diff options
Diffstat (limited to 'fs/tftp.c')
| -rw-r--r-- | fs/tftp.c | 786 |
1 files changed, 687 insertions, 99 deletions
@@ -26,12 +26,18 @@ #include <libgen.h> #include <fcntl.h> #include <getopt.h> +#include <globalvar.h> #include <init.h> +#include <linux/bitmap.h> #include <linux/stat.h> #include <linux/err.h> +#include <linux/kernel.h> #include <kfifo.h> +#include <parseopt.h> #include <linux/sizes.h> +#include "tftp-selftest.h" + #define TFTP_PORT 69 /* Well known TFTP port number */ /* Seconds to wait before remote server is allowed to resend a lost packet */ @@ -58,21 +64,69 @@ #define STATE_WRQ 2 #define STATE_RDATA 3 #define STATE_WDATA 4 -#define STATE_OACK 5 +/* OACK from server has been received and we can begin to sent either the ACK + (for RRQ) or data (for WRQ) */ +#define STATE_START 5 #define STATE_WAITACK 6 #define STATE_LAST 7 #define STATE_DONE 8 #define TFTP_BLOCK_SIZE 512 /* default TFTP block size */ -#define TFTP_FIFO_SIZE 4096 +#define TFTP_MTU_SIZE 1432 /* MTU based block size */ +#define TFTP_MAX_WINDOW_SIZE CONFIG_FS_TFTP_MAX_WINDOW_SIZE + +/* allocate this number of blocks more than needed in the fifo */ +#define TFTP_EXTRA_BLOCKS 2 + +/* size of cache which deals with udp reordering */ +#define TFTP_WINDOW_CACHE_NUM CONFIG_FS_TFTP_REORDER_CACHE_SIZE + +/* marker for an emtpy 'tftp_cache' */ +#define TFTP_CACHE_NO_ID (-1) #define TFTP_ERR_RESEND 1 +#if defined(DEBUG) || IS_ENABLED(CONFIG_SELFTEST_TFTP) +# define debug_assert(_cond) BUG_ON(!(_cond)) +#else +# define debug_assert(_cond) do { \ + if (!(_cond)) \ + __builtin_unreachable(); \ + } while (0) +#endif + +static int g_tftp_window_size = DIV_ROUND_UP(TFTP_MAX_WINDOW_SIZE, 2); + +struct tftp_block { + uint16_t id; + uint16_t len; + + struct list_head head; + uint8_t data[]; +}; + +struct tftp_cache { + /* The id located at @pos or TFTP_CACHE_NO_ID when cache is empty. It + is possible that the corresponding bit in @used is NOT set. */ + unsigned int id; + unsigned int pos; + + /* bitmask */ + unsigned long used[BITS_TO_LONGS(TFTP_WINDOW_CACHE_NUM)]; + + /* size of the cache; is limited by TFTP_WINDOW_CACHE_NUM and the + actual window size */ + unsigned int size; + unsigned int block_len; + struct tftp_block *blocks[TFTP_WINDOW_CACHE_NUM]; +}; + struct file_priv { struct net_connection *tftp_con; int push; uint16_t block; uint16_t last_block; + uint16_t ack_block; int state; int err; char *filename; @@ -82,28 +136,239 @@ struct file_priv { struct kfifo *fifo; void *buf; int blocksize; - int block_requested; + unsigned int windowsize; + bool is_getattr; + struct tftp_cache cache; }; struct tftp_priv { IPaddr_t server; }; +static inline bool is_block_before(uint16_t a, uint16_t b) +{ + return (int16_t)(b - a) > 0; +} + +static inline uint16_t get_block_delta(uint16_t a, uint16_t b) +{ + debug_assert(!is_block_before(b, a)); + + return b - a; +} + +static bool in_window(uint16_t block, uint16_t start, uint16_t end) +{ + /* handle the three cases: + - [ ......... | start | .. | BLOCK | .. | end | ......... ] + - [ ..| BLOCK | .. | end | ................. | start | .. ] + - [ ..