From d22974b7912fab889a1e3ac73373e429e8b0ed7c Mon Sep 17 00:00:00 2001
From: Benjamin Barenblat <bbaren@mit.edu>
Date: Thu, 6 Aug 2015 10:15:53 -0400
Subject: Make OpenSSL usage thread-safe (closes #206)
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Enable OpenSSL’s multithreading support by defining locking and
thread-ID callbacks.  Remove a lock obviated by this change.
---
 src/c/openssl.c | 40 ++++++++++++++++++++++++++++++++++++++++
 src/c/urweb.c   |  5 -----
 2 files changed, 40 insertions(+), 5 deletions(-)

(limited to 'src/c')

diff --git a/src/c/openssl.c b/src/c/openssl.c
index 1d820a34..6d018707 100644
--- a/src/c/openssl.c
+++ b/src/c/openssl.c
@@ -1,5 +1,6 @@
 #include "config.h"
 
+#include <assert.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <sys/types.h>
@@ -7,12 +8,17 @@
 #include <fcntl.h>
 #include <stdio.h>
 #include <string.h>
+#include <pthread.h>
 
+#include <openssl/crypto.h>
 #include <openssl/sha.h>
 #include <openssl/rand.h>
 
 #define PASSSIZE 4
 
+// OpenSSL locks array.  See threads(3SSL).
+static pthread_mutex_t *openssl_locks;
+
 int uw_hash_blocksize = 32;
 
 static int password[PASSSIZE];
@@ -27,7 +33,41 @@ static void random_password() {
   }
 }
 
+// OpenSSL callbacks
+static void thread_id(CRYPTO_THREADID *const result) {
+  CRYPTO_THREADID_set_numeric(result, pthread_self());
+}
+static void lock_or_unlock(const int mode, const int type, const char *file,
+                           const int line) {
+  pthread_mutex_t *const lock = &openssl_locks[type];
+  if (mode & CRYPTO_LOCK) {
+    if (pthread_mutex_lock(lock)) {
+      fprintf(stderr, "Can't take lock at %s:%d\n", file, line);
+      exit(1);
+    }
+  } else {
+    if (pthread_mutex_unlock(lock)) {
+      fprintf(stderr, "Can't release lock at %s:%d\n", file, line);
+      exit(1);
+    }
+  }
+}
+
 void uw_init_crypto() {
+  int i;
+  // Set up OpenSSL.
+  assert(openssl_locks == NULL);
+  openssl_locks = malloc(CRYPTO_num_locks() * sizeof(pthread_mutex_t));
+  if (!openssl_locks) {
+    perror("malloc");
+    exit(1);
+  }
+  for (i = 0; i < CRYPTO_num_locks(); ++i) {
+    pthread_mutex_init(&(openssl_locks[i]), NULL);
+  }
+  CRYPTO_THREADID_set_callback(thread_id);
+  CRYPTO_set_locking_callback(lock_or_unlock);
+  // Prepare signatures.
   if (uw_sig_file) {
     int fd;
 
diff --git a/src/c/urweb.c b/src/c/urweb.c
index 1e49dae0..6d3836f1 100644
--- a/src/c/urweb.c
+++ b/src/c/urweb.c
@@ -167,13 +167,8 @@ void *uw_init_client_data();
 void uw_free_client_data(void *);
 void uw_copy_client_data(void *dst, void *src);
 
-static pthread_mutex_t rand_mutex = PTHREAD_MUTEX_INITIALIZER;
-
 static uw_Basis_int my_rand() {
-  pthread_mutex_lock(&rand_mutex);
   int ret, r = RAND_bytes((unsigned char *)&ret, sizeof ret);
-  pthread_mutex_unlock(&rand_mutex);
-
   if (r)
     return abs(ret);
   else
-- 
cgit v1.2.3


From 98230036ecde51e20e749f8817d11215d4b74265 Mon Sep 17 00:00:00 2001
From: Adam Chlipala <adam@chlipala.net>
Date: Thu, 20 Aug 2015 15:11:40 -0400
Subject: Beautify '-h' output for web servers

---
 src/c/http.c     | 2 +-
 src/settings.sml | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

(limited to 'src/c')

diff --git a/src/c/http.c b/src/c/http.c
index e6c7b1af..9059746f 100644
--- a/src/c/http.c
+++ b/src/c/http.c
@@ -314,7 +314,7 @@ static void *worker(void *data) {
 }
 
 static void help(char *cmd) {
-  printf("Usage: %s [-p <port>] [-a <IP address>] [-t <thread count>] [-k] [-q] [-T SEC]\nThe '-k' option turns on HTTP keepalive.\nThe '-q' option turns off some chatter on stdout.\nThe -T option sets socket recv timeout (0 disables timeout, default is 5 sec)", cmd);
+  printf("Usage: %s [-p <port>] [-a <IP address>] [-t <thread count>] [-k] [-q] [-T SEC]\nThe '-k' option turns on HTTP keepalive.\nThe '-q' option turns off some chatter on stdout.\nThe '-T' option sets socket recv timeout (0 disables timeout, default is 5 sec).\n", cmd);
 }
 
 static void sigint(int signum) {
diff --git a/src/settings.sml b/src/settings.sml
index cd2de8a9..10a4af48 100644
--- a/src/settings.sml
+++ b/src/settings.sml
@@ -883,7 +883,7 @@ fun addFile {Uri, LoadFromFilename} =
             if path' = path then
                 ()
             else
-                ErrorMsg.error ("Two different files requested for URI " ^ Uri)
+                ErrorMsg.error ("Two different files requested for URI " ^ Uri ^ " ( " ^ path' ^ " vs. " ^ path ^ ")")
           | NONE =>
             let
                 val inf = BinIO.openIn path
-- 
cgit v1.2.3