle_file_io(GArray *params, void *user_ctx); 212 bool gdb_handled_syscall(void); 213 void gdb_disable_syscalls(void); 214 void gdb_syscall_reset(void); 215 216 /* user/system specific syscall handling */ 217 void gdb_syscall_handling(const char *syscall_packet); 218 219 /* 220 * Break/Watch point support - there is an implementation for system 221 * and user mode. 222 */ 223 bool gdb_supports_guest_debug(void); 224 int gdb_breakpoint_insert(CPUState *cs, int type, vaddr addr, vaddr len); 225 int gdb_breakpoint_remove(CPUState *cs, int type, vaddr addr, vaddr len); 226 void gdb_breakpoint_remove_all(CPUState *cs); 227 228 /** 229 * gdb_target_memory_rw_debug() - handle debug access to memory 230 * @cs: CPUState 231 * @addr: nominal address, could be an entire physical address 232 * @buf: data 233 * @len: length of access 234 * @is_write: is it a write operation 235 * 236 * This function is specialised depending on the mode we are running 237 * in. For system guests we can switch the interpretation of the 238 * address to a physical address. 239 */ 240 int gdb_target_memory_rw_debug(CPUState *cs, hwaddr addr, 241 uint8_t *buf, int len, bool is_write); 242 243 #endif /* GDBSTUB_INTERNALS_H */ 244