Gitweb:
https://git.exim.org/exim.git/commitdiff/e1aca33756f73c22b00a98d40ce2be8ed94464b1
Commit: e1aca33756f73c22b00a98d40ce2be8ed94464b1
Parent: 7fa5764c203f2f4a900898a79ed02d674075313f
Author: Jeremy Harris <jgh146exb@???>
AuthorDate: Thu Jan 5 13:03:37 2023 +0000
Committer: Jeremy Harris <jgh146exb@???>
CommitDate: Thu Jan 5 13:55:33 2023 +0000
OpenSSL: log conns rejected for bad ALPN, with the offered value
Unfortunately, no way to do this under GnuTLS
---
src/src/match.c | 1 +
src/src/tls-gnu.c | 9 ++++++++-
src/src/tls-openssl.c | 13 +++++++++++--
test/log/1190 | 2 ++
test/runtest | 3 +++
5 files changed, 25 insertions(+), 3 deletions(-)
diff --git a/src/src/match.c b/src/src/match.c
index 91a49c0f0..07070362d 100644
--- a/src/src/match.c
+++ b/src/src/match.c
@@ -968,6 +968,7 @@ Arguments:
s string to search for
listptr ptr to ptr to colon separated list of patterns, or NULL
sep a separator value for the list (see string_nextinlist())
+ or zero for auto
anchorptr ptr to tree for named items, or NULL if no named items
cache_bits ptr to cache_bits for ditto, or NULL if not caching
type MCL_DOMAIN when matching a domain list
diff --git a/src/src/tls-gnu.c b/src/src/tls-gnu.c
index 729fb5879..b47fabf1d 100644
--- a/src/src/tls-gnu.c
+++ b/src/src/tls-gnu.c
@@ -1119,21 +1119,28 @@ switch (tls_id)
/* The format of "data" here doesn't seem to be documented, but appears
to be a 2-byte field with a (redundant, given the "size" arg) total length
then a sequence of one-byte size then string (not nul-term) names. The
- latter is as described in OpenSSL documentation. */
+ latter is as described in OpenSSL documentation.
+ Note that we do not get called for a match_fail, making it hard to log
+ a single bad ALPN being offered (the common case). */
+ {
+ gstring * g = NULL;
DEBUG(D_tls) debug_printf("Seen ALPN extension from client (s=%u):", size);
for (const uschar * s = data+2; s-data < size-1; s += *s + 1)
{
server_seen_alpn++;
+ g = string_append_listele_n(g, ':', s+1, *s);
DEBUG(D_tls) debug_printf(" '%.*s'", (int)*s, s+1);
}
DEBUG(D_tls) debug_printf("\n");
if (server_seen_alpn > 1)
{
+ log_write(0, LOG_MAIN, "TLS ALPN (%s) rejected", string_from_gstring(g));
DEBUG(D_tls) debug_printf("TLS: too many ALPNs presented in handshake\n");
return GNUTLS_E_NO_APPLICATION_PROTOCOL;
}
break;
+ }
#endif
}
return 0;
diff --git a/src/src/tls-openssl.c b/src/src/tls-openssl.c
index e063d29bd..513ba0d3a 100644
--- a/src/src/tls-openssl.c
+++ b/src/src/tls-openssl.c
@@ -2324,6 +2324,8 @@ static int
tls_server_alpn_cb(SSL *ssl, const uschar ** out, uschar * outlen,
const uschar * in, unsigned int inlen, void * arg)
{
+gstring * g = NULL;
+
server_seen_alpn = TRUE;
DEBUG(D_tls)
{
@@ -2354,12 +2356,19 @@ if ( inlen > 1 /* at least one name */
}
}
-/* More than one name from clilent, or name did not match our list. */
+/* More than one name from client, or name did not match our list. */
/* This will be fatal to the TLS conn; would be nice to kill TCP also.
Maybe as an option in future; for now leave control to the config (must-tls). */
-DEBUG(D_tls) debug_printf("TLS ALPN rejected\n");
+for (int pos = 0, siz; pos < inlen; pos += siz+1)
+ {
+ siz = in[pos];
+ if (pos + 1 + siz > inlen) siz = inlen - pos - 1;
+ g = string_append_listele_n(g, ':', in + pos + 1, siz);
+ }
+log_write(0, LOG_MAIN, "TLS ALPN (%s) rejected", string_from_gstring(g));
+gstring_release_unused(g);
return SSL_TLSEXT_ERR_ALERT_FATAL;
}
#endif /* EXIM_HAVE_ALPN */
diff --git a/test/log/1190 b/test/log/1190
index 53c56f59a..e01fb2685 100644
--- a/test/log/1190
+++ b/test/log/1190
@@ -23,7 +23,9 @@
1999-03-02 09:44:33 10HmaY-0005vi-00 <= CALLER@??? H=the.local.host.name (myhost.test.ex) [ip4.ip4.ip4.ip4] P=esmtps X=TLS1.x:ke-RSA-AES256-SHAnnn:xxx CV=no S=sss id=E10HmaX-0005vi-00@???
1999-03-02 09:44:33 10HmaY-0005vi-00 => :blackhole: <a@???> R=server
1999-03-02 09:44:33 10HmaY-0005vi-00 Completed
+1999-03-02 09:44:33 TLS ALPN (http) rejected
1999-03-02 09:44:33 TLS error on connection from the.local.host.name (myhost.test.ex) [ip4.ip4.ip4.ip4] (SSL_accept): error: <<detail omitted>>
+1999-03-02 09:44:33 TLS ALPN (smtp:smtp) rejected
1999-03-02 09:44:33 TLS error on connection from the.local.host.name (myhost.test.ex) [ip4.ip4.ip4.ip4] (SSL_accept): error: <<detail omitted>>
1999-03-02 09:44:33 10HmbC-0005vi-00 <= CALLER@??? H=the.local.host.name (myhost.test.ex) [ip4.ip4.ip4.ip4] P=esmtps X=TLS1.x:ke-RSA-AES256-SHAnnn:xxx CV=no S=sss id=E10HmbB-0005vi-00@???
1999-03-02 09:44:33 10HmbC-0005vi-00 => :blackhole: <d@???> R=server
diff --git a/test/runtest b/test/runtest
index 900fc7bbb..86fc79acb 100755
--- a/test/runtest
+++ b/test/runtest
@@ -1562,6 +1562,9 @@ RESET_AFTER_EXTRA_LINE_READ:
s/signer: [^ ]* bits:\K 256/ 253/;
s/public key too short:\K 256 bits/ 253 bits/;
+ # with GnuTLS we cannot log single bad ALPN. So ignore the with-OpenSSL log line.
+ # next if /TLS ALPN (http) rejected$/;
+
# port numbers
s/(?:\[[^\]]*\]:|port )\K$parm_port_d/PORT_D/;
s/(?:\[[^\]]*\]:|port )\K$parm_port_d2/PORT_D2/;
