diff options
| -rw-r--r-- | common/smtppass.c | 62 | ||||
| -rw-r--r-- | common/sppriv.h | 1 |
2 files changed, 59 insertions, 4 deletions
diff --git a/common/smtppass.c b/common/smtppass.c index 0038d9e..c2d2136 100644 --- a/common/smtppass.c +++ b/common/smtppass.c @@ -52,6 +52,7 @@ #include <err.h> #include <paths.h> #include <stdarg.h> +#include <pwd.h> #include "usuals.h" @@ -129,7 +130,7 @@ spthread_t; * - Be sure that your configuration option needs to go into this * file. More likely it'll go into clamsmtpd.c * - When adding configuration options follow the instructions in - * clamsmtpd.c, except add option to spstate_t (above) and parse in + * clamsmtpd.c, except add option to spstate_t (sppriv.h) and parse in * sp_parse_option (below) */ @@ -139,7 +140,7 @@ spthread_t; #define CFG_LISTENADDR "Listen" #define CFG_TRANSPARENT "TransparentProxy" #define CFG_DIRECTORY "TempDirectory" - +#define CFG_USER "User" /* ----------------------------------------------------------------------- * DEFAULT SETTINGS @@ -156,7 +157,7 @@ spthread_t; spstate_t g_state; /* The state and configuration of the daemon */ unsigned int g_unique_id = 0x00100000; /* For connection ids */ -pthread_mutex_t g_mutex; /* The main mutex */ +pthread_mutex_t g_mutex; /* The main mutex */ pthread_mutexattr_t g_mtxattr; @@ -165,6 +166,7 @@ pthread_mutexattr_t g_mtxattr; */ static void on_quit(int signal); +static void drop_privileges(); static void pid_file(const char* pidfile, int write); static void connection_loop(int sock); static void* thread_main(void* arg); @@ -242,6 +244,9 @@ int sp_run(const char* configfile, const char* pidfile, int dbg_level) sp_messagex(NULL, LOG_DEBUG, "starting up..."); + /* Drop privileges before daemonizing */ + drop_privileges(); + /* When set to this we daemonize */ if(g_state.debug_level == -1) { @@ -342,6 +347,47 @@ static void on_quit(int signal) g_state.quit = 1; } +static void drop_privileges() +{ + char* t; + struct passwd* pw; + uid_t uid; + + if(g_state.user) + { + if(geteuid() != 0) + { + sp_messagex(NULL, LOG_WARNING, "must be started as root to switch to user: %s", g_state.user); + return; + } + + uid = strtol(g_state.user, &t, 10); + if(!t[0]) /* successful parse */ + pw = getpwuid(uid); + else /* must be a name */ + pw = getpwnam(g_state.user); + + if(pw == NULL) + errx(1, "couldn't look up user: %s", g_state.user); + + if(setgid(pw->pw_gid) == -1) + err(1, "unable to switch group: %d", pw->pw_gid); + + if(setuid(pw->pw_uid) == -1) + err(1, "unable to switch user: %d", pw->pw_uid); + + /* A paranoia check */ + if(setreuid(-1, 0) == 0) + err(1, "unable to completely drop privileges"); + + sp_messagex(NULL, LOG_DEBUG, "switched to user %s (uid %d, gid %d)", g_state.user, pw->pw_uid, pw->pw_gid); + } + + if(geteuid() == 0) + sp_messagex(NULL, LOG_WARNING, "running as root is NOT recommended"); +} + + static void pid_file(const char* pidfile, int write) { if(write) @@ -1413,6 +1459,14 @@ int sp_parse_option(const char* name, const char* value) ret = 1; } + else if(strcasecmp(CFG_USER, name) == 0) + { + if(strlen(value) == 0) + errx(2, "invalid setting: " CFG_USER); + g_state.user = value; + ret = 1; + } + /* Always pass through to program */ if(cb_parse_option(name, value) == 1) ret = 1; @@ -1457,7 +1511,7 @@ static int parse_config_file(const char* configfile) /* Double null terminate the data */ p = g_state._p; - p[len] = 0; + p[len] = '\n'; p[len + 1] = 0; n = g_state._p; diff --git a/common/sppriv.h b/common/sppriv.h index 89a89f9..30686f9 100644 --- a/common/sppriv.h +++ b/common/sppriv.h @@ -49,6 +49,7 @@ typedef struct spstate struct timeval timeout; /* Timeout for communication */ int transparent; /* Transparent proxying */ const char* directory; /* The temp directory */ + const char* user; /* User to run as */ struct sockaddr_any outaddr; /* The outgoing address */ const char* outname; |