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#include "FTPd.h" void do_child(); /* 输出到客户端 */ void outs(char *fmt, ...)
{
static char tmp[80];
va_list ap; va_start(ap, fmt);
sprintf(tmp, "%s\r\n", fmt);
vsprintf(genbuf, tmp, ap);
send(connfd, genbuf, strlen(genbuf), 0);
va_end(ap);
};/* 将buf以空格做分隔符分解成两个字符串 */ void explode(char *buf, char **cmd, char **param)
{
char *p;
while ((p = &buf[strlen(buf)-1]) && (*p == '\r' || *p == '\n')) *p = 0;
p = strchr(buf, ' ');
*cmd = buf;
if (!p) *param = NULL;
else {
*p = 0;
*param = p+1;
};
};int MakePath(char *new_path, char* path, char* filename)
{
return sprintf(new_path, "%s%s/%s", basedir, path, filename);
};
void Error(char *param)
{
switch (errno) {
case ENOTEMPTY:
ERRS("Directory not empty");
break;
case ENOSPC:
ERRS("disk full");
break;
case EEXIST:
ERRS("File exists");
break;
case ENAMETOOLONG:
ERRS("path is too long");
break;
case ENOENT:
ERRS("No such file or directory");
break;
case ENOTDIR:
ERRS("Not a directory");
break;
case EISDIR:
ERRS("Is a directory");
default:
ERRS("Permission denied");
};
}int Check(char *cmd, char *param, int check)
{
if (check & CHECK_LOGIN && !user_valid) {
outs("530 Please login with USER and PASS");
return 0;
};
if (check & CHECK_NOLOGIN && user_valid) {
outs("503 You are already logged in!");
return 0;
};
if (check & NEED_PARAM) {
if (!param) outs("501 Invalid number of arguments, check more arguments.");
return (param != NULL);
};
if (check & NO_PARAM) {
if (param) outs("501 Invalid number of arguments.");
return (param == NULL);
};return 1; }; void DataConnection(int mode, int transfer_type, char *filename)
{
int datafd;
struct sockaddr_in sa;
socklen_t len = sizeof(sa);
char buf[BUFSIZE], *p;
int readlen;
FILE *tmp; if (data_pid != 0 && kill(data_pid, 0) == 0) {
outs("425 Try later, data connection in use.");
return;
};
if ((data_pid = fork()) == 0) {
if (pasv_mode) {
if ((datafd = accept(pasvfd, (struct sockaddr *)&sa, &len)) == -1) {
close(pasvfd);
exit(-1);
};
} else {
memset(&sa, 0, len);
sa.sin_family = AF_INET;
sa.sin_addr.s_addr = remote_port.host;
sa.sin_port = remote_port.port;
if ((datafd = socket(AF_INET, SOCK_STREAM, 0)) == -1 || connect(datafd, (struct sockaddr *)&sa, len) == -1) {
exit(-1);
};
};
outs("150 Opening %s mode data connection for %s.", (transfer_type == 'i')?"BINARY":"ASCII", filename);
if (mode) {
/* write */
if (transfer_type == 'i') {
while ((readlen = fread(buf, 1, BUFSIZE, data_file)) >0 ) {
send(datafd, buf, readlen, 0);
};
} else {
while ((fgets(buf, BUFSIZE, data_file) != NULL)) {
while ((p = &buf[strlen(buf)-1]) && (*p == '\r' || *p == '\n')) *p = 0;
strcat(buf, "\r\n");
send(datafd, buf, strlen(buf), 0);
};
};
} else {
/* read */
if (transfer_type == 'i') {
while ((readlen = recv(datafd, buf, BUFSIZE, 0)) >0 ) {