| end | ................. | start | .. | BLOCK | .. ] + */ + return ((start <= block && block <= end) || + (block <= end && end <= start) || + (end <= start && start <= block)); +} + +static inline size_t tftp_window_cache_size(struct tftp_cache const *cache) +{ + /* allows to optimize away the cache code when TFTP_WINDOW_CACHE_SIZE + is 0 */ + return TFTP_WINDOW_CACHE_NUM == 0 ? 0 : cache->size; +} + +static void tftp_window_cache_init(struct tftp_cache *cache, + uint16_t block_len, uint16_t window_size) +{ + debug_assert(window_size > 0); + + *cache = (struct tftp_cache) { + .id = TFTP_CACHE_NO_ID, + .block_len = block_len, + .size = min_t(uint16_t, window_size - 1, + ARRAY_SIZE(cache->blocks)), + }; +} + +static void tftp_window_cache_free(struct tftp_cache *cache) +{ + size_t cache_size = tftp_window_cache_size(cache); + size_t i; + + for (i = 0; i < cache_size; ++i) { + free(cache->blocks[i]); + cache->blocks[i] = NULL; + } +} + +static void tftp_window_cache_reset(struct tftp_cache *cache) +{ + cache->id = TFTP_CACHE_NO_ID; + memset(cache->used, 0, sizeof cache->used); +} + +static int tftp_window_cache_get_pos(struct tftp_cache const *cache, uint16_t id) +{ + size_t cache_size = tftp_window_cache_size(cache); + unsigned int pos; + + if (cache_size == 0) + return -1; + + if (cache->id == TFTP_CACHE_NO_ID) + return -1; + + if (!in_window(id, cache->id, cache->id + cache_size - 1)) + return -1; + + pos = cache->pos + get_block_delta(cache->id, id); + pos %= cache_size; + + return pos; +} + +/* returns whether the first cached element has the given @id */ +static bool tftp_window_cache_starts_with(struct tftp_cache const *cache, + uint16_t id) +{ + return (TFTP_WINDOW_CACHE_NUM > 0 && + cache->id != TFTP_CACHE_NO_ID && + cache->id == id && + test_bit(cache->pos, cache->used)); +} + +static bool tftp_window_cache_is_empty(struct tftp_cache const *cache) +{ + /* use this indirection to avoid warnings about a '0 < 0' comparison + in the loop condition when TFTP_WINDOW_CACHE_NUM is zero */ + size_t cache_size = ARRAY_SIZE(cache->used); + size_t i; + + for (i = 0; i < cache_size; ++i) { + if (cache->used[i] != 0) + return false; + } + + return true; +} + +static int tftp_window_cache_insert(struct tftp_cache *cache, uint16_t id, + void const *data, size_t len) +{ + size_t const cache_size = tftp_window_cache_size(cache); + int pos; + struct tftp_block *block; + + if (cache_size == 0) + return -ENOSPC; + + if (cache->id == TFTP_CACHE_NO_ID) { + /* initialize cache when it does not contain elements yet */ + cache->id = id; + cache->pos = 0; + + /* sanity check; cache is expected to be empty */ + debug_assert(tftp_window_cache_is_empty(cache)); + } + + pos = tftp_window_cache_get_pos(cache, id); + if (pos < 0) + return -ENOSPC; + + debug_assert(pos < cache_size); + + if (test_bit(pos, cache->used)) + /* block already cached */ + return 0; + + block = cache->blocks[pos]; + if (!block) { + /* allocate space for the block; after being released, this + memory can be reused for other blocks during the same tftp + transfer */ + block = malloc(sizeof *block + cache->block_len); + if (!block) + return -ENOMEM; + + cache->blocks[pos] = block; + } + + __set_bit(pos, cache->used); + memcpy(block->data, data, len); + block->id = id; + block->len = len; + + return 0; +} + +/* Marks the element at 