diff options
Diffstat (limited to 'usr.sbin/inetd/builtins.c')
| -rw-r--r-- | usr.sbin/inetd/builtins.c | 814 |
1 files changed, 0 insertions, 814 deletions
diff --git a/usr.sbin/inetd/builtins.c b/usr.sbin/inetd/builtins.c deleted file mode 100644 index d75a5e4..0000000 --- a/usr.sbin/inetd/builtins.c +++ /dev/null @@ -1,814 +0,0 @@ -/*- - * Copyright (c) 1983, 1991, 1993, 1994 - * The Regents of the University of California. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#include <sys/cdefs.h> -__FBSDID("$FreeBSD$"); - -#include <sys/filio.h> -#include <sys/ioccom.h> -#include <sys/param.h> -#include <sys/stat.h> -#include <sys/socket.h> -#include <sys/sysctl.h> -#include <sys/ucred.h> -#include <sys/uio.h> -#include <sys/utsname.h> - -#include <ctype.h> -#include <err.h> -#include <errno.h> -#include <fcntl.h> -#include <limits.h> -#include <pwd.h> -#include <signal.h> -#include <stdlib.h> -#include <string.h> -#include <sysexits.h> -#include <syslog.h> -#include <unistd.h> - -#include "inetd.h" - -void chargen_dg(int, struct servtab *); -void chargen_stream(int, struct servtab *); -void daytime_dg(int, struct servtab *); -void daytime_stream(int, struct servtab *); -void discard_dg(int, struct servtab *); -void discard_stream(int, struct servtab *); -void echo_dg(int, struct servtab *); -void echo_stream(int, struct servtab *); -static int get_line(int, char *, int); -void iderror(int, int, int, const char *); -void ident_stream(int, struct servtab *); -void initring(void); -uint32_t machtime(void); -void machtime_dg(int, struct servtab *); -void machtime_stream(int, struct servtab *); - -char ring[128]; -char *endring; - - -struct biltin biltins[] = { - /* Echo received data */ - { "echo", SOCK_STREAM, 1, -1, echo_stream }, - { "echo", SOCK_DGRAM, 0, 1, echo_dg }, - - /* Internet /dev/null */ - { "discard", SOCK_STREAM, 1, -1, discard_stream }, - { "discard", SOCK_DGRAM, 0, 1, discard_dg }, - - /* Return 32 bit time since 1900 */ - { "time", SOCK_STREAM, 0, -1, machtime_stream }, - { "time", SOCK_DGRAM, 0, 1, machtime_dg }, - - /* Return human-readable time */ - { "daytime", SOCK_STREAM, 0, -1, daytime_stream }, - { "daytime", SOCK_DGRAM, 0, 1, daytime_dg }, - - /* Familiar character generator */ - { "chargen", SOCK_STREAM, 1, -1, chargen_stream }, - { "chargen", SOCK_DGRAM, 0, 1, chargen_dg }, - - { "tcpmux", SOCK_STREAM, 1, -1, (bi_fn_t *)tcpmux }, - - { "auth", SOCK_STREAM, 1, -1, ident_stream }, - - { NULL, 0, 0, 0, NULL } -}; - -/* - * RFC864 Character Generator Protocol. Generates character data without - * any regard for input. - */ - -void -initring(void) -{ - int i; - - endring = ring; - - for (i = 0; i <= 128; ++i) - if (isprint(i)) - *endring++ = i; -} - -/* Character generator - * The RFC says that we should send back a random number of - * characters chosen from the range 0 to 512. We send LINESIZ+2. - */ -/* ARGSUSED */ -void -chargen_dg(int s, struct servtab *sep) -{ - struct sockaddr_storage ss; - static char *rs; - int len; - socklen_t size; - char text[LINESIZ+2]; - - if (endring == 0) { - initring(); - rs = ring; - } - - size = sizeof(ss); - if (recvfrom(s, text, sizeof(text), 0, - (struct sockaddr *)&ss, &size) < 