curl/tests/server/tftpd.c

866 lines
22 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* $Id$
*
* Trivial file transfer protocol server.
*
* This code includes many modifications by Jim Guyton <guyton@rand-unix>
*
* This source file was started based on netkit-tftpd 0.17
* Heavily modified for curl's test suite
*/
/*
* Copyright (c) 1983 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 "setup.h" /* portability help from the lib directory */
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <signal.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/tftp.h>
#include <netdb.h>
#include <setjmp.h>
#include <stdio.h>
#include <errno.h>
#include <ctype.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <pwd.h>
#include <grp.h>
#include "getpart.h"
#include "util.h"
struct testcase {
char *buffer; /* holds the file data to send to the client */
size_t bufsize; /* size of the data in buffer */
char *rptr; /* read pointer into the buffer */
size_t rcount; /* amount of data left to read of the file */
long num; /* test case number */
int ofile; /* file descriptor for output file when uploading to us */
FILE *server; /* write input "protocol" there for client verification */
};
static int synchnet(int);
static struct tftphdr *r_init(void);
static struct tftphdr *w_init(void);
static int readit(struct testcase *test, struct tftphdr **dpp, int convert);
static int writeit(struct testcase *test, struct tftphdr **dpp, int ct,
int convert);
static void mysignal(int, void (*func)(int));
#define TIMEOUT 5
#define PKTSIZE SEGSIZE+4
struct formats;
static int tftp(struct testcase *test, struct tftphdr *tp, int size);
static void nak(int error);
static void sendfile(struct testcase *test, struct formats *pf);
static void recvfile(struct testcase *test, struct formats *pf);
static int validate_access(struct testcase *test, const char *, int);
static curl_socket_t peer;
static int rexmtval = TIMEOUT;
static int maxtimeout = 5*TIMEOUT;
static char buf[PKTSIZE];
static char ackbuf[PKTSIZE];
static struct sockaddr_in from;
static socklen_t fromlen;
struct bf {
int counter; /* size of data in buffer, or flag */
char buf[PKTSIZE]; /* room for data packet */
} bfs[2];
/* Values for bf.counter */
#define BF_ALLOC -3 /* alloc'd but not yet filled */
#define BF_FREE -2 /* free */
/* [-1 .. SEGSIZE] = size of data in the data buffer */
static int nextone; /* index of next buffer to use */
static int current; /* index of buffer in use */
/* control flags for crlf conversions */
int newline = 0; /* fillbuf: in middle of newline expansion */
int prevchar = -1; /* putbuf: previous char (cr check) */
static void read_ahead(struct testcase *test,
int convert /* if true, convert to ascii */);
static int write_behind(struct testcase *test, int convert);
static struct tftphdr *rw_init(int);
static struct tftphdr *w_init(void) { return rw_init(0); } /* write-behind */
static struct tftphdr *r_init(void) { return rw_init(1); } /* read-ahead */
static struct tftphdr *
rw_init(int x) /* init for either read-ahead or write-behind */
{ /* zero for write-behind, one for read-head */
newline = 0; /* init crlf flag */
prevchar = -1;
bfs[0].counter = BF_ALLOC; /* pass out the first buffer */
current = 0;
bfs[1].counter = BF_FREE;
nextone = x; /* ahead or behind? */
return (struct tftphdr *)bfs[0].buf;
}
/* Have emptied current buffer by sending to net and getting ack.
Free it and return next buffer filled with data.
