/* returns error if no retry_after hdr field is present */
static int blst_add_retry_after_f(struct sip_msg* msg, char* min, char* max)
{
#ifdef USE_DST_BLACKLIST
int t_min, t_max, t;
struct dest_info src;
struct hdr_field* hf;
if (likely(cfg_get(core, core_cfg, use_dst_blacklist))){
if (unlikely(get_int_fparam(&t_min, msg, (fparam_t*)min)<0)) return -1;
if (likely(max)){
if (unlikely(get_int_fparam(&t_max, msg, (fparam_t*)max)<0))
return -1;
}else{
t_max=0;
}
init_dest_info(&src);
src.send_sock=0;
src.to=msg->rcv.src_su;
src.id=msg->rcv.proto_reserved1;
src.proto=msg->rcv.proto;
t=-1;
if ((parse_headers(msg, HDR_RETRY_AFTER_F, 0)==0) &&
(msg->parsed_flag & HDR_RETRY_AFTER_F)){
for (hf=msg->headers; hf; hf=hf->next)
if (hf->type==HDR_RETRY_AFTER_T){
/* found */
t=(unsigned)(unsigned long)hf->parsed;
break;
}
}
if (t<0)
return -1;
t=MAX_unsigned(t, t_min);
t=MIN_unsigned(t, t_max);
if (likely(t))
dst_blacklist_force_add_to(BLST_ADM_PROHIBITED, &src, msg,
S_TO_TICKS(t));
return 1;
}else{
LOG(L_WARN, "WARNING: blst: blst_add_retry_after:"
" blacklist support disabled\n");
}
#else /* USE_DST_BLACKLIST */
LOG(L_WARN, "WARNING: blst: blst_add_retry_after:"
" blacklist support not compiled-in - no effect -\n");
#endif /* USE_DST_BLACKLIST */
return 1;
}
/** tls read.
* Each modification of ssl data structures has to be protected, another process * might ask for the same connection and attempt write to it which would
* result in updating the ssl structures.
* WARNING: must be called whic c->write_lock _unlocked_.
* @param c - tcp connection pointer. The following flags might be set:
* @param flags - value/result:
* input: RD_CONN_FORCE_EOF - force EOF after the first
* successful read (bytes_read >=0 )
* output: RD_CONN_SHORT_READ if the read exhausted
* all the bytes in the socket read buffer.
* RD_CONN_EOF if EOF detected (0 bytes read)
* or forced via RD_CONN_FORCE_EOF.
* RD_CONN_REPEAT_READ if this function should
* be called again (e.g. has some data
* buffered internally that didn't fit in
* tcp_req).
* Note: RD_CONN_SHORT_READ & RD_CONN_EOF should be cleared
* before calling this function when there is new
* data (e.g. POLLIN), but not if the called is
* retried because of RD_CONN_REPEAT_READ and there
* is no information about the socket having more
* read data available.
* @return bytes decrypted on success, -1 on error (it also sets some
* tcp connection flags and might set c->state and r->error on
* EOF or error).
*/
int tls_read_f(struct tcp_connection* c, int* flags)
{
struct tcp_req* r;
int bytes_free, bytes_read, read_size, ssl_error, ssl_read;
SSL* ssl;
unsigned char rd_buf[TLS_RD_MBUF_SZ];
unsigned char wr_buf[TLS_WR_MBUF_SZ];
struct tls_mbuf rd, wr;
struct tls_extra_data* tls_c;
struct tls_rd_buf* enc_rd_buf;
int n, flush_flags;
char* err_src;
int x;
int tls_dbg;
TLS_RD_TRACE("(%p, %p (%d)) start (%s -> %s:%d*)\n",
c, flags, *flags,
su2a(&c->rcv.src_su, sizeof(c->rcv.src_su)),
ip_addr2a(&c->rcv.dst_ip), c->rcv.dst_port);
ssl_read = 0;
r = &c->req;
enc_rd_buf = 0;
*flags &= ~RD_CONN_REPEAT_READ;
if (unlikely(tls_fix_connection(c) < 0)) {
TLS_RD_TRACE("(%p, %p) end: tls_fix_connection failed =>"
" immediate error exit\n", c, flags);
return -1;
}
/* here it's safe to use c->extra_data in read-only mode.