'pos' as unused and updates internal cache information. + Returns true iff element at pos was valid. */ +static bool tftp_window_cache_remove(struct tftp_cache *cache, unsigned int pos) +{ + size_t const cache_size = tftp_window_cache_size(cache); + bool res; + + if (cache_size == 0) + return 0; + + res = __test_and_clear_bit(pos, cache->used); + + if (tftp_window_cache_is_empty(cache)) { + /* cache has been cleared; reset pointers */ + cache->id = TFTP_CACHE_NO_ID; + } else if (pos != cache->pos) { + /* noop; elements has been removed from the middle of cache */ + } else { + /* first element of cache has been removed; proceed to the + next one */ + cache->id += 1; + cache->pos += 1; + cache->pos %= cache_size; + } + + return res; +} + +/* Releases the first element from the cache and returns its content. + * + * Function can return NULL when the element is not cached + */ +static struct tftp_block *tftp_window_cache_pop(struct tftp_cache *cache) +{ + unsigned int pos = cache->pos; + + debug_assert(cache->id != TFTP_CACHE_NO_ID); + + if (!tftp_window_cache_remove(cache, pos)) + return NULL; + + return cache->blocks[pos]; +} + +static bool tftp_window_cache_remove_id(struct tftp_cache *cache, uint16_t id) +{ + int pos = tftp_window_cache_get_pos(cache, id); + + if (pos < 0) + return false; + + return tftp_window_cache_remove(cache, pos); +} + static int tftp_truncate(struct device_d *dev, FILE *f, loff_t size) { return 0; } -static char *tftp_states[] = { +static char const * const tftp_states[] = { [STATE_INVALID] = "INVALID", [STATE_RRQ] = "RRQ", [STATE_WRQ] = "WRQ", [STATE_RDATA] = "RDATA", [STATE_WDATA] = "WDATA", - [STATE_OACK] = "OACK", [STATE_WAITACK] = "WAITACK", [STATE_LAST] = "LAST", [STATE_DONE] = "DONE", + [STATE_START] = "START", }; static int tftp_send(struct file_priv *priv) @@ -112,6 +377,7 @@ static int tftp_send(struct file_priv *priv) int len = 0; uint16_t *s; unsigned char *pkt = net_udp_get_payload(priv->tftp_con); + unsigned int window_size; int ret; pr_vdebug("%s: state %s\n", __func__, tftp_states[priv->state]); @@ -119,6 +385,15 @@ static int tftp_send(struct file_priv *priv) switch (priv->state) { case STATE_RRQ: case STATE_WRQ: + if (priv->push || priv->is_getattr) + /* atm, windowsize is supported only for RRQ and there + is no need to request a full window when we are + just looking up file attributes */ + window_size = 1; + else + window_size = min_t(unsigned int, g_tftp_window_size, + TFTP_MAX_WINDOW_SIZE); + xp = pkt; s = (uint16_t *)pkt; if (priv->state == STATE_RRQ) @@ -131,32 +406,45 @@ static int tftp_send(struct file_priv *priv) "octet%c" "timeout%c" "%d%c" - "tsize%c" - "%lld%c" "blksize%c" - "1432", - priv->filename + 1, 0, - 0, - 0, - TIMEOUT, 0, - 0, - priv->filesize, 0, - 0); + "%u", + priv->filename + 1, '\0', + '\0', /* "octet" */ + '\0', /* "timeout" */ + TIMEOUT, '\0', + '\0', /* "blksize" */ + /* use only a minimal blksize for getattr + operations, */ + priv->is_getattr ? TFTP_BLOCK_SIZE : TFTP_MTU_SIZE); pkt++; + + if (!priv->push) + /* we do not know the filesize in WRQ requests and + 'priv->filesize' will always be zero */ + pkt += sprintf((unsigned char *)pkt, + "tsize%c%lld%c", + '\0', priv->filesize, + '\0'); + + if (window_size > 1) + pkt += sprintf((unsigned char *)pkt, + "windowsize%c%u%c", + '\0', window_size, + '\0'); + len = pkt - xp; break; case STATE_RDATA: - if (priv->block == priv->block_requested) - return 0; - case STATE_OACK: xp = pkt; s = (uint16_t *)pkt; *s++ = htons(TFTP_ACK); - *s++ = htons(priv->block); - priv->block_requested = priv->block; + *s++ = htons(priv->last_block); + priv->ack_block = priv->last_block; + priv->ack_block += priv->windowsize; pkt = (unsigned char *)s; len = pkt - xp; + tftp_window_cache_reset(&priv->cache); break; } @@ -197,7 +485,6 @@ static int tftp_poll(struct file_priv *priv) if (is_timeout(priv->resend_timeout, TFTP_RESEND_TIMEOUT)) { printf("T "); priv->resend_timeout = get_time_ns(); - priv->block_requested = -1; return TFTP_ERR_RESEND; } @@ -212,7 +499,7 @@ static int tftp_poll(struct file_priv *priv) return 0; } -static void tftp_parse_oack(struct file_priv *priv, unsigned char *pkt, int len) +static int tftp_parse_oack(struct file_priv *priv, unsigned char *pkt, int len) { unsigned char *opt, *val, *s; @@ -229,14 +516,25 @@ static void tftp_parse_oack(struct file_priv *priv, unsigned char *pkt, int len) opt = s; val = s + strlen(s) + 1; if (val > s + len) - return; + break; if (!strcmp(opt, "tsize")) priv->filesize = simple_strtoull(val, NULL, 10); if (!strcmp(opt, "blksize")) priv->blocksize = simple_strtoul(val, NULL, 10); + if (!strcmp(opt, "windowsize")) + priv->windowsize = simple_strtoul(val, NULL, 10); pr_debug("OACK opt: %s val: %s\n", opt, val); s = val + strlen(val) + 1; } + + if (priv->blocksize > TFTP_MTU_SIZE || + priv->windowsize > TFTP_MAX_WINDOW_SIZE || + priv->windowsize == 0) { + pr_warn("tftp: invalid oack response\n"); + return -EINVAL; + } + + return 0; } static void tftp_timer_reset(struct file_priv *priv) @@ -244,10 +542,126 @@ static void tftp_timer_reset(struct file_priv *priv) priv->progress_timeout = priv->resend_timeout = get_time_ns(); } +static int tftp_allocate_transfer(struct file_priv *priv) +{ + debug_assert(!priv->fifo); + debug_assert(!priv->buf); + + /* multiplication is safe; both operands were checked in tftp_parse_oack() + and are small integers */ + priv->fifo = kfifo_alloc(priv->blocksize * + (priv->windowsize + TFTP_EXTRA_BLOCKS)); + if (!priv->fifo) + goto err; + + if (priv->push) { + priv->buf = xmalloc(priv->blocksize); + if (!priv->buf) { + kfifo_free(priv->fifo); + priv->fifo = NULL; + goto err; + } + } else { + tftp_window_cache_init(&priv->cache, + priv->blocksize, priv->windowsize); + } + + return 0; + +err: + priv->err = -ENOMEM; + priv->state = STATE_DONE; + + return priv->err; +} + +static void tftp_put_data(struct file_priv *priv, uint16_t block, + void const *pkt, size_t len) +{ + unsigned int sz; + + if (len > priv->blocksize) { + pr_warn("tftp: oversized packet (%zu > %d) received\n", + len, priv->blocksize); + return; + } + + priv->last_block = block; + + sz = kfifo_put(priv->fifo, pkt, len); + + if (sz != len) { + pr_err("tftp: not enough room in kfifo (only %u out of %zu written)\n", + sz, len); + priv->err = -ENOMEM; + priv->state = STATE_DONE; + } else if (len < priv->blocksize) { + tftp_send(priv); + priv->err = 0; + priv->state = STATE_DONE; + } +} + +static void