diff --git a/src/apps/tftp/tftp_server.c b/src/apps/tftp/tftp_server.c index 4c0bbe15..e5c5e887 100644 --- a/src/apps/tftp/tftp_server.c +++ b/src/apps/tftp/tftp_server.c @@ -1,417 +1,417 @@ -/******************************************************************* - * - * @file tftp_server.c - * - * @author Logan Gunthorpe - * Dirk Ziegelmeier - * - * @brief Trivial File Transfer Protocol (RFC 1350) - * - * Copyright (c) Deltatee Enterprises Ltd. 2013 - * 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. The name of the author may not be used to endorse or promote products - * derived from this software without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. - * - * Author: Logan Gunthorpe - * Dirk Ziegelmeier - * - */ - -/** - * @defgroup tftp TFTP server - * @ingroup apps - * - * This is simple TFTP server for the lwIP raw API. - */ - -#include "lwip/apps/tftp_server.h" - -#if LWIP_UDP - -#include "lwip/udp.h" -#include "lwip/timeouts.h" -#include "lwip/debug.h" - -#define TFTP_MAX_PAYLOAD_SIZE 512 -#define TFTP_HEADER_LENGTH 4 - -#define TFTP_RRQ 1 -#define TFTP_WRQ 2 -#define TFTP_DATA 3 -#define TFTP_ACK 4 -#define TFTP_ERROR 5 - -enum tftp_error { - TFTP_ERROR_FILE_NOT_FOUND = 1, - TFTP_ERROR_ACCESS_VIOLATION = 2, - TFTP_ERROR_DISK_FULL = 3, - TFTP_ERROR_ILLEGAL_OPERATION = 4, - TFTP_ERROR_UNKNOWN_TRFR_ID = 5, - TFTP_ERROR_FILE_EXISTS = 6, - TFTP_ERROR_NO_SUCH_USER = 7 -}; - -#include - -struct tftp_state { - const struct tftp_context *ctx; - void *handle; - struct pbuf *last_data; - struct udp_pcb *upcb; - ip_addr_t addr; - u16_t port; - int timer; - int last_pkt; - u16_t blknum; - u8_t retries; - u8_t mode_write; -}; - -static struct tftp_state tftp_state; - -static void tftp_tmr(void* arg); - -static void -close_handle(void) -{ - tftp_state.port = 0; - ip_addr_set_any(0, &tftp_state.addr); - - if(tftp_state.last_data != NULL) { - pbuf_free(tftp_state.last_data); - tftp_state.last_data = NULL; - } - - sys_untimeout(tftp_tmr, NULL); - - if (tftp_state.handle) { - tftp_state.ctx->close(tftp_state.handle); - tftp_state.handle = NULL; - LWIP_DEBUGF(TFTP_DEBUG | LWIP_DBG_STATE, ("tftp: closing\n")); - } -} - -static void -send_error(const ip_addr_t *addr, u16_t port, enum tftp_error code, const char *str) -{ - int str_length = strlen(str); - struct pbuf* p; - u16_t* payload; - - p = pbuf_alloc(PBUF_TRANSPORT, (u16_t)(TFTP_HEADER_LENGTH + str_length + 1), PBUF_RAM); - if(p == NULL) { - return; - } - - payload = (u16_t*) p->payload; - payload[0] = PP_HTONS(TFTP_ERROR); - payload[1] = lwip_htons(code); - MEMCPY(&payload[2], str, str_length + 1); - - udp_sendto(tftp_state.upcb, p, addr, port); - pbuf_free(p); -} - -static void -send_ack(u16_t blknum) -{ - struct pbuf* p; - u16_t* payload; - - p = pbuf_alloc(PBUF_TRANSPORT, TFTP_HEADER_LENGTH, PBUF_RAM); - if(p == NULL) { - return; - } - payload = (u16_t*) p->payload; - - payload[0] = PP_HTONS(TFTP_ACK); - payload[1] = lwip_htons(blknum); - udp_sendto(tftp_state.upcb, p, &tftp_state.addr, tftp_state.port); - pbuf_free(p); -} - -static void -resend_data(void) -{ - struct pbuf *p = pbuf_alloc(PBUF_TRANSPORT, tftp_state.last_data->len, PBUF_RAM); - if(p == NULL) { - return; - } - - if(pbuf_copy(p, tftp_state.last_data) != ERR_OK) { - pbuf_free(p); - return; - } - - udp_sendto(tftp_state.upcb, p, &tftp_state.addr, tftp_state.port); - pbuf_free(p); -} - -static void -send_data(void) -{ - u16_t *payload; - int ret; - - if(tftp_state.last_data != NULL) { - pbuf_free(tftp_state.last_data); - } - - tftp_state.last_data = pbuf_alloc(PBUF_TRANSPORT, TFTP_HEADER_LENGTH + TFTP_MAX_PAYLOAD_SIZE, PBUF_RAM); - if(tftp_state.last_data == NULL) { - return; - } - - payload = (u16_t *) tftp_state.last_data->payload; - payload[0] = PP_HTONS(TFTP_DATA); - payload[1] = lwip_htons(tftp_state.blknum); - - ret = tftp_state.ctx->read(tftp_state.handle, &payload[2], TFTP_MAX_PAYLOAD_SIZE); - if (ret < 0) { - send_error(&tftp_state.addr, tftp_state.port, TFTP_ERROR_ACCESS_VIOLATION, "Error occured while reading the file."); - close_handle(); - return; - } - - pbuf_realloc(tftp_state.last_data, (u16_t)(TFTP_HEADER_LENGTH + ret)); - resend_data(); -} - -static void -recv(void *arg, struct udp_pcb *upcb, struct pbuf *p, const ip_addr_t *addr, u16_t port) -{ - u16_t *sbuf = (u16_t *) p->payload; - int opcode; - - LWIP_UNUSED_ARG(arg); - LWIP_UNUSED_ARG(upcb); - - if (((tftp_state.port != 0) && (port != tftp_state.port)) || - (!ip_addr_isany_val(tftp_state.addr) && !ip_addr_cmp(&tftp_state.addr, addr))) { - send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Only one connection at a time is supported"); - pbuf_free(p); - return; - } - - opcode = sbuf[0]; - - tftp_state.last_pkt = tftp_state.timer; - tftp_state.retries = 0; - - switch (opcode) { - case PP_HTONS(TFTP_RRQ): /* fall through */ - case PP_HTONS(TFTP_WRQ): - { - const char tftp_null = 0; - char filename[TFTP_MAX_FILENAME_LEN+1]; - char mode[TFTP_MAX_MODE_LEN+1]; - u16_t filename_end_offset; - u16_t mode_end_offset; - - if(tftp_state.handle != NULL) { - send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Only one connection at a time is supported"); - break; - } - - sys_timeout(TFTP_TIMER_MSECS, tftp_tmr, NULL); - - /* find \0 in pbuf -> end of filename string */ - filename_end_offset = pbuf_memfind(p, &tftp_null, sizeof(tftp_null), 2); - if((u16_t)(filename_end_offset-1) > sizeof(filename)) { - send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Filename too long/not NULL terminated"); - break; - } - pbuf_copy_partial(p, filename, filename_end_offset-1, 2); - - /* find \0 in pbuf -> end of mode string */ - mode_end_offset = pbuf_memfind(p, &tftp_null, sizeof(tftp_null), filename_end_offset+1); - if((u16_t)(mode_end_offset-filename_end_offset) > sizeof(mode)) { - send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Mode too long/not NULL terminated"); - break; - } - pbuf_copy_partial(p, mode, mode_end_offset-filename_end_offset, filename_end_offset+1); - - tftp_state.handle = tftp_state.ctx->open(filename, mode, opcode == PP_HTONS(TFTP_WRQ)); - tftp_state.blknum = 1; - - if (!tftp_state.handle) { - send_error(addr, port, TFTP_ERROR_FILE_NOT_FOUND, "Unable to open requested