static void smtpd_peer_hostaddr_to_sockaddr(SMTPD_STATE *state)
{
const char *myname = "smtpd_peer_hostaddr_to_sockaddr";
struct addrinfo *res;
int aierr;
if ((aierr = hostaddr_to_sockaddr(state->addr, state->port,
SOCK_STREAM, &res)) != 0)
msg_fatal("%s: cannot convert client address/port to string: %s",
myname, MAI_STRERROR(aierr));
if (res->ai_addrlen > sizeof(state->sockaddr))
msg_panic("%s: address length > struct sockaddr_storage", myname);
memcpy((void *) &(state->sockaddr), res->ai_addr, res->ai_addrlen);
state->sockaddr_len = res->ai_addrlen;
freeaddrinfo(res);
}
static void smtp_update_addr_list(DNS_RR **addr_list, const char *server_addr,
int session_count)
{
DNS_RR *addr;
DNS_RR *next;
int aierr;
struct addrinfo *res0;
if (*addr_list == 0)
return;
/*
* Truncate the address list if we are not going to use it anyway.
*/
if (session_count == var_smtp_mxsess_limit
|| session_count == var_smtp_mxaddr_limit) {
dns_rr_free(*addr_list);
*addr_list = 0;
return;
}
/*
* Convert server address to internal form, and look it up in the address
* list.
*
* XXX smtp_reuse_session() breaks if we remove two or more adjacent list
* elements but do not truncate the list to zero length.
*
* XXX Extend the SMTP_SESSION structure with sockaddr information so that
* we can avoid repeated string->binary transformations for the same
* address.
*/
if ((aierr = hostaddr_to_sockaddr(server_addr, (char *) 0, 0, &res0)) != 0) {
msg_warn("hostaddr_to_sockaddr %s: %s",
server_addr, MAI_STRERROR(aierr));
} else {
for (addr = *addr_list; addr; addr = next) {
next = addr->next;
if (DNS_RR_EQ_SA(addr, (struct sockaddr *) res0->ai_addr)) {
*addr_list = dns_rr_remove(*addr_list, addr);
break;
}
}
freeaddrinfo(res0);
}
}
static VSTRING *dnsblog_query(VSTRING *result, const char *dnsbl_domain,
const char *addr)
{
const char *myname = "dnsblog_query";
ARGV *octets;
int i;
struct addrinfo *res;
unsigned char *ipv6_addr;
int dns_status;
DNS_RR *addr_list;
DNS_RR *rr;
MAI_HOSTADDR_STR hostaddr;
if (msg_verbose)
msg_info("%s: addr %s dnsbl_domain %s",
myname, addr, dnsbl_domain);
VSTRING_RESET(query);
/*
* Reverse the client IPV6 address, represented as 32 hexadecimal
* nibbles. We use the binary address to avoid tricky code. Asking for an
* AAAA record makes no sense here. Just like with IPv4 we use the lookup
* result as a bit mask, not as an IP address.
*/
#ifdef HAS_IPV6
if (valid_ipv6_hostaddr(addr, DONT_GRIPE)) {
if (hostaddr_to_sockaddr(addr, (char *) 0, 0, &res) != 0
|| res->ai_family != PF_INET6)
msg_fatal("%s: unable to convert address %s", myname, addr);
ipv6_addr = (unsigned char *) &SOCK_ADDR_IN6_ADDR(res->ai_addr);
for (i = sizeof(SOCK_ADDR_IN6_ADDR(res->ai_addr)) - 1; i >= 0; i--)
vstring_sprintf_append(query, "%x.%x.",
ipv6_addr[i] & 0xf, ipv6_addr[i] >> 4);
freeaddrinfo(res);
} else
#endif
/*
* Reverse the client IPV4 address, represented as four decimal octet
* values. We use the textual address for convenience.
*/
{
static SMTP_SESSION *smtp_connect_addr(SMTP_ITERATOR *iter, DSN_BUF *why,
int sess_flags)
{
const char *myname = "smtp_connect_addr";
struct sockaddr_storage ss; /* remote */
struct sockaddr *sa = (struct sockaddr *) &ss;
SOCKADDR_SIZE salen = sizeof(ss);
MAI_HOSTADDR_STR hostaddr;
DNS_RR *addr = iter->rr;
unsigned port = iter->port;
int sock;
char *bind_addr;
char *bind_var;
dsb_reset(why); /* Paranoia */
/*
* Sanity checks.
*/
if (dns_rr_to_sa(addr, port, sa, &salen) != 0) {
msg_warn("%s: skip address type %s: %m",
myname, dns_strtype(addr->type));
dsb_simple(why, "4.4.0", "network address conversion failed: %m");
return (0);
}
/*
* Initialize.
