ensure that the received number of bytes is included in all IAX2 incoming frame analysis checks (fixes a known vulnerability)

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.2@32373 65c4cc65-6c06-0410-ace0-fbb531ad65f3
1.2
Kevin P. Fleming 19 years ago
parent 5684ba5966
commit c515ef705c

@ -6323,27 +6323,28 @@ static int socket_read(int *id, int fd, short events, void *cbdata)
return 1;
}
if (res < sizeof(struct ast_iax2_mini_hdr)) {
ast_log(LOG_WARNING, "midget packet received (%d of %d min)\n", res, (int)sizeof(struct ast_iax2_mini_hdr));
if (res < sizeof(*mh)) {
ast_log(LOG_WARNING, "midget packet received (%d of %zd min)\n", res, sizeof(*mh));
return 1;
}
if ((vh->zeros == 0) && (ntohs(vh->callno) & 0x8000)) {
if ((res >= sizeof(*vh)) && ((vh->zeros == 0) && (ntohs(vh->callno) & 0x8000))) {
/* This is a video frame, get call number */
fr->callno = find_callno(ntohs(vh->callno) & ~0x8000, dcallno, &sin, new, 1, fd);
minivid = 1;
} else if (meta->zeros == 0) {
} else if ((res >= sizeof(*meta)) && (meta->zeros == 0) && !(ntohs(meta->metacmd) & 0x8000)) {
unsigned char metatype;
/* This is a meta header */
switch(meta->metacmd) {
case IAX_META_TRUNK:
if (res < sizeof(struct ast_iax2_meta_hdr) + sizeof(struct ast_iax2_meta_trunk_hdr)) {
ast_log(LOG_WARNING, "midget meta trunk packet received (%d of %d min)\n", res, (int)sizeof(struct ast_iax2_mini_hdr));
if (res < (sizeof(*meta) + sizeof(*mth))) {
ast_log(LOG_WARNING, "midget meta trunk packet received (%d of %zd min)\n", res,
sizeof(*meta) + sizeof(*mth));
return 1;
}
mth = (struct ast_iax2_meta_trunk_hdr *)(meta->data);
ts = ntohl(mth->ts);
metatype = meta->cmddata;
res -= (sizeof(struct ast_iax2_meta_hdr) + sizeof(struct ast_iax2_meta_trunk_hdr));
res -= (sizeof(*meta) + sizeof(*mth));
ptr = mth->data;
tpeer = find_tpeer(&sin, fd);
if (!tpeer) {
@ -6355,21 +6356,21 @@ static int socket_read(int *id, int fd, short events, void *cbdata)
tpeer->rxtrunktime = tpeer->trunkact;
rxtrunktime = tpeer->rxtrunktime;
ast_mutex_unlock(&tpeer->lock);
while(res >= sizeof(struct ast_iax2_meta_trunk_entry)) {
while(res >= sizeof(*mte)) {
/* Process channels */
unsigned short callno, trunked_ts, len;
if(metatype == IAX_META_TRUNK_MINI) {
if (metatype == IAX_META_TRUNK_MINI) {
mtm = (struct ast_iax2_meta_trunk_mini *)ptr;
ptr += sizeof(struct ast_iax2_meta_trunk_mini);
res -= sizeof(struct ast_iax2_meta_trunk_mini);
ptr += sizeof(*mtm);
res -= sizeof(*mtm);
len = ntohs(mtm->len);
callno = ntohs(mtm->mini.callno);
trunked_ts = ntohs(mtm->mini.ts);
} else if ( metatype == IAX_META_TRUNK_SUPERMINI ) {
} else if (metatype == IAX_META_TRUNK_SUPERMINI) {
mte = (struct ast_iax2_meta_trunk_entry *)ptr;
ptr += sizeof(struct ast_iax2_meta_trunk_entry);
res -= sizeof(struct ast_iax2_meta_trunk_entry);
ptr += sizeof(*mte);
res -= sizeof(*mte);
len = ntohs(mte->len);
callno = ntohs(mte->callno);
trunked_ts = 0;
@ -6452,11 +6453,21 @@ static int socket_read(int *id, int fd, short events, void *cbdata)
