db: add conditional decoding for MySQL

With the udpate to sqlx, we are no longer able
to transparently convert SQL BLOBS (such as longtext)
to Rust strings when using the mysql driver.

Add some branches to convert these into bytes first
and then to strings.

Signed-off-by: Tobin Feldman-Fitzthum <[email protected]>

src/db.rs

@@ -7,7 +7,6 @@ use crate::policy;
 use crate::request;
 
 use anyhow::*;
-use log::*;
 use rand::Rng;
 use std::env;
 use std::result::Result::Ok;
@@ -267,12 +266,41 @@ impl KbsDb {
             .fetch_one(&self.dbpool)
             .await?;
 
+        // Conditional Decoding to work around MySQL limitations
+        // Ideally this would be extracted into a separate function.
+        let allowed_digests_string = match self.r#type {
+            DbType::MySQL => {
+                let bytes = policy_row.try_get::<Vec<u8>, _>(0)?;
+                std::string::String::from_utf8(bytes)?
+            }
+            _ => policy_row.try_get::<String, _>(0)?,
+        };
+        let allowed_digests = serde_json::from_str(&allowed_digests_string)?;
+
+        let allowed_policies_string = match self.r#type {
+            DbType::MySQL => {
+                let bytes = policy_row.try_get::<Vec<u8>, _>(1)?;
+                std::string::String::from_utf8(bytes)?
+            }
+            _ => policy_row.try_get::<String, _>(1)?,
+        };
+        let allowed_policies = serde_json::from_str(&allowed_policies_string)?;
+
+        let allowed_build_ids_string = match self.r#type {
+            DbType::MySQL => {
+                let bytes = policy_row.try_get::<Vec<u8>, _>(4)?;
+                std::string::String::from_utf8(bytes)?
+            }
+            _ => policy_row.try_get::<String, _>(4)?,
+        };
+        let allowed_build_ids = serde_json::from_str(&allowed_build_ids_string)?;
+
         Ok(policy::Policy {
-            allowed_digests: serde_json::from_str(&policy_row.try_get::<String, _>(0)?)?,
-            allowed_policies: serde_json::from_str(&policy_row.try_get::<String, _>(1)?)?,
+            allowed_digests,
+            allowed_policies,
             min_fw_api_major: policy_row.try_get::<i32, _>(2)? as u32,
             min_fw_api_minor: policy_row.try_get::<i32, _>(3)? as u32,
-            allowed_build_ids: serde_json::from_str(&policy_row.try_get::<String, _>(4)?)?,
+            allowed_build_ids,
         })
     }
 
@@ -363,32 +391,22 @@ impl KbsDb {
         let query_str = "SELECT kskeys FROM keysets WHERE keysetid = ?";
         let new_query_str = self.replace_binds(query_str);
 
-        // Need to check 2 cases: 1) no keyset keys are returned from the query; 2) keysets are
-        // returned but cannot be deserialized into JSON by serde_json::from_str().
-        let keyset_row = match sqlx::query(&new_query_str)
+        if let Ok(keyset_row) = sqlx::query(&new_query_str)
             .bind(keysetid)
             .fetch_one(&self.dbpool)
             .await
         {
-            Ok(ksr) => ksr,
-            Err(e) => {
-                warn!(
-                    "db::get_keyset_ids did not return keyset ids for id {}, query error {}",
-                    keysetid, e
-                );
-                return Ok(Vec::<String>::new());
-            }
-        };
-
-        match serde_json::from_str(&keyset_row.try_get::<String, _>(0)?) {
-            Ok(rkv) => Ok(rkv),
-            Err(e) => {
-                warn!(
-                    "db::get_keyset_ids did return a row for keyset id {}, but was not able to create JSON using serde_json::from_str() with error {}",
-                    keysetid, e
-                );
-                Ok(Vec::<String>::new())
-            }
+            let keyset_string = match self.r#type {
+                DbType::MySQL => {
+                    let keyset_bytes = keyset_row.try_get::<Vec<u8>, _>(0)?;
+                    std::string::String::from_utf8(keyset_bytes)?
+                }
+                _ => keyset_row.try_get::<String, _>(0)?,
+            };
+
+            Ok(serde_json::from_str(&keyset_string).unwrap_or(Vec::<String>::new()))
+        } else {
+            Ok(Vec::<String>::new())
         }
     }
 
@@ -769,7 +787,7 @@ mod tests {
 
         let polid = db.insert_policy(&testpol).await?;
 
-        let mut tid = "man-moon-dog-face-in-the-banana-patch-ksp".to_string();
+        let tid = "man-moon-dog-face-in-the-banana-patch-ksp".to_string();
 
         let pkcs8_dummy_bytes = [0xa5u8; 512];
 
@@ -784,7 +802,7 @@ mod tests {
 
         // Now test report_keypair without a policy
 
-        tid = "the-quick-brown-cow-jumped-over-the-moon-no-policy".to_string();
+        let tid = "the-quick-brown-cow-jumped-over-the-moon-no-policy".to_string();
 
         db.insert_report_keypair(&tid, &pkcs8_dummy_bytes, None)
             .await?;