*/
if ((sock = socket(sa->sa_family, SOCK_STREAM, 0)) < 0)
msg_fatal("%s: socket: %m", myname);
if (inet_windowsize > 0)
set_inet_windowsize(sock, inet_windowsize);
/*
* Allow the sysadmin to specify the source address, for example, as "-o
* smtp_bind_address=x.x.x.x" in the master.cf file.
*/
#ifdef HAS_IPV6
if (sa->sa_family == AF_INET6) {
bind_addr = var_smtp_bind_addr6;
bind_var = VAR_LMTP_SMTP(BIND_ADDR6);
} else
#endif
if (sa->sa_family == AF_INET) {
bind_addr = var_smtp_bind_addr;
bind_var = VAR_LMTP_SMTP(BIND_ADDR);
} else
bind_var = bind_addr = "";
if (*bind_addr) {
int aierr;
struct addrinfo *res0;
if ((aierr = hostaddr_to_sockaddr(bind_addr, (char *) 0, 0, &res0)) != 0)
msg_fatal("%s: bad %s parameter: %s: %s",
myname, bind_var, bind_addr, MAI_STRERROR(aierr));
if (bind(sock, res0->ai_addr, res0->ai_addrlen) < 0)
msg_warn("%s: bind %s: %m", myname, bind_addr);
else if (msg_verbose)
msg_info("%s: bind %s", myname, bind_addr);
freeaddrinfo(res0);
}
/*
* When running as a virtual host, bind to the virtual interface so that
* the mail appears to come from the "right" machine address.
*
* XXX The IPv6 patch expands the null host (as client endpoint) and uses
* the result as the loopback address list.
*/
else {
int count = 0;
struct sockaddr *own_addr = 0;
INET_ADDR_LIST *addr_list = own_inet_addr_list();
struct sockaddr_storage *s;
for (s = addr_list->addrs; s < addr_list->addrs + addr_list->used; s++) {
if (SOCK_ADDR_FAMILY(s) == sa->sa_family) {
if (count++ > 0)
break;
own_addr = SOCK_ADDR_PTR(s);
}
}
if (count == 1 && !sock_addr_in_loopback(own_addr)) {
if (bind(sock, own_addr, SOCK_ADDR_LEN(own_addr)) < 0) {
SOCKADDR_TO_HOSTADDR(own_addr, SOCK_ADDR_LEN(own_addr),
&hostaddr, (MAI_SERVPORT_STR *) 0, 0);
msg_warn("%s: bind %s: %m", myname, hostaddr.buf);
} else if (msg_verbose) {
SOCKADDR_TO_HOSTADDR(own_addr, SOCK_ADDR_LEN(own_addr),
&hostaddr, (MAI_SERVPORT_STR *) 0, 0);
msg_info("%s: bind %s", myname, hostaddr.buf);
}
}
}
/*
* Connect to the server.
*/
if (msg_verbose)
msg_info("%s: trying: %s[%s] port %d...",
myname, STR(iter->host), STR(iter->addr), ntohs(port));
return (smtp_connect_sock(sock, sa, salen, iter, why, sess_flags));
}
void smtpd_peer_init(SMTPD_STATE *state)
{
const char *myname = "smtpd_peer_init";
SOCKADDR_SIZE sa_length;
struct sockaddr *sa;
INET_PROTO_INFO *proto_info = inet_proto_info();
sa = (struct sockaddr *) & (state->sockaddr);
sa_length = sizeof(state->sockaddr);
/*
* Look up the peer address information.
*
* XXX If we make local endpoint (getsockname) information available to
* Milter applications as {if_name} and {if_addr}, then we also must be
* able to provide this via the XCLIENT command for Milter testing.
*
* XXX If we make local or remote port information available to policy
* servers or Milter applications, then we must also make this testable
* with the XCLIENT command, otherwise there will be confusion.
*
* XXX If we make local or remote port information available via logging,
* then we must also support these attributes with the XFORWARD command.
*
* XXX If support were to be added for Milter applications in down-stream
* MTAs, then consistency demands that we propagate a lot of Sendmail
* macro information via the XFORWARD command. Otherwise we could end up
* with a very confusing situation.
*/
if (getpeername(vstream_fileno(state->client), sa, &sa_length) >= 0) {
errno = 0;
}
/*
* If peer went away, give up.
*/
if (errno != 0 && errno != ENOTSOCK) {
state->name = mystrdup(CLIENT_NAME_UNKNOWN);
state->reverse_name = mystrdup(CLIENT_NAME_UNKNOWN);
state->addr = mystrdup(CLIENT_ADDR_UNKNOWN);
state->rfc_addr = mystrdup(CLIENT_ADDR_UNKNOWN);
state->addr_family = AF_UNSPEC;
state->name_status = SMTPD_PEER_CODE_PERM;
state->reverse_name_status = SMTPD_PEER_CODE_PERM;
state->port = mystrdup(CLIENT_PORT_UNKNOWN);
}
/*
* Convert the client address to printable address and hostname.
