X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fpam-module.c;h=54a7b451e8b540de180395aee9305e3f9e09035f;hp=69b9b0ce78590dab1f410d3c12c027e70f1ae5b4;hb=74fe1fe36e35a26d764f1e3119d5f6d014db573c;hpb=35d2e7ec19f8d3960a14dc04642060ccee3faa43 diff --git a/src/pam-module.c b/src/pam-module.c index 69b9b0ce7..54a7b451e 100644 --- a/src/pam-module.c +++ b/src/pam-module.c @@ -1,4 +1,4 @@ -/*-*- Mode: C; c-basic-offset: 8 -*-*/ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. @@ -31,20 +31,21 @@ #include #include -#include - #include "util.h" #include "cgroup-util.h" #include "macro.h" #include "sd-daemon.h" +#include "strv.h" static int parse_argv(pam_handle_t *handle, int argc, const char **argv, bool *create_session, bool *kill_session, - bool *kill_user) { + bool *kill_user, + char ***controllers) { unsigned i; + bool controller_set = false; assert(argc >= 0); assert(argc == 0 || argv); @@ -60,6 +61,7 @@ static int parse_argv(pam_handle_t *handle, if (create_session) *create_session = k; + } else if (startswith(argv[i], "kill-session=")) { if ((k = parse_boolean(argv[i] + 13)) < 0) { pam_syslog(handle, LOG_ERR, "Failed to parse kill-session= argument."); @@ -77,12 +79,43 @@ static int parse_argv(pam_handle_t *handle, if (kill_user) *kill_user = k; + + } else if (startswith(argv[i], "controllers=")) { + + if (controllers) { + char **l; + + if (!(l = strv_split(argv[i] + 12, ","))) { + pam_syslog(handle, LOG_ERR, "Out of memory."); + return -ENOMEM; + } + + strv_free(*controllers); + *controllers = l; + } + + controller_set = true; + } else { pam_syslog(handle, LOG_ERR, "Unknown parameter '%s'.", argv[i]); return -EINVAL; } } + if (!controller_set && controllers) { + char **l; + + if (!(l = strv_new("cpu", NULL))) { + pam_syslog(handle, LOG_ERR, "Out of memory"); + return -ENOMEM; + } + + *controllers = l; + } + + if (controllers) + strv_remove(*controllers, "name=systemd"); + if (kill_session && *kill_session && kill_user) *kill_user = true; @@ -130,7 +163,7 @@ static uint64_t get_session_id(int *mode) { r = safe_atou32(s, &u); free(s); - if (r >= 0 && u != (uint32_t) -1) { + if (r >= 0 && u != (uint32_t) -1 && u > 0) { *mode = SESSION_ID_AUDIT; return (uint64_t) u; } @@ -181,53 +214,89 @@ static int get_user_data( const char **ret_username, struct passwd **ret_pw) { - const char *username; - struct passwd *pw; + const char *username = NULL; + struct passwd *pw = NULL; int r; + bool have_loginuid = false; + char *s; assert(handle); assert(ret_username); assert(ret_pw); - if ((r = pam_get_user(handle, &username, NULL)) != PAM_SUCCESS) { - pam_syslog(handle, LOG_ERR, "Failed to get user name."); - return r; + if (read_one_line_file("/proc/self/loginuid", &s) >= 0) { + uint32_t u; + + r = safe_atou32(s, &u); + free(s); + + if (r >= 0 && u != (uint32_t) -1 && u > 0) { + have_loginuid = true; + pw = pam_modutil_getpwuid(handle, u); + } } - if (!username || !*username) { - pam_syslog(handle, LOG_ERR, "User name not valid."); - return PAM_AUTH_ERR; + if (!have_loginuid) { + if ((r = pam_get_user(handle, &username, NULL)) != PAM_SUCCESS) { + pam_syslog(handle, LOG_ERR, "Failed to get user name."); + return r; + } + + if (!username || !*username) { + pam_syslog(handle, LOG_ERR, "User name not valid."); + return PAM_AUTH_ERR; + } + + pw = pam_modutil_getpwnam(handle, username); } - if (!