From ac35c1991288feb0137b2ac2dde85120121fc1b9 Mon Sep 17 00:00:00 2001
From: febo <febo@anza.xyz>
Date: Thu, 16 Jan 2025 12:14:41 +0000
Subject: [PATCH 1/5] Add PdaInfo trait

---
 program/src/processor/mod.rs | 12 ++++++------
 program/src/state/buffer.rs  | 16 +++++++++++++++-
 program/src/state/header.rs  | 17 ++++++++++++++++-
 program/src/state/mod.rs     | 13 +++++++++++++
 4 files changed, 50 insertions(+), 8 deletions(-)

diff --git a/program/src/processor/mod.rs b/program/src/processor/mod.rs
index c45fa9d..7c7b139 100644
--- a/program/src/processor/mod.rs
+++ b/program/src/processor/mod.rs
@@ -1,6 +1,6 @@
 use pinocchio::{account_info::AccountInfo, program_error::ProgramError, pubkey::Pubkey};
 
-use crate::state::{header::Header, AccountDiscriminator};
+use crate::state::{header::Header, AccountDiscriminator, PdaInfo};
 
 pub mod allocate;
 pub mod close;
@@ -113,8 +113,8 @@ fn validate_metadata(metadata: &AccountInfo) -> Result<&Header, ProgramError> {
 /// - [explicit] The `authority` account must match the authority set on the `metadata` account OR
 ///   it must be the program upgrade authority if the `metadata` account is canonical (see `is_program_authority`).
 #[inline(always)]
-fn validate_authority(
-    metadata_header: &Header,
+fn validate_authority<T: PdaInfo>(
+    pda_info: &T,
     authority: &AccountInfo,
     program: &AccountInfo,
     program_data: &AccountInfo,
@@ -124,14 +124,14 @@ fn validate_authority(
         return Err(ProgramError::MissingRequiredSignature);
     }
     // The authority is the set authority.
-    let explicitly_authorized = match metadata_header.authority.as_ref() {
+    let explicitly_authorized = match pda_info.authority() {
         Some(metadata_authority) => metadata_authority == authority.key(),
         None => false,
     };
     // The authority is the program upgrade authority for canonical metadata accounts.
     let authorized = explicitly_authorized
-        || (metadata_header.canonical()
-            && program.key() == &metadata_header.program
+        || (pda_info.is_canonical()
+            && program.key() == pda_info.program()
             && is_program_authority(program, program_data, authority.key())?);
     if !authorized {
         return Err(ProgramError::IncorrectAuthority);
diff --git a/program/src/state/buffer.rs b/program/src/state/buffer.rs
index f5e6f64..d2ec979 100644
--- a/program/src/state/buffer.rs
+++ b/program/src/state/buffer.rs
@@ -1,6 +1,6 @@
 use pinocchio::{program_error::ProgramError, pubkey::Pubkey};
 
-use super::{AccountDiscriminator, ZeroableOption, SEED_LEN};
+use super::{AccountDiscriminator, PdaInfo, ZeroableOption, SEED_LEN};
 
 /// Buffer account header.
 #[repr(C)]
@@ -65,3 +65,17 @@ impl Buffer {
         &mut *(bytes.as_mut_ptr() as *mut Self)
     }
 }
+
+impl PdaInfo for Buffer {
+    fn program(&self) -> &Pubkey {
+        self.program.as_ref().unwrap()
+    }
+
+    fn authority(&self) -> Option<&Pubkey> {
+        self.authority.as_ref()
+    }
+
+    fn is_canonical(&self) -> bool {
+        self.canonical() && self.authority().is_none()
+    }
+}
diff --git a/program/src/state/header.rs b/program/src/state/header.rs
index 1de5dcd..8291588 100644
--- a/program/src/state/header.rs
+++ b/program/src/state/header.rs
@@ -1,7 +1,8 @@
 use pinocchio::{program_error::ProgramError, pubkey::Pubkey};
 
 use super::{
-    AccountDiscriminator, Compression, DataSource, Encoding, Format, ZeroableOption, SEED_LEN,
+    AccountDiscriminator, Compression, DataSource, Encoding, Format, PdaInfo, ZeroableOption,
+    SEED_LEN,
 };
 
 /// Metadata account header.
@@ -106,3 +107,17 @@ impl Header {
         &mut *(bytes.as_mut_ptr() as *mut Self)
     }
 }
+
+impl PdaInfo for Header {
+    fn program(&self) -> &Pubkey {
+        &self.program
+    }
+
+    fn authority(&self) -> Option<&Pubkey> {
+        self.authority.as_ref()
+    }
+
+    fn is_canonical(&self) -> bool {
+        self.canonical()
+    }
+}
diff --git a/program/src/state/mod.rs b/program/src/state/mod.rs
index c8eed95..c0022b0 100644
--- a/program/src/state/mod.rs
+++ b/program/src/state/mod.rs
@@ -32,6 +32,19 @@ impl<'a> Metadata<'a> {
     }
 }
 
