Unit test coverage for failed issuer

Test the behavior around an issuer failure -- as long as the cached
pubkey isn't expired, we shouldn't try again for 5 minutes.

test/main.cpp

@@ -1,8 +1,20 @@
 #include "../src/scitokens.h"
 
+#include <pwd.h>
 #include <memory>
 #include <gtest/gtest.h>
 
+#include <openssl/bio.h>
+#include <openssl/err.h>
+#include <openssl/ec.h>
+#include <openssl/pem.h>
+
+#ifndef PICOJSON_USE_INT64
+#define PICOJSON_USE_INT64
+#endif
+#include <picojson/picojson.h>
+#include <sqlite3.h>
+
 namespace {
 
 const char ec_private[] = "-----BEGIN EC PRIVATE KEY-----\n"
@@ -27,6 +39,216 @@ const char ec_public_2[] = "-----BEGIN PUBLIC KEY-----\n"
 "XWCq4E/g2ME/uBOdP8RE0tqle8fxYcaPikgMcppGq2ycTiLGgEYXgsq2JA==\n"
 "-----END PUBLIC KEY-----\n";
 
+/**
+ * Duplicate of get_cache_file from scitokens_cache.cpp; used for direct
+ * SQLite manipulation.
+ */
+std::string
+get_cache_file() {
+
+    const char *xdg_cache_home = getenv("XDG_CACHE_HOME");
+
+    auto bufsize = sysconf(_SC_GETPW_R_SIZE_MAX);
+    bufsize = (bufsize == -1) ? 16384 : bufsize;
+
+    std::unique_ptr<char[]> buf(new char[bufsize]);
+
+    std::string home_dir;
+    struct passwd pwd, *result = NULL;
+    getpwuid_r(geteuid(), &pwd, buf.get(), bufsize, &result);
+    if (result && result->pw_dir) {
+        home_dir = result->pw_dir;
+        home_dir += "/.cache";
+    }
+
+    std::string cache_dir(xdg_cache_home ? xdg_cache_home : home_dir.c_str());
+    if (cache_dir.size() == 0) {
+        return "";
+    }
+
+    int r = mkdir(cache_dir.c_str(), 0700);
+    if ((r < 0) && errno != EEXIST) {
+        return "";
+    }
+
+    std::string keycache_dir = cache_dir + "/scitokens";
+    r = mkdir(keycache_dir.c_str(), 0700);
+    if ((r < 0) && errno != EEXIST) {
+        return "";
+    }
+
+    std::string keycache_file = keycache_dir + "/scitokens_cpp.sqllite";
+    // Assume this isn't needed; we'll trigger it via the "real" cache routines.
+    //initialize_cachedb(keycache_file);
+
+    return keycache_file;
+}
+
+/**
+ * Duplicate of remove_issuer_entry from scitokens_cache.cpp; used for direct cache manipulation
+ */
+void
+remove_issuer_entry(sqlite3 *db, const std::string &issuer, bool new_transaction) {
+
+    if (new_transaction) sqlite3_exec(db, "BEGIN", 0, 0 , 0);
+
+    sqlite3_stmt *stmt;
+    int rc = sqlite3_prepare_v2(db, "DELETE FROM keycache WHERE issuer = ?", -1, &stmt, NULL);
+    if (rc != SQLITE_OK) {
+        sqlite3_close(db);
+        return;
+    }
+
+    if (sqlite3_bind_text(stmt, 1, issuer.c_str(), issuer.size(), SQLITE_STATIC) != SQLITE_OK) {
+        sqlite3_finalize(stmt);
+        sqlite3_close(db);
+        return;
+    }
+
+    rc = sqlite3_step(stmt);
+    if (rc != SQLITE_DONE) {
+        sqlite3_finalize(stmt);
+        sqlite3_close(db);
+        return;
+    }
+
+    sqlite3_finalize(stmt);
+
+    if (new_transaction) sqlite3_exec(db, "COMMIT", 0, 0 , 0);
+}
+
+/**
+ * Duplicate of store_public_keys from scitokens_cache.cpp; used for direct cache manipulation.
+ */
+bool
+store_public_keys(const std::string &issuer, const std::string &keys, int64_t next_update, int64_t expires) {
+
+    picojson::value json_obj;
+    auto err = picojson::parse(json_obj, keys);
+    if (!err.empty() || !json_obj.is<picojson::object>()) {
+        return false;
+    }
+
+    picojson::object top_obj;
+    top_obj["jwks"] = json_obj;
+    top_obj["next_update"] = picojson::value(next_update);
+    top_obj["expires"] = picojson::value(expires);
+    picojson::value db_value(top_obj);
+    std::string db_str = db_value.serialize();
+
+    auto cache_fname = get_cache_file();
+    if (cache_fname.size() == 0) {return false;}
+
+    sqlite3 *db;