(pw = pam_modutil_getpwnam(handle, username))) { + if (!pw) { pam_syslog(handle, LOG_ERR, "Failed to get user data."); return PAM_USER_UNKNOWN; } *ret_pw = pw; - *ret_username = username; + *ret_username = username ? username : pw->pw_name; return PAM_SUCCESS; } -static int create_user_group(pam_handle_t *handle, const char *group, struct passwd *pw, bool attach) { +static int create_user_group( + pam_handle_t *handle, + const char *controller, + const char *group, + struct passwd *pw, + bool attach, + bool remember) { + int r; assert(handle); assert(group); if (attach) - r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, group, 0); + r = cg_create_and_attach(controller, group, 0); else - r = cg_create(SYSTEMD_CGROUP_CONTROLLER, group); + r = cg_create(controller, group); if (r < 0) { pam_syslog(handle, LOG_ERR, "Failed to create cgroup: %s", strerror(-r)); return PAM_SESSION_ERR; } - if ((r = cg_set_task_access(SYSTEMD_CGROUP_CONTROLLER, group, 0755, pw->pw_uid, pw->pw_gid)) < 0 || - (r = cg_set_group_access(SYSTEMD_CGROUP_CONTROLLER, group, 0755, pw->pw_uid, pw->pw_gid)) < 0) { + if (r > 0 && remember) { + /* Remember that it was us who created this group, and + * that hence we need to remove it too. This is a + * protection against removing the cgroup when run + * recursively. */ + if ((r = pam_set_data(handle, "systemd.created", INT_TO_PTR(1), NULL)) != PAM_SUCCESS) { + pam_syslog(handle, LOG_ERR, "Failed to install created variable."); + return r; + } + } + + if ((r = cg_set_task_access(controller, group, 0644, pw->pw_uid, pw->pw_gid)) < 0 || + (r = cg_set_group_access(controller, group, 0755, pw->pw_uid, pw->pw_gid)) < 0) { pam_syslog(handle, LOG_ERR, "Failed to change access modes: %s", strerror(-r)); return PAM_SESSION_ERR; } @@ -246,18 +315,19 @@ _public_ PAM_EXTERN int pam_sm_open_session( char *buf = NULL; int lock_fd = -1; bool create_session = true; + char **controllers = NULL, **c; assert(handle); - pam_syslog(handle, LOG_INFO, "pam-systemd initializing"); - - if (parse_argv(handle, argc, argv, &create_session, NULL, NULL) < 0) - return PAM_SESSION_ERR; + /* pam_syslog(handle, LOG_DEBUG, "pam-systemd initializing"); */ /* Make this a NOP on non-systemd systems */ if (sd_booted() <= 0) return PAM_SUCCESS; + if (parse_argv(handle, argc, argv, &create_session, NULL, NULL, &controllers) < 0) + return PAM_SESSION_ERR; + if ((r = get_user_data(handle, &username, &pw)) != PAM_SUCCESS) goto finish; @@ -326,16 +396,23 @@ _public_ PAM_EXTERN int pam_sm_open_session( r = asprintf(&buf, "/user/%s/%s", username, id); } else - r = asprintf(&buf, "/user/%s/no-session", username); + r = asprintf(&buf, "/user/%s/master", username); if (r < 0) { r = PAM_BUF_ERR; goto finish; } - if ((r = create_user_group(handle, buf, pw, true)) != PAM_SUCCESS) + pam_syslog(handle, LOG_INFO, "Moving new user session for %s into control group %s.", username, buf); + + if ((r = create_user_group(handle, SYSTEMD_CGROUP_CONTROLLER, buf, pw, true, true)) != PAM_SUCCESS) goto finish; + /* The additional controllers don't really matter, so we + * ignore the return value */ + STRV_FOREACH(c, controllers) + create_user_group(handle, *c, buf, pw, true, false); + r = PAM_SUCCESS; finish: @@ -344,6 +421,8 @@ finish: if (lock_fd >= 0) close_nointr_nofail(lock_fd); + strv_free(controllers); + return r; } @@ -358,7 +437,7 @@ static int session_remains(pam_handle_t *handle, const char *user_path) { while ((r = cg_read_subgroup(d, &subgroup)) > 0) { - remains = !streq(subgroup, "no-session"); + remains = !streq(subgroup, "master"); free(subgroup); if (remains) @@ -385,16 +464,18 @@ _public_ PAM_EXTERN int pam_sm_close_session( char *session_path = NULL, *nosession_path = NULL, *user_path = NULL; const char *id; struct passwd *pw; + const void *created = NULL; + char **controllers = NULL, **c; assert(handle); - if (parse_argv(handle, argc, argv, NULL, &kill_session, &kill_user) < 0) - return PAM_SESSION_ERR; - /* Make this a NOP on non-systemd systems */ if (sd_booted() <= 0) return PAM_SUCCESS; + if (parse_argv(handle, argc, argv, NULL, &kill_session, &kill_user, &controllers) < 