/*************************************************************************** * Copyright (C) 2005 by Dominic Rath * * Dominic.Rath@gmx.de * * * * This program is free software; you can redistribute it and/or modify * * it under the terms of the GNU General Public License as published by * * the Free Software Foundation; either version 2 of the License, or * * (at your option) any later version. * * * * This program is distributed in the hope that it will be useful, * * but WITHOUT ANY WARRANTY; without even the implied warranty of * * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * * GNU General Public License for more details. * * * * You should have received a copy of the GNU General Public License * * along with this program; if not, write to the * * Free Software Foundation, Inc., * * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * ***************************************************************************/ #include "config.h" #include "gdb_server.h" #include "server.h" #include "log.h" #include "binarybuffer.h" #include "breakpoints.h" #define __USE_GNU #include #include #include #include // -ino: 060521-1116 #ifndef HAVE_STRNDUP #include char * strndup(char * str, int n) { unsigned char * tmp = malloc((size_t)n+1); if (! tmp) perror("gdb_server malloc failed"); if (strlcpy(tmp, str, n) > n) perror("gdb_server strndup: too long"); return tmp; } #endif #if 0 #define _DEBUG_GDB_IO_ #endif static unsigned short gdb_port; int gdb_last_signal(target_t *target) { switch (target->debug_reason) { case DBG_REASON_DBGRQ: return 0x2; /* SIGINT */ case DBG_REASON_BREAKPOINT: case DBG_REASON_WATCHPOINT: case DBG_REASON_WPTANDBKPT: return 0x05; /* SIGTRAP */ case DBG_REASON_SINGLESTEP: return 0x05; /* SIGTRAP */ case DBG_REASON_NOTHALTED: return 0x0; /* no signal... shouldn't happen */ default: ERROR("BUG: undefined debug reason"); exit(-1); } } int gdb_get_char(connection_t *connection, int* next_char) { gdb_connection_t *gdb_con = connection->priv; char *debug_buffer; if (gdb_con->buf_cnt-- > 0) { *next_char = *(gdb_con->buf_p++); if (gdb_con->buf_cnt > 0) connection->input_pending = 1; else connection->input_pending = 0; #ifdef _DEBUG_GDB_IO_ DEBUG("returned char '%c' (0x%2.2x)", *next_char, *next_char); #endif return ERROR_OK; } while ((gdb_con->buf_cnt = read(connection->fd, gdb_con->buffer, GDB_BUFFER_SIZE)) <= 0) { if (gdb_con->buf_cnt == 0) return ERROR_SERVER_REMOTE_CLOSED; switch(errno) { case EAGAIN: usleep(1000); break; case ECONNABORTED: return ERROR_SERVER_REMOTE_CLOSED; case ECONNRESET: return ERROR_SERVER_REMOTE_CLOSED; default: ERROR("read: %s", strerror(errno)); exit(-1); } } debug_buffer = malloc(gdb_con->buf_cnt + 1); memcpy(debug_buffer, gdb_con->buffer, gdb_con->buf_cnt); debug_buffer[gdb_con->buf_cnt] = 0; DEBUG("received '%s'", debug_buffer); free(debug_buffer); gdb_con->buf_p = gdb_con->buffer; gdb_con->buf_cnt--; *next_char = *(gdb_con->buf_p++); if (gdb_con->buf_cnt > 0) connection->input_pending = 1; else connection->input_pending = 0; #ifdef _DEBUG_GDB_IO_ DEBUG("returned char '%c' (0x%2.2x)", *next_char, *next_char); #endif return ERROR_OK; } int gdb_put_packet(connection_t *connection, char *buffer, int len) { int i; unsigned char my_checksum = 0; char checksum[3]; char *debug_buffer; int reply; int retval; gdb_connection_t *gdb_con = connection->priv; for (i = 0; i < len; i++) my_checksum += buffer[i]; while (1) { debug_buffer = malloc(len + 1); memcpy(debug_buffer, buffer, len); debug_buffer[len] = 0; DEBUG("sending packet '$%s#%2.2x'", debug_buffer, my_checksum); free(debug_buffer); write(connection->fd, "$", 