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-rw-r--r--libpam/pam_env.c389
1 files changed, 389 insertions, 0 deletions
diff --git a/libpam/pam_env.c b/libpam/pam_env.c
new file mode 100644
index 00000000..a1e744b7
--- /dev/null
+++ b/libpam/pam_env.c
@@ -0,0 +1,389 @@
+/*
+ * pam_env.c
+ *
+ * Copyright (c) Andrew G. Morgan <morgan@parc.power.net> 1996,1997
+ * All rights reserved.
+ *
+ * This file was written from a "hint" provided by the people at SUN.
+ * and the X/Open XSSO draft of March 1997.
+ *
+ * $Id$
+ */
+
+#include <string.h>
+#include <stdlib.h>
+#ifdef sunos
+#define memmove(x,y,z) bcopy(y,x,z)
+#endif
+
+#include "pam_private.h"
+
+/* helper functions */
+
+#ifdef DEBUG
+static void _pam_dump_env(pam_handle_t *pamh)
+{
+ int i;
+
+ D(("Listing environment of pamh=%p", pamh));
+ D(("pamh->env = %p", pamh->env));
+ D(("environment entries used = %d [of %d allocated]"
+ , pamh->env->requested, pamh->env->entries));
+
+ for (i=0; i<pamh->env->requested; ++i) {
+ _pam_output_debug(">%-3d [%9p]:[%s]"
+ , i, pamh->env->list[i], pamh->env->list[i]);
+ }
+ _pam_output_debug("*NOTE* the last item should be (nil)");
+}
+#else
+#define _pam_dump_env(x)
+#endif
+
+/*
+ * Create the environment
+ */
+
+int _pam_make_env(pam_handle_t *pamh)
+{
+ D(("called."));
+ IF_NO_PAMH("_pam_make_env", pamh, PAM_ABORT);
+
+ /*
+ * get structure memory
+ */
+
+ pamh->env = (struct pam_environ *) malloc(sizeof(struct pam_environ));
+ if (pamh->env == NULL) {
+ _pam_system_log(LOG_CRIT, "_pam_make_env: out of memory");
+ return PAM_BUF_ERR;
+ }
+
+ /*
+ * get list memory
+ */
+
+ pamh->env->list = (char **)calloc( PAM_ENV_CHUNK, sizeof(char *) );
+ if (pamh->env->list == NULL) {
+ _pam_system_log(LOG_CRIT, "_pam_make_env: no memory for list");
+ _pam_drop(pamh->env);
+ return PAM_BUF_ERR;
+ }
+
+ /*
+ * fill entries in pamh->env
+ */
+
+ pamh->env->entries = PAM_ENV_CHUNK;
+ pamh->env->requested = 1;
+ pamh->env->list[0] = NULL;
+
+ _pam_dump_env(pamh); /* only active when debugging */
+
+ return PAM_SUCCESS;
+}
+
+/*
+ * purge the environment
+ */
+
+void _pam_drop_env(pam_handle_t *pamh)
+{
+ D(("called."));
+ IF_NO_PAMH("_pam_make_env", pamh, /* nothing to return */);
+
+ if (pamh->env != NULL) {
+ int i;
+ /* we will only purge the pamh->env->requested number of elements */
+
+ for (i=pamh->env->requested-1; i-- > 0; ) {
+ D(("dropping #%3d>%s<", i, pamh->env->list[i]));
+ _pam_overwrite(pamh->env->list[i]); /* clean */
+ _pam_drop(pamh->env->list[i]); /* forget */
+ }
+ pamh->env->requested = 0;
+ pamh->env->entries = 0;
+ _pam_drop(pamh->env->list); /* forget */
+ _pam_drop(pamh->env); /* forget */
+ } else {
+ D(("no environment present in pamh?"));
+ }
+}
+
+/*
+ * Return the item number of the given variable = first 'length' chars
+ * of 'name_value'. Since this is a static function, it is safe to
+ * assume its supplied arguments are well defined.
