/*************************************************************************** * _ _ ____ _ * 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 */ #ifdef HAVE_SYS_IOCTL_H #include <sys/ioctl.h> #endif #ifdef HAVE_SIGNAL_H #include <signal.h> #endif #ifdef HAVE_FCNTL_H #include <fcntl.h> #endif #ifdef HAVE_SYS_SOCKET_H #include <sys/socket.h> #endif #ifdef HAVE_NETINET_IN_H #include <netinet/in.h> #endif #ifdef HAVE_ARPA_TFTP_H #include <arpa/tftp.h> #else #include "tftp.h" #endif #ifdef HAVE_NETDB_H #include <netdb.h> #endif #ifdef HAVE_SYS_FILIO_H /* FIONREAD on Solaris 7 */ #include <sys/filio.h> #endif #include <setjmp.h> #ifdef HAVE_UNISTD_H #include <unistd.h> #endif #ifdef HAVE_PWD_H #include <pwd.h> #endif #define ENABLE_CURLX_PRINTF /* make the curlx header define all printf() functions to use the curlx_* versions instead */ #include "curlx.h" /* from the private lib dir */ #include "getpart.h" #include "util.h" /* include memdebug.h last */ #include "memdebug.h" #ifdef ENABLE_IPV6 static bool use_ipv6 = FALSE; #endif static const char *ipv_inuse = "IPv4"; 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 */ }; static int synchnet(curl_socket_t); 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 opcode_RRQ 1 #define opcode_WRQ 2 #define opcode_DATA 3 #define opcode_ACK 4 #define opcode_ERROR 5 #define TIMEOUT 5 #define PKTSIZE SEGSIZE+4 struct formats { const char *f_mode; int f_convert; }; static struct formats formata[] = { { "netascii", 1 }, { "octet", 0 }, { NULL, 0 } }; static int tftp(struct testcase *test, struct tftphdr *tp, ssize_t size); static void nak(int error); static void sendtftp(struct testcase *test, struct formats *pf); static void recvtftp(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 */ }; static struct bf 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 */ static int newline = 0; /* fillbuf: in middle of newline expansion */ static int prevchar = -1; /* putbuf: previous char (cr check) */ static void read_ahead(struct testcase *test, int convert /* if true, convert to ascii */); static ssize_t 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; } #undef MIN /* some systems have this defined already, some don't */ #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); */ size_t 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 = (int)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++ = (char)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 ssize_t write_behind(struct testcase *test, int convert) { char *writebuf; 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 */ writebuf = dp->th_data; if (count <= 0) return -1; /* nak logic? */ if (convert == 0) return write(test->ofile, writebuf, count); p = writebuf; 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 */) { #if defined(HAVE_IOCTLSOCKET) unsigned long i; #else int i; #endif int j = 0; char rbuf[PKTSIZE]; struct sockaddr_in fromaddr; socklen_t fromaddrlen; while (1) { #if defined(HAVE_IOCTLSOCKET) (void) ioctlsocket(f, FIONREAD, &i); #else (void) ioctl(f, FIONREAD, &i); #endif if (i) { j++; fromaddrlen = sizeof(fromaddr); (void)recvfrom(f, rbuf, sizeof(rbuf), 0, (struct sockaddr *)&fromaddr, &fromaddrlen); } else break; } return j; } #if defined(HAVE_ALARM) && defined(SIGALRM) /* * 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); } #endif #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" int main(int argc, char **argv) { struct sockaddr_in me; #ifdef ENABLE_IPV6 struct sockaddr_in6 me6; #endif /* ENABLE_IPV6 */ struct tftphdr *tp; ssize_t n = 0; int arg = 1; char *pidname= (char *)".tftpd.pid"; unsigned short port = DEFAULT_PORT; curl_socket_t sock; int flag; int rc; struct testcase test; int