*
* XXX If we're given an IPv6 (or IPv4) connection from, e.g., inetd, while
* Postfix IPv6 (or IPv4) support is turned off, don't (skip to the final
* else clause, pretend the origin is localhost[127.0.0.1], and become an
* open relay).
*/
else if (errno == 0
&& (sa->sa_family == AF_INET
#ifdef AF_INET6
|| sa->sa_family == AF_INET6
#endif
)) {
MAI_HOSTNAME_STR client_name;
MAI_HOSTADDR_STR client_addr;
MAI_SERVPORT_STR client_port;
int aierr;
char *colonp;
/*
* Sanity check: we can't use sockets that we're not configured for.
*/
if (strchr((char *) proto_info->sa_family_list, sa->sa_family) == 0)
msg_fatal("cannot handle socket type %s with \"%s = %s\"",
#ifdef AF_INET6
sa->sa_family == AF_INET6 ? "AF_INET6" :
#endif
sa->sa_family == AF_INET ? "AF_INET" :
"other", VAR_INET_PROTOCOLS, var_inet_protocols);
/*
* Sorry, but there are some things that we just cannot do while
* connected to the network.
*/
if (geteuid() != var_owner_uid || getuid() != var_owner_uid) {
msg_error("incorrect SMTP server privileges: uid=%lu euid=%lu",
(unsigned long) getuid(), (unsigned long) geteuid());
msg_fatal("the Postfix SMTP server must run with $%s privileges",
VAR_MAIL_OWNER);
}
/*
* Convert the client address to printable form.
*/
if ((aierr = sockaddr_to_hostaddr(sa, sa_length, &client_addr,
&client_port, 0)) != 0)
msg_fatal("%s: cannot convert client address/port to string: %s",
myname, MAI_STRERROR(aierr));
state->port = mystrdup(client_port.buf);
/*
* XXX Strip off the IPv6 datalink suffix to avoid false alarms with
* strict address syntax checks.
*/
#ifdef HAS_IPV6
(void) split_at(client_addr.buf, '%');
#endif
/*
* We convert IPv4-in-IPv6 address to 'true' IPv4 address early on,
* but only if IPv4 support is enabled (why would anyone want to turn
* it off)? With IPv4 support enabled we have no need for the IPv6
* form in logging, hostname verification and access checks.
*/
#ifdef HAS_IPV6
if (sa->sa_family == AF_INET6) {
if (strchr((char *) proto_info->sa_family_list, AF_INET) != 0
&& IN6_IS_ADDR_V4MAPPED(&SOCK_ADDR_IN6_ADDR(sa))
&& (colonp = strrchr(client_addr.buf, ':')) != 0) {
struct addrinfo *res0;
if (msg_verbose > 1)
msg_info("%s: rewriting V4-mapped address \"%s\" to \"%s\"",
myname, client_addr.buf, colonp + 1);
state->addr = mystrdup(colonp + 1);
state->rfc_addr = mystrdup(colonp + 1);
state->addr_family = AF_INET;
aierr = hostaddr_to_sockaddr(state->addr, (char *) 0, 0, &res0);
if (aierr)
msg_fatal("%s: cannot convert %s from string to binary: %s",
myname, state->addr, MAI_STRERROR(aierr));
sa_length = res0->ai_addrlen;
if (sa_length > sizeof(state->sockaddr))
sa_length = sizeof(state->sockaddr);
memcpy((char *) sa, res0->ai_addr, sa_length);
freeaddrinfo(res0); /* 200412 */
}
/*
* Following RFC 2821 section 4.1.3, an IPv6 address literal gets
* a prefix of 'IPv6:'. We do this consistently for all IPv6
* addresses that that appear in headers or envelopes. The fact
* that valid_mailhost_addr() enforces the form helps of course.
* We use the form without IPV6: prefix when doing access
* control, or when accessing the connection cache.
*/
else {
state->addr = mystrdup(client_addr.buf);
state->rfc_addr =
concatenate(IPV6_COL, client_addr.buf, (char *) 0);
state->addr_family = sa->sa_family;
}
}
/*
* An IPv4 address is in dotted quad decimal form.
*/
else
#endif
{
state->addr = mystrdup(client_addr.buf);
state->rfc_addr = mystrdup(client_addr.buf);
state->addr_family = sa->sa_family;
}
/*
* Look up and sanity check the client hostname.
*
* It is unsafe to allow numeric hostnames, especially because there
* exists pressure to turn off the name->addr double check. In that
* case an attacker could trivally bypass access restrictions.
