/* * Send a file via the TFTP data session. */ void tftp_send(int peer, uint16_t *block, struct tftp_stats *ts) { struct tftphdr *rp; int size, n_data, n_ack, try; uint16_t oldblock; char sendbuffer[MAXPKTSIZE]; char recvbuffer[MAXPKTSIZE]; rp = (struct tftphdr *)recvbuffer; *block = 1; ts->amount = 0; do { if (debug&DEBUG_SIMPLE) tftp_log(LOG_DEBUG, "Sending block %d", *block); size = read_file(sendbuffer, segsize); if (size < 0) { tftp_log(LOG_ERR, "read_file returned %d", size); send_error(peer, errno + 100); goto abort; } for (try = 0; ; try++) { n_data = send_data(peer, *block, sendbuffer, size); if (n_data > 0) { if (try == maxtimeouts) { tftp_log(LOG_ERR, "Cannot send DATA packet #%d, " "giving up", *block); return; } tftp_log(LOG_ERR, "Cannot send DATA packet #%d, trying again", *block); continue; } n_ack = receive_packet(peer, recvbuffer, MAXPKTSIZE, NULL, timeoutpacket); if (n_ack < 0) { if (n_ack == RP_TIMEOUT) { if (try == maxtimeouts) { tftp_log(LOG_ERR, "Timeout #%d send ACK %d " "giving up", try, *block); return; } tftp_log(LOG_WARNING, "Timeout #%d on ACK %d", try, *block); continue; } /* Either read failure or ERROR packet */ if (debug&DEBUG_SIMPLE) tftp_log(LOG_ERR, "Aborting: %s", rp_strerror(n_ack)); goto abort; } if (rp->th_opcode == ACK) { ts->blocks++; if (rp->th_block == *block) { ts->amount += size; break; } /* Re-synchronize with the other side */ (void) synchnet(peer); if (rp->th_block == (*block - 1)) { ts->retries++; continue; } } } oldblock = *block; (*block)++; if (oldblock > *block) { if (options[OPT_ROLLOVER].o_request == NULL) { /* * "rollover" option not specified in * tftp client. Default to rolling block * counter to 0. */ *block = 0; } else { *block = atoi(options[OPT_ROLLOVER].o_request); } ts->rollovers++; } gettimeofday(&(ts->tstop), NULL); } while (size == segsize); abort: return; } /* * Receive a file via the TFTP data session. * * - It could be that the first block has already arrived while * trying to figure out if we were receiving options or not. In * that case it is passed to this function. */ void tftp_receive(int peer, uint16_t *block, struct tftp_stats *ts, struct tftphdr *firstblock, size_t fb_size) { struct tftphdr *rp; uint16_t oldblock; int n_data, n_ack, writesize, i, retry; char recvbuffer[MAXPKTSIZE]; ts->amount = 0; if (firstblock != NULL) { writesize = write_file(firstblock->th_data, fb_size); ts->amount += writesize; for (i = 0; ; i++) { n_ack = send_ack(peer, *block); if (n_ack > 0) { if (i == maxtimeouts) { tftp_log(LOG_ERR, "Cannot send ACK packet #%d, " "giving up", *block); return; } tftp_log(LOG_ERR, "Cannot send ACK packet #%d, trying again", *block); continue; } break; } if (fb_size != segsize) { gettimeofday(&(ts->tstop), NULL); return; } } rp = (struct tftphdr *)recvbuffer; do { oldblock = *block; (*block)++; if (oldblock > *block) { if (options[OPT_ROLLOVER].o_request == NULL) { /* * "rollover" option not specified in * tftp client. Default to rolling block * counter to 0. */ *block = 0; } else { *block = atoi(options[OPT_ROLLOVER].o_request); } ts->rollovers++; } for (retry = 0; ; retry++) { if (debug&DEBUG_SIMPLE) tftp_log(LOG_DEBUG, "Receiving DATA block %d", *block); n_data = receive_packet(peer, recvbuffer, MAXPKTSIZE, NULL, timeoutpacket); if (n_data < 0) { if (retry == maxtimeouts) { tftp_log(LOG_ERR, "Timeout #%d on DATA block %d, " "giving up", retry, *block); return; } if (n_data == RP_TIMEOUT) { tftp_log(LOG_WARNING, "Timeout #%d on DATA block %d", retry, *block); send_ack(peer, oldblock); continue; } /* Either read failure or ERROR packet */ if (debug&DEBUG_SIMPLE) tftp_log(LOG_DEBUG, "Aborting: %s", rp_strerror(n_data)); goto abort; } if (rp->th_opcode == DATA) { ts->blocks++; if (rp->th_block == *block) break; tftp_log(LOG_WARNING, "Expected DATA block %d, got block %d", *block, rp->th_block); /* Re-synchronize with the other side */ (void) synchnet(peer); if (rp->th_block == (*block-1)) { tftp_log(LOG_INFO, "Trying to sync"); *block = oldblock; ts->retries++; goto send_ack; /* rexmit */ } } else { tftp_log(LOG_WARNING, "Expected DATA block, got %s block", packettype(rp->th_opcode)); } } if (n_data > 0) { writesize = write_file(rp->th_data, n_data); ts->amount += writesize; if (writesize <= 0) { tftp_log(LOG_ERR, "write_file returned %d", writesize); if (writesize < 0) send_error(peer, errno + 100); else send_error(peer, ENOSPACE); goto abort; } } send_ack: for (i = 0; ; i++) { n_ack = send_ack(peer, *block); if (n_ack > 0) { if (i == maxtimeouts) { tftp_log(LOG_ERR, "Cannot send ACK packet #%d, " "giving up", *block); return; } tftp_log(LOG_ERR, "Cannot send ACK packet #%d, trying again", *block); continue; } break; } gettimeofday(&(ts->tstop), NULL); } while (n_data == segsize); /* Don't do late packet management for the client implementation */ if (acting_as_client) return; for (i = 0; ; i++) { n_data = receive_packet(peer, (char *)rp, pktsize, NULL, timeoutpacket); if (n_data <= 0) break; if (n_data > 0 && rp->th_opcode == DATA && /* and got a data block */ *block == rp->th_block) /* then my last ack was lost */ send_ack(peer, *block); /* resend final ack */ } abort: return; }
/* * RRQ - send a file to the client */ void tftp_rrq(int peer, char *recvbuffer, ssize_t size) { char *cp; int has_options = 0, ecode; char *filename, *mode; char fnbuf[PATH_MAX]; cp = parse_header(peer, recvbuffer, size, &filename, &mode); size -= (cp - recvbuffer) + 1; strcpy(fnbuf, filename); reduce_path(fnbuf); filename = fnbuf; if (size > 0) { if (options_rfc_enabled) has_options = !parse_options(peer, cp, size); else tftp_log(LOG_INFO, "Options found but not enabled"); } ecode = validate_access(peer, &filename, RRQ); if (ecode == 0) { if (has_options) { int n; char lrecvbuffer[MAXPKTSIZE]; struct tftphdr *rp = (struct tftphdr *)lrecvbuffer; send_oack(peer); n = receive_packet(peer, lrecvbuffer, MAXPKTSIZE, NULL, timeoutpacket); if (n < 0) { if (debug&DEBUG_SIMPLE) tftp_log(LOG_DEBUG, "Aborting: %s", rp_strerror(n)); return; } if (rp->th_opcode != ACK) { if (debug&DEBUG_SIMPLE) tftp_log(LOG_DEBUG, "Expected ACK, got %s on OACK", packettype(rp->th_opcode)); return; } } } if (logging) tftp_log(LOG_INFO, "%s: read request for %s: %s", peername, filename, errtomsg(ecode)); if (ecode) { /* * Avoid storms of naks to a RRQ broadcast for a relative * bootfile pathname from a diskless Sun. */ if (suppress_naks && *filename != '/' && ecode == ENOTFOUND) exit(0); send_error(peer, ecode); exit(1); } tftp_xmitfile(peer, mode); }