+/// Trait representing the common information of a PDA account.
+pub(crate) trait PdaInfo {
+    /// The program that this PDA is associated with.
+    fn program(&self) -> &Pubkey;
+
+    /// The (optional) authority of the PDA.
+    fn authority(&self) -> Option<&Pubkey>;
+
+    /// Indicates whether the PDA represents a canonical PDA for
+    /// the program.
+    fn is_canonical(&self) -> bool;
+}
+
 /// Account discriminators.
 #[repr(u8)]
 #[derive(Clone, Copy, Debug)]

From 497ad1853754b93e2d42fdaacc57ea0c0cba6d4a Mon Sep 17 00:00:00 2001
From: febo <febo@anza.xyz>
Date: Thu, 16 Jan 2025 12:15:15 +0000
Subject: [PATCH 2/5] Refactor authority validation

---
 program/src/processor/close.rs | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/program/src/processor/close.rs b/program/src/processor/close.rs
index d879e39..dd18e64 100644
--- a/program/src/processor/close.rs
+++ b/program/src/processor/close.rs
@@ -1,6 +1,6 @@
 use pinocchio::{account_info::AccountInfo, program_error::ProgramError, ProgramResult};
 
-use crate::state::AccountDiscriminator;
+use crate::state::{buffer::Buffer, AccountDiscriminator};
 
 use super::{validate_authority, validate_metadata};
 
@@ -15,6 +15,10 @@ pub fn close(accounts: &[AccountInfo]) -> ProgramResult {
         return Err(ProgramError::NotEnoughAccountKeys);
     };
 
+    if !authority.is_signer() {
+        return Err(ProgramError::MissingRequiredSignature);
+    }
+
     let account_data = if account.data_is_empty() {
         return Err(ProgramError::UninitializedAccount);
     } else {
@@ -25,19 +29,20 @@ pub fn close(accounts: &[AccountInfo]) -> ProgramResult {
     //  - account: program owned is implicitly checked since we are writing
     //    to the account
 
-    match AccountDiscriminator::try_from(account_data[0])? {
-        AccountDiscriminator::Buffer => {
-            // The authority of a buffer account must be the buffer account
-            // itself.
-            if !(account.key() == authority.key() && authority.is_signer()) {
-                return Err(ProgramError::MissingRequiredSignature);
+    // We only need to validate the authority if it is not a keypair buffer,
+    // since we already validated that the authority is a signer.
+    if account.key() != authority.key() {
+        match AccountDiscriminator::try_from(account_data[0])? {
+            AccountDiscriminator::Buffer => {
+                let buffer = unsafe { Buffer::load_unchecked(account_data) };
+                validate_authority(buffer, authority, program, program_data)?
             }
+            AccountDiscriminator::Metadata => {
+                let header = validate_metadata(account)?;
+                validate_authority(header, authority, program, program_data)?
+            }
+            _ => return Err(ProgramError::InvalidAccountData),
         }
-        AccountDiscriminator::Metadata => {
-            let header = validate_metadata(account)?;
-            validate_authority(header, authority, program, program_data)?
-        }
-        _ => return Err(ProgramError::InvalidAccountData),
     }
 
     // Move the lamports to the destination account.

From 05b22d85f19213853d7aa6b980fb7c5ad83f872a Mon Sep 17 00:00:00 2001
From: febo <febo@anza.xyz>
Date: Thu, 16 Jan 2025 12:23:12 +0000
Subject: [PATCH 3/5] Remove unnecessary condition

---
 program/src/state/buffer.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/program/src/state/buffer.rs b/program/src/state/buffer.rs
index d2ec979..1978603 100644
--- a/program/src/state/buffer.rs
+++ b/program/src/state/buffer.rs
@@ -76,6 +76,6 @@ impl PdaInfo for Buffer {
     }
 
     fn is_canonical(&self) -> bool {
-        self.canonical() && self.authority().is_none()
+        self.canonical()
     }
 }

From 308c17b5ec7d1ffc9cbb52c59cf7f262192cf668 Mon Sep 17 00:00:00 2001
From: febo <febo@anza.xyz>
Date: Thu, 16 Jan 2025 12:27:11 +0000
Subject: [PATCH 4/5] Fix PdaInfo trait