0) - return; - - if (check_loop((struct sockaddr *)&ss, sep)) - return; - - if ((len = endring - rs) >= LINESIZ) - memmove(text, rs, LINESIZ); - else { - memmove(text, rs, len); - memmove(text + len, ring, LINESIZ - len); - } - if (++rs == endring) - rs = ring; - text[LINESIZ] = '\r'; - text[LINESIZ + 1] = '\n'; - (void) sendto(s, text, sizeof(text), 0, (struct sockaddr *)&ss, size); -} - -/* Character generator */ -/* ARGSUSED */ -void -chargen_stream(int s, struct servtab *sep) -{ - int len; - char *rs, text[LINESIZ+2]; - - inetd_setproctitle(sep->se_service, s); - - if (!endring) { - initring(); - rs = ring; - } - - text[LINESIZ] = '\r'; - text[LINESIZ + 1] = '\n'; - for (rs = ring;;) { - if ((len = endring - rs) >= LINESIZ) - memmove(text, rs, LINESIZ); - else { - memmove(text, rs, len); - memmove(text + len, ring, LINESIZ - len); - } - if (++rs == endring) - rs = ring; - if (write(s, text, sizeof(text)) != sizeof(text)) - break; - } - exit(0); -} - -/* - * RFC867 Daytime Protocol. Sends the current date and time as an ascii - * character string without any regard for input. - */ - -/* Return human-readable time of day */ -/* ARGSUSED */ -void -daytime_dg(int s, struct servtab *sep) -{ - char buffer[256]; - time_t now; - struct sockaddr_storage ss; - socklen_t size; - - now = time((time_t *) 0); - - size = sizeof(ss); - if (recvfrom(s, buffer, sizeof(buffer), 0, - (struct sockaddr *)&ss, &size) < 0) - return; - - if (check_loop((struct sockaddr *)&ss, sep)) - return; - - (void) sprintf(buffer, "%.24s\r\n", ctime(&now)); - (void) sendto(s, buffer, strlen(buffer), 0, - (struct sockaddr *)&ss, size); -} - -/* Return human-readable time of day */ -/* ARGSUSED */ -void -daytime_stream(int s, struct servtab *sep __unused) -{ - char buffer[256]; - time_t now; - - now = time((time_t *) 0); - - (void) sprintf(buffer, "%.24s\r\n", ctime(&now)); - (void) send(s, buffer, strlen(buffer), MSG_EOF); -} - -/* - * RFC863 Discard Protocol. Any data received is thrown away and no response - * is sent. - */ - -/* Discard service -- ignore data */ -/* ARGSUSED */ -void -discard_dg(int s, struct servtab *sep __unused) -{ - char buffer[BUFSIZE]; - - (void) read(s, buffer, sizeof(buffer)); -} - -/* Discard service -- ignore data */ -/* ARGSUSED */ -void -discard_stream(int s, struct servtab *sep) -{ - int ret; - char buffer[BUFSIZE]; - - inetd_setproctitle(sep->se_service, s); - while (1) { - while ((ret = read(s, buffer, sizeof(buffer))) > 0) - ; - if (ret == 0 || errno != EINTR) - break; - } - exit(0); -} - -/* - * RFC862 Echo Protocol. Any data received is sent back to the sender as - * received. - */ - -/* Echo service -- echo data back */ -/* ARGSUSED */ -void -echo_dg(int s, struct servtab *sep) -{ - char buffer[65536]; /* Should be sizeof(max datagram). */ - int i; - socklen_t size; - struct sockaddr_storage ss; - - size = sizeof(ss); - if ((i = recvfrom(s, buffer, sizeof(buffer), 0, - (struct sockaddr *)&ss, &size)) < 0) - return; - - if (check_loop((struct sockaddr *)&ss, sep)) - return; - - (void) sendto(s, buffer, i, 0, (struct sockaddr *)&ss, size); -} - -/* Echo service -- echo data back */ -/* ARGSUSED */ -void -echo_stream(int s, struct