X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fbus-proxyd%2Fbus-proxyd.c;h=4d0a265c6676bd3ea7bf477fa01b4dcd42ce283a;hb=d714387ed7003ce011a3ed0f1a604a7984a8a68d;hp=6da7fb9b55e1d89276f9888a2504ef7bfa49f0b2;hpb=3e0a2048978fcc7aff00797bdb876b2592c2fbc7;p=elogind.git diff --git a/src/bus-proxyd/bus-proxyd.c b/src/bus-proxyd/bus-proxyd.c index 6da7fb9b5..4d0a265c6 100644 --- a/src/bus-proxyd/bus-proxyd.c +++ b/src/bus-proxyd/bus-proxyd.c @@ -44,9 +44,10 @@ #include "strv.h" #include "def.h" #include "capability.h" -#include "bus-policy.h" #include "bus-control.h" #include "smack-util.h" +#include "set.h" +#include "bus-xml-policy.h" static char *arg_address = NULL; static char *arg_command_line_buffer = NULL; @@ -138,9 +139,9 @@ static int parse_argv(int argc, char *argv[]) { return log_oom(); #ifdef ENABLE_KDBUS - a = strjoin("x-container-kernel:machine=", e, ";x-container-unix:machine=", e, NULL); + a = strjoin("x-machine-kernel:machine=", e, ";x-machine-unix:machine=", e, NULL); #else - a = strjoin("x-container-unix:machine=", e, NULL); + a = strjoin("x-machine-unix:machine=", e, NULL); #endif if (!a) return log_oom(); @@ -188,7 +189,7 @@ static int rename_service(sd_bus *a, sd_bus *b) { assert(a); assert(b); - r = sd_bus_get_owner_creds(b, SD_BUS_CREDS_UID|SD_BUS_CREDS_PID|SD_BUS_CREDS_CMDLINE|SD_BUS_CREDS_COMM, &creds); + r = sd_bus_get_owner_creds(b, SD_BUS_CREDS_UID|SD_BUS_CREDS_PID|SD_BUS_CREDS_CMDLINE|SD_BUS_CREDS_COMM|SD_BUS_CREDS_AUGMENT, &creds); if (r < 0) return r; @@ -344,6 +345,17 @@ static int synthetic_reply_method_error(sd_bus_message *call, const sd_bus_error return synthetic_driver_send(call->bus, m); } +static int synthetic_reply_method_errorf(sd_bus_message *call, const char *name, const char *format, ...) { + _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL; + va_list ap; + + va_start(ap, format); + bus_error_setfv(&error, name, format, ap); + va_end(ap); + + return synthetic_reply_method_error(call, &error); +} + static int synthetic_reply_method_errno(sd_bus_message *call, int error, const sd_bus_error *p) { _cleanup_bus_error_free_ sd_bus_error berror = SD_BUS_ERROR_NULL; @@ -393,6 +405,9 @@ static int synthetic_reply_return_strv(sd_bus_message *call, char **l) { assert(call); + if (call->header->flags & BUS_MESSAGE_NO_REPLY_EXPECTED) + return 0; + r = sd_bus_message_new_method_return(call, &m); if (r < 0) return synthetic_reply_method_errno(call, r, NULL); @@ -962,7 +977,7 @@ static int process_driver(sd_bus *a, sd_bus *b, sd_bus_message *m, Policy *polic static int handle_policy_error(sd_bus_message *m, int r) { if (r == -ESRCH || r == -ENXIO) - return sd_bus_reply_method_errorf(m, SD_BUS_ERROR_NAME_HAS_NO_OWNER, "Name %s is currently not owned by anyone.", m->destination); + return synthetic_reply_method_errorf(m, SD_BUS_ERROR_NAME_HAS_NO_OWNER, "Name %s is currently not owned by anyone.", m->destination); return r; } @@ -993,6 +1008,24 @@ static int process_policy(sd_bus *from, sd_bus *to, sd_bus_message *m, Policy *p (void) sd_bus_creds_get_uid(&m->creds, &sender_uid); (void) sd_bus_creds_get_gid(&m->creds, &sender_gid); + if (sender_uid == UID_INVALID || sender_gid == GID_INVALID) { + _cleanup_bus_creds_unref_ sd_bus_creds *sender_creds = NULL; + + /* If the message came from another legacy + * client, then the message creds will be + * missing, simply because on legacy clients + * per-message creds were unknown. In this + * case, query the creds of the peer + * instead. */ + + r = bus_get_name_creds_kdbus(from, m->sender, SD_BUS_CREDS_UID|SD_BUS_CREDS_GID, true, &sender_creds); + if (r < 0) + return handle_policy_error(m, r); + + (void) sd_bus_creds_get_uid(sender_creds, &sender_uid); + (void) sd_bus_creds_get_gid(sender_creds, &sender_gid); + } + /* First check whether the sender can send the message to our name */ if (set_isempty(owned_names)) { if (policy_check_send(policy, sender_uid, sender_gid, m->header->type, NULL, m->path, m->interface, m->member)) @@ -1009,7 +1042,7 @@ static int process_policy(sd_bus *from, sd_bus *to, sd_bus_message *m, Policy *p } if (granted) { - /* Then check whether us (the recipient) can recieve from the sender's name */ + /* Then check whether us (the recipient) can receive from the sender's name */ if (strv_isempty(sender_names)) { if (policy_check_recv(policy, our_ucred->uid, our_ucred->gid, m->header->type, NULL, m->path, m->interface, m->member)) return 0; @@ -1025,7 +1058,7 @@ static int process_policy(sd_bus *from, sd_bus *to, sd_bus_message *m, Policy *p /* Return an error back to the caller */ if (m->header->type == SD_BUS_MESSAGE_METHOD_CALL) - return sd_bus_reply_method_errorf(m, SD_BUS_ERROR_ACCESS_DENIED, "Access prohibited by XML receiver policy."); + return synthetic_reply_method_errorf(m, SD_BUS_ERROR_ACCESS_DENIED, "Access prohibited by XML receiver policy."); /* Return 1, indicating that the message shall not be processed any further */ return 1; @@ -1114,7 +1147,7 @@ static int process_policy(sd_bus *from, sd_bus *to, sd_bus_message *m, Policy *p /* Return an error back to the caller */ if (m->header->type == SD_BUS_MESSAGE_METHOD_CALL) - return sd_bus_reply_method_errorf(m, SD_BUS_ERROR_ACCESS_DENIED, "Access prohibited by XML sender policy."); + return synthetic_reply_method_errorf(m, SD_BUS_ERROR_ACCESS_DENIED, "Access prohibited by XML sender policy."); /* Return 1, indicating that the message shall not be processed any further */ return 1; @@ -1267,6 +1300,7 @@ int main(int argc, char *argv[]) { _cleanup_free_ char *peersec = NULL; Policy policy_buffer = {}, *policy = NULL; _cleanup_set_free_free_ Set *owned_names = NULL; + uid_t original_uid; log_set_target(LOG_TARGET_JOURNAL_OR_KMSG); log_parse_environment(); @@ -1288,6 +1322,8 @@ int main(int argc, char *argv[]) { goto finish; } + original_uid = getuid(); + is_unix = sd_is_socket(in_fd, AF_UNIX, 0, 0) > 0 && sd_is_socket(out_fd, AF_UNIX, 0, 0) > 0; @@ -1429,7 +1465,11 @@ int main(int argc, char *argv[]) { policy = &policy_buffer; /* policy_dump(policy); */ - if (!policy_check_hello(policy, ucred.uid, ucred.gid)) { + if (ucred.uid == original_uid) + log_debug("Permitting access, since bus owner matches bus client."); + else if (policy_check_hello(policy, ucred.uid, ucred.gid)) + log_debug("Permitting access due to XML policy."); + else { r = log_error_errno(EPERM, "Policy denied connection."); goto finish; } @@ -1590,14 +1630,26 @@ int main(int argc, char *argv[]) { if (!processed) { k = sd_bus_send(b, m, NULL); if (k < 0) { - if (k == -ECONNRESET) + if (k == -ECONNRESET) { r = 0; - else { + goto finish; + } else if (k == -EPERM && m->reply_cookie > 0) { + /* If the peer tries to send a reply and it is rejected with EPERM + * by the kernel, we ignore the error. This catches cases where the + * original method-call didn't had EXPECT_REPLY set, but the proxy-peer + * still sends a reply. This is allowed in dbus1, but not in kdbus. We + * don't want to track reply-windows in the proxy, so we simply ignore + * EPERM for all replies. The only downside is, that callers are no + * longer notified if their replies are dropped. However, this is + * equivalent to the caller's timeout to expire, so this should be + * acceptable. Nobody sane sends replies without a matching method-call, + * so nobody should care. */ + r = 1; + } else { r = k; log_error_errno(r, "Failed to send message to client: %m"); + goto finish; } - - goto finish; } else r = 1; } @@ -1667,17 +1719,20 @@ int main(int argc, char *argv[]) { k = sd_bus_send(a, m, NULL); if (k < 0) { - if (k == -EREMCHG) + if (k == -EREMCHG) { /* The name database changed since the policy check, hence let's check again */ continue; - else if (k == -ECONNRESET) + } else if (k == -ECONNRESET) { r = 0; - else { + goto finish; + } else if (k == -EPERM && m->reply_cookie > 0) { + /* see above why EPERM is ignored for replies */ + r = 1; + } else { r = k; log_error_errno(r, "Failed to send message to bus: %m"); + goto finish; } - - goto finish; } else r = 1;