tftp_apply_window_cache(struct file_priv *priv) +{ + struct tftp_cache *cache = &priv->cache; + + while (tftp_window_cache_starts_with(cache, priv->last_block + 1)) { + struct tftp_block *block; + + /* can be changed by tftp_put_data() below and must be + checked in each loop */ + if (priv->state != STATE_RDATA) + return; + + block = tftp_window_cache_pop(cache); + + debug_assert(block); + debug_assert(block->id == (uint16_t)(priv->last_block + 1)); + + tftp_put_data(priv, block->id, block->data, block->len); + } +} + +static void tftp_handle_data(struct file_priv *priv, uint16_t block, + void const *data, size_t len) +{ + uint16_t exp_block; + int rc; + + exp_block = priv->last_block + 1; + + if (exp_block == block) { + /* datagram over network is the expected one; put it in the + fifo directly and try to apply cached items then */ + tftp_timer_reset(priv); + tftp_put_data(priv, block, data, len); + tftp_window_cache_remove_id(&priv->cache, block); + tftp_apply_window_cache(priv); + } else if (!in_window(block, exp_block, priv->ack_block)) { + /* completely unexpected and unrelated to actual window; + ignore the packet. */ + printf("B"); + } else { + /* The 'rc < 0' below happens e.g. when datagrams in the first + part of the transfer window are dropped. + + TODO: this will usually result in a timeout + (TFTP_RESEND_TIMEOUT). It should be possible to bypass + this timeout by acknowledging the last packet (e.g. by + doing 'priv->ack_block = priv->last_block' here). */ + rc = tftp_window_cache_insert(&priv->cache, block, data, len); + if (rc < 0) + printf("M"); + } +} + static void tftp_recv(struct file_priv *priv, uint8_t *pkt, unsigned len, uint16_t uh_sport) { uint16_t opcode; + uint16_t block; + int rc; /* according to RFC1350 minimal tftp packet length is 4 bytes */ if (len < 4) @@ -270,75 +684,80 @@ static void tftp_recv(struct file_priv *priv, if (!priv->push) break; - priv->block = ntohs(*(uint16_t *)pkt); - if (priv->block != priv->last_block) { - pr_vdebug("ack %d != %d\n", priv->block, priv->last_block); + block = ntohs(*(uint16_t *)pkt); + if (block != priv->last_block) { + pr_vdebug("ack %d != %d\n", block, priv->last_block); break; } - priv->block++; + switch (priv->state) { + case STATE_WRQ: + priv->tftp_con->udp->uh_dport = uh_sport; + priv->state = STATE_START; + break; - tftp_timer_reset(priv); + case STATE_WAITACK: + priv->state = STATE_WDATA; + break; - if (priv->state == STATE_LAST) { + case STATE_LAST: priv->state = STATE_DONE; break; + + default: + pr_warn("ACK packet in %s state\n", + tftp_states[priv->state]); + goto ack_out; } - priv->tftp_con->udp->uh_dport = uh_sport; - priv->state = STATE_WDATA; + + priv->block = block + 1; + tftp_timer_reset(priv); + + ack_out: break; case TFTP_OACK: - tftp_parse_oack(priv, pkt, len); + if (priv->state != STATE_RRQ && priv->state != STATE_WRQ) { + pr_warn("OACK packet in %s state\n", + tftp_states[priv->state]); + break; + } + priv->tftp_con->udp->uh_dport = uh_sport; - if (priv->push) { - /* send first block */ - priv->state = STATE_WDATA; - priv->block = 1; - } else { - /* send ACK */ - priv->state = STATE_OACK; - priv->block = 0; - tftp_send(priv); + if (tftp_parse_oack(priv, pkt, len) < 0) { + priv->err = -EINVAL; + priv->state = STATE_DONE; + break; } + priv->state = STATE_START; break; + case TFTP_DATA: len -= 2; - priv->block = ntohs(*(uint16_t *)pkt); + block = ntohs(*(uint16_t *)pkt); - if (priv->state == STATE_RRQ || priv->state == STATE_OACK) { - /* first block received */ - priv->state = STATE_RDATA; + if (priv->state == STATE_RRQ) { + /* first block received; entered only with non rfc + 2347 (TFTP Option extension) compliant servers */ priv->tftp_con->udp->uh_dport = uh_sport; + priv->state = STATE_RDATA; priv->last_block = 0; + priv->ack_block = priv->windowsize; - if (priv->block != 1) { /* Assertion */ - pr_err("error: First block is not block 1 (%d)\n", - priv->block); - priv->err = -EINVAL; - priv->state = STATE_DONE; + rc = tftp_allocate_transfer(priv); + if (rc < 0) break; - } } - if (priv->block == priv->last_block) - /* Same block again; ignore it. */ + if (priv->state != STATE_RDATA) { + pr_warn("DATA packet in %s state\n", + tftp_states[priv->state]); break; - - priv->last_block = priv->block; - - tftp_timer_reset(priv); - - kfifo_put(priv->fifo, pkt + 2, len); - - if (len < priv->blocksize) { - tftp_send(priv); - priv->err = 0; - priv->state = STATE_DONE; } + tftp_handle_data(priv, block, pkt + 2, len); break; case TFTP_ERROR: @@ -369,13 +788,38 @@ static void tftp_handler(void *ctx, char *packet, unsigned len) tftp_recv(priv, pkt, net_eth_to_udplen(packet), udp->uh_sport); } +static int tftp_start_transfer(struct file_priv *priv) +{ + int rc; + + rc = tftp_allocate_transfer(priv); + if (rc < 0) + /* function sets 'priv->state = STATE_DONE' and 'priv->err' in + error case */ + return rc; + + if (priv->push) { + /* send first block */ + priv->state = STATE_WDATA; + priv->block = 1; + } else { + /* send ACK */ + priv->state = STATE_RDATA; + priv->last_block = 0; + tftp_send(priv); + } + + return 0; +} + static struct file_priv *tftp_do_open(struct device_d *dev, - int accmode, struct dentry *dentry) + int accmode, struct dentry *dentry, bool is_getattr) { struct fs_device_d *fsdev = dev_to_fs_device(dev); struct file_priv *priv; struct tftp_priv *tpriv = dev->priv; int ret; + unsigned short port = TFTP_PORT; priv = xzalloc(sizeof(*priv)); @@ -397,49 +841,77 @@ static struct file_priv *tftp_do_open(struct device_d *dev, priv->err = -EINVAL; priv->filename = dpath(dentry, fsdev->vfsmount.mnt_root); priv->blocksize = TFTP_BLOCK_SIZE; - priv->block_requested = -1; + priv->windowsize = 1; + priv->is_getattr = is_getattr; - priv->fifo = kfifo_alloc(TFTP_FIFO_SIZE); - if (!priv->fifo) { - ret = -ENOMEM; - goto out; - } + parseopt_hu(fsdev->options, "port", &port); - priv->tftp_con = net_udp_new(tpriv->server, TFTP_PORT, tftp_handler, - priv); + priv->tftp_con = net_udp_new(tpriv->server, port, tftp_handler, priv); if (IS_ERR(priv->tftp_con)) { ret = PTR_ERR(priv->tftp_con); - goto out1; + goto out; } ret = tftp_send(priv); if (ret) - goto out2; + goto out1; tftp_timer_reset(priv); - while (priv->state != STATE_RDATA && - priv->state != STATE_DONE && - priv->state != STATE_WDATA) { - ret = tftp_poll(priv); - if (ret == TFTP_ERR_RESEND) - tftp_send(priv); - if (ret < 0) - goto out2; - } - if (priv->state == STATE_DONE && priv->err) { - ret = priv->err; - goto