aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorkpfleming <kpfleming@f38db490-d61c-443f-a65b-d21fe96a405b>2006-06-05 19:53:16 +0000
committerkpfleming <kpfleming@f38db490-d61c-443f-a65b-d21fe96a405b>2006-06-05 19:53:16 +0000
commite11a0c0ed9616fca4f238a79ae3c140c31e1776d (patch)
tree7918149d368a5a1a538323712a8401894c6a05d2
parentfd3835d69af736fe96314979822eb5bd15e977f0 (diff)
ensure that the received number of bytes is included in all IAX2 incoming frame analysis checks (fixes a known vulnerability)
git-svn-id: http://svn.digium.com/svn/asterisk/branches/1.2@32373 f38db490-d61c-443f-a65b-d21fe96a405b
-rw-r--r--channels/chan_iax2.c63
1 files changed, 37 insertions, 26 deletions
diff --git a/channels/chan_iax2.c b/channels/chan_iax2.c
index d113a89ac..a7f0c2303 100644
--- a/channels/chan_iax2.c
+++ b/channels/chan_iax2.c
@@ -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