| 0,0 → 1,316 |
|---|
| /****************************************************************** |
| * |
| * Daemon which waiting on specified TCP port for special string |
| * and reboot the computer. |
| * |
| * Command line: rebootdaemon [--port PORT] [--config CONFIG_FILE] |
| * Defaults are port 19 and config /etc/rebootdaemon.conf. |
| * |
| * Config file looks like: |
| * -------------------------- |
| * port=19 |
| * password="some password" |
| * -------------------------- |
| * |
| * Usage example (from any other host): |
| * echo -n "some password" | nc host_to_rebot 19 |
| * |
| * Copyleft 2005 Anatoli Klassen |
| * |
| ******************************************************************/ |
| |
| #include <stdlib.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <stdarg.h> |
| #include <errno.h> |
| #include <signal.h> |
| #include <unistd.h> |
| #include <netdb.h> |
| #include <syslog.h> |
| #include <sys/types.h> |
| #include <sys/socket.h> |
| #include <sys/wait.h> |
| #include <sys/reboot.h> |
| #include <netinet/in.h> |
| #include <arpa/inet.h> |
| |
| #define PORT 19 |
| #define CFG_FILE "/etc/rebootdaemon.conf" |
| #define CMDSIZE 4096 |
| #define BUFSIZE 4096 |
| #define MAX_CONFIG_LINE 4096 |
| #define PORT_MIN 1 |
| #define PORT_MAX 65535 |
| |
| #define PARAM_PORT_1 "-p" |
| #define PARAM_PORT_2 "--port" |
| #define PARAM_CONFIG_1 "-c" |
| #define PARAM_CONFIG_2 "--config" |
| #define CONFIG_PORT "port" |
| #define CONFIG_PASSWORD "password" |
| |
| struct config { |
| int port; |
| char password[MAX_CONFIG_LINE]; |
| }; |
| |
| static struct config cfg; |
| |
| static int parse_cmd_line(int argc, char* argv[], long *port, char *config_name); |
| static int parse_config_file(char *config_name, long *port, char *password); |
| |
| static int min(int a, int b) |
| { |
| return (a < b) ? a : b; |
| } |
| |
| static int establish(unsigned short portnum) |
| { |
| int s; |
| struct sockaddr_in sa; |
| |
| memset(&sa, 0, sizeof(struct sockaddr_in)); |
| |
| sa.sin_family = AF_INET; |
| sa.sin_port = htons(portnum); |
| sa.sin_addr.s_addr = INADDR_ANY; |
| |
| if((s = socket(AF_INET, SOCK_STREAM, 0)) < 0) |
| return -1; |
| |
| if(bind(s, (struct sockaddr *)&sa, sizeof(struct sockaddr_in)) < 0) { |
| close(s); |
| return -1; |
| } |
| |
| listen(s, 1); |
| |
| return s; |
| } |
| |
| static int print_cmd_error(char *msg, char *value) |
| { |
| fprintf(stderr, "%s", msg); |
| if(value) fprintf(stderr, " - %s\n", value); |
| fprintf(stderr, "\n"); |
| |
| return 0; |
| } |
| |
| static int print_config_error(char *config_name, int line, char *msg, char *value) |
| { |
| fprintf(stderr, "Error in %s, line %d: %s", config_name, line, msg); |
| if(value) fprintf(stderr, " - %s", value); |
| fprintf(stderr, "\n"); |
| |
| return 0; |
| } |
| |
| static int read_config(int argc, char* argv[]) |
| { |
| long cmd_port; |
| long file_port; |
| char cmd_config[MAX_CONFIG_LINE]; |
| |
| if(!parse_cmd_line(argc, argv, &cmd_port, cmd_config)) return 0; |
| |
| if(!parse_config_file(cmd_config[0] != '\0' ? cmd_config : CFG_FILE, &file_port, cfg.password)) return 0; |
| |
| if(cfg.password[0] == '\0') { |
| fprintf(stderr, "Password is not set\n"); |
| return 0; |
| } |
| |
| if(cmd_port > 0) |
| cfg.port = (int)cmd_port; |
| else if(file_port > 0) |
| cfg.port = (int)file_port; |
| else |
| cfg.port = PORT; |
| |
| return 1; |
| } |
| |
| static int parse_cmd_line(int argc, char* argv[], long *port, char *config_name) |
| { |
| char *end; |
| int i; |
| |
| *port = 0; |
| config_name[0] = '\0'; |
| |
| for(i = 1; i < argc; i++) { |
| if(0 == strcmp(argv[i], PARAM_PORT_1) || 0 == strcmp(argv[i], PARAM_PORT_2)) { |
| if(*port > 0) |
| return print_cmd_error("Port is already set", NULL); |
| |
| if(++i < argc) { |
| *port = strtol(argv[i], &end, 10); |
| if(*end != '\0' || *port < PORT_MIN || *port > PORT_MAX) |
| return print_cmd_error("Port number must be integer between 1 and 65535", NULL); |
| } |
| else { |
| return print_cmd_error("Port number expected", NULL); |
| } |
| } |
| else if(0 == strcmp(argv[i], PARAM_CONFIG_1) || 0 == strcmp(argv[i], PARAM_CONFIG_2)) { |
| if(config_name[0] != '\0') |
| return print_cmd_error("Config file is already set", NULL); |
| |
| if(++i < argc) { |
| strncpy(config_name, argv[i], MAX_CONFIG_LINE); |