If it's != 0 is changed only on destroy. It's not possible to have
parallel reads.*/
tls_c = c->extra_data;
bytes_free = c->req.b_size - (int)(r->pos - r->buf);
if (unlikely(bytes_free == 0)) {
ERR("Buffer overrun, dropping\n");
r->error = TCP_REQ_OVERRUN;
return -1;
}
redo_read:
/* if data queued from a previous read(), use it (don't perform
* a real read()).
*/
if (unlikely(tls_c->enc_rd_buf)) {
/* use queued data */
/* safe to use without locks, because only read changes it and
there can't be parallel reads on the same connection */
enc_rd_buf = tls_c->enc_rd_buf;
tls_c->enc_rd_buf = 0;
TLS_RD_TRACE("(%p, %p) using queued data (%p: %p %d bytes)\n", c,
flags, enc_rd_buf, enc_rd_buf->buf + enc_rd_buf->pos,
enc_rd_buf->size - enc_rd_buf->pos);
tls_mbuf_init(&rd, enc_rd_buf->buf + enc_rd_buf->pos,
enc_rd_buf->size - enc_rd_buf->pos);
rd.used = enc_rd_buf->size - enc_rd_buf->pos;
} else {
/* if we were using using queued data before, free & reset the
the queued read data before performing the real read() */
if (unlikely(enc_rd_buf)) {
TLS_RD_TRACE("(%p, %p) reset prev. used enc_rd_buf (%p)\n", c,
flags, enc_rd_buf);
shm_free(enc_rd_buf);
enc_rd_buf = 0;
}
/* real read() */
tls_mbuf_init(&rd, rd_buf, sizeof(rd_buf));
/* read() only if no previously detected EOF, or previous
short read (which means the socket buffer was emptied) */
if (likely(!(*flags & (RD_CONN_EOF|RD_CONN_SHORT_READ)))) {
/* don't read more then the free bytes in the tcp req buffer */
read_size = MIN_unsigned(rd.size, bytes_free);
bytes_read = tcp_read_data(c->fd, c, (char*)rd.buf, read_size,
flags);
TLS_RD_TRACE("(%p, %p) tcp_read_data(..., %d, *%d) => %d bytes\n",
c, flags, read_size, *flags, bytes_read);
/* try SSL_read even on 0 bytes read, it might have
internally buffered data */
if (unlikely(bytes_read < 0)) {
goto error;
}
rd.used = bytes_read;
}
}
continue_ssl_read:
tls_mbuf_init(&wr, wr_buf, sizeof(wr_buf));
ssl_error = SSL_ERROR_NONE;
err_src = "TLS read:";
/* we have to avoid to run in the same time
* with a tls_write because of the
* update bio stuff (we don't want a write
* stealing the wbio or rbio under us or vice versa)
* => lock on con->write_lock (ugly hack) */
lock_get(&c->write_lock);
tls_set_mbufs(c, &rd, &wr);
ssl = tls_c->ssl;
n = 0;
if (unlikely(tls_write_wants_read(tls_c) &&
!(*flags & RD_CONN_EOF))) {
n = tls_ct_wq_flush(c, &tls_c->ct_wq, &flush_flags,
&ssl_error);
TLS_RD_TRACE("(%p, %p) tls write on read (WRITE_WANTS_READ):"
" ct_wq_flush()=> %d (ff=%d ssl_error=%d))\n",
c, flags, n, flush_flags, ssl_error);
if (unlikely(n < 0 )) {
tls_set_mbufs(c, 0, 0);
lock_release(&c->write_lock);
ERR("write flush error (%d)\n", n);
goto error;
}
if (likely(flush_flags & F_BUFQ_EMPTY))
tls_c->flags &= ~F_TLS_CON_WR_WANTS_RD;
if (unlikely(flush_flags & F_BUFQ_ERROR_FLUSH))
err_src = "TLS write:";
}
if (likely(ssl_error == SSL_ERROR_NONE)) {
if (unlikely(tls_c->state == S_TLS_CONNECTING)) {
n = tls_connect(c, &ssl_error);
TLS_RD_TRACE("(%p, %p) tls_connect() => %d (err=%d)\n",
c, flags, n, ssl_error);
if (unlikely(n>=1)) {
n = SSL_read(ssl, r->pos, bytes_free);
} else {
/* tls_connect failed/needs more IO */
if (unlikely(n < 0 && ssl_error == SSL_ERROR_NONE)) {
lock_release(&c->write_lock);
goto error;
}
err_src = "TLS connect:";
goto ssl_read_skipped;
}
} else if (unlikely(tls_c->state == S_TLS_ACCEPTING)) {
n = tls_accept(c, &ssl_error);
TLS_RD_TRACE("(%p, %p) tls_accept() => %d (err=%d)\n",
c, flags, n, ssl_error);
if (unlikely(n>=1)) {
n = SSL_read(ssl, r->pos, bytes_free);
} else {
/* tls_accept failed/needs more IO */
if (unlikely(n < 0 && ssl_error == SSL_ERROR_NONE)) {
lock_release(&c->write_lock);
goto error;
}
err_src = "TLS accept:";
goto ssl_read_skipped;
}
} else {
/* if bytes in then decrypt read buffer into tcpconn req.
