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Diffstat (limited to 'modules/pam_env/pam_env.c')
-rw-r--r--modules/pam_env/pam_env.c123
1 files changed, 66 insertions, 57 deletions
diff --git a/modules/pam_env/pam_env.c b/modules/pam_env/pam_env.c
index 3846e359..79d43722 100644
--- a/modules/pam_env/pam_env.c
+++ b/modules/pam_env/pam_env.c
@@ -1,6 +1,6 @@
-/* pam_env module */
-
/*
+ * pam_env module
+ *
* Written by Dave Kinchlea <kinch@kinch.ark.com> 1997/01/31
* Inspired by Andrew Morgan <morgan@kernel.org>, who also supplied the
* template for this file (via pam_mail)
@@ -10,7 +10,7 @@
#define DEFAULT_READ_ENVFILE 1
#define DEFAULT_USER_ENVFILE ".pam_environment"
-#define DEFAULT_USER_READ_ENVFILE 1
+#define DEFAULT_USER_READ_ENVFILE 0
#include "config.h"
@@ -26,22 +26,11 @@
#include <sys/types.h>
#include <unistd.h>
-/*
- * here, we make a definition for the externally accessible function
- * in this file (this definition is required for static a module
- * but strongly encouraged generally) it is used to instruct the
- * modules include file to define the function prototypes.
- */
-
-#define PAM_SM_AUTH /* This is primarily a AUTH_SETCRED module */
-#define PAM_SM_SESSION /* But I like to be friendly */
-#define PAM_SM_PASSWORD /* "" */
-#define PAM_SM_ACCOUNT /* "" */
-
#include <security/pam_modules.h>
#include <security/pam_modutil.h>
#include <security/_pam_macros.h>
#include <security/pam_ext.h>
+#include "pam_inline.h"
/* This little structure makes it easier to keep variables together */
@@ -52,7 +41,7 @@ typedef struct var {
char *override;
} VAR;
-#define BUF_SIZE 1024
+#define BUF_SIZE 8192
#define MAX_ENV 8192
#define GOOD_LINE 0
@@ -63,7 +52,7 @@ typedef struct var {
#define ILLEGAL_VAR 103
static int _assemble_line(FILE *, char *, int);
-static int _parse_line(const pam_handle_t *, char *, VAR *);
+static int _parse_line(const pam_handle_t *, const char *, VAR *);
static int _check_var(pam_handle_t *, VAR *); /* This is the real meat */
static void _clean_var(VAR *);
static int _expand_arg(pam_handle_t *, char **);
@@ -71,8 +60,8 @@ static const char * _pam_get_item_byname(pam_handle_t *, const char *);
static int _define_var(pam_handle_t *, int, VAR *);
static int _undefine_var(pam_handle_t *, int, VAR *);
-/* This is a flag used to designate an empty string */
-static char quote='Z';
+/* This is a special value used to designate an empty string */
+static char quote='\0';
/* argument parsing */
@@ -93,40 +82,41 @@ _pam_parse (const pam_handle_t *pamh, int argc, const char **argv,
/* step through arguments */
for (; argc-- > 0; ++argv) {
+ const char *str;
/* generic options */
if (!strcmp(*argv,"debug"))
ctrl |= PAM_DEBUG_ARG;
- else if (!strncmp(*argv,"conffile=",9)) {
- if ((*argv)[9] == '\0') {
+ else if ((str = pam_str_skip_prefix(*argv, "conffile=")) != NULL) {
+ if (str[0] == '\0') {
pam_syslog(pamh, LOG_ERR,
"conffile= specification missing argument - ignored");
} else {
- *conffile = 9+*argv;
+ *conffile = str;
D(("new Configuration File: %s", *conffile));
}
- } else if (!strncmp(*argv,"envfile=",8)) {
- if ((*argv)[8] == '\0') {
+ } else if ((str = pam_str_skip_prefix(*argv, "envfile=")) != NULL) {
+ if (str[0] == '\0') {
pam_syslog (pamh, LOG_ERR,
"envfile= specification missing argument - ignored");
} else {
- *envfile = 8+*argv;
+ *envfile = str;
D(("new Env File: %s", *envfile));
}
- } else if (!strncmp(*argv,"user_envfile=",13)) {
