BUG/MINOR: jwt: don't try to load files with HMAC algorithm

When trying to use a HMAC algorithm (HS256, HS384, HS512) the
sample_conv_jwt_verify_check() function of the converter tries to load a
file even if it is only supposed to contain a secret instead of a path.

When using lua, the check function is called at runtime so it even tries
to load file at each call... This fixes the issue for HMAC algorithm
but this is still a problem with the other algorithms, since we don't
have a way of pre-loading files before the call.

Another solution must be found to prevent disk IO with lua using other
algorithms.

Must be backported as far as 2.6.

(cherry picked from commit 883f1bdbcec7882a2e4a257e93f92be604467319)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>

diff --git a/src/sample.c b/src/sample.c
index 3e5b576..1756c0e 100644 (file)
--- a/src/sample.c
+++ b/src/sample.c
@@ -4262,11 +4262,12 @@ static int sample_conv_json_query(const struct arg *args, struct sample *smp, vo
 static int sample_conv_jwt_verify_check(struct arg *args, struct sample_conv *conv,
                                        const char *file, int line, char **err)
 {
+       enum jwt_alg alg;
        vars_check_arg(&args[0], NULL);
        vars_check_arg(&args[1], NULL);
 
        if (args[0].type == ARGT_STR) {
-               enum jwt_alg alg = jwt_parse_alg(args[0].data.str.area, args[0].data.str.data);
+               alg = jwt_parse_alg(args[0].data.str.area, args[0].data.str.data);
 
                if (alg == JWT_ALG_DEFAULT) {
                        memprintf(err, "unknown JWT algorithm: %s", args[0].data.str.area);
@@ -4275,7 +4276,16 @@ static int sample_conv_jwt_verify_check(struct arg *args, struct sample_conv *co
        }
 
        if (args[1].type == ARGT_STR) {
-               jwt_tree_load_cert(args[1].data.str.area, args[1].data.str.data, err);
+               switch (alg) {
+                       JWS_ALG_HS256:
+                       JWS_ALG_HS384:
+                       JWS_ALG_HS512:
+                       /* don't try to load a file with HMAC algorithms */
+                               break;
+                       default:
+                               jwt_tree_load_cert(args[1].data.str.area, args[1].data.str.data, err);
+                               break;
+               }
        }
 
        return 1;