buffer */
n = SSL_read(ssl, r->pos, bytes_free);
}
/** handle SSL_read() return.
* There are 3 main cases, each with several sub-cases, depending
* on whether or not the output buffer was filled, if there
* is still unconsumed input data in the input buffer (rd)
* and if there is "cached" data in the internal openssl
* buffers.
* 0. error (n<=0):
* SSL_ERROR_WANT_READ - input data fully
* consumed, no more returnable cached data inside openssl
* => exit.
* SSL_ERROR_WANT_WRITE - should never happen (the write
* buffer is big enough to handle any re-negociation).
* SSL_ERROR_ZERO_RETURN - ssl level shutdown => exit.
* other errors are unexpected.
* 1. output buffer filled (n == bytes_free):
* 1i. - still unconsumed input, nothing buffered by openssl
* 1ip. - unconsumed input + buffered data by openssl (pending
on the next SSL_read).
* 1p. - completely consumed input, buffered data internally
* by openssl (pending).
* Likely to happen, about the only case when
* SSL_pending() could be used (but only if readahead=0).
* 1f. - consumed input, no buffered data.
* 2. output buffer not fully filled (n < bytes_free):
* 2i. - still unconsumed input, nothing buffered by openssl.
* This can appear if SSL readahead is 0 (SSL_read()
* tries to get only 1 record from the input).
* 2ip. - unconsumed input and buffered data by openssl.
* Unlikely to happen (e.g. readahead is 1, more
* records are buffered internally by openssl, but
* there was not enough space for buffering the whole
* input).
* 2p - consumed input, but buffered data by openssl.
* It happens especially when readahead is 1.
* 2f. - consumed input, no buffered data.
*
* One should repeat SSL_read() until and error is detected
* (0*) or the input and internal ssl buffers are fully consumed
* (1f or 2f). However in general is not possible to see if
* SSL_read() could return more data. SSL_pending() has very
* limited usability (basically it would return !=0 only if there
* was no enough space in the output buffer and only if this did
* not happen at a record boundary).
* The solution is to repeat SSL_read() until error or until
* the output buffer is filled (0* or 1*).
* In the later case, this whole function should be called again
* once there is more output space (set RD_CONN_REPEAT_READ).
*/
if (unlikely(tls_c->flags & F_TLS_CON_RENEGOTIATION)) {
/* Fix CVE-2009-3555 - disable renegotiation if started by client
* - simulate SSL EOF to force close connection*/
tls_dbg = cfg_get(tls, tls_cfg, debug);
LOG(tls_dbg, "Reading on a renegotiation of connection (n:%d) (%d)\n",
n, SSL_get_error(ssl, n));
err_src = "TLS R-N read:";
ssl_error = SSL_ERROR_ZERO_RETURN;
} else {
if (unlikely(n <= 0)) {
ssl_error = SSL_get_error(ssl, n);
err_src = "TLS read:";
/* errors handled below, outside the lock */
} else {
ssl_error = SSL_ERROR_NONE;
r->pos += n;
ssl_read += n;
bytes_free -=n;
}
}
TLS_RD_TRACE("(%p, %p) SSL_read() => %d (err=%d) ssl_read=%d"
" *flags=%d tls_c->flags=%d\n",
c, flags, n, ssl_error, ssl_read, *flags,
tls_c->flags);
ssl_read_skipped:
;
}
if (unlikely(wr.used != 0 && ssl_error != SSL_ERROR_ZERO_RETURN)) {
TLS_RD_TRACE("(%p, %p) tcpconn_send_unsafe %d bytes\n",
c, flags, wr.used);
/* something was written and it's not ssl EOF*/
if (unlikely(tcpconn_send_unsafe(c->fd, c, (char*)wr.buf,
wr.used, c->send_flags) < 0)) {
tls_set_mbufs(c, 0, 0);
