summaryrefslogtreecommitdiff
path: root/net
diff options
context:
space:
mode:
authorRavik Hasija <rahasij@linux.microsoft.com>2020-05-18 21:35:43 -0700
committerTom Rini <trini@konsulko.com>2020-06-12 13:17:23 -0400
commit0813921042c363a9c591454144226e67ed21a223 (patch)
treece081bff089c0f15ae3a2bb6dfbe77b8ced85457 /net
parent46c8b18734d273619174006eef498639c06000d3 (diff)
net: tftp: fix option validation as per RFCs
RFC2348, RFC2349: - Option string is case in-sensitive. - Client must generate ERR pkt in case option value mismatch in server OACK - Fix debug print for options Signed-off-by: Ravik Hasija <rahasij@linux.microsoft.com> Reviewed-By: Ramon Fried <rfried.dev@gmail.com>
Diffstat (limited to 'net')
-rw-r--r--net/tftp.c59
1 files changed, 52 insertions, 7 deletions
diff --git a/net/tftp.c b/net/tftp.c
index bbede9c0f2..c05b7b5532 100644
--- a/net/tftp.c
+++ b/net/tftp.c
@@ -70,6 +70,7 @@ enum {
TFTP_ERR_UNEXPECTED_OPCODE = 4,
TFTP_ERR_UNKNOWN_TRANSFER_ID = 5,
TFTP_ERR_FILE_ALREADY_EXISTS = 6,
+ TFTP_ERR_OPTION_NEGOTIATION = 8,
};
static struct in_addr tftp_remote_ip;
@@ -113,6 +114,7 @@ static int tftp_put_final_block_sent;
#define STATE_OACK 5
#define STATE_RECV_WRQ 6
#define STATE_SEND_WRQ 7
+#define STATE_INVALID_OPTION 8
/* default TFTP block size */
#define TFTP_BLOCK_SIZE 512
@@ -318,6 +320,7 @@ static void tftp_send(void)
uchar *xp;
int len = 0;
ushort *s;
+ bool err_pkt = false;
/*
* We will always be sending some sort of packet, so
@@ -388,6 +391,7 @@ static void tftp_send(void)
strcpy((char *)pkt, "File too large");
pkt += 14 /*strlen("File too large")*/ + 1;
len = pkt - xp;
+ err_pkt = true;
break;
case STATE_BAD_MAGIC:
@@ -399,11 +403,28 @@ static void tftp_send(void)
strcpy((char *)pkt, "File has bad magic");
pkt += 18 /*strlen("File has bad magic")*/ + 1;
len = pkt - xp;
+ err_pkt = true;
+ break;
+
+ case STATE_INVALID_OPTION:
+ xp = pkt;
+ s = (ushort *)pkt;
+ *s++ = htons(TFTP_ERROR);
+ *s++ = htons(TFTP_ERR_OPTION_NEGOTIATION);
+ pkt = (uchar *)s;
+ strcpy((char *)pkt, "Option Negotiation Failed");
+ /* strlen("Option Negotiation Failed") + NULL*/
+ pkt += 25 + 1;
+ len = pkt - xp;
+ err_pkt = true;
break;
}
net_send_udp_packet(net_server_ethaddr, tftp_remote_ip,
tftp_remote_port, tftp_our_port, len);
+
+ if (err_pkt)
+ net_set_state(NETLOOP_FAIL);
}
#ifdef CONFIG_CMD_TFTPPUT
@@ -424,6 +445,7 @@ static void tftp_handler(uchar *pkt, unsigned dest, struct in_addr sip,
__be16 proto;
__be16 *s;
int i;
+ u16 timeout_val_rcvd;
if (dest != tftp_our_port) {
return;
@@ -480,8 +502,14 @@ static void tftp_handler(uchar *pkt, unsigned dest, struct in_addr sip,
#endif
case TFTP_OACK:
- debug("Got OACK: %s %s\n",
- pkt, pkt + strlen((char *)pkt) + 1);
+ debug("Got OACK: ");
+ for (i = 0; i < len; i++) {
+ if (pkt[i] == '\0')
+ debug(" ");
+ else
+ debug("%c", pkt[i]);
+ }
+ debug("\n");
tftp_state = STATE_OACK;
tftp_remote_port = src;
/*
@@ -490,15 +518,32 @@ static void tftp_handler(uchar *pkt, unsigned dest, struct in_addr sip,
* something like "len-8" may give a *huge* number
*/
for (i = 0; i+8 < len; i++) {
- if (strcmp((char *)pkt + i, "blksize") == 0) {
+ if (strcasecmp((char *)pkt + i, "blksize") == 0) {
tftp_block_size = (unsigned short)
simple_strtoul((char *)pkt + i + 8,
NULL, 10);
- debug("Blocksize ack: %s, %d\n",
+ debug("Blocksize oack: %s, %d\n",
(char *)pkt + i + 8, tftp_block_size);
+ if (tftp_block_size > tftp_block_size_option) {
+ printf("Invalid blk size(=%d)\n",
+ tftp_block_size);
+ tftp_state = STATE_INVALID_OPTION;
+ }
+ }
+ if (strcasecmp((char *)pkt + i, "timeout") == 0) {
+ timeout_val_rcvd = (unsigned short)
+ simple_strtoul((char *)pkt + i + 8,
+ NULL, 10);
+ debug("Timeout oack: %s, %d\n",
+ (char *)pkt + i + 8, timeout_val_rcvd);
+ if (timeout_val_rcvd != (timeout_ms / 1000)) {
+ printf("Invalid timeout val(=%d s)\n",
+ timeout_val_rcvd);
+ tftp_state = STATE_INVALID_OPTION;
+ }
}
#ifdef CONFIG_TFTP_TSIZE
- if (strcmp((char *)pkt+i, "tsize") == 0) {
+ if (strcasecmp((char *)pkt + i, "tsize") == 0) {
tftp_tsize = simple_strtoul((char *)pkt + i + 6,
NULL, 10);
debug("size = %s, %d\n",
@@ -507,7 +552,7 @@ static void tftp_handler(uchar *pkt, unsigned dest, struct in_addr sip,
#endif
}
#ifdef CONFIG_CMD_TFTPPUT
- if (tftp_put_active) {
+ if (tftp_put_active && tftp_state == STATE_OACK) {
/* Get ready to send the first block */
tftp_state = STATE_DATA;
tftp_cur_block++;
@@ -522,7 +567,7 @@ static void tftp_handler(uchar *pkt, unsigned dest, struct in_addr sip,
tftp_cur_block = ntohs(*(__be16 *)pkt);
if (tftp_state == STATE_SEND_RRQ)
- debug("Server did not acknowledge timeout option!\n");
+ debug("Server did not acknowledge any options!\n");
if (tftp_state == STATE_SEND_RRQ || tftp_state == STATE_OACK ||
tftp_state == STATE_RECV_WRQ) {