*/
static int readit(struct testcase *test, struct tftphdr **dpp,
int convert /* if true, convert to ascii */)
{
struct bf *b;
bfs[current].counter = BF_FREE; /* free old one */
current = !current; /* "incr" current */
b = &bfs[current]; /* look at new buffer */
if (b->counter == BF_FREE) /* if it's empty */
read_ahead(test, convert); /* fill it */
*dpp = (struct tftphdr *)b->buf; /* set caller's ptr */
return b->counter;
}
#define MIN(x,y) ((x)<(y)?(x):(y));
/*
* fill the input buffer, doing ascii conversions if requested
* conversions are lf -> cr,lf and cr -> cr, nul
*/
static void read_ahead(struct testcase *test,
int convert /* if true, convert to ascii */)
{
int i;
char *p;
int c;
struct bf *b;
struct tftphdr *dp;
b = &bfs[nextone]; /* look at "next" buffer */
if (b->counter != BF_FREE) /* nop if not free */
return;
nextone = !nextone; /* "incr" next buffer ptr */
dp = (struct tftphdr *)b->buf;
if (convert == 0) {
/* The former file reading code did this:
b->counter = read(fileno(file), dp->th_data, SEGSIZE); */
int copy_n = MIN(SEGSIZE, test->rcount);
memcpy(dp->th_data, test->rptr, copy_n);
/* decrease amount, advance pointer */
test->rcount -= copy_n;
test->rptr += copy_n;
b->counter = copy_n;
return;
}
p = dp->th_data;
for (i = 0 ; i < SEGSIZE; i++) {
if (newline) {
if (prevchar == '\n')
c = '\n'; /* lf to cr,lf */
else
c = '\0'; /* cr to cr,nul */
newline = 0;
}
else {
if(test->rcount) {
c=test->rptr[0];
test->rptr++;
test->rcount--;
}
else
break;
if (c == '\n' || c == '\r') {
prevchar = c;
c = '\r';
newline = 1;
}
}
*p++ = c;
}
b->counter = (int)(p - dp->th_data);
}
/* Update count associated with the buffer, get new buffer from the queue.
Calls write_behind only if next buffer not available.
*/
static int writeit(struct testcase *test, struct tftphdr **dpp,
int ct, int convert)
{
bfs[current].counter = ct; /* set size of data to write */
current = !current; /* switch to other buffer */
if (bfs[current].counter != BF_FREE) /* if not free */
write_behind(test, convert); /* flush it */
bfs[current].counter = BF_ALLOC; /* mark as alloc'd */
*dpp = (struct tftphdr *)bfs[current].buf;
return ct; /* this is a lie of course */
}
/*
* Output a buffer to a file, converting from netascii if requested.
* CR,NUL -> CR and CR,LF => LF.
* Note spec is undefined if we get CR as last byte of file or a
* CR followed by anything else. In this case we leave it alone.
*/
static int write_behind(struct testcase *test, int convert)
{
char *buf;
int count;
int ct;
char *p;
int c; /* current character */
struct bf *b;
struct tftphdr *dp;
b = &bfs[nextone];
if (b->counter < -1) /* anything to flush? */
return 0; /* just nop if nothing to do */
if(!test->ofile) {
char outfile[256];
snprintf(outfile, sizeof(outfile), "log/upload.%ld", test->num);
test->ofile=open(outfile, O_CREAT|O_RDWR, 0777);
if(test->ofile == -1) {
logmsg("Couldn't create and/or open file %s for upload!", outfile);
return -1; /* failure! */
}
}
count = b->counter; /* remember byte count */
b->counter = BF_FREE; /* reset flag */
dp = (struct tftphdr *)b->buf;
nextone = !nextone; /* incr for next time */
buf = dp->th_data;
if (count <= 0)
return -1; /* nak logic? */
if (convert == 0)
return write(test->ofile, buf, count);
p = buf;
ct = count;
while (ct--) { /* loop over the buffer */
c = *p++; /* pick up a character */
if (prevchar == '\r') { /* if prev char was cr */
if (c == '\n') /* if have cr,lf then just */
lseek(test->ofile, -1, SEEK_CUR); /* smash lf on top of the cr */
else
if (c == '\0') /* if have cr,nul then */
goto skipit; /* just skip over the putc */
/* else just fall through and allow it */
}
/* formerly
putc(c, file); */
write(test->ofile, &c, 1);
skipit:
prevchar = c;
}
return count;
}
/* When an error has occurred, it is possible that the two sides are out of
* synch. Ie: that what I think is the other side's response to packet N is
* really their response to packet N-1.
*
* So, to try to prevent that, we flush all the input queued up for us on the
* network connection on our host.
*
* We return the number of packets we flushed (mostly for reporting when trace
* is active).
*/
static int synchnet(curl_socket_t f /* socket to flush */)
{
int i, j = 0;
char rbuf[PKTSIZE];
struct sockaddr_in from;
socklen_t fromlen;
while (1) {
(void) ioctl(f, FIONREAD, &i);
if (i) {
j++;
fromlen = sizeof from;
(void) recvfrom(f, rbuf, sizeof (rbuf), 0,
(struct sockaddr *)&from, &fromlen);
}
else
return j;
}
}
/*
* Like signal(), but with well-defined semantics.