+ */
+
+static int _pam_search_env(const struct pam_environ *env
+ , const char *name_value, int length)
+{
+ int i;
+
+ for (i=env->requested-1; i-- > 0; ) {
+ if (strncmp(name_value,env->list[i],length) == 0
+ && env->list[i][length] == '=') {
+
+ return i; /* Got it! */
+
+ }
+ }
+
+ return -1; /* no luck */
+}
+
+/*
+ * externally visible functions
+ */
+
+/*
+ * pam_putenv(): Add/replace/delete a PAM-environment variable.
+ *
+ * Add/replace:
+ * name_value = "NAME=VALUE" or "NAME=" (for empty value="\0")
+ *
+ * delete:
+ * name_value = "NAME"
+ */
+
+int pam_putenv(pam_handle_t *pamh, const char *name_value)
+{
+ int l2eq, item, retval;
+
+ D(("called."));
+ IF_NO_PAMH("pam_putenv", pamh, PAM_ABORT);
+
+ if (name_value == NULL) {
+ _pam_system_log(LOG_ERR, "pam_putenv: no variable indicated");
+ return PAM_PERM_DENIED;
+ }
+
+ /*
+ * establish if we are setting or deleting; scan for '='
+ */
+
+ for (l2eq=0; name_value[l2eq] && name_value[l2eq] != '='; ++l2eq);
+ if (l2eq <= 0) {
+ _pam_system_log(LOG_ERR, "pam_putenv: bad variable");
+ return PAM_BAD_ITEM;
+ }
+
+ /*
+ * Look first for environment.
+ */
+
+ if (pamh->env == NULL || pamh->env->list == NULL) {
+ _pam_system_log(LOG_ERR, "pam_putenv: no env%s found",
+ pamh->env == NULL ? "":"-list");
+ return PAM_ABORT;
+ }
+
+ /* find the item to replace */
+
+ item = _pam_search_env(pamh->env, name_value, l2eq);
+
+ if (name_value[l2eq]) { /* (re)setting */
+
+ if (item == -1) { /* new variable */
+ D(("adding item: %s", name_value));
+ /* enough space? */
+ if (pamh->env->entries <= pamh->env->requested) {
+ register int i;
+ register char **tmp;
+
+ /* get some new space */
+ tmp = calloc( pamh->env->entries + PAM_ENV_CHUNK
+ , sizeof(char *) );
+ if (tmp == NULL) {
+ /* nothing has changed - old env intact */
+ _pam_system_log(LOG_CRIT,
+ "pam_putenv: cannot grow environment");
+ return PAM_BUF_ERR;
+ }
+
+ /* copy old env-item pointers/forget old */
+ for (i=0; i<pamh->env->requested; ++i) {
+ tmp[i] = pamh->env->list[i];
+ pamh->env->list[i] = NULL;
+ }
+
+ /* drop old list and replace with new */
+ _pam_drop(pamh->env->list);
+ pamh->env->list = tmp;
+ pamh->env->entries += PAM_ENV_CHUNK;
+
+ D(("resized env list"));
+ _pam_dump_env(pamh); /* only when debugging */
+ }
+
+ item = pamh->env->requested-1; /* old last item (NULL) */
+
+ /* add a new NULL entry at end; increase counter */
+ pamh->env->list[pamh->env->requested++] = NULL;
+
+ } else { /* replace old */
+ D(("replacing item: %s\n with: %s"
+ , pamh->env->list[item], name_value));
+ _pam_overwrite(pamh->env->list[item]);
+ _pam_drop(pamh->env->list[item]);
+ }
+
+ /*
+ * now we have a place to put the new env-item, insert at 'item'
+ */
+
+ pamh->env->list[item] = _pam_strdup(name_value);
+ if (pamh->env->list[item] != NULL) {
+ _pam_dump_env(pamh); /* only when debugging */
+ return PAM_SUCCESS;
+ }
+
+ /* something went wrong; we should delete the item - fall through */
+
+ retval = PAM_BUF_ERR; /* an error occurred */
+ } else {
+ retval = PAM_SUCCESS; /* we requested delete */
+ }
+
+ /* getting to here implies we are deleting an item */
+
+ if (item < 0) {
+ _pam_system_log(LOG_ERR, "pam_putenv: delete non-existent entry; %s",
+ name_value);
+ return PAM_BAD_ITEM;
+ }
+
+ /*
+ * remove item: purge memory; reset counter; resize [; display-env]
+ */
+
+ D(("deleting: env#%3d:[%s]", item, pamh->env->list[item]));
+ _pam_overwrite(pamh->env->list[item]);
+ _pam_drop(pamh->env->list[item]);
+ --(pamh->env->requested);
+ D(("mmove: item[%d]+%d -> item[%d]"
+ , item+1, ( pamh->env->requested - item ), item));
+ (void) memmove(&pamh->env->list[item], &pamh->env->list[item+1]
+ , ( pamh->env->requested - item )*sizeof(char *) );
+
+ _pam_dump_env(pamh); /* only when debugging */
+
+ /*
+ * deleted.