result = 0; 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 ipv_inuse = "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++]; } } #ifdef WIN32 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"); return 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"); sclose(sock); return 1; } if(!write_pidfile(pidname)) { sclose(sock); return 1; } logmsg("Running %s version on port UDP/%d", ipv_inuse, (int)port); do { fromlen = sizeof(from); n = (ssize_t)recvfrom(sock, buf, sizeof(buf), 0, (struct sockaddr *)&from, &fromlen); if (n < 0) { logmsg("recvfrom:\n"); result = 3; break; } set_advisor_read_lock(SERVERLOGS_LOCK); from.sin_family = AF_INET; peer = socket(AF_INET, SOCK_DGRAM, 0); if (peer < 0) { logmsg("socket:\n"); result = 2; break; } if (connect(peer, (struct sockaddr *)&from, sizeof(from)) < 0) { logmsg("connect: fail\n"); result = 1; break; } maxtimeout = 5*TIMEOUT; tp = (struct tftphdr *)buf; tp->th_opcode = ntohs(tp->th_opcode); if (tp->th_opcode == opcode_RRQ || tp->th_opcode == opcode_WRQ) { memset(&test, 0, sizeof(test)); if (tftp(&test, tp, n) < 0) break; if(test.buffer) free(test.buffer); } sclose(peer); clear_advisor_read_lock(SERVERLOGS_LOCK); } while(1); clear_advisor_read_lock(SERVERLOGS_LOCK); return result; } /* * Handle initial connection protocol. */ static int tftp(struct testcase *test, struct tftphdr *tp, ssize_t size) { char *cp; int first = 1, ecode; struct formats *pf; char *filename, *mode = NULL; int error; FILE *server; /* Open request dump file. */ server = fopen(REQUEST_DUMP, "ab"); if(!server) { error = ERRNO; logmsg("fopen() failed with error: %d %s", error, strerror(error)); logmsg("Error opening file: %s", REQUEST_DUMP); return -1; } /* store input protocol */ fprintf(server, "opcode: %x\n", tp->th_opcode); cp = (char *)&tp->th_stuff; filename = cp; again: while (cp < buf + size) { if (*cp == '\0') break; cp++; } if (*cp) { nak(EBADOP); fclose(server); return 3; } if (first) { mode = ++cp; first = 0; goto again; } /* store input protocol */ fprintf(server, "filename: %s\n", filename); for (cp = mode; *cp; cp++) if(ISUPPER(*cp)) *cp = (char)tolower((int)*cp); /* store input protocol */ fprintf(server, "mode: %s\n", mode); fclose(server); for (pf = formata; 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 == opcode_WRQ) recvtftp(test, pf); else sendtftp(test, pf); return 0; } /* * Validate file access. */ static int validate_access(struct testcase *test, const char *filename, int mode) { char *ptr; long testno, partno; int error; char partbuf[80]="data"; logmsg("trying to get file: %s mode %x", filename, mode); if(!strncmp("verifiedserver", filename, 14)) { char weare[128]; size_t count = sprintf(weare, "WE ROOLZ: %ld\r\n", (long)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(*ptr)) ptr++; /* get the number */ testno = strtol(ptr, &ptr, 10); if(testno > 10000) { partno = testno % 10000; testno /= 10000; } else partno = 0; logmsg("requested test number %ld part %ld", testno, partno); test->num = testno; file = test2file(testno); if(0 != partno) sprintf(partbuf, "data%ld", partno); if(file) { FILE *stream=fopen(file, "rb"); if(!stream) { error = ERRNO; logmsg("fopen() failed with error: %d %s", error, strerror(error)); logmsg("Error opening file: %s", file); logmsg("Couldn't open test file: %s", file); return EACCESS; } else { size_t count; test->buffer = (char *)spitout(stream, "reply", partbuf, &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; } static int timeout; #ifdef HAVE_SIGSETJMP static sigjmp_buf timeoutbuf; #endif static void timer(int signum) { (void)signum; logmsg("alarm!"); timeout += rexmtval; if(timeout >= maxtimeout) { clear_advisor_read_lock(SERVERLOGS_LOCK); exit(1); } #ifdef