*
* sockaddr_to_hostname() already rejects malformed or numeric names.
*/
#define TEMP_AI_ERROR(e) \
((e) == EAI_AGAIN || (e) == EAI_MEMORY || (e) == EAI_SYSTEM)
#define REJECT_PEER_NAME(state, code) { \
myfree(state->name); \
state->name = mystrdup(CLIENT_NAME_UNKNOWN); \
state->name_status = code; \
}
if (var_smtpd_peername_lookup == 0) {
state->name = mystrdup(CLIENT_NAME_UNKNOWN);
state->reverse_name = mystrdup(CLIENT_NAME_UNKNOWN);
state->name_status = SMTPD_PEER_CODE_PERM;
state->reverse_name_status = SMTPD_PEER_CODE_PERM;
} else if ((aierr = sockaddr_to_hostname(sa, sa_length, &client_name,
(MAI_SERVNAME_STR *) 0, 0)) != 0) {
state->name = mystrdup(CLIENT_NAME_UNKNOWN);
state->reverse_name = mystrdup(CLIENT_NAME_UNKNOWN);
state->name_status = (TEMP_AI_ERROR(aierr) ?
SMTPD_PEER_CODE_TEMP : SMTPD_PEER_CODE_PERM);
state->reverse_name_status = (TEMP_AI_ERROR(aierr) ?
SMTPD_PEER_CODE_TEMP : SMTPD_PEER_CODE_PERM);
} else {
struct addrinfo *res0;
struct addrinfo *res;
state->name = mystrdup(client_name.buf);
state->reverse_name = mystrdup(client_name.buf);
state->name_status = SMTPD_PEER_CODE_OK;
state->reverse_name_status = SMTPD_PEER_CODE_OK;
/*
* Reject the hostname if it does not list the peer address.
* Without further validation or qualification, such information
* must not be allowed to enter the audit trail, as people would
* draw false conclusions.
*/
aierr = hostname_to_sockaddr_pf(state->name, state->addr_family,
(char *) 0, 0, &res0);
if (aierr) {
msg_warn("%s: hostname %s verification failed: %s",
state->addr, state->name, MAI_STRERROR(aierr));
REJECT_PEER_NAME(state, (TEMP_AI_ERROR(aierr) ?
SMTPD_PEER_CODE_TEMP : SMTPD_PEER_CODE_FORGED));
} else {
for (res = res0; /* void */ ; res = res->ai_next) {
if (res == 0) {
msg_warn("%s: address not listed for hostname %s",
state->addr, state->name);
REJECT_PEER_NAME(state, SMTPD_PEER_CODE_FORGED);
break;
}
if (strchr((char *) proto_info->sa_family_list, res->ai_family) == 0) {
msg_info("skipping address family %d for host %s",
res->ai_family, state->name);
continue;
}
if (sock_addr_cmp_addr(res->ai_addr, sa) == 0)
break; /* keep peer name */
}
freeaddrinfo(res0);
}
}
}
/*
* If it's not Internet, assume the client is local, and avoid using the
* naming service because that can hang when the machine is disconnected.
*/
else {
state->name = mystrdup("localhost");
state->reverse_name = mystrdup("localhost");
state->addr = mystrdup("127.0.0.1"); /* XXX bogus. */
state->rfc_addr = mystrdup("127.0.0.1");/* XXX bogus. */
state->addr_family = AF_UNSPEC;
state->name_status = SMTPD_PEER_CODE_OK;
state->reverse_name_status = SMTPD_PEER_CODE_OK;
state->port = mystrdup("0"); /* XXX bogus. */
}
/*
* Do the name[addr]:port formatting for pretty reports.
*/
state->namaddr = SMTPD_BUILD_NAMADDRPORT(state->name, state->addr,
state->port);
}
int resolve_local(const char *addr)
{
char *saved_addr = mystrdup(addr);
char *dest;
const char *bare_dest;
struct addrinfo *res0 = 0;
ssize_t len;
/*
* The optimizer will eliminate tests that always fail.
*/
#define RETURN(x) \
do { \
myfree(saved_addr); \
if (res0) \
freeaddrinfo(res0); \
return(x); \
} while (0)
if (resolve_local_list == 0)
resolve_local_init();
/*
* Strip one trailing dot but not dot-dot.
*
* XXX This should not be distributed all over the code. Problem is,
* addresses can enter the system via multiple paths: networks, local
* forward/alias/include files, even as the result of address rewriting.
*/
len = strlen(saved_addr);
if (len == 0)
RETURN(0);
if (saved_addr[len - 1] == '.')
saved_addr[--len] = 0;
if (len == 0 || saved_addr[len - 1] == '.')
