-/*************************************************
-* SMTP command read timeout *
-*************************************************/
-
-/* Signal handler for timing out incoming SMTP commands. This attempts to
-finish off tidily.
-
-Argument: signal number (SIGALRM)
-Returns: nothing
-*/
-
-static void
-command_timeout_handler(int sig)
-{
-had_command_timeout = sig;
-}
-
-
-
-/*************************************************
-* SIGTERM received *
-*************************************************/
-
-/* Signal handler for handling SIGTERM. Again, try to finish tidily.
-
-Argument: signal number (SIGTERM)
-Returns: nothing
-*/
-
-static void
-command_sigterm_handler(int sig)
-{
-had_command_sigterm = sig;
-}
-
-
-
-
-#ifdef SUPPORT_PROXY
-/*************************************************
-* Check if host is required proxy host *
-*************************************************/
-/* The function determines if inbound host will be a regular smtp host
-or if it is configured that it must use Proxy Protocol. A local
-connection cannot.
-
-Arguments: none
-Returns: bool
-*/
-
-static BOOL
-check_proxy_protocol_host()
-{
-int rc;
-
-if ( sender_host_address
- && (rc = verify_check_this_host(CUSS &hosts_proxy, NULL, NULL,
- sender_host_address, NULL)) == OK)
- {
- DEBUG(D_receive)
- debug_printf("Detected proxy protocol configured host\n");
- proxy_session = TRUE;
- }
-return proxy_session;
-}
-
-
-/*************************************************
-* Read data until newline or end of buffer *
-*************************************************/
-/* While SMTP is server-speaks-first, TLS is client-speaks-first, so we can't
-read an entire buffer and assume there will be nothing past a proxy protocol
-header. Our approach normally is to use stdio, but again that relies upon
-"STARTTLS\r\n" and a server response before the client starts TLS handshake, or
-reading _nothing_ before client TLS handshake. So we don't want to use the
-usual buffering reads which may read enough to block TLS starting.
-
-So unfortunately we're down to "read one byte at a time, with a syscall each,
-and expect a little overhead", for all proxy-opened connections which are v1,
-just to handle the TLS-on-connect case. Since SSL functions wrap the
-underlying fd, we can't assume that we can feed them any already-read content.
-
-We need to know where to read to, the max capacity, and we'll read until we
-get a CR and one more character. Let the caller scream if it's CR+!LF.
-
-Return the amount read.
-*/
-
-static int
-swallow_until_crlf(int fd, uschar *base, int already, int capacity)
-{
-uschar *to = base + already;
-uschar *cr;
-int have = 0;
-int ret;
-int last = 0;
-
-/* For "PROXY UNKNOWN\r\n" we, at time of writing, expect to have read
-up through the \r; for the _normal_ case, we haven't yet seen the \r. */
-
-cr = memchr(base, '\r', already);
-if (cr != NULL)
- {
- if ((cr - base) < already - 1)
- {
- /* \r and presumed \n already within what we have; probably not
- actually proxy protocol, but abort cleanly. */
- return 0;
- }
- /* \r is last character read, just need one more. */
- last = 1;
- }
-
-while (capacity > 0)
- {
- do { ret = read(fd, to, 1); } while (ret == -1 && errno == EINTR && !had_command_timeout);
- if (ret == -1)
- return -1;
- have++;
- if (last)
- return have;
- if (*to == '\r')
- last = 1;
- capacity--;
- to++;
- }
-
-/* reached end without having room for a final newline, abort */
-errno = EOVERFLOW;
-return -1;
-}
-
-/*************************************************
-* Setup host for proxy protocol *
-*************************************************/
-/* The function configures the connection based on a header from the
-inbound host to use Proxy Protocol. The specification is very exact
-so exit with an error if do not find the exact required pieces. This
-includes an incorrect number of spaces separating args.