HAVE_SIGSETJMP siglongjmp(timeoutbuf, 1); #endif } static unsigned short sendblock; static struct tftphdr *sdp; static struct tftphdr *sap; /* ack packet */ /* * Send the requested file. */ static void sendtftp(struct testcase *test, struct formats *pf) { int size; ssize_t n; sendblock = 1; #if defined(HAVE_ALARM) && defined(SIGALRM) mysignal(SIGALRM, timer); #endif sdp = r_init(); sap = (struct tftphdr *)ackbuf; do { size = readit(test, &sdp, pf->f_convert); if (size < 0) { nak(ERRNO + 100); return; } sdp->th_opcode = htons((u_short)opcode_DATA); sdp->th_block = htons((u_short)sendblock); timeout = 0; #ifdef HAVE_SIGSETJMP (void) sigsetjmp(timeoutbuf, 1); #endif send_data: if (swrite(peer, sdp, size + 4) != size + 4) { logmsg("write\n"); return; } read_ahead(test, pf->f_convert); for ( ; ; ) { #ifdef HAVE_ALARM alarm(rexmtval); /* read the ack */ #endif n = sread(peer, ackbuf, sizeof (ackbuf)); #ifdef HAVE_ALARM alarm(0); #endif if (n < 0) { logmsg("read: fail\n"); return; } sap->th_opcode = ntohs((u_short)sap->th_opcode); sap->th_block = ntohs((u_short)sap->th_block); if (sap->th_opcode == opcode_ERROR) { logmsg("got ERROR"); return; } if (sap->th_opcode == opcode_ACK) { if (sap->th_block == sendblock) { break; } /* Re-synchronize with the other side */ (void) synchnet(peer); if (sap->th_block == (sendblock-1)) { goto send_data; } } } sendblock++; } while (size == SEGSIZE); } static void justtimeout(int signum) { (void)signum; } static unsigned short recvblock; static struct tftphdr *rdp; static struct tftphdr *rap; /* ack buffer */ /* * Receive a file. */ static void recvtftp(struct testcase *test, struct formats *pf) { ssize_t n, size; recvblock = 0; #if defined(HAVE_ALARM) && defined(SIGALRM) mysignal(SIGALRM, timer); #endif rdp = w_init(); rap = (struct tftphdr *)ackbuf; do { timeout = 0; rap->th_opcode = htons((u_short)opcode_ACK); rap->th_block = htons((u_short)recvblock); recvblock++; #ifdef HAVE_SIGSETJMP (void) sigsetjmp(timeoutbuf, 1); #endif send_ack: if (swrite(peer, ackbuf, 4) != 4) { logmsg("write: fail\n"); goto abort; } write_behind(test, pf->f_convert); for ( ; ; ) { #ifdef HAVE_ALARM alarm(rexmtval); #endif n = sread(peer, rdp, PKTSIZE); #ifdef HAVE_ALARM alarm(0); #endif if (n < 0) { /* really? */ logmsg("read: fail\n"); goto abort; } rdp->th_opcode = ntohs((u_short)rdp->th_opcode); rdp->th_block = ntohs((u_short)rdp->th_block); if (rdp->th_opcode == opcode_ERROR) goto abort; if (rdp->th_opcode == opcode_DATA) { if (rdp->th_block == recvblock) { break; /* normal */ } /* Re-synchronize with the other side */ (void) synchnet(peer); if (rdp->th_block == (recvblock-1)) goto send_ack; /* rexmit */ } } size = writeit(test, &rdp, (int)(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); rap->th_opcode = htons((u_short)opcode_ACK); /* send the "final" ack */ rap->th_block = htons((u_short)recvblock); (void) swrite(peer, ackbuf, 4); #if defined(HAVE_ALARM) && defined(SIGALRM) mysignal(SIGALRM, justtimeout); /* just abort read on timeout */ alarm(rexmtval); #endif n = sread(peer, buf, sizeof(buf)); /* normally times out and quits */ #ifdef HAVE_ALARM alarm(0); #endif if (n >= 4 && /* if read some data */ rdp->th_opcode == opcode_DATA && /* and got a data block */ recvblock == rdp->th_block) { /* then my last ack was lost */ (void) swrite(peer, ackbuf, 4); /* resend final ack */ } abort: return; } struct errmsg { int e_code; const char *e_msg; }; static struct errmsg 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)opcode_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 = (int)strlen(pe->e_msg); tp->th_msg[length] = '\0'; length += 5; if (swrite(peer, buf, length) != length) logmsg("nak: fail\n"); }