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