if (fwrite(buf, 1, readlen, data_file) == -1) break;
};
} else {
tmp = fdopen(datafd, "r");
while ((fgets(buf, BUFSIZE, tmp) != NULL)) {
while ((p = &buf[strlen(buf)-1]) && (*p == '\r' || *p == '\n')) *p = 0;
strcat(buf, "\n");
if (fwrite(buf, 1, strlen(buf), data_file) == -1) break;
};
};
};
close(datafd); exit(0);
};
};
void Help(char *param)
{
if (!param) {
outs("214 The following commands are recognized (* =>'s unimplemented).");
outs("214 USER PASS ACCT* CWD XCWD CDUP XCUP SMNT* ");
outs("214 QUIT REIN* PORT PASV TYPE STRU* MODE* RETR ");
outs("214 STOR STOU* APPE ALLO* REST RNFR RNTO ABOR ");
outs("214 DELE MDTM RMD XRMD MKD XMKD PWD XPWD ");
outs("214 SIZE LIST NLST SITE SYST STAT HELP NOOP ");
outs("214 Direct comments to nolove@263.net");
} else {
outs("214 Sorry, I haven't write the topic help.");
};
};void User(char *param)
{
if (user_valid) {
outs("503 You are already logged in!");
return;
};
if (!param) {
outs("500 \'USER\': command requires a parameter.");
return;
};
strncpy(username, param, 100);
if (strcasecmp(username, "anonymous") == 0) {
anonymous_login = 1;
strncpy(username, "ftp", 100);
outs("331 Anonymous login ok, send your complete e-mail address as password.");
} else outs("331 Password required for %s", username);
input_user = 1; }; void Pass(char *param)
{
struct passwd *pw;
struct spwd *spw;
char *passwd, salt[13];
if (!input_user) {
outs("503 Login with USER first.");
return;
};
/* judge and chdir to its home directory */
if (!anonymous_login) {
if (system_uid != 0) {
outs("530 Login incorrect.");
input_user = 0;
return;
};
if ((pw = getpwnam(username)) == NULL) {
outs("530 Login incorrect.");
input_user = 0;
return;
};
passwd = pw->pw_passwd;
if (passwd == NULL || strcmp(passwd, "x") == 0) {
spw = getspnam(username);
if (spw == NULL || (passwd = spw->sp_pwdp) == NULL) {
outs("530 Login incorrect.");
input_user = 0;
return;
};
}; strncpy(salt, passwd, 12);
if (strcmp(passwd, crypt(param, salt)) != 0) {
outs("530 Login incorrect.");
input_user = 0;
return;
};
strcpy(path, "");
setuid(pw->pw_uid);
if (pw->pw_dir) strncpy(path, pw->pw_dir, PATH_MAX);
else strcpy(path, "/"); outs("230 User %s logged in.", username);
chdir(path);
getcwd(path, PATH_MAX);
user_valid = 1;
} else {
if ((pw = getpwuid(system_uid)) == NULL) {
outs("530 Login incorrect.");
input_user = 0;
return;
}; if (pw->pw_dir) strncpy(basedir, pw->pw_dir, PATH_MAX);
else strcpy(basedir, "");
strcpy(path, "/"); chdir(basedir);
getcwd(basedir, PATH_MAX);
user_valid = 1;
outs("230 Anonymous access granted, restrictions apply.");
}; user_valid = 1;
outs("230 Anonymous access granted, restrictions apply.");
};void Pwd(char *param)
{
outs("257 \"%s\" is current directory.", path);
};void Cwd(char *param)
{
char tmp[PATH_MAX];
if (param[0] == '/') MakePath(tmp, "", param); else MakePath(tmp, path, param);
