/*
* tftp.c - a simple, read-only tftp server for qemu
- *
+ *
* Copyright (c) 2004 Magnus Damm <damm@opensource.se>
- *
+ *
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
*/
#include <slirp.h>
+#include "qemu-common.h" // for pstrcpy
struct tftp_session {
int in_use;
unsigned char filename[TFTP_FILENAME_MAX];
-
+
struct in_addr client_ip;
u_int16_t client_port;
-
+
int timestamp;
};
-struct tftp_session tftp_sessions[TFTP_SESSIONS_MAX];
+static struct tftp_session tftp_sessions[TFTP_SESSIONS_MAX];
-const char *tftp_prefix;
+char *tftp_prefix;
static void tftp_session_update(struct tftp_session *spt)
{
{
int fd;
int bytes_read = 0;
+ char buffer[1024];
+ int n;
+
+ n = snprintf(buffer, sizeof(buffer), "%s/%s",
+ tftp_prefix, spt->filename);
+ if (n >= sizeof(buffer))
+ return -1;
- fd = open(spt->filename, O_RDONLY);
+ fd = open(buffer, O_RDONLY | O_BINARY);
if (fd < 0) {
return -1;
return bytes_read;
}
-static int tftp_send_error(struct tftp_session *spt,
+static int tftp_send_oack(struct tftp_session *spt,
+ const char *key, uint32_t value,
+ struct tftp_t *recv_tp)
+{
+ struct sockaddr_in saddr, daddr;
+ struct mbuf *m;
+ struct tftp_t *tp;
+ int n = 0;
+
+ m = m_get();
+
+ if (!m)
+ return -1;
+
+ memset(m->m_data, 0, m->m_size);
+
+ m->m_data += IF_MAXLINKHDR;
+ tp = (void *)m->m_data;
+ m->m_data += sizeof(struct udpiphdr);
+
+ tp->tp_op = htons(TFTP_OACK);
+ n += snprintf((char *)tp->x.tp_buf + n, sizeof(tp->x.tp_buf) - n, "%s",
+ key) + 1;
+ n += snprintf((char *)tp->x.tp_buf + n, sizeof(tp->x.tp_buf) - n, "%u",
+ value) + 1;
+
+ saddr.sin_addr = recv_tp->ip.ip_dst;
+ saddr.sin_port = recv_tp->udp.uh_dport;
+
+ daddr.sin_addr = spt->client_ip;
+ daddr.sin_port = spt->client_port;
+
+ m->m_len = sizeof(struct tftp_t) - 514 + n -
+ sizeof(struct ip) - sizeof(struct udphdr);
+ udp_output2(NULL, m, &saddr, &daddr, IPTOS_LOWDELAY);
+
+ return 0;
+}
+
+
+
+static int tftp_send_error(struct tftp_session *spt,
u_int16_t errorcode, const char *msg,
struct tftp_t *recv_tp)
{
memset(m->m_data, 0, m->m_size);
- m->m_data += if_maxlinkhdr;
+ m->m_data += IF_MAXLINKHDR;
tp = (void *)m->m_data;
m->m_data += sizeof(struct udpiphdr);
-
+
tp->tp_op = htons(TFTP_ERROR);
tp->x.tp_error.tp_error_code = htons(errorcode);
- strcpy(tp->x.tp_error.tp_msg, msg);
+ pstrcpy((char *)tp->x.tp_error.tp_msg, sizeof(tp->x.tp_error.tp_msg), msg);
saddr.sin_addr = recv_tp->ip.ip_dst;
saddr.sin_port = recv_tp->udp.uh_dport;
nobytes = 2;
- m->m_len = sizeof(struct tftp_t) - 514 + 3 + strlen(msg) -
+ m->m_len = sizeof(struct tftp_t) - 514 + 3 + strlen(msg) -
sizeof(struct ip) - sizeof(struct udphdr);
udp_output2(NULL, m, &saddr, &daddr, IPTOS_LOWDELAY);
return 0;
}
-static int tftp_send_data(struct tftp_session *spt,
+static int tftp_send_data(struct tftp_session *spt,
u_int16_t block_nr,
struct tftp_t *recv_tp)
{
memset(m->m_data, 0, m->m_size);
- m->m_data += if_maxlinkhdr;
+ m->m_data += IF_MAXLINKHDR;
tp = (void *)m->m_data;
m->m_data += sizeof(struct udpiphdr);
-
+
tp->tp_op = htons(TFTP_DATA);
tp->x.tp_data.tp_block_nr = htons(block_nr);
return -1;
}
- m->m_len = sizeof(struct tftp_t) - (512 - nobytes) -
+ m->m_len = sizeof(struct tftp_t) - (512 - nobytes) -
sizeof(struct ip) - sizeof(struct udphdr);
udp_output2(NULL, m, &saddr, &daddr, IPTOS_LOWDELAY);
else {
return;
}
-
+
if (src[k] == '\0') {
break;
}
}
-
+
if (k >= n) {
return;
}
-
+
k++;
-
+
/* check mode */
if ((n - k) < 6) {
return;
}
-
+
if (memcmp(&src[k], "octet\0", 6) != 0) {
tftp_send_error(spt, 4, "Unsupported transfer mode", tp);
return;
}
+ k += 6; /* skipping octet */
+
/* do sanity checks on the filename */
if ((spt->filename[0] != '/')
- || (spt->filename[strlen(spt->filename) - 1] == '/')
- || strstr(spt->filename, "/../")) {
+ || (spt->filename[strlen((char *)spt->filename) - 1] == '/')
+ || strstr((char *)spt->filename, "/../")) {
tftp_send_error(spt, 2, "Access violation", tp);
return;
}
/* only allow exported prefixes */
- if (!tftp_prefix
- || (strncmp(spt->filename, tftp_prefix, strlen(tftp_prefix)) != 0)) {
+ if (!tftp_prefix) {
tftp_send_error(spt, 2, "Access violation", tp);
return;
}
/* check if the file exists */
-
+
if (tftp_read_data(spt, 0, spt->filename, 0) < 0) {
tftp_send_error(spt, 1, "File not found", tp);
return;
}
+ if (src[n - 1] != 0) {
+ tftp_send_error(spt, 2, "Access violation", tp);
+ return;
+ }
+
+ while (k < n) {
+ const char *key, *value;
+
+ key = (char *)src + k;
+ k += strlen(key) + 1;
+
+ if (k >= n) {
+ tftp_send_error(spt, 2, "Access violation", tp);
+ return;
+ }
+
+ value = (char *)src + k;
+ k += strlen(value) + 1;
+
+ if (strcmp(key, "tsize") == 0) {
+ int tsize = atoi(value);
+ struct stat stat_p;
+
+ if (tsize == 0 && tftp_prefix) {
+ char buffer[1024];
+ int len;
+
+ len = snprintf(buffer, sizeof(buffer), "%s/%s",
+ tftp_prefix, spt->filename);
+
+ if (stat(buffer, &stat_p) == 0)
+ tsize = stat_p.st_size;
+ else {
+ tftp_send_error(spt, 1, "File not found", tp);
+ return;
+ }
+ }
+
+ tftp_send_oack(spt, "tsize", tsize, tp);
+ }
+ }
+
tftp_send_data(spt, 1, tp);
}
return;
}
- if (tftp_send_data(&tftp_sessions[s],
- ntohs(tp->x.tp_data.tp_block_nr) + 1,
+ if (tftp_send_data(&tftp_sessions[s],
+ ntohs(tp->x.tp_data.tp_block_nr) + 1,
tp) < 0) {
return;
}
projects / mirror_qemu.git / blobdiff