X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fbus-proxyd%2Fbus-proxyd.c;h=d6607edfd6513ed10852a0789ed02684a8a1316f;hb=ed6d629a3487105e31415db9e175dd698ac20125;hp=2f26f81a366ba3136e169d469ee55e9b504448bb;hpb=f0a4c7391c7c682b658974b82390d332197740e2;p=elogind.git diff --git a/src/bus-proxyd/bus-proxyd.c b/src/bus-proxyd/bus-proxyd.c index 2f26f81a3..d6607edfd 100644 --- a/src/bus-proxyd/bus-proxyd.c +++ b/src/bus-proxyd/bus-proxyd.c @@ -311,48 +311,6 @@ static int synthesize_name_acquired(sd_bus *a, sd_bus *b, sd_bus_message *m) { return sd_bus_send(b, n, NULL); } -static int process_policy(sd_bus *a, sd_bus *b, sd_bus_message *m) { - _cleanup_bus_message_unref_ sd_bus_message *n = NULL; - int r; - - assert(a); - assert(b); - assert(m); - - if (!a->is_kernel) - return 0; - - if (!sd_bus_message_is_method_call(m, "org.freedesktop.DBus.Properties", "GetAll")) - return 0; - - if (!streq_ptr(m->path, "/org/gnome/DisplayManager/Slave")) - return 0; - - r = sd_bus_message_new_method_errorf(m, &n, SD_BUS_ERROR_ACCESS_DENIED, "gdm, you are stupid"); - if (r < 0) - return r; - - r = bus_message_append_sender(n, "org.freedesktop.DBus"); - if (r < 0) { - log_error("Failed to append sender to gdm reply: %s", strerror(-r)); - return r; - } - - r = bus_seal_synthetic_message(b, n); - if (r < 0) { - log_error("Failed to seal gdm reply: %s", strerror(-r)); - return r; - } - - r = sd_bus_send(b, n, NULL); - if (r < 0) { - log_error("Failed to send gdm reply: %s", strerror(-r)); - return r; - } - - return 1; -} - static int synthetic_driver_send(sd_bus *b, sd_bus_message *m) { int r; @@ -509,6 +467,94 @@ static int peer_is_privileged(sd_bus *bus, sd_bus_message *m) { return false; } +static int process_policy(sd_bus *a, sd_bus *b, sd_bus_message *m, Policy *policy, const struct ucred *ucred) { + int r; + char **name; + char **names_strv; + bool granted = false; + Iterator i; + + assert(a); + assert(b); + assert(m); + + if (!policy) + return 0; + + if (b->is_kernel) { + + /* The message came from the kernel, and is sent to our legacy client. */ + r = sd_bus_creds_get_well_known_names(&m->creds, &names_strv); + if (r < 0) + return r; + + STRV_FOREACH(name, names_strv) { + if (policy_check_send(policy, ucred, m->header->type, *name, m->path, m->interface, m->member)) { + r = free_and_strdup(&m->destination_ptr, *name); + if (r < 0) + break; + + granted = true; + break; + } + } + + if (r < 0) + return r; + + if (!granted) + return -EPERM; + + granted = false; + + HASHMAP_FOREACH(name, names_hash, i) { + if (policy_check_recv(policy, ucred, m->header->type, *name, m->path, m->interface, m->member)) + return 0; + } + + return -EPERM; + } else { + sd_bus_creds *bus_creds; + + /* The message came from the legacy client, and is sent to kdbus. */ + r = sd_bus_get_name_creds(a, m->destination, SD_BUS_CREDS_WELL_KNOWN_NAMES, &bus_creds); + if (r < 0) + return r; + + STRV_FOREACH(name, names_strv) { + if (policy_check_send(policy, ucred, m->header->type, *name, m->path, m->interface, m->member)) { + r = free_and_strdup(&m->destination_ptr, *name); + if (r < 0) + break; + + r = bus_kernel_parse_unique_name(m->sender, &m->verify_destination_id); + if (r < 0) + break; + + granted = true; + break; + } + } + + if (r < 0) + return r; + + if (!granted) + return -EPERM; + + granted = false; + + HASHMAP_FOREACH(name, names_hash, i) { + if (policy_check_recv(policy, ucred, m->header->type, *name, m->path, m->interface, m->member)) + return 0; + } + + return -EPERM; + } + + return 0; +} + static int process_driver(sd_bus *a, sd_bus *b, sd_bus_message *m, Policy *policy, const struct ucred *ucred) { int r; @@ -859,7 +905,7 @@ static int process_driver(sd_bus *a, sd_bus *b, sd_bus_message *m, Policy *polic if (r < 0) return synthetic_reply_method_errno(m, r, NULL); - if (!policy_check_own(policy, ucred, name)) + if (policy && !policy_check_own(policy, ucred, name)) return synthetic_reply_method_errno(m, -EPERM, NULL); if (!service_name_is_valid(name)) @@ -1032,7 +1078,7 @@ static int process_hello(sd_bus *a, sd_bus *b, sd_bus_message *m, Policy *policy return -EIO; } - if (!policy_check_hello(policy, ucred)) { + if (policy && !policy_check_hello(policy, ucred)) { log_error("Policy denied HELLO"); return -EPERM; } @@ -1143,6 +1189,7 @@ static int patch_sender(sd_bus *a, sd_bus_message *m) { int main(int argc, char *argv[]) { + _cleanup_bus_creds_unref_ sd_bus_creds *bus_creds = NULL; _cleanup_bus_close_unref_ sd_bus *a = NULL, *b = NULL; sd_id128_t server_id; int r, in_fd, out_fd; @@ -1261,6 +1308,12 @@ int main(int argc, char *argv[]) { goto finish; } + r = sd_bus_get_owner_creds(a, SD_BUS_CREDS_UID, &bus_creds); + if (r < 0) { + log_error("Failed to get bus creds: %s", strerror(-r)); + goto finish; + } + r = sd_bus_new(&b); if (r < 0) { log_error("Failed to allocate bus: %s", strerror(-r)); @@ -1420,13 +1473,21 @@ int main(int argc, char *argv[]) { } if (m) { + Policy *p = NULL; + uid_t uid; + + assert_se(sd_bus_creds_get_uid(bus_creds, &uid) == 0); + + if (uid == 0 || uid != ucred.uid) + p = &policy; + /* We officially got EOF, let's quit */ if (sd_bus_message_is_signal(m, "org.freedesktop.DBus.Local", "Disconnected")) { r = 0; goto finish; } - k = process_hello(a, b, m, &policy, &ucred, &got_hello); + k = process_hello(a, b, m, p, &ucred, &got_hello); if (k < 0) { r = k; log_error("Failed to process HELLO: %s", strerror(-r)); @@ -1436,14 +1497,7 @@ int main(int argc, char *argv[]) { if (k > 0) r = k; else { - k = process_policy(a, b, m); - if (k < 0) { - r = k; - log_error("Failed to process policy: %s", strerror(-r)); - goto finish; - } - - k = process_driver(a, b, m, &policy, &ucred); + k = process_driver(a, b, m, p, &ucred); if (k < 0) { r = k; log_error("Failed to process driver calls: %s", strerror(-r)); @@ -1453,17 +1507,33 @@ int main(int argc, char *argv[]) { if (k > 0) r = k; else { - k = sd_bus_send(a, m, NULL); - if (k < 0) { - if (k == -ECONNRESET) - r = 0; - else { + bool retry; + + do { + retry = false; + + k = process_policy(a, b, m, p, &ucred); + if (k < 0) { r = k; - log_error("Failed to send message: %s", strerror(-r)); + log_error("Failed to process policy: %s", strerror(-r)); + goto finish; } - goto finish; - } + k = sd_bus_send(a, m, NULL); + if (k < 0) { + if (k == -ECONNRESET) + r = 0; + else if (k == -EREMCHG) + retry = true; + else { + r = k; + log_error("Failed to send message: %s", strerror(-r)); + } + + if (!retry) + goto finish; + } + } while (retry); } } }