0) + return PAM_SESSION_ERR; + if ((r = get_user_data(handle, &username, &pw)) != PAM_SUCCESS) goto finish; @@ -404,37 +485,54 @@ _public_ PAM_EXTERN int pam_sm_close_session( goto finish; } - /* We are probably still in some session/no-session dir. Move ourselves out of the way as first step */ + /* We are probably still in some session/user dir. Move ourselves out of the way as first step */ if ((r = cg_attach(SYSTEMD_CGROUP_CONTROLLER, "/user", 0)) < 0) pam_syslog(handle, LOG_ERR, "Failed to move us away: %s", strerror(-r)); + STRV_FOREACH(c, controllers) + if ((r = cg_attach(*c, "/user", 0)) < 0) + pam_syslog(handle, LOG_ERR, "Failed to move us away in %s hierarchy: %s", *c, strerror(-r)); + if (asprintf(&user_path, "/user/%s", username) < 0) { r = PAM_BUF_ERR; goto finish; } - if ((id = pam_getenv(handle, "XDG_SESSION_ID"))) { + pam_get_data(handle, "systemd.created", &created); + + if ((id = pam_getenv(handle, "XDG_SESSION_ID")) && created) { if (asprintf(&session_path, "/user/%s/%s", username, id) < 0 || - asprintf(&nosession_path, "/user/%s/no-session", username) < 0) { + asprintf(&nosession_path, "/user/%s/master", username) < 0) { r = PAM_BUF_ERR; goto finish; } if (kill_session) { + pam_syslog(handle, LOG_INFO, "Killing remaining processes of user session %s of %s.", id, username); + /* Kill processes in session cgroup, and delete it */ if ((r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, session_path, true)) < 0) pam_syslog(handle, LOG_ERR, "Failed to kill session cgroup: %s", strerror(-r)); } else { - /* Migrate processes from session to - * no-session cgroup. First, try to create the - * no-session group in case it doesn't exist - * yet. Also, delete the session group. */ - create_user_group(handle, nosession_path, pw, 0); + pam_syslog(handle, LOG_INFO, "Moving remaining processes of user session %s of %s into control group %s.", id, username, nosession_path); + + /* Migrate processes from session to user + * cgroup. First, try to create the user group + * in case it doesn't exist yet. Also, delete + * the session group. */ + create_user_group(handle, SYSTEMD_CGROUP_CONTROLLER, nosession_path, pw, false, false); if ((r = cg_migrate_recursive(SYSTEMD_CGROUP_CONTROLLER, session_path, nosession_path, false, true)) < 0) pam_syslog(handle, LOG_ERR, "Failed to migrate session cgroup: %s", strerror(-r)); } + + STRV_FOREACH(c, controllers) { + create_user_group(handle, *c, nosession_path, pw, false, false); + + if ((r = cg_migrate_recursive(*c, session_path, nosession_path, false, true)) < 0) + pam_syslog(handle, LOG_ERR, "Failed to migrate session cgroup in hierarchy %s: %s", *c, strerror(-r)); + } } /* GC user tree */ @@ -446,7 +544,7 @@ _public_ PAM_EXTERN int pam_sm_close_session( /* Kill user processes not attached to any session */ if (kill_user && r == 0) { - /* Kill no-session cgroup */ + /* Kill user cgroup */ if ((r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, user_path, true)) < 0) pam_syslog(handle, LOG_ERR, "Failed to kill user cgroup: %s", strerror(-r)); } else { @@ -464,16 +562,19 @@ _public_ PAM_EXTERN int pam_sm_close_session( r = -EBUSY; } + STRV_FOREACH(c, controllers) + cg_trim(*c, user_path, true); + if (r >= 0) { const char *runtime_dir; - /* This will migrate us to the /user cgroup. */ - if ((runtime_dir = pam_getenv(handle, "XDG_RUNTIME_DIR"))) if ((r = rm_rf(runtime_dir, false, true)) < 0) pam_syslog(handle, LOG_ERR, "Failed to remove runtime directory: %s", strerror(-r)); } + /* pam_syslog(handle, LOG_DEBUG, "pam-systemd done"); */ + r = PAM_SUCCESS; finish: @@ -484,5 +585,7 @@ finish: free(nosession_path); free(user_path); + strv_free(controllers); + return r; }