+ */
+
+ return retval;
+}
+
+/*
+ * Return the value of the requested environment variable
+ */
+
+const char *pam_getenv(pam_handle_t *pamh, const char *name)
+{
+ int item;
+
+ D(("called."));
+ IF_NO_PAMH("pam_getenv", pamh, NULL);
+
+ if (name == NULL) {
+ _pam_system_log(LOG_ERR, "pam_getenv: no variable indicated");
+ return NULL;
+ }
+
+ if (pamh->env == NULL || pamh->env->list == NULL) {
+ _pam_system_log(LOG_ERR, "pam_getenv: no env%s found",
+ pamh->env == NULL ? "":"-list" );
+ return NULL;
+ }
+
+ /* find the requested item */
+
+ item = _pam_search_env(pamh->env, name, strlen(name));
+ if (item != -1) {
+
+ D(("env-item: %s, found!", name));
+ return (pamh->env->list[item] + 1 + strlen(name));
+
+ } else {
+
+ D(("env-item: %s, not found", name));
+ return NULL;
+
+ }
+}
+
+static char **_copy_env(pam_handle_t *pamh)
+{
+ char **dump;
+ int i = pamh->env->requested; /* reckon size of environment */
+ char *const *env = pamh->env->list;
+
+ D(("now get some memory for dump"));
+
+ /* allocate some memory for this (plus the null tail-pointer) */
+ dump = (char **) calloc(i, sizeof(char *));
+ D(("dump = %p", dump));
+ if (dump == NULL) {
+ return NULL;
+ }
+
+ /* now run through entries and copy the variables over */
+ dump[--i] = NULL;
+ while (i-- > 0) {
+ D(("env[%d]=`%s'", i,env[i]));
+ dump[i] = _pam_strdup(env[i]);
+ D(("->dump[%d]=`%s'", i,dump[i]));
+ if (dump[i] == NULL) {
+ /* out of memory */
+
+ while (dump[++i]) {
+ _pam_overwrite(dump[i]);
+ _pam_drop(dump[i]);
+ }
+ return NULL;
+ }
+ }
+
+ env = NULL; /* forget now */
+
+ /* return transcribed environment */
+ return dump;
+}
+
+char **pam_getenvlist(pam_handle_t *pamh)
+{
+ int i;
+
+ D(("called."));
+ IF_NO_PAMH("pam_getenvlist", pamh, NULL);
+
+ if (pamh->env == NULL || pamh->env->list == NULL) {
+ _pam_system_log(LOG_ERR, "pam_getenvlist: no env%s found",
+ pamh->env == NULL ? "":"-list" );
+ return NULL;
+ }
+
+ /* some quick checks */
+
+ if (pamh->env->requested > pamh->env->entries) {
+ _pam_system_log(LOG_ERR, "pam_getenvlist: environment corruption");
+ _pam_dump_env(pamh); /* only active when debugging */
+ return NULL;
+ }
+
+ for (i=pamh->env->requested-1; i-- > 0; ) {
+ if (pamh->env->list[i] == NULL) {
+ _pam_system_log(LOG_ERR, "pam_getenvlist: environment broken");
+ _pam_dump_env(pamh); /* only active when debugging */
+ return NULL; /* somehow we've broken the environment!? */
+ }
+ }
+
+ /* Seems fine; copy environment */
+
+ _pam_dump_env(pamh); /* only active when debugging */
+
+ return _copy_env(pamh);
+}
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