file."); - break; - } - - LWIP_DEBUGF(TFTP_DEBUG | LWIP_DBG_STATE, ("tftp: %s request from ", (opcode == PP_HTONS(TFTP_WRQ)) ? "write" : "read")); - ip_addr_debug_print(TFTP_DEBUG | LWIP_DBG_STATE, addr); - LWIP_DEBUGF(TFTP_DEBUG | LWIP_DBG_STATE, (" for '%s' mode '%s'\n", filename, mode)); - - ip_addr_copy(tftp_state.addr, *addr); - tftp_state.port = port; - - if (opcode == PP_HTONS(TFTP_WRQ)) { - tftp_state.mode_write = 1; - send_ack(0); - } else { - tftp_state.mode_write = 0; - send_data(); - } - - break; - } - - case PP_HTONS(TFTP_DATA): - { - int ret; - u16_t blknum; - - if (tftp_state.handle == NULL) { - send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "No connection"); - break; - } - - if (tftp_state.mode_write != 1) { - send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Not a write connection"); - break; - } - - blknum = lwip_ntohs(sbuf[1]); - pbuf_header(p, -TFTP_HEADER_LENGTH); - - ret = tftp_state.ctx->write(tftp_state.handle, p); - if (ret < 0) { - send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "error writing file"); - close_handle(); - } else { - send_ack(blknum); - } - - if (p->tot_len < TFTP_MAX_PAYLOAD_SIZE) { - close_handle(); - } - break; - } - - case PP_HTONS(TFTP_ACK): - { - u16_t blknum; - int lastpkt; - - if (tftp_state.handle == NULL) { - send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "No connection"); - break; - } - - if (tftp_state.mode_write != 0) { - send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Not a read connection"); - break; - } - - blknum = lwip_ntohs(sbuf[1]); - if (blknum != tftp_state.blknum) { - send_error(addr, port, TFTP_ERROR_UNKNOWN_TRFR_ID, "Wrong block number"); - break; - } - - lastpkt = 0; - - if (tftp_state.last_data != NULL) { - lastpkt = tftp_state.last_data->tot_len != (TFTP_MAX_PAYLOAD_SIZE + TFTP_HEADER_LENGTH); - } - - if (!lastpkt) { - tftp_state.blknum++; - send_data(); - } else { - close_handle(); - } - - break; - } - - default: - send_error(addr, port, TFTP_ERROR_ILLEGAL_OPERATION, "Unknown operation"); - break; - } - - pbuf_free(p); -} - -static void -tftp_tmr(void* arg) -{ - LWIP_UNUSED_ARG(arg); - - tftp_state.timer++; - - if (tftp_state.handle == NULL) { - return; - } - - sys_timeout(TFTP_TIMER_MSECS, tftp_tmr, NULL); - - if ((tftp_state.timer - tftp_state.last_pkt) > (TFTP_TIMEOUT_MSECS / TFTP_TIMER_MSECS)) { - if ((tftp_state.last_data != NULL) && (tftp_state.retries < TFTP_MAX_RETRIES)) { - LWIP_DEBUGF(TFTP_DEBUG | LWIP_DBG_STATE, ("tftp: timeout, retrying\n")); - resend_data(); - tftp_state.retries++; - } else { - LWIP_DEBUGF(TFTP_DEBUG | LWIP_DBG_STATE, ("tftp: timeout\n")); - close_handle(); - } - } -} - -/** @ingroup tftp - * Initialize TFTP server. - * @param ctx TFTP callback struct - */ -err_t -tftp_init(const struct tftp_context *ctx) -{ - err_t ret; - - struct udp_pcb *pcb = udp_new_ip_type(IPADDR_TYPE_ANY); - if (pcb == NULL) { - return ERR_MEM; - } - - ret = udp_bind(pcb, IP_ANY_TYPE, TFTP_PORT); - if (ret != ERR_OK) { - udp_remove(pcb); - return ret; - } - - tftp_state.handle = NULL; - tftp_state.port = 0; - tftp_state.ctx = ctx; - tftp_state.timer = 0; - tftp_state.last_data = NULL; - tftp_state.upcb = pcb; - - udp_recv(pcb, recv, NULL); - - return ERR_OK; -} - -#endif /* LWIP_UDP */ +/******************************************************************* + * + * @file tftp_server.c + * + * @author Logan Gunthorpe + * Dirk Ziegelmeier + * + * @brief Trivial File Transfer Protocol (RFC 1350) + * + * Copyright (c) Deltatee Enterprises Ltd. 2013 + * 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. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. + * + * Author: Logan Gunthorpe + * Dirk Ziegelmeier + * + */ + +/** + * @defgroup tftp TFTP server + * @ingroup apps + * + * This is simple TFTP server for the lwIP raw API. + */ + +#include "lwip/apps/tftp_server.h" + +#if LWIP_UDP + +#include "lwip/udp.h" +#include "lwip/timeouts.h" +#include "lwip/debug.h" + +#define TFTP_MAX_PAYLOAD_SIZE 512 +#define TFTP_HEADER_LENGTH 4 + +#define TFTP_RRQ 1 +#define TFTP_WRQ 2 +#define TFTP_DATA 3 +#define TFTP_ACK 4 +#define TFTP_ERROR 5 + +enum tftp_error { + TFTP_ERROR_FILE_NOT_FOUND = 1, + TFTP_ERROR_ACCESS_VIOLATION = 2, + TFTP_ERROR_DISK_FULL = 3, + TFTP_ERROR_ILLEGAL_OPERATION = 4, + TFTP_ERROR_UNKNOWN_TRFR_ID = 5, + TFTP_ERROR_FILE_EXISTS = 6, + TFTP_ERROR_NO_SUCH_USER = 7 +}; + +#include + +struct tftp_state { + const struct tftp_context *ctx; + void *handle; + struct pbuf *last_data; + struct udp_pcb *upcb; + ip_addr_t addr; + u16_t port; + int timer; + int last_pkt; + u16_t blknum; + u8_t retries; + u8_t mode_write; +}; + +static struct tftp_state tftp_state; + +static void tftp_tmr(void* arg); + +static void +close_handle(void) +{ + tftp_state.port = 0; + ip_addr_set_any(0, &tftp_state.addr); + + if(tftp_state.last_data != NULL) { + pbuf_free(tftp_state.last_data); + tftp_state.last_data = NULL; + } + + sys_untimeout(tftp_tmr, NULL); + + if (tftp_state.handle) { + tftp_state.ctx->close(tftp_state.handle); + tftp_state.handle = NULL; + LWIP_DEBUGF(TFTP_DEBUG | LWIP_DBG_STATE, ("tftp: closing\n")); + } +} + +static void +send_error(const ip_addr_t *addr, u16_t port, enum tftp_error code, const char *str) +{ + int str_length = strlen(str); + struct pbuf* p; + u16_t* payload; + + p = pbuf_alloc(PBUF_TRANSPORT, (u16_t)(TFTP_HEADER_LENGTH + str_length + 1), PBUF_RAM); + if(p == NULL) { + return; + } + + payload = (u16_t*) p->payload; + payload[0] = PP_HTONS(TFTP_ERROR); + payload[1] = lwip_htons(code); + MEMCPY(&payload[2], str, str_length + 1); + + udp_sendto(tftp_state.upcb, p, addr, port); + pbuf_free(p); +} + +static void +send_ack(u16_t blknum) +{ + struct pbuf* p; + u16_t* payload; + + p = pbuf_alloc(PBUF_TRANSPORT, TFTP_HEADER_LENGTH, PBUF_RAM); + if(p == NULL) { + return; + } + payload = (u16_t*) p->payload; + + payload[0] = PP_HTONS(TFTP_ACK); + payload[1] = lwip_htons(blknum); + udp_sendto(tftp_state.upcb, p, &tftp_state.addr, tftp_state.port); + pbuf_free(p); +} + +static void +resend_data(void) +{ + struct pbuf *p = pbuf_alloc(PBUF_TRANSPORT, tftp_state.last_data->len, PBUF_RAM); + if(p == NULL) { + return; + } + + if(pbuf_copy(p, tftp_state.last_data) != ERR_OK) { + pbuf_free(p); + return; + } + + udp_sendto(tftp_state.upcb, p, &tftp_state.addr, tftp_state.port); + pbuf_free(p); +} + +static void +send_data(void) +{ + u16_t *payload; + int ret; + + if(tftp_state.last_data != NULL) { + pbuf_free(tftp_state.last_data); + } + + tftp_state.last_data = pbuf_alloc(PBUF_TRANSPORT, TFTP_HEADER_LENGTH + TFTP_MAX_PAYLOAD_SIZE, PBUF_RAM); + if(tftp_state.last_data == NULL) { + return; + } + + payload = (u16_t *) tftp_state.last_data->payload; + payload[0] = PP_HTONS(TFTP_DATA); + payload[1] = lwip_htons(tftp_state.blknum); + + ret = tftp_state.ctx->read(tftp_state.handle, &payload[2], TFTP_MAX_PAYLOAD_SIZE); + if (ret < 0) { + send_error(&tftp_state.addr, tftp_state.port, TFTP_ERROR_ACCESS_VIOLATION, "Error occured while reading the file."); + close_handle(); + return; + } + + pbuf_realloc(tftp_state.last_data, (u16_t)(TFTP_HEADER_LENGTH + ret)); + resend_data(); +} + +static void +recv(void *arg, struct udp_pcb *upcb, struct pbuf *p, const ip_addr_t *addr, u16_t port) +{ + u16_t *sbuf = (u16_t *) p->payload; + int opcode; + + LWIP_UNUSED_ARG(arg); + LWIP_UNUSED_ARG(upcb); + + if (((tftp_state.port != 0) && (port != tftp_state.port)) || + (!ip_addr_isany_val(tftp_state.addr) && !ip_addr_cmp(&tftp_state.addr, addr))) { + send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Only one connection at a time is supported"); + pbuf_free(p); + return; + } + + opcode = sbuf[0]; + + tftp_state.last_pkt = tftp_state.timer; + tftp_state.retries = 0; + + switch (opcode) { + case PP_HTONS(TFTP_RRQ): /* fall through */ + case PP_HTONS(TFTP_WRQ): + { + const char tftp_null = 0; + char filename[TFTP_MAX_FILENAME_LEN+1]; + char mode[TFTP_MAX_MODE_LEN+1]; + u16_t filename_end_offset; + u16_t mode_end_offset; + + if(tftp_state.handle != NULL) { + send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Only one connection at a time is supported"); + break; + } + + sys_timeout(TFTP_TIMER_MSECS, tftp_tmr, NULL); + + /* find \0 in pbuf -> end of filename string */ + filename_end_offset = pbuf_memfind(p, &tftp_null, sizeof(tftp_null), 2); + if((u16_t)(filename_end_offset-1) > sizeof(filename)) { + send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Filename too long/not NULL terminated"); + break; + } + pbuf_copy_partial(p, filename, filename_end_offset-1, 2); + + /* find \0 in pbuf -> end of mode string */ + mode_end_offset = pbuf_memfind(p, &tftp_null, sizeof(tftp_null), filename_end_offset+1); + if((u16_t)(mode_end_offset-filename_end_offset) > sizeof(mode)) { + send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Mode too long/not NULL terminated"); + break; + } + pbuf_copy_partial(p, mode, mode_end_offset-filename_end_offset, filename_end_offset+1); + + tftp_state.handle = tftp_state.ctx->open(filename, mode, opcode == PP_HTONS(TFTP_WRQ)); + tftp_state.blknum = 1; + + if (!tftp_state.handle) { + send_error(addr, port, TFTP_ERROR_FILE_NOT_FOUND, "Unable to open requested file."); + break; + } + + LWIP_DEBUGF(TFTP_DEBUG | LWIP_DBG_STATE, ("tftp: %s request from ", (opcode == PP_HTONS(TFTP_WRQ)) ? "write" : "read")); + ip_addr_debug_print(TFTP_DEBUG | LWIP_DBG_STATE, addr); + LWIP_DEBUGF(TFTP_DEBUG | LWIP_DBG_STATE, (" for '%s' mode '%s'\n", filename, mode)); + + ip_addr_copy(tftp_state.addr, *addr); + tftp_state.port = port; + + if (opcode == PP_HTONS(TFTP_WRQ)) { + tftp_state.mode_write = 1; + send_ack(0); + } else { + tftp_state.mode_write = 0; + send_data(); + } + + break; + } + + case PP_HTONS(TFTP_DATA): + { + int ret; + u16_t blknum; + + if (tftp_state.handle == NULL) { + send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "No connection"); + break; + } + + if (tftp_state.mode_write != 1) { + send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Not a write connection"); + break; + } + + blknum = lwip_ntohs(sbuf[1]); + pbuf_header(p, -TFTP_HEADER_LENGTH); + + ret = tftp_state.ctx->write(tftp_state.handle, p); + if (ret < 0) { + send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "error writing file"); + close_handle(); + } else { + send_ack(blknum); + } + + if (p->tot_len < TFTP_MAX_PAYLOAD_SIZE) { + close_handle(); + } + break; + } + + case PP_HTONS(TFTP_ACK): + { + u16_t blknum; + int lastpkt; + + if (tftp_state.handle == NULL) { + send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "No connection"); + break; + } + + if (tftp_state.mode_write != 0) { + send_error(addr, port, TFTP_ERROR_ACCESS_VIOLATION, "Not a read connection"); + break; + } + + blknum = lwip_ntohs(sbuf[1]); + if (blknum != tftp_state.blknum) { + send_error(addr, port, TFTP_ERROR_UNKNOWN_TRFR_ID, "Wrong block number"); + break; + } + + lastpkt = 0; + + if (tftp_state.last_data != NULL) { + lastpkt = tftp_state.last_data->tot_len != (TFTP_MAX_PAYLOAD_SIZE + TFTP_HEADER_LENGTH); + } + + if (!lastpkt) { + tftp_state.blknum++; + send_data(); + } else { + close_handle(); + } + + break; + } + + default: + send_error(addr, port, TFTP_ERROR_ILLEGAL_OPERATION, "Unknown operation"); + break; + } + + pbuf_free(p); +} + +static void +tftp_tmr(void* arg) +{ + LWIP_UNUSED_ARG(arg); + + tftp_state.timer++; + + if (tftp_state.handle == NULL) { + return; + } + + sys_timeout(TFTP_TIMER_MSECS, tftp_tmr, NULL); + + if ((tftp_state.timer - tftp_state.last_pkt) > (TFTP_TIMEOUT_MSECS / TFTP_TIMER_MSECS)) { + if ((tftp_state.last_data != NULL) && (tftp_state.retries < TFTP_MAX_RETRIES)) { + LWIP_DEBUGF(TFTP_DEBUG | LWIP_DBG_STATE, ("tftp: timeout, retrying\n")); + resend_data(); + tftp_state.retries++; + } else { + LWIP_DEBUGF(TFTP_DEBUG | LWIP_DBG_STATE, ("tftp: timeout\n")); + close_handle(); + } + } +} + +/** @ingroup tftp + * Initialize TFTP server. + * @param ctx TFTP callback struct + */ +err_t +tftp_init(const struct tftp_context *ctx) +{ + err_t ret; + + struct udp_pcb *pcb = udp_new_ip_type(IPADDR_TYPE_ANY); + if (pcb == NULL) { + return ERR_MEM; + } + + ret = udp_bind(pcb, IP_ANY_TYPE, TFTP_PORT); + if (ret != ERR_OK) { + udp_remove(pcb); + return ret; + } + + tftp_state.handle = NULL; + tftp_state.port = 0; + tftp_state.ctx = ctx; + tftp_state.timer = 0; + tftp_state.last_data = NULL; + tftp_state.upcb = pcb; + + udp_recv(pcb, recv, NULL); + + return ERR_OK; +} + +#endif /* LWIP_UDP */