out2; - } + /* - 'ret < 0' ... error + - 'ret == 0' ... further tftp_poll() required + - 'ret == 1' ... startup finished */ + do { + switch (priv->state) { + case STATE_DONE: + /* branch is entered in two situations: + - non rfc 2347 compliant servers finished the + transfer by sending a small file + - some error occurred */ + if (priv->err < 0) + ret = priv->err; + else + ret = 1; + break; + + case STATE_START: + ret = tftp_start_transfer(priv); + if (!ret) + ret = 1; + break; + + case STATE_RDATA: + /* first data block of non rfc 2347 servers */ + ret = 1; + break; + + case STATE_RRQ: + case STATE_WRQ: + ret = tftp_poll(priv); + if (ret == TFTP_ERR_RESEND) { + tftp_send(priv); + ret = 0; + } + break; + + default: + debug_assert(false); + break; + } + } while (ret == 0); - priv->buf = xmalloc(priv->blocksize); + if (ret < 0) + goto out1; return priv; -out2: - net_unregister(priv->tftp_con); out1: - kfifo_free(priv->fifo); + net_unregister(priv->tftp_con); out: + if (priv->fifo) + kfifo_free(priv->fifo); + + free(priv->filename); + free(priv->buf); free(priv); return ERR_PTR(ret); @@ -449,7 +921,7 @@ static int tftp_open(struct device_d *dev, FILE *file, const char *filename) { struct file_priv *priv; - priv = tftp_do_open(dev, file->flags, file->dentry); + priv = tftp_do_open(dev, file->flags, file->dentry, false); if (IS_ERR(priv)) return PTR_ERR(priv); @@ -489,6 +961,7 @@ static int tftp_do_close(struct file_priv *priv) } net_unregister(priv->tftp_con); + tftp_window_cache_free(&priv->cache); kfifo_free(priv->fifo); free(priv->filename); free(priv->buf); @@ -544,7 +1017,7 @@ static int tftp_read(struct device_d *dev, FILE *f, void *buf, size_t insize) { struct file_priv *priv = f->priv; size_t outsize = 0, now; - int ret; + int ret = 0; pr_vdebug("%s %zu\n", __func__, insize); @@ -553,19 +1026,30 @@ static int tftp_read(struct device_d *dev, FILE *f, void *buf, size_t insize) outsize += now; buf += now; insize -= now; - if (priv->state == STATE_DONE) - return outsize; - if (TFTP_FIFO_SIZE - kfifo_len(priv->fifo) >= priv->blocksize) + if (priv->state == STATE_DONE) { + ret = priv->err; + break; + } + + /* send the ACK only when fifo has been nearly depleted; else, + when tftp_read() is called with small 'insize' values, it + is possible that there is read more data from the network + than consumed by kfifo_get() and the fifo overflows */ + if (priv->last_block == priv->ack_block && + kfifo_len(priv->fifo) <= TFTP_EXTRA_BLOCKS * priv->blocksize) tftp_send(priv); ret = tftp_poll(priv); if (ret == TFTP_ERR_RESEND) tftp_send(priv); if (ret < 0) - return ret; + break; } + if (ret < 0) + return ret; + return outsize; } @@ -665,7 +1149,7 @@ static struct dentry *tftp_lookup(struct inode *dir, struct dentry *dentry, struct file_priv *priv; loff_t filesize; - priv = tftp_do_open(&fsdev->dev, O_RDONLY, dentry); + priv = tftp_do_open(&fsdev->dev, O_RDONLY, dentry, true); if (IS_ERR(priv)) return NULL; @@ -748,6 +1232,110 @@ static struct fs_driver_d tftp_driver = { static int tftp_init(void) { + globalvar_add_simple_int("tftp.windowsize", &g_tftp_window_size, "%u"); + return register_fs_driver(&tftp_driver); } coredevice_initcall(tftp_init); + + +BSELFTEST_GLOBALS(); + +static int __maybe_unused tftp_window_cache_selftest(void) +{ + struct tftp_cache *cache = malloc(sizeof *cache); + + if (!cache) + return -ENOMEM; + + (void)skipped_tests; + + expect_it( is_block_before(0, 1)); + expect_it(!is_block_before(1, 0)); + expect_it( is_block_before(65535, 0)); + expect_it(!is_block_before(0, 65535)); + + expect_eq(get_block_delta(0, 1), 1); + expect_eq(get_block_delta(65535, 0), 1); + expect_eq(get_block_delta(65535, 1), 2); + + expect_it(!in_window(0, 1, 3)); + expect_it( in_window(1, 1, 3)); + expect_it( in_window(2, 1, 3)); + expect_it( in_window(3, 1, 3)); + expect_it(!in_window(4, 1, 3)); + + expect_it(!in_window(65534, 65535, 1)); + expect_it( in_window(65535, 65535, 1)); + expect_it( in_window( 0, 65535, 1)); + expect_it( in_window( 1, 65535, 1)); + expect_it(!in_window( 2, 65535, 1)); + + + tftp_window_cache_init(cache, 512, 5); + + if (tftp_window_cache_size(cache) < 4) + goto out; + + expect_eq(tftp_window_cache_size(cache), 4); + + /* sequence 1 */ + expect_ok (tftp_window_cache_insert(cache, 20, "20", 2)); + expect_ok (tftp_window_cache_insert(cache, 22, "22", 2)); + expect_ok (tftp_window_cache_insert(cache, 21, "21", 2)); + expect_ok (tftp_window_cache_insert(cache, 23, "23", 2)); + expect_err(tftp_window_cache_insert(cache, 24, "24", 2)); + expect_err(tftp_window_cache_insert(cache, 19, "19", 2)); + expect_ok (tftp_window_cache_insert(cache, 22, "22", 2)); + expect_ok (tftp_window_cache_insert(cache, 20, "20", 2)); + + expect_eq(tftp_window_cache_pop(cache)->id, 20); + expect_eq(tftp_window_cache_pop(cache)->id, 21); + expect_eq(tftp_window_cache_pop(cache)->id, 22); + expect_eq(tftp_window_cache_pop(cache)->id, 23); + expect_eq(cache->id, TFTP_CACHE_NO_ID); + + /* sequence 2 */ + expect_ok (tftp_window_cache_insert(cache, 30, "30", 2)); + expect_ok (tftp_window_cache_insert(cache, 32, "32", 2)); + expect_err(tftp_window_cache_insert(cache, 34, "34", 2)); + + expect_it(tftp_window_cache_starts_with(cache, 30)); + expect_eq(tftp_window_cache_pop(cache)->id, 30); + + expect_ok (tftp_window_cache_insert(cache, 34, "34", 2)); + expect_err(tftp_window_cache_insert(cache, 35, "35", 2)); + + expect_it(!tftp_window_cache_starts_with(cache, 30)); + expect_it(!tftp_window_cache_starts_with(cache, 31)); + expect_it(!tftp_window_cache_starts_with(cache, 32)); + expect_NULL(tftp_window_cache_pop(cache)); + + expect_it(tftp_window_cache_starts_with(cache, 32)); + expect_eq(tftp_window_cache_pop(cache)->id, 32); + + expect_NULL(tftp_window_cache_pop(cache)); + expect_eq(tftp_window_cache_pop(cache)->id, 34); + + expect_eq(cache->id, TFTP_CACHE_NO_ID); + + /* sequence 3 */ + expect_ok(tftp_window_cache_insert(cache, 40, "40", 2)); + expect_ok(tftp_window_cache_insert(cache, 42, "42", 2)); + expect_ok(tftp_window_cache_insert(cache, 43, "43", 2)); + + expect_it(!tftp_window_cache_remove_id(cache, 30)); + expect_it(!tftp_window_cache_remove_id(cache, 41)); + expect_it(!tftp_window_cache_remove_id(cache, 44)); + + expect_it( tftp_window_cache_remove_id(cache, 42)); + expect_it(!tftp_window_cache_remove_id(cache, 42)); + +out: + tftp_window_cache_free(cache); + + return 0; +} +#ifdef CONFIG_SELFTEST_TFTP +bselftest(core, tftp_window_cache_selftest); +#endif |