+    int rc = sqlite3_open(cache_fname.c_str(), &db);
+    if (rc) {
+        sqlite3_close(db);
+        return false;
+    }   
+
+    sqlite3_exec(db, "BEGIN", 0, 0 , 0);
+
+    remove_issuer_entry(db, issuer, false);
+
+    sqlite3_stmt *stmt;
+    rc = sqlite3_prepare_v2(db, "INSERT INTO keycache VALUES (?, ?)", -1, &stmt, NULL);
+    if (rc != SQLITE_OK) {
+        sqlite3_close(db);
+        return false;
+    }   
+
+    if (sqlite3_bind_text(stmt, 1, issuer.c_str(), issuer.size(), SQLITE_STATIC) != SQLITE_OK) {
+        sqlite3_finalize(stmt); 
+        sqlite3_close(db);
+        return false;
+    }   
+
+    if (sqlite3_bind_text(stmt, 2, db_str.c_str(), db_str.size(), SQLITE_STATIC) != SQLITE_OK) {
+        sqlite3_finalize(stmt); 
+        sqlite3_close(db);
+        return false;
+    }   
+
+    rc = sqlite3_step(stmt);
+    if (rc != SQLITE_DONE) {
+        sqlite3_finalize(stmt);
+        sqlite3_close(db);
+        return false;
+    }   
+
+    sqlite3_exec(db, "COMMIT", 0, 0 , 0);
+
+    sqlite3_finalize(stmt);
+    sqlite3_close(db);
+    return true;
+}
+
+bool
+get_public_keys_from_db(const std::string issuer, int64_t &expires, int64_t &next_update) {
+    auto cache_fname = get_cache_file();
+    if (cache_fname.size() == 0) {return false;}
+
+    sqlite3 *db;
+    int rc = sqlite3_open(cache_fname.c_str(), &db);
+    if (rc) {
+        sqlite3_close(db);
+        return false;
+    }
+
+    sqlite3_stmt *stmt;
+    rc = sqlite3_prepare_v2(db, "SELECT keys from keycache where issuer = ?", -1, &stmt, NULL);
+    if (rc != SQLITE_OK) {
+        sqlite3_close(db);
+        return false;
+    }
+
+    if (sqlite3_bind_text(stmt, 1, issuer.c_str(), issuer.size(), SQLITE_STATIC) != SQLITE_OK) {
+        sqlite3_finalize(stmt);
+        sqlite3_close(db);
+        return false;
+    }
+
+    rc = sqlite3_step(stmt);
+    if (rc == SQLITE_ROW) {
+        const unsigned char * data = sqlite3_column_text(stmt, 0);
+        std::string metadata(reinterpret_cast<const char *>(data));
+        sqlite3_finalize(stmt);
+        picojson::value json_obj;
+        auto err = picojson::parse(json_obj, metadata);
+        if (!err.empty() || !json_obj.is<picojson::object>()) {
+            sqlite3_close(db);
+            return false;
+        }
+        auto top_obj = json_obj.get<picojson::object>();
+        auto iter = top_obj.find("jwks");
+        auto keys_local = iter->second;
+        iter = top_obj.find("expires");
+        if (iter == top_obj.end() || !iter->second.is<int64_t>()) {
+            sqlite3_close(db);
+            return false;
+        }
+        auto expiry = iter->second.get<int64_t>();
+        sqlite3_close(db);
+        iter = top_obj.find("next_update");
+        if (iter == top_obj.end() || !iter->second.is<int64_t>()) {
+            next_update = expiry - 4*3600;
+        } else {
+            next_update = iter->second.get<int64_t>();
+        }
+        expires = expiry;
+        return true;
+    } else if (rc == SQLITE_DONE) {
+        sqlite3_finalize(stmt);
+        sqlite3_close(db);
+        return false;
+    } else {
+        // TODO: log error?
+        sqlite3_finalize(stmt);
+        sqlite3_close(db);
+        return false;
+    }
+}
+
 TEST(SciTokenTest, CreateToken) {
     SciToken token = scitoken_create(nullptr);
     ASSERT_TRUE(token != nullptr);
@@ -63,6 +285,7 @@ class KeycacheTest : public ::testing::Test
 {
     protected:
         std::string demo_scitokens_url = "https://demo.scitokens.org";
+        std::string demo_invalid_url = "https://demo.scitokens.org/invalid";
 
         void SetUp() override {
             char *err_msg;
@@ -77,6 +300,76 @@ class KeycacheTest : public ::testing::Test
 };
 
