From edc5faffd625286e807f9f770db9dd523d24df38 Mon Sep 17 00:00:00 2001
From: Frank Denis <github@pureftpd.org>
Date: Fri, 26 Apr 2013 17:27:55 -0700
Subject: [PATCH] Add more information about thread safety until we provide a
 thread-safe API.

---
 README.markdown                                           | 2 +-
 src/libsodium/include/sodium/crypto_box.h                 | 7 +++++++
 src/libsodium/include/sodium/crypto_sign.h                | 7 +++++++
 src/libsodium/include/sodium/randombytes_salsa20_random.h | 6 ++++++
 src/libsodium/include/sodium/randombytes_sysrandom.h      | 6 ++++++
 5 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/README.markdown b/README.markdown
index 0714325d..46029b2d 100644
--- a/README.markdown
+++ b/README.markdown
@@ -94,7 +94,7 @@ Sodium also provides helper functions to generate random numbers,
 leveraging `/dev/urandom` or `/dev/random` on *nix and the cryptographic
 service provider on Windows. The interface is similar to
 `arc4random(3)`. It is `fork(2)`-safe but not thread-safe. This holds
-true for `crypto_sign_keypair()` as well.
+true for `crypto_sign_keypair()` and `crypto_box_keypair()` as well.
 
     uint32_t randombytes_random(void);
 
diff --git a/src/libsodium/include/sodium/crypto_box.h b/src/libsodium/include/sodium/crypto_box.h
index 11cf4279..ec2c1f86 100644
--- a/src/libsodium/include/sodium/crypto_box.h
+++ b/src/libsodium/include/sodium/crypto_box.h
@@ -1,6 +1,13 @@
 #ifndef crypto_box_H
 #define crypto_box_H
 
+/*
+ * THREAD SAFETY: crypto_box_keypair() is thread-safe,
+ * provided that you called sodium_init() once before using any
+ * other libsodium function.
+ * Other functions are always thread-safe.
+ */
+
 #include <stdlib.h>
 
 #include "crypto_box_curve25519xsalsa20poly1305.h"
diff --git a/src/libsodium/include/sodium/crypto_sign.h b/src/libsodium/include/sodium/crypto_sign.h
index dd7d9e5a..d8de83c6 100644
--- a/src/libsodium/include/sodium/crypto_sign.h
+++ b/src/libsodium/include/sodium/crypto_sign.h
@@ -1,6 +1,13 @@
 #ifndef crypto_sign_H
 #define crypto_sign_H
 
+/*
+ * THREAD SAFETY: crypto_sign_keypair() is thread-safe,
+ * provided that you called sodium_init() once before using any
+ * other libsodium function.
+ * Other functions, including crypto_sign_seed_keypair() are always thread-safe.
+ */
+
 #include <stdlib.h>
 
 #include "crypto_sign_ed25519.h"
diff --git a/src/libsodium/include/sodium/randombytes_salsa20_random.h b/src/libsodium/include/sodium/randombytes_salsa20_random.h
index f6b66b7c..377c1440 100644
--- a/src/libsodium/include/sodium/randombytes_salsa20_random.h
+++ b/src/libsodium/include/sodium/randombytes_salsa20_random.h
@@ -2,6 +2,12 @@
 #ifndef randombytes_salsa20_random_H
 #define randombytes_salsa20_random_H
 
+/*
+ * THREAD SAFETY: randombytes_salsa20_random*() functions are
+ * fork()-safe but not thread-safe.
+ * Always wrap them in a mutex if you need thread safety.
+ */
+
 #include <stdint.h>
 #include <stdlib.h>
 
diff --git a/src/libsodium/include/sodium/randombytes_sysrandom.h b/src/libsodium/include/sodium/randombytes_sysrandom.h
index 49ec967d..0ef09ea8 100644
--- a/src/libsodium/include/sodium/randombytes_sysrandom.h
+++ b/src/libsodium/include/sodium/randombytes_sysrandom.h
@@ -2,6 +2,12 @@
 #ifndef randombytes_sysrandom_H
 #define randombytes_sysrandom_H
 
+/*
+ * THREAD SAFETY: randombytes_sysrandom() functions are thread-safe,
+ * provided that you called sodium_init() once before using any
+ * other libsodium function.
+ */
+
 #include <stdint.h>
 #include <stdlib.h>