if (chdir(tmp) == -1) {
Error(param);
} else {
if (getcwd(tmp, PATH_MAX) == NULL) ERRS("Permission denied");
else {
if (anonymous_login) {
if (strncmp(basedir, tmp, strlen(basedir)) != 0) {
chdir(basedir);
strcpy(path, "/");
} else {
strncpy(path, &tmp[strlen(basedir)], PATH_MAX);
strcat(path, "/");
};
} else strcpy(path, tmp);
outs("250 CWD command successful.");
};
};
};void Cdup(char *param)
{
Cwd("..");
};void Mkd(char *param)
{
if (mkdir(param, 0755) == -1) {
Error(param);
} else {
outs("257 \"%s/%s\" - Directory successfully created.", path, param);
};
};void Rmd(char *param)
{
if (rmdir(param) == -1) {
Error(param);
} else {
outs("250 RMD command successful.");
};
};void Type(char *param)
{
if (strcasecmp(param, "i") == 0) {
outs("200 Type set to I");
transfer_type = 'i';
return;
};
if (strcasecmp(param, "a") == 0) {
outs("200 Type set to A");
transfer_type = 'a';
return;
};
outs("500 \'TYPE %s\' not understood.", param);
};void Size(char *param)
{
struct stat s;
if (stat(param, &s) == -1) {
Error(param);
} else {
if (S_ISREG(s.st_mode)) outs("213 %d", s.st_size);
else outs("550 %s: not a regular file.", param);
};
};void Stat(char *param)
{
FILE *f;
static char tmp[PATH_MAX], tmp2[PATH_MAX];
static char statbuf[BUFSIZE];
outs("211-status of \"%s\":", param);
if (strchr(param, ' ') != NULL) sprintf(tmp2, "\"%s\"", param);
else sprintf(tmp2, "%s", param);
sprintf(tmp, "/bin/ls -l --color=never %s", tmp2);
if ((f = popen(tmp, "r")) != NULL) {
while (fgets(statbuf, BUFSIZE, f) != NULL) {
if (statbuf[0] == 't') continue;
send(connfd, statbuf, strlen(statbuf), 0);
};
pclose(f);
};
outs("211 End of Status");
};void Dele(char *param)
{
if (unlink(param) == -1) {
Error(param);
} else {
FIXME: outs("250 DELE command successful.", param);
};
};
void Quit(char *param)
{
outs("221 Goodbye");
fclose(file);
exit(0);
};void Noop(char *param)
{
outs("200 NOOP command successful");
};void DoList(char *param, char *cmd)
{
char tmp[PATH_MAX], tmp2[PATH_MAX];
char *mode = "r";
MakePath(tmp, path, param); if (param) {
if (strchr(param, ' ') != NULL) sprintf(tmp2, "\"%s\"", param);
else sprintf(tmp2, "%s", param);
} else strcpy(tmp2, "");
sprintf(tmp, "/bin/ls %s --color=never %s", cmd, tmp2);
if ((data_file = popen(tmp, mode)) == NULL) {
Error("LIST");
return;
};
DataConnection(1, 'a', "/bin/ls"); }; void List(char *param)
{
DoList(param, "-l");
};void Nlst(char *param)
{
DoList(param, "-1");
};void PreConnection(char *param, char open_mode, int data_mode)
{
char tmp[PATH_MAX];
char mode[3];
struct stat s;
MakePath(tmp, path, param);
mode[0] = open_mode;
if (transfer_type == 'i') mode[1] = 'b'; else mode[1] = 't';
mode[2] = 0;
if (data_mode && stat(tmp, &s) == -1)
{
Error(param);
return;
}; if ((data_file = fopen(tmp, mode)) == NULL) {
Error(param);
return;
};