---
 program/src/processor/mod.rs | 2 +-
 program/src/state/buffer.rs  | 4 ++--
 program/src/state/header.rs  | 4 ++--
 program/src/state/mod.rs     | 2 +-
 4 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/program/src/processor/mod.rs b/program/src/processor/mod.rs
index 7c7b139..e994b00 100644
--- a/program/src/processor/mod.rs
+++ b/program/src/processor/mod.rs
@@ -131,7 +131,7 @@ fn validate_authority<T: PdaInfo>(
     // The authority is the program upgrade authority for canonical metadata accounts.
     let authorized = explicitly_authorized
         || (pda_info.is_canonical()
-            && program.key() == pda_info.program()
+            && pda_info.program() == Some(program.key())
             && is_program_authority(program, program_data, authority.key())?);
     if !authorized {
         return Err(ProgramError::IncorrectAuthority);
diff --git a/program/src/state/buffer.rs b/program/src/state/buffer.rs
index 1978603..3406a5a 100644
--- a/program/src/state/buffer.rs
+++ b/program/src/state/buffer.rs
@@ -67,8 +67,8 @@ impl Buffer {
 }
 
 impl PdaInfo for Buffer {
-    fn program(&self) -> &Pubkey {
-        self.program.as_ref().unwrap()
+    fn program(&self) -> Option<&Pubkey> {
+        self.program.as_ref()
     }
 
     fn authority(&self) -> Option<&Pubkey> {
diff --git a/program/src/state/header.rs b/program/src/state/header.rs
index 8291588..40197a0 100644
--- a/program/src/state/header.rs
+++ b/program/src/state/header.rs
@@ -109,8 +109,8 @@ impl Header {
 }
 
 impl PdaInfo for Header {
-    fn program(&self) -> &Pubkey {
-        &self.program
+    fn program(&self) -> Option<&Pubkey> {
+        Some(&self.program)
     }
 
     fn authority(&self) -> Option<&Pubkey> {
diff --git a/program/src/state/mod.rs b/program/src/state/mod.rs
index c0022b0..61aced4 100644
--- a/program/src/state/mod.rs
+++ b/program/src/state/mod.rs
@@ -35,7 +35,7 @@ impl<'a> Metadata<'a> {
 /// Trait representing the common information of a PDA account.
 pub(crate) trait PdaInfo {
     /// The program that this PDA is associated with.
-    fn program(&self) -> &Pubkey;
+    fn program(&self) -> Option<&Pubkey>;
 
     /// The (optional) authority of the PDA.
     fn authority(&self) -> Option<&Pubkey>;

From 55e29ac0b141b2a26c444ea3c41e7ec43a2b8e99 Mon Sep 17 00:00:00 2001
From: febo <febo@anza.xyz>
Date: Sat, 18 Jan 2025 02:59:12 +0000
Subject: [PATCH 5/5] Rename trait

---
 Cargo.lock                   |  4 ++--
 program/src/processor/mod.rs | 20 +++++++++++---------
 program/src/state/buffer.rs  | 14 +++++---------
 program/src/state/header.rs  | 14 +++++---------
 program/src/state/mod.rs     | 15 ++++++---------
 5 files changed, 29 insertions(+), 38 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index afab388..7703f29 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1731,9 +1731,9 @@ checksum = "8b870d8c151b6f2fb93e84a13146138f05d02ed11c7e7c54f8826aaaf7c9f184"
 
 [[package]]
 name = "pinocchio"
-version = "0.7.0"
+version = "0.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2999d06e0c7b659daa8d41d56d906c26531e551d22e49c044339024d3e195ebc"
+checksum = "43a8a77bf74e1c4050a2bad53648acfcfbf22b1806473f9c9334a58ef3b38ec4"
 
 [[package]]
 name = "pinocchio-pubkey"
diff --git a/program/src/processor/mod.rs b/program/src/processor/mod.rs
index e994b00..27acb5a 100644
--- a/program/src/processor/mod.rs
+++ b/program/src/processor/mod.rs
@@ -1,6 +1,6 @@
 use pinocchio::{account_info::AccountInfo, program_error::ProgramError, pubkey::Pubkey};
 
