/* $OpenBSD: tftp.c,v 1.22 2009/10/27 23:59:44 deraadt Exp $ */ /* $NetBSD: tftp.c,v 1.5 1995/04/29 05:55:25 cgd Exp $ */ /* * Copyright (c) 1983, 1993 * 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. * 3. 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. */ /* * TFTP User Program -- Protocol Machines * * This version includes many modifications by Jim Guyton */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "extern.h" #include "tftpsubs.h" static int makerequest(int, const char *, struct tftphdr *, const char *); static void nak(int); static void tpacket(const char *, struct tftphdr *, int); static void startclock(void); static void stopclock(void); static void printstats(const char *, unsigned long); static void printtimeout(void); static void oack(struct tftphdr *, int, int); static int oack_set(const char *, const char *); extern struct sockaddr_in peeraddr; /* filled in by main */ extern int f; /* the opened socket */ extern int trace; extern int verbose; extern int rexmtval; extern int maxtimeout; extern FILE *file; extern volatile sig_atomic_t intrflag; extern char *ackbuf; extern int has_options; extern int opt_tsize; extern int opt_tout; extern int opt_blksize; struct timeval tstart; struct timeval tstop; unsigned int segment_size = SEGSIZE; unsigned int packet_size = SEGSIZE + 4; struct errmsg { int e_code; 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" }, { EOPTNEG, "Option negotiation failed" }, { -1, NULL } }; struct options { const char *o_type; } options[] = { { "tsize" }, { "timeout" }, { "blksize" }, { NULL } }; enum opt_enum { OPT_TSIZE = 0, OPT_TIMEOUT, OPT_BLKSIZE }; /* * Send the requested file. */ void sendfile(int fd, char *name, char *mode) { struct tftphdr *dp, *ap; /* data and ack packets */ struct sockaddr_in from; struct pollfd pfd[1]; unsigned long amount; socklen_t fromlen; int convert; /* true if converting crlf -> lf */ int n, nfds, error, timeouts, block, size; startclock(); /* start stat's clock */ dp = r_init(); /* reset fillbuf/read-ahead code */ ap = (struct tftphdr *)ackbuf; file = fdopen(fd, "r"); convert = !strcmp(mode, "netascii"); block = 0; amount = 0; do { /* read data from file */ if (!block) size = makerequest(WRQ, name, dp, mode) - 4; else { size = readit(file, &dp, convert, segment_size); if (size < 0) { nak(errno + 100); break; } dp->th_opcode = htons((u_short)DATA); dp->th_block = htons((u_short)block); } /* send data to server and wait for server ACK */ for (timeouts = 0, error = 0; !intrflag;) { if (timeouts >= maxtimeout) { printtimeout(); goto abort; } if (!error) { if (trace) tpacket("sent", dp, size + 4); if (sendto(f, dp, size + 4, 0, (struct sockaddr *)&peeraddr, sizeof(peeraddr)) != size + 4) { warn("sendto"); goto abort; } if (block > 0) read_ahead(file, convert, segment_size); } error = 0; pfd[0].fd = f; pfd[0].events = POLLIN; nfds = poll(pfd, 1, rexmtval * 1000); if (nfds == 0) { timeouts += rexmtval; continue; } if (nfds == -1) { error = 1; if (errno == EINTR) continue; warn("poll"); goto abort; } fromlen = sizeof(from); n = recvfrom(f, ackbuf, packet_size, 0, (struct sockaddr *)&from, &fromlen); if (n == 0) { warn("recvfrom"); goto abort; } if (n == -1) { error = 1; if (errno == EINTR) continue; warn("recvfrom"); goto abort; } peeraddr.sin_port = from.sin_port; /* added */ if (trace) tpacket("received", ap, n); ap->th_opcode = ntohs(ap->th_opcode); if (ap->th_opcode == OACK) { oack(ap, n, 0); break; } ap->th_block = ntohs(ap->th_block); if (ap->th_opcode == ERROR) { printf("Error code %d: %s\n", ap->th_code, ap->th_msg); goto abort; } if (ap->th_opcode == ACK) { int j; if (ap->th_block == block) break; /* re-synchronize with other side */ j = synchnet(f); if (j && trace) printf("discarded %d packets\n", j); if (ap->th_block == (block - 1)) continue; } error = 1; /* received packet does not match */ } if (block > 0) amount += size; block++; } while ((size == segment_size || block == 1) && !intrflag); abort: fclose(file); stopclock(); if (amount > 0) { if (intrflag) putchar('\n'); printstats("Sent", amount); } } /* * Receive a file. */ void recvfile(int fd, char *name, char *mode) { struct tftphdr *dp, *ap; /* data and ack packets */ struct sockaddr_in from; struct pollfd pfd[1]; unsigned long amount; socklen_t fromlen; int convert; /* true if converting crlf -> lf */ int n, nfds, error, timeouts, block, size; int firsttrip; startclock(); /* start stat's clock */ dp = w_init(); /* reset fillbuf/read-ahead code */ ap = (struct tftphdr *)ackbuf; file = fdopen(fd, "w"); convert = !strcmp(mode, "netascii"); n = 0; block = 1; amount = 0; firsttrip = 1; options: do { /* create new ACK packet */ if (firsttrip) { size = makerequest(RRQ, name, ap, mode); firsttrip = 0; } else { ap->th_opcode = htons((u_short)ACK); ap->th_block = htons((u_short)(block)); size = 4; block++; } /* send ACK to server and wait for server data */ for (timeouts = 0, error = 0; !intrflag;) { if (timeouts >= maxtimeout) { printtimeout(); goto abort; } if (!error) { if (trace) tpacket("sent", ap, size); if (sendto(f, ackbuf, size, 0, (struct sockaddr *)&peeraddr, sizeof(peeraddr)) != size) { warn("sendto"); goto abort; } write_behind(file, convert); } error = 0; pfd[0].fd = f; pfd[0].events = POLLIN; nfds = poll(pfd, 1, rexmtval * 1000); if (nfds == 0) { timeouts += rexmtval; continue; } if (nfds == -1) { error = 1; if (errno == EINTR) continue; warn("poll"); goto abort; } fromlen = sizeof(from); n = recvfrom(f, dp, packet_size, 0, (struct sockaddr *)&from, &fromlen); if (n == 0) { warn("recvfrom"); goto abort; } if (n == -1) { error = 1; if (errno == EINTR) continue; warn("recvfrom"); goto abort; } peeraddr.sin_port = from.sin_port; /* added */ if (trace) tpacket("received", dp, n); dp->th_opcode = ntohs(dp->th_opcode); if (dp->th_opcode == OACK) { oack(dp, n, 0); block = 0; goto options; } dp->th_block = ntohs(dp->th_block); if (dp->th_opcode == ERROR) { printf("Error code %d: %s\n", dp->th_code, dp->th_msg); goto abort; } if (dp->th_opcode == DATA) { int j; if (dp->th_block == block) break; /* re-synchronize with other side */ j = synchnet(f); if (j && trace) printf("discarded %d packets\n", j); if (dp->th_block == (block - 1)) continue; } error = 1; /* received packet does not match */ } /* write data to file */ size = writeit(file, &dp, n - 4, convert); if (size < 0) { nak(errno + 100); break; } amount += size; } while (size == segment_size && !intrflag); abort: /* ok to ack, since user has seen err msg */ ap->th_opcode = htons((u_short)ACK); ap->th_block = htons((u_short)block); (void)sendto(f, ackbuf, 4, 0, (struct sockaddr *)&peeraddr, sizeof(peeraddr)); write_behind(file, convert); /* flush last buffer */ fclose(file); stopclock(); if (amount > 0) { if (intrflag) putchar('\n'); printstats("Received", amount); } } static int makerequest(int request, const char *name, struct tftphdr *tp, const char *mode) { char *cp; int len, pktlen; off_t fsize = 0; struct stat st; tp->th_opcode = htons((u_short)request); cp = tp->th_stuff; pktlen = packet_size - offsetof(struct tftphdr, th_stuff); len = strlen(name) + 1; strlcpy(cp, name, pktlen); strlcpy(cp + len, mode, pktlen - len); len += strlen(mode) + 