if (open_mode != 'a') fseek(data_file, file_rest, SEEK_SET);
if (data_mode) {
sprintf(tmp, "%s (%d bytes)", param, s.st_size - file_rest);
} else {
strcpy(tmp, param);
};
DataConnection(data_mode, transfer_type, tmp); }; void Retr(char *param)
{
PreConnection(param, 'r', 1);
};void Stor(char *param)
{
PreConnection(param, 'w', 0);
};void Appe(char *param)
{
PreConnection(param, 'a', 0);
};void Abor(char *param)
{
if (data_pid != 0) {
kill(data_pid, SIGTERM);
};
outs("226 ABOR command successful.");
};void Mdtm(char *param)
{
struct stat s;
struct tm *tms;
if (stat(param, &s) == -1) {
Error(param);
} else {
tms = localtime((const time_t *)&s.st_mtime);
outs("213 %4d%2d%2d%2d%2d%2d", tms->tm_year, tms->tm_mon, tms->tm_mday, tms->tm_hour, tms->tm_min, tms->tm_sec);
};
};void Syst(char *param)
{
outs("215 UNIX Type: L8");
};void Rest(char *param)
{
int r;
r = atoi(param);
if (r < 0 || (r == 0 && param[0] != '0')) {
outs("501 REST requires a value greater than or equal to 0.");
return;
};
file_rest = r;
outs("350 Restarting at %u. Send STORE or RETRIEVE to initiate transfer.", file_rest);
};void Rnfr(char *param)
{
char tmp[PATH_MAX];
struct stat s;
MakePath(tmp, path, param);
if (stat(tmp, &s) == -1) {
Error(tmp);
} else {
outs("350 File or directory exists, ready for destination name.");
strncpy(rename_file, param, PATH_MAX);
};
};void Rnto(char *param)
{
char tmp[PATH_MAX];
if (strcmp(rename_file, "") == 0) {
outs("503 Bad sequence of commands.");
return;
}; MakePath(tmp, path, param);
if (rename(rename_file, tmp) == -1) {
Error(tmp);
} else {
outs("250 RNTO command successful.");
strcpy(rename_file, "");
};
};
void Site(char *param)
{
int i, mode;
static char buf[BUFSIZE] = "250 ";
FILE *f;
char *p1, *p2, *p3, *p4, tmp[PATH_MAX], tmp2[PATH_MAX];
explode(param, &p1, &p2); if (p1 == NULL || p2 == NULL || strncasecmp(p1, "CHMOD", 5) != 0) {
outs("501 SITE option not supported.");
return;
};
explode(p2, &p3, &p4);
if (p3 == NULL || p4 == NULL) {
outs("501 SITE option not supported.");
return;
}; mode = strtol(p3, (char **)NULL, 8);
if (chmod(p4, mode) == -1) {
outs("501 SITE option not supported.");
} else {
outs("250 SITE command successful.");
};
};void Port(char *param)
{
int i;
struct _port tmp;
unsigned char r, *ptr = (unsigned char *)&tmp;
char *p, *ori = param;
for (i=0;i<6;i++) {
r = atoi(ori);
if (r == 0 && *ori != '0') {
outs("501 Syntax error in parameters or arguments.");
return;
};
ptr[i] = r;
p = strchr(ori, ',');
if (p == NULL) {
if (i != 5) {
outs("501 Syntax error in parameters or arguments.");
return;
};
} else {
*p = 0;
ori = p+1;
};
};
memcpy(&remote_port, &tmp, sizeof(remote_port));
pasv_mode = 0;
outs("200 PORT Command successful.");
};void Pasv(char *param)
{
int port = port_base;
struct sockaddr_in sa;
char tmp[30], t2[10];
int len, i;
len = 1;