}
return 1;
}
/* if we got here and ->zeros contains zeros, this cannot be a valid
miniframe or full frame but it wasn't a valid video frame or meta
frame either, so we reject it
*/
if (vh->zeros == 0) {
ast_log(LOG_WARNING, "Rejecting packet from '%s.%d' that is flagged as a video or meta frame but is not properly formatted\n", ast_inet_ntoa(iabuf, sizeof(iabuf), sin.sin_addr), ntohs(sin.sin_port));
return 1;
}
#ifdef DEBUG_SUPPORT
if (iaxdebug)
iax_showframe(NULL, fh, 1, &sin, res - sizeof(struct ast_iax2_full_hdr));
if (iaxdebug && (res >= sizeof(*fh)))
iax_showframe(NULL, fh, 1, &sin, res - sizeof(*fh));
#endif
if (ntohs(mh->callno) & IAX_FLAG_FULL) {
if ((res >= sizeof(*fh)) && ntohs(mh->callno) & IAX_FLAG_FULL) {
/* Get the destination call number */
dcallno = ntohs(fh->dcallno) & ~IAX_FLAG_RETRANS;
/* Retrieve the type and subclass */
@ -6507,7 +6518,7 @@ static int socket_read(int *id, int fd, short events, void *cbdata)
}
#ifdef DEBUG_SUPPORT
else if (iaxdebug)
iax_showframe(NULL, fh, 3, &sin, res - sizeof(struct ast_iax2_full_hdr));
iax_showframe(NULL, fh, 3, &sin, res - sizeof(*fh));
#endif
}
@ -6592,12 +6603,12 @@ static int socket_read(int *id, int fd, short events, void *cbdata)
iaxs[fr->callno]->iseqno++;
}
/* A full frame */
if (res < sizeof(struct ast_iax2_full_hdr)) {
ast_log(LOG_WARNING, "midget packet received (%d of %d min)\n", res, (int)sizeof(struct ast_iax2_full_hdr));
if (res < sizeof(*fh)) {
ast_log(LOG_WARNING, "midget packet received (%d of %zd min)\n", res, sizeof(*fh));
ast_mutex_unlock(&iaxsl[fr->callno]);
return 1;
}
f.datalen = res - sizeof(struct ast_iax2_full_hdr);
f.datalen = res - sizeof(*fh);
/* Handle implicit ACKing unless this is an INVAL, and only if this is
from the real peer, not the transfer peer */
@ -6655,14 +6666,14 @@ static int socket_read(int *id, int fd, short events, void *cbdata)
if (f.datalen) {
if (f.frametype == AST_FRAME_IAX) {
if (iax_parse_ies(&ies, buf + sizeof(struct ast_iax2_full_hdr), f.datalen)) {
if (iax_parse_ies(&ies, buf + sizeof(*fh), f.datalen)) {
ast_log(LOG_WARNING, "Undecodable frame received from '%s'\n", ast_inet_ntoa(iabuf, sizeof(iabuf), sin.sin_addr));
ast_mutex_unlock(&iaxsl[fr->callno]);
return 1;
}
f.data = NULL;
} else
f.data = buf + sizeof(struct ast_iax2_full_hdr);
f.data = buf + sizeof(*fh);
} else {
if (f.frametype == AST_FRAME_IAX)
f.data = NULL;
@ -7540,9 +7551,9 @@ retryowner2:
ast_mutex_unlock(&iaxsl[fr->callno]);
return 1;
}
f.datalen = res - sizeof(struct ast_iax2_video_hdr);
f.datalen = res - sizeof(*vh);
if (f.datalen)
f.data = buf + sizeof(struct ast_iax2_video_hdr);
f.data = buf + sizeof(*vh);
else
f.data = NULL;
#ifdef IAXTESTS
@ -7569,7 +7580,7 @@ retryowner2:
return 1;
}
if (f.datalen)
f.data = buf + sizeof(struct ast_iax2_mini_hdr);
f.data = buf + sizeof(*mh);
else
f.data = NULL;
#ifdef IAXTESTS

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