Fate #303031: Circumvent TFTP size restrictions in atftpd The size of a single image file that can be transferred with TFTP is limited to 2^(2*8) *BLOCKSIZE (as per RFC 1350 there are only two bytes for the block counter). This is problematic for one of our customers who needs to transfer 100+ MB Windows images using a TFTP client (NT bootloader) which has a hardwared BLOCKSIZE setting of 1432). block rollover http://www.compuphase.com/tftp.htm Patch originally from OpenSUSE: https://build.opensuse.org/package/view_file/openSUSE:Leap:42.2/atftp/atftpd-0.7_circumvent_tftp_size_restrictions.patch?expand=1 Modified to apply for atftp-0.7.1 used in PhotonOS diff --git a/tftp_def.h b/tftp_def.h.new index e4b338d..6849d6f 100644 --- a/tftp_def.h +++ b/tftp_def.h.new @@ -32,6 +32,7 @@ #define TIMEOUT 5 /* Client timeout */ #define S_TIMEOUT 5 /* Server timout. */ #define NB_OF_RETRY 5 +#define MAXBLOCKS 1000000 /* maximum number of blocks in a download */ /* definition to use tftp_options structure */ #define OPT_FILENAME 0 diff --git a/tftp_file.c b/tftp_file.c.new index 27ae4d0..baab66c 100644 --- a/tftp_file.c +++ b/tftp_file.c.new @@ -622,8 +622,8 @@ int tftp_send_file(struct client_data *data) int state = S_SEND_REQ; /* current state in the state machine */ int timeout_state = state; /* what state should we go on when timeout */ int result; - int block_number = 0; - int last_block = -1; + long block_number = 0; + long last_block = -1; int data_size; /* size of data received */ int sockfd = data->sockfd; /* just to simplify calls */ struct sockaddr_storage sa; /* a copy of data.sa_peer */ @@ -637,8 +637,8 @@ int tftp_send_file(struct client_data *data) int convert = 0; /* if true, do netascii convertion */ char string[MAXLEN]; - int prev_block_number = 0; /* needed to support netascii convertion */ - int prev_file_pos = 0; + long prev_block_number = 0; /* needed to support netascii convertion */ + long prev_file_pos = 0; int temp = 0; data->file_size = 0; @@ -745,7 +745,7 @@ int tftp_send_file(struct client_data *data) data_size, data->data_buffer); data->file_size += data_size; if (data->trace) - fprintf(stderr, "sent DATA <block: %d, size: %d>\n", + fprintf(stderr, "sent DATA <block: %ld, size: %d>\n", block_number + 1, data_size - 4); state = S_WAIT_PACKET; break; @@ -785,7 +785,7 @@ int tftp_send_file(struct client_data *data) } block_number = ntohs(tftphdr->th_block); if (data->trace) - fprintf(stderr, "received ACK <block: %d>\n", + fprintf(stderr, "received ACK <block: %ld>\n", block_number); if ((last_block != -1) && (block_number > last_block)) { diff --git a/tftp_io.c b/tftp_io.c.new index 605a9c2..b559d5a 100644 --- a/tftp_io.c +++ b/tftp_io.c.new @@ -350,8 +350,8 @@ int tftp_get_packet(int sock1, int sock2, int *sock, struct sockaddr_storage *sa /* * Read from file and do netascii conversion if needed */ -int tftp_file_read(FILE *fp, char *data_buffer, int data_buffer_size, int block_number, - int convert, int *prev_block_number, int *prev_file_pos, int *temp) +int tftp_file_read(FILE *fp, char *data_buffer, int data_buffer_size, long block_number, + int convert, long *prev_block_number, long *prev_file_pos, int *temp) { int i; int c; diff --git a/tftp_io.h b/tftp_io.h.new index da8c369..7840744 100644 --- a/tftp_io.h +++ b/tftp_io.h.new @@ -52,8 +52,8 @@ int tftp_send_data(int socket, struct sockaddr_storage *s_inn, short block_numbe int tftp_get_packet(int sock1, int sock2, int *sock, struct sockaddr_storage *sa, struct sockaddr_storage *from, struct sockaddr_storage *to, int timeout, int *size, char *data); -int tftp_file_read(FILE *fp, char *buffer, int buffer_size, int block_number, int convert, - int *prev_block_number, int *prev_file_pos, int *temp); +int tftp_file_read(FILE *fp, char *buffer, int buffer_size, long block_number, int convert, + long *prev_block_number, long *prev_file_pos, int *temp); int tftp_file_write(FILE *fp, char *data_buffer, int data_buffer_size, int block_number, int data_size, int convert, int *prev_block_number, int *temp); #endif diff --git a/tftpd_file.c b/tftpd_file.c.new index da1d6c9..3b37f94 100644 --- a/tftpd_file.c +++ b/tftpd_file.c.new @@ -407,8 +407,9 @@ int tftpd_send_file(struct thread_data *data) int state = S_BEGIN; int timeout_state = state; int result; - int block_number = 0; - int last_block = -1; + long block_number = 0; + long last_block = -1; + int block_loops = 0; int data_size; struct sockaddr_storage *sa = &data->client_info->client; struct sockaddr_storage from; @@ -431,8 +432,8 @@ int tftpd_send_file(struct thread_data *data) struct client_info *client_old = NULL; struct tftp_opt options[OPT_NUMBER]; - int prev_block_number = 0; /* needed to support netascii convertion */ - int prev_file_pos = 0; + long prev_block_number = 0; /* needed to support netascii convertion */ + long prev_file_pos = 0; int temp = 0; /* look for mode option */ @@ -565,11 +566,12 @@ int tftpd_send_file(struct thread_data *data) logger(LOG_INFO, "blksize option -> %d", result); } - /* Verify that the file can be sent in 2^16 block of BLKSIZE octets */ - if ((file_stat.st_size / (data->data_buffer_size - 4)) > 65535) + /* Verify that the file can be sent in MAXBLOCKS blocks of BLKSIZE octets */ + if ((file_stat.st_size / (data->data_buffer_size - 4)) > MAXBLOCKS) { tftp_send_error(sockfd, sa, EUNDEF, data->data_buffer, data->data_buffer_size); - logger(LOG_NOTICE, "Requested file to big, increase BLKSIZE"); + logger(LOG_NOTICE, "Requested file too big, increase BLKSIZE"); + logger(LOG_NOTICE, "Only %d blocks of %d bytes can be served.", MAXBLOCKS, data->data_buffer_size); if (data->trace) logger(LOG_DEBUG, "sent ERROR <code: %d, msg: %s>", EUNDEF, tftp_errmsg[EUNDEF]); @@ -880,10 +882,15 @@ int tftpd_send_file(struct thread_data *data) } /* The ACK is from the current client */ number_of_timeout = 0; - block_number = ntohs(tftphdr->th_block); + block_number = (block_loops * 65536) + ntohs(tftphdr->th_block); if (data->trace) - logger(LOG_DEBUG, "received ACK <block: %d>", - block_number); + { + logger(LOG_DEBUG, "received ACK <block: %d>", block_number); + } + if (ntohs(tftphdr->th_block) == 65535) + { + block_loops++; + }; if ((last_block != -1) && (block_number > last_block)) { state = S_END;