upstream: pass the log-on-stderr flag and log level through to

ssh-sk-helper, making debugging a bit easier. ok markus@

OpenBSD-Commit-ID: 2e7aea6bf5770d3f38b7c7bba891069256c5a49a

3 files changed, 37 insertions, 26 deletions

diff --git a/ssh-sk-client.c b/ssh-sk-client.c
index d3d37f792..9121570dc 100644
--- a/ssh-sk-client.c
+++ b/ssh-sk-client.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-sk-client.c,v 1.4 2020/01/06 02:00:46 djm Exp $ */
+/* $OpenBSD: ssh-sk-client.c,v 1.5 2020/01/10 23:43:26 djm Exp $ */
 /*
  * Copyright (c) 2019 Google LLC
  *
@@ -129,24 +129,32 @@ reap_helper(pid_t pid)
 }
 
 static int
-client_converse(struct sshbuf *req, struct sshbuf **respp, u_int msg)
+client_converse(struct sshbuf *msg, struct sshbuf **respp, u_int type)
 {
-        int oerrno, fd, r2, r = SSH_ERR_INTERNAL_ERROR;
-        u_int rmsg, rerr;
+        int oerrno, fd, r2, ll, r = SSH_ERR_INTERNAL_ERROR;
+        u_int rtype, rerr;
         pid_t pid;
         u_char version;
         void (*osigchld)(int);
-        struct sshbuf *resp = NULL;
+        struct sshbuf *req = NULL, *resp = NULL;
         *respp = NULL;
 
         if ((r = start_helper(&fd, &pid, &osigchld)) != 0)
                 return r;
 
-        if ((resp = sshbuf_new()) == NULL) {
+        if ((req = sshbuf_new()) == NULL || (resp = sshbuf_new()) == NULL) {
                 r = SSH_ERR_ALLOC_FAIL;
                 goto out;
         }
-
+        /* Request preamble: type, log_on_stderr, log_level */
+        ll = log_level_get();
+        if ((r = sshbuf_put_u32(req, type)) != 0 ||
+           (r = sshbuf_put_u8(req, log_is_on_stderr() != 0)) != 0 ||
+           (r = sshbuf_put_u32(req, ll < 0 ? 0 : ll)) != 0 ||
+           (r = sshbuf_putb(req, msg)) != 0) {
+                error("%s: build: %s", __func__, ssh_err(r));
+                goto out;
+        }
         if ((r = ssh_msg_send(fd, SSH_SK_HELPER_VERSION, req)) != 0) {
                 error("%s: send: %s", __func__, ssh_err(r));
                 goto out;
@@ -165,11 +173,11 @@ client_converse(struct sshbuf *req, struct sshbuf **respp, u_int msg)
                 r = SSH_ERR_INVALID_FORMAT;
                 goto out;
         }
-        if ((r = sshbuf_get_u32(resp, &rmsg)) != 0) {
+        if ((r = sshbuf_get_u32(resp, &rtype)) != 0) {
                 error("%s: parse message type: %s", __func__, ssh_err(r));
                 goto out;
         }
-        if (rmsg == SSH_SK_HELPER_ERROR) {
+        if (rtype == SSH_SK_HELPER_ERROR) {
                 if ((r = sshbuf_get_u32(resp, &rerr)) != 0) {
                         error("%s: parse error: %s", __func__, ssh_err(r));
                         goto out;
@@ -181,9 +189,9 @@ client_converse(struct sshbuf *req, struct sshbuf **respp, u_int msg)
                 else
                         r = -(int)rerr;
                 goto out;
-        } else if (rmsg != msg) {
+        } else if (rtype != type) {
                 error("%s: helper returned incorrect message type %u, "
-                    "expecting %u", __func__, rmsg, msg);
+                    "expecting %u", __func__, rtype, type);
                 r = SSH_ERR_INTERNAL_ERROR;
                 goto out;
         }
@@ -202,6 +210,7 @@ client_converse(struct sshbuf *req, struct sshbuf **respp, u_int msg)
                 *respp = resp;
                 resp = NULL;
         }
+        sshbuf_free(req);
         sshbuf_free(resp);
         signal(SIGCHLD, osigchld);
         errno = oerrno;
@@ -235,8 +244,7 @@ sshsk_sign(const char *provider, struct sshkey *key,
                 error("%s: serialize private key: %s", __func__, ssh_err(r));
                 goto out;
         }
-        if ((r = sshbuf_put_u32(req, SSH_SK_HELPER_SIGN)) != 0 ||
-            (r = sshbuf_put_stringb(req, kbuf)) != 0 ||
+        if ((r = sshbuf_put_stringb(req, kbuf)) != 0 ||
             (r = sshbuf_put_cstring(req, provider)) != 0 ||
             (r = sshbuf_put_string(req, data, datalen)) != 0 ||
             (r = sshbuf_put_cstring(req, NULL)) != 0 || /* alg */
@@ -309,8 +317,7 @@ sshsk_enroll(int type, const char *provider_path, const char *device,
                 goto out;
         }
 
