From e5b3f9c904664a8de5923d8319c28ea922721afe Mon Sep 17 00:00:00 2001
From: Ondrej Kos <okos@redhat.com>
Date: Thu, 8 Nov 2012 14:34:36 +0100
Subject: [PATCH] Display more information on DB version crash

https://fedorahosted.org/sssd/ticket/1589

Added check for determining, whether database version is higher or
lower than expected. To distinguish it from other errors it uses
following retun values (further used for appropriate error message):
EMEDIUMTYPE for lower version than expected
EUCLEAN for higher version than expected

When SSSD or one of it's tools fails on DB version mismatch, new error
message is showed suggesting how to proceed.
---
 src/db/sysdb.c                          | 36 +++++++++++++++++++++++++++++++--
 src/db/sysdb.h                          | 30 +++++++++++++++++++++++++++
 src/monitor/monitor.c                   |  1 +
 src/responder/common/responder_common.c |  1 +
 src/tools/sss_cache.c                   |  2 ++
 src/tools/sss_seed.c                    |  1 +
 src/tools/tools_util.c                  |  1 +
 7 files changed, 70 insertions(+), 2 deletions(-)

diff --git a/src/db/sysdb.c b/src/db/sysdb.c
index 9685163b3f00cc2a45617072efa353589de111ce..dda288f767022fe97b64e36226c5a505eab5abbe 100644
--- a/src/db/sysdb.c
+++ b/src/db/sysdb.c
@@ -947,6 +947,38 @@ errno_t sysdb_add_to_domain(struct sss_domain_info *domain,
     return EOK;
 }
 
+/* Compare versions of sysdb, returns ERRNO accordingly */
+static errno_t
+sysdb_version_check(const char *expected,
+                    const char *received)
+{
+    int ret;
+    unsigned int exp_major, exp_minor, recv_major, recv_minor;
+
+    ret = sscanf(expected, "%u.%u", &exp_major, &exp_minor);
+    if (ret != 2) {
+        return EINVAL;
+    }
+    ret = sscanf(received, "%u.%u", &recv_major, &recv_minor);
+    if (ret != 2) {
+        return EINVAL;
+    }
+
+    if (recv_major > exp_major) {
+        return EUCLEAN;
+    } else if (recv_major < exp_major) {
+        return EMEDIUMTYPE;
+    }
+
+    if (recv_minor > exp_minor) {
+        return EUCLEAN;
+    } else if (recv_minor < exp_minor) {
+        return EMEDIUMTYPE;
+    }
+
+    return EOK;
+}
+
 int sysdb_domain_init_internal(TALLOC_CTX *mem_ctx,
                                struct sss_domain_info *domain,
                                const char *db_path,
@@ -1037,7 +1069,7 @@ int sysdb_domain_init_internal(TALLOC_CTX *mem_ctx,
             if (!allow_upgrade) {
                 DEBUG(0, ("Wrong DB version (got %s expected %s)\n",
                           version, SYSDB_VERSION));
-                ret = EINVAL;
+                ret = sysdb_version_check(SYSDB_VERSION, version);
                 goto done;
             }
 
@@ -1136,7 +1168,7 @@ int sysdb_domain_init_internal(TALLOC_CTX *mem_ctx,
 
         DEBUG(0,("Unknown DB version [%s], expected [%s] for domain %s!\n",
                  version?version:"not found", SYSDB_VERSION, domain->name));
-        ret = EINVAL;
+        ret = sysdb_version_check(SYSDB_VERSION, version);
         goto done;
     }
 
diff --git a/src/db/sysdb.h b/src/db/sysdb.h
index 39e0f9f5245c67f3798055823e98c2db0fbdebba..c60f7e9517428f704b714d837579f132a187b69e 100644
--- a/src/db/sysdb.h
+++ b/src/db/sysdb.h
@@ -214,6 +214,36 @@
 #define SYSDB_MOD_DEL LDB_FLAG_MOD_DELETE
 #define SYSDB_MOD_REP LDB_FLAG_MOD_REPLACE
 
+/* sysdb version check macros */
+#define SYSDB_VERSION_ERROR_HINT \
+    ERROR("Removing cache files in "DB_PATH" should fix the issue, " \
+          "but note that removing cache files will also remove all of your " \
+          "cached credentials.\n")
+
+#define SYSDB_VERSION_LOWER_ERROR(ret) do { \
+    if (ret == EUCLEAN) { \
+        ERROR("Lower version of database is expected!\n"); \
+        SYSDB_VERSION_ERROR_HINT; \
+    } \
+} while(0)
+
+#define SYSDB_VERSION_HIGHER_ERROR(ret) do { \
+    if (ret == EMEDIUMTYPE) { \
+        ERROR("Higher version of database is expected!\n"); \
+        ERROR("In order to upgrade the database, you must run SSSD.\n"); \
+        SYSDB_VERSION_ERROR_HINT; \
+    } \
+} while(0)
+
+/* use this in daemons */
+#define SYSDB_VERSION_ERROR_DAEMON(ret) \
+    SYSDB_VERSION_LOWER_ERROR(ret)
+
+/* use this in tools */
+#define SYSDB_VERSION_ERROR(ret) \
+    SYSDB_VERSION_LOWER_ERROR(ret); \
+    SYSDB_VERSION_HIGHER_ERROR(ret)
+
 struct confdb_ctx;
 struct sysdb_ctx;
 