*/
static void mysignal(int sig, void (*handler)(int))
{
struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.sa_handler = handler;
sigaction(sig, &sa, NULL);
}
#ifndef DEFAULT_LOGFILE
#define DEFAULT_LOGFILE "log/tftpd.log"
#endif
#define DEFAULT_PORT 8999 /* UDP */
const char *serverlogfile = DEFAULT_LOGFILE;
#define REQUEST_DUMP "log/server.input"
char use_ipv6=FALSE;
int main(int argc, char **argv)
{
struct sockaddr_in me;
#ifdef ENABLE_IPV6
struct sockaddr_in6 me6;
#endif /* ENABLE_IPV6 */
struct tftphdr *tp;
int n = 0;
int arg = 1;
FILE *pidfile;
char *pidname= (char *)".tftpd.pid";
unsigned short port = DEFAULT_PORT;
curl_socket_t sock;
int flag;
int rc;
struct testcase test;
while(argc>arg) {
if(!strcmp("--version", argv[arg])) {
printf("tftpd IPv4%s\n",
#ifdef ENABLE_IPV6
"/IPv6"
#else
""
#endif
);
return 0;
}
else if(!strcmp("--pidfile", argv[arg])) {
arg++;
if(argc>arg)
pidname = argv[arg++];
}
else if(!strcmp("--ipv6", argv[arg])) {
#ifdef ENABLE_IPV6
use_ipv6=TRUE;
#endif
arg++;
}
else if(argc>arg) {
if(atoi(argv[arg]))
port = (unsigned short)atoi(argv[arg++]);
if(argc>arg)
path = argv[arg++];
}
}
#if defined(WIN32) && !defined(__GNUC__) || defined(__MINGW32__)
win32_init();
atexit(win32_cleanup);
#endif
#ifdef ENABLE_IPV6
if(!use_ipv6)
#endif
sock = socket(AF_INET, SOCK_DGRAM, 0);
#ifdef ENABLE_IPV6
else
sock = socket(AF_INET6, SOCK_DGRAM, 0);
#endif
if (sock < 0) {
perror("opening stream socket");
logmsg("Error opening socket");
exit(1);
}
flag = 1;
if (setsockopt
(sock, SOL_SOCKET, SO_REUSEADDR, (const void *) &flag,
sizeof(int)) < 0) {
perror("setsockopt(SO_REUSEADDR)");
}
#ifdef ENABLE_IPV6
if(!use_ipv6) {
#endif
me.sin_family = AF_INET;
me.sin_addr.s_addr = INADDR_ANY;
me.sin_port = htons(port);
rc = bind(sock, (struct sockaddr *) &me, sizeof(me));
#ifdef ENABLE_IPV6
}
else {
memset(&me6, 0, sizeof(struct sockaddr_in6));
me6.sin6_family = AF_INET6;
me6.sin6_addr = in6addr_any;
me6.sin6_port = htons(port);
rc = bind(sock, (struct sockaddr *) &me6, sizeof(me6));
}
#endif /* ENABLE_IPV6 */
if(rc < 0) {
perror("binding stream socket");
logmsg("Error binding socket");
exit(1);
}
pidfile = fopen(pidname, "w");
if(pidfile) {
fprintf(pidfile, "%d\n", (int)getpid());
fclose(pidfile);
}
else
fprintf(stderr, "Couldn't write pid file\n");
logmsg("Running IPv%d version on port UDP/%d",
#ifdef ENABLE_IPV6
(use_ipv6?6:4)
#else
4
#endif
, port );
do {
FILE *server;
server = fopen(REQUEST_DUMP, "ab");
if(!server)
break;
fromlen = sizeof(from);
n = recvfrom(sock, buf, sizeof (buf), 0,
(struct sockaddr *)&from, &fromlen);
if (n < 0) {
logmsg("recvfrom:\n");
return 3;
}
from.sin_family = AF_INET;
peer = socket(AF_INET, SOCK_DGRAM, 0);
if (peer < 0) {
logmsg("socket:\n");
return 2;
}
if (connect(peer, (struct sockaddr *)&from, sizeof(from)) < 0) {
logmsg("connect: fail\n");
return 1;
}
tp = (struct tftphdr *)buf;
tp->th_opcode = ntohs(tp->th_opcode);
if (tp->th_opcode == RRQ || tp->th_opcode == WRQ) {
memset(&test, 0, sizeof(test));
test.server = server;
tftp(&test, tp, n);
}
fclose(server);
sclose(peer);
} while(1);
return 0;
}
struct formats {
const char *f_mode;
int f_convert;
} formats[] = {
{ "netascii", 1 },
{ "octet", 0 },
{ NULL, 0 }
};
/*
* Handle initial connection protocol.