RETURN(0);
/*
* Compare the destination against the list of destinations that we
* consider local.
*/
if (string_list_match(resolve_local_list, saved_addr))
RETURN(1);
if (resolve_local_list->error != 0)
RETURN(resolve_local_list->error);
/*
* Compare the destination against the list of interface addresses that
* we are supposed to listen on.
*
* The destination may be an IPv6 address literal that was buried somewhere
* inside a deeply recursively nested address. This information comes
* from an untrusted source, and Wietse is not confident that everyone's
* getaddrinfo() etc. implementation is sufficiently robust. The syntax
* is complex enough with null field compression and with IPv4-in-IPv6
* addresses that errors are likely.
*
* The solution below is ad-hoc. We neutralize the string as soon as we
* realize that its contents could be harmful. We neutralize the string
* here, instead of neutralizing it in every resolve_local() caller.
* That's because resolve_local knows how the address is going to be
* parsed and converted into binary form.
*
* There are several more structural solutions to this.
*
* - One solution is to disallow address literals. This is not as bad as it
* seems: I have never seen actual legitimate use of address literals.
*
* - Another solution is to label each string with a trustworthiness label
* and to expect that all Postfix infrastructure will exercise additional
* caution when given a string with untrusted content. This is not likely
* to happen.
*
* FIX 200501 IPv6 patch did not require "IPv6:" prefix in numerical
* addresses.
*/
dest = saved_addr;
if (*dest == '[' && dest[len - 1] == ']') {
dest++;
dest[len -= 2] = 0;
if ((bare_dest = valid_mailhost_addr(dest, DO_GRIPE)) != 0
&& hostaddr_to_sockaddr(bare_dest, (char *) 0, 0, &res0) == 0) {
if (own_inet_addr(res0->ai_addr) || proxy_inet_addr(res0->ai_addr))
RETURN(1);
}
}
/*
* Must be remote, or a syntax error.
*/
RETURN(0);
}
static int smtpd_peer_sockaddr_to_hostaddr(SMTPD_STATE *state)
{
const char *myname = "smtpd_peer_sockaddr_to_hostaddr";
struct sockaddr *sa = (struct sockaddr *) &(state->sockaddr);
SOCKADDR_SIZE sa_length = state->sockaddr_len;
/*
* XXX If we're given an IPv6 (or IPv4) connection from, e.g., inetd,
* while Postfix IPv6 (or IPv4) support is turned off, don't (skip to the
* final else clause, pretend the origin is localhost[127.0.0.1], and
* become an open relay).
*/
if (sa->sa_family == AF_INET
#ifdef AF_INET6
|| sa->sa_family == AF_INET6
#endif
) {
MAI_HOSTADDR_STR client_addr;
MAI_SERVPORT_STR client_port;
int aierr;
char *colonp;
/*
* Sanity check: we can't use sockets that we're not configured for.
*/
if (strchr((char *) proto_info->sa_family_list, sa->sa_family) == 0)
msg_fatal("cannot handle socket type %s with \"%s = %s\"",
#ifdef AF_INET6
sa->sa_family == AF_INET6 ? "AF_INET6" :
#endif
sa->sa_family == AF_INET ? "AF_INET" :
"other", VAR_INET_PROTOCOLS, var_inet_protocols);
/*
* Sorry, but there are some things that we just cannot do while
* connected to the network.
*/
if (geteuid() != var_owner_uid || getuid() != var_owner_uid) {
msg_error("incorrect SMTP server privileges: uid=%lu euid=%lu",
(unsigned long) getuid(), (unsigned long) geteuid());
msg_fatal("the Postfix SMTP server must run with $%s privileges",
VAR_MAIL_OWNER);
}
/*
* Convert the client address to printable form.
*/
if ((aierr = sockaddr_to_hostaddr(sa, sa_length, &client_addr,
&client_port, 0)) != 0)
msg_fatal("%s: cannot convert client address/port to string: %s",
myname, MAI_STRERROR(aierr));
state->port = mystrdup(client_port.buf);
/*
* XXX Require that the infrastructure strips off the IPv6 datalink
* suffix to avoid false alarms with strict address syntax checks.
*/
#ifdef HAS_IPV6
if (strchr(client_addr.buf, '%') != 0)
msg_panic("%s: address %s has datalink suffix",
myname, client_addr.buf);
#endif
/*
* We convert IPv4-in-IPv6 address to 'true' IPv4 address early on,
* but only if IPv4 support is enabled (why would anyone want to turn
* it off)? With IPv4 support enabled we have no need for the IPv6
* form in logging, hostname verification and access checks.