-        if ((r = sshbuf_put_u32(req, SSH_SK_HELPER_ENROLL)) != 0 ||
-            (r = sshbuf_put_u32(req, (u_int)type)) != 0 ||
+        if ((r = sshbuf_put_u32(req, (u_int)type)) != 0 ||
             (r = sshbuf_put_cstring(req, provider_path)) != 0 ||
             (r = sshbuf_put_cstring(req, device)) != 0 ||
             (r = sshbuf_put_cstring(req, application)) != 0 ||
@@ -379,8 +386,7 @@ sshsk_load_resident(const char *provider_path, const char *device,
                 goto out;
         }
 
-        if ((r = sshbuf_put_u32(req, SSH_SK_HELPER_LOAD_RESIDENT)) != 0 ||
-            (r = sshbuf_put_cstring(req, provider_path)) != 0 ||
+        if ((r = sshbuf_put_cstring(req, provider_path)) != 0 ||
             (r = sshbuf_put_cstring(req, device)) != 0 ||
             (r = sshbuf_put_cstring(req, pin)) != 0) {
                 error("%s: compose: %s", __func__, ssh_err(r));
diff --git a/ssh-sk-helper.c b/ssh-sk-helper.c
index 85a461d53..a4be9d369 100644
--- a/ssh-sk-helper.c
+++ b/ssh-sk-helper.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-sk-helper.c,v 1.7 2020/01/06 02:00:46 djm Exp $ */
+/* $OpenBSD: ssh-sk-helper.c,v 1.8 2020/01/10 23:43:26 djm Exp $ */
 /*
  * Copyright (c) 2019 Google LLC
  *
@@ -269,9 +269,9 @@ main(int argc, char **argv)
         SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
         LogLevel log_level = SYSLOG_LEVEL_ERROR;
         struct sshbuf *req, *resp;
-        int in, out, ch, r, log_stderr = 0;
-        u_int rtype;
-        uint8_t version;
+        int in, out, ch, r, vflag = 0;
+        u_int rtype, ll = 0;
+        uint8_t version, log_stderr = 0;
 
         sanitise_stdfd();
         log_init(__progname, log_level, log_facility, log_stderr);
@@ -279,7 +279,7 @@ main(int argc, char **argv)
         while ((ch = getopt(argc, argv, "v")) != -1) {
                 switch (ch) {
                 case 'v':
-                        log_stderr = 1;
+                        vflag = 1;
                         if (log_level == SYSLOG_LEVEL_ERROR)
                                 log_level = SYSLOG_LEVEL_DEBUG1;
                         else if (log_level < SYSLOG_LEVEL_DEBUG3)
@@ -290,7 +290,7 @@ main(int argc, char **argv)
                         exit(1);
                 }
         }
-        log_init(__progname, log_level, log_facility, log_stderr);
+        log_init(__progname, log_level, log_facility, vflag);
 
         /*
          * Rearrange our file descriptors a little; we don't trust the
@@ -317,9 +317,14 @@ main(int argc, char **argv)
                     version, SSH_SK_HELPER_VERSION);
         }
 
-        if ((r = sshbuf_get_u32(req, &rtype)) != 0)
+        if ((r = sshbuf_get_u32(req, &rtype)) != 0 ||
+            (r = sshbuf_get_u8(req, &log_stderr)) != 0 ||
+            (r = sshbuf_get_u32(req, &ll)) != 0)
                 fatal("%s: buffer error: %s", __progname, ssh_err(r));
 
+        if (!vflag && log_level_name((LogLevel)ll) != NULL)
+                log_init(__progname, (LogLevel)ll, log_facility, log_stderr);
+
         switch (rtype) {
         case SSH_SK_HELPER_SIGN:
                 resp = process_sign(req);
diff --git a/ssh-sk.h b/ssh-sk.h
index ea9ff6e1a..0f566bbc3 100644
--- a/ssh-sk.h
+++ b/ssh-sk.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-sk.h,v 1.9 2020/01/06 02:00:47 djm Exp $ */
+/* $OpenBSD: ssh-sk.h,v 1.10 2020/01/10 23:43:26 djm Exp $ */
 /*
  * Copyright (c) 2019 Google LLC
  *
@@ -23,7 +23,7 @@ struct sshkey;
 struct sk_option;
 
 /* Version of protocol expected from ssh-sk-helper */
-#define SSH_SK_HELPER_VERSION           4
+#define SSH_SK_HELPER_VERSION           5
 
 /* ssh-sk-helper messages */
 #define SSH_SK_HELPER_ERROR             0       /* Only valid H->C */