close(pasvfd); if ((pasvfd = socket(AF_INET, SOCK_STREAM, 0)) == -1 || setsockopt(pasvfd, SOL_SOCKET, SO_REUSEADDR, (const char *)&len, sizeof(int)) == -1)
{
outs("550 PASV command failed.");
return;
}; memset(&sa, 0, sizeof(sa));
sa.sin_family = AF_INET;
sa.sin_addr.s_addr = htonl(INADDR_ANY); do {
port++;
if (port == 65535) {
outs("550 Can\'t bind any port.");
return;
};
sa.sin_port = htons(port);
} while (bind(pasvfd, (struct sockaddr *)&sa, sizeof(sa)) == -1 || listen(pasvfd, 1) == -1); local_port.port = htons(port);
memset(tmp, 0, 18);
for (i=0;i<6;i++) {
sprintf(t2, "%u", ((unsigned char *)&local_port)[i]);
strcat(tmp, t2);
if (i!=5) strcat(tmp, ",");
};
pasv_mode = 1;
outs("227 Entering Passive Mode (%s)", tmp);
};
struct _cmd_list cmd_list[] = {
{"USER", User, CHECK_NOLOGIN | NEED_PARAM },
{"PASS", Pass, CHECK_NOLOGIN },
{"ACCT"},
{"CWD", Cwd, CHECK_LOGIN | NEED_PARAM },
{"XCWD", Cwd, CHECK_LOGIN | NEED_PARAM },
{"CDUP", Cdup, CHECK_LOGIN | NO_PARAM },
{"XCUP", Cdup, CHECK_LOGIN | NO_PARAM },
{"SMNT"},
{"QUIT", Quit, NO_CHECK },
{"REIN"},
{"PORT", Port, CHECK_LOGIN | NEED_PARAM },
{"PASV", Pasv, CHECK_LOGIN | NO_PARAM },
{"TYPE", Type, CHECK_LOGIN | NEED_PARAM },
{"STRU"},
{"MODE"},
{"RETR", Retr, CHECK_LOGIN | NEED_PARAM },
{"STOR", Stor, CHECK_LOGIN | NEED_PARAM },
{"STOU"},
{"APPE", Appe, CHECK_LOGIN | NEED_PARAM },
{"ALLO"},
{"REST", Rest, CHECK_LOGIN | NEED_PARAM },
{"RNFR", Rnfr, CHECK_LOGIN | NEED_PARAM },
{"RNTO", Rnto, CHECK_LOGIN | NEED_PARAM },
{"ABOR", Abor, CHECK_LOGIN | NO_PARAM },
{"DELE", Dele, CHECK_LOGIN | NEED_PARAM },
{"MDTM", Mdtm, CHECK_LOGIN | NEED_PARAM },
{"RMD", Rmd, CHECK_LOGIN | NEED_PARAM },
{"XRMD", Rmd, CHECK_LOGIN | NEED_PARAM },
{"MKD", Mkd, CHECK_LOGIN | NEED_PARAM },
{"XMKD", Mkd, CHECK_LOGIN | NEED_PARAM },
{"PWD", Pwd, CHECK_LOGIN | NO_PARAM },
{"XPWD", Pwd, CHECK_LOGIN | NO_PARAM },
{"SIZE", Size, CHECK_LOGIN | NEED_PARAM },
{"LIST", List, CHECK_LOGIN },
{"NLST", List, CHECK_LOGIN },
{"SITE", Site, CHECK_LOGIN | NEED_PARAM },
{"SYST", Syst, CHECK_LOGIN },
{"STAT", Stat, CHECK_LOGIN | NEED_PARAM },
{"HELP", Help, NO_CHECK },
{"NOOP", Noop, NO_CHECK },
{""}
}; void do_alarm()
{
outs("421 No Transfer Timeout (%d seconds): closing control connection", timeout);
fclose(file);
close(connfd);
exit(0);
};void do_child()
{
int pid, ret;
while ((pid = waitpid(-1, &ret, WNOHANG|WUNTRACED)) > 0) {
if (pid == data_pid) {
if (WIFEXITED(ret) && WEXITSTATUS(ret) == 0) outs("226 Transfer complete.");
else if (WIFSIGNALED(ret) && WTERMSIG(ret) == SIGTERM) outs("425 Transfer aborted.");
else outs("425 Transfer error.");
fclose(data_file);
if (pasv_mode) close(pasvfd);
pasv_mode = 0;
transfer = 0;
data_pid = 0;
file_rest = 0;
};
};
};
void do_term()
{
outs("425 Transfer aborted.");
exit(0);
};int init()
{
int n, i;
struct sockaddr_in sa;