*/
static int tftp(struct testcase *test, struct tftphdr *tp, int size)
{
char *cp;
int first = 1, ecode;
struct formats *pf;
char *filename, *mode = NULL;
/* store input protocol */
fprintf(test->server, "opcode: %x\n", tp->th_opcode);
filename = cp = tp->th_stuff;
again:
while (cp < buf + size) {
if (*cp == '\0')
break;
cp++;
}
if (*cp) {
nak(EBADOP);
return 3;
}
if (first) {
mode = ++cp;
first = 0;
goto again;
}
/* store input protocol */
fprintf(test->server, "filename: %s\n", filename);
for (cp = mode; *cp; cp++)
if (isupper(*cp))
*cp = tolower(*cp);
/* store input protocol */
fprintf(test->server, "mode: %s\n", mode);
for (pf = formats; pf->f_mode; pf++)
if (strcmp(pf->f_mode, mode) == 0)
break;
if (!pf->f_mode) {
nak(EBADOP);
return 2;
}
ecode = validate_access(test, filename, tp->th_opcode);
if (ecode) {
nak(ecode);
return 1;
}
if (tp->th_opcode == WRQ)
recvfile(test, pf);
else
sendfile(test, pf);
return 0;
}
/*
* Validate file access.
*/
static int validate_access(struct testcase *test,
const char *filename, int mode)
{
char *ptr;
long testno;
logmsg("trying to get file: %s mode %x", filename, mode);
if(!strncmp("/verifiedserver", filename, 15)) {
char weare[128];
size_t count = sprintf(weare, "WE ROOLZ: %d\r\n", (int)getpid());
logmsg("Are-we-friendly question received");
test->buffer = strdup(weare);
test->rptr = test->buffer; /* set read pointer */
test->bufsize = count; /* set total count */
test->rcount = count; /* set data left to read */
return 0; /* fine */
}
/* find the last slash */
ptr = strrchr(filename, '/');
if(ptr) {
char *file;
ptr++; /* skip the slash */
/* skip all non-numericals following the slash */
while(*ptr && !isdigit((int)*ptr))
ptr++;
/* get the number */
testno = strtol(ptr, &ptr, 10);
logmsg("requested test number %d", testno);
test->num = testno;
file = test2file(testno);
if(file) {
FILE *stream=fopen(file, "rb");
if(!stream) {
logmsg("Couldn't open test file: %s", file);
return EACCESS;
}
else {
size_t count;
test->buffer = (char *)spitout(stream, "reply", "data", &count);
fclose(stream);
if(test->buffer) {
test->rptr = test->buffer; /* set read pointer */
test->bufsize = count; /* set total count */
test->rcount = count; /* set data left to read */
}
else
return EACCESS;
}
}
else
return EACCESS;
}
else {
logmsg("no slash found in path");
return EACCESS; /* failure */
}
return 0;
}
int timeout;
sigjmp_buf timeoutbuf;
static void timer(int signum)
{
(void)signum;
timeout += rexmtval;
if (timeout >= maxtimeout)
exit(1);
siglongjmp(timeoutbuf, 1);
}
/*
* Send the requested file.
*/
static void sendfile(struct testcase *test, struct formats *pf)
{
struct tftphdr *dp;
struct tftphdr *ap; /* ack packet */
u_int16_t block = 1;
int size, n;
mysignal(SIGALRM, timer);
dp = r_init();
ap = (struct tftphdr *)ackbuf;
do {
size = readit(test, &dp, pf->f_convert);
if (size < 0) {
nak(errno + 100);
goto abort;
}
dp->th_opcode = htons((u_short)DATA);
dp->th_block = htons((u_short)block);
timeout = 0;
(void) sigsetjmp(timeoutbuf, 1);
send_data:
if (send(peer, dp, size + 4, 0) != size + 4) {
logmsg("write\n");
goto abort;
}
read_ahead(test, pf->f_convert);
for ( ; ; ) {
alarm(rexmtval); /* read the ack */
n = recv(peer, ackbuf, sizeof (ackbuf), 0);
alarm(0);
if (n < 0) {
logmsg("read: fail\n");
goto abort;
}
ap->th_opcode = ntohs((u_short)ap->th_opcode);
ap->th_block = ntohs((u_short)ap->th_block);
if (ap->th_opcode == ERROR)
goto abort;
if (ap->th_opcode == ACK) {
if (ap->th_block == block) {
break;
}
/* Re-synchronize with the other side */
(void) synchnet(peer);
if (ap->th_block == (block -1)) {
goto send_data;
}
}
}
block++;
} while (size == SEGSIZE);
abort:
;
}
static void justquit(int signum)
{
(void)signum;
exit(0);
}
/*
* Receive a file.