1); if (len > 0) write(connection->fd, buffer, len); write(connection->fd, "#", 1); snprintf(checksum, 3, "%2.2x", my_checksum); write(connection->fd, checksum, 2); if ((retval = gdb_get_char(connection, &reply)) != ERROR_OK) return retval; if (reply == '+') break; else if (reply == '-') WARNING("negative reply, retrying"); else if (reply == 0x3) { gdb_con->ctrl_c = 1; if ((retval = gdb_get_char(connection, &reply)) != ERROR_OK) return retval; if (reply == '+') break; else if (reply == '-') WARNING("negative reply, retrying"); else { ERROR("unknown character 0x%2.2x in reply, dropping connection", reply); return ERROR_SERVER_REMOTE_CLOSED; } } else { ERROR("unknown character 0x%2.2x in reply, dropping connection", reply); return ERROR_SERVER_REMOTE_CLOSED; } } return ERROR_OK; } int gdb_get_packet(connection_t *connection, char *buffer, int *len) { int character; int count = 0; int retval; int first_char = 0; int packet_type; char checksum[3]; unsigned char my_checksum = 0; gdb_connection_t *gdb_con = connection->priv; while (1) { do { if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) return retval; switch (character) { case '$': break; case '+': WARNING("acknowledgment received, but no packet pending"); break; case '-': WARNING("negative acknowledgment, but no packet pending"); break; case 0x3: gdb_con->ctrl_c = 1; *len = 0; return ERROR_OK; default: WARNING("ignoring character 0x%x", character); break; } } while (character != '$'); my_checksum = 0; do { if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) return retval; if( !first_char ) { packet_type = character; first_char = 1; } if( packet_type == 'X' ) { switch (character) { case '#': break; case 0x7d: /* data transmitted in binary mode (X packet) * uses 0x7d as escape character */ my_checksum += character & 0xff; gdb_get_char(connection, &character); my_checksum += character & 0xff; buffer[count++] = (character ^ 0x20) & 0xff; if (count > *len) { ERROR("packet buffer too small"); return ERROR_GDB_BUFFER_TOO_SMALL; } break; default: buffer[count++] = character & 0xff; my_checksum += character & 0xff; if (count > *len) { ERROR("packet buffer too small"); return ERROR_GDB_BUFFER_TOO_SMALL; } break; } } else { switch (character) { case '#': break; case 0x3: gdb_con->ctrl_c = 1; break; default: buffer[count++] = character & 0xff; my_checksum += character & 0xff; if (count > *len) { ERROR("packet buffer too small"); return ERROR_GDB_BUFFER_TOO_SMALL; } break; } } } while (character != '#'); *len = count; if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) return retval; checksum[0] = character; if ((retval = gdb_get_char(connection, &character)) != ERROR_OK) return retval; checksum[1] = character; checksum[2] = 0; if (my_checksum == strtoul(checksum, NULL, 16)) { write (connection->fd, "+", 1); break; } WARNING("checksum error, requesting retransmission"); write(connection->fd, "-", 1); } return ERROR_OK; } int gdb_output(struct command_context_s *context, char* line) { connection_t *connection = context->output_handler_priv; char *hex_buffer; int i, bin_size; bin_size = strlen(line); hex_buffer = malloc(bin_size*2 + 4); hex_buffer[0] = 'O'; for (i=0; ipriv; char sig_reply[4]; int signal; switch (event) { case TARGET_EVENT_HALTED: if (gdb_connection->frontend_state == TARGET_RUNNING) { if (gdb_connection->ctrl_c) { signal = 0x2; gdb_connection->ctrl_c = 0; } else { signal = gdb_last_signal(target); } snprintf(sig_reply, 4, "T%2.2x", signal); gdb_put_packet(connection, sig_reply, 3); gdb_connection->frontend_state = TARGET_HALTED; } break; case TARGET_EVENT_RESUMED: if (gdb_connection->frontend_state == TARGET_HALTED) { gdb_connection->frontend_state = TARGET_RUNNING; } break; default: break; } return ERROR_OK; } int gdb_new_connection(connection_t *connection) { gdb_connection_t *gdb_connection = malloc(sizeof(gdb_connection_t)); gdb_service_t *gdb_service = connection->service->priv; int retval; int initial_ack; connection->priv = gdb_connection; /* initialize gdb connection information */ gdb_connection->buf_p = gdb_connection->buffer; gdb_connection->buf_cnt = 0; gdb_connection->ctrl_c = 0; gdb_connection->frontend_state = TARGET_HALTED; /* output goes through gdb connection */ command_set_output_handler(connection->cmd_ctx, gdb_output, connection); /* register callback to be informed about target events */ target_register_event_callback(gdb_target_callback_event_handler, connection); /* a gdb session just attached, put the target in halt mode */ if (((retval = gdb_service->target->type->halt(gdb_service->target)) != ERROR_OK) && (retval != ERROR_TARGET_ALREADY_HALTED)) { ERROR("error when trying to halt target"); exit(-1); } while (gdb_service->target->state != TARGET_HALTED) { gdb_service->target->type->poll(gdb_service->target); } /* remove the initial ACK from the incoming buffer */ if ((retval = gdb_get_char(connection, &initial_ack)) != ERROR_OK) return retval; return ERROR_OK; } int gdb_connection_closed(connection_t *connection) { if (connection->priv) free(connection->priv); else ERROR("BUG: connection->priv == NULL"); target_unregister_event_callback(gdb_target_callback_event_handler, connection); return ERROR_OK; } int gdb_last_signal_packet(connection_t *connection, target_t *target, char* packet, int packet_size) { char sig_reply[4]; int signal; signal = gdb_last_signal(target); snprintf(sig_reply, 4, "S%2.2x", signal); gdb_put_packet(connection, sig_reply, 3); return ERROR_OK; } void gdb_get_registers_packet(connection_t *connection, target_t *target, char* packet, int packet_size) { reg_t **reg_list; int reg_list_size; int retval; int reg_packet_size = 0; char *reg_packet; char *reg_packet_p; int i; DEBUG(""); if ((retval = target->type->get_gdb_reg_list(target, ®_list, ®_list_size)) != ERROR_OK) { switch (retval) { case ERROR_TARGET_NOT_HALTED: ERROR("gdb requested registers, but we're not halted"); exit(-1); default: ERROR("BUG: unexpected error returned by get_gdb_reg_list()"); exit(-1); } } for (i = 0; i < reg_list_size; i++) { reg_packet_size += reg_list[i]->size; } reg_packet = malloc(CEIL(reg_packet_size, 8) * 2); reg_packet_p = reg_packet; for (i = 0; i < reg_list_size; i++) { int j; char *hex_buf = buf_to_char(reg_list[i]->value, reg_list[i]->size); DEBUG("hex_buf: %s", hex_buf); for (j = CEIL(reg_list[i]->size, 8) * 2; j > 0; j -= 2) { *reg_packet_p++ = hex_buf[j - 2]; *reg_packet_p++ = hex_buf[j - 1]; } free(hex_buf); } reg_packet_p = strndup(reg_packet, CEIL(reg_packet_size, 8) * 2); DEBUG("reg_packet: %s", reg_packet_p); free(reg_packet_p); gdb_put_packet(connection, reg_packet, CEIL(reg_packet_size, 8) * 2); free(reg_packet); } void gdb_set_registers_packet(connection_t *connection, target_t *target, char *packet, int packet_size) { int i; reg_t **reg_list; int reg_list_size; int retval; char *packet_p; DEBUG(""); /* skip command character */ packet++; packet_size--; if (packet_size % 2) { WARNING("GDB set_registers packet with uneven characters received"); return; } if ((retval = target->type->get_gdb_reg_list(target, ®_list, ®_list_size)) != ERROR_OK) { switch (retval) { case ERROR_TARGET_NOT_HALTED: ERROR("gdb requested registers, but we're not halted"); exit(-1); default: ERROR("BUG: unexpected error returned by get_gdb_reg_list()"); exit(-1); } } packet_p = packet; for (i = 0; i < reg_list_size; i++) { char_to_buf(packet, CEIL(reg_list[i]->size, 8) * 2, reg_list[i]->value, reg_list[i]->size); reg_list[i]->dirty = 1; } gdb_put_packet(connection, "OK", 2); } void gdb_get_register_packet(connection_t *connection, target_t *target, char *packet, int packet_size) { char *hex_buf; char *reg_packet; char *reg_packet_p; int reg_num = strtoul(packet + 1, NULL, 16); reg_t **reg_list; int reg_list_size; int retval; int i; DEBUG(""); if ((retval = target->type->get_gdb_reg_list(target, ®_list, ®_list_size)) != ERROR_OK) { switch (retval) { case ERROR_TARGET_NOT_HALTED: ERROR("gdb requested registers, but we're not halted"); exit(-1); default: ERROR("BUG: unexpected error returned by get_gdb_reg_list()"); exit(-1); } } if (reg_list_size <= reg_num) { ERROR("gdb requested a non-existing register"); exit(-1); } hex_buf = buf_to_char(reg_list[reg_num]->value, reg_list[reg_num]->size); reg_packet = reg_packet_p = malloc(CEIL(reg_list[reg_num]->size, 8) * 2); for (i = CEIL(reg_list[reg_num]->size, 8) * 2; i > 0; i -= 2) { *reg_packet_p++ = hex_buf[i - 2]; *reg_packet_p++ = hex_buf[i - 1]; } gdb_put_packet(connection, reg_packet, CEIL(reg_list[reg_num]->size, 8) * 2); free(reg_packet); free(hex_buf); } void gdb_set_register_packet(connection_t *connection, target_t *target, char *packet, int packet_size) { char *separator; int reg_num = strtoul(packet + 1, &separator, 16); reg_t **reg_list; int reg_list_size; int retval; DEBUG(""); if ((retval = target->type->get_gdb_reg_list(target, ®_list, ®_list_size)) != ERROR_OK) { switch (retval) { case ERROR_TARGET_NOT_HALTED: ERROR("gdb requested registers, but we're not halted"); exit(-1); default: ERROR("BUG: unexpected error returned by get_gdb_reg_list()"); exit(-1); } } if (reg_list_size < reg_num) { ERROR("gdb requested a non-existing register"); exit(-1); } if (*separator != '=') { ERROR("GDB set register packet, but no '=' following the register number"); exit(-1); } char_to_buf(separator + 1, CEIL(reg_list[reg_num]->size, 8) * 2, reg_list[reg_num]->value, reg_list[reg_num]->size); reg_list[reg_num]->dirty = 1; gdb_put_packet(connection, "OK", 2); } void gdb_read_memory_packet(connection_t *connection, target_t *target, char *packet, int packet_size) { char *separator; u32 addr = 0; u32 len = 0; u8 *buffer; char *hex_buffer; int i; /* skip command character */ packet++; addr = strtoul(packet, &separator, 16); if (*separator != ',') return; len = strtoul(separator+1, NULL, 16); buffer = malloc(len); DEBUG("addr: 0x%8.8x, len: 0x%8.8x", addr, len); switch (len) { case 4: if ((addr % 4) == 0) target->type->read_memory(target, addr, 4, 1, buffer); else target->type->read_memory(target, addr, 1, len, buffer); break; case 2: if ((addr % 2) == 0) target->type->read_memory(target, addr, 2, 1, buffer); else target->type->read_memory(target, addr, 1, len, buffer); break; default: if (((addr % 4) == 0) && ((len % 4) == 0)) target->type->read_memory(target, addr, 4, len / 4, buffer); else target->type->read_memory(target, addr, 1, len, buffer); } hex_buffer = malloc(len * 2 + 1); for (i=0; itype->write_memory(target, addr, 4, 1, buffer); else target->type->write_memory(target, addr, 1, len, buffer); break; case 2: if ((addr % 2) == 0) target->type->write_memory(target, addr, 2, 1, buffer); else target->type->write_memory(target, addr, 1, len, buffer); break; case 3: case 1: target->type->write_memory(target, addr, 1, len, buffer); break; /* handle bulk writes */ default: target_write_buffer(target, addr, len, buffer); break; } gdb_put_packet(connection, "OK", 2); free(buffer); } void gdb_write_memory_binary_packet(connection_t *connection, target_t *target, char *packet, int packet_size) { char *separator; u32 addr = 0; u32 len = 0; u8 *buffer; /* skip command character */ packet++; addr = strtoul(packet, &separator, 16); if (*separator != ',') return; len = strtoul(separator+1, &separator, 16); if (*(separator++) != ':') return; if( len ) { buffer = malloc(len); DEBUG("addr: 0x%8.8x, len: 0x%8.8x", addr, len); memcpy( buffer, separator, len ); switch (len) { case 4: if ((addr % 4) == 0) target->type->write_memory(target, addr, 4, 1, buffer); else target->type->write_memory(target, addr, 1, len, buffer); break; case 2: if ((addr % 2) == 0) target->type->write_memory(target, addr, 2, 1, buffer); else target->type->write_memory(target, addr, 1, len, buffer); break; case 3: case 1: target->type->write_memory(target, addr, 1, len, buffer); break; default: target_write_buffer(target, addr, len, buffer); break; } free(buffer); } gdb_put_packet(connection, "OK", 2); } void gdb_step_continue_packet(connection_t *connection, target_t *target, char *packet, int packet_size) { int current = 0; u32 address = 0x0; DEBUG(""); if (packet_size > 1) { u32 address = 0; packet[packet_size] = 0; address = strtoul(packet + 1, NULL, 16); } else { current = 1; } if (packet[0] == 'c') { DEBUG("continue"); target->type->resume(target, current, address, 0, 0); /* resume at current address, don't handle breakpoints, not debugging */ } else if (packet[0] == 's') { DEBUG("step"); target->type->step(target, current, address, 0); /* step at current or address, don't handle breakpoints */ } } void gdb_breakpoint_watchpoint_packet(connection_t *connection, target_t *target, char *packet, int packet_size) { int type; enum breakpoint_type bp_type; enum watchpoint_rw wp_type; u32 address; u32 size; char *separator; int retval; DEBUG(""); type = strtoul(packet + 1, &separator, 16); if (type == 0) /* memory breakpoint */ bp_type = BKPT_SOFT; else if (type == 1) /* hardware breakpoint */ bp_type = BKPT_HARD; else if (type == 2) /* write watchpoint */ wp_type = WPT_WRITE; else if (type == 3) /* read watchpoint */ wp_type = WPT_READ; else if (type == 4) /* access watchpoint */ wp_type = WPT_ACCESS; if (*separator != ',') return; address = strtoul(separator+1, &separator, 16); if (*separator != ',') return; size = strtoul(separator+1, &separator, 16); switch (type) { case 0: case 1: if (packet[0] == 'Z') { if ((retval = breakpoint_add(target, address, size, bp_type)) != ERROR_OK) { if (retval == ERROR_TARGET_RESOURCE_NOT_AVAILABLE) { gdb_put_packet(connection, "E00", 3); break; } } } else { breakpoint_remove(target, address); } gdb_put_packet(connection, "OK", 2); break; case 2: case 3: case 4: { if (packet[0] == 'Z') watchpoint_add(target, address, size, type-2, 0, 0xffffffffu); else watchpoint_remove(target, address); gdb_put_packet(connection, "OK", 2); break; } default: break; } } void gdb_query_packet(connection_t *connection, char *packet, int packet_size) { command_context_t *cmd_ctx = connection->cmd_ctx; gdb_service_t *gdb_service = connection->service->priv; target_t *target = gdb_service->target; if (strstr(packet, "qRcmd,")) { if (packet_size > 6) { char *cmd; int i; cmd = malloc((packet_size - 6)/2 + 1); for (i=0; i < (packet_size - 6)/2; i++) { u32 tmp; sscanf(packet + 6 + 2*i, "%2x", &tmp); cmd[i] = tmp; } cmd[(packet_size - 6)/2] = 0x0; command_run_line(cmd_ctx, cmd); free(cmd); } gdb_put_packet(connection, "OK", 2); return; } gdb_put_packet(connection, "", 0); } int gdb_input(connection_t *connection) { gdb_service_t *gdb_service = connection->service->priv; target_t *target = gdb_service->target; char packet[GDB_BUFFER_SIZE]; int packet_size; int retval; gdb_connection_t *gdb_con = connection->priv; /* drain input buffer */ do { packet_size = GDB_BUFFER_SIZE-1; if ((retval = gdb_get_packet(connection, packet, &packet_size)) != ERROR_OK) { switch (retval) { case ERROR_GDB_BUFFER_TOO_SMALL: ERROR("BUG: buffer supplied for gdb packet was too small"); exit(-1); case ERROR_SERVER_REMOTE_CLOSED: return ERROR_SERVER_REMOTE_CLOSED; default: ERROR("unexpected error"); exit(-1); } } /* terminate with zero */ packet[packet_size] = 0; DEBUG("recevied packet: '%s'", packet); if (packet_size > 0) { switch (packet[0]) { case 'H': /* Hct... -- set thread * we don't have threads, send empty reply */ gdb_put_packet(connection, NULL, 0); break; case 'q': gdb_query_packet(connection, packet, packet_size); break; case 'g': gdb_get_registers_packet(connection, target, packet, packet_size); break; case 'G': gdb_set_registers_packet(connection, target, packet, packet_size); break; case 'p': gdb_get_register_packet(connection, target, packet, packet_size); break; case 'P': gdb_set_register_packet(connection, target, packet, packet_size); break; case 'm': gdb_read_memory_packet(connection, target, packet, packet_size); break; case 'M': gdb_write_memory_packet(connection, target, packet, packet_size); break; case 'z': case 'Z': gdb_breakpoint_watchpoint_packet(connection, target, packet, packet_size); break; case '?': gdb_last_signal_packet(connection, target, packet, packet_size); break; case 'c': case 's': gdb_step_continue_packet(connection, target, packet, packet_size); break; case 'D': target->type->resume(target, 1, 0, 1, 0); gdb_put_packet(connection, "OK", 2); break; case 'X': gdb_write_memory_binary_packet(connection, target, packet, packet_size); break; case 'k': gdb_put_packet(connection, "OK", 2); return ERROR_SERVER_REMOTE_CLOSED; default: /* ignore unkown packets */ DEBUG("ignoring 0x%2.2x packet", packet[0]); gdb_put_packet(connection, NULL, 0); break; } } if (gdb_con->ctrl_c) { if (target->state == TARGET_RUNNING) { target->type->halt(target); gdb_con->ctrl_c = 0; } } } while (gdb_con->buf_cnt > 0); return ERROR_OK; } int gdb_init() { gdb_service_t *gdb_service; target_t *target = targets; int i = 0; if (!target) { WARNING("no gdb ports allocated as no target has been specified"); return ERROR_OK; } if (gdb_port == 0) { WARNING("no gdb port specified, using default port 3333"); gdb_port = 3333; } while (target) { char service_name[8]; snprintf(service_name, 8, "gdb-%2.2i", i); gdb_service = malloc(sizeof(gdb_service_t)); gdb_service->target = target; add_service("gdb", CONNECTION_GDB, gdb_port + i, 1, gdb_new_connection, gdb_input, gdb_connection_closed, gdb_service); DEBUG("gdb service for target %s at port %i", target->type->name, gdb_port + i); target = target->next; } return ERROR_OK; } /* daemon configuration command gdb_port */ int handle_gdb_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc) { if (argc == 0) return ERROR_OK; /* only if the port wasn't overwritten by cmdline */ if (gdb_port == 0) gdb_port = strtoul(args[0], NULL, 0); return ERROR_OK; } int gdb_register_commands(command_context_t *command_context) { register_command(command_context, NULL, "gdb_port", handle_gdb_port_command, COMMAND_CONFIG, ""); return ERROR_OK; }