servtab *sep) -{ - char buffer[BUFSIZE]; - int i; - - inetd_setproctitle(sep->se_service, s); - while ((i = read(s, buffer, sizeof(buffer))) > 0 && - write(s, buffer, i) > 0) - ; - exit(0); -} - -/* - * RFC1413 Identification Protocol. Given a TCP port number pair, return a - * character string which identifies the owner of that connection on the - * server's system. Extended to allow for ~/.fakeid support and ~/.noident - * support. - */ - -/* RFC 1413 says the following are the only errors you can return. */ -#define ID_INVALID "INVALID-PORT" /* Port number improperly specified. */ -#define ID_NOUSER "NO-USER" /* Port not in use/not identifable. */ -#define ID_HIDDEN "HIDDEN-USER" /* Hiden at user's request. */ -#define ID_UNKNOWN "UNKNOWN-ERROR" /* Everything else. */ - -/* Generic ident_stream error-sending func */ -/* ARGSUSED */ -void -iderror(int lport, int fport, int s, const char *er) -{ - char *p; - - asprintf(&p, "%d , %d : ERROR : %s\r\n", lport, fport, er); - if (p == NULL) { - syslog(LOG_ERR, "asprintf: %m"); - exit(EX_OSERR); - } - send(s, p, strlen(p), MSG_EOF); - free(p); - - exit(0); -} - -/* Ident service (AKA "auth") */ -/* ARGSUSED */ -void -ident_stream(int s, struct servtab *sep) -{ - struct utsname un; - struct stat sb; - struct sockaddr_in sin4[2]; -#ifdef INET6 - struct sockaddr_in6 sin6[2]; -#endif - struct sockaddr_storage ss[2]; - struct xucred uc; - struct timeval tv = { - 10, - 0 - }, to; - struct passwd *pw = NULL; - fd_set fdset; - char buf[BUFSIZE], *p, **av, *osname = NULL, e; - char idbuf[MAXLOGNAME] = ""; /* Big enough to hold uid in decimal. */ - socklen_t socklen; - ssize_t ssize; - size_t size, bufsiz; - int c, fflag = 0, nflag = 0, rflag = 0, argc = 0; - int gflag = 0, iflag = 0, Fflag = 0, getcredfail = 0, onreadlen; - u_short lport, fport; - - inetd_setproctitle(sep->se_service, s); - /* - * Reset getopt() since we are a fork() but not an exec() from - * a parent which used getopt() already. - */ - optind = 1; - optreset = 1; - /* - * Take the internal argument vector and count it out to make an - * argument count for getopt. This can be used for any internal - * service to read arguments and use getopt() easily. - */ - for (av = sep->se_argv; *av; av++) - argc++; - if (argc) { - int sec, usec; - size_t i; - u_int32_t rnd32; - - while ((c = getopt(argc, sep->se_argv, "d:fFgino:rt:")) != -1) - switch (c) { - case 'd': - if (!gflag) - strlcpy(idbuf, optarg, sizeof(idbuf)); - break; - case 'f': - fflag = 1; - break; - case 'F': - fflag = 1; - Fflag=1; - break; - case 'g': - gflag = 1; - rnd32 = 0; /* Shush, compiler. */ - /* - * The number of bits in "rnd32" divided - * by the number of bits needed per iteration - * gives a more optimal way to reload the - * random number only when necessary. - * - * 32 bits from arc4random corresponds to - * about 6 base-36 digits, so we reseed evey 6. - */ - for (i = 0; i < sizeof(idbuf) - 1; i++) { - static const char *const base36 = - "0123456789" - "abcdefghijklmnopqrstuvwxyz"; - if (i % 6 == 0) - rnd32 = arc4random(); - idbuf[i] = base36[rnd32 % 36]; - rnd32 /= 36; - } - idbuf[i] = '\0'; - break; - case 'i': - iflag = 1; - break; - case 'n': - nflag = 1; - break; - case 'o': - osname = optarg; - break; - case 'r': - rflag = 1; - break; - case 't': - switch (sscanf(optarg, "%d.