Add m-esr52 at 52.6.0

1 files changed, 182 insertions, 0 deletions

diff --git a/security/nss/lib/util/secload.c b/security/nss/lib/util/secload.c
new file mode 100644
index 000000000..12efd2f75
--- /dev/null
+++ b/security/nss/lib/util/secload.c
@@ -0,0 +1,182 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "secport.h"
+#include "nspr.h"
+
+#ifdef XP_UNIX
+#include <unistd.h>
+#define BL_MAXSYMLINKS 20
+
+/*
+ * If 'link' is a symbolic link, this function follows the symbolic links
+ * and returns the pathname of the ultimate source of the symbolic links.
+ * If 'link' is not a symbolic link, this function returns NULL.
+ * The caller should call PR_Free to free the string returned by this
+ * function.
+ */
+static char*
+loader_GetOriginalPathname(const char* link)
+{
+    char* resolved = NULL;
+    char* input = NULL;
+    PRUint32 iterations = 0;
+    PRInt32 len = 0, retlen = 0;
+    if (!link) {
+        PR_SetError(PR_INVALID_ARGUMENT_ERROR, 0);
+        return NULL;
+    }
+    len = PR_MAX(1024, strlen(link) + 1);
+    resolved = PR_Malloc(len);
+    input = PR_Malloc(len);
+    if (!resolved || !input) {
+        if (resolved) {
+            PR_Free(resolved);
+        }
+        if (input) {
+            PR_Free(input);
+        }
+        return NULL;
+    }
+    strcpy(input, link);
+    while ((iterations++ < BL_MAXSYMLINKS) &&
+           ((retlen = readlink(input, resolved, len - 1)) > 0)) {
+        char* tmp = input;
+        resolved[retlen] = '\0'; /* NULL termination */
+        input = resolved;
+        resolved = tmp;
+    }
+    PR_Free(resolved);
+    if (iterations == 1 && retlen < 0) {
+        PR_Free(input);
+        input = NULL;
+    }
+    return input;
+}
+#endif /* XP_UNIX */
+
+/*
+ * Load the library with the file name 'name' residing in the same
+ * directory as the reference library, whose pathname is 'referencePath'.
+ */
+static PRLibrary*
+loader_LoadLibInReferenceDir(const char* referencePath, const char* name)
+{
+    PRLibrary* dlh = NULL;
+    char* fullName = NULL;
+    char* c;
+    PRLibSpec libSpec;
+
+    /* Remove the trailing filename from referencePath and add the new one */
+    c = strrchr(referencePath, PR_GetDirectorySeparator());
+    if (c) {
+        size_t referencePathSize = 1 + c - referencePath;
+        fullName = (char*)PORT_Alloc(strlen(name) + referencePathSize + 1);
+        if (fullName) {
+            memcpy(fullName, referencePath, referencePathSize);
+            strcpy(fullName + referencePathSize, name);
+#ifdef DEBUG_LOADER
+            PR_fprintf(PR_STDOUT, "\nAttempting to load fully-qualified %s\n",
+                       fullName);
+#endif
+            libSpec.type = PR_LibSpec_Pathname;
+            libSpec.value.pathname = fullName;
+            dlh = PR_LoadLibraryWithFlags(libSpec, PR_LD_NOW | PR_LD_LOCAL
+#ifdef PR_LD_ALT_SEARCH_PATH
+                                                       /* allow library's dependencies to be found in the same directory
+                                                        * on Windows even if PATH is not set. Requires NSPR 4.8.1 . */
+                                                       | PR_LD_ALT_SEARCH_PATH
+#endif
+                                          );
+            PORT_Free(fullName);
+        }
+    }
+    return dlh;
+}
+
+/*
+ * Load a shared library called "newShLibName" in the same directory as
+ * a shared library that is already loaded, called existingShLibName.
+ * A pointer to a static function in that shared library,
+ * staticShLibFunc, is required.
+ *
+ * existingShLibName:
+ *   The file name of the shared library that shall be used as the
+ *   "reference library". The loader will attempt to load the requested
+ *   library from the same directory as the reference library.
+ *
+ * staticShLibFunc:
+ *   Pointer to a static function in the "reference library".
+ *
+ * newShLibName:
+ *   The simple file name of the new shared library to be loaded.
+ *
+ * We use PR_GetLibraryFilePathname to get the pathname of the loaded
+ * shared lib that contains this function, and then do a
+ * PR_LoadLibraryWithFlags with an absolute pathname for the shared
+ * library to be loaded.
+ *
+ * On Windows, the "alternate search path" strategy is employed, if available.
+ * On Unix, if existingShLibName is a symbolic link, and no link exists for the
+ * new library, the original link will be resolved, and the new library loaded
+ * from the resolved location.
+ *
+ * If the new shared library is not found in the same location as the reference
+ * library, it will then be loaded from the normal system library path.
+ *
+ */
+
+PRLibrary*
+PORT_LoadLibraryFromOrigin(const char* existingShLibName,
+                           PRFuncPtr staticShLibFunc,
+                           const char* newShLibName)
+{
+    PRLibrary* lib = NULL;
+    char* fullPath = NULL;
+    PRLibSpec libSpec;
+
+    /* Get the pathname for existingShLibName, e.g. /usr/lib/libnss3.so
+     * PR_GetLibraryFilePathname works with either the base library name or a
+     * function pointer, depending on the platform.
+     * We require the address of a function in the "reference library",
+     * provided by the caller. To avoid getting the address of the stub/thunk
+     * of an exported function by accident, use the address of a static
+     * function rather than an exported function.
+     */
+    fullPath = PR_GetLibraryFilePathname(existingShLibName,
+                                         staticShLibFunc);
+
+    if (fullPath) {
+        lib = loader_LoadLibInReferenceDir(fullPath, newShLibName);
+#ifdef XP_UNIX
+        if (!lib) {
+            /*
+             * If fullPath is a symbolic link, resolve the symbolic
+             * link and try again.
+             */
+            char* originalfullPath = loader_GetOriginalPathname(fullPath);
+            if (originalfullPath) {
+                PR_Free(fullPath);
+                fullPath = originalfullPath;
+                lib = loader_LoadLibInReferenceDir(fullPath, newShLibName);
+            }
+        }
+#endif
+        PR_Free(fullPath);
+    }
+    if (!lib) {
+#ifdef DEBUG_LOADER
+        PR_fprintf(PR_STDOUT, "\nAttempting to load %s\n", newShLibName);
+#endif
+        libSpec.type = PR_LibSpec_Pathname;
+        libSpec.value.pathname = newShLibName;
+        lib = PR_LoadLibraryWithFlags(libSpec, PR_LD_NOW | PR_LD_LOCAL);
+    }
+    if (NULL == lib) {
+#ifdef DEBUG_LOADER
+        PR_fprintf(PR_STDOUT, "\nLoading failed : %s.\n", newShLibName);
+#endif
+    }
+    return lib;
+}