SSL: $ssl_sigalg, $ssl_client_sigalg.

Variables contain the IANA name of the signature scheme[1] used to sign
the TLS handshake.

Variables are only meaningful when using OpenSSL 3.5 and above, with older
versions they are empty.  Moreover, since this data isn't stored in a
serialized session, variables are only available for new sessions.

[1] https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml

Requested by willmafh.

2 files changed, 56 insertions, 0 deletions

diff --git a/src/event/ngx_event_openssl.c b/src/event/ngx_event_openssl.c
index b1ae2955d..5175d7a7e 100644
--- a/src/event/ngx_event_openssl.c
+++ b/src/event/ngx_event_openssl.c
@@ -5541,6 +5541,32 @@ ngx_ssl_get_curves(ngx_connection_t *c, ngx_pool_t *pool, ngx_str_t *s)
 
 
 ngx_int_t
+ngx_ssl_get_sigalg(ngx_connection_t *c, ngx_pool_t *pool, ngx_str_t *s)
+{
+#ifdef SSL_get0_signature_name
+
+    const char  *name;
+
+    if (SSL_get0_signature_name(c->ssl->connection, &name)) {
+        s->len = ngx_strlen(name);
+        s->data = ngx_pnalloc(pool, s->len);
+        if (s->data == NULL) {
+            return NGX_ERROR;
+        }
+
+        ngx_memcpy(s->data, name, s->len);
+
+        return NGX_OK;
+    }
+
+#endif
+
+    s->len = 0;
+    return NGX_OK;
+}
+
+
+ngx_int_t
 ngx_ssl_get_session_id(ngx_connection_t *c, ngx_pool_t *pool, ngx_str_t *s)
 {
     u_char        *buf;
@@ -6285,6 +6311,32 @@ ngx_ssl_parse_time(
 }
 
 
+ngx_int_t
+ngx_ssl_get_client_sigalg(ngx_connection_t *c, ngx_pool_t *pool, ngx_str_t *s)
+{
+#ifdef SSL_get0_peer_signature_name
+
+    const char  *name;
+
+    if (SSL_get0_peer_signature_name(c->ssl->connection, &name)) {
+        s->len = ngx_strlen(name);
+        s->data = ngx_pnalloc(pool, s->len);
+        if (s->data == NULL) {
+            return NGX_ERROR;
+        }
+
+        ngx_memcpy(s->data, name, s->len);
+
+        return NGX_OK;
+    }
+
+#endif
+
+    s->len = 0;
+    return NGX_OK;
+}
+
+
 static void *
 ngx_openssl_create_conf(ngx_cycle_t *cycle)
 {
diff --git a/src/event/ngx_event_openssl.h b/src/event/ngx_event_openssl.h
index 79f96c160..ae0e173de 100644
--- a/src/event/ngx_event_openssl.h
+++ b/src/event/ngx_event_openssl.h
@@ -328,6 +328,8 @@ ngx_int_t ngx_ssl_get_curve(ngx_connection_t *c, ngx_pool_t *pool,
     ngx_str_t *s);
 ngx_int_t ngx_ssl_get_curves(ngx_connection_t *c, ngx_pool_t *pool,
     ngx_str_t *s);
+ngx_int_t ngx_ssl_get_sigalg(ngx_connection_t *c, ngx_pool_t *pool,
+    ngx_str_t *s);
 ngx_int_t ngx_ssl_get_session_id(ngx_connection_t *c, ngx_pool_t *pool,
     ngx_str_t *s);
 ngx_int_t ngx_ssl_get_session_reused(ngx_connection_t *c, ngx_pool_t *pool,
@@ -364,6 +366,8 @@ ngx_int_t ngx_ssl_get_client_v_end(ngx_connection_t *c, ngx_pool_t *pool,
     ngx_str_t *s);
 ngx_int_t ngx_ssl_get_client_v_remain(ngx_connection_t *c, ngx_pool_t *pool,
     ngx_str_t *s);
+ngx_int_t ngx_ssl_get_client_sigalg(ngx_connection_t *c, ngx_pool_t *pool,
+    ngx_str_t *s);
 
 
 ngx_int_t ngx_ssl_handshake(ngx_connection_t *c);