*/
#ifdef HAS_IPV6
if (sa->sa_family == AF_INET6) {
if (strchr((char *) proto_info->sa_family_list, AF_INET) != 0
&& IN6_IS_ADDR_V4MAPPED(&SOCK_ADDR_IN6_ADDR(sa))
&& (colonp = strrchr(client_addr.buf, ':')) != 0) {
struct addrinfo *res0;
if (msg_verbose > 1)
msg_info("%s: rewriting V4-mapped address \"%s\" to \"%s\"",
myname, client_addr.buf, colonp + 1);
state->addr = mystrdup(colonp + 1);
state->rfc_addr = mystrdup(colonp + 1);
state->addr_family = AF_INET;
aierr = hostaddr_to_sockaddr(state->addr, (char *) 0, 0, &res0);
if (aierr)
msg_fatal("%s: cannot convert %s from string to binary: %s",
myname, state->addr, MAI_STRERROR(aierr));
sa_length = res0->ai_addrlen;
if (sa_length > sizeof(state->sockaddr))
sa_length = sizeof(state->sockaddr);
memcpy((void *) sa, res0->ai_addr, sa_length);
freeaddrinfo(res0); /* 200412 */
}
/*
* Following RFC 2821 section 4.1.3, an IPv6 address literal gets
* a prefix of 'IPv6:'. We do this consistently for all IPv6
* addresses that that appear in headers or envelopes. The fact
* that valid_mailhost_addr() enforces the form helps of course.
* We use the form without IPV6: prefix when doing access
* control, or when accessing the connection cache.
*/
else {
state->addr = mystrdup(client_addr.buf);
state->rfc_addr =
concatenate(IPV6_COL, client_addr.buf, (char *) 0);
state->addr_family = sa->sa_family;
}
}
/*
* An IPv4 address is in dotted quad decimal form.
*/
else
#endif
{
state->addr = mystrdup(client_addr.buf);
state->rfc_addr = mystrdup(client_addr.buf);
state->addr_family = sa->sa_family;
}
return (0);
}
/*
* It's not Internet.
*/
else {
return (-1);
}
}
static DNS_RR *smtp_addr_one(DNS_RR *addr_list, const char *host,
unsigned pref, DSN_BUF *why)
{
const char *myname = "smtp_addr_one";
DNS_RR *addr = 0;
DNS_RR *rr;
int aierr;
struct addrinfo *res0;
struct addrinfo *res;
INET_PROTO_INFO *proto_info = inet_proto_info();
int found;
if (msg_verbose)
msg_info("%s: host %s", myname, host);
/*
* Interpret a numerical name as an address.
*/
if (hostaddr_to_sockaddr(host, (char *) 0, 0, &res0) == 0
&& strchr((char *) proto_info->sa_family_list, res0->ai_family) != 0) {
if ((addr = dns_sa_to_rr(host, pref, res0->ai_addr)) == 0)
msg_fatal("host %s: conversion error for address family %d: %m",
host, ((struct sockaddr *) (res0->ai_addr))->sa_family);
addr_list = dns_rr_append(addr_list, addr);
freeaddrinfo(res0);
return (addr_list);
}
/*
* Use DNS lookup, but keep the option open to use native name service.
*
* XXX A soft error dominates past and future hard errors. Therefore we
* should not clobber a soft error text and status code.
*/
if (smtp_host_lookup_mask & SMTP_HOST_FLAG_DNS) {
switch (dns_lookup_v(host, smtp_dns_res_opt, &addr, (VSTRING *) 0,
why->reason, DNS_REQ_FLAG_NONE,
proto_info->dns_atype_list)) {
case DNS_OK:
for (rr = addr; rr; rr = rr->next)
rr->pref = pref;
addr_list = dns_rr_append(addr_list, addr);
return (addr_list);
default:
dsb_status(why, "4.4.3");
return (addr_list);
case DNS_FAIL:
dsb_status(why, SMTP_HAS_SOFT_DSN(why) ? "4.4.3" : "5.4.3");
return (addr_list);
case DNS_INVAL:
dsb_status(why, SMTP_HAS_SOFT_DSN(why) ? "4.4.4" : "5.4.4");
return (addr_list);
case DNS_NOTFOUND:
dsb_status(why, SMTP_HAS_SOFT_DSN(why) ? "4.4.4" : "5.4.4");
/* maybe native naming service will succeed */
break;
}
}
/*
* Use the native name service which also looks in /etc/hosts.
*
* XXX A soft error dominates past and future hard errors. Therefore we
* should not clobber a soft error text and status code.