lock_release(&c->write_lock);
TLS_RD_TRACE("(%p, %p) tcpconn_send_unsafe error\n", c, flags);
goto error_send;
}
}
/* quickly catch bugs: segfault if accessed and not set */
tls_set_mbufs(c, 0, 0);
lock_release(&c->write_lock);
switch(ssl_error) {
case SSL_ERROR_NONE:
if (unlikely(n < 0)) {
BUG("unexpected SSL_ERROR_NONE for n=%d\n", n);
goto error;
}
break;
case SSL_ERROR_ZERO_RETURN:
/* SSL EOF */
TLS_RD_TRACE("(%p, %p) SSL EOF (fd=%d)\n", c, flags, c->fd);
goto ssl_eof;
case SSL_ERROR_WANT_READ:
TLS_RD_TRACE("(%p, %p) SSL_ERROR_WANT_READ *flags=%d\n",
c, flags, *flags);
/* needs to read more data */
if (unlikely(rd.pos != rd.used)) {
/* data still in the read buffer */
BUG("SSL_ERROR_WANT_READ but data still in"
" the rbio (%p, %d bytes at %d)\n", rd.buf,
rd.used - rd.pos, rd.pos);
goto bug;
}
if (unlikely((*flags & (RD_CONN_EOF | RD_CONN_SHORT_READ)) == 0) &&
bytes_free){
/* there might still be data to read and there is space
to decrypt it in tcp_req (no byte has been written into
tcp_req in this case) */
TLS_RD_TRACE("(%p, %p) redo read *flags=%d bytes_free=%d\n",
c, flags, *flags, bytes_free);
goto redo_read;
}
goto end; /* no more data to read */
case SSL_ERROR_WANT_WRITE:
if (wr.used) {
/* something was written => buffer not big enough to hold
everything => reset buffer & retry (the tcp_write already
happened if we are here) */
TLS_RD_TRACE("(%p) SSL_ERROR_WANT_WRITE partial write"
" (written %d), retrying\n", c, wr.used);
goto continue_ssl_read;
}
/* else write buffer too small, nothing written */
BUG("write buffer too small (%d/%d bytes)\n",
wr.used, wr.size);
goto bug;
case SSL_ERROR_SSL:
/* protocol level error */
TLS_ERR(err_src);
goto error;
#if OPENSSL_VERSION_NUMBER >= 0x00907000L /*0.9.7*/
case SSL_ERROR_WANT_CONNECT:
/* only if the underlying BIO is not yet connected
and the call would block in connect().
(not possible in our case) */
BUG("unexpected SSL_ERROR_WANT_CONNECT\n");
goto bug;
case SSL_ERROR_WANT_ACCEPT:
/* only if the underlying BIO is not yet connected
and call would block in accept()
(not possible in our case) */
BUG("unexpected SSL_ERROR_WANT_ACCEPT\n");
goto bug;
#endif
case SSL_ERROR_WANT_X509_LOOKUP:
/* can only appear on client application and it indicates that
an installed client cert. callback should be called again
(it returned < 0 indicated that it wants to be called
later). Not possible in our case */
BUG("unsupported SSL_ERROR_WANT_X509_LOOKUP");
goto bug;
case SSL_ERROR_SYSCALL:
TLS_ERR_RET(x, err_src);
if (!x) {
if (n == 0) {
WARN("Unexpected EOF\n");
} else
/* should never happen */
BUG("IO error (%d) %s\n", errno, strerror(errno));
}
goto error;
default:
TLS_ERR(err_src);
BUG("unexpected SSL error %d\n", ssl_error);
goto bug;
}
if (unlikely(n < 0)) {
/* here n should always be >= 0 */
BUG("unexpected value (n = %d)\n", n);
goto bug;
}
if (unlikely(rd.pos != rd.used)) {
/* encrypted data still in the read buffer (SSL_read() did not
consume all of it) */
if (unlikely(n < 0))
/* here n should always be >= 0 */
BUG("unexpected value (n = %d)\n", n);
else {
if (unlikely(bytes_free != 0)) {
/* 2i or 2ip: unconsumed input and output buffer not filled =>
retry ssl read (SSL_read() will read will stop at
record boundaries, unless readahead==1).
No tcp_read() is attempted, since that would reset the
current no-yet-consumed input data.