 
+// Emulate the case of an issuer failure.  Store a public key that
+// is in the need of an update. Make sure, on failure, the next_update
+// is 5 minutes ahead of the present.
+TEST_F(KeycacheTest, FailureTest) {
+    time_t now = time(NULL);
+    const time_t expiry = now + 86400;
+    // Insert a public key that requires an update on next token verification.
+    ASSERT_TRUE(store_public_keys(demo_invalid_url, demo_scitokens2, now - 600, expiry));
+
+    // Create a new token with an invalid signature.
+    OpenSSL_add_all_algorithms();
+    ERR_load_BIO_strings();
+    ERR_load_crypto_strings();
+    auto outbio = BIO_new(BIO_s_mem());
+    ASSERT_TRUE(outbio != nullptr);
+    auto eccgrp = OBJ_txt2nid("secp256k1");
+    auto ecc = EC_KEY_new_by_curve_name(eccgrp);
+    ASSERT_TRUE(1 == EC_KEY_generate_key(ecc));
+
+    auto pkey = EVP_PKEY_new();
+    ASSERT_TRUE(1 == EVP_PKEY_assign_EC_KEY(pkey, ecc));
+    ASSERT_TRUE(1 == PEM_write_bio_PrivateKey(outbio, pkey, NULL, NULL, 0, 0, NULL));
+
+    char *pem_data;
+    long pem_len = BIO_get_mem_data(outbio, &pem_data);
+    std::string pem_str(pem_data, pem_len);
+
+    // Generate a serialized token from the new key.
+    auto key = scitoken_key_create("test_key", "ES256", "", pem_str.c_str(), nullptr);
+    ASSERT_TRUE(key != nullptr);
+
+    auto token = scitoken_create(key);
+    ASSERT_TRUE(token != nullptr);
+
+    auto rv = scitoken_set_claim_string(token, "iss", demo_invalid_url.c_str(), nullptr);
+    ASSERT_TRUE(rv == 0);
+
+    rv = scitoken_set_claim_string(token, "sub", "test_user", nullptr);
+    ASSERT_TRUE(rv == 0);
+
+    scitoken_set_lifetime(token, 86400);
+
+    char *token_encoded;
+    rv = scitoken_serialize(token, &token_encoded, nullptr);
+    ASSERT_TRUE(rv == 0);
+    std::string token_str(token_encoded);
+    free(token_encoded);
+
+    // Try to deserialize the newly generated token.  Should fail as the key doesn't match.
+    auto token_read = scitoken_create(nullptr);
+    ASSERT_TRUE(token_read != nullptr);
+    rv = scitoken_deserialize_v2(token_str.c_str(), token_read, nullptr, nullptr);
+    ASSERT_FALSE(rv == 0);
+
+    // Now, for the real test -- what's the value of expired and next_update?
+    int64_t new_expiry, new_next_update;
+    ASSERT_TRUE(get_public_keys_from_db(demo_invalid_url, new_expiry, new_next_update));
+
+    EXPECT_EQ(new_expiry, expiry);
+    EXPECT_GE(new_next_update, now + 300);
+
+    // Second test: if the expiration is behind us, fetching the key should trigger
+    // a deletion of the key cache.
+    ASSERT_TRUE(store_public_keys(demo_invalid_url, demo_scitokens2, now - 600, now - 600));
+
+    rv = scitoken_deserialize_v2(token_str.c_str(), token_read, nullptr, nullptr);
+
+    ASSERT_FALSE(get_public_keys_from_db(demo_invalid_url, new_expiry, new_next_update));
+}
+
 TEST_F(KeycacheTest, RefreshTest) {
     char *err_msg;
     auto rv = keycache_refresh_jwks(demo_scitokens_url.c_str(), &err_msg);