/**************************************************************************** * apps/netutils/tftpc/tftpc_get.c * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance with the * License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include #include "netutils/tftp.h" #include "tftpc_internal.h" #if defined(CONFIG_NET) && defined(CONFIG_NET_UDP) /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #define TFTP_RETRIES 3 /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: tftp_parsedatapacket ****************************************************************************/ static inline int tftp_parsedatapacket(FAR const uint8_t *packet, FAR uint16_t *opcode, FAR uint16_t *blockno) { *opcode = (uint16_t)packet[0] << 8 | (uint16_t)packet[1]; if (*opcode == TFTP_DATA) { *blockno = (uint16_t)packet[2] << 8 | (uint16_t)packet[3]; return OK; } #ifdef CONFIG_DEBUG_NET_WARN else if (*opcode == TFTP_ERR) { tftp_parseerrpacket(packet); } #endif return ERROR; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: tftpget_cb * * Input Parameters: * remote - The name of the file on the TFTP server. * addr - The IP address of the server in network order * binary - TRUE: Perform binary ('octet') transfer * FALSE: Perform text ('netascii') transfer * cb - callback that will be called with data packets * ctx - pointer passed to the previous callback * ****************************************************************************/ int tftpget_cb(FAR const char *remote, in_addr_t addr, bool binary, tftp_callback_t tftp_cb, FAR void *ctx) { struct sockaddr_in server; /* The address of the TFTP server */ struct sockaddr_in from; /* The address the last UDP message recv'd from */ FAR uint8_t *packet; /* Allocated memory to hold one packet */ uint16_t blockno = 0; /* The current transfer block number */ uint16_t opcode; /* Received opcode */ uint16_t rblockno; /* Received block number */ int len; /* Generic length */ int sd; /* Socket descriptor for socket I/O */ int retry; /* Retry counter */ int nbytesrecvd = 0; /* The number of bytes received in the packet */ int ndatabytes; /* The number of data bytes received */ int result = ERROR; /* Assume failure */ int ret; /* Generic return status */ /* Allocate the buffer to used for socket/disk I/O */ packet = (FAR uint8_t *)zalloc(TFTP_IOBUFSIZE); if (!packet) { nerr("ERROR: packet memory allocation failure\n"); errno = ENOMEM; return result; } /* Initialize a UDP socket and setup the server address */ sd = tftp_sockinit(&server, addr); if (sd < 0) { goto errout; } /* Then enter the transfer loop. Loop until the entire file has * been received or until an error occurs. */ do { /* Increment the TFTP block number for the next transfer */ blockno++; /* Send the next block if the file within a loop. We will * retry up to TFTP_RETRIES times before giving up on the * transfer. */ for (retry = 0; retry < TFTP_RETRIES; retry++) { /* Send the read request using the well-known port number before * receiving the first block. Each retry of the first block will * re-send the request. */ if (blockno == 1) { len = tftp_mkreqpacket(packet, TFTP_RRQ, remote, binary); server.sin_port = HTONS(CONFIG_NETUTILS_TFTP_PORT); ret = tftp_sendto(sd, packet, len, &server); if (ret != len) { goto errout_with_sd; } /* Subsequent sendto will use the port number selected by the * TFTP server in the DATA packet. Setting the server port to * zero here indicates that we have not yet received the server * port number. */ server.sin_port = 0; } /* Get the next packet from the server */ nbytesrecvd = tftp_recvfrom(sd, packet, TFTP_IOBUFSIZE, &from); /* Check if anything valid was received */ if (nbytesrecvd > 0) { /* Verify the sender address and port number */ if (server.sin_addr.s_addr != from.sin_addr.s_addr) { ninfo("Invalid address in DATA\n"); retry--; continue; } if (server.sin_port && server.sin_port != from.sin_port) { ninfo("Invalid port in DATA\n"); len = tftp_mkerrpacket(packet, TFTP_ERR_UNKID, TFTP_ERRST_UNKID); ret = tftp_sendto(sd, packet, len, &from); retry--; continue; } /* Parse the incoming DATA packet */ if (nbytesrecvd < TFTP_DATAHEADERSIZE) { /* Packet is not big enough to be parsed */ ninfo("Tiny data packet ignored\n"); continue; } if (tftp_parsedatapacket(packet, &opcode, &rblockno) != OK || blockno != rblockno) { /* Opcode is not TFTP_DATA or the block number is * unexpected. */ ninfo("Parse failure\n"); if (opcode > TFTP_MAXRFC1350) { len = tftp_mkerrpacket(packet, TFTP_ERR_ILLEGALOP, TFTP_ERRST_ILLEGALOP); ret = tftp_sendto(sd, packet, len, &from); } continue; } /* Replace the server port to the one in the good response */ if (!server.sin_port) { server.sin_port = from.sin_port; } /* Then break out of the loop */ break; } } /* Did we exhaust all of the retries? */ if (retry == TFTP_RETRIES) { ninfo("Retry limit exceeded\n"); goto errout_with_sd; } /* Write the received data chunk to the file */ ndatabytes = nbytesrecvd - TFTP_DATAHEADERSIZE; tftp_dumpbuffer("Recvd DATA", packet + TFTP_DATAHEADERSIZE, ndatabytes); if (tftp_cb(ctx, 0, packet + TFTP_DATAHEADERSIZE, ndatabytes) < 0) { goto errout_with_sd; } /* Send the acknowledgment */ len = tftp_mkackpacket(packet, blockno); ret = tftp_sendto(sd, packet, len, &server); if (ret != len) { goto errout_with_sd; } ninfo("ACK blockno %d\n", blockno); } while (ndatabytes >= TFTP_DATASIZE); /* Return success */ result = OK; errout_with_sd: close(sd); errout: free(packet); return result; } /**************************************************************************** * Name: tftp_write ****************************************************************************/ static ssize_t tftp_write(FAR void *ctx, uint32_t offset, FAR uint8_t *buf, size_t len) { int fd = (intptr_t)ctx; size_t left = len; ssize_t nbyteswritten; while (left > 0) { /* Write the data... repeating the write in the event that it was * interrupted by a signal. */ do { nbyteswritten = write(fd, buf, left); } while (nbyteswritten < 0 && errno == EINTR); /* Check for non-EINTR errors */ if (nbyteswritten < 0) { nerr("ERROR: write failed: %d\n", errno); return ERROR; } /* Handle partial writes */ ninfo("Wrote %zd bytes to file\n", nbyteswritten); left -= nbyteswritten; buf += nbyteswritten; } return len; } /**************************************************************************** * Name: tftpget * * Input Parameters: * remote - The name of the file on the TFTP server. * local - Path to the location on a mounted filesystem where the file * will be stored. * addr - The IP address of the server in network order * binary - TRUE: Perform binary ('octect') transfer * FALSE: Perform text ('netascii') transfer * ****************************************************************************/ int tftpget(FAR const char *remote, FAR const char *local, in_addr_t addr, bool binary) { int fd; /* File descriptor for file I/O */ int result = ERROR; /* Generic return status */ /* Open the file for writing */ fd = open(local, O_WRONLY | O_CREAT | O_TRUNC, 0666); if (fd < 0) { nerr("ERROR: open failed: %d\n", errno); goto errout; } result = tftpget_cb(remote, addr, binary, tftp_write, (FAR void *)(intptr_t)fd); close(fd); errout: return result; } #endif /* CONFIG_NET && CONFIG_NET_UDP */