- if ((*argv)[13] == '\0') {
+ } else if ((str = pam_str_skip_prefix(*argv, "user_envfile=")) != NULL) {
+ if (str[0] == '\0') {
pam_syslog (pamh, LOG_ERR,
"user_envfile= specification missing argument - ignored");
} else {
- *user_envfile = 13+*argv;
+ *user_envfile = str;
D(("new User Env File: %s", *user_envfile));
}
- } else if (!strncmp(*argv,"readenv=",8))
- *readenv = atoi(8+*argv);
- else if (!strncmp(*argv,"user_readenv=",13))
- *user_readenv = atoi(13+*argv);
- else
+ } else if ((str = pam_str_skip_prefix(*argv, "readenv=")) != NULL) {
+ *readenv = atoi(str);
+ } else if ((str = pam_str_skip_prefix(*argv, "user_readenv=")) != NULL) {
+ *user_readenv = atoi(str);
+ } else
pam_syslog(pamh, LOG_ERR, "unknown option: %s", *argv);
}
@@ -228,9 +218,16 @@ _parse_env_file(pam_handle_t *pamh, int ctrl, const char *file)
mark[0] = '\0';
/*
- * sanity check, the key must be alpha-numeric
+ * sanity check, the key must be alphanumeric
*/
+ if (key[0] == '=') {
+ pam_syslog(pamh, LOG_ERR,
+ "missing key name '%s' in %s', ignoring",
+ key, file);
+ continue;
+ }
+
for ( i = 0 ; key[i] != '=' && key[i] != '\0' ; i++ )
if (!isalnum(key[i]) && key[i] != '_') {
pam_syslog(pamh, LOG_ERR,
@@ -282,7 +279,7 @@ _parse_env_file(pam_handle_t *pamh, int ctrl, const char *file)
/*
* This is where we read a line of the PAM config file. The line may be
- * preceeded by lines of comments and also extended with "\\\n"
+ * preceded by lines of comments and also extended with "\\\n"
*/
static int _assemble_line(FILE *f, char *buffer, int buf_len)
@@ -310,6 +307,14 @@ static int _assemble_line(FILE *f, char *buffer, int buf_len)
return 0;
}
}
+ if (p[0] == '\0') {
+ D(("_assemble_line: corrupted or binary file"));
+ return -1;
+ }
+ if (p[strlen(p)-1] != '\n') {
+ D(("_assemble_line: line too long"));
+ return -1;
+ }
/* skip leading spaces --- line may be blank */
@@ -366,7 +371,7 @@ static int _assemble_line(FILE *f, char *buffer, int buf_len)
}
static int
-_parse_line (const pam_handle_t *pamh, char *buffer, VAR *var)
+_parse_line (const pam_handle_t *pamh, const char *buffer, VAR *var)
{
/*
* parse buffer into var, legal syntax is
@@ -377,7 +382,8 @@ _parse_line (const pam_handle_t *pamh, char *buffer, VAR *var)
*/
int length, quoteflg=0;
- char *ptr, **valptr, *tmpptr;
+ const char *ptr, *tmpptr;
+ char **valptr;
D(("Called buffer = <%s>", buffer));
@@ -405,12 +411,12 @@ _parse_line (const pam_handle_t *pamh, char *buffer, VAR *var)
while ((length = strspn(ptr, " \t")) > 0) {
ptr += length; /* remove leading whitespace */
D((ptr));
- if (strncmp(ptr,"DEFAULT=",8) == 0) {
- ptr+=8;
+ if ((tmpptr = pam_str_skip_prefix(ptr, "DEFAULT=")) != NULL) {
+ ptr = tmpptr;
D(("Default arg found: <%s>", ptr));
valptr=&(var->defval);
- } else if (strncmp(ptr, "OVERRIDE=", 9) == 0) {
- ptr+=9;
+ } else if ((tmpptr = pam_str_skip_prefix(ptr, "OVERRIDE=")) != NULL) {
+ ptr = tmpptr;
D(("Override arg found: <%s>", ptr));
valptr=&(var->override);
} else {
@@ -500,7 +506,7 @@ static int _check_var(pam_handle_t *pamh, VAR *var)
/* Now its easy */
- if (var->override && *(var->override) && &quote != var->override) {
+ if (var->override && *(var->override)) {
/* if there is a non-empty string in var->override, we use it */
D(("OVERRIDE variable <%s> being used: <%s>", var->name, var->override));
var->value = var->override;
@@ -513,7 +519,6 @@ static int _check_var(pam_handle_t *pamh, VAR *var)
