Add sudo_unsetenv() and refactor private env syncing code into sync_env().

diff --git a/env.c b/env.c
index c1a71ea14924a7f8abe7c7bcec12742343e7b5b8..792111009a2299119de28ef9da0af701d40a0b4b 100644 (file)
--- a/env.c
+++ b/env.c
@@ -101,7 +101,11 @@ struct environment {
  */
 char **rebuild_env             __P((char **, int, int));
 void sudo_setenv               __P((const char *, const char *, int));
+void sudo_unsetenv             __P((const char *));
 static void insert_env         __P((char *, int));
+static void sync_env           __P((char **));
+
+extern char **environ;         /* global environment */
 
 /*
  * Copy of the sudo-managed environment.
@@ -206,6 +210,29 @@ static const char *initial_keepenv_table[] = {
     NULL
 };
 
+/*
+ * Syncronize our private copy of the environment with what is
+ * in envp.
+ */
+static void
+sync_env(envp)
+    char **envp;
+{
+    size_t evlen;
+    char **ep;
+
+    for (ep = envp; *ep != NULL; ep++)
+       continue;
+    evlen = ep - envp;
+    if (evlen + 1 > env.env_size) {
+       efree(env.envp);
+       env.env_size = evlen + 1 + 128;
+       env.envp = emalloc2(env.env_size, sizeof(char *));
+    }
+    memcpy(env.envp, envp, evlen + 1);
+    env.env_len = evlen;
+}
+
 /*
  * Similar to setenv(3) but operates on sudo's private copy of the environment
  * and it always overwrites.  The dupcheck param determines whether we need
@@ -223,16 +250,45 @@ sudo_setenv(var, val, dupcheck)
     esize = strlen(var) + 1 + strlen(val) + 1;
     estring = emalloc(esize);
 
+    /* Make sure we are operating on the current environment. */
+    if (env.envp != environ)
+       sync_env(environ);
+
+    /* Build environment string and insert it. */
     if (strlcpy(estring, var, esize) >= esize ||
        strlcat(estring, "=", esize) >= esize ||
        strlcat(estring, val, esize) >= esize) {
 
        errorx(1, "internal error, sudo_setenv() overflow");
     }
-
     insert_env(estring, dupcheck);
 }
 
+/*
+ * Similar to unsetenv(3) but operates on sudo's private copy of the
+ * environment.
+ */
+void
+sudo_unsetenv(var)
+    const char *var;
+{
+    char **nep;
+    size_t varlen;
+
+    /* Make sure we are operating on the current environment. */
+    if (env.envp != environ)
+       sync_env(environ);
+
+    varlen = strlen(var);
+    for (nep = env.envp; *nep; nep++) {
+       if (strncmp(var, *nep, varlen) == 0 && *nep[varlen] == '=') {
+           /* Found it; move everything over by one and update len. */
+           memmove(nep, nep + 1, env.env_len - (nep - env.envp));
+           env.env_len--;
+           return;
+       }
+    }
+}
 
 /*
  * Insert str into env.envp, assumes str has an '=' in it.
@@ -581,24 +637,9 @@ insert_env_vars(envp, env_vars)
     if (env_vars == NULL)
        return(envp);
 
-    /*
-     * Make sure we still own the environment and steal it back if not.
-     */
-    if (env.envp != envp) {
-       size_t evlen;
-       char **ep;
-
-       for (ep = envp; *ep != NULL; ep++)
-           continue;
-       evlen = ep - envp;
-       if (evlen + 1 > env.env_size) {
-           efree(env.envp);
-           env.env_size = evlen + 1 + 128;
-           env.envp = emalloc2(env.env_size, sizeof(char *));
-       }
-       memcpy(env.envp, envp, evlen + 1);
-       env.env_len = evlen;
-    }
+    /* Make sure we are operating on the current environment. */
+    if (env.envp != envp)
+       sync_env(envp);
 
     /* Add user-specified environment variables. */
     for (cur = env_vars; cur != NULL; cur = cur->next)

diff --git a/sudo.h b/sudo.h
index e9eb05e5b90b09ae8333a02079f130d6c49049cb..3b284935abfffef7e445140d8806d500dba3ef89 100644 (file)
--- a/sudo.h
+++ b/sudo.h
@@ -265,6 +265,7 @@ FILE *open_sudoers  __P((const char *, int *));
 void display_privs     __P((VOID *, struct passwd *));
 int display_cmnd       __P((VOID *, struct passwd *));
 void sudo_setenv       __P((const char *, const char *, int));
+void sudo_unsetenv     __P((const char *));
 void sudo_setgrent     __P((void));
 void sudo_endgrent     __P((void));
 void sudo_setpwent     __P((void));