1; if (opt_tsize) { if (request == WRQ) { stat(name, &st); fsize = st.st_size; } len += snprintf(cp + len, pktlen - len, "%s%c%lld%c", options[OPT_TSIZE].o_type, 0, fsize, 0); } if (opt_tout) len += snprintf(cp + len, pktlen - len, "%s%c%d%c", options[OPT_TIMEOUT].o_type, 0, rexmtval, 0); if (opt_blksize) len += snprintf(cp + len, pktlen - len, "%s%c%d%c", options[OPT_BLKSIZE].o_type, 0, opt_blksize, 0); return (cp + len - (char *)tp); } /* * 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 errmsg *pe; struct tftphdr *tp; int length; tp = (struct tftphdr *)ackbuf; 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; } length = strlcpy(tp->th_msg, pe->e_msg, packet_size) + 5; if (length > packet_size) length = packet_size; if (trace) tpacket("sent", tp, length); if (sendto(f, ackbuf, length, 0, (struct sockaddr *)&peeraddr, sizeof(peeraddr)) != length) warn("nak"); } static void tpacket(const char *s, struct tftphdr *tp, int n) { char *cp, *file; static char *opcodes[] = { "#0", "RRQ", "WRQ", "DATA", "ACK", "ERROR", "OACK" }; u_short op = ntohs(tp->th_opcode); if (op < RRQ || op > OACK) printf("%s opcode=%x ", s, op); else printf("%s %s ", s, opcodes[op]); switch (op) { case RRQ: case WRQ: n -= 2; file = cp = tp->th_stuff; cp = strchr(cp, '\0'); printf("\n"); break; case DATA: printf("\n", ntohs(tp->th_block), n - 4); break; case ACK: printf("\n", ntohs(tp->th_block)); break; case ERROR: printf("\n", ntohs(tp->th_code), tp->th_msg); break; case OACK: printf("<"); oack(tp, n, 1); printf(">\n"); break; } } static void startclock(void) { (void)gettimeofday(&tstart, NULL); } static void stopclock(void) { (void)gettimeofday(&tstop, NULL); } static void printstats(const char *direction, unsigned long amount) { double delta; /* compute delta in 1/10's second units */ delta = ((tstop.tv_sec * 10.) + (tstop.tv_usec / 100000)) - ((tstart.tv_sec * 10.) + (tstart.tv_usec / 100000)); delta = delta / 10.; /* back to seconds */ printf("%s %lu bytes in %.1f seconds", direction, amount, delta); if (verbose) printf(" [%.0f bits/sec]", (amount * 8.) / delta); putchar('\n'); } static void printtimeout(void) { printf("Transfer timed out.\n"); } static void oack(struct tftphdr *tp, int size, int trace) { int i, len, off; char *opt, *val; u_short op = ntohs(tp->th_opcode); opt = tp->th_u.tu_stuff; val = tp->th_u.tu_stuff; if (op == RRQ || op == WRQ) { len = strlen(opt) + 1; opt = strchr(opt, '\0'); opt++; len += strlen(opt) + 1; opt = strchr(opt, '\0'); opt++; val = opt; off = len; if (trace) printf(", "); } else off = 2; for (i = off, len = 0; i < size - 1; i++) { if (*val != '\0') { val++; continue; } /* got option and value */ val++; if (trace) printf("%s=%s", opt, val); else if (oack_set(opt, val) == -1) break; len = strlen(val) + 1; val += len; opt = val; i += len; if (trace && i < size - 1) printf(", "); } } int oack_set(const char *option, const char *value) { int i, n; const char *errstr; for (i = 0; options[i].o_type != NULL; i++) { if (!strcasecmp(options[i].o_type, option)) { if (i == OPT_TSIZE) { /* XXX verify OACK response */ } if (i == OPT_TIMEOUT) { /* verify OACK response */ n = strtonum(value, TIMEOUT_MIN, TIMEOUT_MAX, &errstr); if (errstr || rexmtval != n || opt_tout == 0) { nak(EOPTNEG); intrflag = 1; return (-1); } /* OK */ } if (i == OPT_BLKSIZE) { /* verify OACK response */ n = strtonum(value, SEGSIZE_MIN, SEGSIZE_MAX, &errstr); if (errstr || opt_blksize != n || opt_blksize == 0) { nak(EOPTNEG); intrflag = 1; return (-1); } /* OK, set option */ segment_size = n; packet_size = segment_size + 4; } } } return (1); }