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authorDaniel Stenberg <daniel@haxx.se>2005-09-15 20:32:59 +0000
committerDaniel Stenberg <daniel@haxx.se>2005-09-15 20:32:59 +0000
commitcd5de5c0e51cb473f06b9157a03b6a28529b25bf (patch)
treed9f4da783ab1f38e31437c85c04a062afca4b2b1 /tests
parentbd5afc26bd0fe5dc19202d1faa4ef87993c54889 (diff)
downloadcurl-cd5de5c0e51cb473f06b9157a03b6a28529b25bf.tar.gz
First version of the TFTP server. Basic functionality is there.
Diffstat (limited to 'tests')
-rw-r--r--tests/server/tftpd.c865
1 files changed, 865 insertions, 0 deletions
diff --git a/tests/server/tftpd.c b/tests/server/tftpd.c
new file mode 100644
index 000000000..f122c9b1e
--- /dev/null
+++ b/tests/server/tftpd.c
@@ -0,0 +1,865 @@
+/***************************************************************************
+ * _ _ ____ _
+ * 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");
+}