diff --git a/src/monitor/monitor.c b/src/monitor/monitor.c
index caa157138c19d18b61a77b1f9d4b29ac9e1fb64e..987a78547c745e8283deeb646342734554f1737a 100644
--- a/src/monitor/monitor.c
+++ b/src/monitor/monitor.c
@@ -2185,6 +2185,7 @@ int monitor_process_init(struct mt_ctx *ctx,
     }
     ret = sysdb_init(tmp_ctx, ctx->cdb, NULL, true, &db_list);
     if (ret != EOK) {
+        SYSDB_VERSION_ERROR_DAEMON(ret);
         return ret;
     }
     talloc_zfree(tmp_ctx);
diff --git a/src/responder/common/responder_common.c b/src/responder/common/responder_common.c
index d9f73fe2698cd7eacfb1a589c159e5cb037dab64..50705a3f227d38f7789d4adc5a69d246f4b1be29 100644
--- a/src/responder/common/responder_common.c
+++ b/src/responder/common/responder_common.c
@@ -839,6 +839,7 @@ int sss_process_init(TALLOC_CTX *mem_ctx,
 
     ret = sysdb_init(rctx, cdb, NULL, false, &rctx->db_list);
     if (ret != EOK) {
+        SYSDB_VERSION_ERROR_DAEMON(ret);
         DEBUG(0, ("fatal error initializing resp_ctx\n"));
         return ret;
     }
diff --git a/src/tools/sss_cache.c b/src/tools/sss_cache.c
index 06b0099dc642812752949aa6cb8781ac1349ad90..368b1df9d42f5152df54b5ae94633e74b3154255 100644
--- a/src/tools/sss_cache.c
+++ b/src/tools/sss_cache.c
@@ -339,6 +339,7 @@ errno_t init_domains(struct cache_tool_ctx *ctx, const char *domain)
         ret = sysdb_init_domain_and_sysdb(ctx, ctx->confdb, domain, DB_PATH,
                                           &ctx->domains, &db_ctx);
         if (ret != EOK) {
+            SYSDB_VERSION_ERROR(ret);
             DEBUG(1, ("Could not initialize connection to the sysdb\n"));
             goto fail;
         }
@@ -350,6 +351,7 @@ errno_t init_domains(struct cache_tool_ctx *ctx, const char *domain)
         }
     } else {
         ret = sysdb_init(ctx, ctx->confdb, NULL, false, &ctx->sysdb_list);
+        SYSDB_VERSION_ERROR(ret);
         if (ret != EOK) {
             DEBUG(1, ("Could not initialize connection to the sysdb\n"));
             goto fail;
diff --git a/src/tools/sss_seed.c b/src/tools/sss_seed.c
index cd1b263863e44411e7aac8772c3922178ad9dca4..af296c73a868414be1fbfad72673c051f921b625 100644
--- a/src/tools/sss_seed.c
+++ b/src/tools/sss_seed.c
@@ -631,6 +631,7 @@ static int seed_init_db(TALLOC_CTX *mem_ctx,
     ret = sysdb_init_domain_and_sysdb(tmp_ctx, confdb, domain_name,
                                       DB_PATH, &domain, &sysdb);
     if (ret != EOK) {
+        SYSDB_VERSION_ERROR(ret);
         DEBUG(SSSDBG_CRIT_FAILURE,
               ("Could not initialize connection to domain '%s' in sysdb.%s\n",
                domain_name, ret == ENOENT ? " Domain not found." : ""));
diff --git a/src/tools/tools_util.c b/src/tools/tools_util.c
index 99b79f171d82cde5f1c58988949422981e4d5ee3..73e94136c6d274fde60e0fda8d1fdd8c7ef2747e 100644
--- a/src/tools/tools_util.c
+++ b/src/tools/tools_util.c
@@ -57,6 +57,7 @@ static int setup_db(struct tools_ctx *ctx)
     ret = sysdb_init_domain_and_sysdb(ctx, ctx->confdb, "local", DB_PATH,
                                       &ctx->local, &ctx->sysdb);
     if (ret != EOK) {
+        SYSDB_VERSION_ERROR(ret);
         DEBUG(1, ("Could not initialize connection to the sysdb\n"));
         return ret;
     }
-- 
1.7.11.7