*/
static void recvfile(struct testcase *test, struct formats *pf)
{
struct tftphdr *dp;
struct tftphdr *ap; /* ack buffer */
u_int16_t block = 0;
int n, size;
mysignal(SIGALRM, timer);
dp = w_init();
ap = (struct tftphdr *)ackbuf;
do {
timeout = 0;
ap->th_opcode = htons((u_short)ACK);
ap->th_block = htons((u_short)block);
block++;
(void) sigsetjmp(timeoutbuf, 1);
send_ack:
if (send(peer, ackbuf, 4, 0) != 4) {
logmsg("write: fail\n");
goto abort;
}
write_behind(test, pf->f_convert);
for ( ; ; ) {
alarm(rexmtval);
n = recv(peer, dp, PKTSIZE, 0);
alarm(0);
if (n < 0) { /* really? */
logmsg("read: fail\n");
goto abort;
}
dp->th_opcode = ntohs((u_short)dp->th_opcode);
dp->th_block = ntohs((u_short)dp->th_block);
if (dp->th_opcode == ERROR)
goto abort;
if (dp->th_opcode == DATA) {
if (dp->th_block == block) {
break; /* normal */
}
/* Re-synchronize with the other side */
(void) synchnet(peer);
if (dp->th_block == (block-1))
goto send_ack; /* rexmit */
}
}
size = writeit(test, &dp, n - 4, pf->f_convert);
if (size != (n-4)) { /* ahem */
if (size < 0)
nak(errno + 100);
else
nak(ENOSPACE);
goto abort;
}
} while (size == SEGSIZE);
write_behind(test, pf->f_convert);
ap->th_opcode = htons((u_short)ACK); /* send the "final" ack */
ap->th_block = htons((u_short)(block));
(void) send(peer, ackbuf, 4, 0);
mysignal(SIGALRM, justquit); /* just quit on timeout */
alarm(rexmtval);
n = recv(peer, buf, sizeof (buf), 0); /* normally times out and quits */
alarm(0);
if (n >= 4 && /* if read some data */
dp->th_opcode == DATA && /* and got a data block */
block == dp->th_block) { /* then my last ack was lost */
(void) send(peer, ackbuf, 4, 0); /* resend final ack */
}
abort:
return;
}
struct errmsg {
int e_code;
const char *e_msg;
} errmsgs[] = {
{ EUNDEF, "Undefined error code" },
{ ENOTFOUND, "File not found" },
{ EACCESS, "Access violation" },
{ ENOSPACE, "Disk full or allocation exceeded" },
{ EBADOP, "Illegal TFTP operation" },
{ EBADID, "Unknown transfer ID" },
{ EEXISTS, "File already exists" },
{ ENOUSER, "No such user" },
{ -1, 0 }
};
/*
* Send a nak packet (error message). Error code passed in is one of the
* standard TFTP codes, or a UNIX errno offset by 100.
*/
static void nak(int error)
{
struct tftphdr *tp;
int length;
struct errmsg *pe;
tp = (struct tftphdr *)buf;
tp->th_opcode = htons((u_short)ERROR);
tp->th_code = htons((u_short)error);
for (pe = errmsgs; pe->e_code >= 0; pe++)
if (pe->e_code == error)
break;
if (pe->e_code < 0) {
pe->e_msg = strerror(error - 100);
tp->th_code = EUNDEF; /* set 'undef' errorcode */
}
strcpy(tp->th_msg, pe->e_msg);
length = strlen(pe->e_msg);
tp->th_msg[length] = '\0';
length += 5;
if (send(peer, buf, length, 0) != length)
logmsg("nak: fail\n");
}