%d", &sec, &usec)) { - case 2: - tv.tv_usec = usec; - /* FALLTHROUGH */ - case 1: - tv.tv_sec = sec; - break; - default: - if (debug) - warnx("bad -t argument"); - break; - } - break; - default: - break; - } - } - if (osname == NULL) { - if (uname(&un) == -1) - iderror(0, 0, s, ID_UNKNOWN); - osname = un.sysname; - } - - /* - * We're going to prepare for and execute reception of a - * packet of data from the user. The data is in the format - * "local_port , foreign_port\r\n" (with local being the - * server's port and foreign being the client's.) - */ - gettimeofday(&to, NULL); - to.tv_sec += tv.tv_sec; - to.tv_usec += tv.tv_usec; - if (to.tv_usec >= 1000000) { - to.tv_usec -= 1000000; - to.tv_sec++; - } - - size = 0; - bufsiz = sizeof(buf) - 1; - FD_ZERO(&fdset); - while (bufsiz > 0) { - gettimeofday(&tv, NULL); - tv.tv_sec = to.tv_sec - tv.tv_sec; - tv.tv_usec = to.tv_usec - tv.tv_usec; - if (tv.tv_usec < 0) { - tv.tv_usec += 1000000; - tv.tv_sec--; - } - if (tv.tv_sec < 0) - break; - FD_SET(s, &fdset); - if (select(s + 1, &fdset, NULL, NULL, &tv) == -1) - iderror(0, 0, s, ID_UNKNOWN); - if (ioctl(s, FIONREAD, &onreadlen) == -1) - iderror(0, 0, s, ID_UNKNOWN); - if ((size_t)onreadlen > bufsiz) - onreadlen = bufsiz; - ssize = read(s, &buf[size], (size_t)onreadlen); - if (ssize == -1) - iderror(0, 0, s, ID_UNKNOWN); - else if (ssize == 0) - break; - bufsiz -= ssize; - size += ssize; - if (memchr(&buf[size - ssize], '\n', ssize) != NULL) - break; - } - buf[size] = '\0'; - /* Read two characters, and check for a delimiting character */ - if (sscanf(buf, "%hu , %hu%c", &lport, &fport, &e) != 3 || isdigit(e)) - iderror(0, 0, s, ID_INVALID); - - /* Send garbage? */ - if (gflag) - goto printit; - - /* - * If not "real" (-r), send a HIDDEN-USER error for everything. - * If -d is used to set a fallback username, this is used to - * override it, and the fallback is returned instead. - */ - if (!rflag) { - if (*idbuf == '\0') - iderror(lport, fport, s, ID_HIDDEN); - goto printit; - } - - /* - * We take the input and construct an array of two sockaddr_ins - * which contain the local address information and foreign - * address information, respectively, used to look up the - * credentials for the socket (which are returned by the - * sysctl "net.inet.tcp.getcred" when we call it.) - */ - socklen = sizeof(ss[0]); - if (getsockname(s, (struct sockaddr *)&ss[0], &socklen) == -1) - iderror(lport, fport, s, ID_UNKNOWN); - socklen = sizeof(ss[1]); - if (getpeername(s, (struct sockaddr *)&ss[1], &socklen) == -1) - iderror(lport, fport, s, ID_UNKNOWN); - if (ss[0].ss_family != ss[1].ss_family) - iderror(lport, fport, s, ID_UNKNOWN); - size = sizeof(uc); - switch (ss[0].ss_family) { - case AF_INET: - sin4[0] = *(struct sockaddr_in *)&ss[0]; - sin4[0].sin_port = htons(lport); - sin4[1] = *(struct sockaddr_in *)&ss[1]; - sin4[1].sin_port = htons(fport); - if (sysctlbyname("net.inet.tcp.getcred", &uc, &size, sin4, - sizeof(sin4)) == -1) - getcredfail = errno; - break; -#ifdef INET6 - case AF_INET6: - sin6[0] = *(struct sockaddr_in6 *)&ss[0]; - sin6[0].sin6_port = htons(lport); - sin6[1] = *(struct sockaddr_in6 *)&ss[1]; - sin6[1].sin6_port = htons(fport); - if (sysctlbyname("net.inet6.tcp6.getcred", &uc, &size, sin6, - sizeof(sin6)) == -1) - getcredfail = errno; - break; -#endif - default: /* should not reach here */ - getcredfail = EAFNOSUPPORT; - break; - } - if (getcredfail != 0 || uc.cr_version != XUCRED_VERSION) { - if (*idbuf == '\0') - iderror(lport, fport, s, - getcredfail == ENOENT ? ID_NOUSER : ID_UNKNOWN); - goto printit; - } - - /* Look up the pw to get the username and home directory*/ - errno = 0; - pw = getpwuid(uc.cr_uid); - if (pw == NULL) - iderror(lport, fport, s, errno == 0 ? ID_NOUSER : ID_UNKNOWN); - - if (iflag) - snprintf(idbuf, sizeof(idbuf), "%u", (unsigned)pw->pw_uid); - else - strlcpy(idbuf, pw->pw_name, sizeof(idbuf)); - - /* - * If enabled, we check for a file named ".noident" in the user's - * home directory. If found, we return HIDDEN-USER. - */ - if (nflag) { - if (asprintf(&p, "%s/.noident", pw->pw_dir) == -1) - iderror(lport, fport, s, ID_UNKNOWN); - if (lstat(p, &sb) == 0) { - free(p); - iderror(lport, fport, s, ID_HIDDEN); - } - free(p); - } - - /* - * Here, if enabled, we read a user's ".fakeid" file in their - * home directory. It consists of a line containing the name - * they want. - */ - if (fflag) { - int fakeid_fd; - - /* - * Here we set ourself to effectively be the user, so we don't - * open any files we have no permission to open, especially - * symbolic links to sensitive root-owned files or devices. - */ - if (initgroups(pw->pw_name, pw->pw_gid) == -1) - iderror(lport, fport, s, ID_UNKNOWN); - if (seteuid(pw->pw_uid) == -1) - iderror(lport, fport, s, ID_UNKNOWN); - /* - * We can't stat() here since that would be a race - * condition. - * Therefore, we open the file we have permissions to open - * and if it's not a regular file, we close it and end up - * returning the user's real username. - */ - if (asprintf(&p, "%s/.fakeid", pw->pw_dir) == -1) - iderror(lport, fport, s, ID_UNKNOWN); - fakeid_fd = open(p, O_RDONLY | O_NONBLOCK); - free(p); - if (fakeid_fd == -1 || fstat(fakeid_fd, &sb) == -1 || - !S_ISREG(sb.st_mode)) - goto fakeid_fail; - - if ((ssize = read(fakeid_fd, buf, sizeof(buf) - 1)) < 0) - goto fakeid_fail; - buf[ssize] = '\0'; - - /* - * Usually, the file will have the desired identity - * in the form "identity\n". Allow for leading white - * space and trailing white space/end of line. - */ - p = buf; - p += strspn(p, " \t"); - p[strcspn(p, " \t\r\n")] = '\0'; - if (strlen(p) > MAXLOGNAME - 1) /* Too long (including nul)? */ - p[MAXLOGNAME - 1] = '\0'; - - /* - * If the name is a zero-length string or matches it - * the id or name of another user (unless permitted by -F) - * then it is invalid. - */ - if (*p == '\0') - goto fakeid_fail; - if (!Fflag) { - if (iflag) { - if (p[strspn(p, "0123456789")] == '\0' && - getpwuid(atoi(p)) != NULL) - goto fakeid_fail; - } else { - if (getpwnam(p) != NULL) - goto fakeid_fail; - } - } - - strlcpy(idbuf, p, sizeof(idbuf)); - -fakeid_fail: - if (fakeid_fd != -1) - close(fakeid_fd); - } - -printit: - /* Finally, we make and send the reply. */ - if (asprintf(&p, "%d , %d : USERID : %s : %s\r\n", lport, fport, osname, - idbuf) == -1) { - syslog(LOG_ERR, "asprintf: %m"); - exit(EX_OSERR); - } - send(s, p, strlen(p), MSG_EOF); - free(p); - - exit(0); -} - -/* - * RFC738/868 Time Server. - * Return a machine readable date and time, in the form of the - * number of seconds since midnight, Jan 1, 1900. Since gettimeofday - * returns the number of seconds since midnight, Jan 1, 1970, - * we must add 2208988800 seconds to this figure to make up for - * some seventy years Bell Labs was asleep. - */ - -uint32_t -machtime(void) -{ - -#define OFFSET ((uint32_t)25567 * 24*60*60) - return (htonl((uint32_t)(time(NULL) + OFFSET))); -#undef OFFSET -} - -/* ARGSUSED */ -void -machtime_dg(int s, struct servtab *sep) -{ - uint32_t result; - struct sockaddr_storage ss; - socklen_t size; - - size = sizeof(ss); - if (recvfrom(s, (char *)&result, sizeof(result), 0, - (struct sockaddr *)&ss, &size) < 0) - return; - - if (check_loop((struct sockaddr *)&ss, sep)) - return; - - result = machtime(); - (void) sendto(s, (char *) &result, sizeof(result), 0, - (struct sockaddr *)&ss, size); -} - -/* ARGSUSED */ -void -machtime_stream(int s, struct servtab *sep __unused) -{ - uint32_t result; - - result = machtime(); - (void) send(s, (char *) &result, sizeof(result), MSG_EOF); -} - -/* - * RFC1078 TCP Port Service Multiplexer (TCPMUX). Service connections to - * services based on the service name sent. - * - * Based on TCPMUX.C by Mark K. Lottor November 1988 - * sri-nic::ps:<mkl>tcpmux.c - */ - -#define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */ -#define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1) - -static int /* # of characters up to \r,\n or \0 */ -get_line(int fd, char *buf, int len) -{ - int count = 0, n; - struct sigaction sa; - - sa.sa_flags = 0; - sigemptyset(&sa.sa_mask); - sa.sa_handler = SIG_DFL; - sigaction(SIGALRM, &sa, (struct sigaction *)0); - do { - alarm(10); - n = read(fd, buf, len-count); - alarm(0); - if (n == 0) - return (count); - if (n < 0) - return (-1); - while (--n >= 0) { - if (*buf == '\r' || *buf == '\n' || *buf == '\0') - return (count); - count++; - buf++; - } - } while (count < len); - return (count); -} - -struct servtab * -tcpmux(int s) -{ - struct servtab *sep; - char service[MAX_SERV_LEN+1]; - int len; - - /* Get requested service name */ - if ((len = get_line(s, service, MAX_SERV_LEN)) < 0) { - strwrite(s, "-Error reading service name\r\n"); - return (NULL); - } - service[len] = '\0'; - - if (debug) - warnx("tcpmux: someone wants %s", service); - - /* - * Help is a required command, and lists available services, - * one per line. - */ - if (!strcasecmp(service, "help")) { - for (sep = servtab; sep; sep = sep->se_next) { - if (!ISMUX(sep)) - continue; - (void)write(s,sep->se_service,strlen(sep->se_service)); - strwrite(s, "\r\n"); - } - return (NULL); - } - - /* Try matching a service in inetd.conf with the request */ - for (sep = servtab; sep; sep = sep->se_next) { - if (!ISMUX(sep)) - continue; - if (!strcasecmp(service, sep->se_service)) { - if (ISMUXPLUS(sep)) { - strwrite(s, "+Go\r\n"); - } - return (sep); - } - } - strwrite(s, "-Service not available\r\n"); - return (NULL); -} |