| if(config_name[MAX_CONFIG_LINE - 1] != '\0') |
| return print_cmd_error("Config file name is too long", NULL); |
| } |
| else { |
| return print_cmd_error("Config file expected", NULL); |
| } |
| } |
| else { |
| return print_cmd_error("Unknown parameter", argv[i]); |
| } |
| } |
| |
| return 1; |
| } |
| |
| |
| static int parse_config_file(char *config_name, long *port, char *password) |
| { |
| FILE *config_file; |
| char buf[MAX_CONFIG_LINE]; |
| char *line; |
| char *subline; |
| char *cur; |
| int count; |
| |
| config_file = fopen(config_name, "r"); |
| if(!config_file) { |
| fprintf(stderr, "Can not open config file %s: %s\n", config_name, strerror(errno)); |
| return 0; |
| } |
| |
| count = 0; |
| while(fgets(buf, sizeof(buf), config_file)) { |
| count++; |
| line = buf; |
| |
| /* skip end spaces */ |
| int len = strlen(line); |
| while(len && isspace(line[len-1])) --len; |
| if(!len) continue; |
| line[len] = '\0'; |
| |
| /* skip begin spaces */ |
| while(line[0] != '\0' && isspace(line[0])) line++; |
| |
| if('#' == line[0]) { /* skip comment lines */ |
| continue; |
| } |
| else if(strncmp(line, CONFIG_PORT, min(sizeof(CONFIG_PORT) - 1, len)) == 0) { |
| subline = line + sizeof(CONFIG_PORT) - 1; |
| while(subline[0] != '\0' && isspace(subline[0])) subline++; |
| if('=' != subline[0]) |
| return print_config_error(config_name, count, "Equal sign expected", NULL); |
| subline++; |
| *port = strtol(subline, &subline, 10); |
| if(*port < PORT_MIN || *port > PORT_MAX) |
| return print_config_error(config_name, count, |
| "Port number must be integer between 1 and 65535", NULL); |
| while(subline[0] != '\0' && isspace(subline[0])) subline++; |
| if('\0' != subline[0] && '#' != subline[0]) |
| return print_config_error(config_name, count, "End of line expected", NULL); |
| } |
| else if(strncmp(line, CONFIG_PASSWORD, min(sizeof(CONFIG_PASSWORD) - 1, len)) == 0) { |
| subline = line + sizeof(CONFIG_PASSWORD) - 1; |
| while(subline[0] != '\0' && isspace(subline[0])) subline++; |
| if('=' != subline[0]) |
| return print_config_error(config_name, count, "Equal sign expected", NULL); |
| subline++; |
| while(subline[0] != '\0' && isspace(subline[0])) subline++; |
| if('"' != subline[0]) |
| return print_config_error(config_name, count, "Open quot expected", NULL); |
| subline++; |
| |
| cur = password; |
| while(subline[0] != '\0' && subline[0] != '"') { |
| cur[0] = subline[0]; |
| cur++; |
| subline++; |
| } |
| |
| cur[0] = '\0'; |
| if('"' != subline[0]) |
| return print_config_error(config_name, count, "Close quot expected", NULL); |
| subline++; |
| while(subline[0] != '\0' && isspace(subline[0])) subline++; |
| if('\0' != subline[0] && '#' != subline[0]) |
| return print_config_error(config_name, count, "End of line expected", NULL); |
| } |
| else { |
| return print_config_error(config_name, count, "Unknown config parameter", line); |
| } |
| } |
| |
| if(fclose(config_file) != 0) { |
| fprintf(stderr, "Can not close config file %s: %s\n", config_name, strerror(errno)); |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| int main(int argc, char* argv[]) |
| { |
| int s, t; |
| char cmd[CMDSIZE]; |
| char buf[BUFSIZE]; |
| char* msg; |
| int br; |
| struct sockaddr_in sa; |
| socklen_t sa_len; |
| |
| if(!read_config(argc, argv)) return 1; |
| |
| if((s = establish(cfg.port)) < 0) { |
| fprintf(stderr, "Cannot listen to port %i\n", cfg.port); |
| return 1; |
| } |
| |
| for(;;) { |
| sa_len = sizeof(sa); |
| if((t = accept(s, (struct sockaddr *)&sa, &sa_len)) < 0) { |
| if(errno == EINTR) /* EINTR might happen on accept(), */ |
| continue; /* try again */ |
| |
| msg = strerror(errno); |
| syslog(LOG_ERR, "cannot get connection, %s", msg); |
| continue; |
| } |
| |
| msg = inet_ntoa(sa.sin_addr); |
| syslog(LOG_INFO, "connect from %s", msg); |
| |
| cmd[0] = '\0'; |
| while((br = recv(t, buf, BUFSIZE, 0)) > 0) { |
| strncat(cmd, buf, min(br, sizeof(cmd) - strlen(cmd) - 1)); |
| } |
| sleep(1); |
| close(t); |
| |
| syslog(LOG_INFO, "got command [%s]", cmd); |
| |
| if(0 == strncmp(cmd, cfg.password, sizeof(cmd))) { |
| syslog(LOG_EMERG, "REBOOT"); |
| sleep(5); |
| if(reboot(RB_AUTOBOOT) < 0) { |
| msg = strerror(errno); |
| syslog(LOG_ERR, "cannot reboot, %s", msg); |
| } |
| } |
| } |
| |
| return 0; |
| } |
| |