*/
#define RETRY_AI_ERROR(e) \
((e) == EAI_AGAIN || (e) == EAI_MEMORY || (e) == EAI_SYSTEM)
#ifdef EAI_NODATA
#define DSN_NOHOST(e) \
((e) == EAI_AGAIN || (e) == EAI_NODATA || (e) == EAI_NONAME)
#else
#define DSN_NOHOST(e) \
((e) == EAI_AGAIN || (e) == EAI_NONAME)
#endif
if (smtp_host_lookup_mask & SMTP_HOST_FLAG_NATIVE) {
if ((aierr = hostname_to_sockaddr(host, (char *) 0, 0, &res0)) != 0) {
dsb_simple(why, (SMTP_HAS_SOFT_DSN(why) || RETRY_AI_ERROR(aierr)) ?
(DSN_NOHOST(aierr) ? "4.4.4" : "4.3.0") :
(DSN_NOHOST(aierr) ? "5.4.4" : "5.3.0"),
"unable to look up host %s: %s",
host, MAI_STRERROR(aierr));
} else {
for (found = 0, res = res0; res != 0; res = res->ai_next) {
if (strchr((char *) proto_info->sa_family_list, res->ai_family) == 0) {
msg_info("skipping address family %d for host %s",
res->ai_family, host);
continue;
}
found++;
if ((addr = dns_sa_to_rr(host, pref, res->ai_addr)) == 0)
msg_fatal("host %s: conversion error for address family %d: %m",
host, ((struct sockaddr *) (res0->ai_addr))->sa_family);
addr_list = dns_rr_append(addr_list, addr);
}
freeaddrinfo(res0);
if (found == 0) {
dsb_simple(why, SMTP_HAS_SOFT_DSN(why) ? "4.4.4" : "5.4.4",
"%s: host not found", host);
}
return (addr_list);
}
}
/*
* No further alternatives for host lookup.
*/
return (addr_list);
}
void qmqpd_peer_init(QMQPD_STATE *state)
{
const char *myname = "qmqpd_peer_init";
struct sockaddr_storage ss;
struct sockaddr *sa;
SOCKADDR_SIZE sa_length;
INET_PROTO_INFO *proto_info = inet_proto_info();
sa = (struct sockaddr *) & ss;
sa_length = sizeof(ss);
/*
* Look up the peer address information.
*/
if (getpeername(vstream_fileno(state->client), sa, &sa_length) >= 0) {
errno = 0;
}
/*
* If peer went away, give up.
*/
if (errno != 0 && errno != ENOTSOCK) {
state->name = mystrdup(CLIENT_NAME_UNKNOWN);
state->addr = mystrdup(CLIENT_ADDR_UNKNOWN);
state->rfc_addr = mystrdup(CLIENT_ADDR_UNKNOWN);
state->addr_family = AF_UNSPEC;
state->port = mystrdup(CLIENT_PORT_UNKNOWN);
}
/*
* Convert the client address to printable address and hostname.
*
* XXX If we're given an IPv6 (or IPv4) connection from, e.g., inetd, while
* Postfix IPv6 (or IPv4) support is turned off, don't (skip to the final
* else clause, pretend the origin is localhost[127.0.0.1], and become an
* open relay).
*/
else if (errno == 0
&& (sa->sa_family == AF_INET
#ifdef AF_INET6
|| sa->sa_family == AF_INET6
#endif
)) {
MAI_HOSTNAME_STR client_name;
MAI_HOSTADDR_STR client_addr;
MAI_SERVPORT_STR client_port;
int aierr;
char *colonp;
/*
* Sanity check: we can't use sockets that we're not configured for.
*/
if (strchr((char *) proto_info->sa_family_list, sa->sa_family) == 0)
msg_fatal("cannot handle socket type %s with \"%s = %s\"",
#ifdef AF_INET6
sa->sa_family == AF_INET6 ? "AF_INET6" :
#endif
sa->sa_family == AF_INET ? "AF_INET" :
"other", VAR_INET_PROTOCOLS, var_inet_protocols);
/*
* Sorry, but there are some things that we just cannot do while
* connected to the network.
*/
if (geteuid() != var_owner_uid || getuid() != var_owner_uid) {
msg_error("incorrect QMQP server privileges: uid=%lu euid=%lu",
(unsigned long) getuid(), (unsigned long) geteuid());
msg_fatal("the Postfix QMQP server must run with $%s privileges",
VAR_MAIL_OWNER);
}
/*
* Convert the client address to printable form.
*/
if ((aierr = sockaddr_to_hostaddr(sa, sa_length, &client_addr,
&client_port, 0)) != 0)
msg_fatal("%s: cannot convert client address/port to string: %s",
myname, MAI_STRERROR(aierr));
state->port = mystrdup(client_port.buf);
/*
* XXX Require that the infrastructure strips off the IPv6 datalink
* suffix to avoid false alarms with strict address syntax checks.