* This means that the empty string was given for defval value
* which indicates that a variable should be defined with no value
*/
- *var->defval = '\0';
D(("An empty variable: <%s>", var->name));
retval = DEFINE_VAR;
} else if (var->defval) {
@@ -543,9 +548,11 @@ static int _expand_arg(pam_handle_t *pamh, char **value)
/* I know this shouldn't be hard-coded but it's so much easier this way */
char tmp[MAX_ENV];
+ size_t idx;
D(("Remember to initialize tmp!"));
memset(tmp, 0, MAX_ENV);
+ idx = 0;
/*
* (possibly non-existent) environment variables can be used as values
@@ -563,8 +570,8 @@ static int _expand_arg(pam_handle_t *pamh, char **value)
pam_syslog(pamh, LOG_ERR,
"Unrecognized escaped character: <%c> - ignoring",
*orig);
- } else if ((strlen(tmp) + 1) < MAX_ENV) {
- tmp[strlen(tmp)] = *orig++; /* Note the increment */
+ } else if (idx + 1 < MAX_ENV) {
+ tmp[idx++] = *orig++; /* Note the increment */
} else {
/* is it really a good idea to try to log this? */
D(("Variable buffer overflow: <%s> + <%s>", tmp, tmpptr));
@@ -580,8 +587,8 @@ static int _expand_arg(pam_handle_t *pamh, char **value)
" <%s> - ignoring", orig));
pam_syslog(pamh, LOG_ERR, "Expandable variables must be wrapped in {}"
" <%s> - ignoring", orig);
- if ((strlen(tmp) + 1) < MAX_ENV) {
- tmp[strlen(tmp)] = *orig++; /* Note the increment */
+ if (idx + 1 < MAX_ENV) {
+ tmp[idx++] = *orig++; /* Note the increment */
}
continue;
} else {
@@ -625,8 +632,10 @@ static int _expand_arg(pam_handle_t *pamh, char **value)
} /* switch */
if (tmpptr) {
- if ((strlen(tmp) + strlen(tmpptr)) < MAX_ENV) {
- strcat(tmp, tmpptr);
+ size_t len = strlen(tmpptr);
+ if (idx + len < MAX_ENV) {
+ strcpy(tmp + idx, tmpptr);
+ idx += len;
} else {
/* is it really a good idea to try to log this? */
D(("Variable buffer overflow: <%s> + <%s>", tmp, tmpptr));
@@ -637,8 +646,8 @@ static int _expand_arg(pam_handle_t *pamh, char **value)
}
} /* if ('{' != *orig++) */
} else { /* if ( '$' == *orig || '@' == *orig) */
- if ((strlen(tmp) + 1) < MAX_ENV) {
- tmp[strlen(tmp)] = *orig++; /* Note the increment */
+ if (idx + 1 < MAX_ENV) {
+ tmp[idx++] = *orig++; /* Note the increment */
} else {
/* is it really a good idea to try to log this? */
D(("Variable buffer overflow: <%s> + <%s>", tmp, tmpptr));
@@ -649,17 +658,17 @@ static int _expand_arg(pam_handle_t *pamh, char **value)
}
} /* for (;*orig;) */
- if (strlen(tmp) > strlen(*value)) {
+ if (idx > strlen(*value)) {
free(*value);
- if ((*value = malloc(strlen(tmp) +1)) == NULL) {
- D(("Couldn't malloc %d bytes for expanded var", strlen(tmp)+1));
+ if ((*value = malloc(idx + 1)) == NULL) {
+ D(("Couldn't malloc %d bytes for expanded var", idx + 1));
pam_syslog (pamh, LOG_CRIT, "Couldn't malloc %lu bytes for expanded var",
- (unsigned long)strlen(tmp)+1);
+ (unsigned long)idx+1);
return PAM_BUF_ERR;
}
}
strcpy(*value, tmp);
- memset(tmp,'\0',sizeof(tmp));
+ memset(tmp, '\0', sizeof(tmp));
D(("Exit."));
return PAM_SUCCESS;
@@ -699,7 +708,7 @@ static const char * _pam_get_item_byname(pam_handle_t *pamh, const char *name)
if (itemval && (strcmp(name, "HOME") == 0 || strcmp(name, "SHELL") == 0)) {
struct passwd *user_entry;
- user_entry = pam_modutil_getpwnam (pamh, (char *) itemval);
+ user_entry = pam_modutil_getpwnam (pamh, itemval);
if (!user_entry) {
pam_syslog(pamh, LOG_ERR, "No such user!?");
return NULL;
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-26 11:59:45 +0000