struct hostent *host;
struct in_addr ia;
/* register the signal handler */
signal(SIGCHLD, do_child);
signal(SIGTERM, do_term);
/* init network */
memset(&sa, 0, sizeof(sa));
sa.sin_family = AF_INET;
sa.sin_addr.s_addr = htonl(INADDR_ANY);
sa.sin_port = htons(ftp_port);
if (gethostname(hostname, BUFSIZE) == -1) strcpy(hostname, "");
i = 1;
if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) == -1 || setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, (const char *)&i, sizeof(int)) == -1)
{
perror("Pacific FTP:");
return -1;
};
if (bind(listenfd, (struct sockaddr *)&sa, sizeof(sa)) == -1) {
fprintf(stderr, "Pacific FTP: Can not bind port %d\n", ftp_port);
return -1;
};
if (listen(listenfd, max_conn) == -1) {
perror("Pacific FTP:");
return -1;
}; /* set the program a daemon */
if(fork()) exit(0); for (n = 0; n<3; n++) close(n);
open("/dev/null", O_RDONLY);
dup2(0,1);
dup2(0,2);
if((n=open("/dev/tty",O_RDWR)) > 0) {
ioctl(n, TIOCNOTTY, 0) ;
close(n);
}
setsid();
if(fork()) exit(0); /* get the uid */
system_uid = getuid();
}int main(int argc, char **argv)
{
struct sockaddr_in sa;
int len, cur;
int okay=1, i;
char *cmd, *param; /* get the param */
for (i=1; i<argc; i++) {
if (argv[i][0] != '-' || argv[i][2] != ':') okay = 0; switch (argv[i][1]) {
case 'p':
ftp_port = atoi(&argv[i][3]);
if (ftp_port == 0) okay = 0;
break;
case 'm':
max_conn = atoi(&argv[i][3]);
if (max_conn == 0) okay = 0;
break;
case 't':
timeout = atoi(&argv[i][3]);
if (timeout == 0) okay = 0;
break;
default:
okay = 0;
};
if (!okay) break;
};
if (!okay) {
printf("Usage: %s [-p:port] [-m:maxconn] [-t:timeout]\n\tport: default is 21.\n\tmaxconn: the max client num connected.\n", argv[0]);
return -1;
}; if (init() == -1) return -1;
/* main loop */
while (1)
{
len = sizeof(sa);
connfd = accept(listenfd, (struct sockaddr *)&sa, &len);
if (connfd == -1) continue;
if (fork() == 0)
{
len = sizeof(sa);
getsockname(connfd, (struct sockaddr *)&sa, &len);
local_port.host = sa.sin_addr.s_addr; file = fdopen(connfd, "rt+");
setbuf(file, (char *)0); getcwd(path, PATH_MAX);
outs("220 PacificFTP ready, hostname: %s", hostname);
signal(SIGALRM, do_alarm);
alarm(timeout); /* child process's main loop */
while (fgets(inbuf, BUFSIZE, file) != NULL)
{
explode(inbuf, &cmd, ¶m);
if (strcmp(cmd, "") == 0) continue; /* Make cmd UPPERCASE */
for (i=0;i<strlen(cmd);i++) cmd[i]=toupper(cmd[i]); cur = 0;
okay = 0;
while (strcmp(cmd_list[cur].cmd, "") != 0)
{
if (strcmp(cmd_list[cur].cmd, cmd) == 0) {
if (cmd_list[cur].func == NULL) outs("502 %s command unimplemented.", cmd);
else
if ((cmd_list[cur].check & NO_CHECK) || Check(cmd, param, cmd_list[cur].check))
(*cmd_list[cur].func)(param);
okay = 1;
break;
};
cur++;
};
if (!okay) outs("500 %s not understood", cmd);
};
fclose(file);
exit(0);
};
close(connfd);
};
} |