-use crate::state::{header::Header, AccountDiscriminator, PdaInfo};
+use crate::state::{header::Header, Account, AccountDiscriminator};
 
 pub mod allocate;
 pub mod close;
@@ -113,8 +113,8 @@ fn validate_metadata(metadata: &AccountInfo) -> Result<&Header, ProgramError> {
 /// - [explicit] The `authority` account must match the authority set on the `metadata` account OR
 ///   it must be the program upgrade authority if the `metadata` account is canonical (see `is_program_authority`).
 #[inline(always)]
-fn validate_authority<T: PdaInfo>(
-    pda_info: &T,
+fn validate_authority<T: Account>(
+    account: &T,
     authority: &AccountInfo,
     program: &AccountInfo,
     program_data: &AccountInfo,
@@ -123,19 +123,21 @@ fn validate_authority<T: PdaInfo>(
     if !authority.is_signer() {
         return Err(ProgramError::MissingRequiredSignature);
     }
+
     // The authority is the set authority.
-    let explicitly_authorized = match pda_info.authority() {
+    let explicitly_authorized = match account.get_authority() {
         Some(metadata_authority) => metadata_authority == authority.key(),
         None => false,
     };
+
     // The authority is the program upgrade authority for canonical metadata accounts.
     let authorized = explicitly_authorized
-        || (pda_info.is_canonical()
-            && pda_info.program() == Some(program.key())
+        || (account.is_canonical(program.key())
             && is_program_authority(program, program_data, authority.key())?);
+
     if !authorized {
-        return Err(ProgramError::IncorrectAuthority);
+        Err(ProgramError::IncorrectAuthority)
+    } else {
+        Ok(())
     }
-
-    Ok(())
 }
diff --git a/program/src/state/buffer.rs b/program/src/state/buffer.rs
index 3406a5a..264a1c5 100644
--- a/program/src/state/buffer.rs
+++ b/program/src/state/buffer.rs
@@ -1,6 +1,6 @@
 use pinocchio::{program_error::ProgramError, pubkey::Pubkey};
 
-use super::{AccountDiscriminator, PdaInfo, ZeroableOption, SEED_LEN};
+use super::{Account, AccountDiscriminator, ZeroableOption, SEED_LEN};
 
 /// Buffer account header.
 #[repr(C)]
@@ -66,16 +66,12 @@ impl Buffer {
     }
 }
 
-impl PdaInfo for Buffer {
-    fn program(&self) -> Option<&Pubkey> {
-        self.program.as_ref()
-    }
-
-    fn authority(&self) -> Option<&Pubkey> {
+impl Account for Buffer {
+    fn get_authority(&self) -> Option<&Pubkey> {
         self.authority.as_ref()
     }
 
-    fn is_canonical(&self) -> bool {
-        self.canonical()
+    fn is_canonical(&self, program: &Pubkey) -> bool {
+        self.canonical() && self.program.as_ref() == Some(program)
     }
 }
diff --git a/program/src/state/header.rs b/program/src/state/header.rs
index 40197a0..3ef6406 100644
--- a/program/src/state/header.rs
+++ b/program/src/state/header.rs
@@ -1,7 +1,7 @@
 use pinocchio::{program_error::ProgramError, pubkey::Pubkey};
 
 use super::{
-    AccountDiscriminator, Compression, DataSource, Encoding, Format, PdaInfo, ZeroableOption,
+    Account, AccountDiscriminator, Compression, DataSource, Encoding, Format, ZeroableOption,
     SEED_LEN,
 };
 
@@ -108,16 +108,12 @@ impl Header {
     }
 }
 
-impl PdaInfo for Header {
-    fn program(&self) -> Option<&Pubkey> {
-        Some(&self.program)
-    }
-
-    fn authority(&self) -> Option<&Pubkey> {
+impl Account for Header {
+    fn get_authority(&self) -> Option<&Pubkey> {
         self.authority.as_ref()
     }
 
-    fn is_canonical(&self) -> bool {
-        self.canonical()
+    fn is_canonical(&self, program: &Pubkey) -> bool {
+        self.canonical() && self.program == *program
     }
 }
diff --git a/program/src/state/mod.rs b/program/src/state/mod.rs
index 61aced4..2018e83 100644
--- a/program/src/state/mod.rs
+++ b/program/src/state/mod.rs
@@ -32,17 +32,14 @@ impl<'a> Metadata<'a> {
     }
 }
 
-/// Trait representing the common information of a PDA account.
-pub(crate) trait PdaInfo {
-    /// The program that this PDA is associated with.
-    fn program(&self) -> Option<&Pubkey>;
-
-    /// The (optional) authority of the PDA.
-    fn authority(&self) -> Option<&Pubkey>;
+/// Utility trait for an account.
+pub(crate) trait Account {
+    /// Returns the account authority, if there is one.
+    fn get_authority(&self) -> Option<&Pubkey>;
 
     /// Indicates whether the PDA represents a canonical PDA for
-    /// the program.
-    fn is_canonical(&self) -> bool;
+    /// the given program.
+    fn is_canonical(&self, program: &Pubkey) -> bool;
 }
 
 /// Account discriminators.