-
-Arguments: none
-Returns: Boolean success
-*/
-
-static void
-setup_proxy_protocol_host()
-{
-union {
- struct {
- uschar line[108];
- } v1;
- struct {
- uschar sig[12];
- uint8_t ver_cmd;
- uint8_t fam;
- uint16_t len;
- union {
- struct { /* TCP/UDP over IPv4, len = 12 */
- uint32_t src_addr;
- uint32_t dst_addr;
- uint16_t src_port;
- uint16_t dst_port;
- } ip4;
- struct { /* TCP/UDP over IPv6, len = 36 */
- uint8_t src_addr[16];
- uint8_t dst_addr[16];
- uint16_t src_port;
- uint16_t dst_port;
- } ip6;
- struct { /* AF_UNIX sockets, len = 216 */
- uschar src_addr[108];
- uschar dst_addr[108];
- } unx;
- } addr;
- } v2;
-} hdr;
-
-/* Temp variables used in PPv2 address:port parsing */
-uint16_t tmpport;
-char tmpip[INET_ADDRSTRLEN];
-struct sockaddr_in tmpaddr;
-char tmpip6[INET6_ADDRSTRLEN];
-struct sockaddr_in6 tmpaddr6;
-
-/* We can't read "all data until end" because while SMTP is
-server-speaks-first, the TLS handshake is client-speaks-first, so for
-TLS-on-connect ports the proxy protocol header will usually be immediately
-followed by a TLS handshake, and with N TLS libraries, we can't reliably
-reinject data for reading by those. So instead we first read "enough to be
-safely read within the header, and figure out how much more to read".
-For v1 we will later read to the end-of-line, for v2 we will read based upon
-the stated length.
-
-The v2 sig is 12 octets, and another 4 gets us the length, so we know how much
-data is needed total. For v1, where the line looks like:
-PROXY TCPn L3src L3dest SrcPort DestPort \r\n
-
-However, for v1 there's also `PROXY UNKNOWN\r\n` which is only 15 octets.
-We seem to support that. So, if we read 14 octets then we can tell if we're
-v2 or v1. If we're v1, we can continue reading as normal.
-
-If we're v2, we can't slurp up the entire header. We need the length in the
-15th & 16th octets, then to read everything after that.
-
-So to safely handle v1 and v2, with client-sent-first supported correctly,
-we have to do a minimum of 3 read calls, not 1. Eww.
-*/
-
-#define PROXY_INITIAL_READ 14
-#define PROXY_V2_HEADER_SIZE 16
-#if PROXY_INITIAL_READ > PROXY_V2_HEADER_SIZE
-# error Code bug in sizes of data to read for proxy usage
-#endif
-
-int get_ok = 0;
-int size, ret;
-int fd = fileno(smtp_in);
-const char v2sig[12] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A";
-uschar * iptype; /* To display debug info */
-socklen_t vslen = sizeof(struct timeval);
-BOOL yield = FALSE;
-
-os_non_restarting_signal(SIGALRM, command_timeout_handler);
-ALARM(proxy_protocol_timeout);
-
-do
- {
- /* The inbound host was declared to be a Proxy Protocol host, so
- don't do a PEEK into the data, actually slurp up enough to be
- "safe". Can't take it all because TLS-on-connect clients follow
- immediately with TLS handshake. */
- ret = read(fd, &hdr, PROXY_INITIAL_READ);
- }
- while (ret == -1 && errno == EINTR && !had_command_timeout);
-
-if (ret == -1)
- goto proxyfail;
-
-/* For v2, handle reading the length, and then the rest. */
-if ((ret == PROXY_INITIAL_READ) && (memcmp(&hdr.v2, v2sig, sizeof(v2sig)) == 0))
- {
- int retmore;
- uint8_t ver;
-
- /* First get the length fields. */
- do
- {
- retmore = read(fd, (uschar*)&hdr + ret, PROXY_V2_HEADER_SIZE - PROXY_INITIAL_READ);
- } while (retmore == -1 && errno == EINTR && !had_command_timeout);
- if (retmore == -1)
- goto proxyfail;
- ret += retmore;
-
- ver = (hdr.v2.ver_cmd & 0xf0) >> 4;