* Exim - an Internet mail transport agent *
*************************************************/
+/* Copyright (c) The Exim Maintainers 2020 - 2023 */
/* Copyright (c) University of Cambridge 1995 - 2018 */
-/* Copyright (c) The Exim Maintainers 2020 - 2021 */
/* See the file NOTICE for conditions of use and distribution. */
+/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Functions for finding hosts, either by gethostbyname(), gethostbyaddr(), or
directly via the DNS. When IPv6 is supported, getipnodebyname() and
if (limit < 1)
return 0;
if (random_seed == 0)
- {
- if (f.running_in_test_harness) random_seed = 42; else
+ if (f.running_in_test_harness)
+ random_seed = 42;
+ else
{
int p = (int)getpid();
random_seed = (int)time(NULL) ^ ((p << 16) | p);
}
- }
random_seed = 1103515245 * random_seed + 12345;
return (unsigned int)(random_seed >> 16) % limit;
}
}
-
-
-
-/*************************************************
-* Extract port from address string *
-*************************************************/
-
-/* In the spool file, and in the -oMa and -oMi options, a host plus port is
-given as an IP address followed by a dot and a port number. This function
-decodes this.
-
-An alternative format for the -oMa and -oMi options is [ip address]:port which
-is what Exim 4 uses for output, because it seems to becoming commonly used,
-whereas the dot form confuses some programs/people. So we recognize that form
-too.
-
-Argument:
- address points to the string; if there is a port, the '.' in the string
- is overwritten with zero to terminate the address; if the string
- is in the [xxx]:ppp format, the address is shifted left and the
- brackets are removed
-
-Returns: 0 if there is no port, else the port number. If there's a syntax
- error, leave the incoming address alone, and return 0.
-*/
-
-int
-host_address_extract_port(uschar *address)
-{
-int port = 0;
-uschar *endptr;
-
-/* Handle the "bracketed with colon on the end" format */
-
-if (*address == '[')
- {
- uschar *rb = address + 1;
- while (*rb != 0 && *rb != ']') rb++;
- if (*rb++ == 0) return 0; /* Missing ]; leave invalid address */
- if (*rb == ':')
- {
- port = Ustrtol(rb + 1, &endptr, 10);
- if (*endptr != 0) return 0; /* Invalid port; leave invalid address */
- }
- else if (*rb != 0) return 0; /* Bad syntax; leave invalid address */
- memmove(address, address + 1, rb - address - 2);
- rb[-2] = 0;
- }
-
-/* Handle the "dot on the end" format */
-
-else
- {
- int skip = -3; /* Skip 3 dots in IPv4 addresses */
- address--;
- while (*(++address) != 0)
- {
- int ch = *address;
- if (ch == ':') skip = 0; /* Skip 0 dots in IPv6 addresses */
- else if (ch == '.' && skip++ >= 0) break;
- }
- if (*address == 0) return 0;
- port = Ustrtol(address + 1, &endptr, 10);
- if (*endptr != 0) return 0; /* Invalid port; leave invalid address */
- *address = 0;
- }
-
-return port;
-}
-
-
/*************************************************
* Get port from a host item's name *
*************************************************/
ident set, no host => U=ident
ident set, host set => H=sender_fullhost U=ident
-Use taint-unchecked routines on the assumption we'll never expand the results.