*/
TLS_RD_TRACE("(%p, %p) input not fully consumed =>"
" retry SSL_read"
" (pos: %d, remaining %d, output free %d)\n",
c, flags, rd.pos, rd.used-rd.pos, bytes_free);
goto continue_ssl_read;
}
/* 1i or 1ip: bytes_free == 0
(unconsumed input, but filled output buffer) =>
queue read data, and exit asking for repeating the call
once there is some space in the output buffer.
*/
if (likely(!enc_rd_buf)) {
TLS_RD_TRACE("(%p, %p) creating enc_rd_buf (for %d bytes)\n",
c, flags, rd.used - rd.pos);
enc_rd_buf = shm_malloc(sizeof(*enc_rd_buf) -
sizeof(enc_rd_buf->buf) +
rd.used - rd.pos);
if (unlikely(enc_rd_buf == 0)) {
ERR("memory allocation error (%d bytes requested)\n",
(int)(sizeof(*enc_rd_buf) + sizeof(enc_rd_buf->buf) +
rd.used - rd.pos));
goto error;
}
enc_rd_buf->pos = 0;
enc_rd_buf->size = rd.used - rd.pos;
memcpy(enc_rd_buf->buf, rd.buf + rd.pos,
enc_rd_buf->size);
} else if ((enc_rd_buf->buf + enc_rd_buf->pos) == rd.buf) {
TLS_RD_TRACE("(%p, %p) enc_rd_buf already in use,"
" updating pos %d\n",
c, flags, enc_rd_buf->pos);
enc_rd_buf->pos += rd.pos;
} else {
BUG("enc_rd_buf->buf = %p, pos = %d, rd_buf.buf = %p\n",
enc_rd_buf->buf, enc_rd_buf->pos, rd.buf);
goto bug;
}
if (unlikely(tls_c->enc_rd_buf))
BUG("tls_c->enc_rd_buf!=0 (%p)\n", tls_c->enc_rd_buf);
/* there can't be 2 reads in parallel, so no locking is needed
here */
tls_c->enc_rd_buf = enc_rd_buf;
enc_rd_buf = 0;
*flags |= RD_CONN_REPEAT_READ;
}
} else if (bytes_free != 0) {
/* 2f or 2p: input fully consumed (rd.pos == rd.used),
output buffer not filled, still possible to have pending
data buffered by openssl */
if (unlikely((*flags & (RD_CONN_EOF|RD_CONN_SHORT_READ)) == 0)) {
/* still space in the tcp unenc. req. buffer, no SSL_read error,
not a short read and not an EOF (possible more data in
the socket buffer) => try a new tcp read too */
TLS_RD_TRACE("(%p, %p) retry read (still space and no short"
" tcp read: %d)\n", c, flags, *flags);
goto redo_read;
} else {
/* don't tcp_read() anymore, but there might still be data
buffered internally by openssl (e.g. if readahead==1) =>
retry SSL_read() with the current full input buffer
(if no more internally SSL buffered data => WANT_READ => exit).
*/
TLS_RD_TRACE("(%p, %p) retry SSL_read only (*flags =%d)\n",
c, flags, *flags);
goto continue_ssl_read;
}
} else {
/* 1p or 1f: rd.pos == rd.used && bytes_free == 0
(input fully consumed && output buffer filled) */
/* ask for a repeat when there is more buffer space
(there is no definitive way to know if ssl doesn't still have
some internal buffered data until we get WANT_READ, see
SSL_read() comment above) */
*flags |= RD_CONN_REPEAT_READ;
TLS_RD_TRACE("(%p, %p) output filled, exit asking to be called again"
" (*flags =%d)\n", c, flags, *flags);
}
end:
if (enc_rd_buf)
shm_free(enc_rd_buf);
TLS_RD_TRACE("(%p, %p) end => %d (*flags=%d)\n",
c, flags, ssl_read, *flags);
return ssl_read;
ssl_eof:
/* behave as an EOF would have been received at the tcp level */
if (enc_rd_buf)
shm_free(enc_rd_buf);
c->state = S_CONN_EOF;
*flags |= RD_CONN_EOF;
TLS_RD_TRACE("(%p, %p) end EOF => %d (*flags=%d)\n",
c, flags, ssl_read, *flags);
return ssl_read;
error_send:
error:
bug:
if (enc_rd_buf)
shm_free(enc_rd_buf);
r->error=TCP_READ_ERROR;
TLS_RD_TRACE("(%p, %p) end error => %d (*flags=%d)\n",
c, flags, ssl_read, *flags);
return -1;
}