*/
#ifdef HAS_IPV6
if (strchr(client_addr.buf, '%') != 0)
msg_panic("%s: address %s has datalink suffix",
myname, client_addr.buf);
#endif
/*
* We convert IPv4-in-IPv6 address to 'true' IPv4 address early on,
* but only if IPv4 support is enabled (why would anyone want to turn
* it off)? With IPv4 support enabled we have no need for the IPv6
* form in logging, hostname verification and access checks.
*/
#ifdef HAS_IPV6
if (sa->sa_family == AF_INET6) {
if (strchr((char *) proto_info->sa_family_list, AF_INET) != 0
&& IN6_IS_ADDR_V4MAPPED(&SOCK_ADDR_IN6_ADDR(sa))
&& (colonp = strrchr(client_addr.buf, ':')) != 0) {
struct addrinfo *res0;
if (msg_verbose > 1)
msg_info("%s: rewriting V4-mapped address \"%s\" to \"%s\"",
myname, client_addr.buf, colonp + 1);
state->addr = mystrdup(colonp + 1);
state->rfc_addr = mystrdup(colonp + 1);
state->addr_family = AF_INET;
aierr = hostaddr_to_sockaddr(state->addr, (char *) 0, 0, &res0);
if (aierr)
msg_fatal("%s: cannot convert %s from string to binary: %s",
myname, state->addr, MAI_STRERROR(aierr));
sa_length = res0->ai_addrlen;
if (sa_length > sizeof(ss))
sa_length = sizeof(ss);
memcpy((char *) sa, res0->ai_addr, sa_length);
freeaddrinfo(res0);
}
/*
* Following RFC 2821 section 4.1.3, an IPv6 address literal gets
* a prefix of 'IPv6:'. We do this consistently for all IPv6
* addresses that that appear in headers or envelopes. The fact
* that valid_mailhost_addr() enforces the form helps of course.
* We use the form without IPV6: prefix when doing access
* control, or when accessing the connection cache.
*/
else {
state->addr = mystrdup(client_addr.buf);
state->rfc_addr =
concatenate(IPV6_COL, client_addr.buf, (char *) 0);
state->addr_family = sa->sa_family;
}
}
/*
* An IPv4 address is in dotted quad decimal form.
*/
else
#endif
{
state->addr = mystrdup(client_addr.buf);
state->rfc_addr = mystrdup(client_addr.buf);
state->addr_family = sa->sa_family;
}
/*
* Look up and sanity check the client hostname.
*
* It is unsafe to allow numeric hostnames, especially because there
* exists pressure to turn off the name->addr double check. In that
* case an attacker could trivally bypass access restrictions.
*
* sockaddr_to_hostname() already rejects malformed or numeric names.
*/
#define REJECT_PEER_NAME(state) { \
myfree(state->name); \
state->name = mystrdup(CLIENT_NAME_UNKNOWN); \
}
if ((aierr = sockaddr_to_hostname(sa, sa_length, &client_name,
(MAI_SERVNAME_STR *) 0, 0)) != 0) {
state->name = mystrdup(CLIENT_NAME_UNKNOWN);
} else {
struct addrinfo *res0;
struct addrinfo *res;
state->name = mystrdup(client_name.buf);
/*
* Reject the hostname if it does not list the peer address.
*/
aierr = hostname_to_sockaddr_pf(state->name, state->addr_family,
(char *) 0, 0, &res0);
if (aierr) {
msg_warn("hostname %s does not resolve to address %s: %s",
state->name, state->addr, MAI_STRERROR(aierr));
REJECT_PEER_NAME(state);
} else {
for (res = res0; /* void */ ; res = res->ai_next) {
if (res == 0) {
msg_warn("hostname %s does not resolve to address %s",
state->addr, state->name);
REJECT_PEER_NAME(state);
break;
}
if (strchr((char *) proto_info->sa_family_list, res->ai_family) == 0) {
msg_info("skipping address family %d for host %s",
res->ai_family, state->name);
continue;
}
if (sock_addr_cmp_addr(res->ai_addr, sa) == 0)
break; /* keep peer name */
}
freeaddrinfo(res0);
}
}
}
/*
* If it's not Internet, assume the client is local, and avoid using the
* naming service because that can hang when the machine is disconnected.
*/
else {
state->name = mystrdup("localhost");
state->addr = mystrdup("127.0.0.1"); /* XXX bogus. */
state->rfc_addr = mystrdup("127.0.0.1");/* XXX bogus. */
state->addr_family = AF_UNSPEC;
state->port = mystrdup("0"); /* XXX bogus. */
}
/*
* Do the name[addr]:port formatting for pretty reports.
*/
state->namaddr =
concatenate(state->name, "[", state->addr, "]",
var_qmqpd_client_port_log ? ":" : (char *) 0,
state->port, (char *) 0);
}