-
Arguments:
useflag TRUE if first item to be flagged (H= or U=); if there are two
items, the second is always flagged
-Returns: pointer to a string in big_buffer
+Returns: pointer to an allocated string
*/
uschar *
host_and_ident(BOOL useflag)
{
+gstring * g = NULL;
+
if (!sender_fullhost)
- string_format_nt(big_buffer, big_buffer_size, "%s%s", useflag ? "U=" : "",
- sender_ident ? sender_ident : US"unknown");
+ {
+ if (useflag)
+ g = string_catn(g, US"U=", 2);
+ g = string_cat(g, sender_ident ? sender_ident : US"unknown");
+ }
else
{
- uschar * flag = useflag ? US"H=" : US"";
- uschar * iface = US"";
+ if (useflag)
+ g = string_catn(g, US"H=", 2);
+ g = string_cat(g, sender_fullhost);
if (LOGGING(incoming_interface) && interface_address)
- iface = string_sprintf(" I=[%s]:%d", interface_address, interface_port);
+ g = string_fmt_append(g, " I=[%s]:%d", interface_address, interface_port);
if (sender_ident)
- string_format_nt(big_buffer, big_buffer_size, "%s%s%s U=%s",
- flag, sender_fullhost, iface, sender_ident);
- else
- string_format_nt(big_buffer, big_buffer_size, "%s%s%s",
- flag, sender_fullhost, iface);
+ g = string_fmt_append(g, " U=%s", sender_ident);
}
-return big_buffer;
+if (LOGGING(connection_id))
+ g = string_fmt_append(g, " Ci=%lu", connection_id);
+gstring_release_unused(g);
+return string_from_gstring(g);
}
#endif /* STAND_ALONE */
*/
uschar *
-host_ntoa(int type, const void *arg, uschar *buffer, int *portptr)
+host_ntoa(int type, const void * arg, uschar * buffer, int * portptr)
{
-uschar *yield;
+uschar * yield;
/* The new world. It is annoying that we have to fish out the address from
different places in the block, depending on what kind of address it is. It
*/
int
-host_aton(const uschar *address, int *bin)
+host_aton(const uschar * address, int * bin)
{
int x[4];
int v4offset = 0;
if (Ustrchr(address, ':') != NULL)
{
- const uschar *p = address;
- const uschar *component[8];
+ const uschar * p = address;
+ const uschar * component[8];
BOOL ipv4_ends = FALSE;
- int ci = 0;
- int nulloffset = 0;
- int v6count = 8;
- int i;
+ int ci = 0, nulloffset = 0, v6count = 8, i;
/* If the address starts with a colon, it will start with two colons.
Just lose the first one, which will leave a null first component. */
overlooked; to guard against that happening again, check here and crash if
there are too many components. */
- while (*p != 0 && *p != '%')
+ while (*p && *p != '%')
{
int len = Ustrcspn(p, ":%");
if (len == 0) nulloffset = ci;
rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) if (rr->type == T_PTR)
{
uschar * s = store_get(ssize, GET_TAINTED); /* names are tainted */
+ unsigned slen;
/* If an overlong response was received, the data will have been
truncated and dn_expand may fail. */
break;
}
- store_release_above(s + Ustrlen(s) + 1);
- if (!s[0])
+ store_release_above(s + (slen = Ustrlen(s)) + 1);
+ if (!*s)
{
HDEBUG(D_host_lookup) debug_printf("IP address lookup yielded an "
"empty name: treated as non-existent host name\n");
continue;
}
+ if (Ustrspn(s, letter_digit_hyphen_dot) != slen)
+ {
+ HDEBUG(D_host_lookup) debug_printf("IP address lookup yielded an "
+ "illegal name (bad char): treated as non-existent host name\n");
+ continue;
+ }
if (!sender_host_name) sender_host_name = s;
else *aptr++ = s;
while (*s) { *s = tolower(*s); s++; }
if (!host->address)
{
uschar *msg =
- #ifndef STAND_ALONE
+#ifndef STAND_ALONE
!message_id[0] && smtp_in
? string_sprintf("no IP address found for host %s (during %s)", host->name,
smtp_get_connection_info()) :
- #endif
+#endif
string_sprintf("no IP address found for host %s", host->name);
HDEBUG(D_host_lookup) debug_printf("%s\n", msg);
const uschar * s = rr->data; /* MUST be unsigned for GETSHORT */
uschar data[256];
+ if (rr_bad_size(rr, sizeof(uint16_t))) continue;
GETSHORT(precedence, s); /* Pointer s is advanced */
/* For MX records, we use a random "weight" which causes multiple records of
/* SRV records are specified with a port and a weight. The weight is used
in a special algorithm. However, to start with, we just use it to order the
records of equal priority (precedence). */
+
+ if (rr_bad_increment(rr, s, 2 * sizeof(uint16_t))) continue;
GETSHORT(weight, s);
GETSHORT(port, s);
}